With the rapid development of society, industrialization and urbanization, environmental problems have become increasingly prominent, among which water pollution has become one of the important factors restricting sustainable development. In order to meet this challenge, governments and enterprises all over the world have strengthened their investment and management in environmental protection, especially formulated a series of scientific and reasonable measures and standards in sewage treatment. This paper will discuss the importance of sewage treatment in environmental protection setting and its main setting contents.

First, the significance of sewage treatment

1. Protect public health: Untreated or improperly treated domestic sewage and industrial wastewater contain a lot of harmful substances, and direct discharge into natural waters will not only destroy the ecological balance, but also affect human health through the food chain.

2. Restore ecosystem function: Reasonable and effective sewage treatment can reduce the diffusion of pollutants into the environment, help restore the function of damaged water bodies and protect biodiversity.

3. Realize resource recycling: Modern sewage treatment technology can recover valuable resources such as nitrogen and phosphorus and renewable energy (such as methane) from wastewater, and promote the reuse of resources.

Second, the main settings of sewage treatment

1. Pre-treatment stage: It includes the initial purification steps such as removing large impurities by grid and settling suspended matters in grit chamber, which creates favorable conditions for the subsequent process.

2. Biochemical treatment unit: The indicators such as dissolved COD (chemical oxygen demand) and BOD (biochemical oxygen demand) are removed by microbial degradation methods such as activated sludge method and biofilm method.

3. Advanced treatment and disinfection: advanced oxidation, filtration and adsorption are adopted to further purify micro-pollutants that are difficult to be decomposed biochemically; At the same time, chlorine or other disinfectants are added to kill pathogenic bacteria to ensure the safety of effluent.

4. Reuse and emission control: according to different uses, select appropriate reuse water quality standards for advanced treatment for urban greening irrigation, industrial cooling, etc.; For the tail water discharged directly into rivers, lakes and seas, it must reach the discharge limit stipulated by the state.

Third, the conclusion

To sum up, attaching importance to and improving the sewage treatment system in environmental protection setting is an inevitable requirement for maintaining the quality of ecological environment and realizing long-term economic and social development. Facing the new challenges brought by global climate change, we should continue to optimize and upgrade existing facilities and technologies, promote the formation of a new sewage treatment model with high efficiency, energy saving, low carbon and environmental protection, and jointly protect every clear water source on this blue planet.