Second, the water treatment methods Papermaking industrial wastewater treatment should focus on improving the circulating water rate, reduce water consumption and waste water emissions, but also should actively explore a variety of reliable, economical and able to make full use of useful resources in wastewater treatment. For example, the flotation method can recover the fibrous solid material in white water, the recovery rate can reach 95%, clarified water can be reused; combustion method can be recovered in black water sodium hydroxide, sodium sulfide, sodium sulfate and other organic salts combined with other sodium. Neutralization method to adjust the pH value of wastewater; coagulation sedimentation or flotation method can remove suspended solids in wastewater; chemical precipitation method can be decolorized; biological treatment can remove BOD, kerosene wastewater is more effective; wet oxidation treatment of sulfite pulp wastewater success. In addition, domestic and foreign also use reverse osmosis, ultrafiltration, electrodialysis and other treatment methods.
Food industry wastewater treatment First, the composition of the food industry Wastewater contaminants Food industry wastewater is characterized by high levels of organic matter and suspended solids, easy to corruption, generally no major toxicity. The harm is mainly to make the water eutrophication, resulting in aquatic animals and fish death, to promote the formation of organic matter underwater odor, deterioration of water quality, pollution of the environment. Second, the water treatment method of food industry wastewater treatment in addition to water quality characteristics of the appropriate pre-treatment, the general should be used biological treatment. Such as the water quality requirements for high or because of high levels of organic matter in wastewater, can be used two-stage aeration tank or two bio-filter, or multi-level biological turntable. Or in combination with two biological treatment devices, can also be used anaerobic - aerobic series of biological treatment system.