HYDRODYNAMICS OF CIRCULATING FLUIDIZED BED WITH SECONDARY AIR INJECTION CENTRALLY LOCATED: AN EXPERIMENTAL STUDY
IntroductionIn a circulating fluidized bed combustor, secondary air (SA) injections or the so-called air staging is obtained by splitting the combustion air into primary air (PA) and secondary air. The SA is usually laterally injected into the combustor from the nozzles on the wall along the riser. The main motivation of the SA injection is its effectiveness in controlling the nitrogen oxides (NOx) formation1 and combustion process2. With the capacity of CFB boilers increasing, the gas-solids mixing becomes a problem when the boilers size increasing. Xiao3 and Ljungdahl 4pointed out that the SA can not penetrate sufficiently deeper in the furnace. To solve this problem, higher air velocity is suggested. And pant-leg type CFB boiler has been utilized successfully in several 300 Mwe CFBB power units. But the problem of bed material unbalance between the two legs in the furnace is founded during the operation. The bed materials can not flow freely between the two legs is one important reason for that phenomenon. For improving the gas-fuel mixing in large industrial circulating fluidized bed (CFB) boilers, a lateral secondary air (SA) injection mode with air nozzles centrally located in the riser is presented in this paper. And the influence of centrally located secondary air injection on the hydrodynamics of circulating fluidized beds was studied in a cold model CFB riser.
Wang Zhengyang Sun Shaozeng Deng Qigang Wang Xiaoyu Wu Shaohua Qin Yukun
Combustion Engineering Research Institute, Harbin Institute of Technology, Harbin, 150001, China
国际会议
The 7th China-Korea Workshop on Clean Energy Technology(第七届中韩清洁能源技术研讨会)
太原
英文
47-48
2008-06-25（万方平台首次上网日期，不代表论文的发表时间）