In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed...In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.展开更多
Regarding the current difficulties in SME(small and medium enterprise)supervision,especially considering the problem that the emission reduction task cannot be effectively implemented under the off-site daily supervis...Regarding the current difficulties in SME(small and medium enterprise)supervision,especially considering the problem that the emission reduction task cannot be effectively implemented under the off-site daily supervision and the new normal of epidemic prevention with control of heavily polluted weather,a new type of intelligent power management technology has been proposed.Power information collection equipment and intelligent data collection and transmission terminal are installed to collect power consumption information of enterprise production facilities and pollution control facilities,and their operating conditions are monitored in 24 h.Abnormal operation alarm and closed-loop disposal management are provided through the software platform.The practical application of power monitoring technology in Rizhao City proves that the system alarms accurately and monitors efficiently.On the one hand,it has improved the efficiency of daily supervision of the ecological environment department,and can accurately investigate and correct corporate pollution control violations.On the other hand,it has enriched environmental supervision methods to accurately control the implementation of emergency emission reduction measures.The application of this technology has realized the transformation from civil defense to technical defense,from random law enforcement to precise law enforcement,and from on-site law enforcement to off-site law enforcement in the supervision of polluting enterprises in the jurisdiction,creating a new mode of off-site law enforcement for enterprises.展开更多
Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland ...Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.展开更多
文摘In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.
文摘Regarding the current difficulties in SME(small and medium enterprise)supervision,especially considering the problem that the emission reduction task cannot be effectively implemented under the off-site daily supervision and the new normal of epidemic prevention with control of heavily polluted weather,a new type of intelligent power management technology has been proposed.Power information collection equipment and intelligent data collection and transmission terminal are installed to collect power consumption information of enterprise production facilities and pollution control facilities,and their operating conditions are monitored in 24 h.Abnormal operation alarm and closed-loop disposal management are provided through the software platform.The practical application of power monitoring technology in Rizhao City proves that the system alarms accurately and monitors efficiently.On the one hand,it has improved the efficiency of daily supervision of the ecological environment department,and can accurately investigate and correct corporate pollution control violations.On the other hand,it has enriched environmental supervision methods to accurately control the implementation of emergency emission reduction measures.The application of this technology has realized the transformation from civil defense to technical defense,from random law enforcement to precise law enforcement,and from on-site law enforcement to off-site law enforcement in the supervision of polluting enterprises in the jurisdiction,creating a new mode of off-site law enforcement for enterprises.
基金Supported by the National Natural Science Foundation of China (Grant No. 50839002)the "948" Project of the Ministry of Water Resources (Grant No. 200720)
文摘Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.
