Method and apparatus used for separating and recovering PIA waste residue solvent

Abstract

The invention relates to a method and an apparatus used for separating and recovering a PIA waste residue solvent, the method employs a nitrogen closed circulation system and a micropowder drying technology, PIA is dried by heat nitrogen firstly and acetic acid is volatilized to enter into nitrogen, then a cooling technology is employed to separate acetic acid and nitrogen, and drying of PIA and recovery of acetic acid can be realized finally. According to the invention, drying of PIA and recovery of acetic acid can be realized, and the characteristics of energy saving and consumption reduction, safety and environmental protection can be realized, and the economic benefit and social benefit of the enterprises can be increased.

Description

technical field [0001] The invention provides a method and device for solvent separation and recovery of PIA waste residue, and relates to the technical fields of energy saving, consumption reduction, safety and environmental protection of PIA waste residue. Background technique [0002] Isophthalic acid (1,3-phthalic acid, English abbreviation IPA, high-purity product called PIA) is a white crystalline solid with strong heat resistance, water resistance and chemical resistance, easy to deflagrate, It can be sublimated; its products are important additives in the chemical fiber industry, mainly used in the production of unsaturated polyester resin (UPR), alkyd resin and copolymerized modified polyester. [0003] A large amount of PIA waste residue is produced while producing PIA products. The composition of PIA waste residue is complex, consisting of terephthalic acid, isophthalic acid, benzoic acid, p-toluic acid, p-carboxybenzaldehyde (42CBA), phthalic acid , benzenetrica...

AI Technical Summary

Problems solved by technology

[0004] There are two existing treatment methods for PIA waste residue: direct discharge or landfill in the early stage, direct discharge into the sewer will seriously pollute rivers, direct landfill dumps a large amount of land, and has potential soil pollution and groundwater pollution. The shortcoming is: can not accomplish the reduction, stabilization, harmless treatment of PIA waste residue, lost terephthalic acid, isophthalic acid, benzoic acid, p-toluic acid, p-carboxybenzaldehyde (42CBA ), phthalic acid, benzenetricarboxylic acid and other organic chemical raw materials, so that the organic chemical raw materials have not been comprehensively utilized; in the later stage, a horizontal thin film evaporator is used to conduct thin film evaporation on the PIA waste residue to vaporize the acetic acid and other moisture in the PIA waste residue , and through the acetic acid recovery washing tower in the original PTA device, the acetic acid and other moisture evaporated from the PIA waste residue are cooled and washed to recover acetic acid; Chemical injection into high temperature incinerator for incineration

[0005] ①Thin-film evaporator is used to process PIA waste residue. During the evaporation process of moisture such as acetic acid, due to the backlog effect of the rotors of horizontal thin-film evaporator, PIA waste residue is easy to agglomerate after evaporation of moisture such as acetic acid, and the blocky PIA waste residue is directly incinerated in the incinerator , cannot be fully burned, and the treatment is not complete

[0006] ② Using incineration to treat PIA waste residue can only make terephthalic acid, isophthalic acid, benzoic acid, p-toluic acid, p-carboxybenzaldehyde (42CBA), phthalic acid, benzenetricarboxylic acid, etc. Organic chemical raw materials turn into black ashes after incineration, and organic chemical raw materials are not comprehensively utilized. Dioxin and other pollution sources are likely to be produced in the incineration tail gas.

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