Removal characteristics of organic pollutants by the adsorbent injection coupled with bag filtering system

摘要

Activated carbon (AC) injection coupled with bag filtering (ACI+BF) is a promising technology for the organic pollutant treatment in the flue gas of coal-fired power plants. The removal characteristics of six volatile organic compounds (VOCs) and adsorption pathways were investigated in a self-designed ACI+BF system. The results suggested that o-xylene had the highest removal efficiency and that was the lowest for benzene, which was influenced by their boiling points and saturated vapor pressures. The physicochemical properties of AC changed slightly after VOCs adsorption in the ACI+BF system. The VOCs removal process was dominated by physical adsorption even if the adsorption temperature was higher. With the increasing of adsorption temperature and VOCs concentration, the removal efficiency reduced; while that increased with increasing the AC feeding rate and residence time. The VOCs removal by the ACI+BF system could be divided into two processes, including the adsorption in pipeline and adsorption in the bag filter. Bag filter had an important contribution to the total removal efficiency. Increasing the length of the pipeline and reducing the dust cleaning frequency of the filter bag were useful in enhancing the organic pollutants removal efficiency.