Three-stage water treatment is mainly to remove organic pollutants and dissolved inorganic pollutants that are difficult to biodegrade in wastewater. Commonly used methods are activated carbon adsorption method and ozone oxidation method, can also be used ion exchange and membrane separation technology. A variety of chemical industry wastewater can be based on different water quality, water and after the treatment of external drainage quality requirements, the use of different water treatment methods. Wastewater Treatment in Paper Industry
First, the origin of paper industry Wastewater Papermaking wastewater mainly from papermaking pulp and papermaking two production processes. Pulping is the raw material of the fiber in the separation, made of pulp, and then bleached; paper is the slurry is diluted, molding, pressing, drying, made of paper. Both processes discharge large amounts of waste water. Pulping of waste water, the most serious pollution. Dip off the waste water was dark brown, known as black water, black water pollutant concentration is high, BOD up to 5-40g / L, containing a lot of fiber, inorganic salts and pigments. Bleaching process of waste water also contains a lot of acid and alkali substances. The papermaking machine discharges the waste water, called white water, which contains a lot of fiber and the filler and the compound added during the production process.