In Situ Recycling of Cleaning and Rinsing Fluids to Meet · PDF file ·...
Transcript of In Situ Recycling of Cleaning and Rinsing Fluids to Meet · PDF file ·...
The Science of Cleaning Green
In Situ Recycling of Cleaning and Rinsing Fluids to Meet Lean and Green Cleaning
Process Targets
By Steve Stach
Outline
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
Setting Cleaner Recycling Targets
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
Potential Savings
Water Saving – up to 99% reduction
Chemical Savings – 50-99% reduction
Energy Saving – 10-50% reduction
Waste Disposal – 50-90% reduction
What Cleaning Fluids Can be Recycled?
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
Choosing the Right Recycling Technology
1. It depends on the Solvent
2. It depends on what is happening in the solvent?
Alkaline/SaponifierWater/EmulsionOrganic Solvent
Reacting w/SoilsAccumulating Soils
Evaporation
Getting Started
Look at your “Mass Balance”
Mass Balance analysis
looks at all materials
entering and leaving the
cleaning process.
Shows where you are
loosing or gaining
fluids/ingredients
Cleaning Mass Balance Diagram
Fluid Tank
Recycling System
CleaningSystem
Waste
Fluid Feed,Make-up
Mist-EvaporativeAnd Drag-Out Losses
w/soils
Parts
Cleaning Fluid With SoilsSewer or Disposal
Identify & Understand Your Recycling MethodRecycle Method Type Used with Waste stream Waste disposal
handler
System
Complexity
level
Safety concern
Chemical
addition
Additive
Key Ingredient
1) Reactive
Aqueous
Mixtures
(saponifiers)
Soil loaded tank
dump
Company Technician Medium
Ion Exchange Subtractive
Adsorption
Rinse water
Alcohols
Glycols
Esters
Depleted DI
resins
Third party Operator Low
Carbon
Adsorption
Subtractive
Adsorption
Rinse water Carbon media
with organics
Third party Operator Low
Zeolite
Absorption
Subtractive
Adsorption
NPB
CFC’s
HCFC’s
Zeolite with
adsorbed
contaminate
Third party Operator Low
Chelation Subtractive
Adsorption
Water with heavy
metals
Chelation media
with heavy
metals
Third party Operator Low
Distillation Subtractive
Distillation
NPB
CFC’s
HCFC’s
Non volatile
residues
Company Technician High
Filtration Subtractive
Filtration
All fluids Filters with
contaminate
Company Technician Medium
Reverse
Osmosis
Subtractive
Filtration
Rinse water Reject fluid
stream
Company Technician Medium
Cleaning Fluid Recycling Choices
Cleaning/Rinsing Agent Adsorption Distillation Filtration Replenish
Ingredient
Water Only Recommend Not Used Used Not Used
Water Neutral Not Used Not Used Used Recommend
Water Alkaline Not Used Not Used Used Recommend
Organic Non-flammable Used Recommend Used Not Used
Organic Combustible Recommend Used Used Not Used
Organic Flammable Recommend Used Used Not Used
H2OIPA
CoolPrec.
NPB
Additive Recycling Technologies
Key Ingredient Replacement
Common in aqueous mixture to replace drag out or reactive losses
Saponifing agents
Degreasing stabilizers
Subtractive Recycling Technologies
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
Fluid Filtration
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
Fluid Distillation
Boiling fluid is vaporized and condensed
High boiling soils are left behind for disposal
Recommended for non-flammable, single solvents or azeotropicsolvent blends
Not usually recommended for water or flammable solvents
Ion Exchange
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
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 Absorption
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
Carbon Absorption
Carbon Absorption VS Compound
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
Closed Loop Inline Cleaning System
TurbineMixedGAC
Carbon
1g/m 1g/m
FilterMΏ
Reverse Osmosis (RO)
RO is most commonly used for feed water
generation to closed loop cleaners
RO typical removed ~90% of dissolved solids
from tap water
Reverse Osmosis
Molecular sized microscopic pores block large molecules and allow smaller molecules to pass
Turbine
Gravity Drain
High Alarm
Add
Low Alarm
High Alarm
Add
Low Alarm
Mixed
Dryer DI Rinse Power Rinse Chem Isolation Wash
GACCarbon
Chempump
Incoming Tap/RO waterFeed to fill tanks
Initial and Make-upOperational .Flow @120F=
3gal/hr estimated
1g/m 1g/m
Filter MΏ
~25gallons ~40gallons
Problem Heavy Metals in DI/GAC media
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
Molecular Sieve Absorption
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
Molecular Sieve Absorption
Useful in removing water, flux residues, and
most ions from organic cleaning solvents
35X 700X 4,500X
Use of Molecular Sieve
Molecular Sieve filters to remove contamination from
Degreasing Solvents
Organic solvents
The Impact of the Recycling Location
The Impact of the Recycling Location
Here, There or Anywhere?
TurbineMixedGAC
Carbon
Chempump
1g/m1g/m
FilterMΏ
~25gallons
In Situ(in the cleaner)
Plant System(in the factory)
Third party(bonded & licensed)
Off-site Treatment of Cleaning Materials
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
In-plant Recycling of Cleaning Fluids
Distillation and Evaporation
Check with local air quality authorities
A permit may be required
Central DI Plant
What materials are use?
Source, new or regenerated?
In Situ Recycling of Cleaning Fluids
Built in, or Next to the Cleaner
No transfer logistics
Minimizes heat loss
Fewer Parts
Local Control
Requires training
Operator
Maintenance
Costs less to Operate
Equipment costs less than stand alone
Lowest operating costs
The Cost of Cleaning
Building the Cost Model
Indep
Inline Cleaner Cost ModelProcess 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) ?????????? ???????? ????????
Bed Life (hrs of operation)
Capacity of Close Loop Absorptive Beds
Depends on the Ion
Molecular weight & valance
Tank Absorptive Capacity (Abtotal)
Bed Volume (Vab)
Absorptive Capacity (Abcap)
(Abtotal) = (Abcap) X (Vab)
Estimating the Life of Absorptive Beds
Contamination Feed Rate
Mass Flow Rate (MFrate)
Bedlife = (Abtotal / MFrate)x %factor*
* %factor is % available in beginning + % remaining at exhaustion
US map showing water hardness
Building the Cost Model
Indep
Inline Cleaner Cost ModelProcess 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
Cleaning Cost Estimates
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
Summary
Government and industry are driving recycling
Cost and environmental benefits provide the rewards for conversion
Cleaning mass balance analysis provides data to start
Summary
All cleaning solvents can be recycled
There are many methods of recycling
Your clean solvent guides you recycling method
Summary
Recycling reduces process costs
The location of the recycling system can affect
cost.
In situ recycling is the most cost effective
Conclusions
If you are not recycling your cleaning fluids, you
should be!
“In Situ Recycling of Cleaning and Rinsing Fluids to Meet Lean and Green Cleaning Process
Targets”by
Steve Stach