水蒸气法制备污泥质活性炭的实验研究

以污泥和木屑为原料,采用管式炉水蒸气活化法,对流化床热解炉制得的热解炭进行制备活性炭的研究,分析了活化因素对活化效果的影响、亚甲基蓝在活性炭上的吸附平衡和动力学、污泥活性炭浸出液中重金属的含量及其孔结构等性能.实验结果表明:随着活化温度的升高、活化时间的延长和水蒸气流量的增加,活性炭的得率不断降低,亚甲基蓝的吸附值先升高后降低;污泥中添加20%木屑时制得的活性炭的吸附性能是纯污泥质活性炭的一倍多; Langmuir吸附等温线模型、准二级反应模型能够比较准确地描述亚甲基蓝在污泥活性炭上的吸附相平衡及吸附过程,平衡时活性炭对亚甲基蓝单层最大吸附量为71.43mg/g;污泥质活性炭的孔结构以过渡孔为主;浸出液中只有少量的重金属.

Study on preparation of activated carbon made from sludge by steam activation

Activated carbon prepared from sludge and sawdust by fluidized bed pyrolysis and tube furnace-steam activation method were studied.The effect of activation factors,adsorption equilibrium and kinetics of methylene blue on activated carbon,heavy metals in leachate and pore structure were investigated.The yield of carbon decreases all the way with the increase of activation temperature,activation time and flowrate of steam,while the adsorption performance increases first and then decreases.The adsorption properties of the product more than doubled when adding twenty percent of sawdust to the sludge.The Langmuir adsorption isotherm model and quasi-second-order reaction model can describe the methylene blue adsorption process and adsorption equilibrium on activated carbon in the sludge balance,during which the maximum adsorption capacity of methylene blue is 71.43 mg/g.Transition pores are more and there are only a small amount of heavy metals in leachate.