微波法制备污泥活性炭研究

采用微波加热法,以污水厂剩余污泥为原料,磷酸为污泥活化剂制备污泥活性炭.微波功率、辐照时间和磷酸浓度对污泥活性炭吸附性能具有显著影响,在最佳工艺条件微波功率480 W、辐照时间315 s和磷酸浓度40%条件下制得的活性炭碘值301 mg/g,比表面积168 m2/g,污泥中重金属绝大部分被固化.与传统商品炭相比,污泥炭孔隙结构以中孔为主.利用该活性炭处理城市生活污水处理厂出水,COD去除率可达87%以上,污泥炭的吸附等温线用Langmuir等温吸附模型进行描述.

Study on activated carbon made from sewage sludge by microwave

Sludge-based activated carbon was made from surplus sewage sludge in an urban wastewater treatment plant by microwave heating. Phosphoric acid (H₃PO₄) was used as a sludge activating agent during the pyrolytic process. Microwave power, irradiation time and the concentration of H₃PO₄ had remarkable influences on the adsorption performance of the sludge-based activated carbon. The activated carbon prepared under the optimal conditions of microwave power 480W, irradiation time 315s and 40% concentration of H3PO4 had a surface area of 168m²/g and an iodine adsorption value of 301mg/g. In addition, the heave metals in the source sludge had been solidified in the course of microwave heating.Compared with the traditional commercial carbon, the sludge-based activated carbon was mainly mesoporous in nature. Finally, the sludge-based activated carbon as an adsorbent was employed for disposing COD in effluent of the urban sewage treatment plant. The aqueous adsorption test indicated that the sludge-based activated carbon had a notable adsorption capacity for COD and the removal efficiency of COD was more than 87%. The equilibrium data fitted well in the Languir model of adsorption.