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Show INDIRECT FIRED FLAT RADIANT PANELS Harry S. Kurek, Vladimir Kunc. Yaroslav Chudnovsky Institute of Gas Technology Chicago, Illinois, U S A Antonin Touzet, Antoine de La Faire, Thierry Landais Gaz de France Saint-Denis la Plaine, France Anatoly E. Erinov, Aleksei M. Semernin Gas Institute of the National Academy of Sciences of Ukraine Kiev, Ukraine Abstract During the last two decades, global energy and market conditions have motivated the thermal processing industry to improve energy utilization in order to remain competitive. To meet these demands, research in the thermal processing industry has been directed toward one or more of the following: 1) improving process productivity, 2) improving process temperature uniformity, 3) improving product quality, 4) improving thermal efficiency, and 5) reducing air toxic emissions. The Institute of Gas Technology (IGT), Gaz de France (GDF) and the Gas Institute (GI) of the National Academy of Sciences of Ukraine have joined to demonstrate and commercialize a technology developed by GI - an indirect gas-fired, low-inertia/high-efficiency furnace - which is consistent with and meets all five of the criteria above. The base technology has been evaluated for the heat treatment of products in the machine manufacturing industries (for example, gears, bolts, shafts, etc.). The technology, however, might also be feasible for indirect-fired drying applications (for example, powder paint and paper). The unique design of the low-inertia furnace, that utilizes high thermal efficiency indirect-fired flat radiant panels, promotes high heat-up rates, excellent temperature uniformity, high thermal efficiency, and low emissions. Thus by applying this technology, the end user can benefit from increased productivity, improved part quality, reduced fuel consumption, emissions abatement, and reduced capital and operating costs. Introduction In many metallurgical processes, such as heat-treating of steel, the product must be heated in a protective atmosphere containing H2. N 2 , and C O , and negligible amounts of 0 2 and H 2 0 . If fossil fuel (natural gas is most common) is used to provide the heat, the combustion products must, therefore, be kept separated from the atmosphere. Similarly, many drying applications - powder painting, paper, etc. - also benefit from keeping the combustion gases separated from the combustion products. Since heat treating is a significantly higher temperature process than drying, it constitutes a more severe application for indirect-fired systems. The most common approach currently utilized in heat treating furnaces is a radiant tube combustion system. The radiant tubes, in which the natural gas is fired, are generally made from Ni/Cr alloys, and can operate at temperatures up to 2000°F. Failure of the tube may occur above this temperature from high-temperature oxidation, creep, carburization/embrittlement. |