Device and method for reducing water content of condensate in flare of cracked gasoline hydrogenation unit

Abstract

The invention discloses a device and method for reducing the water content of the condensate in the flare of a pyrolysis gasoline hydrogenation device, and belongs to the technical field of pyrolysis gasoline hydrogenation. The device and method include: a deheptanizer; a decarbonization tower 9; a steam ejector, wherein the deheptanizer and the decarbonization tower 9 are respectively connected to the steam ejector through pipelines, and the condensate generated by the steam ejector is discharged to the flare system through the pipeline; a liquid ring vacuum pump system, which is respectively connected to the steam ejector and the decarbonization tower 9 through pipelines, and the gas extracted by the liquid ring vacuum pump system is discharged to the flare system through the pipeline, and the decarbonization tower 9 can be vacuumed through the liquid ring vacuum pump system or the steam ejector; the deheptanizer is only vacuumed through the steam ejector. By increasing the negative pressure required for the production of the decarbonization tower 9, the liquid ring vacuum pump system is provided, and no condensate is generated during the vacuuming process, thereby solving the problem of the high water content of the condensate in the flare for the pyrolysis gasoline hydrogenation device, once and for all, and can meet the production needs, and can also achieve the purpose of energy saving, consumption reduction and environmental protection.

Description

Technical Field

[0001] The invention belongs to the technical field of pyrolysis gasoline hydrogenation, and in particular relates to a device and a method for reducing the water content of flare condensate of a pyrolysis gasoline hydrogenation device. Background Art

[0002] Problems of existing pyrolysis gasoline hydrogenation units

[0003] In the existing pyrolysis gasoline hydrogenation unit, the tower pressure maintenance of the decarbonization tower 9 and the deheptane tower depends on the steam ejector to evacuate the tower to ensure the required negative pressure environment in the tower. However, this traditional method has the following problems:

[0004] The steam and non-condensable gases generated during the operation of the steam ejector form condensate after condensation. These condensates directly enter the hot flare discharge tank, causing the dirty oil in the flare tank to contain a large amount of water. Since the hot flare discharge tank itself is not designed with a special water cutting process, the water cannot be effectively separated. At the same time, the light dirty oil tank area cannot receive dirty oil containing a large amount of water. When the liquid level in the hot flare discharge tank is too high to be transported outside, the entire device will be forced to stop, affecting production continuity.

[0005] To solve this problem, the current measure is to regularly cut off the water through a temporary metal hose connected to the bottom of the flare condensate tank, and discharge the water in the water distribution bag to the oily wastewater system. However, since some hydrocarbons are easily brought out during the water cutting process, the concentration of surrounding combustible gas is high, and a large number of combustible gas alarms are triggered, which poses a major safety hazard. Summary of the invention

[0006] The present invention aims at the above problems existing in the prior art and proposes a device and a method for reducing the water content of the flare condensate of the cracking gasoline hydrogenation unit.

[0007] The present invention can be achieved through the following technical solutions:

[0008] A device for reducing the water content of condensate from a pyrolysis gasoline hydrogenation unit, comprising:

[0009] Deheptanizer;

[0010] Nine towers for decarbonization;

[0011] A steam ejector, wherein the deheptanizer tower and the nine-decarbonization tower are respectively connected to the steam ejector through pipelines, and the condensate generated by the steam ejector is discharged to the flare system through pipelines;

[0012] A liquid ring vacuum pump system is connected to the steam ejector and the nine decarbonization towers through pipelines, and the gas extracted by the liquid ring vacuum pump system is discharged to the flare system through pipelines, wherein:

[0013] The nine decarbonization towers can be evacuated by the liquid ring vacuum pump system or the steam ejector;

[0014] The deheptanizer is evacuated only by the steam ejector.

[0015] As a further improvement of the present invention, a first three-way pipe is provided on the pipeline connecting the deheptanizer, the decarbonization tower 9 and the steam ejector, a first shut-off valve is provided on the pipeline from the deheptanizer to the first three-way pipe, and a second shut-off valve is provided on the pipeline from the decarbonization tower 9 to the first three-way pipe;

[0016] A second tee is provided on the pipeline connecting the liquid ring vacuum pump system with the steam ejector and the nine-way decarbonization tower, and a third shut-off valve is provided on the pipeline from the liquid ring vacuum pump system to the second tee.

[0017] As a further improvement of the present invention, when the nine decarbonization tower is working and the deheptane tower is not working, the first cut-off valve and the second cut-off valve are closed, the third cut-off valve is opened, and the liquid ring vacuum pump system evacuates the nine decarbonization tower;

[0018] Or the first shut-off valve and the third shut-off valve are closed, the second shut-off valve is opened, and the steam ejector evacuates the decarbonization tower nine.

[0019] As a further improvement of the present invention, when the deheptanizer is working and the decarbonization tower 9 is not working, the first shut-off valve is opened, the second shut-off valve and the third shut-off valve are closed, and the steam ejector evacuates the deheptanizer.

[0020] As a further improvement of the present invention, when the decarbonization tower nine and the deheptanizer tower work simultaneously, the first cut-off valve is opened, the second cut-off valve is closed, the third cut-off valve is opened, the liquid ring vacuum pump system evacuates the decarbonization tower nine, and the steam ejector evacuates the deheptanizer tower.

[0021] As a further improvement of the present invention, the liquid ring vacuum pump system comprises a liquid ring vacuum pump, a gas-liquid separator and a heat exchanger, wherein the gas-liquid separator is connected to the outlet of the liquid ring vacuum pump, and the heat exchanger is connected to the gas-liquid separator and the liquid ring vacuum pump, wherein:

[0022] The liquid ring vacuum pump forms a vacuum after operation and extracts the gas in the decarbonization tower nine, the gas-liquid separator separates the gas from the liquid, the gas is discharged to the torch through a pipeline, the working fluid is sent to the heat exchanger for cooling and then sent back to the liquid ring vacuum pump.

[0023] As a further improvement of the present invention, a pressure regulating valve and an inlet buffer tank are provided on the pipeline from the second three-way pipe to the liquid ring vacuum pump, the gas-liquid separator is also connected to the inlet buffer tank through a pipeline, and a reflux regulating valve is provided on the pipeline between the gas-liquid separator and the inlet buffer tank.

[0024] As a further improvement of the present invention, the deheptanizer tower and the decarbonization tower 9 both have a tower top material extraction system, and the tower top material extraction system comprises:

[0025] A tower top cooler, a tower top reflux tank, and a tower top reflux pump, the tops of the nine decarbonization towers and the deheptane towers are individually connected to the tower top cooler, the tower top reflux tank, and the tower top reflux pump, wherein:

[0026] The top reflux tank is used to receive the liquid condensed by the top cooler. The top reflux tank has a first outlet and a second outlet. The first outlet is connected to the top of the decarbonization tower 9 or the deheptane tower through a top reflux pump and serves as a reflux path for the reflux liquid. The second outlet is used to be connected to the second-stage hydrogenation reactor and used as the product extraction. A second-stage hydrogenation feed pump is provided on the pipeline between the second outlet and the second-stage hydrogenation reactor.

[0027] As a further improvement of the present invention, the kettle of the decarbonization tower 9 and the deheptanizer tower also has a bottom material extraction system, and the kettle material extraction system includes a kettle reboiler, which is connected to the kettle of the decarbonization tower 9 or the deheptanizer tower, and the kettle reboiler collects the material produced at the bottom of the tower and sends it back to the kettle after heating, and at the same time, the unhydrogenated carbon eight product is discharged from the kettle.

[0028] A method for reducing the water content of condensate in a pyrolysis gasoline hydrogenation device, which is used to perform multi-condition treatment on the above-mentioned equipment capable of reducing the water content of condensate in a pyrolysis gasoline hydrogenation device, comprising:

[0029] Working condition 1: When the nine-tower decarbonization system works alone, the liquid ring vacuum pump evacuates the system and the steam emitter is in a closed state;

[0030] Working condition 2: when the nine-tower decarbonization system works alone, the steam emitter evacuates the system and the liquid ring vacuum pump is in a closed state;

[0031] Working condition three: when the deheptanizer system works alone, the steam emitter evacuates the deheptanizer system and the liquid ring vacuum pump is in a closed state;

[0032] Working condition 4: when the nine-tower decarbonization system and the deheptanization tower system are working simultaneously, the liquid ring vacuum pump evacuates the nine-tower decarbonization system, and at the same time, the steam emitter evacuates the deheptanization tower system.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. By adding a liquid ring vacuum pump system, when the nine decarbonization towers work alone, the liquid ring vacuum pump system can be used to replace the steam ejector for vacuum treatment, so that the steam ejector will no longer produce condensate to enter the flare system, and the waste oil in the hot flare discharge tank can be normally sent to the light waste oil tank, solving the problem of forced shutdown due to the light waste oil tank being unable to accept a large amount of condensate waste oil and causing the flare discharge tank to be too high to be sent out;

[0035] 2. There is no need to cut off the water of the hot flare oil tank regularly, which solves the potential safety hazard of some hydrocarbons being carried out during the original water cutting process, resulting in an increase in the concentration of surrounding combustible gas;

[0036] 3. The liquid ring vacuum pump system and the steam ejector serve as backup for each other. Therefore, when the liquid ring vacuum pump system fails, the steam ejector can still be used to evacuate the nine decarbonization towers to ensure the stability and continuity of production conditions.

[0037] 4. The multi-condition processing method not only improves the flexibility and stability of the system, but also brings significant economic and environmental benefits. It is suitable for the efficient operation of large-scale pyrolysis gasoline hydrogenation units. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The invention discloses a flow chart of an apparatus for reducing the water content of the condensate in the flare of a cracking gasoline hydrogenation unit.

[0039] In the figure, 100, decarbonization tower nine; 110, deheptanization tower; 120, tower top cooler; 130, tower top reflux tank; 140, tower top reflux pump; 150, tower bottom reboiler; 200, steam ejector; 300, liquid ring vacuum pump; 310, gas-liquid separator; 320, heat exchanger; 330, seal flushing pump; 340, pressure regulating valve; 350, inlet buffer tank; 360, reflux regulating valve; 400, first three-way pipe; 410, first shut-off valve; 420, second shut-off valve; 430, second three-way pipe; 440, third shut-off valve. DETAILED DESCRIPTION

[0040] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical method of the present invention, but the present invention is not limited to these embodiments.

[0041] like Figure 1 As shown, the present invention provides a device for reducing the water content of the condensate of the pyrolysis gasoline hydrogenation unit flare, comprising:

[0042] Decarbonization nine towers 100;

[0043] Deheptanizer 110;

[0044] The steam ejector 200, the deheptanizer 110 and the decarbonization tower 9 100 are respectively connected to the steam ejector 200 through pipelines, and the condensate generated by the steam ejector 200 is discharged to the flare system through the pipeline;

[0045] The liquid ring vacuum pump system is connected to the steam ejector 200 and the decarbonization tower 100 through pipelines. The gas extracted by the liquid ring vacuum pump system is discharged to the flare system through pipelines.

[0046] The decarbonization tower 9 100 can be evacuated by a liquid ring vacuum pump system or a steam ejector 200;

[0047] The deheptanizer 110 is evacuated only by the steam ejector 200 .

[0048] It is worth mentioning that a liquid ring vacuum pump system is additionally provided in the present embodiment. When the decarbonization tower 9 100 works alone, the liquid ring vacuum pump system can be used to replace the steam ejector 200 for vacuuming the tower, thereby making it possible for the steam ejector 200 to no longer produce condensate entering the flare system, and the waste oil in the hot flare discharge tank can be normally delivered to the light waste oil tank, thus solving the problem that the flare discharge tank is forced to stop because the light waste oil tank cannot accept the waste oil containing a large amount of condensate and the liquid level is too high to be delivered.

[0049] There is also no need to cut off the water from the hot flare oil tank regularly, which solves the potential safety hazard that some hydrocarbons are carried out during the original water cutting process, leading to an increase in the concentration of surrounding combustible gas.

[0050] Since the liquid ring vacuum pump system and the steam ejector 200 serve as backup for each other, when the liquid ring vacuum pump system fails, the steam ejector 200 can still be used to evacuate the decarbonization tower 9 100 to ensure the stability and continuity of the production conditions.

[0051] Since the deheptanizer 110 does not need to be used under normal production conditions, the steam ejector 200 is used for vacuuming the deheptanizer 110 to save costs.

[0052] That is to say, under normal production conditions, the decarbonization tower 9 100 works alone, and at this time, it is only necessary to start the liquid ring vacuum pump system. Once the liquid ring vacuum pump system fails, it is replaced by the steam ejector 200. Under some production conditions, if the decarbonization tower 9 100 and the deheptanizer 110 need to work at the same time, the liquid ring vacuum pump system evacuates the decarbonization tower 9 100, and the steam ejector 200 is used to evacuate the deheptanizer 110. By optimizing resource allocation, the utilization rate of equipment is improved, the cost is reduced, and the production conditions are made more flexible.

[0053] In order to more accurately control the vacuuming process of the deheptanizer 110 and the decarbonization tower 9 100, the present invention further optimizes the pipeline connection structure and clarifies the operation logic of the valve. The following are the specific configurations and operation steps:

[0054] 1. Pipeline and valve configuration

[0055] (1) First three-way pipe 400:

[0056] Connected to the pipeline between the deheptanizer 110, the decarbonization tower 9 100 and the steam ejector 200;

[0057] A first shut-off valve 410 is provided on the pipeline from the deheptanizer 110 to the first tee pipe 400;

[0058] A second shut-off valve 420 is provided on the pipeline from the ninth decarbonization tower 100 to the first three-way pipe 400 .

[0059] (2) Second three-way pipe 430:

[0060] Connected to the pipeline between the liquid ring vacuum pump system and the steam ejector 200 and the decarbonization tower 9 100;

[0061] A third shut-off valve 440 is provided on the pipeline from the liquid ring vacuum pump system to the second three-way pipe 430 .

[0062] 2. Operation mode and valve status

[0063] (1) The decarbonization tower 100 works alone, and the deheptane tower 110 does not work:

[0064] First shut-off valve 410: closed

[0065] Second shut-off valve 420: closed

[0066] Third cut-off valve 440: open

[0067] Operation: The liquid ring vacuum pump system evacuates the decarbonization tower 9 100 to prevent condensate from entering the flare system.

[0068] (2) The decarbonization tower 100 works alone, using a steam ejector 200:

[0069] First shut-off valve 410: closed

[0070] Second shut-off valve 420: open

[0071] Third cut-off valve 440: closed

[0072] Operation: The steam ejector 200 performs vacuum treatment on the decarbonization tower 9 100 as a backup plan.

[0073] (3) The deheptanizer 110 works alone, and the decarbonization tower 100 does not work:

[0074] First shut-off valve 410: open

[0075] Second shut-off valve 420: closed

[0076] Third cut-off valve 440: closed

[0077] Operation: The steam ejector 200 evacuates the deheptanizer 110.

[0078] (4) The decarbonization tower 9 100 and the deheptane tower 110 work simultaneously:

[0079] First shut-off valve 410: open

[0080] Second shut-off valve 420: closed

[0081] Third cut-off valve 440: open

[0082] Operation: The liquid ring vacuum pump system evacuates the decarbonization tower 9 100, and the steam ejector 200 evacuates the deheptane tower 110 to ensure that both towers can operate stably.

[0083] Through the above optimized design, the following significant advantages are achieved:

[0084] 1. Flexible switching: Through reasonable valve configuration, you can flexibly choose to use the liquid ring vacuum pump system or steam ejector 200 for vacuuming according to different working conditions, which improves the adaptability and flexibility of the system.

[0085] 2. Safe and reliable: The precise control of the valve ensures the safe operation of the equipment under different conditions. In particular, when the liquid ring vacuum pump system fails, it can quickly switch to the steam ejector 200 to ensure the continuity of production.

[0086] 3. Reduce potential safety hazards: When only the decarbonization tower 9 100 is working, the liquid ring vacuum pump system is preferably used to reduce the potential safety hazards caused by the condensate produced by the steam ejector 200 and avoid the risk of hydrocarbons being brought out during regular water cutting.

[0087] 4. Improve efficiency: Rationally distribute the workload of the liquid ring vacuum pump system and the steam ejector 200 so that both can perform at their best and improve overall production efficiency.

[0088] 5. Cost saving: Under normal production conditions, the existing steam ejector 200 is used to evacuate the deheptanizer 110, without the need for additional investment in new equipment, thereby reducing operating costs.

[0089] In summary, this optimized piping and valve configuration not only improves the stability and safety of the system, but also brings significant economic and environmental benefits, and is suitable for the efficient operation of large-scale pyrolysis gasoline hydrogenation units.

[0090] Preferably, the liquid ring vacuum pump system includes a liquid ring vacuum pump 300, a gas-liquid separator 310 and a heat exchanger 320, the gas-liquid separator 310 is connected to the outlet of the liquid ring vacuum pump 300, the heat exchanger 320 is connected to the gas-liquid separator 310 and the liquid ring vacuum pump 300, and the liquid separated by the gas-liquid separator 310 is transported to the heat exchanger 320 through a sealing flushing pump 330, wherein:

[0091] After the liquid ring vacuum pump 300 is put into operation, a vacuum is formed and the gas in the decarbonization tower 9 100 is extracted. The gas-liquid separator 310 separates the gas from the liquid. The gas is discharged to the torch through a pipeline. The working fluid is sent to the heat exchanger 320 for cooling and then sent back to the liquid ring vacuum pump 300 for recycling, thereby ensuring the continuous and stable operation of the liquid ring vacuum pump 300.

[0092] Furthermore, a pressure regulating valve 340 and an inlet buffer tank 350 are provided on the pipeline from the second three-way pipe 430 to the liquid ring vacuum pump 300, the gas-liquid separator 310 is also connected to the inlet buffer tank 350 through a pipeline, and a reflux regulating valve 360 ​​is provided on the pipeline between the gas-liquid separator 310 and the inlet buffer tank 350, wherein:

[0093] The pressure regulating valve 340 adjusts the pressure entering the liquid ring vacuum pump 300 as required to ensure that it operates under optimal working conditions;

[0094] The inlet buffer tank 350 receives the liquid from the decarbonization nine-tower 100 system and the reflux liquid from the gas-liquid separator 310, and provides stable feeding conditions, reduces the impact of air flow fluctuations on the liquid ring vacuum pump 300, and improves the stability of the system;

[0095] The reflux regulating valve 360 ​​is used to control the liquid in the gas-liquid separator 310 to reflux to the inlet buffer tank 350, maintain the liquid level balance and operation stability of the system, and prevent excessive liquid from directly entering the liquid ring vacuum pump 300 to cause overload or reduced efficiency.

[0096] Preferably, both the deheptanizer 110 and the decarbonization tower 100 have a tower top material extraction system, and the tower top material extraction system includes:

[0097] The top cooler 120, the top reflux tank 130, and the top reflux pump 140, the tops of the decarbonization tower 100 and the deheptane tower 110 are individually connected to the top cooler 120, the top reflux tank 130, and the top reflux pump 140, wherein:

[0098] The top reflux tank 130 is used to receive the liquid condensed by the top cooler 120. The top reflux tank 130 has a first outlet and a second outlet. The first outlet is connected to the top of the decarbonization tower 9 100 or the deheptane tower 110 through the top reflux pump 140 and serves as a reflux path for the reflux liquid. The second outlet is used to be connected to the second-stage hydrogenation reactor and used as the product extraction. A second-stage hydrogenation feed pump is provided on the pipeline between the second outlet and the second-stage hydrogenation reactor.

[0099] Preferably, the bottom of the decarbonization tower 9 100 and the deheptanizer 110 also has a bottom material extraction system, and the bottom material extraction system includes a bottom reboiler 150, which is connected to the bottom of the decarbonization tower 9 100 or the deheptanizer 110. The bottom reboiler 150 collects the material produced at the bottom of the tower and sends it back to the bottom after heating. At the same time, the unhydrogenated carbon eight product is discharged from the bottom of the tower.

[0100] The present invention also provides a method for reducing the water content of the condensate of the flare of the pyrolysis gasoline hydrogenation device, which is used for performing multi-condition treatment on the above-mentioned equipment capable of reducing the water content of the condensate of the flare of the large-scale pyrolysis gasoline hydrogenation device, comprising:

[0101] 1. Working condition 1: The decarbonization tower 100 works alone, and the liquid ring vacuum pump 300 is used for vacuuming. Applicable scenario: when only the decarbonization tower 100 needs to be distilled and separated.

[0102] Steps:

[0103] S1. Close the steam ejector 200 and its related valves (first shut-off valve 410, second shut-off valve 420);

[0104] S2, opening the third shut-off valve 440 of the liquid ring vacuum pump system;

[0105] S3. Start the liquid ring vacuum pump 300 to evacuate the decarbonization tower 100 so that no condensate enters the flare system.

[0106] Ensure the normal operation of auxiliary equipment such as the gas-liquid separator 310, the heat exchanger 320 and the inlet buffer tank 350 to maintain the stability of the liquid ring vacuum pump system.

[0107] 2. Working condition 2: The nine decarbonization towers 100 work alone, and the steam ejector 200 is used for vacuuming. Applicable scenarios: as a backup plan or when the liquid ring vacuum pump system fails.

[0108] Steps:

[0109] S1. Close the third shut-off valve 440 of the liquid ring vacuum pump system.

[0110] S2. Open the relevant valve (the second shut-off valve 420) of the steam ejector 200, and start the steam ejector 200 to perform vacuum treatment on the decarbonization tower 9 100.

[0111] S3. Monitor the liquid level of the flare discharge tank and take temporary water cut-off measures when necessary to avoid excessive liquid level affecting production.

[0112] 3. Working condition three: the deheptanizer 110 works alone and the steam ejector 200 is vacuumed. Applicable scenario: when only the deheptanizer 110 needs to be distilled and separated.

[0113] Steps:

[0114] S1. Open the relevant valve (the first shut-off valve 410) of the steam ejector 200, and close the other relevant valves (the second shut-off valve 420, the third shut-off valve 440).

[0115] S2. Start the steam ejector 200 to evacuate the deheptanizer 110.

[0116] 4. Working condition 4: Decarbonization tower 9 100 and deheptane tower 110 work simultaneously

[0117] Applicable scenario: When the decarbonization tower 9 100 and the deheptane tower 110 need to be distilled and separated at the same time.

[0118] Steps:

[0119] S1. Open the first shut-off valve 410V1 of the steam ejector 200, and close the second shut-off valve 420V2.

[0120] S2. Open the third shut-off valve 440V3 of the liquid ring vacuum pump system.

[0121] S3, start the liquid ring vacuum pump 300 to evacuate the decarbonization tower 9 100, and simultaneously start the steam ejector 200 to evacuate the deheptane tower 110.

[0122] This multi-condition processing method not only improves the flexibility and stability of the system, but also solves the problem of forced shutdown due to the flare discharge tank liquid level being too high to be transported outside because the light oil tank cannot accept the large amount of condensate oil, as well as the safety hazard caused by the carryout of some hydrocarbons in the original water cutting process, resulting in an increase in the concentration of surrounding combustible gas. It also brings significant economic and environmental benefits and is suitable for the efficient operation of large-scale pyrolysis gasoline hydrogenation units.

[0123] It should be noted that in actual application, when the decarbonization tower 9 100 is started for the first time to draw negative pressure, it is necessary to first use a steam jet pump 200 to draw vacuum inside the tower, and then use a liquid ring vacuum pump 300 to draw vacuum inside the tower after the vacuum degree drops;

[0124] This is because the liquid ring vacuum pump 300 is designed according to the exhaust gas composition during normal production, and the composition is relatively light. When it is first started, there is a lot of nitrogen in the tower and the composition is heavy. The liquid ring vacuum pump 300 cannot provide sufficient negative pressure extraction capacity, so it needs to be used in conjunction with the steam jet pump 200.

[0125] The technical means disclosed in the scheme of the present invention are not limited to the technical means disclosed in the above technical means, but also include technical schemes composed of any combination of the above technical features. The above is a specific implementation of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also regarded as the protection scope of the present invention.

[0126] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0127] In addition, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0128] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0129] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A device for reducing the water content of condensate from the pyrolysis gasoline hydrogenation unit, characterized in that: include: Deheptanizer; Nine towers for decarbonization; A steam ejector, wherein the deheptanizer tower and the nine-decarbonization tower are respectively connected to the steam ejector through pipelines, and the condensate generated by the steam ejector is discharged to the flare system through pipelines; A liquid ring vacuum pump system is connected to the steam ejector and the nine decarbonization towers through pipelines, and the gas extracted by the liquid ring vacuum pump system is discharged to the flare system through pipelines, wherein: The nine decarbonization towers can be evacuated by the liquid ring vacuum pump system or the steam ejector; The deheptanizer is evacuated only by the steam ejector.

2. The device for reducing the water content of condensate in the flare of a pyrolysis gasoline hydrogenation unit according to claim 1, characterized in that: A first tee is provided on the pipeline connecting the deheptanizer, the decarbonization tower 9 and the steam ejector, a first shut-off valve is provided on the pipeline from the deheptanizer to the first tee, and a second shut-off valve is provided on the pipeline from the decarbonization tower 9 to the first tee; A second tee is provided on the pipeline connecting the liquid ring vacuum pump system with the steam ejector and the nine-way decarbonization tower, and a third shut-off valve is provided on the pipeline from the liquid ring vacuum pump system to the second tee.

3. The device for reducing the water content of condensate in the flare of a pyrolysis gasoline hydrogenation unit according to claim 2, characterized in that: When the nine decarbonization towers are in operation and the deheptane tower is not in operation, the first cut-off valve and the second cut-off valve are closed, the third cut-off valve is opened, and the liquid ring vacuum pump system evacuates the nine decarbonization towers; Or the first shut-off valve and the third shut-off valve are closed, the second shut-off valve is opened, and the steam ejector evacuates the decarbonization tower nine.

4. The device for reducing the water content of the condensate of the pyrolysis gasoline hydrogenation unit according to claim 2, characterized in that: When the deheptanizer is in operation and the decarbonization tower 9 is not in operation, the first shut-off valve is opened, the second shut-off valve and the third shut-off valve are closed, and the steam ejector evacuates the deheptanizer.

5. The device for reducing the water content of the condensate of the pyrolysis gasoline hydrogenation unit according to claim 2, characterized in that: When the decarbonization tower nine and the deheptanizer tower are operating simultaneously, the first shut-off valve is opened, the second shut-off valve is closed, the third shut-off valve is opened, the liquid ring vacuum pump system evacuates the decarbonization tower nine, and the steam ejector evacuates the deheptanizer tower.

6. The device for reducing the water content of the condensate of the pyrolysis gasoline hydrogenation unit according to claim 2, characterized in that: The liquid ring vacuum pump system comprises a liquid ring vacuum pump, a gas-liquid separator and a heat exchanger, wherein the gas-liquid separator is connected to the outlet of the liquid ring vacuum pump, and the heat exchanger is connected to the gas-liquid separator and the liquid ring vacuum pump, wherein: The liquid ring vacuum pump forms a vacuum after operation and extracts the gas in the decarbonization tower nine, the gas-liquid separator separates the gas from the liquid, the gas is discharged to the torch through a pipeline, the working fluid is sent to the heat exchanger for cooling and then sent back to the liquid ring vacuum pump.

7. The device for reducing the water content of the condensate of the pyrolysis gasoline hydrogenation unit according to claim 6, characterized in that: A pressure regulating valve and an inlet buffer tank are provided on the pipeline from the second three-way pipe to the liquid ring vacuum pump, the gas-liquid separator is also connected to the inlet buffer tank through a pipeline, and a reflux regulating valve is provided on the pipeline between the gas-liquid separator and the inlet buffer tank.

8. The device for reducing the water content of condensate in the flare of a pyrolysis gasoline hydrogenation unit according to claim 1, characterized in that: The deheptanizer tower and the nine-decarbonization tower both have a tower top material extraction system, and the tower top material extraction system includes: A tower top cooler, a tower top reflux tank, and a tower top reflux pump, the tops of the nine decarbonization towers and the deheptane towers are individually connected to the tower top cooler, the tower top reflux tank, and the tower top reflux pump, wherein: The top reflux tank is used to receive the liquid condensed by the top cooler. The top reflux tank has a first outlet and a second outlet. The first outlet is connected to the top of the decarbonization tower 9 or the deheptane tower through a top reflux pump and serves as a reflux path for the reflux liquid. The second outlet is used to be connected to the second-stage hydrogenation reactor and used as the product extraction. A second-stage hydrogenation feed pump is provided on the pipeline between the second outlet and the second-stage hydrogenation reactor.

9. The device for reducing the water content of condensate in the flare of a pyrolysis gasoline hydrogenation unit according to claim 1, characterized in that: The kettle of the decarbonization tower 9 and the deheptane tower also has a bottom material extraction system, and the kettle material extraction system includes a kettle reboiler, which is connected to the kettle of the decarbonization tower 9 or the deheptane tower. The kettle reboiler collects the material produced at the bottom of the tower and sends it back to the kettle after heating, and at the same time, the unhydrogenated carbon eight product is discharged from the kettle.

10. A method for reducing the water content of condensate from a pyrolysis gasoline hydrogenation unit, for performing multi-condition treatment on the device capable of reducing the water content of condensate from a pyrolysis gasoline hydrogenation unit according to any one of claims 1 to 9, characterized in that: include: Working condition 1: When the nine-tower decarbonization system works alone, the liquid ring vacuum pump evacuates the system and the steam emitter is in a closed state; Working condition 2: when the nine-tower decarbonization system works alone, the steam emitter evacuates the system and the liquid ring vacuum pump is in a closed state; Working condition three: when the deheptanizer system works alone, the steam emitter evacuates the deheptanizer system and the liquid ring vacuum pump is in a closed state; Working condition 4: when the nine-tower decarbonization system and the deheptanization tower system are working simultaneously, the liquid ring vacuum pump evacuates the nine-tower decarbonization system, and at the same time, the steam emitter evacuates the deheptanization tower system.

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