目前生活垃圾、工业生产会产生大量的污水,城镇污水处理厂的工作任务也越来越艰巨,我国的经济水平在不断提高,促进污水处理厂的提标改造。基于此,本文研究城镇污水处理厂现状,分析城镇污水处理厂一级 A 提标改造工艺策略,从工艺要求、...目前生活垃圾、工业生产会产生大量的污水,城镇污水处理厂的工作任务也越来越艰巨,我国的经济水平在不断提高,促进污水处理厂的提标改造。基于此,本文研究城镇污水处理厂现状,分析城镇污水处理厂一级 A 提标改造工艺策略,从工艺要求、过滤单元、COD、BOD、TP 等方面入手进行总结,从而更好满足人们日益增长的环境需求。展开更多
Inoculating soil with an adapted microbial community is a more effective bioaugmentation approach than inoculation with pure strains in bioremediation.However,information on the potential of different inocula from sit...Inoculating soil with an adapted microbial community is a more effective bioaugmentation approach than inoculation with pure strains in bioremediation.However,information on the potential of different inocula from sites with varying contamination levels and pollution histories in soil remediation is lacking.The objective of the study was to investigate the potential of adapted microorganisms in soil inocula,with different contamination levels and pollution histories,to degrade 1,2,4-trichlorobenzene (1,2,4-TCB).Three different soils from chlorobenzene-contaminated sites were inoculated into agricultural soils and soil suspension cultures spiked with 1,2,4-TCB.The results showed that 36.52% of the initially applied 1,2,4-TCB was present in the non-inoculated soil,whereas about 19.00% of 1,2,4-TCB was present in the agricultural soils inoculated with contaminated soils after 28 days of incubation.The soils inoculated with adapted microbial biomass (in the soil inocula) showed higher respiration and lower 1,2,4-TCB volatilization than the non-inoculated soils,suggesting the existence of 1,2,4-TCB adapted degraders in the contaminated soils used for inoculation.It was further confirmed in the contaminated soil suspension cultures that the concentration of inorganic chloride ions increased continuously over the entire experimental period.Higher contamination of the inocula led not only to higher degradation potential but also to higher residue formation.However,even inocula of low-level contamination were effective in enhancing the degradation of 1,2,4-TCB.Therefore,applying adapted microorganisms in the form of soil inocula,especially with lower contamination levels,could be an effective and environment-friendly strategy for soil remediation.展开更多
Sediments in many rivers and lakes are subjected to resuspension due to a combination of hydrodynamics. However, the roles of contaminant-contained dissolved and particulate sediments during the resuspension release a...Sediments in many rivers and lakes are subjected to resuspension due to a combination of hydrodynamics. However, the roles of contaminant-contained dissolved and particulate sediments during the resuspension release are rarely studied. This study focuses on the release quantity of contaminants in both water phase and solid phase. Conservative tracer （NaC1） and reactive tracer （Phosphorus） were respectively added to cohesive fine-grained sediments and non-cohesive coarse-grained sediments. A range of typical shear stress was conducted to characterize the time-depended release of contaminants in a laboratory flume. When the sediment started to move, the concentration of contaminant in the overlying water increased with the bed shear stress, but the dissolved contaminants responded faster than the particulate ones. The observed contaminant release process can be divided into three main stages： the initial two hours fast mixing： the release contribution of pore water could reach up to 75%; the middle 4-6 h adsorption： the partitioning coefficient of contaminant between water phase and solid phase decreased over the time, and the adsorption of contaminates from resuspended sediment dominated the negative release; the last equilibrium stage： the desorption and adsorption reached equilibrium, and the reactive contaminant made an impact on the water quality in the solid phase. The existing formulas to evaluate the release flux are far from practice meaning as the sediment contaminants undergo a very complex release process.展开更多
文摘目前生活垃圾、工业生产会产生大量的污水,城镇污水处理厂的工作任务也越来越艰巨,我国的经济水平在不断提高,促进污水处理厂的提标改造。基于此,本文研究城镇污水处理厂现状,分析城镇污水处理厂一级 A 提标改造工艺策略,从工艺要求、过滤单元、COD、BOD、TP 等方面入手进行总结,从而更好满足人们日益增长的环境需求。
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-EW-QN403)the National Natural Science Foundation of China (Nos. 41030531,4092106,and 20707028)the Jiangsu Provincial Natural Science Foundation of China (No. BK2010608)
文摘Inoculating soil with an adapted microbial community is a more effective bioaugmentation approach than inoculation with pure strains in bioremediation.However,information on the potential of different inocula from sites with varying contamination levels and pollution histories in soil remediation is lacking.The objective of the study was to investigate the potential of adapted microorganisms in soil inocula,with different contamination levels and pollution histories,to degrade 1,2,4-trichlorobenzene (1,2,4-TCB).Three different soils from chlorobenzene-contaminated sites were inoculated into agricultural soils and soil suspension cultures spiked with 1,2,4-TCB.The results showed that 36.52% of the initially applied 1,2,4-TCB was present in the non-inoculated soil,whereas about 19.00% of 1,2,4-TCB was present in the agricultural soils inoculated with contaminated soils after 28 days of incubation.The soils inoculated with adapted microbial biomass (in the soil inocula) showed higher respiration and lower 1,2,4-TCB volatilization than the non-inoculated soils,suggesting the existence of 1,2,4-TCB adapted degraders in the contaminated soils used for inoculation.It was further confirmed in the contaminated soil suspension cultures that the concentration of inorganic chloride ions increased continuously over the entire experimental period.Higher contamination of the inocula led not only to higher degradation potential but also to higher residue formation.However,even inocula of low-level contamination were effective in enhancing the degradation of 1,2,4-TCB.Therefore,applying adapted microorganisms in the form of soil inocula,especially with lower contamination levels,could be an effective and environment-friendly strategy for soil remediation.
基金supported by the National Natural Science Foundation of China(Grant No.10972134)the State Key Program of National Natural Science of China(Grant No.11032007)
文摘Sediments in many rivers and lakes are subjected to resuspension due to a combination of hydrodynamics. However, the roles of contaminant-contained dissolved and particulate sediments during the resuspension release are rarely studied. This study focuses on the release quantity of contaminants in both water phase and solid phase. Conservative tracer （NaC1） and reactive tracer （Phosphorus） were respectively added to cohesive fine-grained sediments and non-cohesive coarse-grained sediments. A range of typical shear stress was conducted to characterize the time-depended release of contaminants in a laboratory flume. When the sediment started to move, the concentration of contaminant in the overlying water increased with the bed shear stress, but the dissolved contaminants responded faster than the particulate ones. The observed contaminant release process can be divided into three main stages： the initial two hours fast mixing： the release contribution of pore water could reach up to 75%; the middle 4-6 h adsorption： the partitioning coefficient of contaminant between water phase and solid phase decreased over the time, and the adsorption of contaminates from resuspended sediment dominated the negative release; the last equilibrium stage： the desorption and adsorption reached equilibrium, and the reactive contaminant made an impact on the water quality in the solid phase. The existing formulas to evaluate the release flux are far from practice meaning as the sediment contaminants undergo a very complex release process.
