污泥活性炭固定床吸附甲苯

采用ZnCl2化学活化法制备的污泥活性炭用于固定床吸附甲苯实验,研究了吸附剂床层厚度、甲苯初始浓度、气体线速等操作条件对其吸附性能的影响,并建立了污泥活性炭吸附甲苯的传质模型,计算不同操作条件下的传质区长度和物质总传质系数。结果表明,当床层厚度从3 cm增加到7 cm,传质区长度基本不变,物质总传质系数增加了66.66%;当甲苯初始浓度增大3.36倍,传质区长度增加了17.19%,而物质总传质系数降低了22.05%;在实验流速范围内,气体线速变为原来的2倍,物质总传质系数增加了65.27%,说明污泥活性炭对甲苯吸附属于外扩散控制。

Adsorption of toluene by fixed sludge-based activated carbon bed

Sludge-based activated carbon was produced by ZnCl₂ chemical activation of dewatered sludge, and was used as adsorbent for toluene in fixed bed. At the same time, the effects of bed depth, initial concentration and gas linear velocity on removal of toluene were studied, and mass transfer model for this process was established to calculate mass transfer zone and total mass transfer coefficient. Results show that with bed depth changing from 3 cm to 5 cm, mass transfer zone has no significant change, while the total mass transfer coefficient increases by 66.66%; mass transfer zone increases by 17.19% and total mass transfer coefficient reduces by 22.05%with the toluene concentration increasing by 3.36 times. In the operation of the gas linear velocity range, with the gas linear velocity double than that of the original, total mass transfer coefficient increases by 65.27%, which indicates that this process belongs to external diffusion control.