Adsorption (including ion exchange)

Waste water is passed through a solid adsorbent, so that organic or inorganic substances dissolved in the waste water can be adsorbed on the adsorbent, and the passed waste water can be treated

Adsorbents include adsorption towers such as activated carbon, coal cinder and soil, and regeneration devices

Dyeing and pigment waste water can also adsorb phenol, mercury, chromium and cyanide, as well as decolorization, odor and taste for advanced treatment. Edit this sewage treatment process

Modern sewage treatment technology can be divided into primary, secondary and tertiary treatment according to the degree of treatment.

Primary treatment 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 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 standards.

Three-stage treatment, further treatment of refractory organic matter, soluble inorganic matter such as nitrogen and phosphorus, which can lead to water eutrophication. The main methods include biological nitrogen and phosphorus removal, coagulation and precipitation, sand filtration, activated carbon adsorption, ion exchange and electroosmosis analysis.

The whole process is that the raw sewage passing through the coarse grid is lifted by the sewage lifting pump, passes through the grid or sand filter, and then enters the grit chamber, and the sewage separated from sand and water enters the primary sedimentation tank, which is the primary treatment (i.e. physical treatment), and the effluent from the primary sedimentation tank enters the biological treatment equipment, including the activated sludge method and the biofilm method. Biofilm method includes biological filter, biological rotary table, biological contact oxidation method and biological fluidized bed). The effluent from biological treatment equipment enters the secondary sedimentation tank, and the effluent from the secondary sedimentation tank is disinfected and discharged or enters the tertiary treatment. The primary treatment ends here as secondary treatment, and the tertiary treatment includes biological nitrogen and phosphorus removal method, coagulation sedimentation method, sand filtration method, activated carbon adsorption method, ion exchange method and electrodialysis method. Part of the sludge in the secondary sedimentation tank flows back to the primary sedimentation tank or biological treatment equipment, and part of it enters the sludge concentration tank, and then enters the sludge digestion tank. After dehydration and drying equipment, the sludge is finally utilized.