污水处理厂污泥制备吸附剂对燃煤烟气中汞的吸附性能研究

A kind of adsorbent made from wastewater sludge and its removal of mercury from flue gas

以城市污染处理厂的活性污泥作为原料，采用不同的活化方式处理制备出环境友好的吸附剂，可供燃煤电厂烟气中除汞。污泥活化后收率在40％～55％之间，物理活化后收率随活化温度的升高而降低，比表面积、孔隙量和吸汞量随活化温度的升高而逐渐增大，但吸汞量随温度升高而急剧下降，说明物理活化的吸附剂主要以物理吸附的方式除汞；经化学活化处理的吸附剂性能好、收率高，比表面积、空隙率和吸汞量显著增加，且除汞效率受温度影响较小，除汞效率高。淋滤实验结果验证了活化处理后的吸附剂对汞具有较高的吸附稳定性，没有二次污染。

Using city sewage sludge as a raw material, several new environment-friendly sorbents are prepared by different ways of activation, and used to remove mercury in flue gas from coal-fired power plants. The yield of the activated serbents can be 40% - 50%. After physical activation the yield is reduced along with the ascension of activation temperature, but the specific surface area, porosity and removal mercury value are increased gradually. However, the mercury removed drops rapidly with the temperate increment, which suggests that mercury is primarily or only physically adsorbed by carbonaceous materials on physically activated adsorbents. After chemically activated the sorbents have a excellent property, and its yield, specific surface area and mercury removal are increased observably. The efficiency of mercury removal is good and affected slightly by temperature. The restdts of the leaching test prove that the activated sorbents show a high mercury adsorption stability and have no secondary pollution.