| The regenerative heat exchange technology is a highly efficient technology for heat recovery of flue gas. The fuel can be saved to the greatest extent, and the pollutant emissions can be reduced. High temperature combustion technology is developed on the basis of that and is becoming more and more widely used. Not only the combustion efficiency of fuel can be improved, but also a reasonable way to use low-calorific value fuel is found. It meets the requirement of China’s industrial strategy for sustainable development. But frequent commutation is needed for conventional regenerative heat exchanger, which causes the fluctuation of furnace temperature and pressure, discontinuity of combustion while reversing and reduction of heating quality. The advantage of this technology is greatly reduced. Only to realize the continuous and stable high temperature air combustion, the advantages of high temperature air combustion can be reflected.In view of the problems of regenerative heat exchanger existing, the rotary regenerative heat exchanger has been designed and its heat transfer and resistance characteristics has been researched. Experiments and theories are combined to study the effects of operating parameters on thermal performance in the research. It’s concentrated on the resistance and heat transfer characteristics of ceramic ball and ceramic honeycomb, heat and mechanical design of rotary regenerative heat exchanger. The main research contents are as follows:(1) From the cold experiments, the influence of packed bed height, ceramic ball diameter, gas velocity on resistance loss is known. Two coefficients K1, K2of Ergun equation are amended:261,0.52. Through hot state test, the influence of ceramic ball diameter and packed bed height on heat transfer characteristics of thermal efficiency is known.(2) The resistance and heat transfer performance of the square, regular hexagon, round honeycomb are analyzed. The honeycomb pressure loss is calculated theoretically as:(3) Reference from thermal design for counterattack runoff heat exchanger in thermal design and the characteristics of the ceramic heat exchanger, the thermal design method of rotary regenerative heat exchanger has been proposed. Heat exchangers of ceramic honeycomb and ceramic ball are calculated respectively according to different flue gas conditions. The temperature distribution of a ceramic honeycomb heat exchanger is calculated theoretically and the laws are got. The influence of flow rate and rotating period to thermal performance is calculated and analyzed.(4) A reasonable and feasible mechanical design method has been given to solve the sealing, supporting and driving problems of rotary regenerative heat exchanger, which guarantees the reliable operation of the rotary regenerative heat exchanger.In conclusion, there is a theoretical basis for the method of designing ceramic honeycomb regenerators and the method is simple, which provides reference for rotary regenerative heat exchanger design. Pictures35, Tabless10, Referemces71. |
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