The main municipal sewage is used in a variety of detergents and sewage, garbage, feces and other, mostly non-toxic inorganic salts, sewage in nitrogen, phosphorus, sulfur and more and more disease-causing bacteria.

Pathogen contamination

Mainly from municipal sewage, hospital sewage, garbage and other aspects of surface runoff. Pathogenic microorganisms is characterized by: a large number ①; ② widely distributed; ③ survive longer; ④ propagation speed; ⑤ easy to produce resistance, it is difficult to destroy; ⑥ conventional secondary biological wastewater treatment and chlorination after a some pathogenic microorganisms, viruses still a lot of survival; in fact, these pollutants enter the body through a variety of ways, and to survive in the body, causing human disease.