水是国家宝贵的资源之一。随着工农业发展和人口的增长,工业与生活用水量也不断上升,供需矛盾、水源不足,已成为目前全国性的现象,加以各种废水和污水排放量日益巨增,不仅浪费了水利资源和其他动力资 Water is one of the country’s precious resources. With the development of industry and agriculture and the increase of population, the water consumption in industry and in life is also rising. The contradiction between supply and demand and the shortage of water sources have become a national phenomenon. Increasing the amount of various waste water and sewage discharges is increasing, which not only wastes water resources and Other power resources