烟草薄片废水絮凝预处理配方优化与验证

Optimization and Validation of Flocculation Pretreatment Formula of Tobacco Slice Wastewater

为了提高烟草薄片生产废水絮凝处理效率,以某烟草薄片实际废水为研究对象,考察絮凝剂、助凝剂种类及用量、初始pH等因素对废水絮凝效果的影响,在此基础上,采用响应面法对絮凝剂、助凝剂的种类和用量,以及废水pH等因素进行优化。利用多级A/O模拟反应器研究了优化配方对生化池微生物群落结构及出水水质的影响,结果表明:以聚合氯化铝(PAC)为絮凝剂,阳离子聚丙烯酰胺(CPAM)和Ca(OH)_(2)为助凝剂,用量分别为93.76 mg·L^(-1)、17.10 mg·L^(-1)、1.00 mg·L^(-1),pH为8.00时可达到最佳絮凝效果,此时SS、色度和COD的去除率分别为90.85%、92.50%和25.24%,与原絮凝剂配方相比可节省药剂成本30%以上。对生物反应器中菌群结构分析表明,优化后的絮凝剂配方不会影响生化处理效果,并且可改善原工艺系统中疣微菌门(Verrucomicrobiota)大量繁殖所带来的浮泥问题。

The influencing factors of flocculation effect such as types and dosage of flocculant and coagulant aid,the initial p H of wastewater were investigated to improve the efficiency of tobacco slice wastewater flocculation treatment.Response surface methodology(RSM) was applied to optimize the types and dosage of flocculant and coagulant aid,as well as the p H of wastewater.The effects of optimized formula on microbial community structure and effluent quality of biochemical tank were studied by using multistage A/O simulation reactor.The results showed that the best flocculation efficiency could be achieved when polyaluminium chloride(PAC) was used as flocculant,cationic polyacrylamide(CPAM) and Ca(OH)_(2) were used as coagulant aids,with dosages of 93.76 mg·L^(-1),17.10 mg·L^(-1) and 1.00 mg·L^(-1),respectively,and the p H=8.00.In this case,the removal efficiencies of SS,chroma and COD are 90.85%,92.50% and 25.24% respectively.Compared with the original flocculant formula,the reagent cost could be saved by more than 30%.The analysis of the microbial community structure in the bioreactor showed that the optimized flocculant formula would not affect the biochemical treatment efficiency,and helped to solve the floating mud problem caused by the mass reproduction of verruco microbiota in the original process system.