P-diethylbenzene recovery system

Abstract

The utility model relates to the technical field of petrochemical engineering, in particular to a p-diethylbenzene recovery system which comprises a p-diethylbenzene collecting tank, an air cooler, a p-diethylbenzene tank area, a steam heat exchanger, a carclazyte tower and a circulating pipeline, an outlet header pipe of the p-diethylbenzene collecting tank is connected to a p-diethylbenzene tank area through a first branch pipeline, the air cooler is arranged on the first branch pipeline, and the p-diethylbenzene tank area is sequentially connected with a steam heat exchanger and a carclazyte tower through a tank area outlet pipeline. An outlet of the carclazyte tower is connected to a p-diethylbenzene system through a p-diethylbenzene external supplement pipeline, an outlet sampler is arranged on the p-diethylbenzene external supplement pipeline, and the p-diethylbenzene external supplement pipeline is connected to an inlet of a p-diethylbenzene collecting tank through a circulating pipeline. According to the utility model, the outlet sampler is arranged at the outlet of the carclazyte tower, the treated diethylbenzene is sampled and detected, the diethylbenzene is circularly treated through the circulating pipeline, and after the diethylbenzene is monitored to be qualified, the diethylbenzene is merged into the system, so that the system is prevented from being polluted.

Description

Technical Field

[0001] This utility model relates to the field of petrochemical technology, specifically to a diethylbenzene recovery system. Background Technology

[0002] In the adsorption unit, p-diethylbenzene is a crucial desorbent in the adsorption tower system. During operation, small amounts of C8A and p-diethylbenzene produced, along with p-diethylbenzene after on-site sampling and replacement, are discharged into an underground tank. Because on-site sampling involves contact with air, it can lead to the production of carbonyl groups and bromine indices, causing the p-diethylbenzene to fail quality standards. When the underground tank level reaches 70%, sampling analysis reveals the presence of carbonyl groups and bromine indices, and the product is then discharged into the p-diethylbenzene tank area. When the unit system experiences a p-diethylbenzene system deficit, it can be replenished through the p-diethylbenzene tank area, but carbonyl and bromine indices must be removed. However, due to factors such as high space velocity in the clay tower, sometimes unqualified bromine and carbonyl groups enter the system, causing chronic poisoning of the adsorbent in the adsorption tower. Utility Model Content

[0003] In view of the defects of the existing technology, the purpose of this utility model is to provide a diethylbenzene recovery system, which samples and tests the recovered diethylbenzene to ensure that the bromine index and carbonyl group are qualified before putting it into the system, thereby ensuring the stability of the system.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a diethylbenzene recovery system, comprising a diethylbenzene collection tank, an air cooler, a diethylbenzene tank area, a steam heat exchanger, a clay tower, and a circulation pipeline; the outlet main pipe of the diethylbenzene collection tank is connected to the diethylbenzene tank area through a first branch pipeline, the air cooler is installed on the first branch pipeline, the diethylbenzene tank area is sequentially connected to the steam heat exchanger and the clay tower through the tank area outlet pipeline, the outlet of the clay tower is connected to the diethylbenzene system through a diethylbenzene external supply pipeline, an outlet sampler is installed on the diethylbenzene external supply pipeline, and the diethylbenzene external supply pipeline is connected to the inlet of the diethylbenzene collection tank through a circulation pipeline.

[0005] Furthermore, a first valve is installed on the first branch pipeline, and the first valve is located upstream of the air cooler.

[0006] Furthermore, the outlet main pipe of the p-diethylbenzene collection tank is connected to the p-diethylbenzene system through a second branch pipeline, and a second valve is installed on the second branch pipeline; the outlet of the second branch pipeline is connected to the downstream of the outlet sampler; an external supply valve is installed on the external supply pipeline, and the external supply valve is located downstream of the outlet of the second branch pipeline.

[0007] Furthermore, the inlet of the circulation pipeline is connected upstream of the outlet sampler; a circulation line valve is installed on the circulation pipeline.

[0008] Furthermore, a heat exchange outlet temperature gauge is installed downstream of the steam heat exchanger, and an air cooler outlet temperature gauge is installed downstream of the air cooler.

[0009] Furthermore, a centrifugal pump for a collection tank is installed on the outlet manifold.

[0010] Furthermore, a centrifugal pump is installed on the outlet pipeline of the tank area, and the centrifugal pump is connected to the outlet of the diethylbenzene tank area. The centrifugal pump is equipped with a pump outlet valve.

[0011] Furthermore, a flow control valve is installed on the outlet pipeline of the tank area, and the flow control valve is connected upstream of the steam heat exchanger.

[0012] Furthermore, the gas phase outlet at the top of the diethylbenzene collection tank is connected to the flare system via a gas phase emission pipeline.

[0013] Furthermore, the inlet of the diethylbenzene collection tank is connected to the desorbent discharge manifold, and the desorbent remaining in each container of the adsorption unit enters the diethylbenzene collection tank through the desorbent discharge manifold.

[0014] The beneficial effects of this utility model are as follows: The p-diethylbenzene recovery system of this utility model removes carbonyl and bromine index from heated p-diethylbenzene through a clay tower. An outlet sampler is installed at the outlet of the clay tower to sample and test the treated p-diethylbenzene. Qualified p-diethylbenzene is sent to the p-diethylbenzene system, while unqualified p-diethylbenzene is sent to the p-diethylbenzene collection tank through a circulation pipeline. It enters the p-diethylbenzene tank area together with newly collected p-diethylbenzene and is processed again through the clay tower until the carbonyl and bromine index are qualified. The p-diethylbenzene is then recycled through the circulation pipeline to achieve p-diethylbenzene recycling. After monitoring and confirming that it meets the qualification, it is then integrated into the system to prevent system contamination. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the diethylbenzene recovery system of this utility model;

[0016] In the diagram: 1. Diethylbenzene collection tank; 2. Air cooler; 3. Diethylbenzene tank area; 4. Steam heat exchanger; 5. Clay tower; 6. Circulation pipeline; 7. Main outlet pipe of the diethylbenzene collection tank; 8. First branch pipeline; 9. Tank area outlet pipeline; 10. External diethylbenzene supply pipeline; 11. Outlet sampler; 12. Heat exchanger outlet temperature gauge; 13. Air cooler outlet temperature gauge; 14. First valve; 15. Second branch pipeline; 16. Second valve; 17. Circulation line valve; 18. Collection tank centrifugal pump; 19. Tank area centrifugal pump; 20. Pump outlet valve; 21. Flow control valve; 22. Gas phase discharge pipeline; 23. External supply valve; 24. Desorbent discharge main pipe. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0018] See appendix Figure 1 A diethylbenzene recovery system includes a diethylbenzene collection tank 1, an air cooler 2, a diethylbenzene tank area 3, a steam heat exchanger 4, a clay tower 5, and a circulation pipeline 6. The outlet main pipe 7 of the diethylbenzene collection tank 1 is connected to the diethylbenzene tank area 3 via a first branch pipeline 8, on which the air cooler 2 is installed. The diethylbenzene tank area 3 is sequentially connected to the steam heat exchanger 4 and the clay tower 5 via a tank area outlet pipeline 9. The outlet of the clay tower 5 is connected to the diethylbenzene system via a diethylbenzene external supply pipeline 10, on which an outlet sampler 11 is installed. The diethylbenzene external supply pipeline 10 is connected to the inlet of the diethylbenzene collection tank 1 via the circulation pipeline 6. The outlet main pipe 7 of the diethylbenzene collection tank 1 is connected to the diethylbenzene system via a second branch pipeline 15. A heat exchange outlet temperature gauge 12 is installed downstream of the steam heat exchanger 4, and an air cooler outlet temperature gauge 13 is installed downstream of the air cooler 2.

[0019] Based on the above technical solution, during the operation of the adsorption unit, small amounts of C8A and para-diethylbenzene are intermittently discharged from the reflux tanks of each distillation column and other containers with residual desorbent. Para-diethylbenzene after on-site sampling and replacement is also discharged into para-diethylbenzene collection tank 1. Because on-site sampling involves contact with air, it can lead to the production of carbonyl groups and bromine indices, causing para-diethylbenzene to fail the test. When the liquid level in para-diethylbenzene collection tank 1 reaches 70%, a sample is taken for analysis. If the carbonyl groups and bromine indices are within acceptable limits, the system can be directly replenished from the deficit. If the sample analysis shows the presence of carbonyl groups and bromine indices, it is discharged into the para-diethylbenzene tank area. When the unit system is again deficient in para-diethylbenzene, it can be replenished through the tank area centrifugal pump, but carbonyl groups and bromine indices must be removed. After being heated to 130°C by steam heat exchanger 4, the carbonyl groups and bromine indices are removed by the clay tower 5. Only after passing the test is the material discharged into the system. If the desulfurization treatment in the white clay tower fails after sampling, the sample is sent to the p-diethylbenzene collection tank 1 via circulation pipeline 6. There, it enters the p-diethylbenzene tank area 3 along with newly collected p-diethylbenzene and is then processed again through the white clay tower 5 until the carbonyl and bromine index meet the requirements. The substandard p-diethylbenzene, after being heated by the steam heat exchanger 4, needs to be air-cooled by the air cooler 2 before being sent from the p-diethylbenzene collection tank 1 to the p-diethylbenzene tank area 3. The air cooler 2 is set to have an outlet temperature of 50°C.

[0020] Furthermore, in order to control the opening and closing of the first branch pipeline 8, a first valve 14 is provided on the first branch pipeline 8, and the first valve 14 is located upstream of the air cooler 2.

[0021] Furthermore, in order to control the on / off state of the second branch pipeline 15, a second valve 16 is installed on the second branch pipeline 15; the outlet of the second branch pipeline 15 is connected to the downstream of the outlet sampler, and can be directly sent to the diethylbenzene system through the second branch pipeline 15; an external supply valve 23 is installed on the external supply pipeline 10, which is located downstream of the outlet of the second branch pipeline and before the inlet of the diethylbenzene system. When the diethylbenzene system of the device system is deficient, the second valve 16 is opened to replenish the qualified diethylbenzene, and the unqualified diethylbenzene can also be cut off in time.

[0022] Furthermore, the inlet of the circulation pipeline 6 is connected upstream of the outlet sampler; a circulation line valve 17 is installed on the circulation pipeline 6. When the circulation line valve 17 is opened, the unqualified p-diethylbenzene from the outlet of the white clay tower 5 enters the p-diethylbenzene collection tank 1.

[0023] Furthermore, a collection tank centrifugal pump 18 is installed on the outlet manifold 7.

[0024] Furthermore, a tank area centrifugal pump 19 is installed on the tank area outlet pipeline 9. The tank area centrifugal pump 19 is connected to the outlet of the diethylbenzene tank area 3, and the tank area centrifugal pump 19 is equipped with a pump outlet valve 20.

[0025] Furthermore, a flow control valve 21 is installed on the tank area outlet pipeline 9, and the flow control valve 21 is connected upstream of the steam heat exchanger 4. The outlet temperature of the steam heat exchanger 4 can be controlled by the flow control valve 21.

[0026] Furthermore, the gas phase outlet at the top of the diethylbenzene collection tank 1 is connected to the flare system via a gas phase discharge pipeline 22.

[0027] Furthermore, the inlet of the p-diethylbenzene collection tank 1 is connected to the desorbent discharge manifold 24, and the desorbent remaining in each container of the adsorption unit enters the p-diethylbenzene collection tank 1 through the desorbent discharge manifold 24. The p-diethylbenzene collection tank 1 is an underground tank.

[0028] Loop processing procedure:

[0029] (1) Air cooler 2 is put into normal operation, and the outlet temperature is set to 50℃;

[0030] (2) Open the first valve 14, start the centrifugal pump 18 of the collection tank to feed the p-diethylbenzene tank area 3, and close the second valve 16, that is, close the p-diethylbenzene collection tank 1 to the p-diethylbenzene system process;

[0031] (3) Open the pump outlet valve 20 and start the tank area centrifugal pump 19 to feed the white clay tower 5;

[0032] (4) After confirming that the cold material has arrived, put steam heat exchanger 4 into operation and heat it to 130°C;

[0033] (5) Open the circulation line valve 17, that is, open the process from the white clay tower 5 to the diethylbenzene collection tank 1, and close the external supply valve 23, that is, close the process from the white clay tower 5 to the diethylbenzene system.

[0034] (6) Samples are taken periodically through the outlet sampler 11. The sample is considered qualified when the carbonyl and bromine index reach <20mgBr / 100g.

[0035] (7) After passing the test, open the external valve 23 to open the process from the white clay tower 5 to the diethylbenzene system, and close the circulation line valve 17 to close the process from the white clay tower 5 to the diethylbenzene collection tank 1.

[0036] (8) Stop the centrifugal pump 18 in the collection tank and stop the air cooler 2.

[0037] In this embodiment, diethylbenzene is self-circulated, and only after it reaches a qualified level is it incorporated into the system to prevent system contamination.

[0038] It should be noted that the parts of this utility model not described in detail are existing technologies.

[0039] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0040] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0041] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0042] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0043] The above-listed embodiments are merely preferred embodiments of this utility model. Obviously, this utility model is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this utility model should be considered within the protection scope of this utility model.

Claims

1. A diethylbenzene recovery system, characterized in that: The system includes a diethylbenzene collection tank, an air cooler, a diethylbenzene tank area, a steam heat exchanger, a clay tower, and a circulation pipeline. The outlet main of the diethylbenzene collection tank is connected to the diethylbenzene tank area via a first branch pipeline, on which the air cooler is installed. The diethylbenzene tank area is connected to the steam heat exchanger and the clay tower in sequence via a tank area outlet pipeline. The outlet of the clay tower is connected to the diethylbenzene system via a diethylbenzene external supply pipeline, on which an outlet sampler is installed. The diethylbenzene external supply pipeline is connected to the inlet of the diethylbenzene collection tank via a circulation pipeline.

2. The diethylbenzene recovery system according to claim 1, characterized in that: A first valve is installed on the first branch pipeline, and the first valve is located upstream of the air cooler.

3. The diethylbenzene recovery system according to claim 1, characterized in that: The main outlet pipe of the diethylbenzene collection tank is connected to the diethylbenzene system via a second branch line, and a second valve is installed on the second branch line; the outlet of the second branch line is connected to the downstream of the outlet sampler; an external supply valve is installed on the external supply line, and the external supply valve is located downstream of the outlet of the second branch line.

4. The diethylbenzene recovery system according to claim 1, characterized in that: The inlet of the circulation pipeline is connected upstream of the outlet sampler; a circulation line valve is installed on the circulation pipeline.

5. The diethylbenzene recovery system according to claim 1, characterized in that: A heat exchange outlet temperature gauge is installed downstream of the steam heat exchanger, and an air cooler outlet temperature gauge is installed downstream of the air cooler.

6. The diethylbenzene recovery system according to claim 1, characterized in that: A centrifugal pump for collecting tanks is installed on the outlet manifold.

7. The diethylbenzene recovery system according to claim 1, characterized in that: A centrifugal pump is installed on the outlet pipeline of the tank area, and the centrifugal pump is connected to the outlet of the diethylbenzene tank area. The centrifugal pump is equipped with a pump outlet valve.

8. The diethylbenzene recovery system according to claim 1, characterized in that: A flow control valve is installed on the outlet pipeline of the tank area, and the flow control valve is connected upstream of the steam heat exchanger.

9. A p-diethylbenzene recovery system according to claim 1, characterized in that: The gas phase outlet at the top of the diethylbenzene collection tank is connected to the flare system via a gas phase emission pipeline.

10. A p-diethylbenzene recovery system according to claim 1, characterized in that: The inlet of the diethylbenzene collection tank is connected to the desorbent discharge manifold, and the desorbent remaining in each container of the adsorption unit enters the diethylbenzene collection tank through the desorbent discharge manifold.

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