酸洗脱矿对胜利褐煤热解过程中N迁移转化的影响  

Influence of demineralization using acid wash on N migration and transformation during pyrolysis of Shengli brown coal

作　　者：王永刚[1] 郑盼盼[1] 杨萨莎[1] 张书[1] 白艳萍 贾晓路 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083

出　　处：《燃料化学学报》2014年第5期519-526,共8页Journal of Fuel Chemistry and Technology

基　　金：国家科技支撑计划(2012BAA04B02)

摘　　要：在石英管流化床反应器中对胜利褐煤进行快速热解实验,考察了773-1 173 K下酸洗脱矿对胜利褐煤热解过程中N迁移转化规律的影响。通过比较原煤和酸洗后煤中N的不同逸出规律可以得出,影响酸洗前后胜利褐煤热解过程中N迁移转化规律的主要是碱金属Na及碱土金属Ca;热解过程中,煤中的Na和Ca促使煤中的N向NH3转化并有效抑制了HCN的生成,金属离子的存在对催化焦油N转化为NH3的作用较为明显;原煤中的碱金属和碱土金属的赋存使半焦裂解反应加剧,降低了固体半焦的产率,半焦N的产率也随之减少;与原煤相比,酸洗煤热解半焦中的吡啶型N（N-6）含量较多,而吡咯型N（N-5）和季N（N-Q）相对较少。This paper is to examine effects of inherent minerals in coal on N migration and transformation during the fast pyrolysis of Shengli brown coal at the temperatures of 773 ~ 1 173 K in a bench-scale fluidized-bed quartz reactor. Based on the comparison between rawcoal and acid-washed coal,we can find that the alkali Na and alkaline Ca were the key reasons for the difference in N evolutions from rawcoal and demineralized coal during the pyrolysis. The Na and Ca could efficiently facilitate the formation of NH3and inhibit the production of HCN. The metallic species had obvious catalytic effects for the conversion from tar-N to NH3. Meantime,the existence of alkali and alkaline metals has enhanced the cracking reactions of coal char,thus reducing the yields of char and char-N. In addition,the relative amount of pyridinic（N-6） in demineralized coal char was higher than that in rawcoal,while less quternary type nitrogen（N-Q） and pyrrolic nitrogen（N-5） were found in the demineralized coal char.

关 键 词：褐煤 热解 氮 碱金属 碱土金属 

分 类 号：TQ541[化学工程—煤化学工程]