Gas treatment device

Abstract

The invention provides a gas treatment device, comprising: an absorption tower having a liquid inlet and a liquid outlet; the desorption tower is communicated with the liquid inlet through a barren liquor pipeline, and the desorption tower is communicated with the liquid outlet through a rich liquor pipeline; the air separation device is provided with a discharge port; wherein the barren liquor pipeline is provided with a first heat exchanger, the discharge port is communicated with the first heat exchanger through a first communicating pipeline, and the first heat exchanger can conduct heat exchange treatment on fluid in the barren liquor pipeline and fluid in the first communicating pipeline. According to the technical scheme, the problem that the cooling capacity of waste nitrogen is wasted due to the fact that the cooling capacity of the waste nitrogen discharged by the air separation process is not recycled in the related technology is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas processing devices, and in particular to a gas processing device. Background Art

[0002] The air separation unit is used to separate rare gases such as oxygen and argon from the air. The dirty nitrogen gas discharged from the air separation unit is the largest tail gas discharged by the air separation unit in the coal gasification system. The dirty nitrogen gas discharged from the air separation unit contains a certain amount of cold energy.

[0003] In the related art, the contaminated nitrogen gas discharged from the air separation device is directly discharged into the atmosphere, and the cooling capacity of the contaminated nitrogen gas discharged from the air separation device is not recovered and utilized, resulting in a waste of cooling capacity of the contaminated nitrogen gas. Summary of the invention

[0004] The main purpose of the present invention is to provide a gas processing device to solve the problem in the related art that the cold energy of the contaminated nitrogen gas discharged from the air separation process is not recovered and utilized, resulting in waste of cold energy of the contaminated nitrogen gas.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a gas processing device, including: an absorption tower, having a liquid inlet and a liquid outlet; a desorption tower, the desorption tower is connected to the liquid inlet through a lean liquid pipeline, and the desorption tower is connected to the liquid outlet through a rich liquid pipeline; an air separation device, having a discharge port; wherein a first heat exchanger is provided on the lean liquid pipeline, the discharge port is connected to the first heat exchanger through a first connecting pipeline, and the first heat exchanger can perform heat exchange treatment on the fluid in the lean liquid pipeline with the fluid in the first connecting pipeline.

[0006] Furthermore, the gas processing device also includes a conversion furnace and a second connecting pipeline. The conversion furnace is connected to the absorption tower. The conversion furnace has a coolant inlet and a coolant outlet. One end of the second connecting pipeline is connected to the coolant inlet, and the other end of the second connecting pipeline is connected to the coolant outlet. A second heat exchanger is arranged on the rich liquid pipeline. The second connecting pipeline is connected to the second heat exchanger. The second heat exchanger can perform heat exchange treatment on the fluid in the second connecting pipeline with the fluid in the rich liquid pipeline.

[0007] Furthermore, the gas processing device also includes a third connecting pipeline and a slag lock bucket connected to the third connecting pipeline, and the third connecting pipeline is connected to the first connecting pipeline through the first heat exchanger.

[0008] Furthermore, the gas processing device also includes a compressor arranged on the third connecting pipeline, the compressor is located upstream of the slag lock bucket, and the compressor can compress the gas in the third connecting pipeline.

[0009] Furthermore, the gas processing device also includes a cold energy recovery device arranged on the first connecting pipeline, and the cold energy recovery device can recover the cold energy of the fluid in the first connecting pipeline.

[0010] Furthermore, the cold recovery device is an adsorption refrigeration system or an air heat recovery device or a heat pipe heat recovery unit.

[0011] Furthermore, the gas processing device also includes a lean liquid pressure pump arranged on the lean liquid pipeline.

[0012] Further, the lean liquid booster pump is located upstream of the first heat exchanger.

[0013] Furthermore, the gas processing device also includes a rich liquid pressure pump arranged on the rich liquid pipeline.

[0014] Further, the rich liquid pressure pump is located upstream of the second heat exchanger.

[0015] Applying the technical solution of the present invention, the gas processing device includes: an absorption tower, a desorption tower and an air separation device. The absorption tower has a liquid inlet and a liquid outlet. The desorption tower is connected to the liquid inlet through a lean liquid pipeline, and the desorption tower is connected to the liquid outlet through a rich liquid pipeline. The air separation device has a discharge port. Among them, a first heat exchanger is arranged on the lean liquid pipeline, and the discharge port is connected to the first heat exchanger through a first connecting pipeline. The first heat exchanger can perform heat exchange treatment on the fluid in the lean liquid pipeline with the fluid in the first connecting pipeline. In this way, carbon dioxide and hydrogen are contained in the absorption tower, hydrogen is discharged from the top of the absorption tower, the lean liquid pipeline inputs low-temperature methanol lean liquid into the absorption tower to absorb carbon dioxide, and the methanol rich liquid that absorbs carbon dioxide is discharged from the rich liquid pipeline, and the carbon dioxide in the methanol rich liquid is released and extracted in the desorption tower. The dirty nitrogen gas discharged from the air separation device can be discharged from the discharge port and enter the first connecting pipeline, and the first heat exchanger on the first connecting pipeline absorbs the coldness of the dirty nitrogen gas in the first connecting pipeline. The first heat exchanger transfers the cold of the contaminated nitrogen gas absorbed to the lean liquid pipeline, so as to reduce the temperature of the methanol lean liquid in the lean liquid pipeline, so as to improve the adsorption capacity of the methanol lean liquid for carbon dioxide. In this way, the cold of the contaminated nitrogen gas discharged from the air separation unit can be recycled, avoiding the problem of waste of cold of the contaminated nitrogen gas. Therefore, the technical solution of the present application effectively solves the problem in the related art that the cold of the contaminated nitrogen gas discharged from the air separation process is not recycled, resulting in waste of cold of the contaminated nitrogen gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1A schematic diagram of pipeline connections of an embodiment of a gas processing device according to the present invention is shown.

[0018] The above drawings include the following reference numerals:

[0019] 10. Absorption tower; 20. Desorption tower; 30. Air separation unit; 40. Shift furnace;

[0020] 50. lean liquid pipeline; 51. first heat exchanger; 52. lean liquid booster pump;

[0021] 60. Rich liquid pipeline; 61. Rich liquid booster pump; 62. Second heat exchanger;

[0022] 70. First connecting pipeline; 71. Cold recovery device;

[0023] 80. A second connecting pipeline;

[0024] 90. A third connecting pipeline; 91. A compressor. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0027] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0028] In this embodiment, if Figure 1 As shown, the gas processing device includes: an absorption tower 10, a desorption tower 20 and an air separation device 30. The absorption tower 10 has a liquid inlet and a liquid outlet. The desorption tower 20 is connected to the liquid inlet through a lean liquid pipeline 50, and the desorption tower 20 is connected to the liquid outlet through a rich liquid pipeline 60. The air separation device 30 has a discharge port. Among them, a first heat exchanger 51 is provided on the lean liquid pipeline 50, and the discharge port is connected to the first heat exchanger 51 through a first connecting pipeline 70. The first heat exchanger 51 can perform heat exchange treatment on the fluid in the lean liquid pipeline 50 and the fluid in the first connecting pipeline 70.

[0029] In this way, the absorption tower 10 contains carbon dioxide and hydrogen, and the hydrogen is discharged from the top of the absorption tower 10. The lean liquid pipeline 50 inputs the low-temperature methanol lean liquid into the absorption tower 10 to absorb carbon dioxide, and the methanol rich liquid that absorbs carbon dioxide is discharged from the rich liquid pipeline 60, and the carbon dioxide in the methanol rich liquid is released and extracted in the desorption tower 20. The dirty nitrogen gas discharged from the air separation unit 30 can be discharged from the discharge port and enter the first connecting pipeline 70. The first heat exchanger 51 on the first connecting pipeline 70 absorbs the cold of the dirty nitrogen gas in the first connecting pipeline 70. The first heat exchanger 51 transfers the cold of the absorbed dirty nitrogen gas to the lean liquid pipeline 50, which is convenient for reducing the temperature of the methanol lean liquid in the lean liquid pipeline 50 to improve the adsorption capacity of the methanol lean liquid for carbon dioxide. In this way, the cold of the dirty nitrogen gas discharged from the air separation unit 30 can be recycled and utilized, avoiding the problem of waste of cold of the dirty nitrogen gas. Therefore, the technical solution of this embodiment effectively solves the problem in the related art that the cooling capacity of the contaminated nitrogen gas discharged from the air separation process is not recovered and utilized, resulting in a waste of cooling capacity of the contaminated nitrogen gas.

[0030] like Figure 1As shown, the gas processing device also includes a conversion furnace 40 and a second connecting pipeline 80, and the conversion furnace 40 is connected to the absorption tower 10. The conversion furnace 40 has a coolant inlet and a coolant outlet. One end of the second connecting pipeline 80 is connected to the coolant inlet, and the other end of the second connecting pipeline 80 is connected to the coolant outlet. A second heat exchanger 62 is provided on the rich liquid pipeline 60, and the second connecting pipeline 80 is connected to the second heat exchanger 62. The second heat exchanger 62 can perform heat exchange treatment on the fluid in the second connecting pipeline 80 and the fluid in the rich liquid pipeline 60. In this embodiment, a water-gas shift reaction occurs in the conversion furnace 40, and hydrogen and carbon dioxide are produced from a gas mixture containing carbon monoxide and water vapor. This reaction is an exothermic reaction, and a coolant needs to be introduced into the conversion furnace 40 to reduce the temperature in the conversion furnace 40 and maintain the normal progress of the water-gas shift reaction. Since the methanol rich liquid in the rich liquid pipeline 60 needs to be heated up to release carbon dioxide after entering the desorption tower 20, a second heat exchanger 62 is provided on the rich liquid pipeline 60 so that the second heat exchanger 62 can absorb a portion of the cold energy of the methanol rich liquid in the rich liquid pipeline 60. The second heat exchanger 62 transfers the cold energy to the second connecting pipeline 80 so that the coolant in the second connecting pipeline 80 can be cooled down and returned to the conversion furnace 40 for cooling. In addition, the temperature of the coolant discharged from the conversion furnace 40 is relatively high, which can increase the temperature of the methanol rich liquid in the rich liquid pipeline 60, so as to facilitate the precipitation of carbon dioxide in the methanol rich liquid, reduce the setting of additional heat sources, and reduce energy waste. The above-mentioned setting further recycles cold energy and reduces the waste of cold energy of polluted nitrogen gas.

[0031] like Figure 1 As shown, the gas processing device further includes a third connecting pipeline 90 and a slag lock bucket connected to the third connecting pipeline 90 . The third connecting pipeline 90 is connected to the first connecting pipeline 70 through the first heat exchanger 51 .

[0032] In this embodiment, the slag lock bucket mainly serves to receive the ash discharged from the gasifier and discharge the ash. Under the control of the slag discharge system logic program, the slag lock bucket completes the slag collection and discharge operations through the steps of slag collection, pressure relief, flushing, slag discharge, and pressure increase. The third connecting pipeline 90 is connected to the first connecting pipeline 70 through the first heat exchanger 51, so that the contaminated nitrogen gas after the cold is recovered can be rushed into the slag lock bucket for pressure increase operation, so that the ash can be discharged smoothly, and the contaminated nitrogen gas is further recycled.

[0033] In this embodiment, the dirty nitrogen gas that has been recovered through the first heat exchanger 51 and has been raised in temperature will be guided to the slag lock bucket and used as a gas source for boosting, thereby further recycling the dirty nitrogen gas and reducing the waste of the dirty nitrogen gas. After the heat exchange treatment of the first heat exchanger 51, the temperature of the dirty nitrogen gas will increase, but it can still be used as a cheap gas source for the boosting operation of the slag lock bucket. In this way, the cold energy of the dirty nitrogen gas discharged from the air separation unit is utilized, and the use of additional energy or gas for boosting the slag lock bucket is avoided. Therefore, the first heat exchanger 51 is connected to the slag lock bucket through the third connecting pipeline 90, which realizes the recovery of cold energy and the reuse of gas, and improves the energy efficiency and environmental protection performance of the entire system.

[0034] like Figure 1 As shown, the gas processing device further includes a compressor 91 disposed on the third connecting pipeline 90. The compressor 91 is located upstream of the slag lock bucket, and the compressor 91 can compress the gas in the third connecting pipeline 90. The compressor 91 compresses the dirty nitrogen gas after heat exchange to increase the pressure of the dirty nitrogen gas, so as to facilitate the introduction of the dirty nitrogen gas into the slag lock bucket for the pressure-boosting operation of the slag lock bucket.

[0035] like Figure 1 As shown, the gas processing device further includes a cold recovery device 71 disposed on the first connecting pipeline 70, and the cold recovery device 71 can recover the cold of the fluid in the first connecting pipeline 70. The setting of the cold recovery device 71 can recover part of the cold of the contaminated nitrogen gas to control the cold received by the first heat exchanger 51, thereby avoiding waste of the cold of the contaminated nitrogen gas.

[0036] In this embodiment, the cooling capacity of the contaminated nitrogen gas discharged from the air separation device 30 is relatively large, which is greater than the cooling capacity required for cooling the lean methanol liquid in the lean liquid pipeline 50. Therefore, a cooling capacity recovery device 71 is provided to recover and reuse the cooling capacity of the contaminated nitrogen gas discharged from the air separation device 30.

[0037] like Figure 1 As shown, the cold recovery device 71 is an adsorption refrigeration system or an air heat recovery device or a heat pipe heat recovery unit. The above configuration enables the cold recovery device 71 to recover and reuse part of the cold of the contaminated nitrogen gas discharged from the air separation device 30.

[0038] Among them, the adsorption refrigeration system includes an adsorbent container, a heat exchanger and a desorber. The heat exchanger of the adsorption refrigeration system is connected to the first connecting pipe 70 to absorb the cold in the dirty nitrogen gas. The adsorbent container is connected to the lean liquid pipeline 50 or other systems that require cold. When the heat in the system is absorbed by the adsorbent, the adsorbent container will release the previously stored cold. In the adsorption stage, the heat exchanger absorbs cold from the dirty nitrogen gas to cool the adsorbent, such as silica gel, activated alumina, etc. In the desorption stage, the adsorbent is heated, such as using low-grade thermal energy, to release the previously absorbed moisture or other adsorbents. The heat released in this process can be recycled, and the adsorbent can re-absorb heat after being cooled again to achieve the recycling of cold.

[0039] Among them, the heat exchanger of the air heat recovery equipment is connected to the first connecting pipe 70 to recover the cold energy in the dirty nitrogen gas. The fan or blower of the air heat recovery equipment pushes the air through the heat exchanger, and the air will pass through the filter to remove impurities before entering the heat exchanger. The other side of the air heat recovery equipment is connected to a system that requires preheating of air, such as a preheating furnace, an air conditioning system or a drying equipment. The dirty nitrogen gas enters the heat exchanger of the air heat recovery equipment through the first connecting pipe 70 and exchanges heat with the air. The air absorbs cold energy from the dirty nitrogen gas, and after being precooled, it can be used for subsequent cold energy utilization, such as cooling other fluids or spaces. The fan or blower ensures a sufficiently high flow rate between the air and the dirty nitrogen gas to improve the heat exchange efficiency. The filter prevents impurities from entering the heat exchanger to avoid a decrease in the heat exchange efficiency.

[0040] The heat pipe heat recovery unit includes a heat pipe, a hot end heat exchanger at one end of the heat pipe, and a cold end heat exchanger at the other end of the heat pipe. The hot end heat exchanger is connected to the first connecting pipe 70, and the cold end heat exchanger is connected to other systems that require cooling. The first connecting pipe 70 is connected to the hot end heat exchanger so that the cooling in the dirty nitrogen can be absorbed by the hot end of the heat pipe. The hot end heat exchanger absorbs cooling from the dirty nitrogen, causing the working fluid inside the heat pipe, such as water, ammonia or Freon, to evaporate. The working fluid vapor flows to the cold end heat exchanger through the capillary action or gravity inside the heat pipe. At this time, the steam condenses and releases cooling to the lean liquid or other systems for precooling or lowering the temperature of the system. After releasing the cooling, the working fluid liquid phase returns to the hot end heat exchanger through the heat pipe again, repeating the heat absorption and cooling process to achieve continuous recovery and reuse of cooling.

[0041] like Figure 1 As shown, the gas processing device further includes a lean liquid pressure pump 52 disposed on the lean liquid pipeline 50. The arrangement of the lean liquid pressure pump 52 facilitates the transportation of the methanol lean liquid in the lean liquid pipeline 50.

[0042] like Figure 1As shown, the lean liquid booster pump 52 is located upstream of the first heat exchanger 51. In this way, the heat exchange efficiency of the methanol lean liquid during heat exchange in the first heat exchanger 51 is improved, and the flow velocity and pressure of the methanol lean liquid in the first heat exchanger 51 are increased.

[0043] like Figure 1 As shown, the gas processing device further includes a rich liquid pressure pump 61 disposed on the rich liquid pipeline 60. The rich liquid pressure pump 61 is disposed to facilitate the transportation of the methanol rich liquid in the rich liquid pipeline 60.

[0044] like Figure 1 As shown, the rich liquid booster pump 61 is located upstream of the second heat exchanger 62. In this way, the heat exchange efficiency of the methanol rich liquid in the second heat exchanger 62 is improved, and the flow velocity and pressure of the methanol rich liquid in the second heat exchanger 62 are increased.

[0045] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0046] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0047] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gas processing device, characterized in that: include: An absorption tower (10) having a liquid inlet and a liquid outlet; a desorption tower (20), wherein the desorption tower (20) is connected to the liquid inlet via a lean liquid pipeline (50), and the desorption tower (20) is connected to the liquid outlet via a rich liquid pipeline (60); An air separation unit (30) having a discharge port; The lean liquid pipeline (50) is provided with a first heat exchanger (51), the discharge port is connected to the first heat exchanger (51) via a first connecting pipeline (70), and the first heat exchanger (51) can perform heat exchange processing between the fluid in the lean liquid pipeline (50) and the fluid in the first connecting pipeline (70).

2. The gas processing device according to claim 1, characterized in that: The gas processing device further comprises a conversion furnace (40) and a second connecting pipeline (80). The conversion furnace (40) is connected to the absorption tower (10). The conversion furnace (40) has a cooling liquid inlet and a cooling liquid outlet. One end of the second connecting pipeline (80) is connected to the cooling liquid inlet, and the other end of the second connecting pipeline (80) is connected to the cooling liquid outlet. A second heat exchanger (62) is arranged on the rich liquid pipeline (60). The second connecting pipeline (80) is connected to the second heat exchanger (62). The second heat exchanger (62) can perform heat exchange treatment between the fluid in the second connecting pipeline (80) and the fluid in the rich liquid pipeline (60).

3. The gas processing device according to claim 1, characterized in that: The gas processing device further comprises a third connecting pipeline (90) and a slag lock bucket connected to the third connecting pipeline (90); the third connecting pipeline (90) is connected to the first connecting pipeline (70) via the first heat exchanger (51).

4. The gas processing device according to claim 3, characterized in that: The gas processing device further comprises a compressor (91) arranged on the third connecting pipeline (90), wherein the compressor (91) is located upstream of the slag lock bucket, and the compressor (91) is capable of compressing the gas in the third connecting pipeline (90).

5. The gas processing device according to claim 1, characterized in that: The gas processing device further comprises a cold energy recovery device (71) arranged on the first connecting pipeline (70), and the cold energy recovery device (71) is capable of recovering the cold energy of the fluid in the first connecting pipeline (70).

6. The gas processing device according to claim 5, characterized in that: The cold recovery device (71) is an adsorption refrigeration system or an air heat recovery device or a heat pipe heat recovery unit.

7. The gas processing device according to claim 1, characterized in that: The gas processing device further comprises a lean liquid pressure pump (52) arranged on the lean liquid pipeline (50).

8. The gas processing device according to claim 7, characterized in that: The lean liquid booster pump (52) is located upstream of the first heat exchanger (51).

9. The gas processing device according to claim 2, characterized in that: The gas processing device further comprises a rich liquid pressurizing pump (61) arranged on the rich liquid pipeline (60).

10. The gas processing device according to claim 9, characterized in that: The rich liquid pressurizing pump (61) is located upstream of the second heat exchanger (62).

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