生物质空气/水蒸汽气化的综合计算法模型

A comprehensive calculation model of biomass gasification used air/steam

建立生物质气化模型的目的在于确定用某种燃料为气化原料时所生成煤气的组成、热值、煤气产率、气化剂的消耗量与热效率等,并为选用设计气化系统及设备提供依据。根据生物质气化炉实测数据对煤的综合计算法模型进行了修正。主要调整了干馏段生物质气的产率及气化段的碳氮比特征值n。其中,干馏产物中CO2的产率设定为氧含量的30%,焦油的产率设定为挥发分的10%;气化段的碳氮比特征值n对应着不同的鼓风量,风量大时n值得取值小,反之亦然,在实际气化炉中过量空气系数在0.2～0.4之间,对应的n值的取值由原来的0.6变为0.3～0.6之间;此外,根据固定碳量给定了水蒸汽的喷入量。建模结果还与其它学者的实验数据进行了对比,模拟结果符合良好,在一定程度上证明了模型的有效性和可靠性。

Biomass gasification model aims to determine the syngas composition,heating value,gas yield,heating value,gasification agent consumption and thermal efficiency to a specific gasification fuel,and the model can provide the basis to design for the gasification system and equipment selection.Based on the actual operation data of biomass gasifier,the comprehensive calculation model of biomass gasification had been amended to coal gasification.The syngas composition in retorting stage and the ratio of carbon to nitrogen were adjusted mainly.The CO2 production rate in retorting stage was set to 30% oxygen content of fuel;and the tar yield was set to 10% volatile matter of fuel.The ratio of carbon to nitrogen n corresponds to a different blast volume,the blast volume decreases with the ratio of carbon to nitrogen n increases,and vice versa.The equivalence ratio of agent is 0.2 to 0.4 in the actual gasifier,so the ratio of carbon to nitrogen n is 0.3 to 0.6.In addition,the amount of injected steam was set on fixed carbon of fuel.The calculated data was compared with the actual experimental results and other scholars of the experimental data,which shows a largely satisfactory agreement and p roves the effectiveness and reliability of this model.