The release of arsenic vapors (As³⁺) during high-arsenic coal combustion not only raises serious environmental concerns, but also causes catalyst deactivation in selective catalytic reduction (SCR) systems. To illuminate the mechanisms involved in the transformation of arsenic vapors towards less troublesome arsenates (As⁵⁺) during coal combustion, the accessory minerals in the high-arsenic coal were identified and the association relationship of these compounds with arsenic in fly ash was estimated. The results showed that Si/Al were the main inorganic elements in high-arsenic coal while the content of Ca was quite low. Ca was mostly transformed into sulfates during coal combustion and the effect of Ca on the arsenic transformation was limited. Al/Fe played a more significant role in arsenic speciation transformation and arsenic in the fly ash was predominantly bound with Al/Fe-oxides as arsenates. It was further confirmed that Al in kaolin/metakaolin showed good capacity on arsenic capture. In addition, few arsenic vapors were captured through the physical adsorption mechanism and the large fraction of As³⁺ in some fine particles was mostly attributed to the chemical reactions between arsenic vapors and Al-compounds. Meanwhile, a certain amount of arsenic vapors were converted into As₂O₅(s) under the influence of SCR catalyst and then carried by flue gas to participate in fly ash. Besides, part of arsenic distributed in the fly ash was through the stabilization of ash matrix in high temperature conditions. The transformation of arsenic from vapors towards particulate arsenic favored arsenic emission control by particulate matter control devices.

高砷煤燃烧过程中释放的砷蒸气（As ³⁺）不仅引起严重的环境问题，而且还导致选择性催化还原（SCR）系统中的催化剂失活。为了阐明涉及将砷蒸气转化为麻烦程度较小的砷的机理（As ⁵⁺）在煤燃烧过程中，鉴定了高砷煤中的辅助矿物，并估算了这些化合物与粉煤灰中砷的缔合关系。结果表明，Si / Al是高砷煤中的主要无机元素，而Ca含量却很低。Ca在煤燃烧过程中大部分转化为硫酸盐，并且Ca对砷转化的影响是有限的。Al / Fe在砷的形态转化中起着更重要的作用，粉煤灰中的砷主要与Al / Fe-氧化物作为砷酸盐结合。进一步证实高岭土/偏高岭土中的Al显示出良好的砷捕获能力。此外，通过物理吸附机理捕获的砷蒸气很少，而大部分As ³⁺一些细小颗粒中的杂质主要归因于砷蒸气与铝化合物之间的化学反应。同时，一定量的砷蒸气在SCR催化剂的作用下被转化为As ₂ O ₅（s），然后被烟气携带而参与飞灰。此外，飞灰中分布的部分砷是通过在高温条件下稳定灰分基质来实现的。砷从蒸气到微粒砷的转化有利于通过微粒物质控制装置控制砷的排放。