煤种及热解条件对煤焦脱除烟气汞的影响

Effect of Coal Type and Pyrolysis Condition on Removal Efficiency of Flue Gas Mercury by Coal Char

在固定床汞吸附机理研究试验台上,利用X射线光电子能谱仪和Autosorb-1-C吸附仪研究了煤种、热解温度及热解时间对煤焦汞吸附特性的影响.结果表明:煤种是影响煤焦吸附气态汞的重要因素,在相同制取条件下,褐煤焦的汞脱除效率达90%以上,明显高于烟煤焦不到40%的汞脱除效率.在热解时间不变的条件下,随着热解终温的升高,汞脱除效率明显提高,穿透率下降;在热解终温不变的条件下,随着热解时间的延长,汞脱除效率先提高后降低,当热解时间为30min时,汞脱除效率最高.

Effect of coal type, pyrolysis temperature and time on mercury adsorption by coal char was studied in a bench-scale fixed bed by using X-ray photoelectron spectroscopy and Autosorb-1-C analyzer. Re- sults show that the rank of coal seems to have a large effect on the adsorption of mercury vapors; under the same production conditions, the removal efficiency by lignite char is above 90%, obviously higher than that by bituminous char below 40 %. For the same pyrolysis time, the removal efficiency increases and the breakthrough time reduces with rising pyrolysis temperature. At the same pyrolysis temperature, the mercury removal efficiency increases first and reduces later on with rising pyrolysis time, which reaches the highest at a pyrolysis time of 30 min.