Acid gas water bath cooling device

Abstract

The utility model discloses an acid gas water bath cooling device, which relates to the technical field of coal chemical industry, and comprises a stripping tower, a water bath tank, a stripping tower condenser, a stripping tower separator and a water bath pump, and a gate valve is mounted on the outer surface of the water bath pump input pipeline. The device is small in investment and low in operation cost, condensate (ammonia-containing wastewater) obtained by cooling of the system condenser and separation of the separation tank is circulated in the system, water bath cooling of wet acid gas can be realized, the problems of high ammonia content and corrosion of equipment and pipelines due to ammonia accumulation in the wet acid gas in the prior art are solved, the temperature and pressure of the wet acid gas can be simultaneously reduced, and the production efficiency is improved. Emptying of wet acid gas is reduced, environmental pollution is reduced, the ammonia content in sulfur recovery wet acid gas is reduced, the heat exchange efficiency of the heat exchanger is improved, meanwhile, the scaling rate of the heat exchanger is slowed down, the service life of the heat exchanger is prolonged, and stable operation of the system is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of coal chemical industry, in particular to an acid gas water bath cooling device. Background Art

[0002] At present, the crude process gas of coal-to-methanol projects in the coal chemical industry mostly adopts the sulfur-resistant conversion process. The condensate of this conversion process returns to the gasification device, resulting in the accumulation of ammonia in the process gas and accelerated corrosion of equipment pipelines. To this end, a stripping unit is set up to treat part of the process condensate to reduce the ammonia content in the process gas. The stripping tower uses 0.5MPa low-pressure steam and gasification high flash steam as the stripping medium to strip the ammonia in the process condensate, and then cools and separates the condensate through a water cooler to obtain ammonia-containing gas; the ammonia-containing gas is sent to sulfur recovery to recover sulfur; the separated liquid is called ammonia-containing wastewater, which is sent to the power unit as an absorbent for the ammonia desulfurization system.

[0003] During operation, the two flash evaporation systems of gasification have a large amount of high flash gas, which enters the conversion stripping system at the same time, causing the pressure of the conversion stripping system to increase. The wet acid gas pressure is too high and will be vented, causing environmental pollution. At the same time, the condenser on the top of the stripping tower has serious corrosion and scaling problems, which brings great safety hazards to production, resulting in high saturated water vapor in the wet acid gas sent to sulfur recovery, affecting the sulfur yield and the normal operation of the sulfur recovery section.

[0004] In view of the above problems, the inventors proposed an acid gas water bath cooling device to solve the above problems. Utility Model Content

[0005] In order to solve the problems of large flash gas volume in two flash evaporation systems of gasification and corrosion and scaling of the condenser at the top of the stripping tower; the purpose of the utility model is to provide an acid gas water bath cooling device.

[0006] In order to solve the above technical problems, the utility model adopts the following technical scheme: an acid gas water bath cooling device, comprising a stripping tower, a water bath tank, a stripping tower condenser, a stripping tower separator and a water bath pump, one end of the stripping tower is provided with a wet acid gas pipeline, the wet acid gas pipeline is connected to the water bath tank, a water bath tank outlet pipeline is connected between the water bath tank and the stripping tower condenser, an inner plug-in water bath pipeline is inserted inside the water bath tank, a stripping tower condenser outlet pipeline is connected between the stripping tower condenser and the stripping tower separator, the stripping tower separator and the water bath pump are connected through a water bath pump input pipeline, a gate valve is installed on the outer surface of the water bath pump input pipeline, a water bath pump outlet valve is provided on the water bath pump, a water bath pump outlet pipeline is provided at one end of the water bath pump, and the water bath pump outlet pipeline is connected to the wet acid gas pipeline.

[0007] Preferably, a check valve and an outlet gate valve are installed on the outer surface of the water bath pump outlet pipeline. During normal operation, the internal pressure of the stripping system is changed to 0.25-0.3 MPa. The temperature range of the wet acid gas pipeline (2) is 127°C-133°C. Preferably, at 130°C, the liquid level of the stripping tower separator is established normally. The plug-in water bath pipeline uses a DN400 304 stainless steel pipe. The inlet and outlet temperatures of the stripping tower condenser are adjusted by the outlet valve on the water bath pump. The outlet of the plug-in water bath pipeline of the water bath tank is made into a serrated shape with a sawtooth length of 150 mm and a sawtooth angle of 30°. The wet acid gas pipeline serves as the water bath tank inlet pipeline, and the centerline heights of the wet acid gas pipeline and the water bath tank outlet pipeline are both 200 mm. The materials of the outlet pipelines are the same. The outer cylinder wall of the water bath tank is made of a DN600 duplex stainless steel pipe.

[0008] Compared with the prior art, the beneficial effects of the utility model are:

[0009] 1. This device requires small investment and low operating costs. The condensate (containing ammonia wastewater) obtained by condensation in the system condenser and separation in the separation tank is circulated in the system to achieve water bath cooling of the wet acidic gas. The technology is simple and easy to operate.

[0010] 2. The wet acid gas is cooled by water bath, which reduces the temperature and pressure of the wet acid gas, reduces the venting of the wet acid gas due to high pressure, and reduces environmental pollution.

[0011] 3. This device improves the heat exchange efficiency of the heat exchanger, while slowing down the scaling rate of the heat exchanger, extending the service life of the heat exchanger and ensuring the stable operation of the system.

[0012] 4. Cooling the wet acid gas in a water bath can increase the solubility of ammonia in the condensate. The ammonia-containing wastewater condensed by the stripping tower condenser is recycled and sent to the power desulfurization system to remove sulfur dioxide from the tail gas, saving energy and reducing consumption, and saving the amount of ammonia water. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is the process flow chart of the utility model.

[0015] Figure 2 This is a schematic diagram of the structure of a water bath tank of the utility model.

[0016] Figure 3It is a schematic diagram of the cross-sectional structure of the water bath tank of the utility model.

[0017] In the figure: 1. Stripping tower; 2. Wet acid gas pipeline; 3. Water bath tank; 4. Insert water bath pipeline; 5. Water bath tank outlet pipeline; 6. Stripping tower condenser; 7. Stripping tower condenser outlet pipeline; 8. Stripping tower separator; 9. Water bath pump input pipeline; 10. Gate valve; 11. Water bath pump; 12. Water bath pump outlet pipeline; 13. Check valve; 14. Outlet gate valve. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] Embodiment 1:

[0020] like Figure 1-3 As shown, the utility model provides an acid gas water bath cooling device, comprising a stripping tower 1, a water bath tank 3, a stripping tower condenser 6, a stripping tower separator 8 and a water bath pump 11, one end of the stripping tower 1 is provided with a wet acid gas pipeline 2, the wet acid gas pipeline 2 is connected to the water bath tank 3, a water bath tank outlet pipeline 5 is connected between the water bath tank 3 and the stripping tower condenser 6, an inner plug-in water bath pipeline 4 is inserted inside the water bath tank 3, a stripping tower condenser outlet pipeline 7 is connected between the stripping tower condenser 6 and the stripping tower separator 8, the stripping tower separator 8 and the water bath pump 11 are connected through a water bath pump input pipeline 9, a gate valve 10 is installed on the outer surface of the water bath pump input pipeline 9, one end of the water bath pump 11 is provided with a water bath pump outlet pipeline 12, and the water bath pump outlet pipeline 12 is connected to the wet acid gas pipeline 2. The premise for the normal operation of the water bath cooling device is that the water bath pump 11 operates normally; the premise for the normal operation of the water bath pump 11 is that the liquid level of the stripping tower separator 8 is stable; therefore, the premise for the normal operation of the water bath cooling device is that the liquid level of the stripping tower separator 8 is stable.

[0021] A check valve 13 and an outlet gate valve 14 are installed on the outer surface of the water bath pump outlet pipeline 12 .

[0022] By adopting the above technical solution, it is convenient to control the water bath pump outlet pipeline 12.

[0023] During normal operation, the internal pressure of the stripping system is changed to 0.25-0.3 MPa, the temperature range of the wet acid gas pipeline 2 is 127°C-133°C, and preferably when the temperature of the wet acid gas pipeline 2 is about 130°C, the liquid level of the stripping tower separator 8 is established normally.

[0024] By adopting the above technical solutions, an ideal environment for normal operation is created.

[0025] The internal water bath pipeline 4 is made of DN400 304 stainless steel pipe.

[0026] By adopting the above technical solution, the structural strength is high and the use effect is good.

[0027] The inlet and outlet temperatures of the stripping tower condenser 6 are adjusted by the outlet valve on the water bath pump 11.

[0028] By adopting the above technical solution, the adjustment is convenient and the operation is simple.

[0029] The outlet 4 of the water bath tank internal plug-in water bath pipeline is made into a sawtooth shape, the sawtooth length is 150mm, and the sawtooth angle is 30°.

[0030] By adopting the above technical solution, the flow state of the fluid is changed and the flow rate of the fluid is slowed down, so as to improve the water-gas contact efficiency and reduce the loss to the equipment.

[0031] The wet acid gas pipeline 2 serves as the water bath tank inlet pipeline, and the centerline heights of the wet acid gas pipeline 2 and the water bath tank outlet pipeline 5 are both 200 mm.

[0032] By adopting the above technical solution, it is ensured that after the water bath tank reaches a normal liquid level, part of the liquid overflows at the bottom of the water bath tank outlet pipe 5, so that the water bath cooling is continuously performed.

[0033] The outer wall of the water bath tank 3 is made of DN600 duplex stainless steel pipe.

[0034] By adopting the above technical solution, the structural strength is high and the service life is long.

[0035] Working principle: open the water bath pump inlet gate valve 10, start the water bath pump 11 to run normally, open the outlet gate valve 14, and transport part of the ammonia-containing wastewater to the wet acid gas pipeline 2. The wet acid gas is mixed with the ammonia-containing wastewater and enters the water bath tank 3. The ammonia-containing wastewater gradually fills the plug-in water bath pipeline 4 by its own gravity, causing the water bath tank 3 to gradually establish a liquid level. The liquid level of the water bath tank 3 reaches the pipe mouth of the water bath tank outlet pipeline 5, and part of the liquid overflows into the stripping tower condenser 6; the high-temperature wet acid gas continuously enters the plug-in water bath pipeline 4 and comes out from the bottom serrated mouth in the water bath tank 3. The water vapor is fully contacted and finally enters the stripping tower condenser 6 and the stripping tower separator 8 from the water bath tank outlet pipeline 5 for further condensation and separation. The water bath cooling process is continuously circulated in the system, thereby achieving the effect of water bath cooling.

[0036] The inlet and outlet temperatures of the stripping tower condenser 6 are adjusted through the water bath pump outlet valve to avoid fluctuations in the stripping system, requiring multiple small adjustments.

[0037] The advantages of this embodiment are:

[0038] The device overcomes the difficulties of the prior art and has the characteristics of reducing the temperature and pressure of the wet acid gas in the stripping system, preventing the wet acid gas from being vented at high pressure and polluting the environment. At the same time, it can slow down the scaling rate of the stripping tower condenser 6, reduce the frequency of chemical washing of the heat exchanger, and extend the service life of the heat exchanger, thereby improving the use efficiency and service life of the heat exchanger.

[0039] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An acid gas water bath cooling device, comprising a stripping tower (1), a water bath tank (3), a stripping tower condenser (6), a stripping tower separator (8) and a water bath pump (11), characterized in that: A wet acid gas pipeline (2) is provided at one end of the stripping tower (1), and the wet acid gas pipeline (2) is connected to a water bath tank (3). A water bath tank outlet pipeline (5) is connected between the water bath tank (3) and the stripping tower condenser (6). An internal plug-in water bath pipeline (4) is inserted into the water bath tank (3). A stripping tower condenser outlet pipeline (7) is connected between the stripping tower condenser (6) and the stripping tower separator (8). The stripping tower separator (8) and the water bath pump (11) are connected via a water bath pump input pipeline (9). A gate valve (10) is installed on the outer surface of the water bath pump input pipeline (9). A water bath pump outlet pipeline (12) is provided at one end of the water bath pump (11), and the water bath pump outlet pipeline (12) is connected to the wet acid gas pipeline (2).

2. The acid gas water bath cooling device according to claim 1, characterized in that: A check valve (13) and an outlet gate valve (14) are installed on the outer surface of the water bath pump outlet pipeline (12).

3. The acidic gas water bath cooling device according to claim 1, characterized in that: The temperature range of the wet acid gas pipeline (2) is 127°C-133°C.

4. The acidic gas water bath cooling device according to claim 1, characterized in that: The internal water bath pipeline (4) is made of DN400 304 stainless steel pipe.

5. The acidic gas water bath cooling device according to claim 1, characterized in that: The inlet and outlet temperatures of the stripping tower condenser (6) are adjusted by the outlet valve on the water bath pump (11).

6. The acidic gas water bath cooling device according to claim 1, characterized in that: The inner plug-in water bath pipeline (4) is made into a sawtooth shape, the sawtooth length is 150 mm, and the sawtooth angle is 30°.

7. The acidic gas water bath cooling device according to claim 1, characterized in that: The wet acid gas pipeline (2) serves as the water bath tank inlet pipeline, and the centerline heights of the wet acid gas pipeline (2) and the water bath tank outlet pipeline (5) are both 200 mm.

8. The acid gas water bath cooling device according to claim 1, characterized in that: The outer cylinder wall of the water bath tank (3) is made of a DN600 duplex stainless steel pipe.

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