生物脱氮系统对重金属的耐受性研究

工业废水和生活污水合并集中处理是未来城市污水处理厂的趋向。根据工业废水中常见的Cu2+和Zn2+两种重金属离子,研究了生物脱氮系统对Cu2+和Zn2+的耐受性。试验发现ρ(Cu2+)>0.5 mg/L对生物脱氮系统中COD和TN的去除产生明显的破坏作用,ρ(Cu2+)>5 mg/L对NH 4+-N的去除影响较大,对硝化过程产生抑制作用。ρ(Zn2+)>30 mg/L时对生物脱氮系统的有机物、NH 4+-N和TN的去除产生明显的影响。通过逐渐提高Cu2+、Zn2+浓度对生物脱氮系统进行驯化,可显著提高微生物对重金属的适应性和耐受性,保证污水处理效率。

STUDY ON THE TOLERANCE OF HEAVY METALS IN BIOLOGICAL DENITRIFICATION SYSTEM

Future tendency of municipal wastewater treatment plant is that domestic sewage will be combined with industrial wastewater to be treated.In this paper,the tolerance of heavy metals in biological denitrification system was studied according to Cu2 + and Zn2 + which were the most common ions in industrial wastewater.When Cu2 + was more than 0.5 mg /L,the removal of COD and TN was destroyed.It was found that which had inhibiting effect on biological nitrogen when Cu2 + was more than 5mg /L based on tests.The zinc ion would influence the removals of COD,NH 4+-N and TN when Zn2 + was only more than 30 mg /L.The tolerance and adaptability of microorganisms for heavy metals were significantly increased in biological denitrification system by gradually increasing the concentrations of Cu2 + and Zn2 + and the efficiency of wastewater treatment was ensured.