In Situ Recycling of Cleaning and Rinsing Fluids

In Situ Recycling of Cleaning and Rinsing Fluids to Meet Lean and Green Cleaning Process Targets By Steve Stach President Austin American Technology

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 p. H – 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/Saponifier Water/Emulsion Organic Solvent Reacting w/Soils Accumulating 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 Feed, Make-up Parts Mist-Evaporative And Drag-Out Losses w/soils Recycling System Fluid Tank Cleaning System Waste Cleaning Fluid With Soils Sewer or Disposal

Identify & Understand Your Recycling Method Recycle 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 Water Neutral Not Used Recommend Water Alkaline Not Used Recommend Organic Non-flammable Used Recommend Used Not Used Organic Combustible Recommend Used Not Used Organic Flammable Recommend Used Not Used H 2 O IPA NPB Cool Prec.

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 – 1 to 10 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 nonflammable, single solvents or azeotropic solvent blends • Not usually recommended for water or flammable solvents

Ion Exchange • Ionic soils are captured by ion exchange resins • Cations (Na+, K+, NH 3+) are removed by cationic exchange resins • Anions (OA-, Br-, CO 3 -) 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

Carbon Absorption • 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

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 VS 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. 196 95. 6% Butyric acid 88. 1 ∞ . 119 59. 5% Ethylene glycol mono butyl ether 118. 2 ∞ 0. 112 55. 9% Test solution 1 g/liter

Closed Loop Inline Cleaning System Filter. MΏ GAC Mixed Carbon Turbine 1 g/m

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

Incoming Tap/RO water Feed to fill tanks Initial and Make-up Operational. Flow @120 F= 3 gal/hr estimated Dryer DI Rinse Power Rinse Chem Isolation Wash Chem pump Filter MΏ GAC Carbon Mixed Turbine High Alarm Add Low Alarm ~25 gallons 1 g/m Gravity Drain Inline Cleaner - closed loop wash and Rinse Back View - Plumbing diagram ~40 gallons

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 35 X 700 X 4, 500 X

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? Chem pump MΏ GAC Filter Mixed Turbine Carbon ~25 gallons 1 g/m 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 Process Data Inline Open Loop Closed Loop Central System Varib Equipment cost $200, 000 DI system cost $25, 000 $35, 000 $5, 000 Shipping $5, 000 $4, 000 Water consumption rate gph (operating) 300 10 10 Cost of water $'s/gal $0. 01 Cost to regenerate DI (1. 5 Ft 3) $300. 00 $500. 00 Water purity (dissolved solids) mg/gal 250 20 20 Final rinse rate GPM 5 5 5 Power cost $s/Khr $0. 10 Operating KW (KV*A) 100 110 75 7 year equipment amortization 6 Run time per Shifts per year Process Costs ($'s/hr) Absorbtive capacity (mg Ca. CO 3 or Succinate) Bed Life (hrs of operation) Inline Cleaner Cost Model 300 ? ? ? ? ? In Situ Closed Loop ? ? ? ?

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 US map showing water hardness • Contamination Feed Rate – Mass Flow Rate (MFrate) Bedlife = (Abtotal / MFrate)x %factor* * %factor is % available in begining + % remaining at exhaustion

Building the Cost Model Indep Process Data Inline Open Loop Closed Loop Central System Varib Equipment cost $200, 000 DI system cost $25, 000 $35, 000 $5, 000 Shipping $5, 000 $4, 000 Water consumption rate gph (operating) 300 10 10 Cost of water $'s/gal $0. 01 Cost to regenerate DI (1. 5 Ft 3) $300. 00 $500. 00 Water purity (dissolved solids) mg/gal 250 20 20 Final rinse rate GPM 5 5 5 Power cost $s/Khr $0. 10 Operating KW (KV*A) 100 110 75 7 year equipment amortization 6 Run time per Shifts per year Process Costs ($'s/hr) Absorbtive capacity (mg Ca. CO 3 or Succinate) Bed Life (hrs of operation) Inline Cleaner Cost Model 300 In Situ Closed Loop 1, 680, 000 7, 900, 000 3. 7 219. 4

Cleaning Cost Estimates Inline Open Loop Annual Cost of beds OL DI, CL DI+GAC Hourly Cost of beds Hourly cost of tap water Closed Loop Central System In Situ Closed Loop $144, 642. 86 $4, 101. 27 $80. 36 $2. 28 $3. 00 $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 Thank You for Attending Questions ? ? ? ?