高砷无烟煤低负荷燃烧过程中砷的释放特性及灰中砷形态分布规律  

Study of Release Characteristics of Arsenic and Distribution Pattern of Arsenic Species in Ash During Low-load Combustion of High-arsenic Anthracite Coal

作　　者：袁潇 邢佳颖 王震[1] 王春波[1] YUAN Xiao;XING Jiaying;WANG Zhen;WANG Chunbo(Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology,Department of Energy Power&Mechanical Engineering,North China Electric Power University,Baoding 071003,Hebei Province,China)

机构地区：[1]华北电力大学动力工程系,河北省低碳高效发电技术重点实验室,河北保定071003

出　　处：《动力工程学报》2024年第7期1129-1136,共8页Journal of Chinese Society of Power Engineering

基　　金：国家重点研发计划资助项目(2020YFB0606301);国家自然科学基金资助项目(51976059)。

摘　　要：选取高砷无烟煤,采用管式炉研究了低负荷燃煤工况下砷的释放及灰中砷形态的变化规律。结果表明:800~900℃区间内,随着温度的升高煤中砷的释放速率出现明显峰值,灰中As^(3+)占比呈上升趋势;灰中弱吸附态砷在800~900℃区间逐步升高,在900℃时As^(3+)占比达到最大值;1000~1200℃区间内,灰中弱吸附态砷氧化分解,砷酸盐占比增加,促使As^(3+)向As^(5+)转变,As^(3+)占比逐渐降低;O_(2)体积分数的升高促进了灰中As^(3+)的氧化过程;此外,随着炉内煤粉停留时间的增加,煤中砷的释放速率与灰中As^(3+)占比呈现同步变化趋势。Employing high-arsenic anthracite and employing a tubular furnace,the release of arsenic and the variation of arsenic speciation in ash under low-load coal combustion conditions was investigated.Results show that within the temperature range of 800-900℃,the release rate of arsenic from coal exhibits a significant peak with increasing temperature,while the proportion of As^(3+)in ash shows an upward trend.And the proportion of weak adsorbed arsenic in ash gradually increases within 800-900℃,which reaches its peak at 900℃.Within the range of 1000-1200℃,weak adsorbed arsenic in ash undergoes oxidation and decomposition,leading to an increase in the proportion of arsenate,prompting the transition of As^(3+)to As^(5+),and consequently,the proportion of As^(3+)decreases gradually.The increase of the volume fraction for O2 facilitates the oxidation process of As^(3+)in ash.Furthermore,with the extension of coal particle residence time in the furnace,the release rate of arsenic from coal synchronously varies with the proportion of As^(3+)in ash.

关 键 词：低负荷 煤燃烧 砷释放 砷价态 赋存形态 

分 类 号：TQ534[化学工程—煤化学工程] X773[环境科学与工程—环境工程]