Cleaning process for outer cooling shift gas alkali preparation

Abstract

The invention discloses a cleaning process in external cooling gas-transforming alkali preparation. At least two external cooling type carbonizing towers are paralleled into a set; each carbonizing tower is connected with a set of external coolers; after working for days, each carbonizing tower is cleaned alternately, and the connected external coolers are also cleaned at the same time. In the cleaning period, other carbonating towers but the one being cleaned continue the alkali preparing work; in cleaning, ammonia mother liquid 2 is introduced into the cleaned tower, and at the same time, one part of carbonized exhaust coming out from the alkali preparing towers is also introduced into the cleaned tower after being pressurized to accelerate dissolution of scars in the cleaned tower; the exhaust coming out from the cleaned tower is combined into the other part of the carbonized exhaust coming out from the alkali preparing towers and, used as raw material decarburizing gas for synthetic ammonia production, is sent with the ammonia mother liquid 2 discharged out of the cleaned tower into the alkali preparing towers for the alkali preparation. The cleaning process of the invention has no sewage discharge and does not pollute the environment; in addition, two to six or even more towers can be paralleled into a set for the alkali preparation, thereby significantly improving the working efficiency of the towers and reducing the adverse effect caused to the production by cleaning operation.

Description

technical field [0001] The invention relates to a cleaning process of an external cooling type carbonization tower, which is equipment in an external cooling shift gas alkali production process, and belongs to the technical field of chemical industry. Background technique [0002] Changed gas soda production is a new soda production process created by our country. It directly passes the shifted gas in the production of ammonia into the carbonization tower of soda ash production. On the one hand, it produces heavy alkali (NaHCO 3 ), on the other hand, the CO in the shift gas is removed 2 , Combining the decarburization process in the production of synthetic ammonia with the compression process and carbonization process in the production of combined alkali, which has a significant effect on energy saving and investment saving. In 1998, China Chengda Engineering Co., Ltd. cooperated with Shijiazhuang United Soda Plant to develop an externally cooled carbonization tower (referr...

AI Technical Summary

Problems solved by technology

After adopting the operation of series towers, the tail gas of the soda making tower is further absorbed by the cleaning tower, and the CO in the tail gas of the cleaning tower is discharged. 2 The concentration can meet the requirements of synthetic ammonia production, and at the same time solve the problem of cleaning the gas source; however, the string tower process has two major disadvantages: one is that the converted gas needs to pass through two towers, the pressure drop of the system increases, and the energy consumption is large; the other is the carbonization tower There can only be a group of three towers at most, otherwise the gas velocity of the cleaning tower is too high, and the gas discharge is serious, which actually reduces the operation rate of the tower

In addition, the angle valve rubber pad between the carbonization tower and the external cooler also has a certain service life and needs to be replaced regularly. The normal production will also be affected when the rubber pad is replaced.

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