气化条件下混煤灰熔融特性及矿物质演变规律  

Ash Fusion Characteristics and Mineral Evolvement of Blended Ash Under Gasification Condition

作　　者：乌晓江[1,2] 张忠孝[1] 周托[3] 陈玉爽[3] 陈国艳[3] 陆成[3] 黄凤豹[3] 

机构地区：[1]上海交通大学机械与动力工程学院,上海200240 [2]上海电气电站集团,上海201100 [3]上海理工大学能源与动力工程学院,上海200093

出　　处：《燃烧科学与技术》2010年第6期508-514,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(50906055);中国博士后科学基金资助项目(20090450571)

摘　　要：通过实验研究了高温气化条件下混煤灰的熔融特性及矿物质演变规律.结果表明,气化条件下混煤灰熔融温度的变化规律并不与配煤比例成线性关系,而与相应三元相图的液相线温度具有良好的相似性;随着低灰熔点煤灰的加入,混煤灰在三元相图上的位置逐渐由莫来石结晶区向钙长石结晶区移动,并在二元共晶线或三元共晶点附近熔融温度的变化最为显著,且低于周围位置的熔融温度;由于低灰熔点煤灰中含有较多的硬石膏、辉石、长石等矿物,高温气化条件下能分解成CaO、FeO等助熔矿物,这些助熔矿物能够与高灰熔点煤灰中的莫来石、石英等发生反应生成钙长石、铁橄榄石等低熔融矿物,从而降低了高灰熔点煤灰的熔融温度.The ash fusion characteristics and mineral evolvement of blended coal ash under gasification condition at high temperature were studied.The results show that the trends of the ash fusion temperature（AFT） of blended coal ashes is not in linear relationship with the proportions of blended coal ash,but its change is similar to that of liquid temperature from ternary phase diagram systems.With the increase of mass fraction of low AFT ash,the bulk chemical composition of blended coal ash moves from the mullite region towards the anorthite region in ternary phase system.Furthermore,the AFTs of blended coal ashes whose main chemical compositions are located near the boundaries between mineral regions or triple points,change more evidently and are lower than those far away from the boundaries.Anhydrite,augite and feldspar in low AFT coal ash,will discompose into CaO and FeO fluxing minerals at high temperature under gasification condition,which will react with mullite and quartz,in high AFT coal ash to produce such low melting point minerals as anorthite and fayalite,finally decreasing the AFT of high AFT coal ash.

关 键 词：混煤灰 灰熔融特性 矿物质 煤气化 

分 类 号：TQ531[化学工程—煤化学工程]