CN217724613U

CN217724613U - Shift stripping system

Info

Publication number: CN217724613U
Application number: CN202221392333.XU
Authority: CN
Inventors: 罗松
Original assignee: ANHUI QUANSHENG CHEMICAL CO LTD
Current assignee: ANHUI QUANSHENG CHEMICAL CO LTD
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-11-04
Anticipated expiration: 2032-05-31

Abstract

The utility model relates to the technical field of synthetic ammonia, in particular to a conversion stripping system, which comprises an ammonia washing tower, a shell-and-tube preheater, a stripping tower, a stripping liquid booster pump, a low-pressure flash stripping tower of a gasification unit, a stripping water cooler, a stripping water separator and a sulfur recovery unit; the shell-and-tube preheater is provided with a shell-side channel and a tube-side channel for fluid to pass through respectively; wherein the condensate separated from the ammonia washing tower is decompressed, preheated through a tube pass channel of a shell-and-tube preheater and enters a stripping tower for heating and stripping; after the high-temperature condensate of the stripping tower passes through a shell pass channel of the shell-type preheater, the high-temperature condensate is pressurized by a stripping liquid booster pump and is conveyed to the low-pressure flash stripping tower of the gasification unit; the top noncondensable gas of the stripping tower is directly cooled by a stripping water cooler and then enters a stripping water separator to separate out condensed water, and the noncondensable gas is led into a sulfur recovery unit; the utility model discloses effectively avoided the strip liquid booster pump cavitation that the high temperature condensate caused, avoided the frequent damage of strip liquid booster pump.

Description

Shift stripping system

Technical Field

The utility model relates to the technical field of synthetic ammonia, in particular to a conversion stripping system.

Background

In the purification process, the isothermal conversion process matched with the system for synthesizing ammonia by adding pulverized coal into the space furnace mainly plays a role in removing NH in process condensate generated in the conversion process ₃ 、H ₂ S is removed, and then the process condensate is sent back to the gasification device for recycling. If a problem occurs in the shift condensate stripping system, NH ₃ The removal capacity is reduced, which will cause the formation of NH in the process condensate and the process gas of the system ₃ (ii) accumulation of (d); in addition, the shift condensate contains NH ₃ 、CO ₂ And H ₂ S and the like, and equipment corrosion often occurs in a condensate stripping system in production.

Referring to fig. 2, in the conventional stripping process, the condensate separated from the ammonia scrubber 1 is decompressed and enters a shell-and-tube preheater 2 (tube pass) for preheating, and then enters a stripping tower 3 for heating and stripping, the non-condensable gas at the top of the stripping tower 3 enters the shell-and-tube preheater 2 (shell pass) for heat exchange, then enters a stripping water cooler 6 for cooling, and after condensed water is separated by a stripping water separator 7, the non-condensable gas is sent to a sulfur recovery unit 8; the high-temperature condensate of 144 ℃ in the device is pressurized and conveyed to a low-pressure flash evaporation stripping tower 5 of the gasification unit by a stripping liquid booster pump 4. Because the temperature of the condensate is high, the cavitation of the water pump is easy to cause, the water pump is damaged, and the serious threat is brought to the safe production.

SUMMERY OF THE UTILITY MODEL

To solve the problems in the prior art, the present invention aims to provide a shift stripping system.

In order to achieve the above purpose, the utility model adopts the following technical scheme to realize:

a shift stripping system comprises an ammonia washing tower, a shell-and-tube preheater, a stripping tower, a stripping liquid booster pump, a low-pressure flash evaporation stripping tower of a gasification unit, a stripping water cooler, a stripping water separator and a sulfur recovery unit; the shell-and-tube preheater is provided with a shell-side channel and a tube-side channel for fluid to pass through respectively;

after being decompressed, the condensate separated from the ammonia washing tower is preheated through a tube pass channel of the shell-and-tube preheater and then enters the stripping tower for heating and stripping;

after passing through a shell pass channel of the shell-and-tube preheater, the high-temperature condensate of the stripping tower is pressurized and conveyed to the low-pressure flash stripping tower of the gasification unit by the stripping liquid booster pump;

and the non-condensable gas at the top of the stripping tower is directly cooled by the stripping water cooler and then enters the stripping water separator to separate out condensed water, and the non-condensable gas is led into a sulfur recovery unit.

In a further technical scheme, a first valve is arranged on a first pipeline between the ammonia washing tower and the shell-and-tube preheater and used for controlling the flow of low-temperature condensate entering a tube pass channel;

and a second valve is arranged on a second pipeline between the stripping tower and the shell-and-tube preheater and used for controlling the flow of the high-temperature condensate entering the shell-side channel.

Compared with the prior art, the utility model discloses following technological effect has:

the utility model provides a transform steam stripping system, through leading-in the shell side passageway of shell-and-tube type preheater with the high temperature condensate that the stripper was derived, with wash the ammonia tower and separate after getting off decompression treatment and enter the low temperature condensate of the tube side passageway of shell-and-tube type preheater and carry out heat transfer treatment, the temperature of high temperature condensate has effectively been reduced, then the rethread vapor extract booster pump pressurized send to gasification unit low pressure flash distillation stripper; through the utility model provides a transform steam stripping system has effectively avoided the steam stripping liquid booster pump cavitation that the high temperature condensate caused, has avoided the frequent damage of steam stripping liquid booster pump.

Drawings

FIG. 1 shows a schematic block diagram of a shift stripping system provided in accordance with an embodiment of the present invention;

FIG. 2 is a schematic diagram showing the structure of a conventional stripping system;

the reference numbers in the figures illustrate: 1. an ammonia washing tower; 11. a first conduit; 2. a shell-and-tube preheater; 3. a stripping column; 31. a second conduit; 4. a stripping solution booster pump; 5. a gasification unit low pressure flash stripping column; 6. a stripping water cooler; 7. a stripping water separator; 8. a sulfur recovery unit.

Detailed Description

In order to make the technical means, creation characteristics, achievement purpose and efficacy of the utility model easy to understand and understand, the utility model is further clarified by combining the specific drawings.

As described above, with reference to fig. 1, the utility model provides a shift stripping system, which comprises an ammonia washing tower 1, a shell-and-tube preheater 2, a stripping tower 3, a stripping liquid booster pump 4, a gasification unit low-pressure flash stripping tower 5, a stripping water cooler 6, a stripping water separator 7 and a sulfur recovery unit 8; the shell-and-tube preheater 2 is provided with a shell-side channel and a tube-side channel for fluid to pass through respectively;

after the pressure of the condensate separated from the ammonia washing tower 1 is reduced, the condensate is preheated through a tube pass channel of the shell-and-tube preheater 2 and then enters the stripping tower 3 for heating and stripping;

after passing through a shell pass channel of the shell-and-tube preheater 2, the high-temperature condensate of the stripping tower 3 is pressurized and sent to the low-pressure flash evaporation stripping tower 5 of the gasification unit by the vapor extract booster pump 4;

and the non-condensable gas at the top of the stripping tower 3 is directly cooled by the stripping water cooler 6 and then enters the stripping water separator 7 to be separated into condensed water, and the non-condensable gas is led into a sulfur recovery unit 8.

The inventor of the application finds that based on the technical scheme provided by the utility model, condensed fluid separated from the ammonia washing tower 1 is sent into the stripping tower 3 for heating and stripping after being subjected to pressure reduction and preheating treatment through the tube pass channel of the tube shell type preheater 2, non-condensable gas at the top of the stripping tower 3 is directly sent to the stripping water cooler 6 for cooling, and the non-condensable gas is sent into the sulfur recovery unit 8 after condensed water is separated through the stripping water separator 7;

the high-temperature condensate in the stripping tower 3 is fed into a shell-side channel of a shell-and-tube preheater 2 for cooling treatment, and then is fed into a low-pressure flash evaporation stripping tower 5 of the gasification unit through a stripping liquid booster pump 4; therefore, the operation of the steam stripping liquid booster pump 4 is stabilized, the safe and stable production is ensured, the frequent damage of the steam stripping liquid booster pump 4 caused by high-temperature condensate is reduced, and the condensate is forced to be discharged to the sewage treatment environment-friendly risk.

In the existing specific system comparison, the temperature of the condensate separated from the ammonia scrubber 1 after decompression is 40 ℃, according to the traditional stripping system shown in fig. 2, the condensate of 40 ℃ reaches 100 ℃ after being preheated by a tube pass channel of a shell-type preheater 2, is heated by a stripping tower 3, the top noncondensable gas is 144 ℃, is cooled to 134 ℃ through the shell pass channel of the shell-type preheater 2, is cooled to 80 ℃ by a stripping water cooler 6, and is sent to a sulfur recovery unit 8 after being separated from condensed water by a stripping water separator 7; in addition, the high-temperature condensate at 144 ℃ in the stripping tower 3 is pressurized and conveyed to the low-pressure flash stripping tower 5 of the gasification unit by a stripping liquid booster pump 4.

According to the conversion stripping system provided by the utility model, shown by combining with figure 1, the condensate of 40 ℃ reaches 67 ℃ after being preheated through the tube pass channel of the tube shell type preheater 2, is heated by the stripping tower 3, the top noncondensable gas is 144 ℃, is directly sent to the stripping water cooler 6 to be cooled to 80 ℃, and is sent to the sulfur recovery unit 8 after being separated from the condensate water by the stripping water separator 7; and the high-temperature condensate of 144 ℃ in the stripping tower 3 is cooled through a shell passage of the shell-type preheater 2 until the temperature is 120 ℃, and then is pressurized and conveyed to the low-pressure flash stripping tower 5 of the gasification unit through a stripping liquid booster pump 4.

Through the utility model provides an institutional advancement, the working solution temperature of strip liquid booster pump 4 is showing and is reducing, has effectively avoided the strip liquid booster pump cavitation that high temperature caused, has avoided the frequent damage of strip liquid booster pump.

Further, according to the shift stripping system provided by the utility model, in the utility model, a first valve is arranged on a first pipeline 11 between the ammonia washing tower 1 and the shell-and-tube preheater 2 for controlling the flow of the low-temperature condensate entering the tube pass channel;

a second valve is arranged on a second pipeline 31 between the stripping tower 3 and the shell-and-tube preheater 2 and is used for controlling the flow of the high-temperature condensate entering the shell-side channel.

The flow of fluid into the tube-side and shell-side channels of the shell-and-tube preheater 2 is conveniently controlled by the arrangement of the first and second valves, so as to control the degree of heat exchange.

The foregoing shows and describes the general principles, essential features, and features of the invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the description of the above embodiments and the description is only illustrative of the principles of the present invention, and that various changes and modifications may be made without departing from the spirit and scope of the present invention, and these changes and modifications are all within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A shift stripping system comprises an ammonia washing tower (1), a shell-and-tube preheater (2), a stripping tower (3), a stripping liquid booster pump (4), a low-pressure flash stripping tower (5) of a gasification unit, a stripping water cooler (6), a stripping water separator (7) and a sulfur recovery unit (8); the device is characterized in that the shell-and-tube preheater (2) is provided with a shell-side channel and a tube-side channel for fluid to pass through respectively;

wherein the condensate separated from the ammonia washing tower (1) is decompressed, preheated through a tube pass channel of the shell-and-tube preheater (2) and enters the stripping tower (3) for heating and stripping;

after passing through a shell-side channel of the shell-and-tube preheater (2), the high-temperature condensate of the stripping tower (3) is pressurized by the stripping liquid booster pump (4) and then is sent to the gasification unit low-pressure flash stripping tower (5);

and non-condensable gas at the top of the stripping tower (3) is directly cooled by the stripping water cooler (6) and then enters the stripping water separator (7) to be separated into condensed water, and the non-condensable gas is led into a sulfur recovery unit (8).

2. The shift stripping system according to claim 1, characterized in that a first valve is arranged on the first pipe (11) between the ammonia scrubber (1) and the shell-and-tube preheater (2) for controlling the flow of the low-temperature condensate into the tube-side passage;

and a second valve is arranged on a second pipeline (31) between the stripping tower (3) and the shell-and-tube preheater (2) and used for controlling the flow of the high-temperature condensate entering the shell-side channel.