CASE STUDY #5 - Spot Maintenance of Motors & Electrical Equipment. Problem Summarv;

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1 CASE STUDY #5 - Spot Maintenance of Motors & Electrical Equipment Problem Summarv; Southern Power Company operates 5 power generating stations in the Southeastern US. Three of the plants bum coal, the other two are hydro powered. Two to three times per year, several of the generators are taken off line for maintenance. During this maintenance, a significant amount of solvent is used for soil removal. Additionally, a variety of small motors, windings, breakers, and switchgear are maintained on a regular basis. The primary soils encountered at Southern Power are coal dust and carbon as well as grease and heavy lubricants. Historically, 1,1,1 trichloroethane has been used as a maintenance solvent. Utility management has recently become aware of this widespread use of 1,1,1 trichloroethane. In order to prepare for the upcoming phase out of ozone depleting solvents, the environmental staff has begun to search for acceptable alternative cleaners. Existine Equipment; Equipment being cleaned ranges from generator turbines, rotors, windings, and rotor blades to smaller electrical parts. These parts can range in size from 50 feet in diameter by 20 foot high to just a few inches. Because of their size, parts are primarily cleaned in-place using 1,1,1 trichloroethane, dispensed from a 55 gal drum with a pressure sprayer. Since this method creates a significant amount of hazardous waste, floor supenisors have discouraged the use of 1,1,1 trichloroethane from the drum. The cutback in the use of drums has resulted in a dramatic increase in the use of 1,1,1 trichloroethane in aerosol cans. The largest generating station used over 12, ounce aerosol cans last year. 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 #5 - Spot Maintenance of Motors & Electrical Equipment, continued The Proces Equipment is simply sprayed with the 1,1,1 trichloroethane until the operator perceives that all of the soil has been flushed from the apparatus. In many ways, this process resembles sandblasting except the blast media is chlorinated solvent, not sand. Since the solvent is dispensed at high pressure (the cans are pressurized to 90 psi), the solvent does not have a great deal of time to act. It is really the force of the liquid on the surface which dislodges the soils. After "blasting" the blast media and the soil fall to the ground, where the solvent evaporates and the soils are mopped up and disposed of. Since the perception is that the solvent is "gone" after aerosol use, little attempt is made to capture the small amount of remaining waste. Spec ial Cons iderations: The equipment being cleaned is primarily energized or soon to be energized. Voltages can exceed 46,000 volts. For this reason, water based cleaners, which may become entrapped in the motor or windings, are difficult to use. Unless management could be shown that there is no risk of any water remaining on the equipment, water could not be used. Any cleaner which will leave a conductive residue also cannot be used. Economic Considerations: The cost of any environmentally preferred replacement is not of great concern, as long as it meets the technical requirements set forth by the utility. Produced by EOEML of the Georgia Tech Research Institute and the Pollution Prevention Assistance Division of the Georgia Department of Natural RcM>ums

3 3 CASE STUDY #5 - Spot Maintenance of Motors & Electrical Equipment, continued Facilitv Cons iderations: Approximately 50% of the equipment is cleaned in place. There is little room to move or maneuver this equipment. Smaller components are often taken to an electrical shop, which is located in the main building of each plant. These shops have poor ventilation and no sewers or running water. Workforce Co nsiderations: Maintenance in the utility industry is always performed quickly, because a non-producing generating plant costs its owners money every hour it is down. The workers are used to being able to grab an aerosol can of 1,1,1 trichloroethane and get their work done. They are not well educated about the impending phase out of 1,1,1 trichloroethane. Any replacement will have to be implemented along with some sort of user education program to support the transition. Produced by EOEML of the Georgia Tech Rcsearch Institute and the Pollution Pnvcntion Assistance Division of the Georgia Department of Natural Rcsourccs

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5 Eco 1 ink ' Case Study #5-Page 1 Ecolink Environmentally Preferred Solutions FocIndustry CASE STUDY #5 - Spot Maintenance of Motors / Electrical Equipment The Problem The widespread use of aerosol 1, 1, 1 trichloroethane has been recognized and acknowledged as a problem at the Southern Power Company. The use of aerosol Ill,I trichloroethane as a "liquid sandblast medium" is quick and convenient, and not viewed by the workers as much of an environmental problem, (the solvent evaporates completely and leaves no visible "waste"). Unfortunately for the satisfied 1, 1,I trichloroethane users at Southern Power, December 31, 1995 will be the last day of ozone depleting 1, 1, 1 trichloroethane production in the developed nations of the World. If the corporations manufacturing these substances follow European trends, they may discontinue manufacture of chlorinated solvents well before the 1995 drop-dead date. This means that products widely used at the Southern Power Company for solvent cleaning and Non Destructive Testing will soon be unavailable. A variety of chlorinated solvents can be found in products traditionally used in the power generation community. While the case study cites degreasing as the main use of aerosol 1,I, 1 trichloroethane, our experience with the power generation community indicates that aerosol cans of 1,I, I trichloroethane (TCA) are also widely used in various stages of non-destructive testing. TCA is used in pre cleaners, post cleaners, solvent removers, some penetrants and developers, as well as in many popular dielectric solvents. Some chlorinated solvent ingredients in formulated products are not ozone depleters, but they are being severely regulated due to toxicity and other undesirable characteristics, (methylene chloride and perchloroethylene). Many users of aerosol 1, 1, 1 trichloroethane are unaware of the impending loss of a product or products they have taken for granted for a long time. Others have been led to believe that these products may not be casualties of this latest environmental crusade. The reality is that the environmental, health and safety tide has turned, and these products will soon be gone for good. Now it is time to consider replacement options. continued on page two A DIVISION OF SENTRY CHEMICAL COMPANY

6 Ec o 1 ink Case Study 115-Page 2 CASE STUDY #5 - Spot Maintenance of Motors / Electrical Equipment Page two The Solution Some manufacturers are promoting flammable solvents as an alternative to nonflammable chlorinated solvents. The flammable hydrocarbons, (mineral spirits, alcohol, hexane, other aromatics or blends of the above), appear to work like chlorinated solvents; they dry quickly after application and they remove many of the same soils. However, the use of highly flammable products raises serious safety questions. Commonly accepted OSHA, NFPA and industrial safety practice would lead the user to conclude that these low-flashpoint cleaners, (most in the 800 F. range, some as low as 350 F.), present an unacceptable safety risk. This risk is compounded by the fact that these products are predominantly sold in small pressurized aerosol cans, creating quite an explosion hazard! In order to narrow our search and locate a verifiably acceptable environmentally preferred alternative, it may be helpful for us to narrow our focus by identifying some criteria for the selection. Some of the requirements that should help us in our search for alternatives follow. Our alternative should exhibit as many of these properties as possible: 1. A high PEL (preferably greater than 350 PPM, based on TCA) 2. A flashpoint above 1400 F. TCC (EPA's cutoff for ignitable material) 3. No residual contaminant, per ASTM for TCE Solvent 4. An evaporation rate that is as at least as fast as stoddard solvent 5. No carcinogenic, mutagenic or teratogenic ingredients, (Le.; no glycol ethers) 6. Aggressive enough to remove cutting oil, transformer oils, grease, dyes 7. Not harmful to painted surfaces 8. Mild odor 9. No hazardous or listed ingredients, causing disposal problems. As a general guide we can also refer to content evaluation standards used by the power generation industry. These are the limits placed on several specific contaminants, if the fluid is to come into contact with steam or combustion turbines and generators: Total Halides 500 ppm Max. Total Chloride 100 ppm Max. Total Sulfur as SO4 500 ppm Max. Mercury 1.O ppm Max. continued on page three

7 Ecolink Case Study #5-Page 3 CASE STUDY #5 - Spot Maintenance of Motors / Electrical Equipment Page three Emerging from these requirements, a new option has recently gained prominence as an environmentally preferred alternative for those using TCA in the power generation community. ECOLINK's ELECTRON Environmentallv Preferred Dielectric Solvent, has emerged as the product standard in this category. ELECTRON has won technical approval from a variety of organizations including Westinghouse Power Generation Service Division, General Electric Apparatus Service, the Army, Navy and Air Force. After testing numerous proposed alternatives, Westinghouse PGSD has selected ELECTRON as its solvent of first choice. ELECTRON, a blend of highly refined organic terpene and very pure aliphatic hydrocarbons is a safe, effective solvent for use in electrical maintenance and Non Destructive Testing applications. ELECTRON has a flashpoint of 1470 F TCC, evaporates completely and leaves no residue to interfere with power transmission or penetrant application and inspection. The terpene component provides exceptional solvency, enabling the user to quickly and easily remove all types of soils and penetrant, (insuring low background after penetrant removal). In order to meet the rigorous performance standards stated above, the terpene component of the solvent must be distilled or somehow purified to remove impurities normally found in d-limonene and other organic solvents. Citrus terpene has become a popular component of many janitorial and industrial cleaners. Virtually all of the citrus or pine terpene used in these janitorial-type formulations is made with commercial terpene, which is not suitable for use in critical cleaning applications. While undistilled terpene may be fine in those products, only distilled terpene, (free of surfactant additives), is acceptable for use in blends intended for critical maintenance or NDT. The Process ELECTRON is available in aerosol and bulk form. It may be used much like the aerosol 1, 1, 1 trichloroethane, with two new features taken into account: The slower dry-time and the combustibility. Compared to chlorinated solvents, terpene/hydrocarbon blends dry more slowly. The average rate of evaporation, (when the terpenelhydrocarbon blends are properly formulated), is times slower than 1, 1, 1 trichloroethane. Therefore a short drying step may need to be inserted into the cleaning procedure. This drying can be accomplished by, "warming the parts in drying ovens, with infrared lamps, forced hot air, or exposure to ambient temperature". (ref.: ASTM E 165, Section 8.4.2). If the environmentally preferred solvent is applied in moderation, the dry time can be comparatively rapid. A few moments wait or a quick blast of compressed may be all that is necessary to speed drying. - continued on page four.. 1.

8 Ecolink Case Study il5-page 4 CASE STUDY #5 - Spot Maintenance of Motors / Electrical Equipment Page four As for the combustibility, ELECTRON has a Tag Closed Cup flashpoint of 147 OF., making it a combustible. At 147 O F, the closed cup flashpoint makes this blend considerably less dangerous than the flammable solvents discussed earlier. When measuring flammability in closed cup testers, the reading is reflective of the temperature that the liquid must reach before it emits any combustible vapor. Therefore, the terpene/hydrocarbon liquid would have to be fairly hot before a combustible vapor would be present. The main area of ignition concern develops when the material is wicked onto rags. Since ELECTRON does not evaporate quickly, rags are often an integral part of the process. These rags act as a wick, and are subject to ignition, just as a cigarette lighter wick will catch fire when saturated with lighter fluid. Proper management of rags is an important part of the process modification when switching from a non-flammable hazardous solvent to and environmentally preferred ignitable material. The tradeoff is the absence of hazardous waste generation and the elimination of toxic fumes. Since the need to replace 1,I,I trichloroethane is no longer an optional decision, but a mandatory task, we believe the drawbacks in using a hydrocarbon/ terpene blend are outweighed by the benefits. Facilitv / Environmental Considerations ELECTRON and other terpene/hydrocarbon blends, like all hydrocarbons are classified as VOC's. VOC's or Volatile Organic Compounds are one of the precursors of smog, and major cities can restrict the emission of VOC. These restrictions normally impact industries engaged in the spraying of paints or coatings and do not, as a rule impact small point source users of less than 10 aerosol cans per day. Nevertheless care should be taken to use terpene/hydrocarbon blends judiciously to avoid excess VOC emissions. ELECTRON is quality controlled to meet or exceed the dielectric requirements of Southern Power, as specified in the case study. Depending on the ASTM measurement method used, ELECTRON carries a dielectric strength up to 54,000 volts. continued on page five

9 I Ecolink Case Study #5-Page 5 CASE STUDY #5 - Spot Maintenance of Motors / Electrical Equipment Page five The issue of ventilation was raised in the case study. Hydrocarbon/terpene blends can be irritating to the nasal passages and throat. If ventilation is not present, there will be problems when ELECTRON is sprayed. On the other hand, it is difficult to believe that aerosol 1, 1,I trichloroethane was used in a poorly ventilated area with no problems. While the use of ELECTRON without adequate ventilation may cause discomfort, it is not a chronic toxin, and is not associated with long term health effects. In any event, adequate ventilation must be provided to insure worker comfort. Conclusion A majority of the power geneiation facilities in the US have switched from aerosol 1, 1, 1 trichloroethane to ELECTRON Environmentallv Preferred Dielectric Solvent. While this is not a miracle product or a panacea, it does meet the technical needs of today's maintenance engineer. It may be used to replace aerosol 1, 1, 1 trichloroethane for general dielectric cleaning or for non-destructive testing. ELECTRON carries many technical approvals, including an Air Force QPL listing: MIL-I & E. A diligent program of worker re-education and training is a critical part of the success story associated with this environmentally preferred alternative technology. The positives and the negatives of this transition must be explained to the workforce. Support should be made available to insure that users technical questions are answered. As with other process changes, it is always helpful to offer support to those who are concerned or offer resistance. Users of I, 1, 1 trichloroethane must understand that this solvent will soon be gone. Now is the time to be proactive and implement the best available alternatives, to insure maintenance program continuity. For further information: Tom Womack 404/ end -

10 (. Orange Sol, Inc. Case Study il5-page 1 CASE STUDY #5 - Motor/Electric Maintenance Summarv Southern Power Company s goal to eliminate Ozone Depleting Compounds in their facilities can readily be achieved, and the employee work environment be simultaneously improved. Although there are more exotic options, we recommend a high dielectric propriety solvent blend, available in either drums or aerosol cans. Fundamental Issues The issues of importance to the management and employees of Southern Power Company appear to be: The management and environmental staff desire to eliminate ODCs The equipment being cleaned might be energized up to 46kV. Some soils (coal dust and carbon) require physical removal, not just solvency About half of the cleaning is performed in a poorly ventilated electrical shop The workers have a need for solvent information/education None of the spent solvent is recaptured. Recommendation We recommend a proprietary blended cleaning agent, formulated for (and currently used in) exactly this kind of application. The product contains no ODCs, and has a dielectric strength greater than the energized level of the electrical equipment. This electrical cleaner is available in aerosol, or can be used in pressure sprayers, to provide physical as well as solvent action. The product has a much lower vapor pressure and more agreeable odor than 1,1,1 Trichloroethane, and contains no listed hazardous components. This will improve worker safety, especially in the poorly ventilated electrical shop, The workers at the 5 power generating stations need some sort of user education program regarding solvents. As the supplier, we would assist in preparing and presenting such a seminar.

11 ~ Vrange bol, Lnc. Case,Study #5-Page 2 CASE STUDY #5 - Motor/Electric Maintenance Page 2 Compared directly to 1, 1,l Trichloroethane, this product has lower volatility and will not evaporate as rapidly. As a result, it is likely that there will be puddles of solvent and soil on the floor, which will require mopping (instead of the soil alone). The collected mixture can be allowed to settle, and the solvent decanted off and reused. Conclusion The Southern Power Company management and environmental staff can eliminate ODCs by a number of means. This solution not only maintains effective cleaning, but also increases the safety of workers exposed to the solvent spray or vapors... c

12 OxyChem Case Study #5: Spot Maintenance of Motors & Electrical Equipment Problem To perform the same duties as 1,1,1, a solvent with special physical properties is needed. The solvent must be aggressive enough to remove contaminants, yet not so aggressive that it chemically attacks the plastic and other non-metal components in the generating station. While it readily dissolves the greases and heavy lubricants, 1,1,1, like most organic solvents, does not dissolve or readily remove coal and carbon dust unless the application provides a mechanical cleaning action to help the solvent. Presumably, 1,1,1 was most effective when used in an aerosol application. The replacement solvent should also be useful in both aerosol spray or wipe on applications. With the increasing environmental awareness of today's society, there comes a stronger commitment to responsibility among industry - especially those who produce and use chemicals. It is no longer acceptable to allow potentially hazardous products to "harmlessly" fall to the round and evaporate. While it is true that most of the 1,I,1 used for cleaning at Southern Power 80. installations evaporated to the atmosphere, some may be entrained in the soil. Eventually these solvents can leach to water sources, and potentially cause harm to the surrounding environment. Proposed C lean ina C h em is trv/equ i pm e n t p-chlorobenzotrifluoride (PCBTF) is an excellent example of a solvent that posses "selective solvency". Like 1,1,1, it is very good at dissolving oils and greases without attacking most other non-metal parts. In compatibility tests with plastics and elastomers, many common plastics used in construction were not chemically attacked by PCBTF, including epoxy and ABS. In a compatibility test with electronic circuit boards, PCBTF was very efficient at removing contaminants, yet did not chemically attack the circuit board components. PCBTF has a Kauri-Butanol value of 64, which is about twice the solvency strength of mineral spirits. With the use of an appropriate propellant, it can be used similarly to 1,1,1 as a spray on degreaser. Unlike 1,1,1, OXSOL 100 is an inherently stable product. It can be packaged in an aerosol can without the need of a stabilizer package to protect the can from corrosion. Like 1,1,1, PCBTF is an organic solvent, and should be treated accordingly. To protect the environment, and themselves from future soil reclaiming and decontamination costs, Southern Power Co. should evaluate a change in their cleaning procedures. Portable dikes made of chemically resistant materials should be used to contain and collect the spent degreasing solvents during cleaning operations. Spent solvent can be recaptured and reclaimed using an explosionproof distillation unit. Remember, when using chemicals, there is no substitute for responsible care.

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14 . ' Petroferm Case Study 115-Page 1 Case Study #5 Spot Maintenance of Motors and Electrical Equipment Petroferm Inc. The Problems The problems associated with this case study include: 1. The wide range of sizes of parts being cleaned; 2. The amount of waste generated by spraying the cleaner from a drum; 3. The high equipment operating voltages - water-based cleaners and cleaners leaving conductive residues cannot be used; 5. The lack of mobility of the large equipment; 6. The absence of sewers and running water in the electrical shop where smaller parts are cleaned; 7. The workers' lack of awareness of the phaseout of 1,I, 1 -trichloroethane; 8. The high cost of equipment dcwntime - cleaning must be performed quickly. Proposed C 1 ea n i I:g C hem is t rjle q u i p m en t Aerosol cans containing a terpene hydrocarbon such as BIOACTO' PCA, and 55 gallon drums of a terpene hydrocarbon blend such as BIOACT 113 could replace the 1, 1,I -trichloroett?ane currently being used. Environmental and Safety Factors Both BIOACT PCA and 113 have zero ozone depletion potential, and do not contribute to global warming. None of their components appear on any of the EPA's lists of toxic or hazardous substances, or on the SARA 313 toxic chemicals I is t (40 C F R ). BIOACT PCA has a flash point of 117 F; BIOACT 113 has a flash point of 112 F. They are, therefore, defined as combustible by NFPA, and any waste generated would be subject to hazardous waste regulations (40CFR 261) upon disposal. The mist generated by spraying BIOACT 113 at high pressure from a drum would be flammable, so another method must be employed for applying the cleaner to the larger equipment. "BIOACT" is a registered trademark of Petroferm Inc.

15 Pet rof erm Case Study #S-Page 2 Summary There are several advantages in using BIOACT PCA and 113 over 1,I,Itrichloroethane. First, they do not evaporate as quickly as 1,I,I, so cleaning may be achieved with less solvent. They would have a high solvency for the soils described, and their residues are non-conductive. Because their vapors are not hazardous, they could be used in areas with poor ventilation. The slower evaporation of these solvents is also a disadvantage. Because work must be completed quickly, there is the potential for some of the material to remain following cleaning. Forced air or another method of drying may have to. be employed. Unfortunately, there is no "drop-in" replacement for 1,I,Itrichloroethane; each of the alternatives has limitations.

16 NON-PANELIST SUBMISSIONS

17 , * " CRC Industries, Inc. Case Study i/5 Case Study #5 - Spot Maintenance of Motors and Electrical Equipment CRC has a line of maintenance chemicals for the electrical and electronics industries. We offer several alternatives to 111- trichloroethane. CRC will work with users to find the best alternative for their particular application. CRCIs recommended alternatives: 1. Lectra Clean I1 - a blend of paraffinic hydrocarbon and propylene glycol ether. This product can be considered a low vapor pressure cleaner. Completely non-chlorinated. High dielectric strength of 43,000 volts. Removes tough grease, oil and other soils; evaporates completely. Available in aerosol cans, one and five gallon cans and 55-gallon drums. 2. Quick Clean - contains no Ill-trichloroethane yet is nonflammable, has excellent cleaning ability and evaporates quickly. Available in aerosol cans, one and five gallon cans and 55-gallon drums. 3. Cable Clean HF, Cable Clean RD and Cable Clean NP- three alternatives to Ill-trichloroethane. Designed specifically to clean high voltage cable but can also be used to clean any electrical equipment. IIHFfl is petroleum based with a moderate flash point; I1RDlt is an Italternatively chlorinatedg1 alternative to 111 that works just as well but is not ozone depleting; IINPtl has the latest terpene technology. 4. Contact Cleaner an HCFC-based cleaner. Nonflammable and quick evaporating. This product received a special exemption from the EPA for use on electrical and electronic equipment. 5. QD Contact Cleaner - contains no CFCs or chlorinated solvents. Evaporates quickly. Harmless to most sensitive plastics.. It is important that the user choose the right product for the application.

18 c. Ocs Systems Case Study #5 CASE STUDY #5 - Spot Maintenance of Motors & Electrical Equipment - Solution! The recommended product is O.C.S. NFH2002. NFH2002 is biodegradable, non-toxic, non-ozone depleting, non-combustible and non-ionic. It is a fully aqueous product that meets the South Coast Air Quality Management District s VOC li in i ts. The cleaning of generators and windings can be cleaned with a good aqueous product by following some guidelines and some experimenting by the user company. The O.C.S. NFH2002 is very effective in removing carbons and heavy greases without hurting windings or insulations. The method of cleaning would be done by using the O.C.S. NFH2002 at an 8:l dilution ratio in a hot (165 F) medium pressure washer or steam cleaner. The use of the hot liquid is to facilitate drying. Any residue of product left on the part is non-conductive and non-ionic. For difficult parts, heavy greases and carbons, spray, let soak for 15 minutes and spray off again. Repeat if necessary. The equipment of course could not be energized during this process. Smaller, disassembled parts can be cleaned in heated parts washers. Sometimes a solution of 20% denatured alcohol mixed with 80% D.I. water as a rinse has been used, along with a compressed air blow off to ensure drying and no conductive residue is remaining. There is also a very small portable steam cleaner available. It makes 120 PSI, with 500 F heat. This would be effective on smaller windings and motors. O.C.S. NFH2002 would be sprayed onto the soiled parts and then hit by the steam cleaner, thus getting a clean and almost instantly dry part. The waste should be captured and recycled with the use of an ultra filtration system. The yearly cost of the O.C.S. NFH2002 would be 1/5th the cost of the utility s l,l,ltric hloroethane cost. The equipment can still be cleaned in place and the smaller components can still be taken to an electrical shop. These electrical shops usually have drum mounted wash tanks there, and if not, there are a wide variety and sizes of wash tanks available. Ventilation is not a problem with the O.C.S. NFH2002 cleaner. Maintenance may take a little longer or it may be quicker. This is one of the areas that take experimentation.