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Project Proposal and Feasibility Study
The Diesel Crew
Team One
Adam Alexander, Michael Lubben, Angus Richeson, and
Thomas Voss
ENGR 339 - Senior Design Project
Calvin College
09 Dec 2013
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© 2013, The Diesel Crew and Calvin College
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Executive Summary
Calvin College Senior Design Team One, The Diesel Crew, is designing and prototyping a reactor
system to convert waste cooking oil into biodiesel. Biodiesel has re-gained interest in the last decade as
an alternative to petrol diesel, with rising fuel prices and an ever increasing push towards sustainability.
The exploration of alternative fuel sources is a common interest of the members of The Diesel Crew,
which has led to the selection of this project.
The design criteria for the prototype are that the system must be easily portable, simple to
operate, and have a relatively quick production time while addressing all safety concerns, such as
chemical exposure, flammability and high temperatures. These criteria were chosen on the values of
stewardship, transparency and responsibility to end-user that are shared by the team members.
This report details the design of system that filters crude waste cooking oil, converts it to form
biodiesel, recovers and re-cycles un-reacted reagents, and purifies the biodiesel product. The project is
well into the research and design phase, and some design components are in the testing phase.
Continuing work will complete the design and deliver a working prototype by May, 2014.
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Table of Contents
© 2013, The Diesel Crew and Calvin College .......................................................................... ii
Executive Summary ................................................................................................................ iii
Table of Contents ..................................................................................................................... iv
Table of Figures ...................................................................................................................... vii
Table of Tables ........................................................................................................................ vii
Summary of Important Abbreviations in Document ................................................ viii
1 Introduction ........................................................................................................................ 9
1.1 Problem Statement .............................................................................................................................. 9
1.2 Objectives ................................................................................................................................................ 9
1.3 Scope ......................................................................................................................................................... 9
1.4 Background ............................................................................................................................................ 9
1.5 Potential Customers ......................................................................................................................... 11
1.6 Introduction to Rinnova Design ................................................................................................... 11
1.6.1 Issues with Rinnova Design.................................................................................................................. 11
1.6.2 Requirement and Goals .......................................................................................................................... 12
2 Budget ................................................................................................................................. 13
3 Safety ................................................................................................................................... 15
4 Environmental Considerations .................................................................................. 17
5 Plan of Action .................................................................................................................... 18
5.1 Project Management ........................................................................................................................ 18
5.2 Team Organization ........................................................................................................................... 19
5.3 Budget ................................................................................................................................................... 19
5.4 Method of Approach ......................................................................................................................... 19
6 Requirements ................................................................................................................... 20
6.1 Interface Requirements .................................................................................................................. 20
6.2 Functional Requirements .............................................................................................................. 20
6.3 Performance Requirements .......................................................................................................... 20
6.4 Environmental Requirements ...................................................................................................... 20
7 Task Specifications and Schedule .............................................................................. 22
8 System Architecture ....................................................................................................... 23
9 Integration, Test, Debug ............................................................................................... 24
9.1 General Testing Procedure ............................................................................................................ 24
9.2 HPLC Summary .................................................................................................................................. 24
9.2.1 Standard Selection ................................................................................................................................... 24
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9.2.2 Optimization of Peaks ............................................................................................................................. 25
9.2.3 Calibration Curves .................................................................................................................................... 25
10 Design .............................................................................................................................. 26
10.1 System Housing ............................................................................................................................. 26
10.1.1 Design Criteria ........................................................................................................................................... 26
10.1.2 Design Decision ......................................................................................................................................... 26
10.2 Material Storage ............................................................................................................................ 27
10.2.1 Design Criteria ........................................................................................................................................... 27
10.2.2 Design Alternatives .................................................................................................................................. 27
10.2.2.1 High-Density Polyethylene Container ....................................................................................................... 27 10.2.2.2 Stainless Steel Container ................................................................................................................................. 28 10.2.2.3 Glass Containers ................................................................................................................................................. 28
10.2.3 Design Decision ......................................................................................................................................... 28
10.3 Pre-Filtration.................................................................................................................................. 28
10.3.1 Coarse Filter ................................................................................................................................................ 28 10.3.1.1 Design Criteria ..................................................................................................................................................... 28 10.3.1.2 Design Alternatives ........................................................................................................................................... 29 10.3.1.3 Design Decision ................................................................................................................................................... 29
10.3.2 Dewatering .................................................................................................................................................. 29
10.3.2.1 Design Criteria ..................................................................................................................................................... 30 10.3.2.2 Design Alternatives ........................................................................................................................................... 30 10.3.2.3 Design Decision ................................................................................................................................................... 31
10.3.3 Fine Filter ..................................................................................................................................................... 31
10.3.3.1 Design Criteria ..................................................................................................................................................... 31 10.3.3.2 Design Alternatives ........................................................................................................................................... 31 10.3.3.3 Design Decision ................................................................................................................................................... 32
10.4 Catalyst ............................................................................................................................................. 32
10.4.1 Design Criteria ........................................................................................................................................... 32
10.4.2 Design Alternatives .................................................................................................................................. 33 10.4.2.1 Potassium Hydroxide in Methanol ............................................................................................................. 33 10.4.2.2 Solid Zirconium Oxide ...................................................................................................................................... 33 10.4.2.3 Solid Calcium Oxide ........................................................................................................................................... 33 10.4.2.4 Solid Magnesium Oxide ................................................................................................................................... 34 10.4.2.5 Solid Strontium Oxide ...................................................................................................................................... 34
10.4.3 Design Decision ......................................................................................................................................... 34
10.5 Reactor ............................................................................................................................................. 34
10.5.1 Design Criteria ........................................................................................................................................... 34
10.5.2 Design Alternatives .................................................................................................................................. 35 10.5.2.1 Simple Batch Reactor .............................................................................................................................................. 35 10.5.2.2 Simple Continuous-Stirred Tank Reactor (CSTR) ........................................................................................ 35 10.5.2.3 Simple Plug Flow Reactor (PFR) ................................................................................................................. 35 10.5.2.4 Simple Packed Bed Reactor (PBR) ............................................................................................................. 35 10.5.2.5 Supercritical Methanol Reactor ................................................................................................................... 36 10.5.2.6 Standard Tube Microreactor ......................................................................................................................... 36 10.5.2.7 Acoustical Cavitation Reactor (ACR) ......................................................................................................... 36
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10.5.2.8 Hydrodynamic Cavitation Reactor (HCR) ............................................................................................... 36 10.5.2.9 Microwave Reactor............................................................................................................................................ 37 10.5.2.10 Oscillatory Baffled Reactor (OBR) .............................................................................................................. 37 10.5.2.11 Motionless Inline Reactor (MIRs) ............................................................................................................... 37 10.5.2.12 Membrane Reactor ............................................................................................................................................ 37 10.5.2.13 Reactive Distillation Reactor (RDRs) ........................................................................................................ 37
10.5.3 Design Decision ......................................................................................................................................... 38
10.6 Catalyst Recovery ......................................................................................................................... 40
10.6.1 Design Criteria ........................................................................................................................................... 40
10.6.2 Design Alternatives .................................................................................................................................. 40 10.6.2.1 Fine Wire Mesh ................................................................................................................................................... 40 10.6.2.2 Bag Filter ................................................................................................................................................................ 40 10.6.2.3 Diesel Filter ........................................................................................................................................................... 40
10.6.3 Design Decision ......................................................................................................................................... 40
10.8 Separator ......................................................................................................................................... 42
10.8.1 Design Criteria ........................................................................................................................................... 42
10.8.2 Design Alternatives .................................................................................................................................. 42
10.8.2.1 Settling Tank ........................................................................................................................................................ 42 10.8.2.2 Centrifuge .............................................................................................................................................................. 42
10.8.3 Design Decision ......................................................................................................................................... 42
10.9 Biodiesel Purification .................................................................................................................. 43
10.9.1 Design Criteria ........................................................................................................................................... 43
10.9.2 Design Alternatives .................................................................................................................................. 43
10.9.2.1 Ion-exchange Resin Column .......................................................................................................................... 43 10.9.2.2 Water Wash .......................................................................................................................................................... 43 10.9.2.3 Magnesium Silicate ............................................................................................................................................ 43
10.9.3 Design Decision ......................................................................................................................................... 44
11 Preliminary Design ..................................................................................................... 45
12 Business Plan ................................................................................................................ 47
12.1 Marketing Study ............................................................................................................................ 47
12.1.1 Competition ................................................................................................................................................ 47
12.1.2 Market Survey ............................................................................................................................................ 47
12.1.2.1 Target market ...................................................................................................................................................... 47 12.1.2.2 Customers' motivation to buy ...................................................................................................................... 47 12.1.2.3 Market size and trends .................................................................................................................................... 48
12.2 Cost Estimate .................................................................................................................................. 48
13 Conclusion ..................................................................................................................... 49
14 Acknowledgements .................................................................................................... 50
15 References ..................................................................................................................... 51
16 Appendices ....................................................................................................................... I
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Table of Figures Figure 1-1 Conversion of Biological Oils to Biodiesel. ................................................................................. 10
Figure 1-2 Reversible reaction of FAME to FFA. ......................................................................................... 10
Figure 1-3 Soap Making Process (also known as saponification) ............................................................... 10
Figure 3-1 NFR Safety Labels ....................................................................................................................... 15
Figure 3-2 HMIS Labels ............................................................................................................................. 15
Figure 7-1 WBS Diagram Showing Dependencies ..................................................................................... 22
Figure 8-1 Process Overview of Reaction System ...................................................................................... 23
Figure 10-1 Reactor System Pre-built Frame ............................................................................................. 27
Figure 10-2 Glass condenser Available to Use for Methanol Recovery ..................................................... 41
Figure 11-1 PFD Summary of Preliminary Design .................................................................................... 46
Figure 16-1 FAME Molecular Weight Calculation for Soy Oil .................................................................. II
Figure 16-2 ASTM Specifications for B-100 ............................................................................................. III
Table of Tables Figure 1-1 Conversion of Biological Oils to Biodiesel. ................................................................................. 10
Figure 1-2 Reversible reaction of FAME to FFA. ......................................................................................... 10
Figure 1-3 Soap Making Process (also known as saponification) ............................................................... 10
Figure 3-1 NFR Safety Labels ....................................................................................................................... 15
Figure 3-2 HMIS Labels ............................................................................................................................. 15
Figure 7-1 WBS Diagram Showing Dependencies ..................................................................................... 22
Figure 8-1 Process Overview of Reaction System ...................................................................................... 23
Figure 10-1 Reactor System Pre-built Frame ............................................................................................. 27
Figure 10-2 Glass condenser Available to Use for Methanol Recovery ..................................................... 41
Figure 11-1 PFD Summary of Preliminary Design .................................................................................... 46
Figure 16-1 FAME Molecular Weight Calculation for Soy Oil .................................................................. II
Figure 16-2 ASTM Specifications for B-100 ............................................................................................. III
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Summary of Important Abbreviations in Document
American Society for Testing and Materials ........................................................................ ASTM
20 vol% Biodiesel Blend ...................................................................................................... B-20
Pure Biodiesel ....................................................................................................................... B-100
Fatty Acid Methyl Ester ........................................................................................................ FAME
Free Fatty Acid ..................................................................................................................... FFA
Continuous Stirred Reactor ................................................................................................... CSTR
High Density Polyethylene ................................................................................................... HDPE
High Pressure Liquid Chromatography ................................................................................ HPLC
Methanol ............................................................................................................................... MeOH
Material Safety Data Sheets .................................................................................................. MSDS
Occupational Safety and Health Admin................................................................................ OSHA
Packed Bed Reactor .............................................................................................................. PBR
Plug Flow Reactor ................................................................................................................ PFR
Process Flow Diagram .......................................................................................................... PFD
Ultra Violet Visible Spectroscopy ..................................................................................... UV-VIS
Work Breakdown Structure ............................................................................................... WBS
Waste Cooking Oil ................................................................................................................ WCO
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1 Introduction
1.1 Problem Statement
As the demand for energy proliferates in the world, especially as developing countries increase
their use of technology, the need for improved and more sustainable energy resources increases. A large
area of concern in sustainable energy is the transportation industry. Traditionally the energy resource
for transportation has been petroleum based, however petroleum is a non-renewable resource, and at
some point in the future, petroleum may not be accessible in quantities to support the needs of this
world. An alternative to using petroleum is the use of electricity via batteries. Many renewable sources
of energy are available to produce electricity, however efficient and economical means of harnessing
this form of energy in the transportation industry are not well developed. A possible solution is to use a
fuel that is renewable, such as biodiesel, a fuel so named because it can be harvested in a variety of
ways from plants and animal fat. A particular attractive method is the conversion of waste cooking oil
(WCO) to a usable bio diesel as this not only reduces waste but produces something that can be used.
The Diesel Crew’s aim is to develop a system to perform this conversion for an institution such as Calvin
College.
1.2 Objectives
The primary objective of this group is to improve on a previous senior design group’s design and
build a prototype continuous flow reactor to convert WCO into a usable biodiesel fuel that meets the
standards and qualities of ASTM for biodiesel fuel, which is necessary for the fuel to be sold
commercially. The design shall be easily usable for an institution such as Calvin College and operated by
a person of non-technical background.
1.3 Scope
This group has placed several limitations on this project. The objective of this project is to
improve upon the design of Team Rinnova of 2008. Team One has defined a better process as one that
is quicker, smaller, less expensive, and easily operable. A shorter operation time is more user friendly,
especially for an institution such as Calvin College that may not have the funds to pay for a full time
operator of the equipment. In addition, a smaller scale design is more manageable, creates less safety
concerns and should lower costs. For the design of this system, and in an effort to be good stewards of
the resources available, this team will use the WCO from Calvin College’s dining services.
1.4 Background
Raw cooking oils should not be used directly as fuel in most engines as the higher viscosity of
these oils results in carbon buildup and thus reduced engine life (US Department of Energy). Therefore,
further processing is needed. One such option is pyrolytic cracking, but due to the high temperatures
involved (Maher and Bressler, Scientific.net) the team chose to produce the more popular product, fatty
acid methyl esters, also known as FAME.
FAME, commonly called biodiesel, is typically used in a blend with traditional petroleum diesel.
Biodiesel is made by converting oils or fats, which are triglycerides, and an alcohol (usually methanol) to
fatty acid esters in a process known as transesterification. This process is shown below in Figure 1-1.
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Ideally, this is done in a single step with feedstock oil that consists only of triglycerides. However, in
practice waste oils also contain water and free fatty acids (FFA), carbon chains not bound to a glycerol
backbone. The presence of water and FFA is problematic as one of the preferred methods of enacting
transesterification is by using a basic (alkali) catalyst such as sodium hydroxide (NaOH), which forms
soap when added to FFA as shown in Figure 1-3 (Suwannakarn). While substantial water in the final
biodiesel product is not acceptable by itself, a large fraction of water also exacerbates the FFA to soap
problem, converting biodiesel to FFAs in the reaction shown in Figure 1-2 (Rinnova). Besides using oils
that could be converted to biodiesel, impeding process flow, and deactivating heterogeneous catalysts,
soap is also an emulsifier, making it more difficult to separate whatever water is present from the
produced biodiesel, further reducing yield.
Figure 1-1 Conversion of Biological Oils to Biodiesel.
Note: This reaction is usually done with a catalyst and a large amount of methanol to increase the rate and equilibrium
conversion towards biodiesel.
Rinnova chose to address these issues via a two-step batch reaction process, utilizing an acid
catalyzed pretreatment to esterify FFA, removing methanol via vacuum before proceeding with a base-
catalyzed transesterification using potassium hydroxide. The acid pre-treatment is simply the reaction
shown in Figure 1-2 driven in reverse (from right to left).
Figure 1-2 Reversible reaction of FAME to FFA. Note: This also illustrates another benefit of having an excess of methanol, since existing FFAs will be better driven to biodiesel.
Figure 1-3 Soap Making Process (also known as saponification)
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Rinnova then used vacuum vaporization to recover the remaining methanol before draining the
waste glycerol and using a water wash to remove any remaining FFA, glycerol, or soap that might have
been dissolved in the biodiesel (the water is then also drained from the reactor). This washing step was
followed by passing the biodiesel through an Amberlite™ polishing column to purify the final biodiesel
product. The resulting Rinnova system was designed to produce 45 gallons of biodiesel in roughly 16
hours (2.8gal/hr) at an estimated cost of $2.31/gal, if the WCO was purchased, or $1.17/gal if WCO was
free (Rinnova).
1.5 Potential Customers
Any institution that produces WCO from their dining services that also has a moderate need for
diesel fuel for transportation or lawn maintenance is a potential customer. The team will tailor the
design to meet the needs of a smaller institution such as Calvin College, which produces about 2000
pounds of WCO per month. Currently Calvin operates a shuttle van on biodiesel as well as a few
lawnmowers. In addition, an engineering class, Engineering 333, Thermal Systems Design, is working on
a project to modify more lawnmowers to run on a blend of biodiesel and petrol diesel. The reactor
would help cut costs of purchasing fuel for this machinery.
A reactor of this type would also be useful to a larger chemical recycler that takes in WCO.
Currently, many companies collect WCO and convert it to FAME in large batch processes with
homogenous catalyst. One such company, collects and converts Calvin College’s WCO. A company such
as this would benefit from a continuous process due to the lower amount of labor required for
operation and less separation time.
For an institution to implement our reactor system, the design must meet a few requirements.
First and foremost it must be completely safe to operate, not putting the operator or anyone else in
danger. Detailed safety concerns and requirements can be found later in the report in Section 3.
Secondly, as part of the scope, and a major design concern, the system must be easy to operate by a
person of nontechnical background. Furthermore, the design should not require constant personal
monitoring while running. This goal can be achieved through a continuous reactor system and simple
temperature and electronic controls. A detailed instruction booklet for operation, safety, maintenance,
and troubleshooting will be written upon completion of design.
1.6 Introduction to Rinnova Design
The Diesel Crew is working to improve upon the work completed by Team Rinnova of 2008.
Team Rinnova designed and built a prototype batch reactor system to perform the same conversion.
Working with a grant from the state of Michigan, Rinnova had a budget of $6000 and built a 55 gallon
reactor with an operation time of 16 hours. In addition Rinnova implemented a detailed controls system
with timers to help reduce required observation time by the operator.
1.6.1 Issues with Rinnova Design
The Rinnova design was good, but the team feels with further research and suggestions
provided by Rinnova, the design can be improved. First, the team would like to shorten the reaction
time. The Rinnova team used an acid catalyzed esterification reaction for the FFA conversion, and a base
catalyzed trans-esterification of the triglycerides. As mentioned previously, this two-step process
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requires a water washing after each step. The water removal requires a long settling time. The team
hopes to avoid this step by using a metal oxide heterogeneous catalyst. An operation time of sixteen
hours is too long for non-industrial use. However, the Rinnova design can produce an estimated three
gallons per hour and the team would like to at least repeat this production rate for a continuous
process.
In addition, Rinnova used bag filters that they designed; according to Phil Jaspers, these filters
did not work well, and he switched to a normal petrol-diesel filter. Lastly, Rinnova’s design required
much interaction between the operator and the system, switching valves, and monitoring pumps and
temperature controls.
1.6.2 Requirement and Goals
While maintaining safety precautions and environmental standards, The Diesel Crew hopes to
implement a design that shall meet the following requirements and goals:
Smaller scale reactor than team Rinnova. Shall be able to fit through a standard door
frame for ease of mobility
Shall have improved filtering sections
Shall have faster operation time, i.e. less than 16 hours and produce three gallons per
hour
Transparency of design in that the operation is easily performed with little instruction by
a non-professional.
The parts are easily serviceable, and those that need replacement (filters, tubing) are
easily found and inexpensive.
Meet all safety requirements
The end product meets the required quality standard for biodiesel.
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2 Budget
An estimated cost of the project is shown in Table 2-1.
Table 2-1 Itemized Cost Estimate as of 7-Dec-2013
Note: Many prices included as zero because they have been or will likely be acquired for free.
Component Price Size Quantity sub-Total Shipping Extra Costs Total
Methanol 20.00$ 4-1 gal 5 100.00$ -$ 100.00$
Waste Oil -$ Gallons -$ -$ -$
MgO Powder -$ 230 g -$ -$ -$
CaO Powder 5.00$ 15 10 50.00$ 15.00$ 65.00$
Wire Mesh 22.00$ strainer 1 22.00$ 10.00$ 32.00$
Filter Container -$ -$
Holding Tank -$ -$ -$
Feed Pump -$ -$ -$
Dewatering Heater 10.00$ 1500 w 2 20.00$ 20.00$ 40.00$
Dewatering Vessel -$ -$ -$
Temperature Sensor 25.00$ 1 25.00$ 15.00$ 40.00$
Vacuum Pump -$ 2 -$ -$ -$
Water Catcher 8.00$ 1000 mL 1 8.00$ 12.00$ 20.00$
Fine Filter Container -$ 1 -$ -$
Fine Filter Cartridge 4.00$ 5 20.00$ 6.00$ 26.00$
Reservoir 25.00$ 5 gal. 1 25.00$ 1.00$ 5.00$ 31.00$
alt:mfg container 1-55 gal. 1 -$ -$ 15.00$ 15.00$
ex-Pfizer vessel -$ 30 L 1 -$ -$ 10.00$ 10.00$
alt:steel pipe 27.00$ 10L??? 4 108.00$ 12.00$ 10.00$ 130.00$
heater 130.00$ 9kw? 1 130.00$ 15.00$ 3.00$ 148.00$
insulation, pipe 10.00$ 10ft. 2 20.00$ 20.00$
insulation, vessel 10.00$ 12ft^2 1 -$
pentek bag filter 20.00$ ~20" 2 40.00$ 5.00$ -$ 45.00$
ex-pfizer glass -$ 1 -$ -$ -$
Alt: DIY w/steel/HDPE 45.00$ 1 45.00$ -$ 45.00$
ex-pfizerCondensor -$ 1 -$ -$ -$
vacuum from Calvin -$ 1 -$ -$ -$
CH3OH tank 10.00$ 1 gal. 1 10.00$ 0.50$ 2.00$ 12.50$
pump from Calvin -$ 1 -$ 3.00$ 3.00$
alt:pump 25.00$ 1 25.00$ 3.00$ 28.00$
Cornelius Keg (for column) 23.00$ 1 23.00$ included 23.00$
quick connect fittings 8.00$ 2 16.00$ included 16.00$
4 lbs glass marbles 5.00$ 1 5.00$ included 5.00$
#80 stainless steel mesh 6.00$ 1 6.00$ included 6.00$
1 lb Amberlite BD10Dry 72.00$ 1 72.00$ included 72.00$
in-line filter housing 5.00$ 1 5.00$ included 5.00$
diesel filter 2.00$ 2 4.00$ included 4.00$
fittings 5.00$ 2 10.00$ included 10.00$
5 gallon bucket 5.00$ 2 10.00$ included 10.00$
bucket lid 1.50$ 2 3.00$ included 3.00$
5 gal diesel container 15.00$ 2 30.00$ included 30.00$
*optional 14 gal fuel caddy 120.00$ 1 120.00$ included 120.00$
10 feet 1/2" copper tubing 15.00$ 2 30.00$ included 30.00$
5 feet braided stainless steel tubing 50.00$ 1 50.00$ included 50.00$
1/2" copper fittings (elbows/ nipples/ tees) 1.20$ 30 36.00$ included 36.00$
3 way brass valves 12.00$ 4 48.00$ included 48.00$
electrical wiring 45.00$ 1 45.00$ included 45.00$
electrical circuitry (relays/ breakers…) 150.00$ 1 150.00$ included 150.00$
*optional-temperature sensors 11.00$ 6 66.00$ included 66.00$
*optional- control unit 120.00$ 1 120.00$ included 120.00$
4 gallons of methanol 20.00$ 4-1 gal 1 20.00$ included 20.00$
waste vegetable oil -$ 1 -$ included -$
glassware for testing -$ 1 -$ included -$
vacuum distilattion column -$ 1 -$ included -$
200 grams KOH 5.00$ 1 5.00$ included 5.00$
HPLC Standards 42.00$ 1 42.00$ 42.00$
Administrative Printing 0.05$ B&W pg 300 15.00$ 15.00$
Contingency 30% 505.35$
Total 1,579.00$ 111.50$ 51.00$ 2,246.85$
Course Filter
Feed Components
Costs for
Experimentation
Miscellaneous
Biodiesel Collection
Tank
Glycerol Waste
Storage
Final Diesel Filter
Polishing Column
Equiptment
Fine Filter Device
Dewatering Device
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The cost estimate in Table 2-1 does not give an accurate number for what the team plans to
spend, but rather gives the cost for the project if everything was purchased. There are even costs for
some competing alternatives included in the table. The team has submitted a budget proposal to Calvin
College and expects to receive an approved budget of somewhere from $500 to $1000 from Calvin. The
gap in budget will be met by finding less expensive alternatives, getting donated components, and
possibly finding additional sponsors for the project. The money actually spent on the project to date is
shown in Table 2-2 below.
Table 2-2 Record of Spending to Date
Item Amount Total Cost (USD) Date
PFD Printout (Consultant) 1 0.35 21-Nov-13
Methanol 5 cases of 4 gal 100 5-Dec-13
FAME Standard for HPLC 1 72 3-Dec-13
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3 Safety
The material safety data sheets (MSDSs) for the primary chemicals used have been consulted to
find the care that should be taken while working with the chemicals. None of the chemicals used in this
project should be ingested, and care should be taken to make sure that they aren’t inhaled, as all of
these chemicals have some negative health effects. However, the main concern is flammability of MeOH
and FAME (Advanced Organic Materials). The NFR safety labels are shown in Figure 3-1 (Science Lab).
MeOH Soy Bean Oil FAME Glycerol
Figure 3-1 NFR Safety Labels
Hazardous Material Safety Identification System (HMIS) labels are shown in Figure 3-2.
MeOH Soy Bean Oil FAME Glycerol
Figure 3-2 HMIS Labels
HMIS personal protection designations:
A – Glasses
G – Glasses, Gloves, Respirator
H – Glasses, Gloves, Synthetic Apron, Respirator
In addition, Calcium Oxide (CaO), the chosen reactor catalyst, is slightly reactive with water and
can cause chemical burns.
Proper protection has been and will be utilized in working with the chemicals in this project.
Especially with flammable chemicals, electricity can pose a hazard. Care will be taken to make sure
OSHA requirements are met with regard to electrical connections and wiring, so there will not be any
ignition sources for the flammable chemicals.
There will also likely be pressures over 1 atm in the system, specifically in the reactor. The
glassware, piping, and other equipment used will be specified to operate above the pressures used.
Furthermore, a thin wire mesh will be wrapped around all glassware, so if it does rupture, glass
fragments cannot fly past the cage causing further damage or harm.
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Designs also consist of using a microwave. Operating a microwave for long periods of time could
become a safety concern. To investigate this concern, a test will be done running a microwave for
several hours with water being pumped through the microwave to see if the microwave explodes, is
damaged or other adverse effects occur. The team will also make sure no materials stay in the
microwave that absorb microwaves, specifically certain metals and certain plastics that slowly degrade
when exposed to microwaves.
Waste can also pose as a safety hazard if not properly taken care of. The group has labeled
containers for WCO. MeOH has chemical labels from Sigma Aldrich. The FAME is to be put in labeled
high density polyethylene (HDPE) containers. Dr. Tatko and Rich Huisman of the Chemistry department
have been consulted about dealing with chemical waste, which will be put in HDPE containers with the
contents labeled and disposed of by the proper methods by Rich Huisman after the end of the spring
semester. The group has specific meetings in January with Heather Chapman from the Calvin College
Environmental Health and Occupational Safety department to further discuss safety for the spring.
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4 Environmental Considerations
The environmental impact of this project comes from two viewpoints, a direct and indirect
impact. The direct impact is the result of interaction of the reactor and the immediate environment
surrounding it, and extending to the locale of where reactants were obtained and where the products
are distributed. The indirect impact is the potential influence the technology of this kind can have on the
physical world.
This team considered the direct impacts more carefully when making design decisions, and will
continue to do so as the prototype is further developed in the upcoming semester. The direct impacts
on the environment are positive, however a negative impact can be made if the waste is not properly
disposed of. First, the team is designing and building a system that uses up waste, a very positive effect,
as the earth has a very limited amount of room for garbage. Secondly, glycerol is a byproduct of the
reaction that will be disposed of appropriately. In fact, many waste water treatment plants will welcome
glycerol as it makes for a good feed for the bacteria in the anaerobic digester. Lastly, methanol, a very
volatile chemical, will be used in the reaction, and unfortunately is quite harmful for people. Great care
will be taken in the design and construction of the prototype to ensure that no methanol will leak from
the system and expose people in the surrounding environment to methanol.
The technology of this kind has the potential to have a very positive impact on the environment.
As mentioned previously, waste is not only being handled with care, but also reused, furthering the role
of humans as good stewards of the resources God has blessed us with. In addition, the product of this
“waste” is valuable fuel that can replace regular petro diesel, without losing much performance of the
engine. This fact is key as the dependency on oil, a non-renewable resource needs to be reduced. Lastly,
if the biodiesel industry does take off, a very large amount of glycerol will be produced as a byproduct.
This glycerol can be implemented in many different uses, such as, anaerobic digesters, a component of
livestock feed, and purified glycerol has medicinal and personal care product benefits (Yang, Milford and
Sun). Lastly, when bio diesel is blended with petro diesel, the carbon dioxide and sulfur dioxide
emissions are reduced (Agency). This team recognizes the benefit of these impacts, and these benefits
caused the project to be attractive to this team.
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5 Plan of Action
This section of the report discusses the organization and communication of The Diesel Crew
between each other and consultants, as well as the culture of the team.
5.1 Project Management
To complete this project, a schedule of deadlines was set. This schedule was a combination of
class deadlines and project deadlines. The team chose Google calendar as the means to communicate
deadlines of tasks and assignments. Google calendar allows for pop up reminders and emails to be sent
for events and tasks that were set. A short list of deadlines can be seen below. The deadlines were set to
allow for unforeseen issues that arise with any projects.
Table 5-1 Summary of Deadlines
Task Deadline
Model Built January 15, 2013
HPLC Method December 20, 2013
Research and Design Completed January 30, 2014
Parts Ordering and Assembly March 15, 2014
Senior Design Night May 2014
Final Report May 2014
Finishing the design early allows for extra time to find, order, and wait for parts to arrive for
assembly. In addition the reactor system should be assembled early in the spring to allow for
optimization and troubleshooting of the system; often issues arise with the scale up of design.
Furthermore the system involves a continuous process, which is dependent on steady state. For testing
of the system the team will not be able to run the reactor constantly and will have much start up and
shutdown transient analysis.
The team agreed to meet twice a week as a team, Wednesday nights at 6:30 and Friday
mornings at 9:00. The team used these meetings to discuss and communicate individual progress to the
team. In addition the group discussed new tasks and assigned them to group members accordingly. Tom
kept minutes in a word document with each new date as a heading. The minutes can be found in the
folder labeled organization in the team folder on the shared drive. If deadlines were not met,
adjustments were made depending on the importance and urgency of the task, sometimes the deadline
was moved back, while other times group members were reassigned to assist in the completion of that
specific task so as not to fall behind.
In addition to meeting as a team twice a week, the team also met with Professor Sykes once a
week on Tuesday to give updates on current progress status. Professor Sykes gave insight and advice on
project ideas and feedback on current project progress. Furthermore, Professor Sykes put the team in
contact with Bob Aupperlee as an industrial consultant. Bob has worked for Exxon Mobile in their
research division. Bob gave the team new insights and concerns with catalyst recovery, reactor design
considerations, and suggestions for staying on task to complete the project on time.
Lastly, the team requested the help and expertise of Professor Chad Tatko, a chemistry
Professor, on HPLC analysis. Professor Tatko was a vital resource this past semester as he obtained a
19
HPLC unit with an auto sampler for the team’s personal use. He also gave advice on the methodology
development, and also method of experimentation with the catalyst that will be implemented after the
break.
5.2 Team Organization
As well meeting assigned deadlines and completing tasks for the project, the team had to carry
out assignments for the senior design class. This was done by organizing the team in the following way.
Adam was assigned to be the team webmaster. He developed and constructed the website and
will continue to update the site with current project details and accomplishments on a biweekly
basis. Adam also assisted Angus with design research.
Mike took on the task of poster design and submission of assignments. Periodically throughout
the semester Mike updated the project poster by the team station as the team advanced along
in the work. Secondly, Mike was in charge of ensuring that every assignment was completed and
submitted by the due date.
Tom became the team organizer, as he is the only member of the group with an inclination
towards judging from the Myer-Briggs test. Tom was in charge of the Google calendar and taking
minutes for each of the team meetings. He helped keep the group on schedule, reminding
members of deadlines.
Angus was given the task of researcher and experimenter. Although Angus cannot complete
these tasks by himself, these areas were his main focus.
5.3 Budget
Mike is in charge of managing the budget; submitting purchases, marking them down, etc. Mike
will be sure to complete order forms promptly and succinctly. A record of the current spending and
budget total will be kept as an Excel file. Mike will notify other team members as soon as he believes
that the team may go over budget. Arrangements can then be made to address these issues.
5.4 Method of Approach
Cooperation is essential in any team project and is one aspect the team excelled at this past
semester. The success of the team depended on the quality and timeliness of the individual work,
whether it was researching new methods, or making new contacts. Team meetings went smoothly,
ideas were encouraged, and the discussion floor was shared evenly amongst members, i.e. no one
person was allowed to dominate the meeting. Each member attempted to hold themselves and others
accountable while remembering that each teammate had outside responsibilities in addition to those of
the team.
Major design decisions were made as a group, often using a design matrix to show important
details. Each team member voiced their concerns and a decision was made final only upon full
agreement. Before design decisions were made, individuals conducted their own research and brought
forth the information to other teammates so that a well-informed discussion could be had, and a good
decision was made.
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6 Requirements
6.1 Interface Requirements
The operation of the prototype will be explained in a user manual. The user manual will explain
everything from preparation of the feedstock to cleaning, shut down, ordering materials, and fixing
potential issues. The combination of the prototype and manual should result in a system that is easily
operable without an engineering background. The ease of user interaction is of high value to the design;
the ability to operate the reactor without extensive technical knowledge will allow the system to be
used at an institution such as Calvin College. The goal is to design the system to be independent of
human operator except for startup and shutdown. This shall be accomplished through a control system
that will regulate system conditions, such as temperature, pressure and flow rate.
6.2 Functional Requirements
The functional requirements for the prototype is that it produces FAME using MeOH and WCO
as feedstock. The prototype needs to be able to hold all of the feedstock, products, and waste products.
Any necessary measurements by a user should be done with the prototype, not additional tooling.
Lastly, the prototype should have ease of mobility, i.e. should fit through a standard door frame.
6.3 Performance Requirements
The prototype product needs to meet the ASTM standards for biodiesel (National Biodiesel
Board, 2007). A glyceride content specification was determined from the European Standard (European
Committee for Standardization, 2004). To achieve a product below the maximum glyceride content
without a separation of unreacted glycerides from FAME, a 96.5% conversion must be achieved. Key
requirements are detailed in Table 6-1 Selected Biodiesel Product Specifications below.
Table 6-1 Selected Biodiesel Product Specifications
Property Limit Units
Glycerol (Total) 0.24 max % Mass
Free Glycerol 0.02 max % Mass
MeOH 0.2 max % Volume
Magnesium and Calcium (combined) 5 max PPM
Sodium and Potassium (combined) 5 max PPM
Water and Sediment 0.05 max % Volume
Monoglycerides 0.8 max % Mass
Diglycerides 0.2 max % Mass
Triglycerides 0.2 max % Mass
* Full ASTM specifications for biodiesel can be viewed in Appendix D.
6.4 Environmental Requirements
Feedstock will be so low in sulfur content, so SO2 will not be a concern as an emission from the
combusted product. The glycerol bi-product is environmentally safe, and is typically discarded with
wastewater. However, if there is a significant amount of FAME in the glycerol product, the glycerol
21
product will have to be treated as chemical waste. The team recommends users give glycerol to a
recycling facility or consult their local waste-water treatment plant. The other environmental
requirements are more specific to the area where the prototype will be operated. The storage tanks,
and most of the system will be sealed to prevent fumes, especially for MeOH which is very volatile and
fairly hazardous to human health.
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7 Task Specifications and Schedule
The break-down of tasks for the project was done in a Gannt chart on October 4th; however, the
team found that the interface for Microsoft Project was not convenient enough to update the Gannt
chart as tasks changed. The amount of time spent updating the chart was more than the helpfulness the
updated chart offered to the group. So, a Microsoft Excel spreadsheet has been used by the group
instead of a Gannt chart to keep track of tasks and their completion. The work break-down structure
(WBS) spreadsheet can be opened from the object below if accessing this document electronically, or
found in the Team01 folder (S->Teams->Team01->Organization->WBS.xlsx).
WBS.xlsx
The project is broken down into several sub-sections as shown below in Figure 7-1.
Figure 7-1 WBS Diagram Showing Dependencies
The approximate number of total hours spent by the group thus far on the project is 480 hours.
This number is very high, given a maximum number of hours of time for a class at Calvin is considered to
be three additional hours for every credited hour (four hours a week/credit). This amount of work is
considered a maximum to avoid students consistently having work weeks over seventy hours (based on
17 credits), which begins to get in the way of student’s commitments at part-time jobs, church and
other extra-curricular activities. Given that ENGR 339 is a two credit class with about 2.6 hours of lecture
a week, a fourteen week semester results in seventy-five hours of time allotted for each student to work
on material outside of class. Seventy-five hours a person equates to three hundred hours for the team,
less if time spent on individual class assignments is subtracted. Of the team’s 480 hours spent on this
project, about two hundred were spent on documentation and presentations for the class which didn’t
necessarily further progress towards a final design for the prototype. In planning, the team has taken
the lack of human resources available in the fall semester into consideration and tried to not let the
amount of overtime worked on the project get extremely high. The team has planned a significant
amount of lab work over Christmas break and Interim to avoid having to work as much overtime on the
project in the spring as was worked in the fall. The estimated remaining time needed on the project is
400 hours plus the time required to meet deadlines for the course ENGR 340.
Problem Definition
Reactor Research Filter Research Separation Research
Administrative
Filter Design
Test/Optimize
Reactor Design
Test/Optimize
Separation Design
Test/Optimize
Less Dependent Tasks
Analytical
Build & Test
Budget
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8 System Architecture
The following diagram outlines a brief overview of the process. Subsequent sections will
describe the process in further detail in section 10.
Figure 8-1 Process Overview of Reaction System
The process will filter the WCO before it enters the reactor. This filtering process will
involve initial heating, and dewatering. The effluent of the reactor will pass to the Methanol
Recovery system and the separator. The separator will allow the heavy glycerol to settle out of
the bio diesel product to then be collected as waste. The biodiesel product will then go through
a final filter to remove any particulates from the reactor such as particle fallout or remaining
catalyst.
Not shown on the diagram is the user interface and controls. A potentially extensive interface
system will control the temperatures, flow rates, and pressure of the system. As the design shall
allow for minimal user interaction, sensors, alarms and emergency shut offs will be included to
protect those in the environment near the reactor.
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9 Integration, Test, Debug
Several different parts of the final design will have to be tested and optimized. Testing will be
done in the design of the components of the system, but this section deals more specifically with the
testing of the system after the system is assembled.
9.1 General Testing Procedure
In general, once the subsystems have been individually tested using materials from lab testing,
they will be assembled into the reactor system. The idea for the final design is that the user can fill up
feedstock ‘silos’ and flip a switch to run the system. The team will probably have variable voltages on all
the electrical components, so once the switch is flipped for the first time, the oil quality will be
measured using the HPLC testing methods outlined in the HPLC section. Flow rates will be measured at
steady state by putting streams into volumetric flasks and recording the amount of time taken to reach a
given volume. In this way, the yield of the separations and throughput of the system can be measured.
One of the most important parts of testing is monitoring the temperature at certain places: the
temperature in the de-watering unit, the temperature at reactor inlet and outlet, and the temperature
of the MeOH and glycerol separation units are especially important. The power supply to these heating
elements will be adjusted to obtain the desired steady state and kept at the correct rate, so adjusting of
power input isn’t needed for later operations.
The testing of the system can be dangerous if flow is inhibited, resulting in pressure build up at
parts of the system. Noting that this is an area of concern, the team will take specific care to avoid and
monitor for this issue.
9.2 HPLC Summary
To determine how well the reactor system was working, the team needed an analytical method
to determine the conversion reached. The chosen technique was HPLC with UV-Vis. (SITE Pomona?)
HPLC is a separation technique that when partnered with UV-Vis can identify components of a mixture
and determine quantitatively the amount present through the use of standards and calibration curves.
The methodology of this technique is currently being developed and is anticipated to be finished before
Christmas Break.
9.2.1 Standard Selection
Due to the variety of compounds present with WCO, the selection of standards was chosen to
represent the entire range of possibilities. Present in the oil are triglycerides, diglycerides,
monoglycerides, free fatty acids, and the biodiesel product, FAME. However only those compounds that
have some degree of unsaturation are detectable by UV-Vis. To best represent the system, the team
chose to use monoolein (a compound from the monoglycerides), a few FFAs, and a variety of FAMEs.
Communicating with Rich Huisman and Professor Tatko, the team acquired all of the compounds
necessary for standards except for the FAME, which are summarized in Table 9-1. The FAME compounds
as a blend were obtained from Sigma Aldrich via Rich Huisman.
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Table 9-1 Summary of Standard Components for HPLC Methodology
Compound Type
Monoolein Monoglyceride
Oleic Acid Unsaturated FFA
Linoleic Acid Poly-unsaturated FFA
Lauric Acid Saturated FFA
Palmitic Acid Saturated FFA
Margaric Acid Saturated FFA
Methyl Linoleate FAME
Methyl Oleate FAME
Methyl Linolenate FAME
9.2.2 Optimization of Peaks
To accurately determine components, the separation of peaks must be optimized by changing
the conditions of the HPLC instrument, flow rate, column temperature, and solvent gradient. The
conditions are optimized by using the standards as samples. Once the conditions are determined,
unknown compounds can be identified by comparing retention times to the known retention times of
the standards. The initial method was based on a Pomona Scholarship senior thesis from Claremont
College, in which the student used a mobile phase consisting of Solvent A: 85% Acetonitrile, 15% Type I
water (0.1% TFA), Solvent B Acetone (0.1%T TFA), a flow rate of 0.7 mL/min, injections of 5 μL, a column
temperature of 50 ℃, and a wavelength of 270 nm. The Pomona group used the gradient mobile phase
shown in Table 9-2.
Table 9-2 Summary of Pomona Group Gradient Elution
Time (min) %Solvent A %Solvent B
0 100 100
10 100 100
20 70 30
40 20 80
50 0 100
60 0 100
9.2.3 Calibration Curves
Calibration curves are used to determine the amount of analyte present in the sample.
According to Beer’s law, the absorbance of the analyte is proportional to the concentration of the
analyte in solution. Calibration curves are constructed by making a range of standards in varying
concentrations, and integrating their respective peaks. A plot of the integration area vs. concentration
should be linear according to Beer’s law, and through this linear fit, the concentration of an unknown
will be determined by the absorbance level detected. To help determine how much of the triglyceride
feed is converted to FAME, the team will create a calibration curve of the monoglyceride, each of the
FAMEs, and linoleic acid. Using this method the team can identify how well the reactor conditions are
working and can optimize from there.
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10 Design
“Fifteen hours in the lab will save you one hour in the library” –Wayne Wentzheimer
Taking Dr. Wentzheimer’s advice into consideration, a great emphasis was put into initial
research of the components of our prototype reactor.
Some key properties for design are shown below in Table 10-1.
Table 10-1 Key Component Properties (at room temperature)
Component Density
(g/mL)
Density
(lb/gal)
Molecular Weight
(g/mol)
Stoichiometric
Volume (gal)
Soy Oil 0.926 7.71 872.6 1
MeOH 0.792 6.59 32.04 0.129
FAME 0.88 7.33 292.2 1.060
Glycerol 1.261 10.50 92.09 0.0775
Note: Soy Oil and FAME MW calculated from relative abundance of fatty acids (See Figure 16-1 on page II).
10.1 System Housing
The components of the system will need to be attached to a supporting structure to hold them
in place.
10.1.1 Design Criteria
Housing alternatives were evaluated for several criteria. First, the housing needs be able to hold
all of the components, save for possibly some of the material storage containers which could be on the
ground. Second, the housing needs to be able to fit through a standard door in order to meet the team’s
design requirements. Third, the team would like the prototype to be easy for a customer to transport, so
alternatives with wheels were preferred.
10.1.2 Design Decision
Shortly after the project began, the team found a steel frame (Figure 10-1) with batch reactor
equipment installed that had been donated to the Calvin College Engineering department by Pfizer, Inc.
The frame is just the right size to fit through standard doors while still being able to hold large system
components, making it an ideal solution. This frame also has castors which meets the transportation
ease criteria. Other alternatives were all more expensive than using the donated frame, so the frame
from Pfizer was the clear choice. The batch components were disassembled and stored in case they are
needed later.
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Figure 10-1 Reactor System Pre-built Frame
10.2 Material Storage
The reactor system will require a few materials to be stored nearby such as methanol, WCO,
waste glycerol, and purified biodiesel.
10.2.1 Design Criteria
The material storage must meet a few requirements for the purpose of the design. First the
storage containers must contain sufficient room for hold up, essentially the reactor system run time
should not be limited by the available reactants, (WCO and Methanol), nor by the storage of products
(biodiesel and glycerol). Secondly, the containers must be safe to use for each of the individual
components, methanol for example is highly volatile and harmful to people and must be sealed
appropriately. Third, the containment vessels should be inexpensive, and easily replaced by the end user
if necessary. Lastly, the containers should be easily accessible by the user, not requiring heavy lifting or
difficult placement within the system structure.
10.2.2 Design Alternatives
After investigating various possibilities, the team decided upon three alternatives to consider for
the design, High Density Polyethylene, stainless steel, and glass.
10.2.2.1 High-Density Polyethylene Container
High-Density Polyethylene, or HDPE, is a tough plastic that is used to store various chemicals and
comes in a large variety of volumes. This material is readily available in a form that meets the
requirements of the design. These type of containers are inexpensive and available to the general
28
public; if needed, multiple containers can be used to ensure the proper volume capacity is reached. In
addition, this material is able to handle all of the required compounds for an extended period of time.
10.2.2.2 Stainless Steel Container
Stainless steel is known to be very resistant to corrosion which is a great advantage as a material.
In addition, stainless steel can be constructed in a large variety of sizes and shapes. However, a
disadvantage of this material is its weight. The weight of the liquid stored will already be significant, and
adding the weight of the storage vessel to the system could hinder the mobility of the overall system.
Lastly, stainless steel is not easily accessible and is expensive. For this reason adding storage capacity
may be difficult.
10.2.2.3 Glass Containers
Glass containers are great for their corrosion resistance, and a glass container should be able to
handle any of the required materials for this project. Additionally, glass allows an end user to be able to
more easily monitor the levels of each chemical. However, glass containers are not abundant in large
volumes, so glass containers of required volume size, 1 to 10 gallons, are expensive. Additionally, glass is
heavy and fragile. The fragility of the glass causes a safety concern for those who may be working in the
surrounding environment.
10.2.3 Design Decision
After careful evaluation of the alternatives the team decided to use HDPE. The cost of this
material and its ease of access to both the team and end user is a great advantage. In addition, HDPE
containers are available in sizes from 5 to 55 gallons, providing a large range of storage capacity for our
materials. Lastly, for the purpose of this prototype, The Diesel Crew has access to large drums to store
waste that will result from optimizing the reactor.
10.3 Pre-Filtration
Filtering is a vital process for the design for two main reasons. First, because WCO is used as the
feedstock, the probability that the feed will have food pieces and particulates is extremely high. These
need to be removed before the oil can be fed to the system to avoid ruining pumps and possibly disturb
the kinetics of the reaction. Additionally, the water that may be present in the WCO must be removed as
water can potentially hinder the effectiveness of the catalyst (A. Refaat). The team has considered a few
different alternatives for filter design.
10.3.1 Coarse Filter
10.3.1.1 Design Criteria
The coarse filter must remove all large food pieces from the WCO that results from the frying of
food. The filter should be quick and easy to use. In addition, the filter should be easily replaced by the
end user in case the filter becomes ineffective. Lastly, the filter should be able to handle large flow rates
so that it will not easily clog.
29
10.3.1.2 Design Alternatives
The team considered two styles of coarse filters, inline, and pre-system filtration. In addition, four
types of filters were investigated, wire mesh and coffee filter which are both inline, and wire and plastic
strainers, which are both pre-system filters.
10.3.1.2.1 Wire mesh
Wire mesh has many great advantages. It is available in a large range of mesh sizes, from 1 to
325. Mesh size is a measure of the number of openings in one inch, typically measured in one dimension
(McNichols Industrial & Architectural Whole Product Solutions). Wire mesh can be implemented as an
inline filter. However, wire mesh can be expensive to obtain, especially as the design requires so little of
it, and wire mesh suppliers typically sell large quantities.
10.3.1.2.2 Coffee Filters
Coffee filters are a very inexpensive choice of filter. Additionally the coffee filter can be used as
an inline filter (as that was the original intent of the coffee filter), and the ease of access on the market
for an end user is unmatched. Additionally this type of filter will entrain fine particles, which will allow
longer use of the fine filter (later in the system). However a major drawback for coffee filters is they can
only handle a low flow rate. Due to small pore size, and high viscosity of oil, the WCO becomes trapped
and results in a very low flow rate. Experimental work concerning the temperature dependence of WCO
flow rate through a fine filter can be seen in Appendix C.
10.3.1.2.3 Wire Strainer
A wire strainer would work in a similar manner as the wire mesh filter, however the strainer
would be used as a pre-system filter. A pre-system filter allows for a much higher flow rate as the flow
through this filter is not limited by the reactor system. This is an advantage for the end user as typically
WCO is available in large volumes at a time. A pre-system filter would require a large volume to be
filtered and stored for use as needed by the reactor system. Lastly, a metal wire strainer is very durable
and has a long useful life.
10.3.1.2.4 Plastic Strainer
A plastic strainer would also be used as a pre-system filter, in a similar fashion as the wire mesh
filter. A plastic strainer offers the same advantages as a metal pre-system filter, inexpensive and large
flow rates, however a plastic filter is not as durable.
10.3.1.3 Design Decision
After careful consideration, The Diesel Crew decided to use pre-system, coarse filtration by using a
wire mesh strainer. The advantages of using a pre-system filter are clear for the end user, it has a high
flow rate capacity necessary for the large quantities of oil available at a single time, and is easily
replaced and cleaned as this filter is not integrated into the piping of the system.
10.3.2 Dewatering
Dewatering the WCO is an essential step in the process because excess water can hinder the
catalyst, by adsorbing to the catalyst sites.
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10.3.2.1 Design Criteria
The dewatering system must reduce the amount of water in the oil to 2.8 wt% (A. Refaat). In
addition to this requirement, the dewatering system should be able to remove water at a rate
compatible with the required flow rate of the reactor. Secondly, the water storage must have sufficient
capacity so as not to hinder the reactor system or else have access to a drain. Lastly, the dewatering unit
should be small and inexpensive, if possible, to help maintain the scope of the project.
10.3.2.2 Design Alternatives
The team has generated three alternatives to consider, a heater, a vacuum evaporation system,
and a combination heater-vacuum evaporation.
10.3.2.2.1 Immersion Heater
The heater system works by heating the WCO solution past the boiling temperature of water.
This can be done because of the very high boiling point of oil; in addition, the oil will not form a uniform
phase with the water readily if the water content is high, which will further help the boiling off of the
water. The heating element would consist of an electric heating coil. These heating coils are available in
many different lengths and wattages, from 750 to 5000 watt ratings. In addition the heating coils are
inexpensive.
10.3.2.2.2 Vacuum Evaporation
Vacuum evaporation works by lowering the pressure of the system and thereby lowering the
boiling point of water. A lower boiling point allows the water to be boiled faster and less expensively.
However, a vacuum system has a major disadvantage in the complexity it adds to the design. The
vacuum system will require excellent seals, a vacuum pump that can be quite large, and also a liquid
entrainment vessel. In addition, to evaporate the water near room temperature (to avoid a heating
element) the pressure must be near 0.05 bar, which is out of reach with the team’s resources.
10.3.2.2.3 Heating and Vacuum
To reduce the both the vacuum needed and the heating load, the team proposed a combination
of a heating element and vacuum filtration. However, the required pressure reduction to impact the
drop in boiling point of water requires a much larger vacuum pump than the additional heat required to
instead boil water at 100 ℃. A summary of the bubble points of water are shown in Table 10-2.
Table 10-2 Bubble Points of Water
Temperature ( ℃ ) Pressure (bar)
100 1.013
95 0.845
90 0.701
85 0.578
80 0.474
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10.3.2.3 Design Decision
After careful consideration of the options, the team decided that using just the heating element is
the best option to meet the required design requirements and scope of the project. The heating
elements that are available are inexpensive and have a broad range of power. In addition, as the
vacuum pump does not benefit the system significantly, the team opted to avoid the complexity of this
system in light of keeping the overall system simple for the end user.
10.3.3 Fine Filter
The fine filter is the final step for the WCO before it enters the reactor. The purpose of this filter is
to remove any final particulates that remain in solution that can hinder the reaction kinetics or reduce
the quality of the final product.
10.3.3.1 Design Criteria
The filter must be able to sustain a flow rate that is required by the reactor. In addition the filter
material must be easily replaceable, i.e. accessible to the user within system as well as inexpensive to
replace. Lastly, if possible an indicator will be implemented to signal when the filter is no longer usable.
10.3.3.2 Design Alternatives
The team generated four alternatives for this portion of the design, a coffee filter, centrifugal
separation, a cartridge filter and a petro diesel filter.
10.3.3.2.1 Coffee type filter
The first design is a coffee filter or a similar filter. This type of filter is easily replaceable and
accessible for all. However as mentioned previously, due to the high viscosity of oil and the fine pore
size of the filter paper the oil becomes entrained rather quickly, and results in a very low flow rate,
which is unacceptable for the design. However, as the temperature of the oil increases, the viscosity of
the oil decreases, thereby increasing the flow rate through the filter. The temperature dependence of
the viscosity of the oil is significant (see experiment in Appendix C) in this step because it takes place
after the dewatering step, which will have heated the oil significantly and hopefully increased the flow
rate through the fine filter.
10.3.3.2.2 Centrifugal Separation
The second alternative is a centrifuge. A centrifuge will easily separate the heavy particles out of
the more valuable oil. In addition, unwanted parts of the oil may be separated out based on densities.
However, this method cannot be incorporated directly into a continuous process. This filter requires all
of the feed stock oil to be pre-filtered by the operator and then stored for the system. This method is
against the requirements of this design regarding simplicity of use for the end-user.
10.3.3.2.3 Cartridge Filter
A cartridge filter works in a similar manner as the coffee filter; however, the advantage to this
design is the housing canister is already designed and built. The team actually was able to obtain a filter
housing, and cartridges from the storage room in the Engineering Building. The water filters made by
Ametek™ are of low cost.
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10.3.3.2.4 Petro Diesel Filter
The last alternative is to use a standard petro-diesel engine filter. Phil Jaspers recommended this
type of filter to the team as he used it to modify Rinnova’s design. A petro diesel filter can easily be
removed and replaced. Furthermore, this type of filter can be used in a continuous process.
10.3.3.3 Design Decision
After much consideration of the alternatives, the team chose to use the cartridge filter from
Ametek™ due to the ease of design and availability. The team will investigate the filter cartridges
currently in possession to identify the maximum flow rate through the cartridge. Ametek™ has a variety
of pore sizes available to choose from, should the need for a different pore size arise.
10.4 Catalyst
The reaction to produce biodiesel from WCO and methanol is both endothermic and reversible.
A catalyst is necessary to promote the forward reaction towards biodiesel and to reduce the reaction
time and energy input required to reach sufficient conversion. A catalyst is also required in most cases
because methanol and WCO do not mix at standard reaction temperatures and pressures. Therefore,
the catalyst acts as an intermediate to promote mixing. Many different catalysts can be used in this
process, each with its own advantages and disadvantages.
10.4.1 Design Criteria
The Diesel Crew took into consideration many criteria when choosing a reactor catalyst. The first
consideration was whether the catalyst forms a homogenous or heterogeneous mixture with the
reaction mixture. Team Rinnova used potassium hydroxide (KOH) dissolved in methanol as the catalyst
for their reaction, which worked well but required a washing step to remove the KOH. Also, the catalyst
was not able to be recycled resulting in high waste production and operating costs. To reduce total
production time, a heterogeneous (solid) catalyst is hugely beneficial because the washing step is
avoided and the catalyst can be reclaimed for use in later reactions, minimizing costs and promoting
good stewardship.
Another important characteristic of each catalyst type is its typical conversion of WCO to FAME.
Each type of catalyst has differing amount of basic sites per unit of mass for the transesterification of
triglycerides with methanol. The number of active sites can be increased by minimizing the individual
crystal size of the catalyst and by thermally pre-treating the catalyst at temperature ranging from 500-
900°C to clear off basic sites occupied by contaminants (A. A. Refaat).
Catalyst tolerance to FFAs, water, and other contaminants was also taken into consideration.
Liquid catalysts have a greater tendency to form soaps when FFAs and water are present in the reactor
mixture. The soap formed is then a great nuisance, as it clogs system components and complicates
further separation of the reactor products. Solid metal catalysts are less susceptible to soap production,
but they can be easily poisoned or inactivated by water and FFA contaminants.
Cost was an important criteria when deciding on the most appropriate catalyst. Research
performed by the team led to the discovery of many exotic catalysts that could be used to achieve high
FAME conversion, but the costs of these exotic catalysts far exceeded the budget. Cost considerations
alone severely limited the number of possible catalysts for the prototype reactor.
33
The final consideration made when choosing a reactor catalyst was the solubility of the catalyst
in the biodiesel product. Many solid metal catalysts under consideration have moderate solubility in
biodiesel requiring additional purification processes that add significant costs. Due to these factors, the
amount of leaching into biodiesel was factored into our choice of catalyst (Science Lab, Inc).
10.4.2 Design Alternatives
10.4.2.1 Potassium Hydroxide in Methanol
The most commonly used catalyst for the conversion of WCO to biodiesel is a concentrated
solution of KOH dissolved in methanol. As mentioned previously, this was the catalyst used by
Rinnova. The use of KOH as a catalyst for biodiesel production is convenient because of its ease of
accessibility, high conversion to FAME, and low cost. The downside to using KOH is that it is a
homogeneous liquid catalyst, meaning that it forms a single phase with the reactants and products.
For this reason, it is unable to be reclaimed and must be removed by a water washing process. The
washing process is very time consuming because the products must be mixed thoroughly then allowed
to settle for at least an hour (Biodiesel Basics). This process must be repeated two or three times to
achieve the required purification of biodiesel. Another disadvantage is that the KOH will form soap
with any FFA in the WCO. This disadvantage means that a rigorous pretreatment must be used to
remove all traces of FFA. KOH is classified as a very hazardous chemical, which means that additional
health and safety precautions must be put in place for its use in the reaction process (Science Lab,
Inc).
10.4.2.2 Solid Zirconium Oxide
Solid zirconium oxide (ZrO2) metal catalyst has recently been discovered as a useful catalyst in
biodiesel production. Not only does ZrO2 function as an excellent heterogeneous catalyst for the
transesterification reaction of triglycerides to FAME, it simultaneously functions as a catalyst for the
esterification reaction of FFAs to FAME. This property gives ZrO2 a unique advantage over all other
catalysts. ZrO2 achieves high FAME conversion, 90+% at the planned ambient conditions. Furthermore,
the effectiveness of ZrO2 can be improved by modification with specific anions. Sulfated and tungstated
zirconium oxides have been found to be most active for FAME conversion. ZrO2 is moderately resistant
to poisoning by water in the WCO feed and can be heat treated to restore original catalytic activity. ZrO2
and its modified derivatives have negligible solubility in the reaction mixture which adds to their
favorability as a catalyst for biodiesel production (A. Refaat). There are two primary disadvantage to
ZrO2, high cost and small particle size. The current market price for ZrO2 is $1.00/gm or more. Also, the
required particle size for ZrO2 to work as an effective catalyst is quite small making it difficult to reclaim
from the reactor effluent.
10.4.2.3 Solid Calcium Oxide
Calcium oxide (CaO, lime) in a powdered form is another viable option for reactor catalyst. CaO is
easily obtainable at low cost. As CaO mixes with the methanol, a small amount of calcium methoxide,
Ca(OCH3)2, forms which acts as an initiating reagent for transesterification. CaO also reacts with glycerol
in small amounts to form a calcium-glycerol complex that may function as the main catalyst. The
calcium-glycerol complex is soluble in FAME resulting in leaching of the CaO, a drawback to its
34
usefulness as a catalyst. Fortunately, this complex can be removed by the anion-exchange resin that the
team will be implementing into the design. The conversion percentages of WCO to FAME at the chosen
reaction conditions of 60°C and atmospheric pressure can be as high as 97% depending on catalyst
pretreatment. Pretreatment involves the thermal treatment (calcination) of the CaO at temperatures
ranging from 500-900°C to remove H2O and CO2 from basic sites on the catalyst. Calcination is improved
when the catalyst is kept in an inert environment (under nitrogen or helium) to avoid exposure to H2O
and CO2. The possibility that a pretreatment of CaO is required to achieve sufficient conversion and the
necessity of storing the catalyst in a water free environment are both negatives to this catalyst choice.
Another consideration to be made with CaO is its resistance to poisoning by water and FFA. Research
found that CaO catalytic activity can be promoted by a small presence of water, up to 2.8 wt% of the
total WCO. Higher percentages of water result in deactivation of basic sites, severely limiting FAME
conversion, as well as hydrolysis of the FAME product into FFA. CaO effectiveness for FAME conversion
decreases with the concentration of FFAs present. At elevated levels of FFAs, soap production also
becomes a major concern (A. Refaat).
10.4.2.4 Solid Magnesium Oxide
Investigation into magnesium oxide (MgO) as an inexpensive catalyst for the transesterification of
WCO to biodiesel led to the discovery that MgO has relatively high solubility in the FAME product. It was
also discovered that MgO has poor catalytic activity for the reaction of interest at the temperature and
pressure we wish to react at (A. Refaat). These two major drawbacks were enough for the team to
decide that MgO is not a suitable catalyst, and no further research was done on this catalyst.
10.4.2.5 Solid Strontium Oxide
Strontium oxide (SrO) was studied as a potential heterogeneous catalyst for biodiesel production
due to its strongly basic nature. It was found that SrO is far more active than its CaO neighbor due to
higher basicity, but it is moderately soluble in methanol (A. Refaat). No further consideration of SrO was
made due to its solubility in methanol.
10.4.3 Design Decision
Based on the extensive catalyst research performed, the Diesel Crew has chosen to proceed
with calcium oxide as the catalyst of choice for our prototype reactor. This decision was heavily
influenced by its low cost, moderate to high conversion rates, and resistance to poisoning.
10.5 Reactor
The reactor is the heart of the biodiesel generator. The chosen reactor design has a major
impact on the overall cost of the system; therefore a large focus was placed on this topic.
10.5.1 Design Criteria
The chosen reactor must be able to achieve high FAME conversion, 94-100%, at the required
reactor flow rates. The reactor must be able to achieve these conversion rates at a temperature below
the boiling point of methanol (65°C) and atmospheric pressure to avoid the need for a pressure vessel.
The reactor must also be able to accommodate a solid metal catalyst to be compatible with our
35
previously chosen CaO catalyst, or not require a catalyst at all. Additionally, the reactor must be low in
cost for construction or purchase, low in operating costs, and safe for use.
10.5.2 Design Alternatives
10.5.2.1 Simple Batch Reactor
In a simple batch reactor setup, the WCO, methanol, and chosen catalyst are added to a stirred
vessel and reacted to completion. Heat is added to the reaction either by a submerged coil heater or by
a temperature controlled jacket outside of the reactor vessel. After reaction completion, the reactor
vessel contains a mixture of FAME, unreacted glycerides, glycerol, and the remaining catalyst. The
glycerol is removed by allowing it to settle out due to its density, and the remaining reactor effluent is
processed in downstream separations. Batch reactors tend to be inexpensive and easily maintained, but
they have slow reaction times, limited FAME conversion, and a bulky size. Another negative is the
amount of user interaction required to load and unload the reactor each time it is used.
10.5.2.2 Simple Continuous-Stirred Tank Reactor (CSTR)
A CSTR is similar in design to a batch reactor in that it is a continuously stirred and heated
reactor vessel. A CSTR differs by operating in a continuous process, eliminating the need for user input.
WCO and methanol are continuously fed into the CSTR and the reactor product is removed at the same
rate. The chosen CaO heterogeneous catalyst can be kept in the reactor by the use of a fine filter at the
reactor outlet. This assumes that particle size of the catalyst is large enough to be trapped by a filter. If
the catalyst is too fine to be trapped by a simple filter, further catalyst separation operations will be put
in place as outlined in the following section. CSTRs are simple in design and operation and allow for
faster reaction times as compared to a batch reactor. They share the same negatives as a batch reactor
in that they tend to be large in size and do not achieve the highest conversion under the chosen
conditions.
10.5.2.3 Simple Plug Flow Reactor (PFR)
A PFR is essentially a hollow tube or pipe in which the reactor products, WCO, methanol, and
catalyst, are pumped through and reacted. The PFR may contain baffling to encourage mixing. PFRs have
an advantage over other reactor designs in that they provide excellent mixing of reactants without the
use of a mechanical mixing device making them somewhat simpler in design. When used with a solid
catalyst, such as CaO, special considerations must be made for the tubing material as significant
abrasion can occur at high flow rates. A limitation to PFRs is the amount of heat able to be supplied to
the reactor stream as it passes through the PFR. This can be a serious problem when dealing with the
endothermic reaction of converting WCO to biodiesel. Another serious drawback to using a PFR at the
chosen reactor conditions is the length required to achieve adequate conversion.
10.5.2.4 Simple Packed Bed Reactor (PBR)
PBRs are useful when a solid catalyst is to be used in the reaction process. A PBR consists of a
tube packed full with a solid catalyst. The catalyst is held in place by the use of a wire mesh or a reactor
bed of inert glass spheres. The reactants are then piped through the void space between the particles of
catalyst. PBRs allow for significant contact between the reactants and catalyst and are relatively simple
36
in design. The turbulence caused by the catalyst also promotes stirring of the separate liquid phases. A
negative component to the use of a PBR is that replacement of reactor catalyst is difficult as it becomes
poisoned or dissolved into the reaction mixture as is the case with the chosen reactor catalyst of CaO.
10.5.2.5 Supercritical Methanol Reactor
The method of using supercritical methanol in the production of biodiesel is unique because this
method does not require a catalyst. In the two stage supercritical method, methanol is brought to a
supercritical state at 250-300°C and 2.5-5 MPa. In the supercritical state, methanol is completely
miscible with the WCO; therefore, a catalyst is not required. This method of biodiesel production has a
large advantage over other reaction processes as it is able to convert any FFA in the WCO to biodiesel as
well without the need for pre-processing. A major disadvantage to the supercritical method is that a
large amount of energy is required to bring the methanol and WCO to the required reaction
temperature and pressure. The extreme conditions also cause difficulties in the design of the reactor to
handle these conditions. The supercritical method has great potential for being the most effective way
of producing biodiesel, but the temperatures and pressures required are outside of the scope of the
teams design for this project and they introduce an extreme level of danger (Vera).
10.5.2.6 Standard Tube Microreactor
A standard tube microreactor is essentially a miniature scale PFR type reactor. The extremely
small reactor tube diameter promotes the conversion of WCO to FAME by causing greater interfacial
area between the immiscible methanol and triglyceride reactants. They also allow for excellent heat
transfer to the reaction mixture due to the large amount of surface area. A single microreactor can
achieve near complete conversion to FAME but can only handle flow rates of roughly 0.1 gal/hr. To
achieve the goal flow rate of approximately 1 gal/hr, multiple microreactors would have to be purchased
or assembled, making them unsuitably expensive for use in the prototype design (Mazubert, Poux and
Aubin).
10.5.2.7 Acoustical Cavitation Reactor (ACR)
ACRs use ultrasonic waves to induce cavitation in the reaction mixture. Cavitation is best summarized by
the following description:
Cavitation is the generation, growth, and collapse of gaseous cavities, which causes the release
of large levels of energy in very small volumes, thereby resulting in very high energy densities. The
phenomena can occur at millions of locations in the reactor simultaneously, thereby generating
conditions of very high local temperature and pressures at overall ambient conditions.
-- (Mazubert, Poux and Aubin).
The cavitation phenomena promotes the mixing of the two immiscible liquid phases, thereby increasing
FAME conversion. ACRs can achieve very high conversions, but they must be purchased at a high cost
(Mazubert, Poux and Aubin).
10.5.2.8 Hydrodynamic Cavitation Reactor (HCR)
HCRs are similar in concept to ACRs but they use a physical geometry, like an orifice, to cause
cavitation in the reactor flow. HCRs have an advantage over ACRs in that they require less energy input
for operation but they have the same disadvantages, namely they must be purchased at high costs.
37
Additionally, HCRs require very high flow rates to achieve cavitation, eliminating them as a reactor
choice for the prototype design (Mazubert, Poux and Aubin).
10.5.2.9 Microwave Reactor
The use of microwaves reactors for the production of biodiesel is a recent development.
Microwave irradiation has two major benefits, no external heating is required and the catalyst efficiency
is significantly improved. Microwave irradiation is a highly efficient way to heat the reactor contents,
eliminating the need for another heat source. Microwave irradiation also encourages mixing on the
molecular level. This promotes transesterification of triglycerides with methanol, reaching near
complete conversion depending on which catalyst is used. Reports of 99% conversion in 10 seconds are
reported at high power outputs. Microwave reactors can be run in batch mode to allow for easy testing,
or they can be designed for continuous CSTR and PFR setups for the final prototype design. Batch and
CSTR designs require stirring which adds to the complexity. Much of the research performed illustrates
the use of household microwaves for reactor design, elimination the need for the purchase an expensive
reactor (Mazubert, Poux and Aubin).
10.5.2.10 Oscillatory Baffled Reactor (OBR)
OBRs are similar in design to a simple PFR, but they contain baffling in the reactor tube and they
function with an oscillatory or back and forth flow rate. The combination of these two features results in
increased mixing of the immiscible liquid phases present in the reaction mixture, contributing to high
FAME conversion in a short amount of time. Drawbacks to the OBRs are the complicated baffling design
and the requirement of a costly pulsed flow pump to achieve the oscillatory flow patterns (Mazubert,
Poux and Aubin).
10.5.2.11 Motionless Inline Reactor (MIRs)
MIRs, also known as static mixer reactors, are essentially a PFR with a stationary object put in
place to increase mixing of reaction products. Advantages of MIRs are the low cost of operation and
relative ease in design. Disadvantages are the moderately slow reaction rates, relatively low conversion
rates, size, and incompatibility with solid catalysts.
10.5.2.12 Membrane Reactor
Membrane reactors utilize an integrated membrane to separate desired reaction products, FAME,
from the undesired reaction products, glycerol, and the unreacted reaction feed, methanol, and
triglycerides. This promotes FAME conversion because the reaction equilibrium is shifted towards the
products. Membrane reactors also save on costs by integrating the separation step into the reactor
design. Disadvantages to a membrane reactor design are the slow reaction times, complicated design,
and high costs of construction (Mazubert, Poux and Aubin).
10.5.2.13 Reactive Distillation Reactor (RDRs)
As the name implies, reactive distillation type reactors combine distillation with a reaction
process. RDRs have been shown to produce excellent FAME conversion but their complexity and
required reaction conditions make them outside the scope of this project.
38
10.5.3 Design Decision
The Diesel Crew implemented a decision matrix, shown in
Table 10-4 and Table 10-3, to help determine which reactor type was best. The simple batch,
CSTR, PFR, and PBR reaction types were excluded from the decision matrix due to recent research that
determined the required FAME conversion cannot be achieved by these reactor types with a
heterogeneous catalyst at the chosen reaction conditions. For a more in depth comparison of the design
alternatives considered see Appendix A.
Based on the decision matrix, the team intends to commence testing of microwave reactors. If
initial tests of microwave reactors deems them unfeasible, the team will further investigate the
feasibility of using an oscillatory baffled reactor in our prototype design.
39
Table 10-3 Decision Matrix for Reactor Type
Reactor Type
Criteria
Decision
Weight Micro AC HC MB MC OB MI
C 10 2 2 4 10 8 5 8
CD 7 8 8 8 7 6 8 6
OC 5 8 3 5 2 2 4 7
OD 9 8 9 9 5 9 8 10
conv 8 10 6 8 10 8 9 9
t 5 10 9 7 2 7 3 2
T 9 7 7 7 7 7 7 7
P 9 10 10 10 10 10 10 10
PT 4 2 2 2 2 2 2 2
TP 4 2 2 2 7 7 7 7
Cat 15 5 5 5 5 5 5 5
SMC 15 0 3 3 7 7 7 2
FR 5 1 10 8 2 8 5 8
HT 5 7 5 5 10 10 5 5
Weighted Total 110 602 629 655 723 771 704 688
Normalized Score
(Higher=More Favorable) 5.5 5.7 6.0 6.6 7.0 6.4 6.3
Table 10-4 Summary of Abbreviations for Decision Matix in Table 10-3
Criteria Abbr. Reactor Type Abbr.
Cost C Microreactor Micro
Construction Difficulty CD Acoustical Cavitation AC
Operation costs OC Hydrodynamic Cavitation HC
Operation Difficulty OD Microwave Batch MB
Typical Fame Conversion conv Microwave Continuous MC
Reaction Time t Oscillatory Baffled OB
Operating Temp T Motionless Inline MI
Pressure P
Pretreatment of WCO PT
Treatment of Pdts. TP
Requires Catalyst Cat
Solid Metal Catalyst SMC
Flow Rate FR
Heat Transfer HT
40
10.6 Catalyst Recovery
A small but important part of the design is the ability for the system to reclaim the catalyst. This
is consistent with the team’s values of sustainability and stewardship. In addition by reclaiming the
catalyst, the potential costs of the system are decreased for the end user.
10.6.1 Design Criteria
The catalyst recovery unit should handle the required flow rate of the reactor and not clog
during the operation cycle. In addition the unit should be easy for the end user to replace and reclaim
the catalyst from the unit itself. Ideally the unit should be able to be replaced without shut down of the
entire system.
10.6.2 Design Alternatives
Although this portion of the design has not been extensively investigated yet, the team plans to
resolve this matter in the very near future. A few of the alternatives the team has proposed to test and
consider are discussed in the following sections.
10.6.2.1 Fine Wire Mesh
A fine wire mesh can be used in line with the system, as wire mesh is available in sizes as small as
2 microns. Wire mesh is easily replaceable; however, wire mesh may be expensive. An advantage of
using wire mesh is the ability for many different design shapes that can allow the team to meet the
criteria previously mentioned. Nevertheless, a drawback exists with the end-user being able to replace a
particular design with the wire mesh when the mesh design provided by this team is worn out.
10.6.2.2 Bag Filter
A bag filter would work very similar to the wire mesh with one significant advantage, the bag
filters come pre-manufactured and would be easily replaced by the end-user. Bag filters are available in
many different dimensions and pore sizes. Finally, a bag filter easily contains the catalyst particles upon
removal, but a design may be difficult to incorporate with changing bag filters without shutdown.
10.6.2.3 Diesel Filter
A normal petro diesel filter can be used as they are designed to keep out fine particulates that
could damage an engine significantly. These filters are nice as they work inline and are very durable, yet
a diesel filter may be difficult to change. Furthermore these filters are readily available to consumers
and are inexpensive to replace.
10.6.3 Design Decision
As the team has not investigated this portion of the design, no decision has been made. The
team plans to resolve the issue in the near future through experimentation and testing of the
alternatives listed previously.
41
10.7 Methanol Recovery
To help tilt the FFA and triglyceride reaction equilibria toward the desired FAME product, the
reactor feed is expected to contain significantly more methanol than the required stoichiometric
amount. As a result, the unreacted methanol should be recovered and recycled back into the reactor.
10.7.1 Design Criteria
Methanol recovery and recycle is desired for several reasons; the first of which is the produced
fuel’s quality. If unused methanol is left in the reactor effluent, the product will contain excessive low-
boiling methanol which would adversely affect the diesel combustion characteristics. The second reason
for methanol recovery is cost; at methanol:triglyceride ratios of 6:1 or greater in the feed, huge amounts
of unreacted methanol would be unnecessarily wasted, exhibiting poor stewardship. This would also
require a much larger fresh methanol feed storage tank, which runs contrary the stated goal of
producing a smaller reaction system. Furthermore, the excess methanol cannot simply be boiled off or
allowed to evaporate into the air, as methanol is a flammable, low-boiling (148.1°F per MSDS) toxic
substance (Safety-3), and thus poses an environmental and safety hazard. The final criteria used is the
ease of design and implementation. In the process of research, design, and development, time is a
limited resource and should be invested wisely.
10.7.2 Design Decision
Vacuum-Assisted Evaporative Distillation
In the design process, the Diesel Crew quickly decided to move away from using a batch reactor
with a liquid catalyst, which are two substantial departures from Rinnova’s 2008 design. As such, the
Diesel Crew anticipated spending large amounts of time developing the catalyst and reactor systems and
so elected to reuse as much of Rinnova’s methanol recovery system as convenience allowed.
Rinnova’s design utilizes vacuum distillation to evaporate the relatively volatile methanol off of
the reactor effluent, then using a water-cooled heat exchanger to condense the methanol into collection
vessels. The reactor effluent is generally fairly warm, resulting in a fairly, energy-efficient, safe
separation requiring only a little vacuum (<5 psig). As a sealed system there is little risk of methanol
escaping into the atmosphere, and no major problems were mentioned regarding the recovery system’s
operation in Rinnova’s final report (Rinnova). The team plans to implement the glass condenser they
obtained previously this semester (Figure 10-2).
Figure 10-2 Glass condenser Available to Use for Methanol Recovery
42
10.8 Separator
The reactor effluent consists of fatty acid methyl esters (FAME); methanol; glycerol; unreacted
mono-, di-, and triglycerides; and traces of catalyst. The reactor will be designed to with high enough
conversion to minimize the mono-, di-, and triglycerides remaining in the reactor effluent. The catalyst
recovery system should prevent catalyst from remaining in the product, while the methanol coming
from the reactor will be removed by a methanol recovery system as outlined in section 11.6. Much of
the glycerol produced from the reaction can be mechanically removed via a two phase, liquid-liquid
separator due to substantial differences in density compared to FAME (~1.26g/ml vs. ~0.88g/ml), but
further purification is needed to reach the high level of purity necessary to meet the ASTM standards,
which is accomplished by the final biodiesel purification system. The separator is necessary to avoid
clogging this final purification system with glycerol.
10.8.1 Design Criteria
The Diesel Crew needs a separator that effectively separates the glycerol from the biodiesel and
at low cost. Given that each triglyceride molecule converted into biodiesel produces one molecule of
glycerol, the separator needs to handle large quantities of glycerol without taking up undo space.
Preferably the separator is easy for the operator to service without needing specialized tools or training,
in keeping with the goal of maintaining a transparent design.
10.8.2 Design Alternatives
10.8.2.1 Settling Tank
A settling tank uses gravity to separate substances based on density. This is a low-cost, passive
system requiring little to no added energy other than that already possessed by the effluent. It may be
possible to perform glycerol separation co-currently with methanol recovery. Feasibility will likely
depend on the reactor flow rate and rate of separation, which dictate the size of the settling tank
needed for the glycerol to sufficiently separate from the FAME before leaving the settler.
10.8.2.2 Centrifuge
A centrifuge uses energy to separate substances based on differences in density, with the more-
dense liquid (in this case glycerol) pushed toward the outside of a cylinder via centrifugal force imparted
by a spinning rotor or by the cylinder itself rotating. Centrifuges have moving parts and thus will likely
both cost more and require maintenance more often than settling tanks; however centrifuges offer very
effective separation.
10.8.3 Design Decision
The Diesel Crew has not yet decided on a design for the separator, having tabled the decision
until the spring semester, when the reactor effluent composition, flow rate, and space requirements are
better known.
43
10.9 Biodiesel Purification
10.9.1 Design Criteria
After isolation of FAME from the reactor effluent in the separator and subsequent removal of
methanol, outlined in the previous sections, further purification is required to remove any remaining
contaminants. These contaminants include small amounts of FFAs, glycerol, mono-, di- and tri-
glycerides, and leached CaO catalyst. The biodiesel purification system must be capable of removing
these contaminants to levels low enough to meet all ASTM specifications. These specifications can be
seen in Figure 16-2 of Appendix D. Another criteria is that the purification be able to operate in a
continuous mode so that it is compatible with the chosen reactor design.
10.9.2 Design Alternatives
10.9.2.1 Ion-exchange Resin Column
An ion-exchange resin column, also known as a polishing column, can be used to remove the
glycerol and other contaminants from the FAME. Team Rinnova had great success using this technology
in the design of their reactor. The Rohm and Haas Company makes a resin called Amberlite™ BD10DRY
that is specifically designed for this separation. The Amberlite™ resin is prepared in a purification
column and the reactor products are passed through it. The polymer resin absorbs all of the glycerol and
impurities while allowing the FAME to pass though until the column becomes saturated. One pound of
Amberlite™ resin is able to purify 900 to 1600 pounds of biodiesel depending on the amount of
impurities. An added benefit is that this resin is able to be regenerated by a methanol wash cycle that
removes the glycerol from the column and returns the resin to its original state. Downsides to this
method of purification are the costs of the Amberlite™ resin at $72 a pound and the fact that soap,
catalyst and impurities other than glycerol will permanently poison the resin (DOW Chemical Company).
10.9.2.2 Water Wash
The most commonly used method for purification of FAME is a simple water wash cycle. The
wash cycle involves the rigorous mixing of distilled water with the biodiesel product and then
subsequent separation by heating or decantation based on differences in density. The water wash helps
to remove any remaining contaminants from the FAME. The advantage of this method over the others is
the low material costs of distilled water and separation vessel. Disadvantages include the difficulty of
transforming this process into a continuous design, slow cycle times due to the need for multiple wash
cycles, non-polar contaminants can be left behind in the biodiesel, high operating costs associated with
removal of all traces of water in order to meet ASTM specifications, and the cost associated with
treatment of the waste water (Suwannakarn).
10.9.2.3 Magnesium Silicate
Magnesium silicate powder is another method of separating impurities out of biodiesel.
Magnesol is the brand name magnesium silicate powder produced by the Dallas Group of America Inc.
for use in biodiesel purification. The Magnesol powder is added to the biodiesel crude product after the
methanol and glycerol separations have been made. After a brief period of stirring, the Magnesol forms
a gel with the polar contaminants which can then be easily filtered out. Advantages to purification with
44
Magnesol are that it is quick, relatively inexpensive at $92 for a 50 pound bag, and it removes a very
high level of contaminants. Disadvantages of Magnesol are that it is a consumable product, the filter
cake must be disposed of accordingly, and the difficulty of transforming this process into a continuous
design (Suwannakarn).
10.9.3 Design Decision
An ion-exchange resin column was chosen for the final biodiesel purification due to its ease of
operation, excellent contamination removal, and ease of integration into a continuous design. To further
assure that the produced biodiesel meets all ASTM specifications, an additional inline diesel filter will be
added after the polishing column for detainment of all resin material.
45
11 Preliminary Design
As shown in section 10, The Diesel Crew has and is evaluating several design alternatives, but at this
point in time certain common features are present in the design.
The reaction system will be housed on the steel frame from Pfizer.
HDPE Holding Tanks for WCO, MeOH, Glycerol, and Biodiesel Product
Input of WCO
Coarse wire mesh strainer and fine Ametek cartridge pre-filter to remove particulate from WCO
Immersion heater to remove water from WCO before fine-filter and reactor
Methanol and WCO feeds into reactor
Reactor uses calcium oxide catalyst to convert WCO to FAME
Catalyst is filtered/screened from reactor effluent
Methanol is separated from reactor effluent by vacuum distillation, is condensed and recycled
Glycerol is separated from reactor effluent
Biodiesel is polished via an ion-exchange column and final-filtered by an inline diesel filter
Pumps to change pressures and overcome gravity
Vacuum Pumps to lower pressure
Sample valves to collect data, perform tests, and troubleshoot
The PFD of the most recent design proposal is shown in Figure 11-1 as a continuous process.
46
P-34
P-1
Fine Filter
P-2
Water C
atch
Dewatering Vessel
P-4
P-7
P-8
Heater
P-10
Holding Tank For Course Filtered
Vegetable Oil
E-10
P-11
ScreenCatalyst Catcher
Course Filter
P-13
P-14
P-15
Oil Sampler
P-16
Fresh Methanol
Tank
P-17
P-18
V-3P-19
Sampler
P-20
P-21
P-22
Co
lum
n Sep
arator
P-23
P-24
Condenser
P-26
P-27
Methanol Vapor
Vaccum
P-28
Cooling WaterP-29
Glycerol Waste
P-30
Po
lisher
E-20
P-33
P-25
Sampler
Recovered MeOH
Storage
Methanol Recycle Pump P-35
P-36
Diesel Filter
P-38
P-39
P-40
BioDiesel Holding
Tank
Process Flow Diagram Updated December 8
Microwave Reactor Vessel
Figure 11-1 PFD Summary of Preliminary Design
47
12 Business Plan
12.1 Marketing Study
12.1.1 Competition
While there is a biodiesel plant in Bangor, MI, evidence (Blanco) suggests they primarily use
soybean oil for their feedstock; the other EPA-registered biodiesel plant in Michigan is in the Detroit
area (Weaver), and is thus unlikely to strongly compete with the planned company. Furthermore, as
most diesel fuel sold is petroleum-derived, suppliers of ordinary petro diesel, such as Crystal Flash, are
those the proposed company competes with.
12.1.2 Market Survey
12.1.2.1 Target market
The target market for this design are institutions such as Calvin College who not only produce a
significant amount of WCO from their kitchens, but also have a use for a bio diesel product. These
institutions do not have the resources to run a large industrial process, and only require a small amount
of diesel product. For this reason, the design must remain simple, and small scale. In order for these
institutions to be able to use the biodiesel, they must have modified engines in their vehicles or
machines such as lawnmowers. In fact, Calvin College does have both of these available and could make
good use of this design.
12.1.2.2 Customers' motivation to buy
There are numerous reasons why consumers will be motivated to buy biodiesel; the most
obvious reason being that biodiesel will be significantly cheaper than petro diesel.
Biodiesel has a higher oxygen content than petro diesel allowing for more complete combustion
resulting in lower emissions. Studies done by the U.S. Environmental Protection Agency (Agency)
discovered that when biodiesel replaces petro diesel, CO2 emissions are lowered by 78%. Even using B-
20 blends reduces CO2 by 15.6%. This makes biodiesel a very practical and economical way to address
climate change induced by greenhouse gas production. An additional benefit is the 100% reduction in
sulfur dioxide emissions, a particularly nasty greenhouse gas, when pure biodiesel (B-100) is used.
Additionally, biodiesel is easily incorporated into the existing petroleum based diesel infrastructure. The
standard biodiesel blend, B-20, consisting of 20% biodiesel can be stored in standard diesel fuel tanks
and pumped with conventional fuel equipment (Biodiesl Basics).
As a cleaner burning fuel, biodiesel is better for a car’s engine than conventional diesel,
providing greater lubrication and leaving fewer particulate deposits behind. No engine modifications are
required for the use of B-20 in cars and trucks produced since 1992. Biodiesel is biodegradable and
considered nontoxic by the Environmental Protection Agency.
All of these aforementioned benefits come at the cost of a measly 2% reduction in power output
when running on B-100 as compared to petro diesel (Biodiesl Basics). When using a B-20 mixture, the
reduction is essentially unnoticeable.
48
12.1.2.3 Market size and trends
2012 sales of distillate fuel oil in the transportation sector totaled 41,200,000,000 gallons in the
USA. Using the 2012 Retail Price of No. 2 Diesel in the Midwest, which has remained at $3.80 ±0.20 (U.S.
Energy information Administration) since March 2011, this yields a potential national market of $157
billion dollars/year (U.S. Energy information Administration). Within the Grand Rapids MSA
(metropolitan statistical area, population 1,088,514 as of 2013), (Dewey), this comes to $537
million/year via a simple per capita ratio. Since not all diesel vehicles on the road are currently rated for
B20 blends, B5 blends might have to serve those vehicles. As vehicle fuel systems develop, more
vehicles are anticipated to be covered under warrantee with B20 and higher blends of biodiesel, further
increasing the market. As a cautious approach though, at 15.6% B5 saturation, the biodiesel portion of
the $537 million/year comes to $4.20 million/year in revenue, although it is questionable if Grand
Rapids has enough waste oil to supply the 1.1 million gallons of B100 per year (3,021 gal/day) needed in
such a scenario.
According to the EIA (U.S. Energy Information Administration AEO2013 Early Release Overview),
even though light duty vehicle (LDV) transportation energy use is projected to go from 16.1 quadrillion
BTU’s in 2011 to 14.0 quadrillion BTU’s in 2025, diesel fuel consumption in Million barrels/day is
expected to rise by ~0.8 over 2011–2040 due to efficiency standards driving a move away from gasoline.
12.2 Cost Estimate
The production cost estimate for our project assumes the project is a “one-off” that will only be
built once. Because of this, the design work is the largest part of the cost. The team members’ hours on
the project will result in the completed prototype. So total labor for purchasing, research, design,
testing, building and so forth will all be calculated together at $100/hr for the hours put in by the team.
The basis for the hours spent on the project will be that at Calvin there is a maximum of four hours of
work and lecture a week per credited hour. For the fall there are two credited hours and three hours of
lecture a week, giving five hours a week of work for the fall semester per team member. The spring has
four credited hours with three hours of lecture a week, giving thirteen hours a week per team member
in the spring. Using a basis of fourteen weeks a semester, gives a total of 1,008 hours of total labor at
$100,800.
The cost for the prototype will be $2,247 as shown in Table 2-1. The feed stocks and catalysts
are all part of the research, development, and testing. The fixed costs total to $103,047. The variable
costs are outlined in Table 12-1.
Table 12-1 Variable Costs
Component Amount Cost
Methanol 55 gallons $195.00
Waste cooking oil 1 lb $0.05
Electricity kWh $0.073
Water 1000 gal $3.10
Waste Water Treatment 1000 gal $2.28 + $5.88 service charge
Labor Hr $100
Biodiesel Gallon -$3.50
49
-Utilities are from the City of Grand Rapids, MI
-Biodiesel calculated based on efficiency compared to petroleum diesel
-Purchased costs will be slightly higher
-A cost to produce a gallon of biodiesel is difficult to estimate without more development of the design
13 Conclusion
Extensive research has been done on the reactor portion of the system, leading to the
realization that obtaining high conversion at mild conditions with a continuous process is a challenge.
Microwave reactors have been found to be the most plausible solution, given the budget constraints of
the team. The next work in the design process will be testing the preliminary reactor design and finding
optimal operating conditions. Further steps in the spring will involve obtaining and optimizing the other
components of the system. The Diesel Crew will work to close the gap between budget and proposed
spending in that process.
50
14 Acknowledgements
The Diesel crew would like to thank the following organizations and people for their
contributions to this project this past semester.
Calvin College Engineering Department
-for the instruction from all the professors and advice on group management, and the technical
resources they have provided. In addition the Engineering Department provided a substantial portion of
the budget.
Professor Aubrey Sykes
-Professor Sykes was the team mentor for the senior design class. He communicated with the
team about current progress, giving suggestions on how to stay on task as well as technical advice when
needed.
Bob DeKracker
-Bob DeKracker was a significant resource in ordering major components and parts for the
construction of the prototype.
Bob Aupperlee
-Bob Aupperlee met with The Diesel Crew as an Industrial Consultant. He served as a third party
contact that can understand the scope and requirements of the project and give helpful critique and
concerns. The team met with Bob once this past semester, and anticipates meeting with him again in
the spring.
Chemistry Department
-The Calvin College Chemistry Department graciously allowed The Diesel Crew to use space in
the Organic Synthesis Lab for experimental work. In addition The Diesel Crew was allowed access to the
chemical stock of the department.
Professor Chad Tatko
-Professor Tatko was a significant help for the development of the methodology for HPLC
analysis. He found an unused HPLC instrument with an auto sampler for the team’s personal use. In
addition he served as a consultant regarding the chemistry of the system.
Rich Huisman
-Rich Huisman played a significant role in ordering materials for the team, specifically, the Fatty
Acid Methyl Esther standard, and the methanol. He saved the team a substantial amount of money
through his orders. In addition he helped locate various compounds to be used for the HPLC analysis.
Glenn Remelts
-Glen Remelts helped the team in the beginning of the year with initial research. He showed the
team the vast resources the Hekman Library has to offer, as well as purchased important research
articles for the team.
51
15 References
National Biodiesel Board. "The Biodiesel Standard (ASTM D 6751)." 2007. Biodiesel.
<www.biodiesel.org/resources/fuelfactsheets/standards_and_warranties.shtm>.
Advanced Organic Materials. "Fatty Acid Methy Ester MSDS." 2013. AOMSA.
Agency, U.S. Environmental Protection. A Comprehensive Analysis of Biodiesel Impacts on Exhaust
Emissions. October 2002.
Biodiesel Basics. 2013. November 2013.
Blanco, Sebastian. "Autobloggreen." June 2007. November 2013.
Dewey, Charlsie. Metro Grand Rapids population passes 1 million. Grand Rapids, March 2013. Article.
DOW Chemical Company. Rohm and Haas. 2012. Novemeber 2013.
European Committee for Standardization. "Biofuel Specifications." 2004. Biofuel Testing.
<www.biofueltesting.com/specifications.asp>.
Mazubert, Alex, Martine Poux and Joelle Aubin. Intensified processes for FAME prodcution from waste
cooking oil: A technological review. July 2013. PDF.
McNichols Industrial & Architectural Whole Product Solutions. 2010. December 2013.
<http://www.mcnichols.com/products/wire-mesh/>.
Refaat, A. A. "Biodiesel production using solid metal oxide catalysts." International Journal of
Environmental Science Technology (Winter 2011): 203-221. PDF.
Refaat, A. "Biodiesel Production Using Solid Metal Oxide Catalysts." International Journal of
Environmenal Science Technology (2011). Journal.
Rinnova. Final Report. Senior Design Report. Calvin College. Grand Rapids, MI: Harbert, Joshua; Ocier,
Christian; Kenyon, Mitch; Thielke, Fred; Alao, Adebo, 2008. PDF.
<http://www.calvin.edu/academic/engineering/senior-design/SeniorDesign07-
08/Team11/downloads.html>.
Science Lab. "Material Safety Data Sheet Listing." Dec 2013. Science Lab. Dec 2013.
<www.sciencelab.com/msdslist.php>.
Science Lab, Inc. Material Safety Data Sheet Potassium hydroxide MSDS. Houston: Scuebcelab.com,
Inc., 2013. MSDS.
Suwannakarn, Kaewta. "Biodiesel Production from High Free Fatty Acid Content Feedstocks." PhD
Dissertation. 2008.
U.S. Energy information Administration. December 2013. November 2013.
U.S. Energy Information Administration AEO2013 Early Release Overview. 5 December 2013. December
2013.
Vera, C. Production of biodiesel by a two-step supercritical reaction process with adsorption refining.
2010. PFD.
Weaver, Jennifer. Biodiesel Industry Overview and Technical Update. July 2013. Powerpoint.
Yang, Fangxia, Hanna A Milford and Runcang Sun. "Value-added uses for crude glycerol-a byproduct of
biodiesel production." Biotechnology for Biofuels (2012).
I
16 Appendices
Appendix A Reactor Research Summary
Table 16-1 Intensified Reactor Summary (Mazubert, Poux and Aubin)
Type of Reactor Microreactors Cavitation Reactors Microwave Reactors
Oscillatory Baffled
Reactors
Motionless Inline
Reactors
Specific Reactor Type
Standard Tube Microreactor
Acoustical Cavitation
Hydrodynamic Cavitation Batch CSTR PFR OBR
Reactor-Separator
Cost
High for required flow rates High High
Low for Low Volume
Low for Low Volume
Low for Low Volume Medium Low
Construction Difficulty
Easy- Purchased
Easy- Purchased
Easy- Purchased
Easy for Low Volume Medium Medium
Easy-Purchased Medium
Operation Costs
Low (only pumps required)
High (1000 watts)
Medium- req. energy input
High (9-1.1kW) 8-1.6kW 8-1.6kW Low Low
Operation Difficulty Easy Easy Easy Medium Easy Easy Easy Easy
Typical Conversion % to FAME 98- 99.9% 80-99% 95.00% 99-99.8% >97% >97% 99% 96-99%
Typical Reaction Time 0.5-6 mins 0.5 mins 10 mins
.17-
.66mins 0.5mins 0.5mins 30-40min 17.5-19mins
Operating Temperature
Methanol Reflux Temp (60-65°C) ambient 60C 60C ~60C 60C 40-50C
Operating Pressure ambient ambient ambient ambient ambient ambient ambient ambient
Pretreatment of WCO Required
Yes, removal of FFAs
Yes, removal of FFAs
Yes, removal of FFAs
Yes, removal of FFAs
Yes, removal of FFAs
Yes, removal of FFAs
Yes, removal of FFA
Yes, removal of FFA
Treatment of Product Required
Yes, washing of catalyst
Yes, washing of catalyst
Yes, washing of catalyst No No No No No
Requires Catalyst (y/n)
yes (liquid homogenous) yes (KOH) yes (KOH) Yes Yes Yes Yes Yes
Compatible with Solid Metal Catalyst No
yes(reduces particle size)
yes(reduces particle size) Yes Yes Yes Yes Not Tested
Typical Flow Rates 10-200 mL/hr 50-150 L/hr >50L/hr? 0 L/h
4.5-432 L/h
4.5-432 L/h
0.126-3.12 L/hr 72L/hr
Heat Transfer High/ External Source
Medium (external heating)
Medium (external heating)
High (internal heating)
High (internal heating)
High (internal heating)
Medium (external)
Medium (external)
Reactor specific Advantages:
Short Reaction Time
V. Short Reaction Time
V. Short Reaction Time
Low Reaction Time
Low Reaction Time
Low Reaction Time
Low Energy Input
Low Energy Input
Easy post-reactor separation
Ambient Temps.
Ambient Temps.
Helps Break Emulsions
High Flow Rate
High Flow Rate
Reactor specific Disadvantages:
Low Flow rates (10-200 mL)
Low Volumetric Rate
A Minimum Flow Rate Exists
V. Difficult to Scale Up
Difficult to Scale Up
Difficult to Scale Up
Requires Specialized Pump
Solids May Be A Problem
II
Appendix B Soy Oil Fatty Acid Distribution
Figure 16-1 FAME Molecular Weight Calculation for Soy Oil
III
Appendix C Fine Filter and WCO Temp Experiment
WCO is fairly viscous at ambient temperature, so Tom and Mike carried out an experiment to
test WCO flow through fine filters at different temperatures.
Materials & Equipment:
WCO (Soy oil) from Calvin College Dining Services’ WCO pit
Meijer brand coffee filters
Two 25mL graduated cylinders
Stirrer/Hot plate with beaker and stir bar
Thermometer
Stopwatch
Procedure:
A volume of 20.0 mL of WCO at one of several different temperatures was poured on a coffee
filter over a graduated cylinder, and the volume of flow through was measured after 2.00 minutes and
checked for particulate. New coffee filters were used for each trial. This procedure was then repeated
using two coffee filters stacked on top of each other rather than one.
Results:
Table 16-2 Results of Fine Filter Temperature Experiment
Number of Filters Temp (°C) Time (s) Volume (mL) Particulate in Pure
1
20 120 2 No Particles
30 120 6 No Particles
40 120 6.1 No Particles
60 120 12 No Particles
95 120 11 No Particles
2
30 120 3 No Particles
40 120 3 No Particles
60 120 6.8 No Particles
95 120 6 No Particles
The data shows, for both one and two filters, that increasing the temperature of the WCO
dramatically increases the ease of flow through the filters up to 60°C where the flow rate levels off. The
data also shows that the flow is inhibited by a factor of two when two filters are used rather than one,
and no particulate is found in the flow through at any temperature or number of filters in the ranges
tested.
Conclusion:
Testing flow of WCO through fine filters has shown that to increase flow through the filters, oil
doesn’t need to be heated to more than 60°C. The experiment has further shown that if coffee filters are
to be implemented as a fine filter, one coffee filter will achieve the same separation as two coffee filters
with half the inhibition to the flow. This trend might be applicable to all filters that separate by particle
size. The only thing the team would do differently if repeating the experiment is use volumes of WCO
greater than 20mL.
IV
Appendix D ASTM Specifications for B-100
Figure 16-2 ASTM Specifications for B-100