CuFe_(2)O_(4)氧载体与小麦秆-煤化学链共气化研究

Research on Chemical Looping Co-gasification of Wheat Straw-Coal with CuFe_(2)O_(4)Oxygen Carrier

以小麦秆与印尼褐煤为原料,制备具有尖晶石结构的CuFe_(2)O_(4)复合氧载体,在自制多功能反应器上,系统研究了CuFe_(2)O_(4)氧载体反应活性及小麦秆和印尼褐煤化学链共气化特性,重点关注小麦秆和煤不同掺混比、气化温度、氧载体过量系数和水蒸气输入量这4个关键运行参数的影响。结果表明:CuFe_(2)O_(4)复合氧载体中Cu-Fe的协同作用有助于晶格氧的有效传递和反应活性的提升,而小麦秆和印尼褐煤化学链共气化时碳转化率及冷煤气效率比单一燃料的大,促进了高品质合成气的形成;小麦秆和褐煤在与CuFe_(2)O_(4)化学链气化过程中的最优运行参数为共气化温度950℃、氧载体过量系数0.2、水蒸气通入体积流量0.125 mL/min、小麦秆-印尼褐煤掺混质量比1∶1,在此最优条件下,合成气产量高达1.262 m^(3)/kg,H_(2)与CO体积比为1.69,碳转化率为89.7%,合成气选择性为63.2%。

Wheat straw and Indonesian lignite were used as the raw material,the combined oxygen carrier(OC)CuFe_(2)O_(4)with spinel structure was prepared.The reactivity of the prepared CuFe_(2)O_(4)combined OC and the synergistic behavior of the co-gasification of wheat straw-Indonesian lignite were studied on the tailored multifunctional reactor with four operation influencing factors being concentrated,including the mixing mass ratio of wheat straw to the lignite,gasification temperature,CuFe_(2)O_(4)OC excess coefficient and steam input amount.Results show that during chemical looping gasification(CLG)of wheat straw-lignite with CuFe_(2)O_(4)OC,Cu-Fe ingredients involved in CuFe_(2)O_(4)promote oxygen transfer and elevate its reactivity.Meanwhile,the carbon conversion and cold gas efficiency(CGE)for the co-gasification of wheat straw-lignite are much higher than those of the single fuel,thus desirable high quality of the gasification products can be produced.Furthermore,the optimized operational factors are determined,including gasification temperature at 950℃,OC excess number around 0.2,steam input volumetric flow rate with 0.125 mL/min and the mixed mass ratio of the wheat straw to lignite at 1∶1.Thereby,the syngas yield peak reaches 1.262 m^(3)/kg with H_(2)/CO ratio of 1.69,the carbon conversion of 89.7%,and the syngas selectivity of 63.2%.