Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·...Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·Mg2+ or HCO3--Mg2+·Ca2+; SO42--Ca2+ and SO42--Ca2+·Mg2+; Cl--Ca2+; and CO32--Na+. The deteriorations of groundwater quality due to the increase of TDS, NO3-+ NO2-(as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl-and NO3-ions and weak negative correlations between the depth of water table and Ca2+, SO42-, Cl-and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2-and Mn2+ ions.展开更多
Circumstance influence factors on Hybrid Membrane Bio-Reactor (HMBR) process for the wastewater reclamation in dwelling district was analyzed. The main characteristic of this process is that sludge and nitrified efflu...Circumstance influence factors on Hybrid Membrane Bio-Reactor (HMBR) process for the wastewater reclamation in dwelling district was analyzed. The main characteristic of this process is that sludge and nitrified effluent can be recycled automatically, which simplifies the operation of system and is beneficial to get the high removal of organics and nitrogen. Based on the analysis of circumstance influence factors, it is recommended that water temperature of about 20℃, influent pH of 6 -7 and DO of 1. 0 mg/L - 1. 5 mg/L in the aerobic compartment. Under these conditions, COD, BOD5, NH4+ -N, and TN were removed effectively in HMBR and the average removal efficiencies were 94.5%, 99.3%, 99.4% and 84.7%, respectively. SS and coliforms were both below the detection limits in the permeate of UF membrane module, and turbidity was less than 1NTU. The treated effluent meets the Miscellaneous Domestic Water Quality Standard (CJ25.1-89), and can be reused multipurposely such as watering of green belts, cleaning and toilet flushing water after disinfection.展开更多
An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the tre...An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the treatment process was chosen by building a cost-benefit model; and the modeling test was performed about the operation effect of the proposed project and the recommended water quality of reclaimed water. It is estimated that 3.4×10^5 m^3/a tap water and 6.1×10^5 Yuan/a will be saved if the project was put into operation and the proposed project will reduce the total quantity of pollutant efficiently and bring lots of social and economic benefits.展开更多
文摘Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·Mg2+ or HCO3--Mg2+·Ca2+; SO42--Ca2+ and SO42--Ca2+·Mg2+; Cl--Ca2+; and CO32--Na+. The deteriorations of groundwater quality due to the increase of TDS, NO3-+ NO2-(as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl-and NO3-ions and weak negative correlations between the depth of water table and Ca2+, SO42-, Cl-and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2-and Mn2+ ions.
文摘Circumstance influence factors on Hybrid Membrane Bio-Reactor (HMBR) process for the wastewater reclamation in dwelling district was analyzed. The main characteristic of this process is that sludge and nitrified effluent can be recycled automatically, which simplifies the operation of system and is beneficial to get the high removal of organics and nitrogen. Based on the analysis of circumstance influence factors, it is recommended that water temperature of about 20℃, influent pH of 6 -7 and DO of 1. 0 mg/L - 1. 5 mg/L in the aerobic compartment. Under these conditions, COD, BOD5, NH4+ -N, and TN were removed effectively in HMBR and the average removal efficiencies were 94.5%, 99.3%, 99.4% and 84.7%, respectively. SS and coliforms were both below the detection limits in the permeate of UF membrane module, and turbidity was less than 1NTU. The treated effluent meets the Miscellaneous Domestic Water Quality Standard (CJ25.1-89), and can be reused multipurposely such as watering of green belts, cleaning and toilet flushing water after disinfection.
文摘An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the treatment process was chosen by building a cost-benefit model; and the modeling test was performed about the operation effect of the proposed project and the recommended water quality of reclaimed water. It is estimated that 3.4×10^5 m^3/a tap water and 6.1×10^5 Yuan/a will be saved if the project was put into operation and the proposed project will reduce the total quantity of pollutant efficiently and bring lots of social and economic benefits.
