SOURCE REDUCTION POTENTIAL IN THE IRON AND STEEL WIRE DRAWING INDUSTRY SIC-3315

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1 SOURCE REDUCTON POTENTAL N THE RON AND STEEL WRE DRAWNG NDUSTRY SC-3315 prepared by: Gregory R. Jordan under contract to the Department of Environmental Management Bureau of Solid Waste Disposal March 1985

2 *. ABSTRACT "The goal o'f this manual is to describe Source Reduction techniques available to the ron and Steel Wire Drawing ndustry. Source Reduction (SR) is defined as on-site activities that reduce the production of hazardous waste at the point of generation. Source Reduction includes good housekeeping practices, process modification, product substitution, waste segregation, reuse and recycling. Federal, state and local governments are reinforcing legislation restricting the disposal of heavy metals from the plating industry into POTW's, surface waters and landfills. These regulations are limiting the availability of disposal options and increasing the costs of handling hazardous waste. Source Reduction is a waste management option that can help you comply or avoid costs associated with these regulations.

3 NTRODUCTON The Massachusetts Hazardous Waste Source Reduction Program conducted by the Department of Environmental Management (DEM), Bureau of Solid Waste Disposal (BSWD), encourages an alternative plan to conventional Fiazardous waste management, DEM's efforts to encourage Source Reduction include the following elements: * Source Reduction Advisory Committee - provides DEM with technical assistance in the planning and implementation of the Source Reduction Program, * Statewide survey- conducted by GCA Technology Division (consultants) to provide data on hazardous waste generation and source reduction practices in Massachusetts. * Two source reduction conferences and exhibitions (October 1983 and 1984) and two wastestream-specific seminars on Metallic Wastes in May 1984, the second in June 1984 on Solvent Wastes. * Coalitions- (The Mass, Coalition for Safe Waste Management Program) funding provided to local, citizen, environmental and industry interest groups to promote public, participation and education of the State's Source Reduction prog r am, * ndustry-specific technical assistance manuals such as this one, provide information on available source reduction techniques. WHY SOURCE REDUCTON Does source reduction (SR) reduce treatment and disposal needs? The answer to this question is a resounding YES. Source reduction processes offer benefits in the following areas: * Under the reauthorization of the Resource Conservation and Recovery Act (RCRA, PL98-616, Nov.8, 1984), the EPA will be restricting land disposal of specific waste and liquids and encouraging "waste minimization" processes. * Decreases the Commonwealth's shortfall capacity for land disposal and the variety of technologies required to handle its hazardous waste stream. * Decreases &&endency on land disposal, associated costs and liabilities. EPA estimates the clean-up cost of improperly disposed waste to be $2,00O/ton, while the cost of disposing waste in accordance with RCRA is only $90/ton.

4 * Minimizes generator liability under the Comprehensive Environmental Response, Compensation and Liability A C E 1980 (CERCLA), better known as Superfund. A generator is liable for the disposal of his hazardous waste to a licensed disposal facility. (Public Law , Sec.107, Liability). * Decreases dependency on raw materials through reuse and recycling. For example, a company purchases oils at a cost of $2.00 to $4.00 per gallon. Disposal costs for used oil are approximately $1.00 per gallon. An on-site waste oil reclamation system recovers 95% of the oil at an average cost of.$30 per gallon. Using the oil recovery system, the generator saves a net $2.70 to $4.70 per gallon. * Minimize the impact of "Right to Know" legislation through substitution with less toxic raw materials. WHAT S SOURCE REDUCTON Source Reduction is a preventive waste management strategy requiring a commitment on behalf of corporate management. Source reduction techniques include: * Good housekeepins practices resulting in the reduction of wastes produced and raw materials consumed. Examples: adequate preventative maintanence program; eliminating excessive water usage; minimize leaking and spillage of tanks, valves and pumps. * Product Substitution involving the replacement of hazardous waste-intensive products by a new product that eliminates or reduces the generation of hazardous waste. Examples: replacing chromic acid cleaners with sulphuric acid and hydrogen peroxide cleaners. * Waste Sesresation separating hazardous from nonhazardous waste streams. Examples: separation of process and noncontact cooling waters; avoid mixing a recoverable solvent with a nonrecoverable waste. * Process Modification requiring altering a waste producing industrial process to minimize the amount of waste being generated. Examples: eliminate acid pickling operation with mechanical descaling system, eliminating hazardous waste generation of spent acid. * Reuse and Recvclinq include the use of a waste without prior treatment (reuse) and use of a waste after some form of treatment (recycling). Example: Reuse- solvents used in the electronics industry for cleaning are slightly

5 contaminated and can be used directly by the paint industry without prior treatment. Recycling- reclaiming wastejeoil for use as a fuel supplement. * Waste Exchanqes (technically not source reduction) promote the reuse and recycling of hazardous waste by matching generators with companies that can use their waste in their production process. Examples: The Northeast ndustrial Waste Exchange and the California Waste Exchange. MASSACHUSETTS WASTE STREAM According to the Directory of Massachusetts Manufacturers, thirteen firms are listed as ron and Steel Wire Drawing firms, SC Code Wastes generated by this industry include: * DOO1- solid wastes that exhibit the characteristic of ignitibility. Examples are waste oils and solvents. * K062- spent pickle liquor from the steel finishing operations. * Others- Heavy metal sludges generated during the treatment process containing arsenic, cadmium, chromium, lead, mercury and other metals listed in 40 CFR 261 of the Federal Register.

6 SOURCE REDUCTON TECHNQUES METAL RECOVERY Various methods of recovery--electrolytic recovery, ion exchange, evaporation and membrane technologies such as reverse osomosis and electrodialysis--have been investigated for the recovery of metals from plating wastes and rinse waters. Relatively simple measures can drastically reduce the amount of waste requiring treatment and disposal and optimize, by concentrating, the metals for recovery: * Minimizing dragout from plating bath. * Segregating waste streams to facilitate recovery of plating solution and rinsewaters. * Using water conservation as a technique will lead to significant source reduction. For example, multi-tank countercurrent rinsing systems such as the "Providence Method" [Fig.l] reduce water consumption by as much as 95% (depending on the number of rinse tanks). This process uses the dirtiest (most contaminated) rinse tank as a source for metals recovery. Once these prerecovery techniques are implemented, valuable resources from your hazardous waste stream can be recovered by utilizing the following waste reclamation technologies: * Electrolvsis: an oxidation/reduction process separating positively and negatively charged ions by the application of an electric current. This process is used in the recovery of gold, silver, tin, copper, zinc and cadmium. The metals are recovered and resold. Example: as an alternative to batch treatment of copper and stannous sulfate plating baths, electrolytic metal recovery process is employed. Economics: capital costs for a small package treatment plant having a flow rate of 315 to 400 gallons per hour is in the range of $20,000 to $25,000. * on exchanse: a process for separating dissolved inorganic material from an aqueous solution. Liquid is passed through a fixed bed containing a natural or synthetic resin. The resin exchanges ions with the inorganics in solution, resulting in the removal of the inorganics and their attachment to the resin column. Example: utilizing a closed-looped countercurrent rinsing system and an ion exchange column,'the rinse waters of a bronze plating line are reclaimed for reuse and the captured metals, eluted from the resin column, are sold for. $.35 to $.40 per pound.

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8 Economics: in the metal finishing industry, most of *%he waste.water requiring treatment results from rinsing operations. Selective treatment and reuse of rinse streams by ion exchange can result in a considerable savings in the investment necessary for end-of-pipe treatment systems. Unit cost are dependent on flow and can be minimized by employing water conservation techniques. * Evaporation: an established economical concentration and volume reduction process where a liquid (usually water) is driven out of a solution through the application of heat. The feed to the evaporator is the discharge from the first countercurrent rinse tank after the plating tank. Recovery is accomplished by boiling off sufficient water from the feed rinsewater stream to allow the concentrate to be returned to the plating bath. This process is frequently carried out under vacuum to conserve energy and prevent thermal degradation of the plating bath constitutents. Example: can be used in many plating lines to reclaim plating bath solutions and rinsewaters. Economics: evaporators represent an economically viable waste processing technique especially when heat is available. Capital cost is depende,nt upon the type and quantity of waste to be evaporated, it's toxicity and volatility. Maintenance costs are relatively low. * Reverse osmosis: pressure is applied to the more concentrated side of a semipermeable membrane, causing the permeate (mainly water) to diffuse through the membrane in the direction opposite the osmotic pressure. The concentrated solution of dissolved solids left behind can be further treated to achieve a more concentrated solution (evaporation) or returned to the plating bath. The permeate goes to the last rinse tank, providing water for the rinsing operation. Example: the use of a 100 gallon/hour reverse osmosis unit to recover nickel plating chemicals for reuse. Economics: capital costs range from $.49-$3.80 per gallon per day of purified water output, depending on the volume of waste to be treated. Total operating costs are $1.00-$5.00 per 1000 gallons. WASTE OL RECLAMATON Waste oils offer a tremendous recycling potential. An important consideration is segregation of different waste oils to accommodate reclamation for reuse. An available on-site technique to reclaim waste oil is:

9 * Portable purification systems which process waste oils by xwwuviin~ wakex r~awe~4% taminattii,tm,mad scddds.,3.b average cost to reclaim is $.30/gallon compared to virgin oil cost of $2-$4.00 per gallon. Recovered waste oil can be used in the following areas: * burned as a fuel supplement * reused in original function * sold to an independant rerefiner. ACD RECLAMATON During finishing operations, scale and undesirable surface contaminants must be removed from the steel surface prior to the metal plating process. Acid pickling solutions, usually Hydrochloric or Sulphuric are employed. The wastes generated by lime or caustic neutralization render total acid loss and large volumes of sludge requiring disposal. Options available for reclaiming the acid include the following: * Sulahuric Acid recoverv The spent pickle liquor (SPL), high in iron, is pumped into a crystallizer that precipitates the iron as ferrous sulphate heptahydrate using refrigeration or vacuum. Water is removed and the free acid content increases to a reusable level. The acid is then pumped back to the pickling bath. After drying, the byproduct, ferrous sulphate heptahydrate is marketable for use in the manufacturing of inks, dyes, paints and as a coagulant in water and wastewater treatment. * Hydrochloric Acid recovery [Fig.2] The acid is recovered by heating to 925*C to 1050*C to evaporate the water and decompose the ferrous chloride to ferric oxide and hydrogen chloride gas. Ferric oxide is mechanically separated and removed from the system by discharging through the bottom of the reactor chamber. Hydrogen chloride is reabsorbed in water to produce hydrochloric acid (generally 15-21% HC1). The acid is pumped back to the pickling tank.

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11 The byproduct, ferric oxide, is used in the manufacture of pigments, ferrite and magnetic tapes, fertilizer and animal feed. A steel company in Canada has been successfully regenerating spent hydrochloric acid using this process since Alternate techniques include mechanical descaling and abrasive blasting of surfaces to remove contaminants. Economics: Sulfuric acid regenerating systems require lower capital costs and energy requirements than hydrochloric acid reclamation systems. Variabilities in operating conditions and in the availability of land among pickling facilities must be considered in evaluating the economics of each process. At pickling capacities above 75,000 tons per year, the acid recovery processes appear to be the most economical choice. CONCLUSON Given the potential for significant liabilities and damages to health and the environment resulting from inappropriate waste management practices, careful attention should be paid to proper waste management including implementation of a source reduction program. Source reduction will decrease the quantity of hazardous waste requiring off-site treatment and disposal and will reduce potential long term liability associated with hazardous waste disposal. Source. reduction strategies including reuse and recycling techniques offer substantial benefits: decrease dependence on TSDF's conserve resources minimize regulatory and financial impact * decrease operation and maintanance costs * decrease water and sewer-user fees hazardous waste. * minimize employee, public and environmental exposure to * reduce the generation of hazardous waste HAZARDOUS WASTE CAN BE A VALUABLE RESOURCE TO GENERATORS WHO ADOPT SOURCE REDUCTON AS A KEY ELEMENT N THER HAZARDOUS WASTE MANAGEMENT PROGRAMS!!!

12 a 5) 6) 7) BBLOGRAPHY Technologies and Management Strategies for Hazardous Waste Control; Congress of the United States, ffice of Technology Assessment, March Campbell and Glenn; Profit from Pollution Prevention; Toronto, Canada, Massachusetts Hazardous Waste Source Reduction Conference Proceedings; Bureau of Solid Waste Disposal, Oct.17,1984. Hazardous Waste Management in Massachusetts- Statewide Environmental mpact Report; Massachusetts Department of Environmental Management, Bureau of Solid Waste Disposal, Generic Process Technologies Studies; Ontario Waste Management Corporation, August Laughlin, Forrestall and McKim; Primary Metals ndustry Technical Manual Waste Abatement, Reuse, Recycling and Reduction Opportunities in ndustry, January Camp, Dresser and McKee, nc.; Technical nput for the 1984 Hazardous Waste Generic Environmental mpact Report (GER) Final Report, November, 1984 F.A. Steward, ERC/Lancy; Conservation and Recovery of Materials and Treatment of Waste, n-process Pollution Abatement- Upgrading Metal Finishing Facilities to Reduce Pollution; USEPA Technology Transfer, Directory of Massachusetts Manufacturers, Edition; George D. Hall Company, 1983