【作者】 朱光灿；

【导师】 王超； 吕锡武；

【作者基本信息】 河海大学 ， 环境工程， 2004， 博士

【摘要】 微囊藻毒素（MC）是一类七肽单环肝毒素，MC-LR是一种强烈的肝脏肿瘤促进剂。MC在水中的化学稳定性较好，不能被传统净水工艺有效去除，迫切需要寻求能有效去除饮用水中MC的实用水处理工艺。 本文完善了MC的ELISA和HPLC分析方法，通过模拟试验及水厂实测调查了富营养化太湖水中MC在常规净水工艺中的去除特性，结果表明预氯化使藻细胞内的MC释放出来，混凝沉淀对细胞外MC无去除作用，砂滤可去除17.2％～40.4％的细胞外MC和19.0％～36.6％的总MC，加氯消毒对细胞外MC和总MC的去除率分别为30％～45.3％和30％～51.7％。 接近于推流反应器的三阶生物接触氧化反应器对富营养化原水的预处理效果与稳定性优于单阶生物接触氧化反应器。HRT为2h时，三阶生物接触氧化工艺对氨氮、NO₂^--N、浊度和藻类的去除率大于90％，COD_Mn的去除率大于20％，细胞外MC和总MC的去除率分别大于85％和84％，细胞外MC-RR和MC-LR的去除率分别达到81.7％和86.7％以上，总MC-RR和MC-LR的去除率分别达到80.5％和71.5％以上。综合对各污染物的去除效果，阶式生物反应器三阶的气水比分别取2:1、0.5～1:1和0～0.5:1。生物预处理工艺中，MC在特定细菌的降解作用及混合微生物的同化作用下被去除。 紫外—微臭氧工艺深度处理含MC的饮用水，HRT为1.5h时，MC-RR、MC-YR与MC-LR的降解效率分别为61.9％、81.9％和91.7％，降解过程为一级动力学反应，半降解时间t_1／2分别为74.5、32.2和24.2min。连续流运行时，MC-RR、MC-YR、MC-LR的平均去除率分别为39.8％、62.7％和74.0％。紫外辐射与较高的臭氧投加量促进MC的降解。 生物活性炭工艺深度处理含MC的饮用水，HRT为1.5h时，MC-RR、MC-YR、MC-LR的去除率分别为60.6％、63.3％和68.8％，去除途径为微生物直接降解与活性炭吸附后再被微生物降解。 阶式生物接触氧化—混凝沉淀—砂滤—加氯消毒组合净水工艺对COD_Mn、UV₂₅₄、氨氮、总MC的去除率分别为70.2％、27.9％、84.5％和88.0％，GC／MS分析表明有机物种类和总量的去除率分别为29.8％和90.7％。混凝沉淀—砂滤—生物活性炭—加氯消毒组合净水工艺对COD_Mn、UV₂₅₄、氨氮、总MC的去除率分别为78.9％、43.6％、79.2％和84.9％，有机物种类和总量的去除率分别为65.9％和97.4％。混凝沉淀—砂滤—加氯消毒—紫外-微臭氧组合净水工艺对COD_Mn、UV₂₅₄、氨氮、总MC的去除率分别为74.1％、50.0％、58.3％和76.9％，有机物种类和总量的去除率分别为64.9％和97.3％。 研究结果表明，阶式生物接触氧化、紫外-微臭氧、生物活性炭工艺均能有河海大学博士学位论文（摘要）效去除饮用水中MC，3种组合净水工艺可用于从富营养化原水制取安全饮用水。更多还原

【Abstract】 Microcystins (MC) are hepatotoxins containing cyclic heptapeptides. Microcystin-LR (MC-LR) is a strongly liver tumour promotor. MC are chemically stable in water and can’t be effectively removed by conventional water treatment processes. The water treatment processes for removing MC from drinking water must be studied urgently. The enzyme-linked immunosorbent assay (ELISA) and high performance liquid chro-matography (HPLC) analysis for detection of MC were optimized. The removal rates of MC by conventional water treatment processes were investigated through the laboratory study and the detection of MC in every process in Meiyuan Drinking Water Treatment Plant. Results showed that the prechlorination of eutrophic water led to the release of intracellular toxins to water phase. The extracellular MC had no change in coagulation sedimentation process. 17.2%~40.4% of extracellular MC and 19.0%-36.6% of total MC were removed by filtration. 30%~45.3% of extracellular MC and 30%~51.7% of total MC were removed by chlorination.Cascade biological contact oxidation reactor was more effective and stable for the treatment of eutrophic water than one-step reactor. The removal rates of NH3-N, NO2- -N and CODmn in the cascade biofilm reactor were higher than those in conventional water treatment processes. When HRT was 2 hours, more than 90% of NH3-N, NO2--N , turbidity value and algaes were removed , more than 20% of CODmn was removed. Meanwhile, the removal rates of extracellular MC, MC-RR and MC-LR reached over 85%, 81.7% and 86.7%, respectively, and the removal rates of total MC, MC-RR and MC-LR reached over 84%, 80.5% and 71.5%, respectively. When the ratios of gas to water of three steps were 2:1, 0.5-1:1 and 0-0.5:1, respectively, pollutants were removed effectively from water. In the biological pretreatment procedure for eutrophic water, MC were degraded by special bacteria and assimilated by heterotrophic microorganisms.When drinking water containing MC was advanced treated by the ultraviolet/micro-ozone (UV/microO3) process, 61.9% of MC-RR, 81.9% of MC-YR and 91.7% of MC-LR were removed within 1.5 hours. The photochemical degradation was characterized by pseudo-first order reaction kinetics. The reaction half lives (t1/2) for MC-RR, MC-YR and MC-LR were 74.5 min, 32.2 min and 24.2min, respectively. When the laboratory-scale photochemical reactor ran continuously, the average degradation rates for MC-RR, MC-YR and MC-LR were 39.8%, 62. 7% and 74.0%, respectively. Ultraviolet radiation and ozone in high doses accelerated the degradationof MC.The biological activated carbon (BAC) process was used for the advanced treatment for drinking water containing MC. 60.6% of MC-RR, 63.3% of MC-YR and 68.8% of MC-LR were removed within 1.5 hours. In this process MC were removed by two paths, one was MC degraded directly by microorganisms and the other was MC degraded by microorganisms after adsorbed by active carbon.In cascade biological contact oxidation with flocculation, sand filtration and chlorina-tion procedures, the removal rates of CODmn, UV254, NH3-N and total MC were 70.2%, 27.9%, 84.5% and 88.0%, respectively. The kind and quantity of organic substances were reduced by 29.8% and 90.7%, respectively, determined by GC/MS analysis. In flocculation with sand filtration, BAC and chlorination procedures, the removal rates of CODMn, UV254, NH3-N and total MC were 78.9%, 43.6%, 79.2% and 84.9%, respectively. The kind and quantity of organic substances were reduced by 65.9% and 97.4%, respectively. In flocculation with sand filtration, chlorination and UV/microO3 procedures, the removal rates of CODmn, UV254, NH3-N and total MC were 74.1%, 50.0%, 58.3% and 76.9%, respectively. The kind and quantity of organic substances were reduced by 64.9% and 97.3%, respectively.MC reduced obviously in cascade biological contact oxidation, UV/microO3 and BAC processes. The three combination water treatment processes referred in above paragraph could be used for the treatment of safe drinking water from eutrophic water.更多还原