内嵌逆流柱型风帽防漏特性的实验研究

Experimental Study of the Leakage Prevention Characteristics of a Built-in Counterflow Cylindrically-shaped Air Button

对用于200 MW循环流化床锅炉炉膛布风板上的内嵌逆流柱型风帽,用水模拟床料,人为分割风室,造成一个不平衡的风室压力,使得特定风帽发生漏水。当流化风量分别为2 640、3 120、3 600以及4 080 m3/h,水位分别为63、163和263 mm时,研究风帽漏水时风室的压力特性。在风帽发生漏水时,发生漏水的风室压力急剧波动,正常风室的压力与发生漏水时风室的最小压力之间存在临界关系;临界压差随风帽阻力的增大而增大;在相同的流化风量下,临界压差随床层压力的增大而减小。通过这些实验,对循环流化床锅炉炉膛布风板的风帽漏渣机理进行了分析,为提高风帽的防漏性能提供参考。

For built-in counterflow cylindrically-shaped air buttons destined for the furnace air distributor of a 200 MW circulating fluidized bed boiler,water was used to simulate the bed material and the air chamber was artificially divided,forming a non-equilibrium pressure distribution in the air chamber and leading to a water leakage from the special-purpose air buttons.When the fluidized air quantities were 2640,3120,3600 and 4080 m3/h respectively and the water levels were 63,163 and 263 mm respectively,the pressure characteristics of the air chamber when a water leakage came from the air buttons were studied.When a water leakage from the air buttons occurs,the air chamber with a water leakage will drastically fluctuate.A critical relationship exists between the normal pressure in the air chamber and its minimum pressure during the water leakage.The critical pressure difference will increase with an increase of the drag in the air buttons.At a same fluidized air quantity,the critical pressure difference will decrease with an increase of the bed pressure.Through the tests,the mechanism controlling the slag leakage from the air buttons on the air distributor of the circulating fluidized bed boiler was analyzed,thus providing reference for improving the leakage prevention performance of air buttons.