SDS对生物滴滤器处理正己烷气体及生物膜分泌物组成的影响

Effect of SDS on gaseous n-hexane biodegradation and components of the biofilm exudate in biotrickling filters

利用两套相同实验室规模的生物滴滤器(Biotrickling filters,BTFs)(BTF1对照组和BTF2添加表面活性剂SDS)进行表面活性剂SDS强化正己烷生物降解实验,对比分析了正己烷在3种表面活性剂SDS、Tween20和Triton X-100中的分配系数(K),并在正己烷进口负荷为72 g·m-3·h-1的条件下探讨了SDS添加量对生物滴滤器性能和不同填料层生物膜分泌物组成的影响.结果表明,正己烷在3种表面活性剂中的分配系数要远低于其在水中的分配系数,且在SDS中的分配系数最低.由于SDS的添加能促进正己烷在水中的溶解度,SDS浓度在158.6mg·L^(-1)时,正己烷的去除率从50%(BTF1)增加到70%(BTF2),相应的去除能力达到50.4 g·m-3·h-1.但作为碳源,高浓度SDS与正己烷之间存在竞争作用,当SDS浓度为475.8 mg·L^(-1)和793.0 mg·L^(-1)时,BTF2对正己烷的去除性能低于BTF1的.BTF1第2层填料上生物膜分泌的蛋白质和多糖含量要高于其它几层填料,而当BTF2中SDS浓度在158.6 mg·L^(-1)时,第2层填料上生物膜分泌的蛋白质含量和多糖均高于BTF1中第2层填料.

Two sets of the same lab-scale biotrickling filters（ BTF1 as a control group and BTF2 for the addition of SDS） were used to study the intensifying effect of SDS on the biodegradation of n-hexane. The partition coefficients（ K） of n-hexane in three surfactants（ SDS,Tween 20 and Triton X-100） were evaluated,and the effects of the SDS addition on the removal performance of BTFs and the component of the biofilm exudate were investigated at a fixed n-hexane loading rate of 72 g·m-3·h-1. Results indicated that the coefficients（ K） of n-hexane in surfactant solutions were much lower than that in water,and the lowest value was observed in the SDS solution. Due to the increase of the n-hexane solubility in water with the addition of SDS,the removal efficiency of n-hexane increased from 50%（ BTF1） to 70%（ BTF2） at 158.6 mg·L^（-1） SDS and the corresponding elimination capacity（ EC） of50.4 g·m-3·h-1 was achieved. However,as a carbon source,a high concentration of SDS competed with n-hexane. As a result,the removal performance of BTF2 was lower than that of BTF1 when the concentrations of SDS were 475. 8 mg·L^（-1） and 793. 0 mg·L^（-1）. The concentrations of the biofilm-secreted protein and polysaccharide in the second packing medium layer of BTF1 were higher than those in the other packing medium layers of BTF1,but always lower than those in the second packing medium layer of BTF2 for the SDS concentration of 158.6 mg·L^（-1）.