Control system for gas phase recovery in styrene process

Abstract

The present invention discloses a styrene process gas phase recovery control system, and belongs to the technical field of chemical industry production, a quench tower is provided with a gas phase inlet, a gas phase outlet and a liquid discharge port, the gas phase outlet is connected with an inlet of a filtration demisting system through a pipeline, and an outlet of the filtration demisting system is connected with an inlet of a tail gas compressor through a pipeline; a lean oil outlet of the oil separator is connected with an inlet of the absorbent circulating pump through a pipeline, an outlet of the absorbent circulating pump is connected with an inlet of the cascade heat exchange module through a pipeline, and an outlet of the cascade heat exchange module is connected with an inlet of the distributor through a pipeline to form an absorbent circulating loop. The problems that the recovery rate of styrene is only maintained at 90-92% due to the defects of limited gas-liquid contact area, insufficient mass transfer efficiency and the like caused by the adoption of single solvent spraying absorption in the traditional quenching gas phase absorption technology, and the adaptability to operation parameter fluctuation is poor and the cost is low in the prior art are solved. The pressure difference of the absorption tower is easy to increase and the heat exchange efficiency is easy to decrease when raw material components are changed or the load is adjusted.

Description

Technical Field

[0001] This invention belongs to the field of chemical production technology, specifically relating to a control system for gas phase recovery in a styrene process. Background Technology

[0002] In various chemical industrial production processes, the quench system is a key process for the absorption of gaseous components, and its stable operation is crucial. The main rotating equipment for treating the tail gas in styrene plants is the screw compressor, which uses an 816 rotor. Due to the large volume of tail gas and the large rotor diameter, styrene is highly prone to polymerization, making it difficult to control the temperature excessively high. The current tail gas treatment method involves direct compression and end-of-pipe treatment. This method suffers from low resource recovery rates; useful components such as hydrocarbons, non-condensable gases, and heat energy in the tail gas are not effectively recovered and directly enter the compression and subsequent treatment stages, causing serious polymerization problems. On the one hand, the compression system operates under high load, but the reaction system load remains high, affecting the reaction pressure of the dehydrogenation system. Catalyst dust, tar, and styrene entrained in the exhaust gas can easily cause compressor wear, carbon ring seal failure, and blockage, increasing equipment maintenance costs and downtime frequency, and shortening the unit's operating cycle. On the other hand, direct compression of untreated exhaust gas requires a large amount of steam, resulting in excessive turbine load. Currently, the single unit's usage is over 15t / h, and the steam quality requirements are high, leading to increased machine vibration and increased difficulty in end-of-pipe treatment. This increases the risk of pollutant emissions exceeding standards, which does not comply with the "dual-carbon" strategy and green manufacturing requirements.

[0003] At different stages, the equipment exhibits different states. Stress reactions on the equipment body often lead to uneven dynamic balance vibrations. During operation, the exhaust gas compressor inlet pipeline experiences increased vibration due to factors such as inlet gas flow, temperature changes, and its own vibration. If these variables are not effectively regulated, they may cause overpressure deformation, leaks, or even safety valve activation and reactor system overpressure, affecting the selectivity of the reaction zone and potentially leading to equipment safety accidents. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a control system for gas phase recovery in styrene processes, in order to solve the problems of traditional quench gas phase absorption technology, which mostly uses single solvent spray absorption, resulting in limited gas-liquid contact area and insufficient mass transfer efficiency, leading to a styrene recovery rate of only 90%-92%. In addition, the existing technology has poor adaptability to fluctuations in operating parameters, and is prone to increasing pressure difference in the absorption tower and decreasing heat exchange efficiency when the raw material composition changes or the load is adjusted.

[0005] The above-mentioned technical objective of this invention is achieved through the following technical solution: A control system for gas phase recovery in a styrene process, comprising a quench tower, a filtration and demisting system, a cascade heat exchange module, an absorbent circulation pump, and a regulating control module, characterized in that:

[0006] The quench tower is arranged from top to bottom as follows: a distributor, adsorbent material, collection system, oil separator and liquid storage tank. The lower middle part of the quench tower is provided with a gas phase inlet, the top is provided with a gas phase outlet and the bottom is provided with a liquid drain.

[0007] The gas phase outlet is connected to the inlet of the filtration and demisting system via a pipeline. The outlet of the filtration and demisting system is connected to the inlet of the exhaust gas compressor via a pipeline. The lean oil outlet of the oil separator is connected to the inlet of the absorbent circulation pump via a pipeline. The outlet of the absorbent circulation pump is connected to the inlet of the cascade heat exchange module via a pipeline. The outlet of the cascade heat exchange module is connected to the inlet of the distributor via a pipeline, forming a circulation loop for the absorbent.

[0008] The distributor and collection system are designed with angles to reduce the residence time of styrene during the downward penetration of the absorbent, thus preventing polymerization. The adsorbent material consists of four layers of packing material, which adopts a structure of staged spraying, cross-flow contact, and inclined discharge. The first and third layers of packing material are oriented in the same direction, while the second layer of packing material is received in the opposite direction to the spraying direction of the distributor and tilted at 45 degrees to the upper right. The adsorbent material in the third and fourth layers is arranged at 45-degree angles. The liquid receiving tray of the collection system adopts an adjustable tilt angle structure and is arranged at center line points.

[0009] The adjustment and control module adjusts the temperature control valve of the cascade heat exchange module and the frequency of the absorbent circulation pump according to the operating status of the exhaust gas compressor and the temperature and flow parameters of the absorbent, thereby controlling the balance of mass transfer in the quench gas phase absorption.

[0010] By adopting the above technical solution: the oil separator collects the material in the receiving pan through the collection system to separate rich oil and lean oil. The rich oil is centrally recovered into the storage tank and then enters the subsequent unit. The absorbent circulation pump sends the lean oil absorbent from the oil separator to the stepped heat exchange module for stepped heat exchange. The data from the online analysis module is fed back to the regulation and control module. The operating condition data such as the inlet pressure and frequency of the exhaust gas compressor are fed back to the gas-liquid temperature control module and transmitted to the exhaust gas compressor system, which in turn affects the feed rate of the absorbent liquid.

[0011] The regulating control module and the gas-liquid temperature control module adjust the temperature and flow control of the cascade heat exchange module according to the operating status of the exhaust gas compressor, thereby controlling the balance of mass transfer in the quenching gas phase absorption, and distributing the deviation caused by the adjustment of the tilt height of the circulating control liquid evenly in the gas phase medium through the distributor.

[0012] Furthermore, the distributor includes a throttling device and multiple spraying devices. The nozzles of the spraying devices are arranged downwards opposite to the adsorbent material below. The spraying devices can adjust the absorption liquid to be sprayed evenly on the upper surface of the adsorbent material, and staged spraying is achieved through staggered docking.

[0013] In the above technical solution: the distributor includes a throttling device and four spraying devices. The throttling device is used to prevent the absorption liquid from flowing too fast due to gravity caused by excessive tilt angle. The multiple spraying devices are used to adjust the spray angle so that the absorbent is sprayed evenly on the surface of the adsorbent material. Through staggered docking, graded spraying, cross-flow contact, and tilted discharge, the effective components in the gas phase are fully absorbed.

[0014] Furthermore, the second layer of the adsorbent material is arranged at a 90-degree angle to the spray direction of the distributor's spraying equipment, and the upper right corner of the second layer of the packing is tilted at a 45-degree angle relative to the horizontal direction.

[0015] By adopting the above technical solution: the adsorption material includes four layers of packing. The first and third layers of packing are in the same direction. The receiving direction of the second layer of packing is opposite to the direction of the spraying equipment of the distributor. The upper right corner of the second layer of packing is tilted at 45°. The adsorption materials of the third and fourth layers of packing are arranged at 45° intervals.

[0016] Furthermore, the liquid receiving plate of the collection system is located below the adsorbent material, and the tilt angle of the liquid receiving plate is adjustable to prevent the liquid from staying on the liquid receiving plate for too long, which could lead to polymerization.

[0017] Furthermore, it also includes an online analysis module and a gas-liquid temperature control module. The online analysis module is installed on the pipeline between the cascade heat exchange module and the distributor, and is used to analyze the flow rate and composition of the absorbent. The gas-liquid temperature control module is installed on the inlet pipeline of the exhaust gas compressor, and is used to monitor the temperature and pressure of the inlet gas phase. The regulation and control module includes a programmable logic controller (PLC) pressure control module. The signal input terminal of the PLC pressure control module is electrically connected to the signal output terminals of the online analysis module and the gas-liquid temperature control module, respectively. The control output terminal of the PLC pressure control module is electrically connected to the temperature control valve of the cascade heat exchange module, the frequency control terminal of the absorbent circulation pump, and the control terminal of the exhaust gas compressor system, respectively.

[0018] Furthermore, it also includes a polymerization inhibitor injection system, the injection end of which is connected to the front end pipeline of the gas phase inlet of the quench tower, for injecting polymerization inhibitor into the gas phase entering the quench tower to reduce the polymerization of the liquid in the storage tank.

[0019] Furthermore, the quench tower is also equipped with an evaporation structure, which is installed on the side wall of the liquid storage tank. The evaporation structure alleviates the problem of polymerization residue of the adsorbent material by using the effect of higher temperature of the gas phase medium.

[0020] Furthermore, the evaporation structure is a heating coil installed on the side wall of the storage tank, or a stripping steam distribution pipe extending inward from the lower side wall of the quench tower, used to heat and evaporate or strip the rich oil in the storage tank to remove light components and prevent polymerization.

[0021] Furthermore, the adjustment and control module links the monitored exhaust gas compressor inlet pressure frequency signal with the feedback signal of the online analysis module, and adjusts the flow rate of the absorbent circulation pump according to the operating status of the exhaust gas compressor, which in turn affects the feed rate of the absorbent liquid to maintain the pressure balance of the system.

[0022] Furthermore, a flow regulating valve is installed on the pipeline between the cascade heat exchange module and the distributor. The control terminal of the flow regulating valve is electrically connected to the control output terminal of the regulating control module, and is used to adjust the feed rate of the absorbent according to the feedback signal of the online analysis module.

[0023] Compared with the prior art, the present invention has the following advantages: by matching the angle of the distributor and the collection system and the 45° inclined cross-flow arrangement of the four layers of adsorbent packing, the absorbent flows rapidly along the inclined surface during downward penetration, which reduces the residence time of styrene compared with the traditional horizontal packed tower and effectively inhibits the growth of free radical polymerization chains. At the same time, the 90° cross-flow contact causes the liquid phase to change abruptly in each layer of packing, which accelerates the renewal of the liquid surface and avoids the formation of stagnant liquid film on the surface of traditional horizontal packing. Combined with the addition of polymerization inhibitor and evaporation structure, a dual chemical and physical anti-polymerization mechanism is formed, which controls the polymerization rate of adsorbent and liquid storage tank in the quench tower at an extremely low level.

[0024] The process employs a combination of staged spraying, cross-flow contact, and inclined discharge, with four layers of packing forming a multi-stage absorption: the first layer achieves preliminary absorption, the second layer improves mass transfer efficiency through 90-degree cross-flow shear, the third layer performs deep absorption, and the fourth layer further captures residual styrene. The 45-degree inclined arrangement ensures sufficient gas-liquid contact and intense turbulence, resulting in a styrene recovery rate of over 95%, reducing styrene raw material loss caused by incomplete absorption.

[0025] This invention integrates the distributor, adsorption material, collection system, oil separator, liquid storage tank, and evaporation structure sequentially from top to bottom into a single quench tower, forming an integrated structure for absorption, separation, and liquid storage. This eliminates dead zones in the flow of external pipeline connections, bends, valves, etc., reducing the equipment's footprint. At the same time, the internally integrated oil separator enables real-time gas-liquid separation, allowing lean oil to circulate directly and rich oil to be discharged promptly, avoiding the problem of decreased absorption efficiency caused by the mixed circulation of rich and lean oil. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of the present invention.

[0027] In the diagram: 1. Filtration and demisting system; 2. Regulation and control module; 3. Cascade heat exchange module; 4. Absorbent circulation pump; 6. Gas-liquid temperature control module; 7. Online analysis module; 9. Adsorbent material; 10. Distributor; 11. Oil separator; 12. Evaporation structure; 13. Liquid storage tank; 14. Polymerization inhibitor injection system; 15. Collection system; 16. Quenching tower. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate specific implementation methods of the present invention, but the protection scope of the present invention is not limited to the following embodiments. Where specific technical conditions are not specified in the embodiments, they are implemented according to conventional technical means in the art; where specific experimental data are not specified, they are executed according to conventional chemical production parameters.

[0029] Example 1:

[0030] A control system for gas phase recovery in a styrene process includes a quench tower 16, a filtration and demisting system 1, a cascade heat exchange module 3, an absorbent circulation pump 4, and a regulation and control module 2.

[0031] The quench tower 16 is arranged from top to bottom as follows: distributor 10, adsorbent material 9, collection system 15, oil separator 11 and liquid storage tank 13. The quench tower 16 is provided with a gas phase inlet in the middle and lower part, a gas phase outlet at the top and a liquid outlet at the bottom.

[0032] The gas phase outlet is connected to the inlet of the filter and demisting system 1 via a pipeline. The outlet of the filter and demisting system 1 is connected to the inlet of the exhaust gas compressor via a pipeline. The lean oil outlet of the oil separator 11 is connected to the inlet of the absorbent circulation pump 4 via a pipeline. The outlet of the absorbent circulation pump 4 is connected to the inlet of the stepped heat exchange module 3 via a pipeline. The outlet of the stepped heat exchange module 3 is connected to the inlet of the distributor 10 via a pipeline, forming a circulation loop for the absorbent.

[0033] The liquid receiving tray of the collection system 15 is located below the adsorbent material. The tilt angle of the liquid receiving tray is adjustable to prevent the liquid from staying on the liquid receiving tray for too long, which could lead to polymerization. The distributor 10 and the collection system 15 are designed with angles to reduce the residence time of styrene during the downward penetration of the absorbent, thus preventing polymerization. The distributor 10 includes a throttling device and multiple spraying devices. The nozzles of the spraying devices are set downwards and opposite to the adsorbent material 9 below. The spraying devices can be adjusted to spray the absorbent liquid evenly on the upper surface of the adsorbent material 9, and staged spraying is achieved through staggered docking.

[0034] The adsorbent material 9 comprises four layers of packing material, employing a structure of staged spraying, cross-flow contact, and inclined discharge. The first and third layers of packing material are oriented in the same direction. The second layer of packing material has a receiving direction opposite to the spraying direction of the distributor 10 and is tilted at a 45-degree angle to the upper right. The third and fourth layers of adsorbent material 9 are arranged at 45-degree intervals. The receiving tray of the collection system 15 employs an adjustable tilt angle structure and is arranged at center-line points. The second layer of packing material 9 is arranged at a 90-degree cross-flow angle to the spraying direction of the distributor 10, and the upper right corner of the second layer of packing material is tilted at a 45-degree angle relative to the horizontal direction.

[0035] The regulation and control module 2 adjusts the temperature control valve of the stage heat exchange module 3 and the frequency of the absorbent circulation pump according to the operating status of the exhaust gas compressor and the temperature and flow parameters of the absorbent, thereby controlling the balance of mass transfer in the quench gas phase absorption. The regulation and control module 2 links the monitored exhaust gas compressor inlet pressure frequency signal with the feedback signal of the online analysis module 7, and adjusts the flow rate of the absorbent circulation pump 4 according to the operating status of the exhaust gas compressor, which in turn affects the feed rate of the absorbent liquid to maintain the pressure balance of the system. A flow regulating valve is installed on the pipeline between the stage heat exchange module 3 and the distributor 10. The control terminal of the flow regulating valve is electrically connected to the control output terminal of the regulation and control module 2, and is used to adjust the feed rate of the absorbent according to the feedback signal of the online analysis module 7.

[0036] The online analysis module 7 is installed on the pipeline between the cascade heat exchange module 3 and the distributor 10, and is used to analyze the flow rate and composition of the absorbent. The gas-liquid temperature control module 6 is installed on the inlet pipeline of the exhaust gas compressor, and is used to monitor the temperature and pressure of the inlet gas phase. The regulation and control module 2 includes a programmable logic controller (PLC) pressure control module. The signal input terminal of the PLC pressure control module is electrically connected to the signal output terminals of the online analysis module 7 and the gas-liquid temperature control module 6, respectively. The control output terminal of the PLC pressure control module is electrically connected to the temperature control valve of the cascade heat exchange module 3, the frequency control terminal of the absorbent circulation pump 4, and the control terminal of the exhaust gas compressor system, respectively.

[0037] The injection end of the polymerization inhibitor injection system 14 is connected to the front end pipeline of the gas phase inlet of the quench tower 16, and is used to inject polymerization inhibitor into the gas phase entering the quench tower to reduce the polymerization of the liquid in the storage tank 13.

[0038] The quench tower 16 is also equipped with an evaporation structure 12, which is installed on the side wall of the liquid storage tank 13. The evaporation structure 12 alleviates the problem of polymerization residue of the adsorbent material by using the effect of higher temperature of the gas phase medium. The evaporation structure 12 is a heating coil installed on the side wall of the liquid storage tank, or a stripping steam distribution pipe extending inward from the lower side wall of the quench tower 16. It is used to heat and evaporate or strip the rich oil in the liquid storage tank 13 to remove light components and prevent polymerization.

[0039] In the above technical solution, the hydrogen-rich tail gas from the ethylbenzene dehydrogenation reaction system is first injected with a polymerization inhibitor at the front end of the gas phase inlet of the quench tower 16 through the polymerization inhibitor injection system 14, and then enters the space at the bottom of the quench tower 16 from the gas phase inlet in the middle and lower part of the quench tower 16. The gas phase flows from bottom to top in the quench tower 16 and passes through the four packing layers of adsorbent material 9 in sequence.

[0040] The spray angle of the distributor 10, combined with the inclined liquid receiving plate of the collection system 15, allows the absorbent to flow rapidly along the surface of the inclined packing as it penetrates the absorbent material 9 downwards, avoiding the formation of a stagnant liquid film on the surface of the traditional horizontal packing. The liquid receiving plate of the collection system 15 adopts an adjustable tilt angle structure of 15°-45° to ensure that the rich absorbent flows rapidly to the oil separator 11, avoiding the accumulation and polymerization of liquid in the bottom area of ​​the tower.

[0041] Within the packing layer, the gas phase and the absorbent sprayed from top to bottom by the distributor 10 undergo graded spraying and cross-flow contact. In the first packing layer, the gas phase and absorbent initially come into contact, and most of the styrene vapor is absorbed. The direction of the second packing layer is 90° opposite to the spraying direction of the distributor and inclined at 45°. The gas phase flow direction is forced to change, forming a transverse cross-flow shear with the absorbent, which improves the transfer efficiency. At the same time, the liquid flows down quickly on the inclined surface, reducing the residence time. The direction of the third packing layer is consistent with the first packing layer. The gas phase adjusts its flow direction again here for deep absorption. The fourth packing layer is arranged at 45° intervals to further capture residual styrene. The upper right corner of the second packing layer of the adsorbent material 9 is inclined at 45°, forming a directional difference with the first and third layers. This causes a sudden change in the flow direction of the liquid phase between each packing layer, accelerates the renewal of the liquid surface, and significantly shortens the residence time of styrene molecules on the packing surface, thereby inhibiting the chain growth process of the free radical polymerization reaction. The purified gas phase is discharged from the top gas phase outlet of the quench tower 16, enters the filtration and demisting system 1 through the pipeline to remove entrained droplets and toxic substances, and then enters the tail gas compressor inlet pipeline.

[0042] After being collected by the collection system 15, the rich absorbent directly enters the oil separator 11 located at the bottom of the tower. Utilizing the principle of gravity settling, the denser rich oil settles into the storage tank 13, while the less dense lean oil absorbent is connected to the absorbent circulation pump 4 from the side wall circulating liquid outlet pipeline.

[0043] The cascade heat exchange module 3 cools the circulating absorbent to 35 to 45 degrees Celsius and then sends it into the distributor 10 to maintain the temperature of the absorption section in the quench tower 16 below the critical temperature for styrene polymerization. At the same time, the evaporation structure 12 heats the rich oil in the storage tank 13, and reduces the viscosity of the rich oil by moderately raising the temperature, promoting the volatilization of light components and preventing polymerization caused by low temperature and high viscosity during the storage stage.

[0044] The online analysis module 7 monitors the absorbent flow rate and composition in real time, while the gas-liquid temperature control module 6 monitors the inlet pressure and temperature of the exhaust gas compressor. The programmable logic controller pressure control module of the regulation and control module 2 receives these signals and calculates the optimal absorbent circulation rate and temperature using a preset algorithm.

[0045] When the inlet pressure of the exhaust gas compressor increases due to the increase in gas phase load, the regulating control module 2 adjusts the frequency of the absorbent circulation pump 4 and the temperature control valve of the stage heat exchange module 3 in conjunction to enhance the absorption effect, reduce the partial pressure of styrene in the gas phase, and thus stabilize the compressor inlet pressure within the process range.

[0046] The flow regulating valve between the cascade heat exchange module 3 and the distributor 10 is fine-tuned based on the feedback signal from the online analysis module 7 to ensure that the absorbent feed rate matches the gas phase load. This avoids excessive spraying leading to liquid accumulation in the tower or insufficient spraying causing a decrease in absorption efficiency. Through the linkage of the adjustment control module 2 with the online analysis module 7 and the gas-liquid temperature control module 6, feedforward and feedback composite control is achieved: the online analysis module 7 monitors the absorbent flow rate and composition in real time, the gas-liquid temperature control module 6 monitors the inlet pressure and temperature of the tail gas compressor, and the PLC automatically adjusts the frequency of the absorbent circulation pump 4 and the temperature of the cascade heat exchange module 3 according to a preset algorithm. When the compressor inlet pressure fluctuates, the system can quickly adjust the absorbent circulation rate and temperature within ±5% to stabilize the pressure within the process control range. This effectively avoids compressor vibration, safety valve activation, and overpressure problems in the reaction system caused by pressure fluctuations in existing technologies, significantly reducing equipment failure rate and maintenance costs.

[0047] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A control system for gas phase recovery in a styrene process, comprising a quench tower (16), a filtration and demisting system (1), a cascade heat exchange module (3), an absorbent circulation pump (4), and a regulating control module (2), characterized in that: The quench tower (16) is arranged from top to bottom as follows: distributor (10), adsorbent material (9), collection system (15), oil separator (11) and liquid storage tank (13). The quench tower (16) is provided with a gas phase inlet in the middle and lower part, a gas phase outlet at the top, and a liquid drain at the bottom. The gas phase outlet is connected to the inlet of the filter and demisting system (1) through a pipeline. The outlet of the filter and demisting system (1) is connected to the inlet of the exhaust gas compressor through a pipeline. The lean oil outlet of the oil separator (11) is connected to the inlet of the absorbent circulation pump (4) through a pipeline. The outlet of the absorbent circulation pump (4) is connected to the inlet of the cascade heat exchange module (3) through a pipeline. The outlet of the cascade heat exchange module (3) is connected to the inlet of the distributor (10) through a pipeline, forming a circulation loop for the absorbent. The distributor (10) and the collection system (15) are designed with angles to reduce the residence time of styrene during the downward penetration of the absorbent, thus preventing polymerization. The adsorbent material (9) consists of four layers of packing material, which adopts a structure of graded spraying, cross-flow contact, and inclined discharge. The packing direction of the first and third layers is the same, the receiving direction of the packing material of the second layer is opposite to the spraying direction of the distributor (10) and tilted at 45 degrees to the upper right. The adsorbent material (9) of the third and fourth layers is arranged at 45-degree angles. The liquid receiving tray of the collection system (15) adopts a structure with adjustable tilt angle and is arranged at center line points. The regulating control module (2) adjusts the temperature control valve of the stepped heat exchange module (3) and the frequency of the absorbent circulation pump according to the operating status of the exhaust gas compressor and the temperature and flow parameters of the absorbent, thereby controlling the balance of mass transfer in the quench gas phase absorption.

2. The control system for gas phase recovery in a styrene process according to claim 1, characterized in that, The distributor (10) includes a throttling device and multiple spraying devices. The nozzles of the spraying devices are set downwards and opposite to the adsorbent material (9) below. The spraying devices can adjust the absorption liquid to be sprayed evenly on the upper surface of the adsorbent material (9) and achieve graded spraying through staggered docking.

3. The control system for gas phase recovery in a styrene process according to claim 2, characterized in that, The second layer of the adsorbent material (9) is arranged at a 90-degree angle to the spray direction of the spraying device of the distributor (10), and the upper right corner of the second layer of the adsorbent material is tilted at a 45-degree angle relative to the horizontal direction.

4. The control system for gas phase recovery in a styrene process according to claim 1, characterized in that, The liquid receiving plate of the collection system (15) is located below the adsorbent material. The tilt angle of the liquid receiving plate is adjustable to prevent the liquid from staying on the liquid receiving plate for too long, which could lead to polymerization.

5. The control system for gas phase recovery in a styrene process according to claim 1, characterized in that, It also includes an online analysis module (7) and a gas-liquid temperature control module (6). The online analysis module (7) is located on the pipeline between the cascade heat exchange module (3) and the distributor (10) and is used to analyze the flow rate and composition of the absorbent. The gas-liquid temperature control module (6) is located on the inlet pipeline of the tail gas compressor and is used to monitor the temperature and pressure of the inlet gas phase. The regulation and control module (2) includes a programmable logic controller (PLC) pressure control module. The signal input terminal of the PLC pressure control module is electrically connected to the signal output terminals of the online analysis module (7) and the gas-liquid temperature control module (6), respectively. The control output terminal of the PLC pressure control module is electrically connected to the temperature control valve of the cascade heat exchange module (3), the frequency control terminal of the absorbent circulation pump (4), and the control terminal of the tail gas compressor system, respectively.

6. The control system for gas phase recovery in a styrene process according to claim 1, characterized in that, It also includes a polymerization inhibitor injection system (14), the injection end of which is connected to the front end pipeline of the gas phase inlet of the quench tower (16) for injecting polymerization inhibitor into the gas phase entering the quench tower to reduce the polymerization of liquid in the storage tank (13).

7. The control system for gas phase recovery in a styrene process according to claim 1, characterized in that, The quench tower (16) is also equipped with an evaporation structure (12), which is installed on the side wall of the liquid storage tank (13). The evaporation structure (12) alleviates the problem of polymer residue of the adsorbent material by the effect of the higher temperature of the gas phase medium.

8. A control system for gas phase recovery in a styrene process according to claim 7, characterized in that, The evaporation structure (12) is a heating coil installed on the side wall of the storage tank, or a stripping steam distribution pipe extending inward from the lower side wall of the quench tower (16), used to heat and evaporate or strip the rich oil in the storage tank (13) to remove light components and prevent polymerization.

9. A control system for gas phase recovery in a styrene process according to claim 5, characterized in that, The regulation and control module (2) links the monitored exhaust gas compressor inlet pressure frequency signal with the feedback signal of the online analysis module (7), and adjusts the flow rate of the absorbent circulation pump (4) according to the operating status of the exhaust gas compressor, which in turn affects the feed rate of the absorbent liquid to maintain the pressure balance of the system.

10. A control system for gas-phase recovery in a styrene process according to claim 5, characterized in that, A flow regulating valve is installed on the pipeline between the cascade heat exchange module (3) and the distributor (10). The control end of the flow regulating valve is electrically connected to the control output end of the regulating control module (2) and is used to adjust the feed rate of the absorbent according to the feedback signal of the online analysis module (7).

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