循环流化床(CFB)煤/焦气化反应的研究 Ⅰ.操作气速、固体循环速率对循环流化床气化反应的影响

STUDY ON GASIFICATION REACTION OF COAL AND CHAR IN CIRCULATING FLUIDIZED BED (CFB) Ⅰ EFFECT OF OPERATING GAS VELOCITY AND SOLID CIRCULATING RATE TO GASIFICATION REACTION IN CFB

报道了山西西山焦煤飞灰，在小型循环流化床气化反应器上，以二氧化碳为气化介质，在不同操作条件下（气速、固体循环速率）的气化反应。研究结果表明，ＣＯ出口浓度及碳转化率随着ＣＦＢ操作气速减小、固体颗粒循环速率的增加而增加。即在ＣＦＢ床中，提高气体、固体停留时间（床内固体颗粒浓度）有利于ＣＦＢ气化的进行。ＣＯ浓度及碳转化率沿床高的变化趋势与床内颗粒浓度分布一致。

In this paper, a study on the gasification reaction of fly ash of Xishan coking coal in an experimental circulating fluidized bed reactor is reported The CFB gasifier heated by electrical heaters mainly consists of a riser (48mm id ×3560mm), a solidsgas separator system and a 68mm id recirculation column The fly ash reacted with CO 2 at different conditionsgas velocity and solid circulating rate The test results show that the CO concentration, carbon conversion and gasification efficiency increase when gas velocity decrease under same fuel feed rate It is mainly because of the increasing of solids holdup In addition, the reactant gas residence time increases from 2 82 seconds to 3 73 seconds when gas velocity decrease from 1 2 to 0 95m/s At same condition, the solids holdup in bed increases with the increasing of solid circulating rate Therefore, more solid particles take part in the gasification reaction, and then CO concentration and carbon conversion increase The axial CO concentration profile has correspondent relationship with that of the axial solid particle concentration