Waste Minimization Assessment for a Manufacturer of Refurbished Railcar Bearing Assemblies

摘要

The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected universities and procedures were adapted from the EPA Waste Minimization Opportunity Assessment Manual (EPA/625/7-88/003, July 1988). The WMAC team at the University of Tennessee performed an assessment at a plant which rebuilds railcar bearing assemblies -- approximately 163,200 bearing components per year. Bearings are disassembled, washed, then inspected. 'Premium' bearings, those still within specifications, are reassembled with new grease and bearing seals, packaged and shipped. Non-premium bearings are buffed, rinsed in hot water, and then chrome plated to build up the bearing surfaces. After chroming, the parts are rinsed, baked, and allowed to air cool. Cooled bearings are reassembled with new grease and seals, then packaged and shipped. The team's report, detailing findings and recommendations, indicated that the majority of waste was generated during the railcar bearing cleaning operation and that the greatest savings could be obtained by instigating onsite wastewater treatment and recirculating recovered water to reduce (90 percent) water consumption in the railcar bearing cleaning operation.