ePOH Inc.

Consultants:Hope Baumgarner

Tyler GibsonWes HudkinsJoseph Nick

Josh Stephens

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc.

Overview:

• Based on our findings for project 3, the addition of the cyclohexane unit is not profitable

• Large price increase in cyclohexane would be required to make process profitable

• Current market value Cyclohexane: $4.10/gal

• For process to be profitable price would have to be 5 times the current market value

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Economic Analysis:

• Total Capital Investment: TCI = FCI + WC =$4,690,000

• Fixed Capital Investment: FCI = DC + IC = $3,640,000

•Annual Product Cost: $243 MM to $357 MM when a 4% inflation rate is taken into account

•Process considered profitable when ROR > 8%

•Annual Cash Flow: CF = (S-C) x (1-Φ)+dΦ

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Economic Analysis:

•Annual Cash Flow:

Price of Cyclohexane Annual Cash Flow

$2.05 ($ 1.29 Billion)

$4.10 ($608 MM)

$20.50 $4.82 Billion

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Economic Analysis:

•Net Present Worth: Criterion used to determine profitability

•Payout Time: Time required to recover investment• Positive values indicate that investment will be

recovered • Negative values indicate investment will not be

recovered

•Return on Investment: Describes how much money is earned per dollar invested

• When ROI>ROR the process is profitable

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Economic Analysis:

Selling Price Cyclohexane

POT ($/yr) ROI (%) NPW

$2.05 ($0.02) (22.4) ($846 MM)

$4.10 ($0.05) (10.7) ($402 MM)

$20.50 $0.01 83.4 ($3.15 Billion)

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications

• Mixer & Splitter: • Diameter = 4.9 ft• Height = 19.6 ft• Volume = 185 ft3

• Material: Carbon Steel

• Cost included in the piping cost• Heat Exchangers:

• Shell & Tube • Carbon Steel tubes and shell

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications:

Heat Exchanger 1 Heat Exchanger 2 Heat Exchanger 3

Fluids Light organics/light

organics

Steam/ light organics

Steam/medium organics

UA (BTU/hr-m2-°F) 88,900 19,550 61,300

Design Value, U (BTU/hr-°F)

660 1040 850

Surface Area (m2) 134 19 72

Cost $18,000 $2,200 $8,000

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications:

Flash Tank: • Vertical liquid gas gravity settling separator

• Cross sectional area: 57 ft2

• Tank Diameter: 9 ft

• Cost: $81,000

Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications:

Reactor: • Tubular reactor• 30 tubes

• L= 20 ft• OD = 3 inches

• 40% of the cross sectional area dedicated to tubes• Cost: $9,000

Compressor: • Power Requirement: 53 kW• Adiabatic Efficiency: 80%• Type: Centrifugal• Cost: $80,000Project 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications:

Distillation Column, Condenser & Reboiler:

• Size based on estimated superficial velocity for flooding to occur

• Operation 80% of vapor speed

• Based on Perry’s Chemical Engineer’s Handbook it suggest that about 15% of total cross sectional area be devoted to downcomer envelope

• Number of Trays: 28

• Reboiler: Specified as a kettleProject 3

ePOH Inc. Addition of a Cylcohexane Production Process

to Independent Refineries Inc

Equipment Cost & Specifications:

Distillation Column, Condenser & Reboiler: • Column Cost: $140,000

• Condenser Cost: $40,300

•Reboiler Cost: $515,600

• Total Cost: $781,400

Project 3

ePOH Inc. Fluid Transport and Economic Analysis

• Design of the pipe network• Stainless Steel• Currently operating at unsafe pressures

• Pipes need to be increased to schedule 80• Piping dimensions proposed by IRI found to be less

than optimal• ePOH’s recommendations could save $500,000

• Adding fiberglass insulation will decrease NPW by $1 million

Optimal piping costs for cyclohexane production plant

Piping w/ Insulation $764,120

Valves $65,000

Elbows $4,000

Installation $366,350

Total $1,200,000 Project 4

ePOH Inc. Fluid Transport and Economic Analysis

Two-phase flow

• Pro II was used to determine what flow regimes are inside the two-phase flow pipes in the process

• The Reynolds number was calculated for single phase flow from the thermodynamic parameters given by Pro II, and then the flow regimes for the two-phase streams were taken from the simulation report

• All the single-phase streams are in the turbulent flow regime, and all the two-phase flow streams are in the stratified wavy flow regime

Stream Re Flow Regime

Hydrogen 317000 single-phase turbulent

Benzene 95300 single-phase turbulent

Recycle 605000 single-phase turbulent

Feed 59800 single-phase turbulent

Top 215000 stratified wavy

Bottom 72500 single-phase turbulent

Purge 202000 stratified wavy

S1 2800000 stratified wavy

S2 2480000 stratified wavy

S3 2350000 single-phase turbulent

S4 2140000 single-phase turbulent

S5 83200 stratified wavy

S6 46900 stratified wavy

S7 11800 stratified wavy

S8 9450 stratified wavy

Project 4

ePOH Inc. Fluid Transport and Economic Analysis

Pressure Drop in Streams

• Pressure drops in the pipes are much smaller than the overall pressure gradient in the system

• Current compressor pushes the stream up to 500 psia while they exit the system at atmospheric pressure

• There is no need to add additional pumps and compressors to overcome the pressure drop in the pipes

Stream Type Length (ft) ΔP (psi)

Hydrogen 8’’ Sch 40 700 0.0059

Benzene 4’’ Sch 40 500 0.89

Recycle 8’’ Sch 40 350 0.0062

Feed 6’’ Sch 40 150 0.102

Top 8’’ Sch 40 500 0.00018

Bottom 6’’ Sch 40 500 0.129

Purge 6’’ Sch 40 300 0.00139

S1 10’’ Sch 40 150 0.0165

S2 10’’ Sch 40 100 0.0148

S3 10’’ Sch 40 150 0.0278

S4 10’’ Sch 40 150 0.0229

S5 10’’ Sch 40 100 0.0195

S6 10’’ Sch 40 150 0.0413

S7 10’’ Sch 40 150 0.0027

S8 10’’ Sch 40 100 0.00291

Project 4

ePOH Inc. Fluid Transport and Economic Analysis

• Performed risk analysis on the cyclohexane unit• High risk, very low return• Less than 20% chance of breaking even• The difference between cyclohexane (product) and

benzene (raw material) would need to increase to $1.51/gallon

• ePOH does NOT recommend constructing the cylcohexane unit• Could use Diels Alder reaction as an alternative way to

produce cylcohexane

H2, Pt

Project 4

ePOH Inc.

NPSHA vs. Flow Rate

0 200 400 600 800 1000 1200 14001380

1390

1400

1410

1420

1430

1440

1450

1460

1470

1480

Flowrate (ft3/hr)

NPS

HA

(ft)

Project 5

ePOH Inc.

System Head vs. Flow Rate

0 200 400 600 800 1000 1200 14000

50

100

150

200

250

Flow Rate (ft3/hr)

Syst

em H

ead

(ft)

Project 5

ePOH Inc.

Pumping section PFD

Project 5

ePOH Inc.

Reactor Specifications

Reactor Material Chosen: Type 304 Stainless Steel

Advantages of material:

• resist to corrosion

• high alloy metal

• very high tensile strength

Project 5

ePOH Inc.

Piping and Insulation Specifications

Piping Insulation

Material selected

Type 304 stainless steel Fiberglass

(chosen to resist corrosion)

(low thermal conductivity)

Thickness n/a 1-2.5 in.

Bursting Strength

62,000 kPa n/a

Cost $1,800 ---

Project 5

ePOH Inc.

Pump Specifications

P u m p

Centrifugal pump - chosen due to its low cost and ease of maintenance

Work needed 5.98 Hp

Pressure gain 117.7 psi

Head 360.5 ft

Cost ~ $3,000

Project 5

ePOH Inc.

Pumping Section: Fixed Capital Investment

Centrifugal Pump Cost $3,000

Piping Cost $1,800

Total Material Cost $4,800

Installation Cost $2,250

Total Cost (2002) $7,050

Total Cost (2009) $7,500

Project 5

CH-Plant: Heat Exchanger StudyePOH Inc.

M1 E1

E2

F1

SP1

C1

R1

E3

BENZENE

HYDROGEN

S3

S5

S4

S6

S7

S9 S10

S11

S12

S13

S1

500 psig

Eff. 80%

Purge Gas

Product

DP=15 psi

300 F

120 F

Recycle

E2

E1

E3

Project 6

ePOH Inc.

Heat Exchanger: Hand Design

•Exchanger E1 designed for two cases: Single-Pass Tubes Double-Pass Tubes

•Equipment cost determined for each design

•T-Q Diagram compared

Project 6

ePOH Inc.

Outer Diameter of Tubes (ft) 0.75

Length of Tubes (ft) 12

Pitch (Square) (ft) 0.08

Number of Tubes 500

Area (ft2) 1,165

Shell Diameter (ft) 2.12

Heat Transfer Coefficient (Shell Side)

(Btu/hr-ft2-F)

15.2

Heat Transfer Coefficient (Tube Side)

(Btu/hr-ft2-F)

1.40

Outer Diameter of Tubes (ft) 0.75

Length of Tubes (ft) 12

Pitch (Square) (ft) 0.08

Number of Tubes 920

Area (ft2) 2,160

Shell Diameter (ft) 2.80

Heat Transfer Coefficient (Shell Side)

(Btu/hr-ft2-F)

55.3

Heat Transfer Coefficient (Tube Side)

(Btu/hr-ft2-F)

1.38

Single-Pass Tubes Double-Pass Tubes

Project 6

ePOH Inc.

T-Q Diagrams: E1 Single-Pass Tubes Double-Pass Tubes

0 1 2 3 4 5 6 7 8 9 100

50

100

150

200

250

300

350

400

450

500

0

50

100

150

200

250

300

350

400

450

500

T-Q Diagram

Cold Stream

Hot Stream

Q (MMBTU/hr)

Tem

pera

ture

(°F)

0 1 2 3 4 5 6 7 8 9 100

50

100

150

200

250

300

350

400

450

500

0

50

100

150

200

250

300

350

400

450

500

T-Q Diagram

Cold Stream

Hot Stream

Q (MMBTU/hr)

Tem

pera

ture

(°F)

Project 6

ePOH Inc.

Heat Exchanger: Rigorous Model•Rigorous heat exchanger model used for exchanger E1•Tube length and diameter and shell diameter were varied to produce the smallest heat transfer area•Designed using Pro II Process Simulator

* Minimize heat transfer area to Minimize cost!

Project 6

ePOH Inc.

Heat Exchanger: Rigorous Model

Square Pitch236 tubes, each 16 feet long1275 ft2 heat transfer area11,600,000 Btu/hr heat duty

Project 6

ePOH Inc.

Heat Exchanger 2 and 3

Designed using the simple heat exchanger models with Pro II

Project 6

ePOH Inc.

Cost of Heat Exchangers

Number

Exchangers

Purchased

Cost /

Exchanger

Total Purchased

Cost (2002)

Total Purchased Cost

(2008)

3 $30,830 $92,490 $133,160

Purchased Cost of all

exchangers$133,160

Total FCI of all

exchangers$388,830

Project 6

ePOH Inc.

Cyclohexane Tower Dimensions7 feet in diameter, 56 feet tall28 trays inside column2 foot spacing between columnCondenser duty: -3,300 Btu/secReboiler duty: 3,700 Btu/sec

• Column sized assuming vapor velocity is 80% of that required for flooding from the following correlation:

Project 6