Study On The Treatment Of Toluene By Biotricking Filter

A large number of pollutants are emitted in the atmosphere every day,in which volatile organic compounds（VOCs）are an important component of pollution and have become a bottleneck problem of air pollution control because of the wide range of emissions.As one of representatives of volatile organic compounds,toluene,will damage the skin,blood and all sorts of nervous system.With the development of city traffic and industry,the amount of volatile organic compounds emissions is more and more,so it is imminent to develop an efficient purification method.This experiment used attapulgite clay,sawdust and manganese powder as the filler,then purified and decontaminated toluene after the formation process of biofilm.We studied the fabrication of Manganic Oxide-based Porous Ceramsite,the startup method of biotrickling filter,the influence of various conditions on the operation efficiency of the biotrickling filter,the optimum operating conditions,the operation characteristics of the biotrickling filter system and so on.The results of the studies are listed as follows:（1）Manganese powder,attapulgite clay and sawdust were used as raw material in a proportion of 10:7:2,and calcined in air at 700 degrees for 3 hours.The ceramsite prepared in this condition had high compressive strength,interlinked inner holes and large specific surface area.The ceramsite prepared in this condition conformed to the national standard for water treatment.It was appropriate for microbe film hanging.And the ceramsite could be used as filler.（2）The waste gases containing toluene could reach their highest removal efficiency at a temperature of 22 to 30℃ and a pH of 6.2⁷.0.At this point,the inlet toluene mass concentration was below 400mg/m3,the EBRT was 70 s,the liquid flow rate was 90ml/min,and the removal rate could be above 80%.（3）Biotrickling filter could produce CO₂ in the process of purifying the waste gas containing toluene.The concentration of CO₂ rose as inlet toluene concentration increasing.But its degradation rate was reducing.And the proportion of the theoretical CO₂ production to the actual CO₂ production was lower and lower.（4）The biotrickling filter restoring inlet for 24 hours after 10 days of inoperation could effectively remove toluene,and the running stability was good.