硫化氢降解菌包埋条件及降解特性研究

Embedding Conditions and Degradation Characteristics of Combined Hydrogen Sulfide Degrading Bacteria

筛选获得2株硫化氢（H2S）高效降解菌株（T3和B3）,分别鉴定为根瘤杆菌属和人苍白杆菌属。采用改进的海藻酸钠（SA）-聚乙烯醇（PVA）对2株菌的混合液进行包埋,并对最佳包埋条件及包埋后的降解效果进行研究,结果表明：SA-PVA包埋的最佳条件：复合载体的配比为2%SA和7%PVA混合溶液;在1%氯化钙和4%硼酸混合溶液中交联24 h;制得粒径为2 mm左右的固定化凝胶小球;包菌量为0.3 g/L;在pH 5.0~10.0、温度为25~40℃时,固定化细胞对H2S具有较高的降解能力和抵抗性,当H2S浓度提高到700 mg/m3以上时,48 h后固定化细胞能达到93%以上的降解率,并且其重复脱硫能力明显优于游离态细胞,为工业应用提供了可能性。

Two hydrogen sulfide degrading bacteria（T3 and B3）isolated and identified as Rhizobium sp.and Ochrobactrum sp.were embedded with improved sodium alginate（SA）-polyvinyl alcohol（PVA）,and the optimal embedding conditions and efficiency of degradation after embedding were studied.It was found that the optimal embedding condition was fixed on 2% SA and 7% PVA,24 h for cross-linking time in mixed solution of 1% calcium chloride and 4% boric acid,2~3mm for particle size of embedded cells,0.3 g/L of package bacteria.At pH 5.0~10.0,temperature 25~40 ℃,the immobilized cells had higher H2S degradation ability and better resistance to H2S than that in free-state cells.When H2S concentration was raised above 700 mg/m3,the removal rate of degrading bacteria can reach 93% after 48 h reaction.Its desulfurization ability was significantly higher than that in free-state cells,which would provide possibility for industrial applications.