Kelly Air Force Base
The plating shop in bldg. 301 uses aluminum oxide blasting media to strip and clean parts in preparation for plating. The blast media is collected in a common collection system as the particles wear and are reduced in size. The waste media is sampled to determine if the blast media is characteristicily a hazardous waste. Reclaim efficiency was found to be only approximately IO%, this generating a large volume of waste.
The project involves replacing two aluminum oxide blasting machines that were beyond economic repair and reconditioned seven other machines to a sound operating condition. To enable proper calibration of the blasting machines, all machines were provided with externally adjustable cyclone vortex tubes and air flow dampers for the respective blast media reclaim units. This allowed optimization of the internal media reclamation efficiency and reduced undue consumption of aluminum oxide grit, while maintaining good visibility in the blast cabinets. Two machines were separated from the common waste exhaust system, and a dedicated dust collector was installed on each machine. This segregated the hazardous from the non-hazardous waste materials, thus reducing the amount of hazardous waste generated.
The upgrade of aluminum oxide blasting system allowed the unit to operate more efficiently and reduce future maintenance cost by segregating waste streams. An overall reclaim efficiency of the system is 90%
The project allowed the reduction of the waste streams in accordance with RCRA requirements. Hazardous waste disposal was reduced by approximately 60% and reduction blast media purchase is approximately 80%.
Details of Reductions
Additional Information :
The project has an economic reduction of $180,000/yr for blast media purchases and $26,000/yr in hazardous waste disposal.