低浓度Cr(Ⅵ)对颗粒化强化生物除磷(EBPR)系统的影响及系统恢复研究  

Effects of exposure to low concentrations of Cr(Ⅵ) on granule-based enhanced biological phosphorus removal (EBPR) systems and their recovery

作　　者：苏斌[1] 孙培德[1] 方婧[1] 汤秀娣[1] 徐少娟[1] 

机构地区：[1]浙江工商大学环境科学与工程学院,杭州310012

出　　处：《环境科学学报》2013年第5期1231-1238,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.21276236);浙江省重大科技专项重点社会发展项目(No.2010C03003;2011C13014);国家"十一五"水体污染控制与治理科技重大专项(No.2009ZX07106-002);浙江省教育厅项目(No.Y200907043);浙江省高等学校创新团队支持计划资助项目(No.T200912);浙江工商大学研究生科技创新项目(No.1260XJ1512148)~~

摘　　要：低浓度Cr(Ⅵ)对颗粒化强化生物除磷(EBPR)系统长期暴露的试验结果表明,Cr(Ⅵ)投加浓度≤0.3mg·L-1时,系统磷酸盐及COD去除率基本不受影响;而当Cr(Ⅵ)浓度高于0.3mg·L-1时,系统除磷及除COD能力逐渐丧失.聚磷菌(PAOs)对Cr(Ⅵ)的毒性敏感性大于聚糖菌(GAOs)和其他菌.当Cr(Ⅵ)浓度高于0.3mg·L-1时,聚磷菌占系统全菌的比例从84.26%下降到38.40%,聚糖菌比例则从8.04%上升为28.16%,其他菌的比例从7.70%上升到33.44%.这说明在Cr(Ⅵ)毒性作用下,聚磷菌的减少是导致颗粒化EBPR系统除磷能力丧失的主要原因.相关性分析结果表明,系统菌体内Cr浓度与系统磷去除及COD去除效率均呈显著负相关关系,说明Cr在菌体内累积是导致颗粒化EBPR系统磷酸盐和COD去除效率下降的重要原因.此外,受到Cr(Ⅵ)冲击的颗粒化EBPR系统,其磷酸盐和COD去除率在15d之内均可恢复至毒性试验前水平,且最终聚磷菌能够重新成为系统内的优势菌群.The effect of Cr（Ⅵ） concentration on granule-based enhanced biological phosphorus removal （EBPR） system was studied using long-term exposure test. The results showed that low concentrations of Cr（Ⅵ） （less than 0.3 mg·L^-1） had no influence on P and COD removal efficiency. However, P and COD removal capability in the system was completely inhibited in the presence of Cr（Ⅵ） over 0.3 mg·L^-1. Phosphate accumulating organisms （PAOs） was much more sensitive to Cr（Ⅵ） than glycogen accumulating organism （GAOs） and other bacteria. When the concentration of Cr（Ⅵ） was more than 0.3 mg·L^-1, the population of PAOs reduced from 84.26% to 38.40%, but GAOs and other bacteria raised from 8.04% to 28.16% and from 7.70% to 33.44%, respectively. The phenomenon indicated that the decrease of PAOs in granule-based EBPR system was directly responsible for the decrease of P removal efficiency. Correlation analysis showed that both P and COD removal efficiencies were significantly negatively correlated to the intracellular Cr, implying that the accumulation of intracellular Cr was an important factor inducing decline of P and COD removal efficiency. In addition, P and COD removal performances with long-term Cr（Ⅵ） shock could revive after 15 days＇ recovery treatment, and finally PAOs could be enriched again in granule-based EBPR system.

关 键 词：Cr(Ⅵ) 颗粒化强化生物除磷(EBPR) 宏观特征 菌群变迁 恢复试验 

分 类 号：X703.1[环境科学与工程—环境工程]