煤燃烧过程中痕量元素分布规律的实验研究

Experimental study of the distribution of trace elements during coal combustion

以流化床燃煤过程为研究对象 ,在实验室小型一维煤粉燃烧炉上进行实验 ,研究了煤燃烧过程中痕量元素的排放特点 .实验模拟流化床低温燃烧的特点 ,采用焦作无烟煤、西山贫煤、六盘水贫煤、萍乡烟煤、平顶山烟煤和小龙潭褐煤等 6种典型煤分别在 65 0℃ ,80 0℃和 95 0℃ 3个工况下燃烧 ,结果表明Hg在灰中几乎不富集 ,是易挥发的痕量重金属元素 ;Pb在灰中的含量随温度升高有下降的趋势 ,部分富集在细微颗粒上随烟气排出 ;Cr和Cd两种痕量元素大部分留在灰渣中 ,不易挥发 .

The emission of trace elements during the coal combustion processing in fluidized bed was studied. A laboratory-scale one order pulverized coal furnace was used to carry out experiments with six types of coals including Jiaozuo anthracite coal, Xishan lean coal, Liupanshui coal, Pingxiang bituminous coal, Pingdingshan bituminous coal and Xiaolongtan lignitous coal under various conditions (650?℃, 800?℃ and 950?℃). It was found that Mercury was volatile and emitted in the vapor phase. The content of Lead will reduce if the temperature rises. Lead will emit with gas enriching in the mini particles. Cadmium and Chromium remained in the ash and they are not volatile.