循环流化床煤燃烧／热解双反应器系统稳定性分析

Stability analysis of system of circulation fluidized bed combined with a coal pyrolysis reactor

为了考察循环流化床煤燃烧/热解双反应器系统的稳定性,在冷态实验装置上以电厂锅炉灰为实验物料,其中提升管的内径为100 mm,高为6.7 m,与热解室相连立管的内径为44 mm,高3 m,热解室的截面积为200 mm×200 mm,高770 mm。分别考察了影响系统稳定运行的主要因素,并对系统中存在的几对平衡关系进行了分析。结果表明,旋风料腿内的固体料位高度、热解室内的料位高度以及热解室内的压力等是影响系统稳定运行的关键因素,尤其是热解室内压力的增加有可能使立管内料封破坏,最终导致系统瘫痪。而提升管与热解室立管之间压力的平衡以及提升管与旋风分离器料腿之间压力的平衡等在操作过程中必须保持稳定,否则也会发生窜气、架料、旋风分离器效率下降等现象,影响系统稳定运行。

In order to study the stability of circulation fluidized bed （CFB） combined with a coal pyrolysis reactor, the ash of power plant was used as experimental material in the cold mold reactor system. The riser colunm was 100 mm in inside diameter, 6.7 m in height. And the standpipe attached to the pyrolysis chamber was 44 mm in inside diameter, 3 m in height. The rectangle pyrolysis chamber with cone-shaped distributing plates was arrmged between the cyclone dipleg and the standpipe, which has a cross section of 200 mm × 200 mm and a height of 770 mm. The main factors affecting the system running were studied respectively. The several balance relations in the system were analyzed. The results show that solid height in cyclone dipleg, solid height and pressure in the pyrolysis chamber are important factors for the system nmning stably. Solid seal in the standpipe would be destroyed with increasing pressure in the pyrolysis chamber, which results in the system broken. The pressure between the riser and the standpipe and between the riser and the cyclone dipleg should be kept in balance, or else the gas has back flow, bridging in dipleg and falling of the cyclone efficiency would happen, and the stability of the system operation is affected.