污水深度处理投加聚合氯化铝对微生物活性的影响

分析江苏某城市污水处理厂聚合氯化铝(PAC)的投加对污水中铝离子以及微生物活性的影响。结果表明:低浓度的铝离子会增强微生物的活性,但浓度过高会对微生物产生抑制作用,当铝离子质量浓度为7.5mg/L时,对微生物的活性没有影响;当铝离子的质量浓度达到10mg/L时,对微生物活性会产生抑制作用;以微絮凝-砂滤工艺作为城市污水处理厂的深度处理工艺时,投加的聚合氯化铝质量浓度不宜超过12.5mg/L,当质量浓度达到15mg/L时,铝离子会对好氧池的微生物活性产生明显的抑制作用。

Effect on microorganism activity of adding PAC in advanced wastewater treatment

The influence of polymeric aluminium chloride(PAC) on the aluminum ion and microorganism activity in wastewater was studied.A case study was conducted in a wastewater treatment plant in a city in Jiangsu Province.The results show that a low concentration of aluminum ion will improve the activity of microorganisms,while a high concentration of aluminum ion will have an inhibitory effect on microorganism activity.When the aluminum concentration was 7.5 mg/L,there was no influence on the activity of microorganisms.When the concentration reached 10 mg/L,it had an inhibitory effect on the activity of microorganisms.During the advanced wastewater treatment process using the micro-flocculation sand filtration technique,a suitable PAC concentration should be less than 12.5 mg/L.Obvious inhibition on the activity of microorganisms could be observed in the aerobic tank when the aluminum concentration reached 15 mg/L.