Butadiene tail gas hydrogenation unit and method

Abstract

The invention discloses a butadiene tail gas hydrogenation unit and method. The unit comprises a hydrogenation reactor and a gas-liquid separating tank, wherein an absorption tower and a compressor are arranged in front of the hydrogenation reactor; the top of the absorption tower is sequentially connected with the compressor, a condenser and a compressor drain tank, merged with a pipeline on the bottom of the absorption tower, and connected with the inlet of the hydrogenation reactor; the outlet of the hydrogenation reactor is connected with the gas-liquid separating tank; the bottom of the gas-liquid separating tank is provided with two pipelines; and one pipeline is connected with the inlet of the hydrogenation reactor, and the other pipeline is communicated with the outside. The method comprises steps as follows: (1) butadiene tail gas is absorbed by a liquid-phase C4 absorbent in the absorption tower; and (2) the gas phase on the top of the absorption tower is compressed and condensed, then mixed with the liquid phase on the tower bottom, and mixed with hydrogenated products and hydrogen, and the mixture enters the hydrogenation reactor to perform hydrogenation reaction. By combining the absorption tower with the compressor, the unit and method disclosed by the invention solve the problems of gas-phase material pressure increase, condensation, unit operation safety and the like.

Description

technical field [0001] The invention relates to the field of petrochemical industry, in particular to a butadiene tail gas hydrogenation device and method. Background technique [0002] The 1,3-butadiene in cracking C4 hydrocarbons is usually refined by two-stage solvent extraction rectification and then direct rectification. The residual waste gas produced by this refining device is commonly known as butadiene tail gas. Extractive distillation is also called extraction, and the recovery device of butadiene is generally called butadiene extraction device. The alkyne concentration in the butadiene tail gas is relatively high, generally greater than 20% by weight, and the highest can exceed 40% by weight. These alkyne-rich waste gases have no industrial value at present and can only be sent to torch for combustion. Because high-concentration alkynes are easy to polymerize and explode, they must be diluted with raffinate containing butane and butene before being sent to the t...

AI Technical Summary

Problems solved by technology

[0008] In order to solve the operational safety problems caused by the difficult liquefaction of butadiene tail gas raw materials and the high content of alkynes in the prior art, the present invention provides a butadiene tail gas hydrogenation device and method

Through the combination of absorption tower and compressor, the problems of gas phase material boosting, condensation and device operation safety are solved.

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