Sewage treatment in accordance with its role can be divided into physical, biological and chemical three.
① physical method: the main use of physical separation of wastewater non-soluble substances, in the process does not change the chemical properties. Commonly used gravity separation, centrifugal separation, reverse osmosis, flotation and so on. Physical treatment of structures is relatively simple and economical, for the village water capacity, self-purification ability, sewage treatment requirements of the situation is not high.
② biological method: the use of microbial metabolism, the sewage was dissolved or colloidal organic matter decomposition oxidation of stable inorganic substances, so that the sewage purification. Commonly used activated sludge and biofilm method. Biological method to deal with higher than the physical method.
③ chemical method: the use of chemical reactions to treat or recycle wastewater dissolved substances or colloidal substances, used for industrial wastewater. Commonly used coagulation, neutralization, redox, ion exchange and so on. Chemical treatment method has the advantages of good treatment effect and high cost, and is used as the effluent after biochemical treatment for further treatment to improve effluent quality.
Industrial wastewater treatment methods
A method for treating industrial sewage belongs to the technical field of sewage treatment. Which leads the sewage to the sump, adjusts the pH of the sump at the end of the sump, promotes the first pressure dissolving tank with the first dissolving water pump, and sucks the air and condenses the bleaching agent at the same time, Within a saturated dissolved water suddenly released into a flotation tank to form a treated water; a treated water spilled into the buffer tank, and then control the pH with two dissolved gas pump to raise the primary treatment water to two pressure Dissolved gas tank, while inhaling air and coagulation decolorizing agent, the second pressure dissolved gas tank in the second stage saturated dissolved gas suddenly released into the secondary flotation tank to form secondary treated water and overflow to the sedimentation tank after the discharge ; One, two floating flotation tank into the floating mud pool, filter press into the filter cake, the filtrate back to the catchment. The CODcr, decolorization rate, removal rate of SS and BOD5 of the industrial sewage treated by the method are respectively 80-90%, 95%, 90% and 75-80%, and are in line with the primary water discharge standard of GB8978-1996. Biogas power generation is a new energy comprehensive utilization technology integrating environmental protection and energy saving. It utilizes the biogas produced by anaerobic fermentation of industrial sewage to drive the power generation of biogas generating sets and can make full use of the waste heat of the generating sets for biogas production so that the overall thermal efficiency reaches about 80%, which is much higher than the 30% to 40% Efficiency, the user's economic efficiency is obviously a good way to deal with industrial wastewater.