气力输送状态下利用高活性吸收剂的循环流化床烟气脱硫模型

A Model of Desufurization with Highly Active Absorbents Under Pneumatic Conveying Conditions of Circulating Fluidized Beds

利用以工业石灰、粉煤灰和添加剂制备的高活性吸收剂在循环流化床上进行了脱硫实验。通过对床内流场和温度场的分析,建立了气力输送状态下循环流化床物理模型。在此基础上,针对床内喷水增湿活化脱硫时吸收剂的三种不同物态:新鲜干燥颗粒、干燥再循环颗粒、含水颗粒,分别建立了与之对应的表面覆盖模型、气固反应模型、浆滴脱硫模型,并总结出气力输送状态下利用高活性吸收剂的循环流化床总脱硫模型。同时通过实验数据对模型进行了校核,校核结果误差在5.5%以内,较以往模型具有更高的精度。

Experiments of desulfurization with highly active absorbents, consisting of industrial lime, pulverized coal ash and additives, were carried out in a circulating fluidized bed （CFB）, and, after having analyzed the flow and the temperature field in the bed, a physical model of the circulating fluidized bed under pneumatic conveying conditions has been established. Herewith, focusing on the three different states of the absorbents, that appear when spraying water into the bed for enhancing desulfurization activity, i.e. fresh dry particles, dry recirculating particles and slurry particles, a surface covered model, a gas-solid reaction model and a slurry droplet desulfurization model were respectively set up. A circulating fluidized bed＇s general model of desulfurization with highly activated absorbents under pneumatic conveying conditions was further obtained by summarization. A check with experimental data exhibited errors less than 5.5 %, a precision higher than can be obtained with earlier models. Figs 8, tablel and refs 18.