Treatment system for removing cellulose from papermaking wastewater

Abstract

The invention discloses a treatment system for removing cellulose from papermaking wastewater. The treatment system comprises a water collection well, a coarse screen, a primary sedimentation tank, a pH value regulation tank, an ultrasonic catalytic crosslinking and cellulose filter-pressing separation system, an aeration tank, a biological oxidation filter tank, a secondary sedimentation tank and a water purification tank. By innovatively taking the advantage that cellulose has a characteristic of crosslinking reaction in existence of certain weak acid substances, citric acid is selected as a crosslinking agent, and trisodium citrate is selected as a catalyst; the citric acid and the trisodium citrate are added into papermaking wastewater containing a great quantity of natural celluloses to realize well mixing, and then the citric acid and the natural celluloses are in cyclic anhydride-esterification reaction under catalytic activation action of ultrasonic to generate a cellulose gel substance with a space chemical cross-linked structure. The cellulose gel substance is insoluble in water and has a flocculation characteristic, and accordingly flocculent settling and purification of high-concentration COD in the papermaking wastewater can be realized, and simultaneous removal of COD and celluloses in the papermaking wastewater is realized.

Description

technical field [0001] The invention relates to a treatment system for removing cellulose in papermaking wastewater, which belongs to the field of wastewater treatment in environmental protection. Background technique [0002] The paper industry is a traditional large water user in my country, and it is also one of the important sources of water pollution. At present, my country's paper industry wastewater discharge and COD discharge rank first among all types of industrial emissions, and the paper industry is the most serious pollution to the water environment. the primary issue to be addressed. According to statistics, the discharge of papermaking and paper products industrial wastewater at or above the county level in my country accounts for 18.6% of the total industrial discharge in the country, of which the amount of treated discharge reaching the standard accounts for 49.3% of the total discharge of papermaking industrial wastewater. Papermaking wastewater is produced...

AI Technical Summary

Problems solved by technology

However, this method requires a relatively complicated process flow, and at the same time requires a large equipment investment and floor area, and is not suitable for large-scale promotion and use.

[0010] At present, the existing methods for treating cellulose in papermaking wastewater have problems such as single technical route, unsatisfactory treatment effect, complicated process and equipment, high cost, and easy to cause secondary pollution.

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