Cooling systems and fractionation towers for use in fractionation towers

Abstract

This disclosure relates to a cooling system for a fractionation column and a fractionation column. The cooling system includes: an oil and gas pipeline for containing oil and gas distilled from the top of the fractionation column; a first cooling device including a receiving cavity containing a cooling medium, wherein the oil and gas pipeline is at least partially disposed in the cooling medium; a first pipeline connected to the wall of the receiving cavity; and a storage tank disposed downstream of the first cooling device and connected to the end of the first pipeline away from the receiving cavity, for containing the cooling medium flowing out of the first cooling device. By placing the cooling medium in the cavity structure and immersing the oil and gas pipeline in the cooling medium to cool the oil and gas pipeline, the first cooling device is less prone to scaling and blockage, ensuring the cooling efficiency of the cooling system and preventing accidents such as cooling system shutdowns due to scaling of the cooling pipeline.

Description

Technical Field

[0001] This disclosure relates to the field of fractionation tower cooling technology, and more specifically, to a cooling system for a fractionation tower and a fractionation tower. Background Technology

[0002] Conventional distillation column top coolers typically employ either air or water coolers based on process requirements. However, for special operating conditions such as high temperatures in the vapor phase to be cooled at the top of the column, low heat loads, and the precipitated liquid phase being prone to condensation at low temperatures, conventional cooling systems present numerous problems. When the temperature of the vapor phase to be cooled at the top of the column is high, exceeding 200°C, using a water cooler can easily lead to scaling on the heat exchange tube bundles, resulting in decreased heat exchange efficiency. If an air cooler is used, not only does the fan in the air cooler occupy a large area, but uneven heat dissipation can also cause condensation of oil and gas inside the oil and gas pipelines at the top of the column, leading to wax buildup in the oil and gas pipelines and affecting the long-term operation of the equipment. Utility Model Content

[0003] The purpose of this disclosure is to provide a cooling system and a fractionating tower for a distillation tower, in order to solve the problems of conventional cooling measures in the related art, such as the difficulty in selecting air coolers; the large influence of seasonal and environmental conditions on air coolers, resulting in unstable and difficult-to-control temperatures after cooling; scaling of heat exchange tube bundles in water coolers, leading to a decrease in heat exchange efficiency and affecting long-term operation of the equipment; and the easy condensation of precipitated liquid phase in air coolers and water coolers, causing pipeline blockage.

[0004] To achieve the above objectives, this disclosure provides a cooling system for a fractionation column, comprising: Oil and gas pipelines are used to contain the oil and gas distilled from the top of the fractionation tower; The first cooling device includes a receiving cavity containing a cooling medium, and the oil and gas pipeline is at least partially disposed in the cooling medium; The first conduit is connected to the wall of the receiving cavity; The second pipeline is connected to the cavity wall of the receiving cavity and is capable of providing the cooling medium to the receiving cavity; The third pipe is connected to the cavity wall of the receiving cavity and is capable of discharging the cooling medium inside the receiving cavity; A liquid storage tank is located downstream of the first cooling device and connected to the end of the first pipeline away from the receiving cavity, for containing the cooling medium flowing out of the first cooling device; A flow detection element and a first control valve are installed on the second pipeline, and the flow detection element and the first control valve form a flow control loop. The oil and gas pipeline includes a discharge section, a temperature detection element is installed on the discharge section, and a second control valve is installed on the third pipeline; a liquid level detection element is installed on the cavity wall; the temperature detection element, the liquid level detection element, and the second control valve form a temperature-liquid level cascade control loop. Optionally, the first conduit is connected to the top of the receiving cavity, and the third conduit is connected to the bottom of the receiving cavity.

[0005] Optionally, the liquid storage tank includes: The liquid storage tank body is used to contain the cooling medium flowing out of the containing cavity; and The drain pipe is connected to the bottom of the liquid storage tank body in an openable and closable manner.

[0006] Optionally, the liquid storage tank further includes an exhaust pipe that is closable and connected to the top of the liquid storage tank body.

[0007] Optionally, the cooling system further includes a second cooling device disposed on the first pipeline for cooling the first pipeline.

[0008] Optionally, the oil and gas pipeline includes: Feeding section; and A cooling section is connected downstream of the feeding section and is located in the first cooling device, and is at least partially in contact with the cooling medium; the discharge section is connected downstream of the cooling section.

[0009] According to another aspect of this disclosure, a fractionating tower includes a fractionating tower body and the aforementioned cooling system for the fractionating tower.

[0010] The above technical solution places the cooling medium within the cavity structure and places the oil and gas pipelines within the cooling medium to cool the oil and gas in the pipelines. This is suitable for applications where the temperature of the material to be cooled is high and the required cooling load is low. It features flexible and adjustable outlet temperature and a wide applicable temperature range. It not only meets the cooling requirements of the oil and gas in the pipelines, but also, because the cooling medium is located within the cavity, its temperature is relatively stable compared to structures where the cooling medium is located within the pipelines. This also prevents scaling and blockage of the first cooling unit, ensuring the cooling efficiency of the cooling system and avoiding shutdowns caused by scaling in the cooling pipelines. Compared to air coolers that rely on localized cooling via fans, this solution reduces the footprint, avoids temperature fluctuations after cooling due to changes in environmental conditions, and prevents blockages caused by uneven cooling of the oil and gas in the pipelines due to wax buildup at multiple points. The overall cooling system has a simple structure and a high degree of automation, effectively reducing investment and energy consumption.

[0011] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0012] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of a cooling system for a distillation tower according to one embodiment of the present disclosure.

[0013] Explanation of reference numerals in the attached figures 1-Oil and gas pipeline; 11-Feeding section; 12-Cooling section; 13-Discharge section; 2-First cooling device; 21-Cavity wall; 22-Second pipeline; 221-First control valve; 222-Second control valve; 23-Third pipeline; 3-First pipeline; 4-Storage tank; 40-Storage tank body; 41-Drainage pipeline; 42-Exhaust pipeline; 5-Second cooling device; 6-Temperature detection element; 7-Level detection element; 8-Flow detection element. Detailed Implementation

[0014] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0015] In this disclosure, unless otherwise stated, directional terms such as "upper" and "lower" are defined in relation to the overall arrangement of the cooling system, and "inner" and "outer" are defined in relation to the outline of the corresponding components. The terms "first," "second," etc., are used to distinguish different components and do not imply sequentiality or importance. Furthermore, in the following description, when referring to the accompanying drawings, unless otherwise explained, the same reference numerals in different drawings denote the same or similar elements.

[0016] In related technologies, oil and gas flowing out of the distillation tower are cooled using conventional air coolers or water coolers. However, for the top of the distillation tower, where the temperature of the gas phase to be cooled is high, the heat load is low, and the liquid phase precipitated from the cooling tower is prone to condensation at low temperatures, the selection of coolers presents challenges such as difficulty in selecting standard air coolers, high customization costs, and large footprint; water cooler tube bundles are prone to scaling; and the oil and gas pipelines of both air coolers and water coolers are prone to condensation and blockage.

[0017] According to one embodiment of this disclosure, such as Figure 1As shown, a cooling system for a fractionation tower is provided, including an oil / gas pipeline 1, a first cooling device 2, a first pipeline 3, a second pipeline 22, a third pipeline 23, and a storage tank 4. The oil / gas pipeline 1 can be used to contain the oil / gas distilled from the top of the fractionation tower; the first cooling device 2 may include a receiving cavity containing a cooling medium, and the oil / gas pipeline 1 is at least partially disposed within the cooling medium. The first pipeline 3 can be connected to the cavity wall 21 of the receiving cavity, enabling the discharge of vaporized cooling medium from the receiving cavity; the second pipeline 22 can be connected to the cavity wall 21 of the receiving cavity, enabling the supply of cooling medium to the receiving cavity; and the third pipeline 23 can be connected to the cavity wall 21 of the receiving cavity, enabling the discharge of cooling medium from the receiving cavity. The storage tank 4 can be located downstream of the first cooling device 2 and connected to the end of the first pipeline 3 furthest from the receiving cavity, for containing the cooling medium flowing out of the first cooling device 2. The flow detection element 8 and the first control valve 221 are installed on the second pipeline 22. The flow detection element 8 and the first control valve 221 form a flow control loop. The oil and gas pipeline 1 includes a discharge section 13. The temperature detection element 6 is installed on the discharge section 13. The second control valve 222 is installed on the third pipeline 23. The liquid level detection element 7 is installed on the cavity wall 21. The temperature detection element 6, the liquid level detection element 7, and the second control valve 222 form a temperature-liquid level cascade control loop.

[0018] The above technical solution places the cooling medium within the cavity structure and places the oil-gas pipeline 1 within the cooling medium to cool the oil and gas within it. This is suitable for applications where the temperature of the material to be cooled is high and the required cooling load is low. It features flexible and adjustable outlet temperature and a wide applicable temperature range. It not only satisfies the cooling requirements of the oil and gas in the oil-gas pipeline 1, but also, because the cooling medium is located within the cavity, its temperature is relatively stable compared to structures where the cooling medium is located within pipelines. This also prevents scaling and blockage of the first cooling device 2, ensuring the cooling efficiency of the cooling system and avoiding shutdowns caused by scaling in the cooling pipelines. Compared to air coolers that rely on localized cooling via a fan, this solution reduces the floor space required, avoids temperature fluctuations after cooling due to changes in environmental conditions, and prevents blockages caused by uneven cooling of the oil and gas within the oil-gas pipeline 1 due to wax buildup at multiple points. The overall cooling system has a simple structure and a high degree of automation, effectively reducing investment and energy consumption.

[0019] Here, the first control valve 221 can be used to control the opening and closing of the second pipeline 22. Based on the data obtained by the flow detection element 8, the flow rate of the second pipeline 22 can be increased or decreased by the first control valve 221 to control the capacity of the cooling medium in the containment cavity, so as to control the cooling degree of the oil-gas pipeline 1 as needed. The connection between the first control valve 221 and the flow detection element 8 can be an electrical connection or a signal connection, which is not limited in this disclosure.

[0020] In addition, the temperature detection element 6 is connected to the second control valve 222, thereby judging the cooling status in the oil-gas pipeline 1 based on the temperature of the discharge section 13, and feeding back the cooling status to the second control valve 222 to control the inflow of cooling medium. When the temperature of the discharge section 13 is too high, it indicates that the oil and gas in the oil-gas pipeline 1 is not cooled sufficiently, and the second control valve 222 needs to control the third pipeline 23 to reduce the outflow of cooling medium, thereby increasing the contact area between the cooling section 12 and the cooling medium, and thus achieving a better cooling effect. If the temperature detection element 6 is electrically connected to the first control valve 221, the first control valve 221 can also control the second pipeline 22 to increase the inflow of cooling medium, and this disclosure does not limit this. When the temperature of the discharge section 13 is too low, it indicates that the required cooling effect has been achieved, and the inflow of cooling medium can be appropriately reduced or the outflow of cooling medium can be increased to reduce the contact area between the cooling section 12 and the cooling medium, thereby reducing energy waste while maintaining the cooling effect.

[0021] The liquid level detection element 7 is connected to the second control valve 222 and the temperature detection element 6, respectively, and can monitor the liquid level of the cooling medium in the first cooling device 2. When the temperature detection element 6 detects that the temperature of the discharge section 13 is too high, the second control valve 222 can control the third pipeline 23 to reduce the discharge flow of the cooling medium, increase the liquid level of the cooling medium in the first cooling device 2, thereby increasing the contact area between the cooling section 12 and the cooling medium, and thus achieving a better cooling effect. When the temperature detection element 6 detects that the temperature of the discharge section 13 is too low, it indicates that the required cooling effect has been achieved, and the inflow of the cooling medium can be appropriately reduced to lower the liquid level of the cooling medium in the first cooling device 2, reduce the contact area between the cooling section 12 and the cooling medium, and increase the temperature after cooling. Here, the temperature detection element 6 can be a thermometer or a temperature sensor, and the liquid level detection element 7 can be a level gauge or a level sensor; this disclosure does not limit this. It should be noted that the connection between the second control valve 222 and the temperature detection element 6 and the liquid level detection element 7 can be an electrical connection or a signal connection; this disclosure does not limit this.

[0022] Furthermore, such as Figure 1 As shown, the first pipe 3 can be connected to the top of the receiving cavity, and the third pipe 23 can be connected to the bottom of the receiving cavity. In actual production, the cooling medium can be demineralized water or deoxygenated water. Due to the high temperature of the oil and gas in the oil and gas pipeline 1, the cooling medium may reach its boiling point, causing partial vaporization of the cooling medium in the receiving cavity. Since the gas density is less than the liquid density, the vaporized cooling medium will accumulate at the top of the receiving cavity. Connecting the first pipe 3 to the top of the receiving cavity makes it easier to discharge the vaporized cooling medium.

[0023] According to one embodiment of this disclosure, such as Figure 1As shown, the storage tank 4 may include a storage tank body 40 for containing the cooling medium flowing out of the receiving cavity and a drain pipe 41 that is openable and closable connected to the bottom of the storage tank body 40. In this way, the cooling medium can be discharged in a timely manner through the drain pipe 41 according to the capacity of the storage tank body 40 and the volume of the cooling medium stored, so that the storage tank body 40 can continue to store the cooling medium cooled by the second cooling device 5.

[0024] Furthermore, such as Figure 1 As shown, the storage tank 4 may further include an exhaust pipe 42, which is closable and connectable to the top of the storage tank body 40. Here, an adjustable valve may be provided on the exhaust pipe 42 to regulate the pressure within the first cooling device 2 and the storage tank 40 housing. According to one embodiment of this disclosure, as... Figure 1 As shown, the cooling system may further include a second cooling device 5, which can be installed on the first pipeline 3 to cool the first pipeline 3. The second cooling device 5 can be a vapor phase cooler, which can be water-cooled or air-cooled; this disclosure does not limit this. Since the oil and gas temperature in the oil and gas pipeline 1 is high, the cooling medium flowing out of the first cooling device 2 is usually in vapor form. By connecting a second cooling device 5 to the first cooling device 2, which cools the oil and gas pipeline 1 circulating outside the fractionation tower, the vapor-like cooling medium flowing out of the first cooling device 2 is cooled, causing it to liquefy and flow into the storage tank 4 for collection. This avoids the situation where smoke surrounds the outside of the fractionation tower, affecting the visibility of the workers, improving the accuracy of on-site operations, and also preventing safety accidents caused by excessively high temperatures of the vapor-like cooling medium dissipating into the outside.

[0025] Furthermore, such as Figure 1As shown, the oil and gas pipeline 1 may include a feed section 11, a cooling section 12, and a discharge section 13. The cooling section 12 may be connected downstream of the feed section 11 and is located within the first cooling device 2, at least partially in contact with the cooling medium. Here, when the cooling medium is initially in a liquid state, the cooling section 12 may be fully submerged in the cooling medium or partially submerged, depending on the cooling requirements; this disclosure does not limit this. The discharge section 13 may be connected downstream of the cooling section 12. Here, the connection between the feed section 11 and the cooling section 12, and the connection between the discharge section 13 and the cooling section 12, may be located within a receiving cavity, or both connections may be located at the cavity wall 21; this disclosure does not limit this. Furthermore, the cooling section 12 may include multiple parallel corrugated pipes; the number of corrugated pipes may be four or eight; this disclosure does not limit this. The corrugated pipes allow for greater contact between the oil and gas in the oil and gas pipeline 1 and the cooling medium. In addition, the design of the cooling section 12 as a spiral pipe, as well as the structure of the coexistence of spiral pipe and corrugated pipe, are also within the scope of protection of this disclosure.

[0026] Based on the above-described solution, this disclosure also provides a fractionating tower, which includes the aforementioned cooling system for the fractionating tower. Both ends of the oil / gas pipeline 1 can be connected to the fractionating tower body, and the outlet section 13 of the oil / gas pipeline 1 can also be connected to other downstream fractionating towers or storage tanks, or other equipment. Furthermore, this fractionating tower possesses all the beneficial effects of the aforementioned cooling system for fractionating towers, which will not be elaborated upon here.

[0027] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0028] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0029] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A cooling system for a fractionation column, characterized by, include: Oil and gas pipelines are used to contain the oil and gas distilled from the top of the fractionation tower; The first cooling device includes a receiving cavity containing a cooling medium, and the oil and gas pipeline is at least partially disposed in the cooling medium; The first conduit is connected to the wall of the receiving cavity; The second pipeline is connected to the cavity wall of the receiving cavity and is capable of providing the cooling medium to the receiving cavity; The third pipe is connected to the cavity wall of the receiving cavity and is capable of discharging the cooling medium inside the receiving cavity; A liquid storage tank is located downstream of the first cooling device and connected to the end of the first pipeline away from the receiving cavity, for containing the cooling medium flowing out of the first cooling device; A flow detection element and a first control valve are installed on the second pipeline, and the flow detection element and the first control valve form a flow control loop. The oil and gas pipeline includes a discharge section, a temperature detection element is installed on the discharge section, a second control valve is installed on the third pipeline, and a liquid level detection element is installed on the cavity wall. The temperature detection element, the liquid level detection element, and the second control valve form a temperature-liquid level cascade control loop.

2. The cooling system for a distillation tower according to claim 1, characterized in that, The first conduit is connected to the top of the receiving cavity, and the third conduit is connected to the bottom of the receiving cavity.

3. The cooling system for a distillation tower according to claim 1, characterized in that, The liquid storage tank includes: The liquid storage tank body is used to contain the cooling medium flowing out of the containing cavity; and The drain pipe is connected to the bottom of the liquid storage tank body in an openable and closable manner.

4. The cooling system for a distillation tower according to claim 3, characterized in that, The storage tank also includes an exhaust pipe that is closable and connected to the top of the storage tank body.

5. The cooling system for a distillation tower according to claim 1, characterized in that, The cooling system further includes a second cooling device, which is disposed on the first pipeline and is used to cool the first pipeline.

6. The cooling system for a distillation tower according to claim 1, characterized in that, The oil and gas pipeline includes: Feeding section; and A cooling section is connected downstream of the feeding section and is located in the first cooling device, and is at least partially in contact with the cooling medium; the discharge section is connected downstream of the cooling section.

7. A fractionation tower, characterized in that, It includes the fractionation tower body and the cooling system for the fractionation tower as described in any one of claims 1-6.

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