CFB煤燃烧/热解双反应器中热解室对立管内气固流动特性的影响

考察了循环流化床煤燃烧/热解双反应器系统中热解室的存在对立管内的压力分布及气固流动状况的影响。提升管的内径100 mm、高6 m，立管的内径44 mm、高3 m，热解室的截面积200 mm×200 mm、高770 mm。结果表明，随着提升管内表观气速Ur的增加，有无热解室立管内均为负压差流动，负压差梯度随着Ur的增加而减小。有热解室时，热解室内要保持一定的料位高度，整个立管内固体颗粒的流动为负压差移动床流动；没有热解室时，立管内为稀相流动和移动床流动同时存在，立管内平衡料柱高度随Ur的增加而升高。随着循环量Gs的增加，两种类型的立管内负压差梯度均随之增大，也存在着流动形态的差别。循环量Gs的增加会引起立管内平衡料柱高度的降低。立管内气固相对滑移速度也随着循环量Gs的增加而增大。

Effects of pyrolysis chamber on gas/solid flow characteristics of the standpipe in a CFB combined with coal pyrolysis reactor system

Effects of the pyrolysis chamber on the pressure distribution and the behavior of gas/solid flow in the standpipe of a CFB combined with coal pyrolysis reactor were studied. The riser column was 0.1m in diameter, 6m in height. And the standpipe was 0.044m in diameter, 3m in height. The rectangle pyrolysis chamber with cone-shaped distributing plates laid between the cyclone dipleg and the standpipe. The across section and the height of the chamber are 200mm×200mm and 0.77m respectively. The experiments showed that with the increase of the superficial gas velocity in the riser, Ur , the flow pattern in the standpipe was negative pressure difference flow whether the pyrolysis chamber was set up in the standpipe or not. And the negative pressure gradient decreased with Ur increasing. Solids in pyrolysis chamber must maintain a certain height, the flow pattern in the whole standpipe was negative pressure difference moving bed. If without pyrolysis chamber, the lean phase flow and the moving bed flow co-existed in the standpipe. And with the increase of Ur ,the equilibrium height of the solid in the standpipe was heightened. With circulating rate Gs increasing,the negative pressure gradient in the two type standpipes increased also. Without pyrolysis chamber, the increase of the circulating rate Gs would cause the equilibrium height of the solid in the standpipe declined. With Gs increasing the slip velocity in the standpipe was also increased.