Production process for reducing liquid carried by alkylation tail gas of ethylbenzene device

Abstract

The invention discloses a production process for reducing liquid carried by alkylation tail gas of an ethylbenzene device, which comprises the following steps of: ethane separation, alkylation reaction and ethylbenzene separation: adding the alkylation tail gas into a compressor, conducting pressurizing, introducing the pressurized gas into the bottom of an absorption tower, sucking the alkylation tail gas into the top of the absorption tower by using an absorbent, after the alkylation tail gas is in contact with the absorbent in the absorption tower, discharging the tail gas from the top of the tower, enabling the crude separation tower bottom liquid to enter a benzene tower, removing non-aromatic hydrocarbons, extracting benzene, and obtaining the benzene tower bottom liquid, namely, crude ethylbenzene. According to the production process for reducing the liquid carried by the alkylation tail gas of the ethylbenzene device, the operation parameters of the crude separation tower and the absorption tower are optimized to reduce the temperature of the alkylation tail gas entering the absorption tower, so that the tower top temperature of the absorption tower is reduced, the purpose of reducing the liquid carried by the alkylation tail gas is achieved, the water quality of the wet air cooler is analyzed regularly every week, and timely adjustment is performed according to the analysis result; and the water quality requirement is met, stable operation of the device can be ensured, meanwhile, part of energy consumption and material consumption of the device are reduced, and economic benefits of companies are improved.

Description

technical field [0001] The invention relates to the technical field of ethylbenzene, in particular to a production process for reducing liquid carryover in the alkylation tail gas of an ethylbenzene unit. Background technique [0002] Ethylbenzene is an aromatic hydrocarbon that exists in coal tar and certain diesel oils. It is flammable. Its vapor and air can form explosive mixtures. When exposed to open flames, high heat or contact with oxidants, there is a danger of combustion and explosion. Although it exists in crude oil A small amount of ethylbenzene, but large-scale production still relies on the reaction of benzene and ethylene under acid catalysis. Ethylbenzene undergoes catalytic dehydrogenation to generate hydrogen and styrene. Ethylbenzene also exists in some pigments, mainly used to produce styrene , and then produce styrene homopolymers and copolymers with styrene as the main component. The styrene produced is generally used to prepare commonly used plastic pro...

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to provide a kind of production technology that reduces the ethylbenzene plant alkylation tail gas carrying liquid, to solve the above-mentioned background technology, propose that the current domestic dry gas system ethylbenzene device is gradually replaced by the liquid phase process ethylbenzene device, but For the combined unit, it is necessary to have a device for producing ethylbenzene by the dry gas method. The dry gas produced by the catalytic cracking of the combined unit contains a certain amount of olefins. In order to maximize the utilization of ethylene in the dry gas, Only the olefins in the dry gas can be consumed by the gas-phase ethylbenzene plant to produce ethylbenzene. In this process, when the dry gas volume of the upstream device is too large, since the cooling at the top of the crude fractionation tower is cooled by the fan, especially During production in summer, the cooling effect of the fan is not good. In order to further improve the absorption effect, the amount of absorbent has to be increased, which finally makes the tail gas of hydrocarbonation carry more liquid, which not only affects the operation of the raw gas compressor of the aromatics unit, but also The furnace temperature of the heating furnace in the device is affected, causing the problem of fluctuations in the device