循环流化床单床与双床煤气化特性试验研究

Experimental Research on Coal Gasification Characteristics in Single and Dual Circulating Fluidized Beds

在循环流化床单床与循环流化床双床试验台上,对神华煤在不同空气煤比下的气化特性进行了试验研究。在同等试验条件下,单床气化时碳转化率随空气煤比的增加呈先增后减趋势,而双床气化呈单调上升趋势,单床与双床气化时,碳的总转化率最高均可以达到97%左右。循环流化床单床气化的化学热损失是双床气化化学热损失的2.3倍,双床煤气化系统的热效率高于单床煤气化系统,双床气化时煤气有效成分(CO、H2与CH4之和)最低体积浓度是单床气化时有效成分最高体积浓度的1.6倍,双床气化时的最低煤气热值为单床气化时最高煤气热值的2.7倍,循环流化床双床煤气化是无纯氧条件下获取中高热值煤气有效的途径之一。

Gasification characteristics of Shenhua coal were experimentally studied in the single and dual circulating fluidized beds test rigs under the different ratios of air and coal. Under the same experimental condition, the carbon conversion rate took on the trend of firstly increasing then decreasing with the ratio of air and coal increasing in the single circulating fiuidized bed gasification, but the conversion rate only linearly increased in the dual circulating fluidized beds gasification, and the highest total carbon conversion rate may attain about 97.0% in the single and dual circulating fluidized beds. The chemical hot loss of the single circulating fluidized bed was 2.3 times that of the dual circulating fluidized beds, and the thermal efficiency of the dual circulating fluidized beds was higher than that of the single circulating fluidized bed. Moreover, the lowest volume concentration of gas effective components （total amount of CO, HE and CH4） during the dual circulating fluidized beds gasification was 1.6 times the highest volume concentration of gas effective components during the single circulating fluidized bed gasification, the lowest gas caloric value in the dual circulating fluidized beds was 2.7 times the highest gas caloric value in the single circulating fluidized bed, so the coal gasification in the dual circulating fluidized beds provides a new effective approach to gain the middle or high gas caloric value without pure oxygen.