A study was carded out at the Loess Plateau in Dongzhi, China, to test the feasibility of using secondary treatment sewage effluent and to determine whether the water quality would then meet the recommended irrigation...A study was carded out at the Loess Plateau in Dongzhi, China, to test the feasibility of using secondary treatment sewage effluent and to determine whether the water quality would then meet the recommended irrigation norm. Seven crops, including celery, wheat, maize, millet, apples, rapeseed and yellow beans, were tested in the study. Physical and chemical properties of the soil, crop yield and quality and leachate at different soil depths were measured. In most cases, the quality of the crops that made use of treated sewage was not distinctively different from those that did not use treated sewage. However, yields for the former were much higher than they were for the latter. Leachates at different soil depths were analyzed and the results did not show alarming levels of constituents. For a period of approximately 14 months, the treated sewage irrigation had no significant effect on the loess soil and no cases of illness resulting from contact with the treated sewage were reported. With treated sewage irrigation, a slight increase in the organic content of the soil was observed.展开更多
In June, 2004 and February, 2007, in field tracer studies were conducted on the Hollywood and South Central outfalls, using sulfur hexafluoride (SF6) as a tracer. The objective of these studies was to determine if the...In June, 2004 and February, 2007, in field tracer studies were conducted on the Hollywood and South Central outfalls, using sulfur hexafluoride (SF6) as a tracer. The objective of these studies was to determine if the tracer could be detected in the farfield at significant distance, and if so, could this data be used to construct a model of the farfield plume. Prior models for farfield plume movement do not appear to comport well with the conditions in southeast Florida. Extensive research was conducted in southeast Florida on 4 outfalls, which led to the development of nearfield dilution equations for same. However farfield modeling of outfall plumes was difficult to accomplish because the tracers used are not detectable for significant distances. The SF6 resolved that problem and as a result the Hollywood outfall was used to construct a model. Two methods were investigated for modeling the plume, 1) the Eureqa formulation method and 2) the Gamma-Curve method. The concentrations in the x-y plane were first found by using the Eureqa formulation to calculate the concentration at each grid point given its depth and the concentration of the centerline at the same latitude. The plume models were generated using MATLAB that matched with the results actually seen in the field.展开更多
Intensive agriculture activities,industrialization and growing numbers of wastewater treatment plants along river banks collectively contribute to the elevated levels of neurotoxic pollutants in natural water reservoi...Intensive agriculture activities,industrialization and growing numbers of wastewater treatment plants along river banks collectively contribute to the elevated levels of neurotoxic pollutants in natural water reservoirs across Europe.We established an in vitro bioassay based upon neural stem cells isolated from the subventricular zone of the postnatal mouse to evaluate the neurotoxic potential of raw wastewater,treated sewage effluent,groundwater and drinking water.The toxic potential of water samples was evaluated employing viability,proliferation,differentiation and migration assays.We found that raw wastewater could reduce the viability and proliferation of neural stem cells,and decreased the neuronal and astrocyte differentiation,neuronal neurite growth,astrocyte growth and cell migration.Treated sewage water also showed inhibitory effects on cell proliferation and migration.Our results indicated that relatively high concentrations of nitrogenous substances,pesticides,mercuric compounds,bisphenol-A,and phthalates,along with some other pollutants in raw wastewater and treated sewage water,might be the reason for the neuroinhibitory effects of these water samples.Our model successfully predicted the neurotoxicity of water samples collected from different sources and also revealed that the incomplete removal of contaminants from wastewater can be problematic for the developing nervous system.The presented data also provides strong evidence that more effective treatments should be used to minimize the contamination of water before release into major water bodies which may be considered as water reservoirs for human usage in the future.展开更多
Experiments were conducted on the survival rate of fecal coliform after spreading the sewage sludge for desiccation on sludge beds in an open field throughout the year. The ambient temperature, humidity, sunlight inte...Experiments were conducted on the survival rate of fecal coliform after spreading the sewage sludge for desiccation on sludge beds in an open field throughout the year. The ambient temperature, humidity, sunlight intensity and solar radiation were measured during the period of sludge desiccation. The maximum average temperature, sunlight intensity and solar radiation were recorded throughout the year. During May and August the minimum microbial counts were recorded after four weeks of sludge desiccation. Relative humidity did not have significant effect on survival rate. The minimum microbial counts were taken after four weeks of sludge drying. When the sludge was mixed with three different media, the maximum count of fecal coliform was presented when soil mixed with sludge and irrigated with treated sewage effluent (TSE). When soil mixed with sludge irrigated with well water, the number of fecal coliform count dropped significantly. The minimum count occurred when compost was used instead of sludge. This was a clear indication that the source of contamination was from sludge and was mostly contributed by the TSE irrigation. The use of dried sludge after four weeks of treatment had the lowest fecal coliform count and was safe to be used as fertilizer for farming. Oman is located in a semi-equatorial belt with arid environmental conditions which are ideal for elimination of microbial pathogens. Thus, sludge desiccation in such environmental conditions, specifically during the hot months of the year, is perfect for such practice.展开更多
基金Project supported by the NSFC Innovation Team Project(No. 40421101)the Hundred Talent Scholar Foundation, Chinese Academy of Sciences(2004)the Tackling-Key Scientific and Technical Program Foudation of Gansu Province (No. JS002-A52-020).
文摘A study was carded out at the Loess Plateau in Dongzhi, China, to test the feasibility of using secondary treatment sewage effluent and to determine whether the water quality would then meet the recommended irrigation norm. Seven crops, including celery, wheat, maize, millet, apples, rapeseed and yellow beans, were tested in the study. Physical and chemical properties of the soil, crop yield and quality and leachate at different soil depths were measured. In most cases, the quality of the crops that made use of treated sewage was not distinctively different from those that did not use treated sewage. However, yields for the former were much higher than they were for the latter. Leachates at different soil depths were analyzed and the results did not show alarming levels of constituents. For a period of approximately 14 months, the treated sewage irrigation had no significant effect on the loess soil and no cases of illness resulting from contact with the treated sewage were reported. With treated sewage irrigation, a slight increase in the organic content of the soil was observed.
文摘In June, 2004 and February, 2007, in field tracer studies were conducted on the Hollywood and South Central outfalls, using sulfur hexafluoride (SF6) as a tracer. The objective of these studies was to determine if the tracer could be detected in the farfield at significant distance, and if so, could this data be used to construct a model of the farfield plume. Prior models for farfield plume movement do not appear to comport well with the conditions in southeast Florida. Extensive research was conducted in southeast Florida on 4 outfalls, which led to the development of nearfield dilution equations for same. However farfield modeling of outfall plumes was difficult to accomplish because the tracers used are not detectable for significant distances. The SF6 resolved that problem and as a result the Hollywood outfall was used to construct a model. Two methods were investigated for modeling the plume, 1) the Eureqa formulation method and 2) the Gamma-Curve method. The concentrations in the x-y plane were first found by using the Eureqa formulation to calculate the concentration at each grid point given its depth and the concentration of the centerline at the same latitude. The plume models were generated using MATLAB that matched with the results actually seen in the field.
基金the Higher Education Commission(HEC),Pakistan(Ref.PD/OS-II/Batch-VI/Germany/2015/77159/17755)the University of Applied Sciences Kaiserslautern,Germany for providing financial support to execute the present project。
文摘Intensive agriculture activities,industrialization and growing numbers of wastewater treatment plants along river banks collectively contribute to the elevated levels of neurotoxic pollutants in natural water reservoirs across Europe.We established an in vitro bioassay based upon neural stem cells isolated from the subventricular zone of the postnatal mouse to evaluate the neurotoxic potential of raw wastewater,treated sewage effluent,groundwater and drinking water.The toxic potential of water samples was evaluated employing viability,proliferation,differentiation and migration assays.We found that raw wastewater could reduce the viability and proliferation of neural stem cells,and decreased the neuronal and astrocyte differentiation,neuronal neurite growth,astrocyte growth and cell migration.Treated sewage water also showed inhibitory effects on cell proliferation and migration.Our results indicated that relatively high concentrations of nitrogenous substances,pesticides,mercuric compounds,bisphenol-A,and phthalates,along with some other pollutants in raw wastewater and treated sewage water,might be the reason for the neuroinhibitory effects of these water samples.Our model successfully predicted the neurotoxicity of water samples collected from different sources and also revealed that the incomplete removal of contaminants from wastewater can be problematic for the developing nervous system.The presented data also provides strong evidence that more effective treatments should be used to minimize the contamination of water before release into major water bodies which may be considered as water reservoirs for human usage in the future.
文摘以污水厂处理水为研究对象,采用铁基质生物载体与生物膜耦合实现高效自养反硝化脱氮。考察停留时间(HRT)对系统脱氮效能的影响,通过动力学及微生物群落结构分析,揭示耦合技术的脱氮机理。结果表明:HRT为8 h,对一级A和一级B污水厂处理水,总氮(TN)平均去除率分别为95.41%和92.55%,TN处理负荷分别为0.48 kg TN/(m^3·d)和0.58 kg TN/(m^3·d),硝化过程氨氮(NH4^+-N)饱和常数分别为1.17 mg/L和0.72 mg/L,反硝化过程硝氮(NO3^--N)饱和常数分别为0.87 mg/L和0.67 mg/L。出水水质分别达到《地表水环境质量标准》Ⅲ类、Ⅴ类水质标准。铁基质生物载体与生物膜耦合系统中微生物优势菌属为Maritimimonas、Rhodobacter和Sphaerotilus,均为自养反硝化菌,证实了铁基质生物载体可为自养反硝化菌提供电子,实现生物自养反硝化脱氮。
文摘Experiments were conducted on the survival rate of fecal coliform after spreading the sewage sludge for desiccation on sludge beds in an open field throughout the year. The ambient temperature, humidity, sunlight intensity and solar radiation were measured during the period of sludge desiccation. The maximum average temperature, sunlight intensity and solar radiation were recorded throughout the year. During May and August the minimum microbial counts were recorded after four weeks of sludge desiccation. Relative humidity did not have significant effect on survival rate. The minimum microbial counts were taken after four weeks of sludge drying. When the sludge was mixed with three different media, the maximum count of fecal coliform was presented when soil mixed with sludge and irrigated with treated sewage effluent (TSE). When soil mixed with sludge irrigated with well water, the number of fecal coliform count dropped significantly. The minimum count occurred when compost was used instead of sludge. This was a clear indication that the source of contamination was from sludge and was mostly contributed by the TSE irrigation. The use of dried sludge after four weeks of treatment had the lowest fecal coliform count and was safe to be used as fertilizer for farming. Oman is located in a semi-equatorial belt with arid environmental conditions which are ideal for elimination of microbial pathogens. Thus, sludge desiccation in such environmental conditions, specifically during the hot months of the year, is perfect for such practice.
