Treatment method of cotton pulp wastewater

Abstract

The invention provides a treatment method of cotton pulp wastewater. The treatment method comprises the following steps of: a) providing flocculated cotton pulp; and b) mixing the cotton pulp obtained in step a) with chlorine dioxide for decolorizing treatment. According to the treatment method, a decolorizing agent adopted in the decolorizing treatment is chlorine dioxide which has great discoloring effect on the cotton pulp wastewater, is fast to react, and has relatively high sterilizing effect so that the discharged water which is subjected to discolored by chlorine dioxide has good purification effect on the water quality in the downstream, and has environment-friendly effect; in addition, during discoloring, the chlorine dioxide also can reduce the COD (Chemical Oxygen Demand) of the wastewater, and reduces the comprehensive treatment cost. The chlorine dioxide is fast in discoloring speed and great in discoloring effect, so that a Fenton reactor and a reaction tank are not need to be added in the discoloring process, and as a result, the cost of facility instrument is greatly decreased.

Description

technical field [0001] The invention relates to the technical field of textiles, in particular to a method for treating cotton pulp wastewater. Background technique [0002] Cotton pulp is a kind of paper pulp, which is made by using waste cotton and cotton linters in the textile industry as raw materials and using caustic soda method. Cotton pulp contains relatively pure cellulose, the fibers are slender and elastic, tough and resistant to folding, and have good absorbency. The paper made from is fine and soft, has a high degree of opacity, and can be preserved for a long time. The bleached ones are used to make high-grade printing papers such as filter paper, absorbent base paper, drawing paper, and bond paper. The unbleached one is used to make base paper for steel paper, etc. Sometimes it is also used as a raw material for rayon and cellulose acetate derivatives. [0003] Cotton pulp production is a traditional industry with high energy consumption and high pollution...

AI Technical Summary

Problems solved by technology

[0004] Among the above-mentioned commonly used cotton pulp wastewater treatment methods, the electrolysis method can achieve 60%-72% color removal rate for wastewater, and the color removal effect is remarkable, but the effluent COD Cr The removal rate is only 18.6%, the power consumption per ton of wastewater is about 2.53kW·h, and the cost of decolorization treatment is about 1.85 yuan / t, which is relatively high; Part of the refractory high-molecular organic matter is converted into small-molecular organic matter that is easy to biodegrade, and then through the hydrolysis and acidification process, the C-C bond in the organic molecule is continued to be opened, and the long-chain and cyclic organic matter can be hydrolyzed into short-chain straight chains or bands. Branched organic matter, enhancing the biodegradability of organic matter

The electrolysis plus hydrolysis treatment process has a more obvious effect on removing the chroma of cotton pulp stock solution wastewater, with an average decolorization rate of 86.8%, and an average removal rate of about 41.2% for ammonia nitrogen, but for COD Cr The removal effect is general, the removal rate is only about 28.9%, and the operating cost is relatively high; the removal effect of the hydrolysis plus aerobic process on the chroma is not obvious, only about 20-30% removal rate, but for COD Cr The removal effect is better, up to 60.0% or more

The process of decolorization flocculation, hydrolysis and aerobic process is to add flocculants such as ferrous sulfate and PAM to the cotton pulp raw liquid wastewater, and remove the color of the wastewater through the adsorption of colloidal particles, and the supernatant enters the hydrolysis reactor for hydrolysis and acidification Reaction, continue to improve the biodegradability of wastewater, and finally through aerobic aeration treatment, this process has a good effect on COD Cr The removal effect is better, and the removal rate can reach more than 80%. The removal effect on chroma is more obvious, and the removal rate is about 66%. The final effluent chromaticity of this process still cannot meet the discharge requirements. Even if it can barely meet the requirement, a large amount of flocculation agent will be added, and the cost of the agent will generally exceed 2.5 yuan / ton of water.

[0005] Although these methods disclosed in the prior art can play a certain role in decolorization or COD removal, there are generally some defects, especially the decolorization effect is not good, and the treatment cost is relatively high

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