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
Although Dahongshan Copper Mine, a subsidiary of Chinalco Co., Ltd., has a large production scale, it is still a non-ferrous metal underground mine with low mechanization and labor efficiency due to its early producti...Although Dahongshan Copper Mine, a subsidiary of Chinalco Co., Ltd., has a large production scale, it is still a non-ferrous metal underground mine with low mechanization and labor efficiency due to its early production. In recent years, mines have carried out a large number of beneficial scientific explorations and practices on production safety management. According to their own actuality, they have combined production safety with scientific management. They have done meticulously and solidly, ensuring that the safety situation continues to be good. There have been no serious injury accidents, let alone work-related accidents for two consecutive years. The injury rate of thousands of people is in the good results within the control index have also made it a benchmark for safety management in the nonferrous mines of Chinalco. This paper analyzes and discusses the scientific methods and good experiences of the production safety of Dahongshan Copper Mine from six aspects: explosion management, organizational security, infrastructure, safety inspection and quantitative mechanism, safety training, safety science and technology, etc. Finally, it gives suggestions for the next production safety of Dahongshan Copper Mine.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Although Dahongshan Copper Mine, a subsidiary of Chinalco Co., Ltd., has a large production scale, it is still a non-ferrous metal underground mine with low mechanization and labor efficiency due to its early production. In recent years, mines have carried out a large number of beneficial scientific explorations and practices on production safety management. According to their own actuality, they have combined production safety with scientific management. They have done meticulously and solidly, ensuring that the safety situation continues to be good. There have been no serious injury accidents, let alone work-related accidents for two consecutive years. The injury rate of thousands of people is in the good results within the control index have also made it a benchmark for safety management in the nonferrous mines of Chinalco. This paper analyzes and discusses the scientific methods and good experiences of the production safety of Dahongshan Copper Mine from six aspects: explosion management, organizational security, infrastructure, safety inspection and quantitative mechanism, safety training, safety science and technology, etc. Finally, it gives suggestions for the next production safety of Dahongshan Copper Mine.