加压热解气氛对碳酸钾催化煤热解过程中硫迁移的影响  

Effects of different atmospheres on sulfur transformation during K_2CO_3 catalytic pressurized pyrolysis of coal

作　　者：刘方刚[1,2] 张永[1,2] 曲旋[1] 张荣[1] 毕继诚[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001 [2]中国科学院大学,北京100049

出　　处：《燃料化学学报》2016年第11期1287-1296,共10页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(21576275);国家重点基础研究发展规划(973计划;2011CB201305)资助~~

摘　　要：在加压热解装置上,考察了碳酸钾及热解气氛对煤热解过程中硫分布及其形态的影响。结果表明,碳酸钾通过捕获H_2S增加了半焦硫含量,同时可将煤焦表面活化,导致煤中有机质与黄铁矿分解产生的活泼硫结合形成新的有机硫。氢气能促进煤中硫的脱除,但是碳酸钾存在下热解释放的硫一部分以K_2S的形式固定于半焦中。水蒸气可显著促进煤中黄铁矿的分解,同时可与煤焦中的K_2S反应,降低半焦中的硫含量。两段床催化气化炉中,碳酸钾催化剂经热解后不影响其对煤焦的催化性能。The effects of K_2CO_3 and atmospheres on sulfur distribution and forms during pressurized coal pyrolysis were investigated in a lab-scale reactor. The results show that K_2CO_3 increases the sulfur remained in char by capturing H_2S during coal pyrolysis. The surface of the coal char is activated in the presence of K_2CO_3,and then the nascent sulfur releasing from the pyrite is captured by the organic matrix in coal to form new organic sulfur. Hydrogen shows positive effects on removal of pyrite and organic sulfur,and the released H_2S is partly fixed in char in the form of K_2S when K_2CO_3 was added. The decomposition of pyrite is enhanced in H_2O atmosphere. Meanwhile,K_2S in char can not exist due to effect of water vapour,so the sulfur remained in char is notably reduced. The catalytic property of K_2CO_3 on char gasification is not changed after pyrolysis in twostage catalytic coal gasifier.

关 键 词：催化加压热解 碳酸钾 硫迁移 

分 类 号：TQ54[化学工程—煤化学工程]