【作者】 叶锦韶；

【导师】 尹华；

【作者基本信息】 暨南大学 ， 环境科学， 2003， 硕士

【摘要】 本课题对重金属的生物吸附进行了系统的研究。主要包括生物吸附剂的筛选、吸附性能、吸附工艺、吸附机理、现场试验及毒理实验等。 本研究对多家电镀厂及五金厂进行了重金属废水、污泥采样，微生物分离、筛选、鉴定等工作。共筛选到了十株对铬具有良好吸附性能的菌株：细菌一株、掷孢酵母、产朊假丝酵母、解脂假丝酵母、霉菌六株。 研究了掷孢酵母的培养基成份与配比对吸附铬的影响。最佳培养基配方是：葡萄糖20g／L、蛋白胨5g／L和酵母浸出粉2g／L、pH5。培养60h后，对30mg／L含铬水样的还原率与去除率分别为68.9％、61.6％；味精废水培养的菌体对铬的还原率与去除率分别为68.8％、63.1％。 预处理研究表明NH₄Cl、NH₄NO₃、NaOH、Na₂MoO₄等预处理剂能促进铬的吸附。当NH₄Cl、NH₄NO₃为0.5mol／L时，掷孢酵母对30mg／LCr（VI）的还原率分别为87.1％、84.4％；去除率分别为83.9％、80.7％。吸附液中Na⁺、K⁺、NH4⁺、—NH₂、Cl^-等离子在适当的浓度范围内能促进铬的生物吸附。 吸附pH和培养时间是控制重金属废水生物吸附的重要因素。掷孢酵母、产朊假丝酵母和解脂假丝酵母的适宜pH分别为2.5～6.5、3～5和3～7，适宜培养时间分别是50～65h、35～48h、20～60h。对30～35mg／L Cr（总）的电镀废水的还原率分别达85％～95％、70％～80％、95％～100％；去除率达65％～80％、65％～70％、85％～98％。10g／L掷孢酵母在最佳吸附条件下曝气处理8h后，对Cr（总）34.4mg／L、Cr（VI）30mg／L的电镀废水的还原率与去除率均超过了92％。 处理工艺研究结果表明，在进行鼓风曝气的情况下，生物吸附剂与活性污泥联合应用，能对铬进行有效去除。10g／L的解脂假丝酵母处理30.9～68.6 mg／L Cr（总）电镀废水8h后，去除率达94％～100％，pH 5.4-5.8。对电镀废水的现场实验研究表明，出水含铬低于0.05mg／L，可达标排放。首次提出了重金属废水和无毒高浓度有机废水同步处理的HMOC工艺。毒性实验结果表明，本研究应用的生物吸附剂无害无毒。更多还原

【Abstract】 The biosorption of heavy metal-containing wastewater was studied comprehensively in the research, including selection of biosorbents, capability of sorption, treatment of simulated and practical chromium-containing wastewater, mechanism of biosorption, on-site experiment, and toxicity of chromium and strains of biosorption.Many samples of wastewater and sludge from plating plants and hardware plants were collected. Ten strains cultured by these samples were determined to have high-efficiency of chromium accumulation, including a strain of bacteria, Sporobolomycetaceae sp. YJS, Candida utilis, Candida FOLA, and six strains of mold.The study of culture conditions of biosorbent showed that different ingredients of the medium had distinctive effects on the growth of strains. The optimal cultivation condition of Sporobolomycetaceae sp. YJS was glucose 20g/L, peptone 5g/L, yeast extract 2g/L, and pH5. After cultivated by this medium for 60h, the ceil of S. sp. YJS had reduction and removal ratios of 68.9%, 61.6% to the 30mg/L chromium-containing wastewater after 8hr biosorption. When cultivated by monosodium glutamate wastewater, the ratios were 68.8% ^ 63.1%, respectively.The capability of the biosorbent would be promoted greatly after some rational pretreatments. Among the general compounds, NH4C1, NH4NO3, NaOH, Na2MoO4, especially NH4Cl, NH4NO3, could boost the biosorption effectively. The ratios of reduction were 87.1%, 84.4% respectively, and the removal ratios were 83.9%, 80.7% accordingly, after pretreated the cell by NH4Cl,NH4NO3 severally.There were a lot of ions and compounds in the chromium-containing wastewater, each of them would impact the practice of biosorption accordingly. When ranged from proper concentration, the ions of Na+, K+ , NH4+, -NH2, Cl- would increase the ratios of removal.PH was one of the most crucial factors for the removal of heavy metal by biosorbent. Different strains had dissimilar optimal pH. The appropriate pH of S. sp. YJS, Candida utilis, and Candida FOLA were 2.5-6.5, 3-5, 3-7, the optimal cultivation time were 50~65h, 35~48h, and 20~60h respectively. The reduction and removal ratios to the 30~35mg/Lchromium-containing wastewater by these three strains after 8 hours biosorption were 85%~95%, 65%~80%; 70%~80%, 65%~70%; and 95%~100%, 85%~98% respectively.The efficiency of biosorption would heighten markedly when the suitable conditions for the treatment were reached. When treating plating waste water in which the total content of chromium was 34.4mg/L and the Cr(VI) was 30mg/L, the reduction and removal ratios were exceeded 92% after treated by Sporobolomycetaceae sp. YJS undergoing the optimal condition for 8 hours.The study of aerobic treatment of practical plating wastewater was discussed. The removal ratio to the 30.9-68.6 mg/L chromium-containing wastewater was reached 94%~100% after treated by 10g/L Candida FOLA for 8 hours within the pH range of 5.4-5.8. The combination treatment of heavy metal and organic waste water was proposed for the first time. The toxic experiment showed that the biosorbent were safe.更多还原