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Show INDUSTRIAL APPLICATIONS OF THE PYROCORE BURNER Wayne V. Krill, Rick Pam Alzeta Corporation Santa Clara, California, USA ABSTRACT The pyrocore burner has undergone development to extend its use from residential sizes up to industrial applications. Initially developed under sponsorship of the U.S. Environmental Protection Agency and subsequently more extensively by the Gas Research Institute, the problems of constructing and operating a large radiant surface burner were overcome. Large, segmented cylindrical burners were first developed for firetube steam boilers and later extended to more general immersion tube applications. The extended cylindrical surface provides a very uniform, highly radiant heat flux to the tube wall. This feature allows process efficiencies to be enhanced by avoiding high temperature zones in heating equipment. The burner can be made in a variety of lengths and diameters and other configurations to match heating needs. The low temperature combustion process produces very low nitrogen oxide (NOx ) emissions -- important in regions of regulated air quality. In addition to steam raising in firetube boilers, the pyrocore immersion tube burner is finding applications in heating fluids that are sensitive to degradation at high temperatures or excessive local heat fluxes. Examples are: • Asphalt tank and line heaters • Glycol heaters for natural gas dehydration • Heat transfer fluid and oil heaters 267 o Crude oil treating o Salt bath heaters In boiler applications, a 1 to 2 percentage point efficiency improvement is common with reduced NOx emissions and the elimination of flame noise. In petrochemical processes, higher heating rates to the fluid can also increase production rates from an existing piece of equipment. Data show enhanced life of the heated fluid and the heater firing tube. IN EARLY DEVELOPMENT WORK, the Pyrocore radiant burner showed promise for use in industrial combustion systems. To achieve these applications, design, fabrication, and demonstration were required to prove the technology at sizes beyond those of its existing uses. This paper describes the development history of the burner and the industrial uses that are now becoming of importance. DESCRIPTION OF THE PYROCORE BURNER The Pyrocore gas burner is a premixed radiant surface infrared burner. A radiant burner is distinguished from a conventional burner by its lack of a suspended flame and its incandescent surface. This surface transfers much of the burner's heat input to an adjacent heat sink by thermal radiation. The burner can be used wherever this highly radiant heat transfer to a defined surface area is desired. The active pyrocore surface is a ceramic composition which is formed |