1. Physical method:
Due to high salinity, microbial treatment of high salinity wastewater will be inhibited. The main pollution factors are: PH, SS, COD, NH3-N, TDS, which contain high organic matter and high salinity substances, and the wastewater is mixed wastewater.
2. Chemical method:
It is a method to treat or recover dissolved or colloidal substances in sewage by chemical reaction, which is mostly used in industrial wastewater. Coagulation, neutralization, redox and ion exchange are commonly used. Chemical treatment has good treatment effect and high cost, and it is mostly used as effluent after biochemical treatment for further treatment to improve the effluent quality.
3. Biological method:
Using the metabolic function of microorganisms, the dissolved or colloidal organic substances in sewage are decomposed and oxidized into stable inorganic substances, so that the sewage can be purified. Activated sludge process and biofilm process are commonly used. The treatment degree of biological method is higher than that of physical method.
Extended information:
Treatment technology
Primary treatment:
It mainly removes suspended solid pollutants from sewage, and most physical treatment methods can only meet the requirements of primary treatment. After primary treatment, BOD can generally be removed by about 31%, which can not meet the discharge standard. Primary treatment belongs to the pretreatment of secondary treatment.
secondary treatment:
it mainly removes colloidal and dissolved organic pollutants (BOD, COD) in sewage, and the removal rate can reach over 91%, so that the organic pollutants can meet the discharge standard, and the removal rate of suspended solids can reach 95%, and the effluent effect is good.
tertiary treatment:
further treatment of refractory organic matter, soluble inorganic matter such as nitrogen and phosphorus which can lead to eutrophication of water body. The main methods include biological nitrogen and phosphorus removal, coagulation and precipitation, sand filtration, activated carbon adsorption, ion exchange and electrodialysis.
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