Pollution prevention: a winning strategy for industry

Lockheed Martin Naval Electronics & Surveillance Systems—Syracuse

by Yvonne Slate, NYSDEC Environmental Health and Safety Specialist

Lockheed Martin Naval Electronics & Surveillance Systems, Syracuse manufactures airborne and ground-based radar, sonar, undersea systems, and marine traffic management equipment. Its 2200 employees are responsible for electronics manufacturing, systems assembly, and systems integration.

Through funding from the Defense Advanced Research Projects, Lockheed Martin and General Electric Corporate Research and Development sought ways to eliminate the ozone depleting chemical freon from soldering. The goal was to develop a no-clean soldering process for surface mount assemblies suitable for military application that would eliminate post-solder defluxing. This companies partnered with Alpha Metals, Inc. and Binghhamton University.

A baseline was established to understand the state of the art electronic processing and solder pastes, specifically commercial no-clean solder pastes. A suitable test coupon was developed to address the critical factors (electrical, mechanical, and thermal) of the no-clean soldering process; the technical literature of both no-clean and no-residue solder pastes was reviewed; and, the performance of ten different solder pastes was evaluated. The three best pastes were tested extensively and evaluated to select the most suitable paste. Two additional Lockheed Martin sites in New Jersey and Florida were enlisted to manufacture and test several assemblies. To prepare for customer acceptance of this process, detailed performance data were collected at each site.

The advantages of the no-clean solder process were presented to military programs. Contractual and process changes were initiated to permit their use. Lockheed Martin representatives also worked with other Lockheed Martin and GE locations, the Department of Defense, and government and industry groups to explain advantages of the no-clean solder process technology.

Benefits from this P2 initiative included:

• No negative effect on quality or producibility
• Use of isopropyl alcohol was reduced almost 90%.
• Two hazardous waste streams, spent solvents and cleaning debris were reduced early 90%. No new waste streams were generated.
• Waste disposal costs were reduced by 85% saving over $6700 in the past 2 years.
• Cycle time was reduced 12% for electronic assemblies because cleaning steps were eliminated, equaling $270,000 savings in labor in 1996 and 1997. Full implementation resulted in $806,000 labor savings in 1998.
• An additional $10,428 in raw material savings was realized.

Other economic benefits that resulted from this process include reductions in costs associated with hazardous waste disposal liability, waste reporting and tracking requirements, and raw material and waste handling. Employee safety has improved because of reduced chemical exposure, less risk of spills and releases, and reduced environmental and public health risks associated with waste treatment, land disposal and incineration.

Carrier Corporation, Dewitt, New York

by Elizabeth Hubben, Environmental Manager and Philip Talucci, Environmental Engineer

Carrier Corporation employs 4100 people in Syracuse. It manufactures a variety of refrigeration machinery. An integral part of Carrier's manufacturing process is the use of machining equipment for drilling cutting and grinding. The friction between the tooling and the metal being shaped generates heat. Machine coolants in the form of oil/water emulsions are sprayed on the part to reduce friction, dissipate heat, and flush metal chips from the tool contact areas. The use of the coolant results in cleaner machining and longer tool life, but generates large amounts of spent coolant which requires treatment and disposal.

In 1991, Carrier installed an ultrafiltration treatment plant designed to process coolants and alkaline wash waters by separating and concentrating the oils. The quantity of effluent oil generated by the treatment system is affected by the volume of coolants in the wastewater being treated and by the efficiency of the ultrafiltration system. Carrier first looked at reducing the quantity of oil generated while increasing its quality (Btu value). The modifications included better scheduling of the incoming coolants and wash waters, routine de-watering of the oil tank, and increased attention to operational and maintenance details of the ultrafiltration system. These basic modifications saved $70,000/yr. Carrier's next goal was to reduce the amount of water and coolant being processed in the ultrafiltration treatment plant.

Carrier recognized that machine coolants cost many thousands of dollars each year in raw material, labor, and waste treatment. During 1996 Carrier generated over half a million gallons of coolant waste costing $68,000 for treatment and requiring off-site treatment of over 30,000 gal of concentrated oil. Including labor for handling drums, testing at each sump, adjusting coolant concentration, and routine clean out of each machine sump, the total cost of managing coolant waste was over $950,000. A team was formed to examine a way to maintain or increase the quality of machining operations while reducing water usage and coolant burden.

The team determined that the Carrier plant was typical of many large industrial machine shops. The plant had over one hundred individual machine (stand alone) sumps providing coolant to a machine or group of machines. Four different vendors supplied ten different machine coolants, and each machine had a specification written for the type and concentration of coolant to be used. In addition, many of the coolant concentrations were checked and found to be out of specification. The team concluded that to meet the goal of reducing wastewater generation, the number of coolant sumps and staff maintaining the quality of the coolants would have to be reduced. The solution was to use a central coolant system to eliminate individual sumps. The central tank provides coolant to a large number of machines and typically collects the used coolant along with chips and metal fines removed during the machining process. Typical applications utilize pumps and over head piping to supply coolants to machines and a trench or flume system returns the coolant and chips to a below-grade tank. Recently, however, complete above-grade systems have become more popular because they eliminate the need for expensive floor trenching and below-grade excavation. they are also more flexible should machines need to be removed or replaced.

The disadvantages of a central coolant system were also evaluated. Potential problems included the shut down of a series of machines if there was a problem with the system, large quantities of waste water being treated at one time, and potential increase in bacterial or fungal contaminants in the coolant because of the longer effective coolant life.

In 1997, Carrier began installing central coolant systems. Currently three are in operation. As a result, 80% of the stand alone sumps have been eliminated. The three systems also use only one type of coolant supplied by one vendor. A fourth central coolant system will be installed this year. The central coolant systems in Carrier's application have a 3.9-year payback. As a result, the machining problems arising from inconsistent coolants have been virtually eliminated. Machining areas supplied by the central coolant system are cleaner and less cluttered with drums, pumps, sumps, chip carts, mops and buckets providing a better working environment for staff.

Additional benefits resulting from this P2 initiative included:

• Coolant is bled continuously for treatment to remove tramp oils in a centrifuge.
• Tank levels are controlled automatically providing a uniform flow to the machines.
• Coolant concentration is controlled from a central point saving time, raw material, and water.
• Sump cleaning and chip removal at individual machines is virtually eliminated.
• Waste treatment flow is predictable.
• Piping and trench covers reduce the opportunity for coolant contaminates, such as lube/hydraulic oils and maintenance detergents, to enter the system and shorten the coolants effective life.
• The amount of wastewater treated has been reduced by 300,000 gal/yr.
• If properly maintained, central coolant systems enables the coolant to be reused.

Alox Corporation, Niagara Falls

by Richard Schamberger, Plant Manager

Alox Corporation, Niagara Falls, markets corrosion inhibitors to compound blenders of metalworking fluids, rust preventatives, aerosol products, and industrial coatings. Alox does not sell finished goods; products made from Alox additives are sold under many trade names worldwide.

A methanol reduction/recycling project was undertaken to reduce the amount of soluble organic compounds in the sewer outflow to the Niagara Falls Waste Water Treatment Plant. The previous sent contaminated methanol to the sewer. The project also decreased the amount of raw material required. Reuse of what was formally contaminated methanol increased efficiency by reducing the amount of methanol by approximately 50%.

The project involves the recovery of methanol and recycling through distillation. The recovery step of the distillation process is unique. A major intermediate product for the production of corrosion inhibitors is a methyl ester of the base acid. For many years the practice has been to use methyl alcohol in excess to drive the reaction to completion. The formation of water during the reaction slows and finally stops the reaction. It had been assumed that product specifications could not be achieved without a large excess of alcohol.

A long series of reactions and tests were first performed in the laboratory. Equipment was set up to simulate the injection of methanol into the base acid that was heated to a temperature above the boiling point of methanol. Exact plant conditions could not be simulated, but the results were promising enough to continue work.

Following the positive lab tests, trial runs moved into the plant. This was accomplished by slowly injecting methanol into a line circulating the base acid. Although the base temperature was above the boiling point of methanol, the slightly increased pressure in the circulation line kept it in contact with the acid and allowed the reaction to occur. When the mixture in the circulation line was returned to the reaction vessel, the methanol evaporates, carrying the water of the reaction with it. This vapor mixture was condensed and sent to a holding tank which pumped the water-alcohol mixture to a distillation column. The methanol was recovered through distillation and returned to the tank used to inject it into the reactor. What was created was a unique closed-loop system with methanol being reused and water going to the sewer.

Over 30 different test runs were made and studied in the plant to establish initial conditions, temperature requirements and raw material injection rates into the base material. Tests were simultaneously performed on final products to assure that quality specifications were met.

The benefits resulting from this P2 initiative included:

• The modified production approach reduced the amount of methyl alcohol required from approximately 2180 lb/batch to 1090 lb/batch, a 50% reduction.
• Raw material savings amount to approximately $31,000/yr based on current prices.
• Formerly, the excess methyl alcohol was being sent to the sewer and subsequently to the Niagara Falls Waste Water Treatment Plant. This is a batch process with production occurring once a day, five days a week annually. The new

resulted in

• reduction of over 280,000 lb/yr of excess methanol.
• Reduction in sewer fees are estimated at $40,000 annually.
• As a premium, the new production procedure does not require added manpower or time. Also, the same high quality (ISO 9001) products are being manufactured.

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Tanya Lahr, PE is an Environmental Engineer 2 with the NYSDEC, Pollution Prevention Unit.