Comprehensive treatment and resource utilization technology of 2-naphthol production wastewater

Abstract

The invention discloses a comprehensive treatment and resource utilization technology of 2-naphthol production wastewater. In the technology, the 2-naphthol production wastewater is directly acidified, and the discharged SO2 gas is absorbed and recycled by alkaline liquid; after the desulfurization wastewater is filtered to remove insoluble substance, two-level extraction is performed by use of acomplexing extracting agent; the extract phase is subjected to stripping by alkaline liquid, and the regenerated extracting agent is circularly utilized; the first-level strip liquor is cooled and filtered to obtain naphthalene sulfonate solid which is reused in a 2-naphthol hydrolysis naphthalene blowing process; the filtrate and the strip liquor of the second-level extraction are transferred toan evaporation system for evaporation concentration and then fed to a water reducing agent synthesis process; and the evaporation condensate water and the raffinate phase of the second-level extraction are subjected to oxidation flocculation treatment to reach the standard. The technology disclosed by the invention has reasonable design and treats the 2-naphthol production wastewater while realizing resource utilization of the wastewater.

Description

technical field [0001] The invention relates to a process for treating waste water from the production of naphthalene chemical products, specifically a process for resource utilization of useful substances such as sodium naphthalenesulfonate and sodium sulfite in the waste water produced by 2-naphthol and comprehensive treatment of the waste water. Background technique [0002] 2-Naphthol is a fine chemical intermediate. The traditional production method is to use refined naphthalene as raw material through sulfonation, hydrolysis, neutralization, alkali fusion, acidification, refining and other processes. The production of 2-naphthol per ton is about Produce 10 tons of waste water. The wastewater has high salt content, high toxicity, and deep color. It mainly contains sodium naphthalenesulfonate, sodium methylnaphthalenesulfonate, sodium sulfonate, sodium sulfite, and sodium sulfate of heteroindenes, among which sodium naphthalenesulfonate is 16000~ 25000mg / L, sodium sulf...

AI Technical Summary

Problems solved by technology

The "resin adsorption method" process has high operating conditions and requirements, short resin saturation time, frequent backwashing, high resin price, and large equipment investment; the main disadvantage of the membrane separation method is that the performance of various membranes is unstable, and the membrane pores are easy to block; direct The chemical oxidation method is costly; the biochemical method is difficult to treat wastewater with high COD, and the wastewater of naphthalene dye intermediates is extremely difficult to degrade, and the required microorganisms must be specially domesticated and cultivated

Extraction method, resin adsorption method or evaporation concentration can concentrate the chemical substances in 2-naphthol wastewater. These substances are mainly sodium 2-naphthalenesulfonate, sodium 1-naphthalenesulfonate, sodium methylnaphthalenesulfonate, Sodium oxarunaphthalene sulfonate, sodium azaindene naphthalene sulfonate, sodium thiaindene sulfonate, sodium naphthalene disulfonate, etc. have complex components and cannot be directly used simply. They are treated by centralized incineration. The disadvantage is that High investment and energy consumption costs, no recycling of resources

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