CASE STUDY #4 - Solvent for Parts Washer. Problem Summary:

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1 1 CASE STUDY #4 - Solvent for Parts Washer Problem Summary: Clear-Loc Fastener Company uses 16 screw and stamping machines to produce fasteners for the aircraft industry. In between every other machine is a barrel-mounted parts washer. These parts washers are used to clean gross stamping oils off manufactured parts and to clean components of the machines themselves. The parts washers contain mineral spirits, delivered and taken away by a rental service. The solvent's flashpoint is below 140 degrees F, therefore it is manifested as a hazardous waste. The volume of solvent waste manifested is significant. Existinp Equipment: Eight parts washing stations, consisting of barrel mounted wash sinks and submersible recirculating pumps. The pumps pull solvent from the barrel and discharge it through a hose. The hose terminates in a small brush assembly, used to speed cleaning. There is a rack and basket in each wash sink, to hold small parts and facilitate draining. The Process: When a basket of processed parts is full, it is removed from the screw machine by an operator, and allowed to drain into a trough. The stamping oil which collects in this trough is circulated back into the screw machine for reuse. After draining, the basket is placed into the parts washer, and the parts are hosed down with solvent. The basket is then left to drain in the parts washer for 5 to 10 minutes. After draining, the parts are blown off with compressed air and sent to the packaging area. Most of the mineral spirits has evaporated by the time the parts are sent to packaging. Any slight film which may remain on the parts is viewed as a "preservative", to be removed by the customer at a future time. Produced by EOEML of the Georgia Tech Research Institute and the Pollution Prevention Assistance Division of the Georgia Department of Natural Resources

2 2 CASE STUDY #4 - Solvent for Parts Washer, continued SDecial Considerations: The parts washing tanks and the parts washers (sink and drum, along with all hardware) are owned by the rental service, which services the units every four weeks. The contract with the service calls for the solvent in each parts washer tank to be changed out on each service visit. Although the solvent waste is manifested by Clear-Loc, they do not have to handle the tanks or change out the spent solvent. All of this is done by the rental service. This hands-off program is viewed as an advantage by Clear-Loc management and shop floor personnel. The solvent rental service charges $50 per tank, per changeout. Each tank holds about 20 gallons of solvent. The total amount of hazardous solvent manifested out of the facility as waste last year was 15,000 pounds. Economic Considerations: The $400 per month rental fee is viewed as a mixed blessing by the facility. Management likes the "hands-off" nature of the service, but recognizes that all 8 tanks may not actually be spent at the 4 week interval. Facility Considerations: This is a standard metal working facility, which does not have any advanced waste or wastewater treatment equipment at this time. Some consideration was given to purchasing distillation equipment to clean the stamping oils, but the idea was never pursued. Workforce Considerations: The workers at Clear-Loc are on a profit sharing program. They are interested in saving the company money, but they receive little guidance on environmental or source reduction matters from management. There is no designated environmental compliance person, SO the Safety Director handles environmental compliance issues. Produced by EOEML of the Georgia Tech Research Institute and the Pollution Prevention Assistance Division of the Georgia Department of Natural Resources

3 I trough Dupont Case Study #4-Page 1 PROPOSAL FOR CASE STUDY ##4- Solvent Parts Washer Key Customer Need: Reduce both the expenses incurred by a solvent rental service and volumes of hazardous waste disposed of. Proposed Cleaning Asent: A hydrocarbon based cleaning agent with a flash point above 140 degrees F that contains an ester additive it increase performance under heavy soil loading conditions. Proposed Process: The proposed process would be similar to the existing process with the exception that the cost conscious workers need to minimize the amount of stamping oil introduced into the cleaning solvent. This can be done by blowing off oils from the parts basket while in the or shaking the basket periodically while the oil is draining OK An additional, weekly check of the specific gravity of all the wash sink sumps would be performed to determine the oil loading. Any sumps at a predetermined level would be changed out. Excess solvent on the parts would dry less rapidly, but this was viewed as a "preservative". Equipment Required: No additional equipment except for a hydrometer. Environmental Aspects: Waste solvent would no longer be manifested as hazardous waste and could be disposed of relatively inexpensively as waste fuel oil (possibly with existing stamping oils).

4 Dupont Case Study #4-Page 2 PROPOSAL FOR CASE STUDY ##4- Solvent Parts Washer, continued Benefits to Customer: The potential for lower cleaning costs is dependent on increasing the operatlmalife o.he cleaning agent to reduce both purchase and disposal quantities. Critical to this is minimizing stamping oil drag in to the wash sinks and monitoring the sink sumps so that they are replaced only when needed. There are two main reasons using the proposed cleaning agent will extend the useful life of the sink sumps. First the solvent starts out cleaner - it is free of all oils. The rental solvent has been recycled via distillation and contains some amounts of contaminates left over from it's "previous life". Higher oils loading levels with acceptable cleaning is possible due to the inclusion of the ester co-solvent. A new sink sump of the proposed cleaning agent will start out a more effective cleaner and, as stamping oil levels increase, degrade in performance more slowly than simple mineral spirits. This results in acceptable cleaning at higher contaminate levels which mean longer times between sink sump replacement.

5 . OCS Systems Case Study f4. CASE STUDY #4 - Solvents for Parts Washers - Solution! The O.C.S. NFH2002 would be used in this instance. O.C.S. NFH2002 is a biodegradable, non-toxic, non-flammable, non-combustible, aqueous cleaner. It meets the South Coast Air Quality Management District's VOC requirements. It can, and is used in the barrel mounted wash sinks. The phosphate in the product prevents corrosion and is easily removed. In the process, the oil could still be drained into a trough, but a much better method is to put the parts in a spinner. This removes and saves even more of the stamping oil. Because the company is using a rental service, it would have to purchase its own parts washers, and those would preferably be heated, and stainless steel. They run from $ to $ each. The O.C.S. NFH2002 would be used at an 8:l to 1O:l dilution ratio and be heated to 100 F to 110 F. The parts would be cleaned in the existing manner, hosed down or using the brush. The parts would then be blown off with compressed air. The companies that use services from a solvent rental company seem to forget that they, the company that uses the solvent are responsible from the cradle to the grave. If that rental service company happens to "lose" a drum picked up from the user, the user is responsible. The O.C.S. NFH2002 and the removed contaminates have been given sewer discharge approvals in many cities, because of its biodegradability, but O.C.S. does not recommend this, and more and more cities want zero discharge. O.C.S. recommends ultra filtration, such as the Membrex system. The company would use the O.C.S. NFH2002 in the parts washers until heavily contaminated, then the used cleaner would be put in a holding tank, run through the Membrex ultra filtration process which would remove most of the oils. The cleaned solution would be returned to the parts washer. This saves water and the O.C.S. NFH2002. The only addition of the O.C.S. would be maintaining the 8:l to 10: 1 dilution ratio. This is lost mainly through evaporation and residue being blown off of the parts. The purchase of new equipment is certainly an economic consideration, but the actual cost of the O.C.S. NFH2002 when diluted would be $1.50 to $1.35 per gallon. With the company being able to save more prod&t than it would use, it should realize a return on investment in about 2 years. Cost per tank per change out could be as little as $5.00 to $25.00, depending on whether the company uses the closed loop (Membrex) system or not. Also, more money would ultimately be saved by recovering more of the stamping oils. The ultra filtration unit is compact, reasonably priced and would not interfere with the facility. The only drawback with the whole process is that a worker would have to be assigned to change out the parts washer equipment and to process the solution. In the end the safety, health, environment and the economic issues have all been handled to the advantage of the user company.

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7 Orange Sol, Inc. '' Case Study IIk-Page 1 CASE STUDY #4 - Parts Washer Summary Clear-Loc Fastener Company has a number of options available in the market, including alternative solvents, aqueous systems, and different equipment designs and ownership arrangements. Our recommendation has two components; replace the solvent that is currently used, and utilize improved parts washer equipment. Fundamental Issues The issues of significance in replacing the solvent at Clear-Loc are: Maintaining the ability to clean the parts Eliminate or reduce the hazardous waste that must be manifested. Currently, 2000 gallondyear of hazardous (low flash point) solvent must be manifested, generating related direct and hidden costs. Recommendation Our two-part recommendation includes an effective solvent that will remove the machining and other soils, and equipment that acts to concentrate contaminants and maximize solvent life. The solvent choice (a proprietary blended cleaning agent) has a proven record of performance in this type of cleaning task. It contains no hazardous components, and is considered non-toxic, which should meet with the approval of the Safety Director at Clear-Loc. Field evidence has indicated that workers prefer the odor of this product over mineral spirits, allowing good user acceptance levels. The flash point of this product is over 160"F, taking it well out of the hazardous range. The equipment preference is a parts washer designed to allow the collection of a concentrated contaminant slurry, so the bulk reservoir solvent remains cleaner. The solvent is also pumped through a filter system before being directed onto the parts to be cleaned. As a result, solvent life is greatly extended, and only dragout makeup is required. Regular maintenance on the machine (contaminant trap operation and filter replacement) is extremely simple, and can be done in-house in a few minutes. While this is not quite the "hands off" situation they have now, it is very close. This system requires considerably less attention than an aqueous system or a parts washer that needs regular "total volume" servicing. The solvent blend has a lower evaporation rate than mineral spirits, so the flash point tradeoff is that the drying of parts will take slightly longer. In addition, a capital expenditure may be required to buy the machines (although these units are considerably less expensive than most aqueous units). Of course, equipment leasing arrangements can be made if the capital expense is a problem.

8 Orange Sol, Inc. Case Study #4-Page 2 CASE STUDY #4 - Parts Washer Page 2 Occasional purchases of a drum of solvent will be necessary to repiace dragout, and periodically replace an entire reservoir (in this type of operation, an 18 month life is reasonable). From time to time, Clear-Loc must dispose of spent product and filters, which would probably not be considered hazardous products (assuming they don t use chlorinated metalworking oils and aren t machining any exotic metals) and could be incinerated. Conclusion Clear-Lac Fastener Company has a cost-effective option that improves the environment for workers as well as effectively minimizing hazardous solvent handling/manifestation and the related expenses.

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11 EZE Products Inc. ' < Case Study 84 CASE STUDY #4 CLEAR-LOC FASTENER COMPACT MINERAL SPIRIT REPLACEMENT ONCE AGAIN AN AQUEOUS SYSTEM WILL NEED TO BE COUPLED WITH EQUIPMENT FOR THE BEST RESULTS. A MILD MULTI-METAL SPRAY CLEANER WITH A SPRAY WASHER HAVING A BRUSH ATTACHMENT FOR DIFFICULT PIECES HAS SUCCESSFULLY REPLACED MANY PARTS WASHING STATIONS. SINCE THE PRODUCT USED IS A SPRAY WASH TYPE, OIL SEPARATES READILY FROM A QUIESCENT TANK. THE CLEANER PORTION IS BIODEGRADABLE ALLOWING FOR DISCHARGE TO POW WITH PROPER DOCUMENTATION AND PERMITTING. LITERATURE ON THE DEVICE DESCRIBED IS ATTACHED.

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13 ., Petroferm, Inc. Case study #4 Case Study 4: Solvents for Parts Washer Petroferm Inc. The Problems There are only a few problems identified by this case study. They include: I. treating water from an aqueous process; 2. hazardous waste disposal; 3. operational cost of any alternative process; and 4. limited capital availability. Summary From the information given in the case history background, this company is presently spending only $50 per tank per month. They are said to be interested most of all in the minimum cost solution. No employee is assigned personal responsibility for environmental comp I iance. There are a number of ways to accomplish the required cleaning task with materials of lower hazard and/or lower environmental impact than mineral spirits. But all of them will cost more-maybe substantially more--and there is no clear requirement to change from the current method. As long as the company and its employees are not concerned with an annual hazardous waste production rate of 15,000 pounds, particularly as long as there is no additional charge from their current supplier for properly disposing of that waste, there does not appear to be any performance- or economics-driven reason for them to replace their present system. Some things are hard to improve much.

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15 *. OxyChem Case ~tudy t4 Case Study #4: Solverit fur Parts Washer While each of the OXSOL solvents can be used as a cold cleaning solvent in a solvent degreasing station, OXSOL 73 will provide the greatest solvency at the lowest price, and will allow employees to follow their same cleaning routine. Like traditional oxygenated, or flammable solvents, OXSOL 73 can be economically reclaimed in an explosion proof still. (OXSOL 73 is composed of a both flammable and non-flammable components, but is non-flammable to boiling in its blended form). Reclaimed efficiencies of greater than 95% are capable. By investing in a thinfilm evaporator or still with steam stripping capabilities, efficiencies closer to 99% are possible. Stills can be purchased in any size to accommodate the necessa work load. Spent solvent can be collected at the end of the day, week, or month for reclaiming. 't; y purchasing an explosion proof still, spent solvent can be re-used continuously. Oegreasing wastes can be condensed, filtered to remove insoluble matter, and also reused if necessary. Customers who purchase their own still for use with OXSOLs can realize a tremendous cost savings by reclaiming their own degreasing wastes. If requested, OxyChem Technical Service personnel can provide safety and handling seminars to OXSOL customers. In addition, our Regulatory Affairs group can keep customers informed of up-to-date regulatory changes that affect their business.

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17 Case Study 84 - Page 1 SOLVENT CLEANERS FOR THE WORLD CASE STUDY #4 - SOLVENT FOR PARTS WASHER Terpene Technologies offers parts washers with Tarksol" HTF and HTF-40 to industry as a replacement for mineral spirits and 140 solvent. The Tarksol" solvents have flash points greater than 212OF. We are currently supplying many Fortune-500 companies and the automotive aftermarket with environmentally safe parts washers and water based solvents. After three months of use in the parts washers with the complementary filtration and oil magnet, the spent Tarksol" passed the TCLP Test and is not considered a hazardous waste. Application testing shows Tarksol" environmentally safe aqueous solvents perform better than mineral spirits on most types of soils and grease. A 16% solution of Tarksoln HTF-40 will last 12 weeks before the parts washer must be recharged. The economic considerations are as follows: TERPENE TECHNOLOGIES, INC Midtown Tower Rochester, New York (716)

18 SOLVENT CLEANERS FOR THE WORLD 8 parts washers x 20 gals gals solution 160 gals x 16% HTF Gals HTF Gals HTF-40 x $16.44/gal = $427.44/3 months $ $142.48/month Non-hazardous waste pickup: 160 gals/3 months x $0.50/gal = $80.00/3 months $ $26.67/month Total cost per month for solvent and disposal: Total cost of parts washers - (8): 3 years: $ $ $ each x 8 - $4, $4, months - $133.1l/month Total cost per month for solvent/disposal/parts washers: $ $ Clean-LOC Fastner Company is currently paying $ per month, Tarksol" would save the company $47.74 per month and they would have a totally environmentally safe degreasing operation. TERPENE TECHNOLOGIES, INC Midtown Tower Rochester, New York (71 6)