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pp 2 of 2 The Sheller furnace was not in service during my visit. It was down for refractory repairs and replacement. The propane burner is rated at 3 MM BTU/hr. The average propane consumption is 30 gph which results in burner heat release of 2.75 MM ETU/hr. The recovered aluminum requires approximately 840,000 BTU/hr, the scrap iron approximately 110,000 BTU/hr and the heat loss was estimated at 100,000 BTU/hr resulting in a net difference of appro~-~imately 1.95 MM BTU/hr discharged from the furnace with the burner at maximum rate. PARTICULATE REMOVAL The existing water spray is an inefficient method of removing particulates from a flue gas stream. The existing stack from your reverberatory furnace was observed to be clear. However, since a charge of dirty scrap could result in stack emissions, our recommendation is to install a baghouse filter to remove the particulates that can be generated ~rom your recovery process. A baghouse installation requires an influent gas stream that is above the dew point to prevent wetting of the filter bags. We therefore recommend that the water sprays be removed from the Shaffer Furnace and that the flue gases be cooled by air dilution to attain the proper baghouse inlet temperatures of from 250 to 300 F. During the summer,the cooling air required to lower the baghouse inlet temperature to 300 F is 8400 SCFM with the furnace burner' operating at its rated capacity o~ 3 F~q BTU/hr. The products of combustion from the propane ~re 510 SCFM resu!tin9 in a total required gas flow of 8910 SCFM or 13,000 CFM at 300 F. A portion of the cooling air enters the system via the hood above the furnace. The balance of the air required will De introduced to the suction~^= the blower through a damper inlet valve. The =~' ~ue gas inlet loading is expected to be low by our ~e~e observations. A filter bag ~as ratio to square area will be approximately 9:1 resulting in a baghouse sizing of approximately 1500 Ft ~ The process involves aluminum w~=~h -~ ~=~ light metal. Therefore, the baghouse must be installed outdoors and away from the building in order to be within the fire codes.