Municipal sewage treatment system and equipment built on river

The invention discloses an urban sewage treatment system which is built on rivers and equipment thereof. A trash rack is arranged on the river; then the trash rack is provided with an anaerobic treatment section, an aerobic treatment section, a separation section and a slag discharge section in sequence; clear water is further purified and carried out reoxygenation by a constructed wetland before flowing into a lake or being discharged. The sewage treatment system established by the invention does not take up land and can be built at the end part of the unnavigable river (the inflow river channel of any lake dian can be suitable); the main equipment is arranged at the riverbanks of both sides or on a lifting platform which is set up on a channel and in the river (on the surface of the water and immersing into the water); the treatment technology is the combination of a biological method, a chemical method and the constructed wetland; the treated wastes can generate energy again. The system has the highly savi