recycling of cleaning fluids to meet green cleaning process · pdf file ·...
TRANSCRIPT
Recycling of Cleaning Fluids to Meet
Green Cleaning Process Targets
By
Steve Stach
Austin American Technology
Setting recycling targets? Paying for recycling? What can be recycled? Review of the 4 basic types of fluid recycling
Absorption
Distillation
Filtration
Replenishment Estimating the cost and saving
Estimating system life
Cost Model review
Government Regulations
Few direct mandates
Significant cost/liability regarding waste;
i.e. generation, storage, transportation, disposal
Corporate Directives
Avoid liability by not generating
Cut manufacturing expenses
Marketing “Green Manufacturing” sells product
Water Saving – up to 99% reduction Chemical Savings – 50-99% reduction Energy Saving – 10-50% reduction Waste Disposal – 50-90% reduction
Just about everything! Water
Tap, DI Water Mixtures, Neutral pH
Buffered aqueous mixtures Water Mixtures, Alkaline
Emulsions, Homogenous mixtures Organic, nonflammable
Halogenated solvents Organic, combustible
Glycols, oils, esters Organic, Flammable
Alcohols, light hydrocarbons
1. It depends on the Solvent
2. It depends on what is happening in the solvent?
Alkaline/Saponifier
Water/Emulsion
Organic Solvent
Reacting w/Soils
Accumulating Soils
Evaporation
Recycle
Method
Used with Waste stream Waste disposal
handler
System
Complexity
level
Safety concern
Chemical
addition
Reactive
Aqueous
Mixtures
(saponifiers)
Soil loaded
tank dump
Company Technician Medium
Ion Exchange Rinse water
Alcohols
Glycols
Esters
Depleted DI
resins
Third party Operator Low
Carbon
Adsorption
Rinse water
Carbon media
with organics
Third party
Operator Low
Zeolite
Absorption
NPB
CFC’s
HCFC’s
Zeolite with
adsorbed
contaminate
Third party
Operator Low
Chelation Water with
heavy metals
Chelation media
with heavy
metals
Third party
Operator
Low
Distillation NPB
CFC’s
HCFC’s
Non volatile
residues
Company Technician High
Filtration All fluids Filters with
contaminate
Company Technician
Medium
Reverse
Osmosis
Rinse water Reject fluid
stream
Company Technician
Medium
Identify & Understand Your Recycling Method Recycling System Choices
Cleaning/Rinsing Agent Adsorption
Distillation Filtration Replenish
Ingredient
Water Only Recommend for
high purity
Rarely Used Recommended for
General use
Not Used
Water + additive, Neutral pH Not Used Not Used Recommended for
General use
Recommend
Water Alkaline Not Used Not Used
Recommended for
General use
Recommend
Organic Non-flammable Used Recommend Recommended for
General use
Not Used
Organic Combustible Recommend
Used
Recommended for
General use
Not Used
Organic Flammable Recommend
Used
Recommended for
General use
Not Used
H2O
IPA
NPB
Key Ingredient Replacement
Common in aqueous mixture to replace drag out or reactive losses
▪ Saponifing agents
▪ Degreasing stabilizers
Filtration
Use of filters to remove soils
Distillation
Removes contaminates with higher boiling points
Absorption
Use of Carbon, DI resins, Zeolites and other Media to Adsorb contaminates
One of the oldest recycling methods Configuration
Cartridge, Bag, Plate, Cake Filter Size
1to10 micron typical Design Type
Mono or Multi-Filament
Absolute vs Standard Recommended uses
Used in most closed or open loop cleaning systems
Boiling fluid is vaporized and condensed
High boiling soils are left
behind for disposal Recommended for non-
flammable, single solvents or azeotropic solvent blends
Not usually recommended for
water or flammable solvents
Ionic soils are captured by ion exchange resins Cations (Na+, K+,NH3
+) are removed by cationic exchange resins
Anions (OA-, Br-,CO3
-) are removed by anionic exchange resins
Mixed Beds remove both Anions and Cations Recommended for purifying water and most organic
solvents Not recommended for solutions containing amines
RO is most commonly used for feed water generation to closed loop cleaners
RO typical removed ~90% of dissolved solids from tap water
Absorptive medias capture metal ions Cations (Pb+2, Ag+2,Cu+2) are captured by
cationic exchange resins GAC can do the same Use new GAC and DI media or find
regenerator with metal cheatlation system
A molecular sieve traps molecular soils in microscopic pores.
Naturally occurring materials are referred to as zeolites
Man made materials are called molecular sieve. Molecular sieve comes in different pore sizes
ranging from 3 to 12 angstrom Commonly used as a desiccant Available in round or extruded pellets
Useful in removing water, flux residues, and most ions from organic cleaning solvents
35X 700X 4,500X
Organic soils are captured by Granular Activated Carbon (GAC)
Works on basis that “Like
attracts Like” Capacity depends on the
molecule Often used in conjunction with
DI closed loop systems Carbon Exhaustion Foams Rinse
GAC is made by anaerobic heating organic material to drive off all volatiles
Most GAC is acid washed to remove acid soluble impurities
Coconut shell and anthracite coal are two type that product low powdering
GAC can be partially regenerated by steam stripping – not recommended
Compound Mole Weight Water
Solubility %
Adsorption g
soil/ g GAC
Adsorption %
reduction
2-ethyl butanol 102.2 0.43 .170 85.5%
Mono-ethanol
amine
61.1 ∞
.015 7.2%
Di-ethanol
amine
105.1 95.4 .057 27.5%
Nitro-benzene 123.1 0.19 .196 95.6%
Butyric acid 88.1 ∞ .119 59.5%
Ethylene glycol
mono butyl
ether
118.2 ∞
0.112 55.9%
Test solution1g/liter
Mass Balance analysis looks at all materials entering and leaving the cleaning process.
Shows where you are loosing or gaining fluids/ingredients
Fluid Tank
Recycling
System
Cleaning
System Waste
Fluid Feed,
Make-up Mist-Evaporative
And Drag-Out
Losses
w/soils
Parts
Cleaning Fluid
With Soils
Sewer or Disposal
The impact of the recycling location
Turbine Mixed GAC
Carbon
Chem
pump
1g/m 1g/m
Filter MΏ
~25gallons
In Situ
(in the cleaner)
Plant System
(in the factory)
Third party
(bonded & licensed)
The Local Sewer Plant Check with local water authorities A permit may be requires
The DI Guy
What materials do they use? ▪ Source, new or regenerated?
How do they dispose of the waste?
Solvent Recycler/Disposal Use EPA licensed & bonded company Cradle to grave responsibility
Indep
Inline Cleaner Cost Model Process Data Inline Open Loop
Closed Loop
Central
System
In Situ Closed
Loop
Varib Equipment cost $200,000 $200,000 $200,000
DI system system cost $25,000 $35,000 $5,000
Shipping $5,000 $5,000 $4,000
Water consumption rate gph (operating) 300 10 10
Cost of water $'s/gal $0.01 $0.01 $0.01
Cost to regenerate DI (1.5Ft3) $300.00 $500.00 $500.00
Water purity (dissolved solids) mg/gal 250 20 20
Final rinse rate GPM 5 5 5
Power cost $s/Khr $0.10 $0.10 $0.10
Operating KW (KV*A) 100 110 75
7 year equipment amortization
6 Run time per Shift
300 Shifts per year
Process Costs ($'s/hr)
Absorbtive capacity (mg CaCO3 or Succinate) 1,680,000 7,900,000 7,900,000
Bed Life (hrs of operation) 3.7 219.4 219.4
Depends on the Ion Molecular weight & valance
Tank Absorptive Capacity (Abtotal)
Bed Volume (Vab) Absorptive Capacity (Abcap)
(Abtotal) = (Abcap) X (Vab)
Contamination Feed Rate
Mass Flow Rate (MFrate) Bedlife = (Abtotal / MFrate)x %factor* * %factor is % available in begining + % remaining at exhaustion
US map showing
water hardness
Inline Open
Loop
Closed
Loop
Central
System
In Situ
Closed Loop
Annual Cost of beds OL DI, CL DI+GAC $144,642.86 $4,101.27 $4,101.27
Hourly Cost of beds $80.36 $2.28 $2.28
Hourly cost of tap water $3.00 $0.10 $0.10
Power costs/hr $15.00 $16.50 $11.25
Total Power and water cost $/hr $98.36 $18.88 $13.63
Equipment Amortization cost per hr $16.43 $17.14 $14.93
Total Equipment + Water + Power ($/hr) $114.79 $36.02 $28.56
Saves
$85/hr
All cleaning solvents can be recycled
There are many methods of recycling
Your clean solvent guides you recycling method
Government and industry are driving recycling
Cost and environmental benefits provide the rewards for conversion
The savings are easy to estimate with a good mass and energy balance diagram