Sulfonated tail gas recycling method and sulfonated tail gas recycling system

Abstract

The present invention relates to a sulfonated tail gas recycling method and a sulfonated tail gas recycling system. The purpose of the present invention is to provide the method and the system, wherein the method and the system have characteristics of less waste gas discharge and less wastewater discharge, and the system has characteristics of reasonable structure, easy manufacture, and low cost. The technical scheme is that: the sulfonated tail gas recycling method comprises the following steps that: dry air enters the lower part of a sulfur trioxide evaporator, and is subjected to counter current contact with liquid sulfur trioxide entering the upper part of an vaporizing mixer so as to evaporate into the sulfur trioxide gas; the sulfur trioxide gas is cooled, enters a sulfonator, is subjected to a contact reaction with an organic material in the sulfonator, and then is output; the sulfonated tail gas is separated from the liquid, wherein the separated liquid material is output and enters a neutralization system, the separated sulfonation tail gas enters an electrostatic demister to carry out a demisting treatment, the partial discharged sulfonated tail gas enters an alkali washing processing system, and the remaining sulfonated tail gas is conveyed to the lower part of the sulfur trioxide mixing evaporator to recycle. The pipeline system of the sulfonated tail gas recycling system is arranged according to the method.

Description

technical field [0001] The invention relates to the field of fine chemical production and aims to provide a method for recycling sulfonated tail gas and a system for recycling sulfonated tail gas. Background technique [0002] Among the surfactant products, the output of anionic surfactants occupies a considerable proportion, and the sulfur trioxide sulfonation method is one of the most important means of producing anionic surfactants. According to statistics, there are more than 100 sets of sulfonation devices in operation in my country, with an annual output of more than 1 million tons. At the same time, a large amount of sulfonation tail gas is produced. The tail gas still contains unconverted sulfur dioxide, unreacted sulfur trioxide gas, Sulfuric acid mist and organic acid mist will seriously pollute the environment if they are discharged directly. In order to meet the environmental protection emission requirements, they must be treated before they can be discharged. Su...

AI Technical Summary

Problems solved by technology

According to statistics, there are more than 100 sets of sulfonation devices in operation in my country, with an annual output of more than 1 million tons. At the same time, a large amount of sulfonation tail gas is produced. The tail gas still contains unconverted sulfur dioxide, unreacted sulfur trioxide gas, Sulfuric acid mist and organic acid mist will seriously pollute the environment if they are discharged directly. In order to meet the environmental protection emission requirements, they must be treated before they can be discharged.

Sulfur dioxide and sulfur trioxide can be removed by alkali washing, but the organic acid mist entrained in the tail gas will produce a large amount of foam during the alkali washing process, which will affect the normal operation of alkali washing

The particle size of these organic acid mist is very small, about 0.1-1.0 μm, it is difficult to effectively separate through the gas-liquid separator

At present, most domestic manufacturers use electrostatic precipitators (ESP) to capture and remove them, and the tail gas is further treated by alkali washing to meet the standard before being discharged into the atmosphere; the wastewater generated by alkali washing (containing a large amount of inorganic salts), Generally, it is discharged directly after dilution treatment. Using this treatment method will not only still affect the environment, but also the cost of treatment will become higher and higher.

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