Suzhou’s industrialization and urbanization process is relatively rapid, and urban sewage is an unavoidable urban product. Suzhou's sewage pollution is becoming increasingly serious. Improper sewage treatment will restrict the sustainable development of the city's economy. As one of the top five environmental protection companies in Suzhou, Anfeng Environmental Protection also has many successful cases in urban sewage treatment. It uses mechanized treatment, biochemical treatment, sludge treatment, etc. to treat urban sewage. The sewage treatment effect is between first-level and second-level. Generally strengthened first-level agents, first-level and semi-processing or incomplete second-line processing, etc.
Anfeng Environmental Protection classifies the pollutants of sewage, which can be divided into suspended solid pollutants, organic pollutants, toxic substances, polluting organisms, etc. If these substances are discharged into the water body, it will seriously deteriorate the water body. Cause water pollution. Therefore, the process of sewage treatment is very complicated. Anfeng Environmental Protection will give some explanations on the process technology in sewage treatment.
Sewage treatment process technology
The currently popular sewage treatment processes include: AB method, SBR method, oxidation ditch method, ordinary aeration method, membrane separator, etc., each has its own own characteristics.
AB method
This process divides the aeration tank into two levels of oxygen supply according to high and low loads. Grade A has high load, short aeration time, large amount of sludge, sludge load is more than 2.5kgBOD/(kgMLSS?d), tank volume load is more than 6kgBOD/(m3?d); Grade B load is low, sludge Older. Class A and Class B can also be constructed in phases, with an intermediate sedimentation tank between Class A and Class B. The F/M (ratio of pollutant amount to microbial amount) of the two-stage pools is different, forming different microbial groups. Although the AB method has the advantage of energy saving, it is not suitable for low concentration water quality.
SBR method
In this method, water inlet, aeration, sedimentation, and water discharge are completed in the same pool. It usually consists of a group of 3-4 pools, which operate in turn. One pool operates intermittently, so it is called sequential batch activated sludge method. The characteristic of this integrated process is that it is simple. Since there is only one reaction tank, there is no need for a secondary sedimentation tank, return sludge and related equipment. Generally, there is no regulating tank, and in most cases the primary sedimentation tank can be omitted. , so it saves space and investment, is resistant to impact loads and has flexible operation methods. It can arrange different states of aeration, anoxia and anaerobic time to achieve the purpose of phosphorus and denitrification.
Ordinary aeration method
Its variant process, the ordinary aeration method, appeared earliest. Its actual treatment effect is good and it can treat large amounts of sewage. For Jc-r plants, it can be concentrated in construction Sludge digestion tank, the biogas produced can be used as energy. The disadvantage of the traditional general exposure method is that it can only be used as a conventional secondary treatment and does not have the function of nitrogen and phosphorus removal. In recent years, in engineering practice, the purpose of nitrogen removal can be achieved by reducing the volume load of ordinary aeration tanks; phosphorus can be removed by setting up an anaerobic zone in front of ordinary aeration tanks, and chemical methods can also be used to remove phosphorus. The common aeration method is used to remove BOD. There are many forms in the pool type, such as oxidation ditch. In engineering, it is called a variant process of the common aeration method, which can also be collectively referred to as the common aeration method.
The oxidation ditch method
was developed in the early 1950s. Because of its simple structure and easy management, it was quickly promoted and applied, and innovations continued. At present, various forms of oxidation ditch have been developed in application. The more representative ones are: Par type, referred to as single ditch type. Rotating brush aeration is used for surface aeration. The water depth is generally 2.5-3.5m. The Austrian style, referred to as the concentric circle style, is mostly composed of three oval-shaped rings in practical applications. The three rings use different rings. DO, for example, the outer ring is 0, the middle ring is 1, and the inner ring is 2, which is beneficial to nitrogen and phosphorus removal. Rotating disc aeration is used, and the water depth is generally 4.0-4.5m. Cassette type, referred to as circulating baffle type, uses an inverted umbrella-shaped impeller for aeration. The water depth is generally about 3.0m, but sludge is easy to deposit. Three-groove oxidation ditch (T-type oxidation ditch), this process consists of 3 tanks, the middle is an aeration tank, and the two left and right tanks are also used as sedimentation tanks and aeration tanks. It is characterized by the use of rotating brush aeration, shallow water, large area, no anaerobic tank, and no phosphorus removal function.
Membrane separation technology
Using membrane separation instead of sedimentation for mud-water separation can bring about the following changes in the activated sludge process: there is no longer the problem of sludge expansion. When regulating the activated sludge system, it is no longer necessary to consider the settling performance of the sludge, thus greatly simplifying the process control; the sludge concentration in the aeration tank will be greatly increased, and the MLSS can be greater than 20g/L, so that the system can be used in extremely large sludge ages. , operating under ultra-low load conditions, fully meeting the needs of removing various pollutants; under the same treatment requirements, the volume of the aeration tank can be greatly reduced, saving the floor space of the treatment plant; the increase in sludge concentration, A higher aeration rate is required, so pure oxygen aeration will be widely used with membrane separation.
There are many environmental protection companies for sewage treatment in Suzhou, and Anfeng Environmental Protection has an absolute advantage in sewage treatment qualifications. The sewage treatment process is complex and requires relatively high qualifications for environmental protection companies. Sewage treatment is more complex than the wastewater treatment process in enterprises. If you have any questions about sewage treatment, please feel free to call us.