SUPERCRITICAL FLUID EXTRACTION CLEANER APPLICATION

Transcription

1 - THE MASSACHUSETTS TOXICS USE REDUCTION INSTITUTE SUPERCRITICAL FLUID EXTRACTION CLEANER APPLICATION TEXAS INSTRUMENTS INCORPORATED Technical Repot No Univesity of Massachusetts Lowell

2 Supecitical Fluid Extaction (SFE) Cleane Application Texas Instuments Incopoated Raymond P. Lizotte, J. Senio Envionmental Specialist Mateials & Contols Goup Texas Instuments Incopoated Attleboo, Massachusetts The Toxics Use Reduction Institute Matching Gants Pogam Decembe 1994 The Toxics Use Reduction Institute Univesity of Massachusetts Lowell I I All ights to this epot belong to the Toxics Use Reduction Institute. The mateial may be duplicated with pemission by contacting the Institute. m m - m The Toxics Use Reduction Institute is a multi-disciplinay eseach, education, and policy cente established by the Massachusetts Toxics Use Reduction Act of The Institute sponsos and conducts eseach, oganizes education and taining pogams, and povides technical suppot to pomote the eduction in the use of toxic chemicals o the geneation of toxic chemical bypoducts in industy and commece. Futhe infomation can be obtained by witing the Toxics Use Reduction Institute, Univesity of Massachusetts Lowell, One Univesity Avenue, Lowell, Massachusetts 'Voxics Use Reduction Institute, Univesity of Massachusetts Lowell

3 Toxics Use Reduction Institute Matching Gants Pogam The Institute annually povides diect funding to Massachusetts industies on a matching basis fo toxics use eduction (TUR) feasibility and technology studies. The matching Gants Pogam was initiated in FY 93 to facilitate the development and use of innovative techniques that educe the use of toxic chemicals o the geneation of toxic bypoducts in Massachusetts businesses. Gants ae awaded on a competitive basis fo companies to conduct TUR studies at thei facilities. Recipients pepae poject epots which assist in tansfeing toxics use eduction technologies and methods to othe companies. Notice This epot has been eviewed by the Toxics Use Reduction Institute and appoved fo publication. Appoval does not signify that the contents necessaily eflect the views and - policies of the Toxics Use Reduction Institute, i.lo does the mention of tade names o commecial poducts constitute endosement o ecommendation fo use.

4 I. INTRODUCTION Supecitical Fluid Extaction (SFE) Cleane Application Raymond P. Lizotte, J Senio Envionmental Specialist' Texas Instuments Incopoated Mateials & Contols Goup 34 Foest Steet MS 1- Attleboo, MA Phone: Fax: Metal cleaning in an Industial setting is typically an envionmentally hazadous activity. Until ecently, vapo degeases utilizing halogenated solvents wee pevalent though industy. Halogenated solvents have been elatively cheap, extaodinaily vesatile and waste disposal costs have been peceived as insignificant. Today, it is eadily appaent that Industy's eliance upon halogenated solvents as metal cleanes have esulted in a myiad of envionmental, health and safety concens, esulting in egulations that has esulted in inceased costs fo companies who continue using these toxic mateials. Consequently, a geat deal of effot has been devoted to developing altenative cleaning technologies. Texas Instuments Incopoated, Mateials & Contols Goup (TI), with headquates in Attleboo, MA, has been actively pusuing altenatives to halogenated solvent vapo degeasing since Aqueous, semi-aqueous, and "no-clean" technologies have been implemented to educe solvent usage by moe than 6%. Howeve, seveal manufactuing poduction units have been unable to find a technically feasible and cost-effective altenative to vapo degeasing. In 199, TI qualified the use of supecitical cabon dioxide as a solvent capable of cleaning mineal oil esidue fom tempeatue sensitive metal pats. The conceptual design of the cleane equipment included a lage cleaning chambe capable of meeting TI'S cleaning equiements fo an entie shift. The high capital cost of such a system pevented TI fom employing supecitical fluid extaction technology in its outine cleaning opeations. In 199, TI engaged with CF TECHnologies (CF TECH) to evaluate the application of a smalle scale SFE technology to clean oganic esidues fom metal pats assembled into moto potectos. This pape documents the effots of Texas Instuments Incopoated, Mateials & Contols Goup (TI) to qualify a Supecitical Fluid Extaction (SFE) Cleane. The pape is divided into five sections: The SFE Cleaning Pocess Descibed SFE Technical Feasibility Evaluation Poposed SFE Cleane Design and Cost Financial Assessment Conclusions This poject was undetaken as pat of a Toxics Use Reduction Institute (TURI) Matching Gant Pogam fo The SFE Cleaning Pocess Descibed A. The SFE Cleaning Pocess Supecitical fluids today ae being used in a vaiety of applications as divese as the decaffination of coffee and the teatment of hazadous wastes. Fo the last seveal yeas, metal-finishing and electonics industies have been looking at SFE technology as a pomising substitute fo halogenated solvent usage in manufactuing opeations. Envionmental concens elated to the use of halogenated solvents and new egulations have motivated companies to find altenative manufactuing techniques that do not ely on these substances. SFE has eceived a geat deal of scutiny due to the envionmental acceptability of the most common SFE solvent, cabon dioxide (CO). Supecitical fluids have been used as solvents fo extacting oganic chemicals fiom mixtues in applications such as phamaceuticals, petochemicals, explosives, foods (decaeinating coffee and tea), and polymes. Also, the technology has been successfully employed in applications such as ecystallization, deposition, impegnation, and

5 suface moditication. The use of supecitical fluid extaction to "extact" oganic contamination fom metal, ceamic o composite pats ae a natual outgowth of these pevious applications. (1) Pecision suface cleaning with citical fluids uses the poweful solvent popeties of gases compessed to thei citical point. Each substance has a unique citical point, defined by the tempeatue and pessue at which the liquid and vapo phases become identical. Citical fluids have a useful combination of liquid-like density and solvency, and gas-like viscosity and difisivity. Supecitical fluids ae effective cleaning agents because of thei ability to apidly penetate substates and small intestitial spaces. Afte dissolving any contaminants, the citical fluid is easily and completely emoved because it lacks suface tension. P R TEMPERATURE SUPERCRITICAL. FLUID REGION Fig. 1. Phase Diagam fo a single component gas such as COz This cleaning pocess involves the emoval of contaminant, pincipally oganic mateials, fom the suface, holes, poes and cevices of complex pats, assemblies, instuments and electonic hadwae. Oganic mateials that ae emovable include solvent and flux esidues, lubicants, oils and-coatings. Paticulate emoval is possible and enhanced when the citical fluid solvent is used in conjunction with physical means such as agitation o ultasound. The citical fluid of choice fo suface cleaning applications is most often cabon dioxide (COz), eithe pue o in combination with a small amount of cosolvent. Solvent popeties can be adjusted by small changes in tempeatue and pessue, allowing CO to dissolve a ange of oganic compounds. The advantages of COz include a nea ambient citical tempeatue of 3 1 C and a modeate citical pessue of 11 psi. See figue 1. CO is also nontoxic, non-hazadous and non-flammable. It has no ozone-depleting potential and is easily ecycled. B. Cleaning System Opeation Typically, citicalfluid cleaning opeations ae a batch pocess. The system consists of two pimay pessue vessels, a cleaning chambe and a sepaato. Othe majo equipment includes high pessue pump(s), pessue egulato(s), pessue eduction valve(s), and inteconnect piping. Systems ae eithe manually contolled o completely automated, equiing no opeato attention duing the cleaning cycle. In the latte case a set of pe-pogammed opeating paametes, optimized fo the mateials being cleaned, contols the pocess. The pocess schematic in Figue illustates the typical cleaning opeation and seveal optional featues. Mateials to be cleaned ae loaded into the cleaning chambe using an appopiate containe o fixtue. The chambe is then sealed using a closue mechanism designed fo the opeatos and woking envionment. The cleaning pocess begins by pumping liquid COz fom a stoage vessel into the cleaning chambe and pessuizing the chambe to opeating conditions. At this point the cleaning chambe is isolated fom the est of the of the system and the mateials emain immesed in supecitical C. The cleaning pocess then poceeds by using any one o a combination of the following options: immesion only fo a specific length of time agitation of the cleaning chambe contents eciculation of the supecitical CO displacement of the CO in the cleaning chambe with additional volumes of fesh C At the end of the cleaning cycle, additional fesh CO is pumped into the cleaning chambe, displacing the contaminated CO solvent into the sepaato. As the CO exists the cleaning chambe, it passes though a pessue

6 eduction valve and vapoizes in the sepaato. Non-volatile contaminants collect in the bottom of the sepaato and C;1 vapo exits fom the top. Depending upon the scale of the opeation, ecovey and euse of the CO may be economically justified. h CQ (Gas) Expansion Valve S E Cleaning Chambe P, PSI Typical A Opeating Pessue Pats R A T R Supecitical CQ (Gas) Souce Pump Extacted Oils Lubicants, etc. CQ Reciculation Loop Pump C. SFE Cleaning System Applicability Like any cleaning technology, SFE woks bette on cetain classes of soils. SFE has been employed to successfully emove oils such as hydocabons, estes, silicones, pefluoopolyethes, halocabon substituted tiazines, etc. They ae commonly used in industial lubicants and ae the types of soils emoved by vapo degeasing and aqueous cleaning. Inoganic mateials, such as metal salts, oxides, dust and lint ae not nomally emoved by SFE. The study descibed in the Section III evaluates the applicability of SFE as a method of emoving a mineal oil and hydocabonbased stamping lubicant fi-om poduct manufactuing in TI'S Disc Manufactuing poduction unit. ~ixe / CQ Recycle Loop Manufactuing Fig.. Batch Cleaning System Flow Diagam I A. Poduction Unit 1, Disc The Disc Manufactuing poduction unit, designated Poduction Unit 1 on TI'S Toxics Use Reduction Fom R, manufactues monometal and bimetal discs (i.e., ound 'diaphagms') that change cuvatue in esponse to pessue, tempeatue o cuent. These discs ae the woking mechanism of a wide ange of pecision contol switches manufactued by TI in Poduction Unit 36, Pecision Contol Devices. The disc foming pocess is popietay and the pecise natue of the opeations is maintained as "TI Stictly Pivate." The discs ae soiled twice duing the poduction pocess: once duing the stamping of the disc fom stips of themostat mateial (fom Poduction Unit 5, Themostat Mateial Stip) and duing the calibation opeation. Cuently, a tichlooethylene vapo degease, as descibed in Table I, is used to emove these soils. Table 1 : Disc Depatment Vapo Degease Desciption Geneation (lbs) Planning Yea Baon-Blakeslee, Model Numbe Base Yea (199) 63,191 THLLV, Coss-od Vapo Degease Planning Yea (1993) 44,88 39 Planning Yea (1998) 5, 4 3. Test Pogam The tests wee pefomed in a one lite vessel outfitted with a basket that could be set to otate at vaious speeds. The C was eciculated once the vessel was chaged to supecitical conditions (condition 3). Thee expeiments wee conducted as follows:

7 Table : Expeiment Conditions Expeiment Supecitical State Rotation I 18OoF,, PSI Static (no otation) I1 18oF,, PSI High to Modeate otation III 18oF,, PSI, High puity Low otation ClFilteed Oganic esidue evaluation consisted of a suface cabon level analysis pefomed by TI'S Technical Suface Laboatoy. Yeas of expeience with the vapo degeasing of bimetal discs had allowed TI to establish an acceptable level of oganic esidue. Suface cabon level test esults ae in micogams. To compae the test to othe suface cabon level analyses, a facto is developed elating the suface aea of one tested population with anothe. C. Test Pogam Results TI povided sample pats to CF TECH to clean in thei laboatoy. Tests wee conducted at the CF TECH facility in Hyde Pak, MA and wee tanspoted to TI fo analyses in TI'S Technical Sevices Laboatoy. The following table summaizes the esults of the testing pogam. Table 3: Suface Cabon Levels (micogams) Test No. Expeiment I Expeiment IT Expeiment III Sigma Mean Testing significance was analyzed using an "F" test (degees of feedom = 4, citical value = 16., confidence = 99%) that shows a significant diffeence exists between expeiments 3 and 1. Although these two expeiments wee testing two vaiables, it is likely that the use of high puity cabon dioxide and Millipoe filteing contibuted to the vaiance. Thee was little significant diffeence between expeiments 1 and o between expeiments and 3, although a testing population of 5 pieces may not have been sufficient to test fo the effects of agitation on cleaning. D: Compaisons with Appopiate Cleaning Technologies Oveall, the test esults demonstated that SFE Cleaning was compaable with othe cleaning technologies. The following table compaes the SFE Cleaning expeiment uns with simila tests pefomed using othe cleaning technologies such as Conventional Vapo Degeases (New unit, Old -- Modified 197 unit) and Aqueous Washing. Table 4: Compaisons with Appopiate Cleaning Technologies: Suface Cabon Levels (micogams) Old Vapo New Vapo Aqueous SFE Degease Degease Washing Exp. I Exp. It EH~. Aveage 4." 1.* 15." SCL * Cleaning Study, Febuay 1, 1989, Moveable Contact/Disc of 5HM Moto Potecto extapolated to match existing testing. Although futhe testing will be necessay to fully qualify SFE Cleaning, it was detemined that the technical feasibility study had sufficiently demonstated the applicability of the technology and the following conceptual piece of cleaning equipment was designed. m

8 E: SFE Cleaning System Design CF TECH has been investigating the use of SFE cleaning as a method of cleaning pecision pats, defluxing cicuit boads, and emoving confomal coatings. In addition to the poject to detemine the applicability of SFE to clean hi-eliability themostats, CF TECH has been woking with TI to poduce an economically feasible SFE cleaning system fo the lage-scale degeasing of bimetal discs. Fom the wok in the hi-eliability themostats aea, CF TECH had indicated that an SFE cleaning system with multiple vessels attached to a cental chaging system would esult in a system that was moe likely to both meet thoughput equiements and be financially justified. Figue 3 povides a schematic dawing of this multi-vessel SFE Cleaning System. Disc Manufactuing poduction unit thoughput equiements ae descibed in the following table:. Table 5: Disc Manufactuhg ~oduction UnitPoduction Data Aveage Lot Weight Maximum Lot Weight LotsIDay* (lbs) (lbs) LotsIH * 16 hous pe day, 6 days pe week fo a total of 4,99 hous pe yea of opeation A single vessel SFE Cleaning System can be optimized to clean thee maximum weight lots evey 3 minutes. Consequently, a thee vessel system is capable of cleaning 18 maximum weight lots evey hou. Since the aveage weight of a lot is less than 15 lbs, a thee vessel SFE Cleaning System is adequate to meet the anticipated 19 lots pe hou fom the Disc Manufactuing opeation with sufficient capacity in eseve fo potential futue gowth. Cop Recycle Loop Extacted Oils While thee is si@cant uncetainty egading the cost of the cleaning system descibed above, the cuent level of infomation povides sdiicient infomation to poduce an a ough estimate fo use in the financial assessment. TI appoached CF TECH, a competito of CF TECH and a pessue vessel manufactue to povide cost estimate details. In addition to the cost of constucting the cleaning equipment, costs elated to mateial handling, engineeing, and installation was included. It was estimated that the capital expenditue fo the SFE cleaning System would total $35,.. IV FINANCIAL ASSESSMENT The SFE Cleane Poject was detemined to be a Capital Expenditue. TI has an established pogam unde which poject manages equest funding. TI'S Capital Budgeting pocess consists of: Geneating the Idedneed by the Poject Manage Pefoming the Financial Assessment Obtaining Management Appoval Executing the Poject Closing the Poject

9 In ode fo the Capital Budgeting pocess to esult in consistent decisions, Financial Assessments must conside all cash flows thoughout the poject's lifetime, the time value of money, account fo the cost of obtaining capital, and facto isk. The financial assessment consisted of the following six steps: Gatheing Relevant Cost Infomation Concening the Existing Poduction Unit Estimating Relevant Cost Infomation fo the Poposed Poject Listing Diffeential Costs Between Existing and Poposed Geneating the Cash Flow Evaluating Intangible Factos Intepeting the Results The fist two steps wee done in detail and have not been povided as pat of this pape. TI applies a cost accounting system that attempts to compehend total costs and allocate those costs within the opeating aea that causes them to be geneated. Costs that ae often consideed "ovehead" ae-allocated back to the cost cente eithe diectly o via an allocation fomula based upon an activity measuement. Although this accounting methodology falls shot of activity based costing, it povides sufficiently detailed infomation to assess a poject such as this. The financial assessment is pefomed by the Poject Manage of the manufactuing aea diectly esponsible fo geneating the concept and savingslexpenses ae diectly accued by that manufactuing aea. Consequently, incentives to compehend full envionmental costs and the savings to be gained though pollution pevention exist within those TIes esponsible fo developing pollution pevention options. To pefom the financial assessment, the oiginato of the Cash Flow must make a numbe of assumptions. Fist, opeating costs (utilities, labo, etc. pe unit of thoughput) and some indiect costs (employee taining, insuance, epai & maintenance, etc.) wee assumed to be equivalent between existing and poposed Poduction Units. In addition, liability costs caused by potential penalties, fines, pesonal injuy, coective actions elated to the existing and poposed Poduction Units wee not assessed as pat of this study. Tables 6 and 7 descibe the diffeential savings and expenses associated with implementing the SFE Cleaning System. The Annual Savings (Tichloethylene Puchase & Disposal, Regulatoy Fees, and Miscellaneous Costs) ae compiled in the SAVINGS line of the SFE Cleane Cash Flow. The Clean Ai Act/MACT fo Degeasing Cost is located in the OTHER SAVINGS line. Unde Title 111 of the Clean Ai Act Amendments of 199, the U.S. EPA will be establishing emission standads that eflect the Maximum Achievable Contol Technology (MACT) fo halogenated solvent degeasing. The cost descibed in this line eflects an estimate fo upgading the existing equipment to meet the emission standad. The TI Facilities Oganization has povided a quotation fo weck-out and disposal of the existing degeasing equipment. Since the Disc Manufactuing Poduction Unit will be shutdown to accommodate installation, the START-UP EXPENSES includes the cost fo lost poduction. The CAPITAL EXPENDITURE has been split into two payments, 3% of the $35K upon placement of the Puchase Ode with the emainde upon delivey of the equipment. It is estimated that the design-and-build schedule will esult in delivey of the SFE Cleane within 4 weeks of placing the ode. Table 6: Desciption of Savings Saving ($Q Desciption 19 Annual Puchase of Tichlooethylene (Note: Incease at 5%/y.) 4 Annual Disposal of Tichlooethyleneloil wastes (Note: Incease at 8%ly.) 1 Annual Toxics Use Reduction Feepogam Administation (Note: Flat each yea) Annual Clean Ai Act Feepogam Administation (Note: Flat each yea) Annual Miscellaneous Envionmental, Safety & Health Cost (Note: Incease at 5%/y.) 1 Clean Ai Act/MACT fo Degeasing Cost (Note: One time chage in 1998) Table 7: Desciption of Expenses Expenses ($K) Desciption - Stat-up Expensemeck-out and Disposal of Existing Degease (Note: One time chage in 1996) -115 Fist Yea Capital Expenditue (3% of $35K Capital Costs upon placing ode) -35 Second Yea Capital Expenditue (Remainde of $35K Capital Costs upon delivey)

10 To assess the financial impact of a pollution pevention poject such as the poposed SFE Cleane, listing the costs and savings is not sufficient. The assessment needs to include, not only the cuent costs, but futue conditions. The capital budgeting pocess utilized by industy to jusw investment decisions incopoates the impact of the capital poject to the fim's cash flow ove time. As indicated unde Desciption in Table 6, the savings change ove time as factos change the value of the savings. The estimation of costs and savings ove a ten yea hoizon is complicated and uncetain. Without explicit data to base futue costs and savings, TI extapolates these values based upon the tends of the past 5 yeas. The SFE Cleane is maintained as a 5-yea asset in accodance with TI accounting pocedues. The depeciation is applied to the Cash Flow as a 15% Double Declining Balance. The depeciation is compehended on the DEPRECIATION line of the Cash Flow. The SFE Cleane Cash Flow has been attached.- The economiclifetime of the equipment fo this example is 1 yeas. TI usually evaluates equipment ove 5 yeas even though the expected physical lifetime of the equipment may be longe. The CORP EXPENSE line adjusts the Cash Flow to account fo the pecentage of pofit that goes to maintaining the copoation. The AFTER-TAX SAVINGS line eflects the expected ate at which TI is taxed both at a fedeal and state level. The Discount Facto selected fo this example is The copoation sets this value based upon the cost to TI of obtaining capital. When making pollution pevention decisions, long-tem financial indications such as Net Pesent Value (NPV) and Intenal Rate of Retun (IRR) ae calculated. The Pofitability Index (PI) is calculated to allow easy compaison to othe pojects. The moe commonly used Payback Yeas is also included. Table 8 povides a summay of these esults fom the SFE Cleane Cash Flow. Table 8: Financial Indicatos Financial Indicato Value fom SFE Cleane Cash Flow (11195) Net Pesent Value (NPV) -94 Intenal Rate of ~etun(lrrj Pofitability Index (PI) Payback Yeas The Net Pesent Value (NPV) epesents the diffeence between the pesent value of the cash inflows and the initial investment amount. The NPV povides an objective, undistoted view of the futue etuns of the poject. In geneal, the ule is that the NPV must be geate than fo the poject to be accepted. The SFE Cleane Cash Flow NPV of -94, dollas is sufficient to eject the poject. The Intenal Rate of calculatesthe ate of etun that equates the pesent value of the cash flows with the amount of the investment. The SFE Cleane IRR of 1.4% is less than TI'S desied ate of etun o "hudle ate" and is sufficient to eject the poject. Included is the Pofitability Index (PI), an index that can be used to compae the SFE Cleane poposal with othe potential pollution pevention pojects. A PI of -.7 does not stack up well against othe options that ae being assessed within the Moto Contols Disc Manufactuing poduction unit. The Payback Yeas is an undiscounted (i.e., it does not account fo the time value of money) value that descibes the numbe of yeas the initial investment will be tied up in the poject. As such, it is only a quick appaisal of the meits of the poject. The 1 yea payback is longe than TI usually accepts and may be longe than the economic lifetime of the asset. The conclusion of the quantitative potion of the financial assessment is that the SFE Cleane poject does not display a positive effect on TI'S pofitability. Since the above quantitative financial assessment does not include the isks andlo intangible factos, nonmonetay concens need to be addessed. The following intangibles wee factoed into the assessment: The liability associated with the continued use of tichlooethylene in the existing poduction unit is consideed high. In 1984, TI management established as an objective the phase-out of the use of

11 tichlooethylene; consequently, they favo pojects that esult in the elimination of tichlooethylene. IMPACT -- High $ Costs. SFE Cleaning of metal pats has not been fully demonstated. Although this study included a peliminay technical feasibility evaluation, the technology has not undegone the level of evaluation necessay to be qualified as a substitute. The cost of conducting the qualification tests is likely to be modeately costly. IMPACT -- Modeate $ Costs. Highly pessuized equipment is not a "familia" technology. Unlike vacuum equipment, which has many yeas of poven use within the metal finishing industy, thee is not equivalent expeience within TI in the use of the highly pessuized equipment. Employees expessed concen that the maintenance, opeation, etc. of the cleaning vessels of the SFE Cleane may pesent a poblem. IMPACT -- Low $ Costs. In addition to the SFE Cleane, TI is evaluating othe pollution pevention options including "eliminating the need to clean." Inheently, this stategy pomises a lage payoff fo TI; consequently; moe esouces ae being dedicated to this effot. IMPACT -- High $ Savings. In summay, the intangible factos continue to justify TI'S effots to phase out the use of tichlooethylene, but not though input substitution utilizing cuent SFE cleane technology. The pupose of this study was to detemine if an SFE cleaning system was a viable substitute to the tichlooethylene vapo degease in the Disc manufactuing aea, Poduction Unit 1. Results of the technical feasibility study demonstated that the technology was wokable, but was insufficient to appove the cleane as a qualified substitute that would be acceptable to TI'S custome base. A positive esult on a custome appoved qualification investigation is necessay befoe an SFE cleaning system could be appoved to eplace the tichlooethylene degease in the Moto Contols Disc Mfg. aea. The study did povide enough infomation to design a conceptual SFE cleane. Using this design, a Capital Expenditue equest, including a financial assessment, was developed. The measues of pofitability (NPV, IRR and Payback) all lead to a detemination that SFE cleaning is not, at pesent, an economically justified technology within the Disc manufactuing aea. The conclusion of the pape is that SFE Cleaning technology is an elegant cleaning method with many envionmental benefits, but one that is not pesently cost effective. The findings of this poject have esulted in TI no longe pusuing SFE Cleaning as a Toxics Use Reduction option. R.P.L. thanks the pesonnel who assisted in this poject, especially Tom Robets, Manufactuing Enginee of the Disc Mfg. Aea, Walt Rehon and Dave Cap, Financial Analysts fo the Moto Contols Depatment, Bill McGoven and David Webe, of CF TECHnologies and John Amaal of Envionmental Consulting Sevices. P. Gallaghe and V Kukonis, "Pecision Pats Cleaning with Supecitical Cabon Dioxide," unpublished. R. Liiotte, "Supecitical Fluid Extaction (SFE) Cleane Evaluation in Fabication/Clean/Assemble Pocess Flow Opeations," Toxics Use Reduction Matching Gants Application, 199. H. Giffin, "Supecitical Fluids," unpublished. "CF Systems Copoation (Solvent Extaction)," The Supefind Innovative Technology Evaluation Pogam: Technology Pofiles, Fifth Edition, EPA/54/R-9177, 199, pp RLizotte and D.Webe, "Supecitical Fluid Extaction (SFE) Cleane Application," Confeence Poceedii fo the 1st Annual Intenational Symposium on Electonics and the Envionment, 93CH39-4, May Constubble, Monoe, Hill and Flanagan, "MACT fo Degeasing Suppot" Reseach Tiangle Institute, EPA Contact 68-Dl-1 18, W.A. 59, July Rehon, Walte, "Moto Contols Capital Budget Taining," unpublished Costing and Financial Analysis of Pollution Pevention Pojects: A Taining Packet, Notheast Waste Management Officials' Association and The Massachusetts Office of Technical Assistance, 199. "Total Cost Assessment: Acceleating Industial Pollution Pevention though Innovative Poject Financial Analysis," EPA 741IR-9/R, May 199.

12 $ e o o m NO oo O q~ ' O Ga q 3 ~ 8. u I w 9 o 8 N O d O $ z 8 i 3 i3 7 c o b N 8 N O d O O b b ; q m N N m M N Q)O m a3 m Z? O a 3 3 b b 5 N O b O O O h a 3 C Q ~ CQ O ~ ~ m m N t N F o (v 8 b UI - FJ C 9 V ) C O? y q G w b n y X o o el o - LO m UI m o m $3 h l m C * ) ~ ~ B - ~ O N I Q) Q) m NO bo m UI V) $3 b V ) m q Y G w a 3 ~ ~ * I C O O O d O b O b O d W b Q ) ~ Q) Q) mg Y F LO * m b z $ h Q) Q) a3 oo? C Q V ) b C ) C Q?,, o o d 3 $3 Q o C Q O c o O C Q o O O d o m N m g Q ) d N $3 ' Q) Q) lj$ PL II CI Q L - $ 3 S 8 ~ ~ o O O O O O o d a 3 o u E a U) s U) m E Y- d O s * L LL F I CI 3 z