Phenolic resin sewage treatment method

Abstract

The method for treating sewage product from production of phenolic resin includes the procedures of alkaline salt-forming reaction, vacu9um evaporation concentration, decomposition reaction and evaporatino crystallization. In the sewage the alkali is added until the pH value of sewage is 11-12, the they are stirred at normal temp., the sodium phenolate salt aqueous solution can be obtained, underthe conditions of that its vacuum is 0.01-0.015 Mpa, and heated steam pressure is 0.15-0.3 Mpa the above-mentioned solution is concentrated, and its phenol content is 25-30%, then the dilute acid is added in the concentrate until its pH value is 1-3, reacted and stood still, the phenol and residue can be separated and recovered, the residue can be naturally evaporated, and the sodium sulfate can be separated, crystallized and recovered.

Description

technical field [0001] The invention relates to a sewage treatment method, in particular to a treatment method for phenolic resin sewage. Background technique [0002] Phenolic resins are polymerized from phenol and formaldehyde under certain conditions, and are widely used in bakelite composite materials, anti-corrosion materials, binders and paints. The amount of sewage produced by the production of phenolic resin is about 0.4T / T产品 , the phenol content in sewage is 8000~70000mg / L污水 , exceeding the 0.5mg / L污水 Up to tens of thousands of times. There are nearly a thousand manufacturers of phenolic resin in the country, so how to effectively and economically treat phenolic resin sewage is an urgent problem to be solved at present. [0003] For such seriously polluted phenolic resin sewage, the current treatment technologies mainly include the following types: One of the elimination methods is biochemical decomposition method, which must first dilute the sewage hundreds o...

AI Technical Summary

Problems solved by technology

[0003] For such seriously polluted phenolic resin sewage, the current treatment technologies mainly include the following types: One of the elimination methods is biochemical decomposition method, which must first dilute the sewage hundreds of times before performing biochemical treatment, which requires a large investment, and the daily treatment is 3M 3 The calculation of sewage requires an investment of 600,000 yuan, and an average of 300 yuan is required to treat one ton of sewage. The production cost is high, and a large amount of water resources are wasted at the same time, which is not allowed by my country's national conditions.

The second elimination method is chemical oxidation (oxidation with potassium permanganate or ozone), which has high cost and high technical requirements, and is difficult to promote

The recovery and utilization of phenol resources takes organic solvent extraction as an example. Coal tar fraction is used as the extraction agent. The extraction rate is low, the highest is less than 90%, and the phenol content in the treated wastewater still exceeds the standard by thousands of times. Phenol treatment, the process is complicated, the cost is high, and the treatment effect is not ideal

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