聚乙烯醇降解菌剂的制备及处理废水研究

筛选聚乙烯醇(PVA)降解中间产物的高效降解菌,与PVA降解菌制成复合微生物菌剂,根据营养需求加入助剂,用正交试验法优化菌剂的处理条件,并对菌剂系统的启动情况、运行稳定性、PVA含量对系统处理效率的影响、适宜的HRT进行探讨。结果表明,优化的菌剂中红球菌P-2、共生菌B1+B2、羟基酮降解菌S-1和β-双酮降解菌T-4的体积比为3:1:2:1、助剂配比为m(酵母汁):m(NH4NO3):m(吡咯喹啉醌)=1.0:0.4:0.01;菌剂系统与活性污泥相比,启动时间少3 d,PVA降解率高约40个百分点;系统更稳定,连续运行6月,PVA降解率和降解活性分别维持在80%和2 U/mL以上;最高耐受负荷约为2 000 mg/L,比活性污泥高约1 200 mg/L;菌剂优化的废水处理条件为:温度35℃、助剂加入量1 g/L、pH=7,DO的质量浓度为3 mg/L;PVA的质量浓度分别小于1 000 mg/L和1 000～2 000 mg/L时,适宜的HRT分别为18 h和36 h。

THE CONSTRUCTION OF PVA -DEGRADING MICROORGANISM AGENT AND THE TREATMENT OF PVA WASTEWATER

High-efficiency microbes which can degrade intermediate products of PVA were screened and mixed with high-efficiency PVA-degrading strains according to a fixed ratio to construct PVA-degrading microorganism agent.Aid agent was added based on nutritional requirements.Orthogonal experiment was used to optimize treatment conditions of the microorganism agent.The start-up time,stability of operation,the influence of PVA concentration on the PVA removing rates,hydraulic retention time(HRT) were discussed.The results reveal that the proper ratios of the microorganism agent are as follows: V(P-2):V(B1+B2):V(S-1):V(T-4)=3.0:1.0:2.0:1.0;the proper ratios of the aid agents are that m(yeast water):m(NH4NO3):m(PQQ)=1.0:0.4:0.01.Compared with activated sludge,it is featured by a short start-up time(3 d),higher PVA removal rate(40%).Constantly operating 6 months,PVA removal rates keep above 80%,PVA ase activity keep above 2 U/mL.The PVA permissible load was 2 000 mg/L,1 200 mg/L higher that of activated sludge system.The proper treat conditions are that temperature(35 ℃),the concentration of aid agent(1 g/L),pH(7),dissolved oxygen(3 mg/L).When the PVA concentration is lower than 1 000 mg/L,the proper HRT is 18 h,while when the PVA concentration is 1 000～2 000 mg/L,the proper HRT is 36 h.