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Show Because of the very competitive market place, fuel fired boilers are designed using a maximum volumetric heat release. The resulting radiation section volume provides insufficient residence time for the hazardous waste combustion reactions to proceed to a degree corresponding to a DRE of 99.99%. An option, which may or may not be an option depending on steam requirements, is to fire the boiler at less than design rate which, for seme wastes, in some cases may be less than half of design rate. Boilers fired by a hazardous waste other than that specified for their design, fuel fired boilers operating at more than 50% of their design rate and partially fired by hazardous wastes; and the intent of incinerator regulations prompted the development of the Hazardous Waste Steam Generator concept which is the subject of this paper. This paper is divided into three sections. The first section describes the results of a study to up-grade the combustion performance of a fuel fired packaged boiler partially fired by hazardous waste. The second section briefly describes existing packaged boilers designed to fire hazardous wastes. The third section describes the Hazardous Waste Steam Generation Concept, its inherent ability to achieve a DRE of 99.99%, the relative ease of upgrading an existing boiler to produce this process, and current development activities. FIRED BOILER UPGRADE STUDY Hazardous waste incinerator regulations currently in place have caused a chemical company to be concerned about the capability of their packaged boilers to destroy their hazardous plant wastes. Their goal was to fire only hazardous wastes, produce about the same amount of steam and achieve the destruction prescribed by incinerator regulations. The boilers under evaluation were the packaged D type designed to produce 35,000 lb/hr of saturated steam at 250 psig. Each boiler was fired with a combination natural gas/#2 fuel oil burner capable of firing 50 MM Btu/hr. The design volumetric heat release was determined to be approximately 81,600 Btu/hr-ft3. None of the boilers was fitted with an econcmizer. 5.8.3 |