Method and device for recovering gas containing water-soluble organic compounds

Abstract

The invention relates to a method and a device for recovering gas containing water-soluble organic compounds. The method includes steps of using saturated water vapor to carry out desorption for waste gas adsorbed by a absorber, conveying desorbed gas containing mixture of air and liquid from the third minute to the fifth minute after the desorption begins to a desorption gas condenser to condense under 40 DEG C, conveying the condensed gas into a gas-liquid phase-splitter to carry out gas liquid separation, pumping water solution containing the solvent into a reboiler to vaporize by heating, conveying the gas into a distillation tower for rectifying after vaporizing; directly conveying desorbed gas not containing the mixture of air and liquid 5 minutes after the desorption begins into the distillation tower for rectifying, controlling tower top temperature of the distillation tower in a range of + / - 1 DEG C of boiling point of the water-soluble organic compounds, and obtaining the water-soluble organic compounds capable of being circularly used after conveying tower top fraction into a fraction condenser to condense to temperature lower than 40 DEG C. The invention not only can excellently recovers waste gas, but also reduces heat energy consumption by more than 40% in device operation process.

Description

technical field [0001] The invention relates to a method and a device for recovering waste gas containing water-soluble organic compounds. Background technique [0002] Water-soluble organic compound waste gas mainly refers to waste gas containing volatile organic compounds such as alcohols, ketones, esters, ethers, etc. This kind of waste gas is often mixed with air. It is used in printing (coating) industry, organic chemical industry, petroleum In the production process of chemical, pharmaceutical and other industries, a large amount of waste gas of such industrial organic compounds will be discharged, such as industrial waste gas containing ethanol, methanol, acetone, butanone, ethyl acetate, butyl acetate, ethylene glycol ether, etc. For the recovery technology of this type of organic compound waste gas, Chinese patent ZL200610161012.8 discloses a representative method, that is, using activated carbon fiber adsorber to absorb and recover, and then desorb the activated ca...

AI Technical Summary

Problems solved by technology

The above-mentioned process has the following defects through practice: 1. The analytical steam that has already belonged to the vaporization state must first be condensed into a liquid state, and then heated by a heat source into a vaporization state. This process of first condensing and then heating has caused a large amount of thermal energy loss. Waste; 2. It needs to invest in a heat exchanger with a large heat exchange area

The above defects make the waste gas recovery and refining process of water-soluble organic compounds consume a lot of heat energy, and the recovery cost is high, which seriously affects the economic benefits of the enterprise

[0003] If the desorption steam directly enters the rectification tower without condensation, naturally there is no waste of heat energy, which is of course ideal, but from a technical point of view, the following two aspects must be overcome: 1. Due to the early stage of desorption, the remaining in the adsorber Air, resulting in a large amount of non-condensable air in the desorbed steam, which affects the separation of vapor and liquid, resulting in continuous rectification; 2. In a set of equipment, because the analysis is not continuous, it directly causes the desorbed steam to enter the rectification The tower is intermittent and discontinuous. Such desorption steam entering the rectification tower will cause the temperature at the top of the tower to fluctuate, making rectification impossible.

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