两种填料对生物滴滤塔净化甲苯废气性能影响

Effect of two kinds of fillers on the performance of toluene waste gas purification by biotrickling filter

[目的]探究并对比泡沫陶瓷及聚二甲基硅氧烷(PDMS)复合泡沫陶瓷分别作为生物滴滤塔填料时净化甲苯废气的性能。[方法]以该两种材料作为生物滴滤塔填料,比较两台生物滴滤塔的挂膜速度,改变停留时间及营养液中氮源对生物滴滤塔性能的影响。[结果]第6d,入口浓度为1000 mg/m3、EBRT为38.9s时,PDMS生物塔可以达到80%的去除率,而泡沫陶瓷生物塔仅有40%的去除效率。待稳定运行后,当EBRT为38.9s,进口浓度为600 mg/m3时,两台生物塔尾气中甲苯含量均可达到未检出水平,当EBRT为31.1s时,泡沫陶瓷生物塔的去除效率仍可以达到95%,而PDMS生物塔可以达到99%。当消除营养液中存在的碳源后,生物塔可以稳定高效运行,在整个运行过程中PDMS生物塔的压降一直小于泡沫陶瓷生物塔。[结论]由于PDMS材质良好的生物亲和性,PDMS生物塔挂膜速度要快于泡沫陶瓷生物塔,在运行的整个过程中PDMS复合生物塔的性能优于泡沫陶瓷生物塔,且由于PDMS良好的疏水性,使得整个过程中保持着低压损的效果。

[Objective]To investigate and compare the performance of toluene waste gas purification by using foam ceramics and polydimethylsiloxane(PDMS)composite foam ceramics as biotrickling filter packing respectively.[Method]The biofilm formation,residence time and nitrogen sources in nutrient solution were compared between the two biotrickling filter with these two materials as fillers.[Result]On the sixth day,when the inlet concentration was 1000 mg/m3 and EBRT was 38.9 s,the removal rate of PDMS biotrickling filter could reach 80%,while the removal efficiency of foam ceramic biotrickling filter was only40%.After stable operation,when the EBRT is 38.9 s and the inlet concentration is 600 mg/m3,the toluene content in the tail gas of the two towers can reach the undetected level.When the EBRT is 31.1 s,the removal efficiency of the foam ceramic tower can still reach 95%,while the PDMS tower can reach 99%.When the carbon source exists in the nutrient solution is eliminated,the biotrickling filter can operate stably and efficiently.The pressure drop of PDMS biotrickling filter is always smaller than that of foam ceramic biotrickling filter during the whole operation.[Conclusion]Due to the good bioaffinity of PDMS material,the film mounting speed of PDMS biotrickling filter is faster than that of foam ceramic biotrickling filter.In the whole process of operation,the performance of PDMS composite biotrickling filter is better than that of foam ceramic biotrickling filter.Moreover,due to the good hydrophobicity of PDMS,the effect of low pressure loss is maintained in the whole process.