污水处理工艺中雌激素活性分布与去除途径分析

Analysis of the distribution and removal pathways of estrogenicity during wastewater treatment processes

摘要:

针对内分泌干扰物在水中质量浓度低、危害大、去除困难的现状,采用固相萃取/重组酵母法调查了城市污水厂各工艺过程中雌激素活性的分布并对其去除途径进行分析.结果表明:雌激素活性主要存在于液相中,悬浮态中只占7.7%±5.5%;雌激素活性的去除主要发生在二级生物处理过程,通过对二级生物处理过程进行质量衡算发现,吸附到剩余污泥中的雌激素活性占进水中的1.2%,对雌激素活性的去除主要依靠微生物降解(占73.9%).通过理论计算证实雌激素活性的去除途径主要是依靠微生物降解作用,通过污泥吸附和挥发去除非常有限(小于15%).总之,城市污水厂出水中雌激素活性仍然较高(3.37～6.76 ng.L-1),强化二级生物处理或者对污水深度处理迫在眉睫.

Abstract:

Endocrine disrupter chemicals(EDCs),with the characterization of low concentration,high toxicity,difficulty in removal from water,are receiving more and more attentions all over the world.The current study investigated the distribution of estrogenicity during wastewater treatment processes in Harbin using solid phase extraction/recombinant yeast system and analyzed the removal pathways of estrogenicity according to the results.Results showed that most of estrogenicity was distributed to liquid phase,whereas only(7.7±5.5) % of total estrogenicity was in the solid phase;it was also found that the secondary bio-process played a crucial role in the removal of estrogenicity,where the removal of estrogenicity took place mainly by biodegradation(73.9 %),whereas only 1.2 % was made through residual sludge adsorption.Last but not least,by calculating the removal of estrogenicity,it confirmed that less than 15 % of estrogenicity was removed through volatilization and adsorption,but mainly by biodegradation.Anyway,the estrogenicity of wastewater treatment plant effluent is still high(3.37-6.76 ng·L-1),so that the enhanced biotreatment processes or advanced treatment processes are desired to decrease the risk of estrogenicity.