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Show REGEN REGENERATIVE BURNER FOR HIGH PERFORMANCE, HEAT RECOVERY IN AGGRESSIVE ENVIRONMENTS John N. Newby Regen Systems, Inc. Lexington, Kentucky, USA ABSTRACT The reGen Regenerative Burner, an all ceramic high temperature burner, close coupled to a compact, fast cycle, ceramic regenerator, provides air prehea ts in excess of 85% of the process temperature in fuel fired applications up to 1 650 0 C (30000 F ). The unit is operating without problems in dirty waste gas applications such as aluminum reverberatory melting furnaces and a soda lime glass melting tank, where the exhaust gases contain high volatile and particulate loadings of a corrosive and condensing nature. In these production environments, and others such as ingot reheat i ng for forg i ng wh ich fa II on the borderline between "dirty" and "clean" waste gas classifications, the substantial performance, life and ease of maintenance advantages of this design and concept over recuperation have been demonstrated on a commercial basis since the first installation on a glass melting furnace in January 1983. This paper describes the equipment, its operating phi losophy and performance. Examples of melti ng and reheating applications in the metals and glass industries will indicate the suitability of reGen for retrofit as well as new construction, and reinforce the flexibility afforded by its des i g nan d con s t r u c t'i 0 n , inc Iud i n g m u I t i - f u e I capability, high, medium, and low velocity burner designs, and remote mounting of regenerators, and discuss the various cleaning methods used to remove fouling from the regenerator packing. Fuel savings, over cold air operation, ranging from 40% to 65% are reported from applications where well controlled and maintained conditions ex' is ted be for ere G e n was ins t a I led. The s e , combined with the "no process compromise" afforded by reGen's design flexibility, offer the user a cost effecti ve means of addressi ng exhaust heat recovery in even the toughest appl ications. n THE EQUIPMENT described in this paper comes from the third stage of a development program aimed at producing high performance heat recovery equipment for industrial furnaces, capable of operating over a wide range of temperature in both c lean and di rty waste gas environments, suitable for application to a wide range of process furnaces without major furnace modHication and, above all, providing good return on investment by a sensible balance of performance and ma i ntenance needs. The first two stages concentrated on burners with integral recuperators. The first stage, in the middle 60's, produced equipment that was not economically viable because of the relatively low prevai ling fuel pri.ces. That equipment may also be viewed with some amusement from . today's materials standpoint - the choice of suitable a I loy s has wid e ned sub s t a rft i a I I yin the i nterven i ng years. The second phase was stimulated by the rapid increase in fuel prices in the early 70's. It produced economically viable equipment utilizing the latest commerci~lly available materials, but the units suffered the inherent low recovery performance of recuperators and thei r d i ff icu It ies with handling dirty waste gas streams. Hence this third stage - heat recovery performance approaching the ultimate theoretical and virtual insensitivity to operating environment. WHAT IS A REGENERATIVE BURNER? The Regenerative Burner consists of an all ceramic high temperature burner close coupled to a compact, fast cyc Ie, ceram ic regenerator. The burner serves double duty, acting also as the exhaust port and flueway from the fired chamber. One complete reGen unit comprises two burners, two regenerators, a reversing valve and reversing logic. While one of the burners fires using cold air fed to the base of its regenerator, exhaust gas is drawn through the other burner and down into its associated regenerator to preheat the packing, then discharged to atmosphere. When |