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Show Specifically, the scrap is heated in the same buckets that are normally used to transi 3r scrap to the EAF within the "minimill." The scrap bucket is placed in a heating chamber and hot gases from a "rich fume reactor" (RFR) are forced through the bucket heating the scrap. Oil clinging to ste.el is volatized and directed to the RFR. The RFR provides the energy for preheating. Volatized oil vapors and natural gas 2. 3 combusted in the reactor providing a hot, low oxygen gas stream. The hot RFR exhaust gases are directed to the scrap bucket where more oil is volatized. Becaus of the low oxygen content of the RFR exhaust the oil on the scrap will not burn. Whf: 1 a predetermined temperature has been reached, the bucket is removed and the hot scrap transferred to the EAF. Surface Combustion estimates that well over 90% of cutting oils present on the scrap will be volatized, to be subsequently combusted in the RFR. That the process is relatively low emitting is shown in the emissions projections which follow. Projected Emissions for Stainless Steel Preheater Component NOx SOx CO VOC HCI Total particulate Concentration 102 ppm 59 ppm 2 ppm 2 ppm <2 ppm 0.0038 grains/dscf Energy and monetary savings are expected to result from reduced electricity consumption, reduced electrode usage and refractory near, the ability to process a lower cost scrap and increased productivity. Surface Combustion expects to demonstrate this system at a minimill owned by Washington Steel. Workpiece Temperature Analyzer DOE is sponsoring the development of non-contact acoustic technologies to measur~ accurately the temperature a workpiece in an industrial furnace. The goal of these activities is an instrument and control system which will decrease energy input, increase productivity, reduce overall costs and improve product quality in heat treati r. ~ industries. This year DOE has sponsored two contractor teams: Surface CombustioniTextron, and Babcock & Wilcox/Johns Hopkins in this area. The approach being used is to impact the workpiece with a relatively high power laser thereby establishing a sonic vibration which passes through the workpiece like a wa 3. For a given material, the "time of flight" will be related to temperature. The arrival of the sound wave at a location remote from the impact can be established using a lasE(based interferometer. |