A Benzene Washing Process for Cooling and Washing Oil Inside the Tower

Abstract

The invention discloses a benzene washing process of cooling washing oil inside a tower. The process comprises the following steps: introducing coke oven gas into the lower end of a benzene washing tower, and spraying the washing oil from the top of the benzene washing tower; mixing washing oil with coke oven gas in a tube pass of a heat exchanger, and controlling the temperature of the heat exchanger in the tube pass in a range of 22 to 26 DEG C; filling heat-adsorption solutions with a shell pass of the heat exchanger; carrying out heat exchange of the heat-adsorption solutions as well as the washing oil and the coke oven gas to control the temperature of the washing oil caused by the heat energy released by adsorbing benzoic hydrocarbon in the coked oven gas to rise, wherein a pressure sensor, a vacuum pump and a liquid level meter are arranged on the pipe pass of the heat exchanger shell, and the pressure sensor is used for controlling starting / stopping of the vacuum pump to maintain the inner pressure of the shell pass to be micro-vacuumized in the range of 2000 to 3000 Pa; heating rich oil and feeding the rich oil into a benzole scrubber for treatment to obtain poor oil; and adding the poor oil into the washing oil and recycling together back to a benzene washing tower. Compared with an existing process of enlarging the washing circulation amount to improve the recycling rate of benzole, under the same using consumption of the washing oil, the recycling rate of benzole is at least increased by 20%, and the increment of integral energy consumption is few.

Description

technical field [0001] The invention relates to the field of coal coking benzene washing, in particular to a benzene washing process for cooling and washing oil inside a tower. Background technique [0002] In the chemical industry, it is often necessary to separate the components in the gas mixture to recover useful substances in the gas mixture to increase economic benefits; or to remove harmful substances in it to prevent environmental pollution. [0003] In the existing coke oven gas purification equipment and process, the washing oil is usually used as the absorbent to recycle the benzene group hydrocarbons. The washing oil will release heat of dissolution during the process of absorbing the benzene group hydrocarbons, and the washing oil absorption temperature and The recovery rate of benzene group hydrocarbons has a very large correlation, and the washing oil temperature is around 25°C, the temperature is the most suitable at this time, and the recovery rate of crude ...

AI Technical Summary

Problems solved by technology

However, due to the release of the heat of solution, the temperature of the washing oil will be continuously increased, so that the temperature of the washing oil inside the benzene washing tower is much higher than the appropriate absorption temperature, resulting in a low absorption efficiency of crude benzene

In order to control the benzene content after the tower, the existing benzene washing process adopts the method of increasing the washing oil circulation volume, and the increase of the washing oil supply is used to overcome the influence of the reduction of the crude benzene absorption rate, so not only the washing oil consumption is increased, but the corresponding follow-up The processing capacity of rich oil also increases, which increases the operating cost and power consumption, which is not conducive to the improvement of the overall performance of the process