Device for separating carbon and nitrogen from tail gas of BDO converter by using alkyne-aldehyde method

Abstract

The utility model provides an alkyne-aldehyde method BDO converter tail gas carbon nitrogen separation device, relates to the technical field of gas separation, the separation device comprises a waste heat recovery device, a drying device and a PSA carbon nitrogen separation device which are connected in series, the drying device comprises a gas-liquid separation tank and a dehydration device which are connected in series, the dehydration device comprises a first drying tower and a second drying tower which are arranged in parallel, and the first drying tower and the second drying tower use cold fluid of the waste heat recovery device as a drying agent regeneration heat source. The tail gas of the converter is cooled through the waste heat recovery device, and then is dehydrated through the gas-liquid separator and the dehydration device, so that the dew point of the tail gas of the converter is reduced to-70 DEG C, and sufficient dehydration is realized; the drying agent in the dehydration device is regenerated by using heat of the tail gas of the converter, additional energy consumption is not needed, and the problems that the tail gas of the BDO converter in the alkyne-aldehyde method is high in cost and cannot be applied to the industry during resource utilization are solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas separation, and in particular relates to a carbon-nitrogen separation device for tail gas of a BDO converter using an acetylene-aldehyde process. Background Art

[0002] 1,4-Butanediol (BDO) is an important chemical widely used in industry, medicine and other fields. There are many methods to synthesize BDO, among which the acetylene aldehyde method is the most commonly used BDO production process in industry.

[0003] The main components of the tail gas from the converter in the BDO production process using the acetylene aldehyde method are 18-20% carbon dioxide, 61-63% nitrogen, 1-2% oxygen, and 16-18% water. The tail gas contains abundant carbon dioxide and nitrogen resources, and direct discharge will cause waste of resources and environmental pollution. However, the tail gas of the reformer of BDO in the acetylene-aldehyde process also contains a high proportion of water, and the moisture content is much higher than that of general coal-fired boiler flue gas. Since the PSA adsorbent has a stronger affinity for water than for carbon dioxide and nitrogen, the moisture will be adsorbed by the adsorbent first, reducing the adsorption efficiency of the adsorbent for carbon dioxide and nitrogen. Before separating nitrogen and carbon dioxide, the tail gas of the reformer needs to be fully dried. Since the specific heat capacity and phase change enthalpy of water are very large, when the existing equipment is used to separate the tail gas of the reformer, these moisture will absorb a large amount of heat, resulting in a significant increase in process energy consumption and operating costs. The value of the recovered carbon dioxide and nitrogen cannot even cover the operating investment cost. Moreover, the one-time investment for the construction of the equipment also requires a large amount of funds, resulting in the economic dissipation of nitrogen and carbon dioxide produced by the tail gas of the reformer, and they are generally discharged directly through the chimney through the induced draft fan.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The utility model aims to provide a carbon-nitrogen separation device for tail gas of BDO converter by acetylene-aldehyde process, which can remove a large amount of water contained in the tail gas of converter with relatively low energy consumption. The tail gas of converter after drying can be used to prepare high-purity nitrogen and carbon dioxide, so as to solve the problem that the tail gas of BDO converter by acetylene-aldehyde process is difficult to be utilized as a resource.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A carbon-nitrogen separation device for tail gas of a BDO converter by an acetylene-aldehyde process comprises a waste heat recovery device, a drying device, and a PSA carbon-nitrogen separation device arranged in series, wherein the drying device comprises a gas-liquid separation tank and a dehydration device arranged in series, wherein the dehydration device comprises a first drying tower and a second drying tower arranged in parallel, wherein the first drying tower and the second drying tower are filled with a desiccant, wherein the gas discharged from the gas-liquid separation tank selectively enters the first drying tower or the second drying tower, and the first drying tower and the second drying tower use a cold fluid of the waste heat recovery device as a desiccant regeneration heat source.

[0008] Preferably, a first fan is provided between the gas phase outlet of the gas-liquid separation tank and the first drying tower and the second drying tower, and the outlet pipeline of the first fan is divided into two paths and respectively connected to the bottom of the first drying tower and the second drying tower.

[0009] Preferably, the waste heat recovery device comprises a first heat exchanger and a second fan. The waste heat recovery device uses air as a cold fluid. The cold fluid discharged from the waste heat recovery device is transported to the first drying tower or the second drying tower via the second fan.

[0010] Preferably, a first air intake valve is provided on the pipeline connecting the first fan to the first drying tower, and a second air intake valve is provided on the pipeline connecting the first fan to the second drying tower, and the first air intake valve and the second air intake valve are connected in parallel.

[0011] Preferably, the outlet pipeline of the second fan is divided into two routes and respectively connected to the top of the first drying tower and the top of the second drying tower.

[0012] Preferably, a third air inlet valve is provided on the pipeline connecting the second fan to the first drying tower, and a fourth air inlet valve is provided on the pipeline connecting the second fan to the second drying tower, and the third air inlet valve and the fourth air inlet valve are connected in parallel.

[0013] Preferably, the top of the first drying tower is connected to the PSA carbon-nitrogen separation device, and a first exhaust valve is provided on the pipeline connecting the first drying tower and the PSA carbon-nitrogen separation device, the top of the second drying tower is connected to the PSA carbon-nitrogen separation device, and a second exhaust valve is provided on the pipeline connecting the second drying tower and the PSA carbon-nitrogen separation device, and the first exhaust valve and the second exhaust valve are connected in parallel.

[0014] Preferably, the bottoms of the first drying tower and the second drying tower are connected to an exhaust device, a third exhaust valve is provided on the pipeline connecting the first drying tower and the exhaust device, and a fourth exhaust valve is provided on the pipeline connecting the second drying tower and the exhaust device, and the third exhaust valve and the fourth exhaust valve are connected in parallel.

[0015] Preferably, it further comprises a second heat exchanger, wherein the second heat exchanger is located between the first fan and the dehydration device.

[0016] Preferably, the exhaust device is a muffler.

[0017] Beneficial effects:

[0018] (1) The utility model cools the tail gas of the converter through a waste heat recovery device, so that most of the water vapor therein is condensed and liquefied, and then removed through a gas-liquid separator. The preliminarily dried tail gas of the converter enters a dehydration device and is further dried by a desiccant, so that the dew point of the tail gas of the converter leaving the dehydration device can be reduced to -70°C, thereby fully removing the moisture in the tail gas of the converter; the desiccant in the dehydration device is purged and regenerated using the hot air generated by the waste heat recovery device, without the need for additional energy consumption, thereby greatly reducing the energy consumption when drying the tail gas of the converter. The desiccant used can also be continuously regenerated, so that the operating cost is controlled at a low level, thereby solving the problem that the cost of resource utilization of the tail gas of the BDO converter of the converter acetylene-aldehyde process is high and cannot be used in the industry;

[0019] (2) The utility model also sets a second heat exchanger downstream of the first fan. After the first fan works on the flue gas, the flue gas temperature rises. The heated flue gas is used to reheat the air discharged by the second fan, so that part of the power consumption of the first fan is converted into thermal energy of the air. The thermal energy is used to regenerate the desiccant, avoiding energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. Among them:

[0021] Figure 1 A flow chart of an acetylene-aldehyde process BDO converter tail gas separation device provided in an embodiment of the utility model;

[0022] Figure 2 A flow chart of a dehydration device provided by an embodiment of the utility model;

[0023] Figure 3 A flow chart with a second heat exchanger provided for another embodiment of the utility model;

[0024] Figure 4 A flow chart of a nitrogen and carbon dioxide refining device provided downstream of a PSA carbon-nitrogen separation device according to an embodiment of the utility model;

[0025] In the figure: 1. waste heat recovery device; 2. PSA carbon-nitrogen separation device; 3. gas-liquid separation tank; 4. dehydration device; 5. nitrogen refining device; 6. carbon dioxide refining device; 101. first heat exchanger; 102. second fan; 103. second heat exchanger; 401. first drying tower; 402. second drying tower; 403. first fan; 404a. first air inlet valve; 404b. second air inlet valve; 404c. third air inlet valve; 404d. fourth air inlet valve; 405a. first exhaust valve; 405b. second exhaust valve; 405c. third exhaust valve; 405d. fourth exhaust valve. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features.

[0029] In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be internal connection between two elements, indirect connection, or an interactive relationship between two elements.

[0030] The present invention will be described in detail below in conjunction with the embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0031] Aiming at the problem that tail gas of a BDO converter by an acetylene-aldehyde process is difficult to recycle, the utility model provides a tail gas carbon-nitrogen separation device of a BDO converter by an acetylene-aldehyde process, comprising a waste heat recovery device 1, a drying device, and a PSA carbon-nitrogen separation device 2 which are arranged in series. The tail gas of the converter with a high moisture content is dried so that it can meet the feed requirements of the PSA carbon-nitrogen separation device 2, and then high-purity nitrogen and carbon dioxide are obtained through a pressure swing adsorption process. The drying process does not generate additional energy consumption, and only a small amount of power consumption is generated. The utility model has the advantages of simple device structure and low investment and operation costs, thereby significantly reducing the processing cost of the tail gas of the BDO converter by an acetylene-aldehyde process, so that the tail gas can be recycled.

[0032] like Figure 1 As shown, the drying device includes a gas-liquid separation tank 3 and a dehydration device 4 arranged in series. After the tail gas of the reformer leaves the waste heat recovery device 1 and is cooled, a large amount of water vapor is condensed and liquefied, and enters the gas-liquid separation tank 3 for separation. After drying, the tail gas of the reformer leaves from the top of the gas-liquid separation tank 3 and enters the dehydration device 4 for secondary drying. The dehydration device 4 includes a first drying tower 401 and a second drying tower 402 arranged in parallel. The first drying tower 401 and the second drying tower 402 are filled with desiccants. The tail gas of the reformer with water vapor is fully dehydrated when passing through the desiccant. Dehydration, the gas discharged from the gas-liquid separation tank 3 enters the first drying tower 401 or the second drying tower 402, that is, the first drying tower 401 and the second drying tower 402 do not work at the same time, but are standby for each other. When the tail gas of the converter enters the first drying tower 401 for drying, the second drying tower 402 regenerates the desiccant. After the regeneration is completed, the tail gas of the converter is passed into the second drying tower 402 for drying. At the same time, the first drying tower 401 starts to regenerate the desiccant to achieve continuous drying of the tail gas of the converter and continuous regeneration of the desiccant, so that the device can achieve continuous operation.

[0033] The first drying tower 401 and the second drying tower 402 use the cold fluid of the waste heat recovery device 1 as the heat source for desiccant regeneration. Based on this, the waste heat recovery device 1 not only cools the tail gas of the converter to liquefy and condense most of the water therein, but also utilizes the recovered heat to regenerate the desiccant, thereby realizing the recycling of the desiccant without consuming external heat sources, and significantly reducing the energy consumption when drying the tail gas of the converter.

[0034] A first fan 403 is provided between the gas phase outlet of the gas-liquid separation tank 3 and the first drying tower 401 and the second drying tower 402. The outlet pipeline of the first fan 403 is divided into two routes and respectively connected to the bottom of the first drying tower 401 and the second drying tower 402, providing power for the drying device and the feed of the downstream PSA carbon-nitrogen separation device 2.

[0035] In a preferred embodiment of the utility model, the waste heat recovery device 1 includes a first heat exchanger 101 and a second fan 102, wherein the first heat exchanger 101 uses air as a cold fluid to cool the converter exhaust gas flowing through the first heat exchanger 101, so that the temperature of the converter exhaust gas leaving the first heat exchanger 101 is reduced to below 45°C, and the cooled converter exhaust gas is transported to the first drying tower 401 or the second drying tower 402 via the second fan 102 for secondary drying treatment.

[0036] The first heat exchanger 101 can adopt a shell and tube heat exchanger, a plate heat exchanger and a fin heat exchanger. Generally, the relatively higher temperature reformer exhaust gas can enter from the tube side inlet of the first heat exchanger 101 and be discharged from the tube side outlet after cooling. At this time, the air used for cooling enters from the shell side inlet of the first heat exchanger 101 and is discharged from the tube side outlet, thereby fully utilizing the heat of the reformer exhaust gas to heat the air and reducing the heat loss through the shell of the first heat exchanger 101. However, it is not limited to the above-mentioned heat exchange method. For example, the reformer exhaust gas can also flow through the shell side of the first heat exchanger 101. At this time, the relatively lower temperature air enters from the tube side and is discharged from the tube side outlet after heating.

[0037] like Figure 2 As shown, in a preferred embodiment of the utility model, a first air intake valve 404a is provided on the pipeline connecting the first fan 403 to the first drying tower 401, and a second air intake valve 404b is provided on the pipeline connecting the first fan 403 to the second drying tower 402, and the first air intake valve 404a and the second air intake valve 404b are connected in parallel; at the same time, only one of the first air intake valve 404a and the second air intake valve 404b is in an open state. When the first fan 403 is connected to the first drying tower 401, the first air intake valve 404a is in an open state, and the second air intake valve 404b is in a closed state, so that the tail gas of the converter flows from the first fan 403 to the first drying tower 401; when the first fan 403 is connected to the second drying tower 402, the second air intake valve 404b is in an open state, and the first air intake valve 404a is in a closed state, so that the tail gas of the converter flows from the first fan 403 to the second drying tower 402.

[0038] like Figure 2As shown, the outlet pipeline of the second fan 102 is divided into two routes and connected to the top of the first drying tower 401 and the top of the second drying tower 402 respectively. Specifically, a third air intake valve 404c is provided on the pipeline connecting the second fan 102 to the first drying tower 401, and a fourth air intake valve 404d is provided on the pipeline connecting the second fan 102 to the second drying tower 402. The third air intake valve 404c and the fourth air intake valve 404d are connected in parallel. At the same time, only one of the third air intake valve 404c and the fourth air intake valve 404d is in the open state. When the second fan 102 is connected to the first drying tower 401, the third air intake valve 404c and the fourth air intake valve 404d are in the open state. When the second fan 102 is connected to the second drying tower 402, the third air intake valve 404c is in a closed state, and the fourth air intake valve 404d is in a closed state, so that the air heated by the first heat exchanger 101 enters the first drying tower 401, and the desiccant in the first drying tower 401 is purged and regenerated; when the second fan 102 is connected to the second drying tower 402, the third air intake valve 404c is in a closed state, and the fourth air intake valve 404d is in an open state, so that the air heated by the first heat exchanger 101 enters the second drying tower 402, and the desiccant in the second drying tower 402 is purged and regenerated.

[0039] like Figure 2 As shown, the top of the first drying tower 401 is connected to the PSA carbon-nitrogen separation device 2, and a first exhaust valve 405a is provided on the pipeline connecting the first drying tower 401 and the PSA carbon-nitrogen separation device 2, the top of the second drying tower 402 is connected to the PSA carbon-nitrogen separation device 2, and a second exhaust valve 405b is provided on the pipeline connecting the second drying tower 402 and the PSA carbon-nitrogen separation device 2, the first exhaust valve 405a and the second exhaust valve 405b are connected in parallel, and are respectively used to control the on and off of the first drying tower 401, the second drying tower 402 and the downstream PSA carbon-nitrogen separation device 2, and at the same time, only one of the first exhaust valve 405a and the second exhaust valve 405b is in an open state.

[0040] like Figure 2 As shown, the bottoms of the first drying tower 401 and the second drying tower 402 are both connected to the exhaust device, a third exhaust valve 405c is provided on the pipeline connecting the first drying tower 401 and the exhaust device, and a fourth exhaust valve 405d is provided on the pipeline connecting the second drying tower 402 and the exhaust device. The third exhaust valve 405c and the fourth exhaust valve 405d are connected in parallel, and are respectively used to control the on-off of the first drying tower 401, the second drying tower 402 and the exhaust device.

[0041] The exhaust device is a silencer, which is used to discharge the gas in the drying tower when the first drying tower 401 or the second drying tower 402 uses the hot air exhausted by the second fan 102 to regenerate the adsorbent, and plays a noise reduction role to reduce the airflow noise at the exhaust pipeline outlet.

[0042] When the first drying tower 401 is used to dry the tail gas of the reformer, the first air inlet valve 404a and the first exhaust valve 405a are opened, and the second air inlet valve 404b and the second exhaust valve 405b are closed, so that the first fan 403, the first drying tower 401 and the downstream PSA carbon-nitrogen separation device 2 are connected. At this time, the tail gas of the reformer separated by the gas-liquid separation tank 3 enters from the bottom of the first drying tower 401, is discharged from the first exhaust valve 405a at the top of the tower after drying, and enters the downstream PSA carbon-nitrogen separation device 2. The nitrogen separation device 2 produces nitrogen and carbon dioxide; at the same time, the third air inlet valve 404c and the third exhaust valve 405c are closed, and the fourth air inlet valve 404d and the fourth exhaust valve 405d are opened, so that the second fan 102, the second drying tower 402 and the exhaust device are connected, and the air heated by the first heat exchanger 101 is used to purge the desiccant in the second drying tower 402, and the heat of the hot air is used to evaporate the moisture adsorbed by the desiccant and be discharged from the exhaust device with the air flow, so as to realize the regeneration of the desiccant.

[0043] When the desiccant regeneration in the second drying tower 402 is completed, the open / closed state of the first air intake valve 404a, the first exhaust valve 405a, the second air intake valve 404b, the second exhaust valve 405b, the third air intake valve 404c, the third exhaust valve 405c, the fourth air intake valve 404d and the fourth exhaust valve 405d can be switched, so that the first drying tower 401 enters the desiccant regeneration condition, and the second drying tower 402 enters the converter tail gas drying condition, so that the converter tail gas drying process and the desiccant regeneration process do not interfere with each other, thereby realizing the continuous production of the converter tail gas drying process and providing a stable gas source for the downstream PSA carbon-nitrogen separation device 2.

[0044] The first fan 403 and the second fan 102 can be atmospheric pressure fans or booster fans, both of which can meet the needs of the drying device and the downstream PSA carbon-nitrogen separation device 2 for gas source flow and pressure.

[0045] In addition, if Figure 3 As shown, when the first fan 403 adopts a booster fan, the first fan 403 does work on the flue gas, thereby increasing its kinetic energy and internal energy and raising its temperature. In order to utilize this part of heat, a second heat exchanger 103 is arranged between the first fan 403 and the dehydration device 4, so that the flue gas exhausted by the first fan 403 and the air exhausted by the second fan 102 can exchange heat, so that the air temperature can be further increased, thereby improving the regeneration efficiency of the desiccant.

[0046] In the utility model, the desiccant is selected from commercially available 13X molecular sieves, and other commercially available brands of desiccant may also be used.

[0047] After the tail gas of the BDO converter of the acetylene-formaldehyde process is treated by the gas-liquid separation tank 3 and the drying device, its dew point can be reduced to -70°C, which can fully meet the water content requirement of the downstream PSA carbon-nitrogen separation device 2 for the raw gas.

[0048] The converter tail gas treated by the drying device can meet the feed requirements of most existing PSA carbon-nitrogen separation devices. Therefore, the PSA carbon-nitrogen separation device 2 in the utility model can adopt the existing common carbon-nitrogen separation device, or it can adopt the device for producing nitrogen and carbon dioxide using flue gas as disclosed in the patent documents CN216404319U, CN113975950A, and CN114857856A. Based on actual needs, technicians in this field can make routine changes to these devices, and these changes should not be regarded as departing from the protection scope of the technical solution of this application.

[0049] In addition, if Figure 4 As shown, a nitrogen refining device 5 and a carbon dioxide refining device 6 can be further provided at the nitrogen outlet and the carbon dioxide outlet of the PSA carbon-nitrogen separation device 2, respectively, to further purify the nitrogen and carbon dioxide produced by the PSA carbon-nitrogen separation device 2 to obtain higher quality nitrogen and carbon dioxide products.

[0050] In summary:

[0051] The utility model can fully remove most of the water in the tail gas of the BDO converter by cooling, gas-liquid separation and desiccant adsorption of the tail gas of the acetylene-aldehyde process. The dew point can be reduced to -70°C, which fully meets the feeding requirements of the PSA carbon-nitrogen separation device 2. The desiccant in the dehydration device 4 is purged and regenerated using the hot air generated by the waste heat recovery device 1, without the need for additional energy consumption, thereby greatly reducing the energy consumption when drying the tail gas of the converter. The desiccant used can also be continuously regenerated, so that the operating cost is controlled at a low level, thereby solving the problem that the tail gas of the BDO converter of the acetylene-aldehyde process is high in cost when being utilized as a resource and cannot be applied in the industry.

[0052] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A carbon-nitrogen separation device for tail gas of BDO converter using an acetylene-aldehyde process, characterized in that: It includes a waste heat recovery device, a drying device, and a PSA carbon-nitrogen separation device arranged in series. The drying device includes a gas-liquid separation tank and a dehydration device arranged in series. The dehydration device includes a first drying tower and a second drying tower arranged in parallel. The first drying tower and the second drying tower are filled with desiccant. The gas discharged from the gas-liquid separation tank selectively enters the first drying tower or the second drying tower. The first drying tower and the second drying tower use the cold fluid of the waste heat recovery device as a desiccant regeneration heat source.

2. The carbon-nitrogen separation device for tail gas of BDO converter in the acetylene-aldehyde process according to claim 1, characterized in that: A first fan is provided between the gas phase outlet of the gas-liquid separation tank and the first drying tower and the second drying tower. The outlet pipeline of the first fan is divided into two paths and respectively connected to the bottom of the first drying tower and the second drying tower.

3. The carbon-nitrogen separation device for tail gas of BDO converter using acetylene-aldehyde process according to claim 1, characterized in that: The waste heat recovery device comprises a first heat exchanger and a second fan. The waste heat recovery device uses air as a cold fluid. The cold fluid discharged from the waste heat recovery device is transported to the first drying tower or the second drying tower via the second fan.

4. The carbon-nitrogen separation device for tail gas of BDO converter using acetylene-aldehyde process according to claim 2, characterized in that: A first air inlet valve is provided on the pipeline connecting the first fan to the first drying tower, and a second air inlet valve is provided on the pipeline connecting the first fan to the second drying tower. The first air inlet valve and the second air inlet valve are connected in parallel.

5. The carbon-nitrogen separation device for tail gas of BDO converter using acetylene-aldehyde process according to claim 3, characterized in that: The outlet pipeline of the second fan is divided into two routes and respectively connected to the top of the first drying tower and the top of the second drying tower.

6. The carbon-nitrogen separation device for tail gas of BDO converter in the acetylene-aldehyde process according to claim 5, characterized in that: A third air inlet valve is provided on the pipeline connecting the second fan to the first drying tower, and a fourth air inlet valve is provided on the pipeline connecting the second fan to the second drying tower. The third air inlet valve and the fourth air inlet valve are connected in parallel.

7. The carbon-nitrogen separation device for tail gas of BDO converter using an acetylene-aldehyde process according to any one of claims 1 to 5, characterized in that: The top of the first drying tower is connected to the PSA carbon-nitrogen separation device, and a first exhaust valve is provided on the pipeline connecting the first drying tower and the PSA carbon-nitrogen separation device. The top of the second drying tower is connected to the PSA carbon-nitrogen separation device, and a second exhaust valve is provided on the pipeline connecting the second drying tower and the PSA carbon-nitrogen separation device. The first exhaust valve and the second exhaust valve are connected in parallel.

8. The carbon-nitrogen separation device for tail gas of BDO converter using an acetylene-aldehyde process according to any one of claims 1 to 5, characterized in that: The bottoms of the first drying tower and the second drying tower are both connected to an exhaust device, a third exhaust valve is provided on the pipeline connecting the first drying tower and the exhaust device, a fourth exhaust valve is provided on the pipeline connecting the second drying tower and the exhaust device, and the third exhaust valve and the fourth exhaust valve are connected in parallel.

9. The carbon-nitrogen separation device for tail gas of BDO converter according to any one of claims 1 to 4, characterized in that: It also includes a second heat exchanger, which is located between the first fan and the dehydration device.

10. The carbon-nitrogen separation device for tail gas of BDO converter using acetylene-aldehyde process according to claim 8, characterized in that: The exhaust device is a muffler.

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