Author: Site Editor Publish Time: 2023-09-14 Origin: Site
Sewage collection and disposal refers to the collection of sewage generated in cities, industries, rural areas and other areas through pipelines or other means, and through a series of physical, chemical, biological and other treatment processes, the pollutants in it are removed or transformed to achieve Discharge into water bodies or reuse after meeting national discharge standards.
The first step in sewage disposal is to collect sewage, and collect sewage generated in cities, industries, and rural areas through sewers or sewage pipes. Usually the following methods are used:
1.1 Drain pipes: Urban and industrial areas often use drain pipes to collect sewage. These pipes are usually buried underground and carry sewage from buildings and roads to sewage disposal plant.
1.2 Centralized collection system: In some rural and remote areas, there may be no drainage pipes. In this case, a centralized collection system can be used, that is, a centralized collection and treatment system is established to collect sewage from the surrounding area and transport it to a sewage wastewater treatment plant.
1.3 Decentralized collection system: In some remote areas or in individual buildings, it may not be convenient to use a centralized collection system. In this case, a decentralized collection system can be used, that is, an independent sewage disposal system is established in each building or community, and the treated sewage is used for irrigation or flushing.
1.4 Rainwater collection system: In some cities and buildings, rainwater collection systems can be used to collect rainwater and use it for flushing and irrigation. This reduces the need for mains water while reducing the load on drain pipes.
The above are the commonly used collection methods for sewage water disposal. According to different regions and needs, different collection methods can be selected.
2.1 Grille: Pretreatment includes machanical fine bar screen and rotary drum fine screen. Use a grille to intercept large particles such as paper, cloth, branches, leaves, plastic bags, etc. in the sewage to prevent them from causing damage to downstream processing equipment.
2.2 Grit chamber: Put sewage into a grit chamber to allow sediment to sink to the bottom. Then the clear water in the upper layer is discharged to remove the sediment, thereby removing the sediment in the sewage.
Although primary treatment only removes large particles and sediments in sewage, it is very important for subsequent secondary and advanced treatment. If the primary treatment is not thorough, the downstream treatment equipment and treatment effect will be affected, and even increase the difficulty and wastewater treatment cost. Therefore, primary treatment is an integral step in the wastewater treatment process.
The suspended solids, organic matter and nutrients in the sewage are removed by biological treatment methods such as biological contact oxidation tanks and activated sludge methods to reduce the impact on nature. pollution of the environment.
3.1 Activated sludge method: Activated sludge is used to biodegrade and adsorb organic matter in water to remove organic matter and nutrients such as nitrogen and phosphorus in sewage.
3.2 Membrane separation method: use microporous membranes for filtration and separation to remove suspended solids, organic matter and nutrients in sewage.
After the secondary treatment, the water quality of the sewage will be significantly improved, which can meet the discharge standards stipulated by the state, thereby reducing the pollution to the environment.
The advanced treatment of sewage disposal treatment mainly refers to the further removal of microorganisms and other harmful substances in sewage through deep filtration and ultraviolet sterilization on the basis of primary and intermediate treatment, and to improve the quality of effluent water to achieve higher discharge Standard or direct reuse.
4.1 Biofilm Reactor (mbr system): Use microorganisms to remove organic substances, nitrogen, phosphorus and other pollutants, and remove suspended solids and bacteria through membrane filtration technology, and the effluent quality reaches the national first-class A standard.
4.2 Reverse Osmosis (ro system): Use semi-permeable membrane filtration technology to remove dissolved ions, organic substances and microorganisms in water, and the effluent quality can reach the national first-class A standard.
4.3 Ultraviolet disinfection: use ultraviolet rays to kill microorganisms in the water, and the quality of the effluent water can reach the national secondary A standard.
Sewage treatment and disposal effluent discharge refers to the process in which the treated water is discharged into the natural environment. According to national standards and local policies, the discharge of effluent wastewater treatment needs to meet certain water quality standards and discharge standards, and at the same time, reasonable discharge and utilization should be carried out according to the local environment and water resource conditions.
The importance of wastewater collection and treatment lies in protecting water resources, improving the environment, promoting economic development and safeguarding people's health.