Method for reclaiming and utilizing paper-making industrial waste water

Abstract

The invention discloses a wastewater recycling method for paper making industry, and combines membrane technique with industrial water treatment technique. The invention comprises the steps of micro-filtration technique stage, an ultra-filtration technique stage and a reverse osmosis membrane technique stage. The micro-filtration technique stage can pretreat the discharged wastewater of paper making treated by a biochemical system, and remove the impurities of raw water. The ultra-filtration technique stage is used for the treatment of pretreated permeation liquid with ultra-filtration membrane, to further eliminate suspensions and macromolecular particulates. The reserve osmosis membrane technique stage is used for further pressurizing the permeation liquid and desalting through the reserve osmosis membrane and getting rid of COD, thus obtaining ultrapure water for a boiler used in production or permeation liquid used in paper making technique. The invention can thoroughly recycle water resource, and the indexes of the permeation liquid can reach the drinking standard of China, which can absolutely be applied to ultrapure water for the boiler used in production or paper making technique. The invention is applied to advanced recycling of discharged wastewater after wastewater treatment in paper making industry, and is also suitable for advanced recycling of discharged wastewater after wastewater treatment in such industries as printing and dyeing, iron and steel and chemical engineering, etc.

Description

technical field [0001] The invention relates to a method for recycling papermaking industrial wastewater, in particular to a method for advanced treatment of papermaking industrial wastewater by using membrane technology, recycling water resources, and realizing zero discharge. Background technique [0002] Papermaking wastewater has the characteristics of large discharge, complex pollutants, and difficult treatment. Most of them are treated by chemical precipitation, drug flotation, air flotation, and biological oxidation. At present, after being treated by the above-mentioned environmental protection facilities, most of these wastewater are discharged as discharge water. The part that is used for reuse is only treated by traditional three-stage treatment process (ie, dosing, sand filtration, carbon filtration, etc.) and then used as primary reuse water, which is only used for watering flowers, cleaning the ground, etc., and there are problems such as poor water quality, I...

AI Technical Summary

Problems solved by technology

These works are also being carried out in the papermaking industry, but they are limited to the combination of the main process and the supporting process. It is more difficult, and most of them are only in the development and research stage at present.

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