好氧反硝化菌群的筛选及其培养条件的研究

从淮北焦化厂A2/O污水处理站二沉池的活性污泥中,采用焦化废水配制的牛肉膏蛋白胨固体培养基（DM100）分离纯化出7株反硝化细菌,并通过梯度添加焦化废水的平板驯化和液体驯化,在DO=2.5 mg/L的条件下复筛出4株具有抗逆性的优势好氧反硝化细菌,分别命名F4、F8、F9、F10.优势单菌株与组合菌群反硝化能力的对比试验表明,4株混合的好氧反硝化菌群生长快速稳定,在相同的试验条件下脱氮效率高于单菌株,48 h的NO3--N去除率为98.75%.4株混合菌群的最适生长条件为：35℃,pH=8.0,C/N比=5,接种量=25%（菌液浓度为（2~3）×107个/mL）.经过筛选和条件优化,优势菌群NO3--N去除率达到90%的降解时间由96 h降到18 h.

Screening of aerobic denitrifying bacteria and determination of the culture conditions

Seven strains denitrifying bacteria were isolated by beef extract peptone medium mixed with the coked waste water（DM100）,from Huaibei Coking plant ＇s activated sludge of the A2/O sewage treatment station.After gradient increase of coking waste water＇s plate domestication and liquid domestication,four strains aerobic denitrifying bacteria with high denitrification capacity and resistance to coking wastewater were isolated in aerobic condition.（DO=2.5 mg/L）,named F4,F8,F9,F10.The contrast experiment showed that four mixed aerobic denitrification bacteria had higher denitrification capacity and grew faster than single strain.Under the same condition,four mixed aerobic denitrification bacteria 48 h NO-3-N removal rate is 98.75 percent.And the most suitable culture conditions of them are： 35 ℃,pH=8.0,C/N=5,inoculate quantity is 25 percent（bacteria density is 2×107~3×107/mL）.After conditions optimization,the time of four mixed aerobic denitrification bacteria NO-3-N removal rate when attaining 90 percent reduced form 96 h to 18 h.