CAJ | 학술논문

选取3个煤阶共6个国内典型煤种，利用水平管式炉在不同温度下进行煤的燃烧实验，研究燃煤过程中砷的迁移和释放特性。利用热分析的相关理论和方法，将煤的热重分析手段运用于煤燃烧过程中砷的质量变化，通过对实验结果进行拟合得到砷的失重曲线和失重速率曲线，并采用逐级化学提取的方法对原煤及不同温度下煤灰中砷的赋存形态进行分析。25～1100℃的实验结果表明：随着温度升高，煤中砷的释放比例逐渐增大，1100℃下砷的释放比例变化范围为30%～67%。不同温度区间下砷的失重速率存在差异，800～900℃区间出现显著的砷失重峰，主要原因是以硫化物形式存在的砷在800～900℃区间发生剧烈的分解/氧化分解。此外，相同温度下褐煤的失重比例和失重速率较大，无烟煤的失重比例和失重速率较小，烟煤则介于无烟煤和褐煤之间。温度升高后，煤中的有机物结合态砷向气相迁移，酸溶态砷和残渣态砷共同作用，减少的砷主要进入气相中，还有一部分向可交换态砷迁移。
선취3개매계공6개국내전형매충，이용수평관식로재불동온도하진행매적연소실험，연구연매과정중신적천이화석방특성。이용열분석적상관이론화방법，장매적열중분석수단운용우매연소과정중신적질량변화，통과대실험결과진행의합득도신적실중곡선화실중속솔곡선，병채용축급화학제취적방법대원매급불동온도하매회중신적부존형태진행분석。25～1100℃적실험결과표명：수착온도승고，매중신적석방비례축점증대，1100℃하신적석방비례변화범위위30%～67%。불동온도구간하신적실중속솔존재차이，800～900℃구간출현현저적신실중봉，주요원인시이류화물형식존재적신재800～900℃구간발생극렬적분해/양화분해。차외，상동온도하갈매적실중비례화실중속솔교대，무연매적실중비례화실중속솔교소，연매칙개우무연매화갈매지간。온도승고후，매중적유궤물결합태신향기상천이，산용태신화잔사태신공동작용，감소적신주요진입기상중，환유일부분향가교환태신천이。
Migration and volatilization features of arsenic in combustion processes for six coal samples selected from three different ranks were studied in a horizontal tube furnace at various temperature ranges. The mass change of arsenic in the combustion process was tracked and analyzed using the instruments and theoretical method of thermal analysis (TG/DTG) and coal analysis for these selected coal samples. The curves of arsenic mass loss and its rate were obtained by fitting these experimental results. The occurrence form of arsenic in the coals and corresponding ashes was determined by using a sequential chemical leaching method. The experimental results show that arsenic volatility and the releasing proportion increase with temperature, and the proportions varied from 30% to 67% at 1100℃. The mass loss rate of arsenic varies for different temperature regions, and a peak value of arsenic loss rate is observed at 800—900℃, mainly due to decomposition/oxidation of arsenic in sulfide form. Furthermore, lignite shows the highest mass loss ratio and rate of arsenic under the same temperature, followed by bituminous coals and anthracite. With temperature increases, organic arsenic volatiles easily into gas phase, and the interaction between acid-soluble and residual arsenic makes them migrate mainly into gas phase, and only a small part is transferred to its exchangeable form.