剩余污泥制备活性炭及其应用研究

以城市污水处理厂二沉池排出的剩余污泥为原料，采用不同活化方法制备活性炭，同时对比活化效果，研究了制备工艺条件对污泥活性炭吸附性能及产率的影响。结合比表面积、孔径分布和扫描电镜表征分析，对制备的污泥活性炭的性能进行评价，并探讨了污泥活性炭作为水处理吸附剂的去除效果。结果表明，以ZnCl2为活化剂制备的活性炭性能较好，其最佳制备条件为：活化温度550℃，活化时间45 min，ZnCl2浓度40％，固液比1∶2。制得的污泥活性炭的碘吸附值为496 mg/g，产率为51.8％，比表面积为301.4 m2/g,孔体积为0.37 mL/g，微孔体积为0.08 mL/g，平均孔径为5.78 nm。将该产品用于处理城市污水，投加量为0.8％，吸附平衡时间约为60 min时，对COD的去除率为81％，吸附容量为42.53 mg/g。

Study on preparation of activated carbon from excess activated sludge and its application

The surplus sludge of secondary settling tanks from sewage treatment plant were used as raw material to produce activated carbon by different activation ways. Different activation effects were compared and the impacts of preparation conditions on the adsorption performance and mass yield of sludge activated carbon were studied. BET surface area, pore size distribution and SEM photography were analyzed to evaluate the performance of sludge activated carbon. The effects of sludge activated carbon as an adsorbent for urban sewage treatment were also studied. The result showed that ZnCl2 was the best activation agent, and the optimum preparation conditions were activation temperature 550℃, time of activation 45 min, concentration of ZnCl2 40%, the ratio of solid to liquid 1∶2. The iodine adsorption number of the sludge activated carbon was 496 mg/g, mass yield was 51.8%， BET surface area was 301.4 m2/g.Total pore volume, micropore volume and average pore diameter were 0.37 mL/g, 0.08 mL/g and 5.78 nm respectively. When it was used as adsorbent for urban sewage treatment, under the conditions that the amount of sludge activated carbon added was 0.8%and the equilibrium adsorption time was about 60 min, the removal rate of COD was 81%, the equilibrium adsorption capacity was 42.53 mg/g.