内在矿物对高灰褐煤热解焦收率及特性的影响  

Impact of inherent minerals on the yield and properties of char from pyrolysis of the lignite with high ash content

作　　者：李昌伦[1] 王永刚[1] 林雄超[1] 杨远平[1] 田震[1] 武欣[1] LI Changlun WANG Yonggang LIN Xiongchao YANG Yuanping TIAN Zhen WU Xin(School of Chemical and Environmental Engineering, China University of Mining and Technology （Beijing） , Beijing 100083, China)

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：《煤炭学报》2017年第8期2157-2163,共7页Journal of China Coal Society

基　　金："十二五"国家科技支撑计划重点资助项目(2012BAA04B02);国家自然科学基金资助项目(21406261)

摘　　要：利用分选、酸洗和添加矿物的方法制备出不同灰含量和矿物成分的褐煤煤样;使用沉降管反应器(DTR)和热重分析仪(TGA)研究内在矿物在800~1 200℃对褐煤热解的影响。结果表明,内在矿物可以降低褐煤的热解反应活性,增加低温(800)热解焦收率;碱金属和碱土金属(AAEM)是起主要作用的矿物成分。在高温条件下(≥1 000℃),内在矿物可通过催化原位水蒸气气化反应降低焦收率。焦收率的减少量正相关于煤样的灰分含量和内水含量,以及碱性金属总量。Raman光谱分析表明,内在矿物有延缓半焦微晶结构有序化和抑制交联键断裂的作用。内在矿物可促进半焦孔结构的形成,增大半焦的比表面积;钙为起主要作用的矿物成分。随热解温度的上升,过多的矿物会抑制半焦孔结构的进一步扩展。In order to investigate the impact of inherent minerals on pyrolysis for lignite with high ash content, some py- rolysis experiments were conducted in Drop Tube Reactor and Thermogravimetrie analyzer at 800-1 200 ℃. Lignite samples containing different ash and mineral compositions were prepared by separation, acid demineralization and min- eral addition. Results show that the inherent minerals could reduce the pyrolysis reactivity of lignite and increase the char yield at low temperature （800 ~C ） ;AAEM played a major role. While at high temperature （ ~〉 1 000 ~C ）, the in- herent minerals reduced the char yield by in-situ catalyzed steam-gasification. The reduction in char yield was directly related to the ash and internal water content of coal samples, as well as the total amount of basic metals. Raman analy- sis showed the inherent minerals can disorder the microcrystalline structure of char and inhibit the fracture of cross- linking bonds. The surface of char was increased by Ca as the main role of inherent mineral composition. With the py- rolysis temperature increasing, the excessive mineral will inhibit the further expansion of porosity for chars.

关 键 词：褐煤 内在矿物 热解 焦收率 微观结构 

分 类 号：TQ530.2[化学工程—煤化学工程]