Wastewater treatment methods is to use physical, chemical and biological methods to treat wastewater, so as to purify wastewater and reduce pollution, so as to achieve wastewater recovery, reuse and make full use of water resources.

　　Wastewater is mainly divided into domestic wastewater and industrial wastewater.

Wastewater treatment works

　　processing method

　　Physical treatment

　　The methods of physical separation and recovery of undissolved suspended pollutants (including oil film and oil bead) in wastewater can be divided into gravity separation method, centrifugal separation method and screen filtration and retention method. The treatment unit of gravity separation method includes sedimentation, floatation (air flotation), etc. the corresponding treatment equipment is grit chamber, sedimentation chamber, oil separator, air flotation chamber and its accessories. Centrifugal separation is a kind of treatment unit. The treatment devices used include centrifugal separator and water separator. There are two kinds of treatment units for screen filtration, screen filtration and screen filtration. The former uses screen and screen, while the latter uses sand filter and microporous filter. The treatment method based on the principle of heat exchange also belongs to physical treatment method, and its treatment unit includes evaporation, crystallization, etc.

　　One method of removing organic matter from wastewater is activated carbon adsorption. Activated carbon treatment can be used with activated sludge process, in which powdered activated carbon is used. Powdered activated carbon can absorb those substances that are toxic to microorganisms, and finally collect them together with sludge. The main danger of activated carbon in wastewater treatment is that the invalid activated carbon may always exist in water.

　　Chemical treatment

　　A wastewater treatment method which can separate and remove the dissolved and colloidal pollutants or convert them into harmless substances by chemical reaction and mass transfer. In the chemical treatment, the treatment units based on the chemical reaction generated by adding agents are: coagulation, neutralization, oxidation-reduction, etc.; while the treatment units based on mass transfer are: extraction, stripping, blowing off, adsorption, ion exchange, electrodialysis and reverse osmosis, etc. The latter two treatment units are also called membrane separation technology. The treatment unit using mass transfer has both chemical action and physical action related to it, so it can also be separated from chemical treatment method and become another kind of treatment method, which is called physicochemical method.

　　Biological treatment

　　Through the metabolism of microorganisms, the organic pollutants in solution, colloid and micro suspension state are transformed into stable and harmless substances. According to different microorganisms, biological treatment can be divided into aerobic biological treatment and anaerobic biological treatment.

　　Aerobic biological treatment is widely used in wastewater treatment. According to the tradition, aerobic biological treatment is divided into activated sludge method and biofilm method. Activated sludge process itself is a kind of treatment unit, which has a variety of operation modes. The treatment equipment of biofilm process includes biofilter, biological turntable, biological contact oxidation tank and biological fluidized bed, etc. Biological oxidation pond method is also called natural biological treatment method. Anaerobic biological treatment, also known as biological reduction treatment, is mainly used to treat high concentration organic wastewater and sludge. The main treatment equipment used is digestion tank.

　　The biological contact oxidation process is used to treat wastewater, i.e. the biological contact oxidation process is used to fill the bioreactor tank with fillers, and the oxygenated wastewater is immersed in all fillers and flows through the fillers at a certain flow rate. Biofilm is covered on the filler, sewage and biofilm are widely contacted. Under the effect of metabolism of microorganisms on biofilm, organic pollutants in sewage are removed and sewage is purified. Finally, the treated wastewater is discharged into the biological contact oxidation treatment system and mixed with domestic sewage for treatment, and discharged after chlorine disinfection. The biological contact oxidation process is a biofilm process between the activated sludge process and the biological filter. It is characterized by the arrangement of fillers in the tank, aeration at the bottom of the tank to oxygenate the sewage and make the sewage in the tank flow, so as to ensure that the sewage fully contacts the fillers immersed in the sewage and avoid the defects of uneven contact between sewage and fillers in the biological contact oxidation tank This kind of aeration device is called blast aeration.

　　The treatment method of microbial fuel cell is to use the microorganism inoculated in the fuel cell to degrade the toxic substance, organic substance and impurity. Common microbial fuel cells can be divided into: single chamber microbial fuel cell, double chamber microbial fuel cell.

waste water treatment

waste water treatment