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Show APPLICATIONS The reGen Regenerative Burner has been applied to a wide spectrum of batch and continuous direct fired furnaces in the steel, non-ferrous, and glass industries. The first application is a very hot, dirty and corrosive environment. It is the one which we used as our initial test-bed for operation with this class of exhaust gas, and has been operating for over three years without problems. -APPLICATION- 1400°C OPEN POT GLASS MELTING FURNACE TRANSLUCENT GLASS LTD., WAKEFIELD, U.K. DATE OF INSTALLATION - February 1983. EQUIPMENT - One 1 GJ/h (1 million BTU/hr) gas fired unit comprising two burners,two regenerators and associated controls. DESCRIPTION - The furnace is a single pot soda lime glass melting unit originally fitted with a ceramic recuperator using the Teisen design hexagonal fireclay jointed tiles. In that the pots used are open topped (like a crucible) the furnace is exactly similar to a day tank when effects of volatiles and carryover on its firing system and refractory superstructure are considered. OPE RAT ION - The furnace is used for production of I ighting ware from hand gathered gobs. The pot is charged with batch and cu Ilett by shovel through the hand gathering port. After charging at the end of the working day with the furnace at about 1200°C (2200°F), the temperature is ra ised over 6 hou rs to 1400°C (2550° F) and held there for 6 hours for melting. The temperature is then reduced to 1175°C (2150°F) over 3 hours and operated between 1175°C (2150°F) and 1200°C (2200°F) for the 8 hour gathering period. OBSERVATIONS - While no problems were anticipated with the temperature or corrosive nature of the waste gases in this application, plugging of the regenerators by condensed volatiles and/or batch carryover from the chargi ng operation was an unknown factor. I n the 81 event it has been shown that whilst plugging does of course occur, its effect on thermal performance is not severe up to the point at which the system becomes unable to operate because of inability of the fans installed to overcome the increased resi stance of the regenerators. Once each month the user cleans out the condensed volati les from the regenerators without shutting the system down by the following quick and si mpl e process. The fi ring rate is set to low fire, the reversing system fixed in one position and the gathering port cover removed. The exhaust va I ve on the non - fir i·ng regenerator is then closed, causing the firing burner to exhaust out of the gathering hole. The packing is then drained out of the non-firing regenerator, allowed to cool and then placed in a concrete mixer, the rotation of which causes spall i ng of the friable condeosed products from the packing elements. The contents of the mixer are dumped into a sieve to separate the packing from the fou ling and the pack i ng poured back into the regenerator. The reversing valve is then operated once and the process repeated for the other regenerator, the whole process taking approximately 50 minutes for the two regenerators. PERFORMANCE - As noted above, the furnace was fitted with a rudimentary ceramic recuperator pr i or to the i nsta II at ion of the reGen un it. It had been shut down for rebui Id prior to the decision to use the Regenerative Burner and thus no concerted effort had been made to collect data on fuel usage to support subsequent economic evaluation. In actual fact the high temperature, corrosion and foul ing were the important points for evaluation for us, the energy saving aspects being capable of estimation by simple temperature measurement and heat balance. The thermal analysis showed the regenerators to be operating in the 90% effective region with overall combustion efficiency of 73 to 77%. Typical waste gas temperatures from the 1400°C (2550°F) furnace are around 175°C (350°F) at the bottom of the regenerator. The customer. has reported a fuel saving of about 20% over the previous reported recuperative performance, based on long term analysis of utility billings. FEATURES - The Regenerative Burner has proved itself capable of resisting the corrosion and fouling from a 1400°C (2550°F) soda lime glass furnace waste gas stream. I t has proved that it can be easily and quickly cleaned of the fouling that will occur when handling gas streams containing volatiles. It has proved that it can withstand these conditions for long periods with only minimal maintenance. It has demonstrated that it will maintain its high heat recovery effectiveness under dirty gas conditions. I t has demonstrated that the exhaust gas from a 1400°C (2550°F) process really can be lead away from the furnace in black mild steel gas pipe with screwed fittings. I t has proved that the basic control ph i losop'hy developed in the laboratory to ensure balance of regenerators in operation is sound and practical •. |