污泥堆肥微生物菌剂的筛选优化及应用

从菌糠腐熟物中分离纯化12株长势良好的菌株,经16SrDNA测序分析,鉴定为链霉菌(Streptomyces sp.),将其中长势最好的一株命名为链霉菌P9。通过单因素实验及Plackett-Burman实验设计对链霉菌P9发酵培养基配方进行优化,得到培养基最佳配方为蔗糖10g/L,蛋白胨+酵母粉25.0g/L,MgSO4·7H2O 0.075g/L,KH2PO40.3g/L,K2HPO40.6g/L。将最佳培养基配方下制得的链霉菌P9发酵液用于污泥好氧堆肥,接种量分别为0(对照组CK)、0.5%(质量分数,下同)、1.0%、1.5%。结果表明,当接种量为0.5%时,堆体最高温度可达61.0℃,高温期维持12d,堆肥效果程度优于CK组(堆体最高温度58.1℃,高温期维持9d),接种量为1.0%、1.5%时污泥堆肥进程反而被抑制。堆肥结束时,堆体上清液的种子发芽指数均在70%以上,说明堆体物料基本腐熟无毒。可见,采用链霉菌P9发酵液作为微生物菌剂促进污泥好氧堆肥是可行的,接种量宜为0.5%。

Screening and optimization of microbial agents and its application in sludge composting

12 strains were screened and purified from fungus chaff humus.They were identified as Streptomyces sp.by 16 SrDNA sequencing identification and the best one was named as Streptomyces P9.Single factor experiment and Plackett-Burman experiment design were applied to optimize the culture medium formula.The optimal formula of culture medium was 10 g/L sucrose,25.0 g/L peptone+yeast powder,0.075 g/L MgSO4·H2O,0.3 g/L KH2PO4 and 0.6 g/L K2HPO4.Under the optimal culture medium formula,the obtained fermentation broth was inoculated into the aerobic sludge composting at the mass ratio of 0(control group CK),0.5%(mass ratio,the same below),1.0%and 1.5%.The composting experiment results showed that the maximum temperature could reach 61.0℃ when the inoculation amount was 0.5%,and the high temperature period maintained for 12 days.For the CK group,the maximum temperature was 58.1 ℃ and the high temperature period maintained for 9 days.When the inoculation amounts were 1.0% and 1.5%,the sludge composting process was inhibited.At the end of the composting,the seed germination index of the compost supernate was above 70%,which indicated that the compost material was almost mature.So,it was feasible to apply Streptomyces P9 fermentation broth as microbial agents to promote sludge aerobic composting,and the suitable inoculation amount was 0.5%.