TECHNICAL ASSISTANCE FOR WASTE M I N I M I Z A T I O N

B r ian A. West fa l l P o l l u t i o n Prevent ion Research Branch U.S. Environmental P ro tec t i on Agency

26 West Mar t i n Luther King D r i v e C inc inna t i , Ohio 45268

and

F. Wi l l i am K i r sch and Gwen P. Looby I n d u s t r i a l Technology and Energy Management

U n i v e r s i t y City Science Center 3624 Market S t ree t

P h i l adel ph i a, Pennsylvania 19104

I n t r o d u c t i o n

Waste min imiza t ion and p o l l u t i o n prevent ion are becoming f a m i l i a r terms t o today’s business leader . Successful a p p l i c a t i o n o f waste min imiza t ion p r i n c i p l e s i s p rov ing t h a t p r o f i t a b i l i t y can be enhanced as waste generat ion i s reduced o r e l iminated. Waste t reatment and d isposal can be expensive i f done p roper l y and very expensive i f done improper ly. Avoid ing t h e cu r ren t cos ts and f u t u r e l i a b i l i t i e s o f waste management sounds great , bu t how does the small business g e t s t a r t e d i n t h e r i g h t d i r e c t i o n ? How does t h e company which has a l ready implemented t h e obvious measures move f u r t h e r along? The USEPA promotes t h e use o f p e r i o d i c waste min imiza t ion oppor tun i t y assessments t o he lp i n i t i a t e and cont inue a permanent, e f f e c t i v e waste min imiza t ion program. Several mechanisms have been developed by t h e Federal and s t a t e governments t o a s s i s t businesses i n t e r e s t e d i n adopt ing waste min imiza t ion as a pr imary waste management s t ra tegy . One such mechanism i s t h e Waste M in im iza t i on Assessment Center (WMAC) p i l o t p r o j e c t performed by the U n i v e r s i t y City Science Center and funded by t h e USEPA.

P r o j e c t DeSCriDtiOn

The USEPA has produced and publ ished t h e Waste Min imiza t ion O m o r t u n i t v Assessment Manual (EPA/625/7-88/003, July 1988) which descr ibes a gener ic procedure f o r conduct ing a waste min imiza t ion assessment a t an i n d u s t r i a l f a c i l i t y . The d i r e c t use o f t h i s manual a t a small business l a c k i n g in-house resources o r e x p e r t i s e may be imprac t i ca l . A p i l o t p r o j e c t p r o v i d i n g waste m in im iza t i on assessments t o q u a l i f y i n g businesses a t no out -of -pocket expense was i n i t i a t e d a t t h e U n i v e r s i t y City Science Center i n Ph i lade lph ia , Pennsylvania. Two WMACs were es tab l i shed i n t h e f i r s t year o f t h e p r o j e c t - one a t t h e U n i v e r s i t y o f Tennessee i n Knoxv i l le , and one a t Colorado Sta te U n i v e r s i t y i n F o r t C o l l i n s . A t h i r d center a t t h e U n i v e r s i t y o f L o u i s v i l l e (Kentucky) was added l a t e r . The WMACs send teams composed o f f a c u l t y and s tudent members t o businesses f u l f i l l i n g a t l e a s t two o f t h e f o l l o w i n g c r i t e r i a :

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1. Gross annual sales of not more than $50 million. 2. 3.

No more than 500 employees. Lack of in-house expertise in waste minimization.

The WMAC team schedules a series of visits to each facility and provides each client a site-specific confidential report summarizing their findings and recommendations, including projected implementation costs, cost savings and simple payback times.

Implementation of the waste minimization recommendations is the responsibility of the client manufacturer. No USEPA funding is currently available nor foreseen for implementing recommendations under this project. Each facility is visited within one year to obtain actual cost and savings information on implemented recommendations. In addition, the factors determining whether or not a particular recommendation was implemented are discussed with the client. During the first year of the project, 12 assessments were completed. The implementation rate for the 87 recommendations was 52%, and 49% of the overall potential dollar savings are being attained.

Case Studies

Facility A is a manufacturer of compressed air equipment components. The manufacture of compressed air equipment components begins with the fabrication of zinc and aluminum diecast parts. Zinc and aluminum alloy ingots are melted in separate furnaces and the molten metals are then transported to diecasting machines. The diecasting machines force the liquid metals into a mold-and-plunger assembly by hydraulic compression. A water- based lubricant is sprayed on the molds, and an oil-based lubricant is used for the plunger. Excess lubricants collect in a sump and are mixed with other oil wastes for disposal. Small amounts of solvent used to clean the diecasting machines are also mixed with the oil wastes. An ethylene glycol/water-based hydraulic fluid provides the required hydraulic compression. Extensive leakage in the hydraulic fluid reservoir requires that fresh hydraulic fluid be added to maintain the proper fluid level. Used fluid is mixed with the miscellaneous oil and solvent wastes for disposal. Solid wastes in the diecasting area consist of scrap and excess metal, which is remelted in the proper furnace along with the raw metal ingots.

Diecast metal parts are transported to the machining area to be milled, drilled, and tapped as required. Most of the machining equipment uses a water-based cutting/cooling fluid. A centrifuge removes metal contaminants so that the fluid may be reused. Solids and sludge that remain are mixed with oil and solvent wastes for disposal. Some of the machining equipment uses an oil-based lubricant; no liquid wastes are generated from these machines because the oil is recycled. Occasionally, lubricants are added to compensate for lubricant that remains on the metal parts. Small amounts of solvent used to clean the machines are mixed with the oil wastes. Oil-contaminated metal shavings from the machining area are sold to an outside firm for reuse.

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After machining, parts are washed with an alkaline solution containing borax to remove remaining cutting oil and are deburred before application of protective coatings. Oil is collected by a skimmer in the alkaline washer and mixed with the water-based lubricant from the machining area. Effluent from the washer is combined with other aqueous wastes that flow to an on-site wastewater treatment unit.

Steel parts that have been manufactured at an off-site facility are cleaned i n a small vapor degreasing unit with l,l,l-trichloroethane. Waste solvent and still bottoms from the vapor degreaser are drummed and disposed of as hazardous waste.

Chromate conversion, phosphate, or anodized coatings are applied by immersing the parts in a series of chemical baths and rinses. The chromate conversion coating line is automated, and the phosphate and anodized coating lines are operated manually. The actual treatment process varies for each metal coated. Effluents from the coating lines and alkaline washer are combined and treated in the wastewater treatment facility. Sodium metabisulfite is added to reduce hexavalent chromium to trivalent chromium. Sodium hydroxide is then added to raise the pH from about 2.75 to 8.5 and to form insoluble metal hydroxides. Adding calcium chloride removes sulfate and phosphate ions as insoluble calcium compounds. Precipitates are flocculated with a polymer and allowed to settle to form a metal hydroxide sludge, which is periodically pumped to a filter press for dewatering and shipped to a hazardous waste disposal facility. The supernatant's contaminant level is below the pretreatment specifications of the local POTW, so it is discharged to the sewer system.

Powder coating is applied to some of the metal parts, which are then cured i n a furnace. No hazardous waste is generated in the powder coating process. Plastic injection molding machines, which use an oil-based hydraulic fluid, produce the plastic components of the compressed air equipment. The hydraulic fluid is filtered periodically and reused. Contaminated fluid is mixed with other oil and solvent wastes for disposal.

Hazardous wastes are also generated in processes not directly related to manufacturing. The tooling area, where molds and equipment are maintained, contains equipment that employs the same water-based cutting/coolant fluid used for machining. This fluid is also reused after processing with the centrifuge. The clean room generates about 10 gal/mo of waste chlorofluorocarbons from cleaning components to be used for medical and other special applications; the waste is sent off-site for disposal. Small amounts of solvent-based paints are used for machinery, and any waste is sent off- site for disposal.

Before the WMAC's team assessment, the plant had already taken the following steps to minimize and manage its generation of hazardous wastes:

Using a centrifuge to remove metal chips and fine particles from the water-based coolant/cutting fluid used in the machining area. The

Surface coatings are applied to all metal parts.

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clean fluid is then collected and reused.

The plant plans to eliminate on-site treatment of steel parts; this will reduce or eliminate the need for solvent degreasing and also the need to dispose of contaminated l,l,l-trichloroethane.

Using an alkaline wash to remove oil from metal parts before surface treatment. This alkaline wash replaced more traditional cleaners, such as halogenated organic compounds.

Using a filter press to reduce the water content of the hazardous metal hydroxide sludge before shipment off-site for disposal.

. Using powder coatings on metal parts. Replacing solvent-based paints with powder coatings eliminated solvent-based paint wastes and reduced the emission of volatile organic compounds.

Collecting metallic wastes from the diecasting process and remelting them in the appropriate furnace. Oil-contaminated metal chips from the machining area are collected and sold to a metal recycler.

- Minimizing the use of solvent-based paints for general painting. Solvent-based paints are only used on machinery and other items not suited for water-based paints.

Table 1 summarizes the principal sources of waste, the amounts generated, and the associated management costs. Table 2 briefly describes current plant practices, the recommended waste minimization opportunities, and savings and cost data.

The WMAC also investigated several other opportunities for waste minimization that require relatively lengthy paybacks or are considered to be beyond the scope of this program. These measures are:

Implementing a preventative maintenance program for the diecasting machinery to reduce the frequency and cost of unscheduled repairs.

Establishing a program to segregate oil wastes to allow recycling of waste oils.

Using a water/glycol fluid instead of a petroleum-based fluid as the hydraulic fluid in the plastic injection molders. The water/glycol fluid would reduce waste generation because of its longer lifetime.

Installing a solvent recovery unit to remove contaminants from the l,l,l-trichloroethane used in the vapor degreasing unit.

- Using deionized water in the reagent baths in the chromate conversion coating line.

Removing waste oil from the wash water from the alkaline cleaner.

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Table 1. Summary of Current Waste Generation

Waste stream Waste generated Annual quantity Annual waste generated, gal management cost

Die casting

Plastic molding

Machining of die cast parts

Vapor degreaser unit

Treatment o f rinse water from the coating operation and the a1 kal ine washer

Cleaning of parts used in special applications

Painting of plant equipment

Combined wastes including water-based 9,660 $ 5,300 die lubricant, oil-based plunger 1 ubricant, water-soluble cutting/cool ing fluid, water/glycol hydraulic fluid, and equipment cleaning solvents.

Combined wastes including petroleum- 1,780 based cutting/cool ing fluid, water-sol ubl e cutting coolant, water/glycol hydraulic fluid, and equipment cleaning solvents.

Combined wastes including petroleum- 18,060 based and water-based cutting/cool ing fluids and equipment cleaning solvents.

980

9,920

1, 1,l-trichloroethane and still bottoms.

350 1,750

Rinse water laden with heavy metals and reagents used in chromate conversion coating , phosphating , and anodizing .

2,930,000 4,900

Waste chlorofluorocarbons. 100 130

Waste solvent-based paint and thinner. 400 2,560

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Table 2. Summary o f Recommended Waste Min imiza t ion Oppor tun i t ies

Present p r a c t i c e Proposed a c t i o n Cost savings

Reagents used t o c rea te a conversion coa t ing on aluminum p a r t s conta in chromium and the re fo re generate hazardous waste. These reagents contaminate r i n s e water and c o n t r i b u t e t o t h e amount o f hazardous s o l i d waste t h a t i s generated.

O i l wastes f rom t h e d i e cast ing, i n j e c t i o n molding, and machining areas are combined and form a mul t iphase f l u i d t h a t i s sent t o a disposal f a c i l i t y .

Drainage t ime over reagent baths i n t h e chromate conversion coa t ing l i n e i s 5 sec.

Rep1 ace the chromium-containing S o l i d waste reduc t ion = 1280 ga l / y r reagents w i t h reagents t h a t L i q u i d waste reduc t i on = 659,300 ga l /y r generate no hazardous waste. The Cost savings = f5,480/yr proposed coat ing process does Implementation cos t = $0 n o t r e q u i r e r i n s i n g a f t e r coa t ing Payback i s immediate. and the re fo re w i l l n o t contaminate r i n s e waters.

Use magnesium c h l o r i d e as a de- emu ls i f y ing agent t o break t h e o i l - w a t e r emulsion. The o i l waste can be c o l l e c t e d i n a tank and sent t o an o i l recyc le r . The aqueous phase can be t rea ted a t t h e p lan t ' s wastewater t reatment f a c i 1 i t y .

Waste reduc t ion = 16,230 g a l / y r Cost savings = S6,820/yr Implementation cos t = $2,500 Payback = 0.4 years

Increase t h e drainage t ime t o 10 sec t o a l l ow more reagent t o d r a i n back i n t o t h e bath. Waste reduc t ion w i l l Implementation cos t = $0 r e s u l t from extended l i f e t i m e s f o r t h e baths.

..aste reduc t ion = 17 ga Cost savings = $210/yr

Payback i s immediate.

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Facility B is a printed circuit board manufacturer. Laminated flat sheets of nonconducting material are first cut to a size slightly larger than the desired end product, then drilled by programed high-speed drills, and finally deburred at the holes and board edges by rotating brushes. A thin layer of copper is deposited by electroless plating on boards that are first cleaned and rinsed and then coated with a catalyst for the reduction of the copper. To apply the circuit patterns, a dry film process is used--laminating a photosensitive polymer resist, covering parts of the board with the printed circuit design mask before exposure to ultraviolet light, developing with sodium carbonate, and eventually rinsing with tap water.

the preceding series of operations. copper to protect the circuit design from the alkaline etchant used to strip away the plating resist. Any copper not protected by tin is also etched away by an a1 kaline solution. solution removes the tin to complete the electronic circuitry on the board, which is then water-rinsed and air-dried. apply solder to the desired areas, which are the portions of the boards not coated by an epoxy solder mask, which also functions as an insulator. Then a eutectic solder is coated on the areas not covered by the mask. To meet certain customers' specifications, connectors are sometimes gold plated before solder mask application.

Actions already taken by this plant to reduce hazardous wastes include:

Using dry film photoresist to eliminate chlorinated solvents associated with silk screen application.

Substituting tin for lead solder after electrolytic copper plating (though a small amount o f tin/lead solder is required as a final coating).

Combining an automated electroless plating machine with countercurrent rinsing to cut down drag-out of plating solution and to reduce the quantity o f rinse water.

Agitating these rinse tanks with compressed air to get better rinsing in a given tank volume.

Using deionized water in the electrolytic plating lines to lessen the formation of sludge (hard-water deposits).

Converting to plastic covered racks for those same electrolytic plating lines to reduce (by 75%) the amount of stripping solution needed to remove excess copper and tin deposits on the racks.

Applying mechanical deburrers, scrubbers, and hot-air dryers to eliminate some hazardous solvents. are collected and sold to a metal reclaimer.)

Electrolytic plating of copper occurs on the circuit design developed in Then tin is electrolytically plated on the

Finally, an ammonium bifluoride/hydrogen peroxide

The principal remaining step is to

(The dusts from these operations

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Most of the hazardous waste generated in this plant occurs in various liquid streams. scrubbing, plating, and etching. Dissolved cooper occurs in the rinses following etching and plating, in the accelerator and acid activator baths on both plating lines, and in the alkaline etch and rack stripping solutions. Metallic copper is generated by mechanical cleaning operations, drilling and routing operations, and cutting operations. and stripping; lead, from rinsing and deburring.

hazardous are those from the dry film developer, the post-clean rinse, the gold plating rinse, and the spent resist stripper. The other rinses and dumps are directed into a large trench with a level controller which activates a pump to transport the liquids to a treatment system that utilizes chemical reactions, precipitation, and membrane filtration. concentration tank are removed by bleeding a "slip stream" to a settling tank, from which sludge is dewatered to about 60% solids before it is hauled to a disposal site for hazardous wastes. streams and associated waste management costs.

Eight waste minimization opportunities are summarized in Table 4, together with the projected reductions in emissions and the associated savings and costs. The savings are calculated for each recommendation independently, but some are related such that the results from implementing one can affect the results calculated for another independently. It should also be noted that cost savings can often be achieved through operations such as filtration, precipitation, flow reduction, and concentration of solutions and suspensions. These, along with deionization and reagent substitution, are readily available and can be highly effective tools in efforts to reduce waste emissions and to lower costs.

The main sources of metallic contamination are the rinses after

Tin comes from electrolytic plating

Rinse streams discharged to the sewer because they are not considered

Suspended solids in an associated

Table 3 is a summary of the major waste

Conclusions

Waste minimization opportunity assessments are valuable components of on- going waste minimization programs. are very effective, but may be impractical for small businesses lacking in- house expertise. A positive experience with a technical assistance team can provide immediate opportunies for cost-effective waste minimization activites, usually resulting in a commitment to waste minimization as the primary waste management strategy.

The assessment procedures in EPA's Manual

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Table 3. Summary o f Current Waste Generation

A. HAZARDOUS LIQUID WASTES

Waste stream Waste generated

Annual q u a n t i t y generated (ga l lons) T r

Annual waste management

cos t n t Disposal Recycl

E l e c t r o l e s s copper:

Waste r i n s e s Copper p l a t i n g and drag-out 916,663 C a t a l y s t p red ip Table sa l t /water dumps 530 Acce le ra to r Copper-laden, d i 1 Ute

hyd roch lo r i c a c i d 530 $10,488 S 587

E l e c t r o l y t i c copper:

Ac id soap preclean Ac id soap dumps 10,189 Water r i n s e s

p l a t i n g drag-out 366,665 Copper p l a t i n g pred ip 10% s u l f u r i c a c i d dumps 3,266 Tin p l a t i n g pred ip 2% s u l f u r i c a c i d dumps 3,266

Soap, etch, copper & t i n

S 4,380 S 246

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(continued)

Table 3. (continued)

Waste stream Waste generated

Annual Annual waste quantity management

(gallons) Treatment Disposal Recycling generated cost

Resist strip, copper etch, and tin strip:

Water rinses

A1 kal ine etch Tin strip

Rack stripper

Other processes:

Deburrer #1 Deburrer #2

Scrubber

Hot air leveling

Etch, resist and tin strips

Spent ammonium hydroxide Spent ammonium bifluoride/

Spent rack stripper

drag-out

peroxide

Copper-laden rinse water Copper-, tin/lead-, and gold-laden rinse water Epoxy-, tin/lead-laden rinse water

Copper-, ferric chloride-, and hydrochloric acid- laden rinse water

549,997 13,950

1,450 1,550

S 6,285 S 352 $45,765

(continued)

366,665

366,665

183,332

183,332 $12,570 S 704

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Table 3. (continued)

B. HAZARDOUS SOLID WASTE

Waste stream Waste generated

Annual quantity Annual waste generated management (pounds) cost

Wastewater treatment system

Electroless copper:

Microetch Drilling and routing Deburrer #1 Shearing

Filters:

Electrolytic copper Post clean Auto tab plater

Metal hydroxide sludge 27,700 $5,471

Copper sulfate crystals 2,800 Copper, aluminum, and gold dust 200 Metallic copper 200 Copper/epoxy 1 aminate dropoffs 1,200

Nonhazardous filter cake 25 Tin/lead-1 aden filters 25 Gold-laden resin filter cartridges 25

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0 m Table 4. Summary of Recommended Waste Minimization Opportunities

Present practice Proposed action Cost savings

Effluent from the wastewater treatment system is sewered.

The scrubber uses 183,300 gal/yr to rinse particulates from circuit boards. The liquid con- taining particulates goes to the wastewater treatment system.

Thorough rinsing is manadatory for many operations in this plant. Observation of the plant revealed high water flow rates.

The particular brand of dry film developer in use adheres so strongly to the unexposed film that an aggressive acid soap is required for removal. This soap presents problems in the wastewater treatment unit and requires conditioning agents.

Reuse the treatment system effluent to reduce demand for rinse water. To widen the range of possible uses, some further treatment (e.g., ion exchange, adsorption, filtration) may be needed. Additional storage tanks, pumps, and piping will be required. Saving occurs in lower water demand and sewer charges.

Filter (in a closed loop system) scrubber liquids to remove hazardous particulates and recycle the water for rinsing the scrubber. Dispose of filter cartridge as solid hazardous waste.

Install flow reducers or flow meters on the water supply to seven identified manufacturing operations . Waste reduction and cost savings are calculated only for reduced water, treatment, and sewer usage.

Change to another dry film developer, use a less aggressive soap (a1 so nonhazardous), and discharge the liquid to the sewer after pH adjustment.

(continued)

Waste reduction = 1,833,325 gal/yr Cost savings = $3,84O/yr (net) Implementation cost = $22,000 Simple payback = 5.7 yr

Waste reduction = 183,300 gal/yr Cost savings = $2,15O/yr (net) Implementation cost = $650 Simple payback = 4 mo

Waste reduction = 440,000 gal/yr Cost savings = S5,840/yr Implementation cost = $360 Simple payback = less than 1 mo

Waste reduction = 13,500 gal/yr Cost savings = $23,55O/yr

Implementation cost = 0 Simple payback = immediate

(based on conditioner use alone)

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Table 4. (continued)

Tin is stripped away from the electrolytically deposited copper sites that it protects. A solution of ammonium bifluoride and hydrogen peroxide is the stripping agent. The relatively large quantity of washes is sent off-site for treatment and recovery of tin.

Deionized water is used for rinsing on the electrolytic copper and tin plating lines. Its use should be extended to the electroless copper plating line.

Solid copper waste is collected from the deburrer and copper sulfate from the microetch solution.

Plant operators hold drip racks over certain baths to reduce the quantities of drag-out. Times and drainage vary widely.

Concentrate the tin stripping solution to reduce hauling and treatment costs. Partial freezing will cost less than evaporation. The metal reclaimer has said the concentrate is acceptable, and there will be no increase in unit costs o f hauling and recycling. The separated solid can be melted and sewered.

Use deionized water in five baths in the electroless copper plating line, thereby reducing sludge formation and extending the lifetime of the bath. The savings will be achieved in lower cost o f treatment chemicals, as well as in lower water and sewer costs. Use an ion- exchange regeneration system.

Improve the collection of copper and send the copper sulfate for recovery instead of storing it.

Install drip racks over the electrolytic plating baths, the acid soap bath, and the microetch bath. Lower consumption o f plating reagents, copper nuggets, and tin anodes will result.

Waste reduction = 1,650 gal/yr Cost savings = $4,03O/yr (net) Implementation cost = $10,000 Simple payback = 2.5 yr

Waste reduction = 1,015 gal/yr Cost savings = $1,84O/yr Ion-exchange saving = $6,50O/yr Implementation cost = $9,800 Simple payback = 1.2 yr

Waste reduction = 3,200 lb/yr Cost savings = $700/yr Emplementation cost = 0 Simple payback = immediate

Waste reduction = 10 gal/yr Cost savings = $275/yr Implementation cost = $200 Simple payback = 9 mo

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TOXICITY CHARACTERISTICS LEACHEATE PROCEDURE OR TCLP: AN OVERVIEW OF ITS EFFECT ON WASTE GENERATORS AND ITS METHODOLOGY

Kerry Prescott, Director AC Laboratories Inc.

6546 Pembroke Road Miramar, Florida 33023

General Overview of New Rule

Hazardous waste became more clearly defined for many industries on September 25, 1990. The existing Hazardous waste components list was amended and increased by twenty five ( 2 5 1 . Prior to this date, the Toxicity Characteristic list included eight (8) metals, four ( 4 ) pesticides and two ( 2 ) herbicides. The toxicity of a particular waste stream was evaluated using an Extraction Procedure (or E.P.1 Toxicity test and finding any constituent of this list above the regulatory level defined the waste stream as hazardous. Disposal restrictions are essentially defined by the character of the waste. The newly added components to the Hazardous Waste Characteristics list include solvents, phenols, chlorinated hydrocarbons and additional pesticides.

The most significant effect on industry will be the economic impact. Projected costs involved with compliance to this newly revi-ed rule will be from $150 - 5420 million dollars annually. These costs will be divided into:

( 1 ) re-characterization of waste, ( 2 ) actual reduction of a hazardous waste constituent

from a waste stream, and ( 3 1 disposal facility costs as some facilities become

unavailable due to new exceptance criteria.

The quantity of generated waste will determine a facility’s compliance date, namely:

(1) September 26, 1990 if a facility generates greater than 1000 kg of hazardous waste per month, or

(2) March 26, 1991 if a facility generates less than this amount and is classified as a small quantity generator.

The impact will not only be felt by the industrles and manufacturing facilities, but also by the previously non- regulated land based disposal facilities. By more clearly defining a waste that can be accepted, many more will have to seek additional restricted disposal facilities catering to a variety of newly classified wastes.

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The changes to the list are a result of the imposed responsibility. Subtitle C of the Resource Conservation and Recovery Act established a federal program with the responsibility to regulate hazardous waste. The hazardous waste was defined in the EPA Rule as a waste that may "pose a substantial present or potential hazard to human health and the environment when improperly treated, stored, transported, disposed or otherwise managed." The two major points are:

(1) defining hazardous waste, and ( 2 ) identifying scenarios of disposal mismanagement.

Regulatory levels had to be determined that were realistic both in application and as representing real human or environmental hazard. The actual regulatory levels the EPA arrived at are 100 times the current drinking water standards adopted in similar fashion to those regulatory levels determined for the E.P. Toxicity test parameters. The most crucial of a mismanagement scenario was determined to be a solid waste management facility. The EPA had the responsibility to determine a procedure of testing that was both current available technology and that fully simulated the leaching capabilities of a waste from a landfill facility to the underlying aquifer.

The responsibility to determine whether a waste exhibits hazardous characteristics falls primarily on the generators of said waste. Available and current testing protocols must be utilized to confirm a wastes exclusion or inclusion to a hazardous waste classification. The generators may, by rule provision, determine total concentrations first of waste. If values f o r total analysis fall below regulatory levels, and the specific requirements for the ultimate disposal facility will be satisfied with total values, the (T.C.L.P.) Toxicity Characteristic Leaching Procedure may not be required. Upon determining waste stream classifications, it is also the responsibility of the generators to, in their yearly manifest review reports, show there is a system in place to reduce hazardous waste accumulation and/or a particular component's presence in said waste stream. This report defines a reduction in human or environmental risk and should be kept with all documents pertaining to hazardous waste management control, transportation and disposal.

This new rule also provides incentives to assist in pollution prevention. By having a greater awareness of processes' components, substitutes can be found for hazardous waste management. Hazardous and non-hazardous materials must be kept separated because, essentially, a hazardous material plus a non-hazardous material yields a larger amount of hazardous material. If analysis reveals organics are a problem, carbon filters can be installed to eliminate this situation. All equipment used in

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processes should be well maintained to not only increase the equipment efficiency but to also eliminate unnecessary hazardous waster production.

The new regulations bring a greater awareness of the fragile state of harmony between man (i.e., business) and the preservation of the environment. Hopefully, the initial costs of complying with this new rule will decrease as greater efforts are made to reduce hazardous waste constituents.

Method Summary

The T.C.L.P. (Toxicity Characteristic Leacheate Procedure) attempts to simulate the migration of chemical constituents from solid waste landfill facilities or surface strata into the groundwater below. It is important to note, again, if "total" analysis of constituents in question are below regulatory levels, the T.C.L.P. may not be required.

The specific route on the analysis flow chart is primary dependent on the percent solid content of the waste. If no solids are present (less than 0.5 percent) the filtrate from a 0.6 - 0.8 non-fiber filtration is considered the "extract" for analysis purposes. For wastes containing greater than 0.5 percent solids, the liquid portion is separated from the solid content and this liquid is reserved for later use. The solid phase is extracted with twenty (20) times its weight of a minimum of one hundred (100) grams. The liquid filtrate is added to the reserve liquid and the combined sample is ready for analysis. If the two liquid phases are NOT compatible, they are each analyzed separately and a volume weighted average concentration is mathematically calculated. These are three distinct apparatuses involved in this new procedure:

(1) The agitation device - which allows for the sample to be subjected to an end over end agitation,

( 2 ) The zero headspace extractor (ZHE) - usually made of 316 stainless steel and uniquely designed for preparing volatile samples. This device ensures a liquid/solid extraction without headspace. The extraction vessel operates under pressure and with each analysis the sample preparation technician must ensure no loss compression. When other than volatiles are being sought, there is no need for a zero headspace extractor. Inert extraction containers, such as borosilicate glass (for organics) or PTFE (for inorganics), can be placed in rotation device.

( 3 ) The Filtration Device - after the samples have been agitated for sixteen (16) to twenty (20 hours, the material in the extraction device is separated using inert glass fiber filters in a filtration apparatus.

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Paints or oily materials are usually classified as solids and treated as such in the extraction procedure.

The proper extraction fluid is also crucial in this T.C.L.P. process. To determine which fluid to use, one performs some basic preliminary pH tests on the waste. If the pH of the waste is less than five (5) resulting from the test steps or if the organics and/or volatiles are being sought, Extraction Fluid number one ( # 1 ) is used. This extraction fluid is maintained at pH 4.93. Extraction Fluid number two (#2) is used for non- organics and for samples that, in the pH check, are greater than five ( 5 ) . This extraction fluid is maintained at 2.88.

As liming is not an ultimate stabilizer and produces highly alkaline wastes, the acidic nature of the extraction fluids attempts to address these waste products.

There is a network of people who can assist with any specific questions about the influence of this rule on specific wastestreams; namely

(1) RCRA Superfund Hotline - 1-800-424-9346 for rulemaking information;

(2) Region 4 EPA - ED Burke at (404)-347-2234 for questions to specific aspects of this rule.

(3) EPA Washington - Steve Cochran at (202)-475-8557 also for specific aspects if the Region IV representative is not available.

(4) EPA Washington - Gail Hensen at (202)-475-6722 for specific technical information about the Toxicity Characteristics Procedure.

Summary

In summary, the new Toxicity Characteristics rules affects most industry in reclassifying waste due to an inclusion of 25 additional "hazardous waste" definitives. This effect has far reaching economic impact on present waste streams as well as further industrial processes. This constituent inclusion obviously creates new "hazardous wastes" wastes that, before September 25, 1990 were not inherently classified as hazardous.

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Liquid Inlet/Outlet Valve

I I t

Pressure Gauge

Pressurized Gas InIet/outiet Valve

Zero-Headspace Extractor (ZHE)

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wmso

Extraction Vessel Holder

Rotary Agitation Apparatus

Federal Register / Vd. 55 No. 61 / Thursday. March 29, 1990 / Rules and Regulations

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METHOD 1311 FLOWCHART USE OF SUB-SAMPLE WASTE

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OLD LIST AmLrdEn

SUBSTANCE REGULATORY LEVEL SUBSTANCE (parts per million)

Xetals: Arsenic Barium Cadmium Chromium Lead Selenium Silver Mercury

Pesticides: Endrin Lindane Methoxychlor Toxaphene

Herbicides: 2t4, D 2,4,5, TP Silvex

5.00 100.00 1.00 5.00 5.00 1.00 5.00 2.00

0.02 0.40 10.00 0.50

10.00 1.00

REGULATORY LEVEL (parts per million

Benzene Carbon Tetrachloride Chlordane Chlorobenzene Chloroform 0-Cresol M-Cresol Cresol 1.4 dichlorobenzene 1.2 dichlorobenzene 1,l dichloroethylene 2,4 dintrotoluene Heptachlor Hexachlorobenzene Hexachloro 1,3 butadlene Hexachloroethane Methyl Ethyl Ketone Nirobenzene Pentachlorophenol Pyridine Tetrachloroethylene Trichloroethylene 2,4,5, Trichlorophenol 2,4,6, Trichlorophenol Vinyl Chloride

0.50 0.50 0.03

100.00 6.00

200.00 200.00 200.00 7.50 0.50 0.70 0.13 0.008 0.13 0.50 3.00

200.00 2.00

100.00 5.00 0.70 0.50

400.00 2.00 0.20

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ADDITIONAL CONSTITUENTS LISTED IN JUNE 13. 1986 RULE

GROUP 1:

GROUP 2:

ACRYLONITRILE BIS (2-CHLOROETHYL) EWER METHYLENE CHLORl DE

1 ,I ,I ,2-TETRACHLOROETHANE

1 ,I ,2,2-TETRACHLOROETHANE 1,1,1 -TETRACHLOROETHANE

1,1,2-TETRACHLOROETHANE

PHENOL 1,2-DlCHLOROBENZENE

CARBON DISULFIDE ISOBUTANOL

2,3,4,6- TETRACHLOROPHEN OL

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COMPREHENSIVE WASTE REDUCTION AT VON DUPRIN, INC.

Daniel Reinke, P.E. Capsule Environmental Engineering, Inc.

St. Paul, Minnesota

James Smith Von Duprin, Inc.

Indianapolis, Indiana

Michael Bayman Von Duprin, Inc.

Indianapolis, Indiana

Introduction

Von Duprin, Inc., located in Indianapolis, Indiana, is the market leader in supplying door exit hardware (panic bar devices). Von Duprin is a part of Worldwide Ingersoll-Rand Company’s Door Hardware group. In 1989 and 1990, Von Duprin, together with Capsule Environmental Engineering, Inc., an environmental consulting firm specializing in process waste reduction, developed and implemented a project designed to reduce wastewater sludges from plating operations by 90 percent.

Von Duprin’s plating operations include automated hoist rack plating of copper cyanide, satin and bright nickel, decorative chromium, brass cyanide, and also barrel plating of alkaline non-cyanide zinc. Von Duprin’s waste reduction efforts addressed methods to minimize and recover dragout from each of these process baths.

Initial Activities

Von Duprin initiated the project by having Capsule engineers review all waste generating operations to identify reduction opportunities. Activities included recommendation of specific equipment vendors where appropriate and development of economic analyses of various options.

Capsule began its work by reviewing the general characteristics of Von Duprin’s processes. Von Duprin had already implemented many important measures to reduce waste and associated costs, including:

* * *

Modifying rack designs to minimize cupping; Adjusting automatic hoist parameters to include extended drip times; Use of two-stage and three-stage counterflow rinses;

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* * Elimination of vapor degreasing.

Use of stagnant baths for recovery of dragout from bright nickel and chrome baths; Use of alkaline non-cyanide zinc bath to minimize use of cyanides; and

Capsule engineers measured dragout rates from all of the baths and compared this data with shop records on bath adds and production quantity records to develop sizing information on recovery equipment. This sizing information was sent to several vendors who were prequalified based on their equipment and experience with similar operations.

After obtaining equipment quotes, Capsule contacted users of the systems (not all of which were from the vendors reference lists) to learn more about the equipment and manufacturers. Capsule presented this information to Von Duprin management, who after serious review, charted a resolute course towards waste minimization at their manufacturing facility. The goal of this program was to make Von Duprin not only a leader in parts quality, but in environmental control as well.

Proces ses Se lected

1. Cyanide Copper. Technologies investigated for cyanide copper included spray rinsing, atmospheric evaporation, vacuum evaporation, electrolytic recovery from a stagnant rinse and reverse osmosis. Technical and economic evaluation of the options led to selection of a combination of spray rinses over the bath to further minimize dragout and atmospheric evaporation to make room in the bath for added water.

Advantages of this combination included maximum recovery of solution with minimal capital and operating costs. The simple technologies used mean less operator and maintenance attention than other options. An additional factor was that the fac i l i is contemplating the use of an alkaline non-cyanide copper plating, which may not be compatible with other options.

The disadvantage with this system, because of the use of the atmospheric evaporator on a cyanide bath, is the increased rate of buildup of potassium carbonate in the bath. Carbonate concentrations are regularly reviewed and treatment made when necessary.

2. Nickel. Technologies investigated for nickel recovery included spray rinsing, atmospheric evaporation, reverse osmosis, and several methods of ion- exchange. Technical and economic evaluation of the options led to the selection of a reciprocating bed ion-exchange system for recovery and reuse of a nickel chloride/nickel sulfate mix.

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Advantages of this option included the ability to recover the nickel from both the satin and bright nickel baths without fear of bath contamination associated with recovery of bath brighteners. The reciprocating bed design offered direct ability to reuse recovered solution without further processing to remove excess water.

The disadvantage of this system was a relatively high capital cost, although payback on the capital investment was very favorable - under two years.

3. Chrome. Technologies evaluated for chrome recovery included spray rinsing, atmospheric evaporation, and ion-exchange. Technical and economic evaluation led to the selection of a combination of spray rinsing, atmospheric evaporation, and a stagnant rinse to minimize dragout and recover solution captured in the first rinse.

Advantages of this system were the ability to greatly improve recovery with a minimal capital investment. This was especially important since the facility is contemplating switching to a trivalent chrome process for environmental reasons. The system selected was also seen to be applicable for a trivalent chrome system.

The primary disadvantage of this system was the buildup of impurities from reuse of the dragout. Ability of the existing tank steam coils to handle the heat loss from the evaporator was also found to be a problem after the system was installed.

4. Brass. Technologies evaluated for brass recovery included spray rinsing, atmospheric evaporation, vacuum evaporation, electrolytic recovery from a stagnant bath, and reverse osmosis. Technical and economic evaluation led to the selection of reverse osmosis to capture dragout and return clean water for rinsing.

Advantages of this system were the ability to close-loop the rinsing system, eliminating cyanide discharges. This positions Von Duprin to eliminate all cyanide in the wastewater when a non-cyanide copper process is implemented.

The disadvantages with this system include the high capital cost and operating costs of the equipment. Buildup of carbonates is also a concern, but this has not been observed at the plant.

5. Non-cyanide alkaline zinc. Technologies evaluated for this bath included ion-exchange, and reverse osmosis. Technical and economic evaluation led to the selection of reverse osmosis to capture dragout from this barrel line and atmospheric evaporators to make room in the bath for reuse of all of the recovered solution.

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The primary advantage of this system was the ability to close-loop the zinc system. Zinc provides the most difficulties in wastewater treatment, so eliminating this discharge was seen to ease end-of-pipe treatment. Another advantage of the reverse osmosis system was the ability to recover and reuse the zinc, unlike ion exchange systems which were designed to recover a zinc metal which would be shipped off-site.

The primary disadvantage of the reverse osmosis system was the lack of a good base of in-plant experience on the part of the vendor with this particular bath, although testing and a thorough review of the system indicated a high likelihood for success.

6. Peripheral equipment. As part of this project, process water for bath makeup and rinsing in the plating area was upgraded through the installation of a reverse osmosis water treatment system. Water produced by the reverse osmosis treatment system is then passed through rented mixed-bed deionizers to give the high quality (2 micromho) water necessary for bath adds and makeup for the zinc and brass recovery systems. The reverse osmosis system includes dual water softeners, cartridge filters, the reverse osmosis unit which uses polysulfone membranes, a holding tank, and repressure pumps. Both deionized water of 2 micromho or better quality and reverse osmosis water of 30 to 70 micromho quality are used in the plating area. The reverse osmosis water is used for most rinses.

Water use on rinses after cleaning and activation processes was reduced through the use of reactive rinsing. Water that was used to rinse parts after acid activation steps was pumped to rinse parts after compatible alkaline processes, such as electrocleaning. This reduces rinse water flows, improves rinsing after the electroclean bath, and reduces acid use since parts then entering the acid bath are neutralized or slightly acidic, rather than slightly alkaline. This was accomplished through the installation of in-tank pumps controlled by level sensors.

Eaubment Installation - Less0 ns Learned

The first system installed was the reverse osmosis water treatment line. The system was purchased with installation, startup and training, which helped make the installation proceed smoothly. One problem that developed, however, was a lack of constant adequate water pressure to feed the reverse osmosis unit, resulting in system shutdowns. This low pressure was first found to associated with a partially closed valve in the line feeding the system, but this did not fully solve the problem. The plating area is on the end of the plant water supply line, and heavy water use during shift changes and breaks seemed to cause low pressure shutdowns on the reverse osmosis system. Von Duprin

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investigated several measures to solve this problem, and settled on adding a new feed from the city supply directly to the plating area.

The second system installed was the nickel recovery ion-exchange system. This system was supplied with detailed drawings which were used to obtain installation quotes from local electrical and mechanical contractors. This system was installed smoothly, although piping contractors inappropriately mounted several transfer pumps outside of the diked area provided for the equipment. The major problems associated with the system included the control logic which had to be modified to allow smooth operation, and the rinse conductivities. On two of the nickel lines, operators added acid to the last rinse to activate the surface before chrome plating. Since the pH of these rinses varied based on the manual acid adds, the conductivity of the rinses varied. This caused difficulty in the control system, which determined nickel concentration in the rinses based on conductivity. Ultimately, this was solved by reducing the amount of acid used and adjusting the conductivity control loop for this acid level.

The next series of installations involved the reverse osmosis systems for brass and zinc. Substantial time was spent cleaning rinse tanks to remove hardness salts which could foul the reverse osmosis membranes. Both systems were provided with adequate installation diagrams, although some field modifications had to be made for piping lines. Extra costs were incurred to provide additional electrical noise isolation to protect system components. Equipment deliveries were delayed to allow negotiation of a purchase agreement with system performance guarantees.

The reverse osmosis installations proceeded smoothly, but several problems were found in the first few months of operation. A diatomaceous earth (DE) prefilter included on the zinc system repeatedly plugged with a hard deposit that also clogged piping to the DE filter. This clogging subsequently caused several failed prefilter pumps. Vendor analyses associated these problems with calcium carbonate in the system, coming from the use of insufficient quality water before installation of softeners and reverse osmosis membranes on the water supply. The calcium carbonate also apparently passed through the DE filter, plugging one set of reverse osmosis membranes. Von Duprin is still working with the vendor to identify and remove any sources of calcium to the plating system.

One major advantage was that the zinc and brass recovery systems are linked by phone modem to the vendor, who can then observe the system performance and modify program parameters to improve the quality of the recovered solution. On more than one occasion, however, vendor control of the system through the phone modem has resulted in spills from overfilled rinse or process tanks. Von Duprin has subsequently directed the vendor not to

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make program changes without preapproval from Von Duprin process engineering.

The last items to be installed were the spray rinses, evaporators, and transfer pumps for reactive rinsing. These items were all installed and wired with rough sketches prepared by equipment vendors and Von Duprin's consultant. Attempts were made to save the cost of preparing detailed drawings, however, in the long run it may have cost more due to rework required to make the systems operational. On startup of one of the chrome evaporators it was found that the existing bath heating system was fouled and could not provide the extra heat load from the evaporator. Within an hour, the temperature of the bath dropped enough to affect plating quality. Also, with both chrome recovery systems, the piping contractor used piping which failed when subjected to the warm chromic acid solution.

Svstem Performance

While all systems are still not fully operational on a continual basis, some reduction in sludge volumes has been seen. Additional dumping of cleaning baths and lack of consistent performance of the zinc reverse-osmosis recovery system have prevented the drastic sludge volume reductions that were expected, but further gains will be obtained as remaining recovery equipment problems are resolved. Increased plating sludge disposal costs associated with land ban regulations provided very positive, direct economic payback for economic justification of the recovery systems. In addition, Von Duprin anticipates positive publicity from implementing waste reduction technologies. By significantly reducing metals from the wastewater stream, Von Duprin also expects to provide continual compliance with present and future wastewater effluent limitations without excessive effort. Since problem components such as zinc and cyanides are being kept out of the wastewater stream, constantly increasing efforts will not be required to destroy or remove these materials. The other significant effect of reducing metals in the wastestream is reduced purchases of metal anodes and salts. Even with all systems not completely operational, metal usage in the third quarter of 1990 was less than half of that in the first quarter of 1990.

Summarv While there were and continue to be several problems to work out with the metal recovery systems installed at Von Duprin, the systems provide a cost- effective means to reduce waste generation and disposal costs, enhance community and customer relations, and reduce the potential for wastewater treatment upsets. Von Duprin effectively utilized the support of an independent environmental consultant knowledgeable in electroplating and metal finishing to provide them with the technical support necessary to identify and implement the

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various options. Von Duprin sees these activities as becoming more important in the future with tightening wastewater discharge levels, and spiraling wastewater treatment sludge disposal costs.

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