Coking fractionation system capable of preventing and controlling coking
By designing a liquid spraying mechanism, vertical cylinder, gas distributor, spraying mechanism and an inclined heavy wax oil collection tank in the coking fractionation system, the effective removal of the coking components in the reaction oil and gas is achieved, and the problem of coking in the heavy wax oil section is solved, and the normal operation of the equipment and product quality are improved.
Patent Information
- Application Number
- CN202421755905.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-24
- Publication Date
- 2025-04-11
- Estimated Expiration
- 2034-07-24
AI Technical Summary
In the existing coking fractionation system, the washing effect of raw oil is poor, and it is impossible to effectively remove coking components such as coking powder, colloids and asphaltene in the reaction oil and gas, resulting in coking in the heavy wax oil section, which affects the normal operation of the equipment and product quality.
A coking fractionation system including a liquid spraying mechanism, a vertical cylinder, a gas distributor, a spraying mechanism and an inclined heavy wax oil collection tank is designed. Through the washing process of two reverse contacts, the coking components in the reaction oil and gas are effectively removed, and the coking powder is prevented from deposition and coking through the inclined design of the heavy wax oil collection tank and the use of the liquid spraying mechanism.
It improves the washing effect, effectively prevents coking in the heavy wax oil section, and ensures the long-term normal operation of the equipment and the improvement of product quality.
Smart Images
Figure CN222744253U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of coking fractionation, and in particular to a coking fractionation system capable of preventing and controlling coking. Background Art
[0002] The main function of the coking fractionation system is to separate the reaction oil and gas from the coke tower into wax oil, diesel, gasoline, rich gas and other products, so as to further process them as raw materials for downstream devices. The fractionation tower is the main equipment of the coking fractionation system. Its lower part is mainly composed of the reaction oil and gas feed section, the upper and lower feeds of the raw oil, the herringbone baffle, the heavy wax oil pump, the heavy wax oil collecting tank, the heavy wax oil lower reflux section, and the heavy wax oil upper reflux section. The raw oil upper feed enters the herringbone baffle at the bottom of the fractionation tower and exchanges heat with the reaction oil and gas. The heavy wax oil section does not have a heat exchanger to extract heat.
[0003] The distillation tower uses the feed of raw oil as washing oil, but the content of colloid and asphalt in the raw oil is relatively high, and the washing effect is poor. It cannot effectively remove the coke powder, colloid and asphalt in the reaction oil and gas, which are easy to coke. These coke-forming components are carried into the heavy wax oil section, resulting in the problem of coking in the heavy wax oil collecting tank, making it difficult for the heavy wax oil section to operate normally, and then the reaction oil and gas directly enter the wax oil product section without separation in the heavy wax oil section, which reduces the quality of the wax product; secondly, a simple bottom oil circulation pump cannot ensure that the bottom oil maintains good fluidity when the bottom temperature is not controlled smoothly. Coke powder causes serious coking at the bottom of the distillation tower, which makes the distillation tower unable to operate normally for a long time, reducing the economic benefits of the enterprise; in addition, the liquid residence time of the heavy wax oil collecting tank is generally relatively long. In actual operation, the liquid level control of the collecting tank is relatively high, which makes the liquid difficult to flow and easily causes solid deposition. Long-term operation is prone to blockage of the heavy wax oil extraction port due to excessive accumulation of solids. Therefore, it is an objective need to develop a coking fractionation system that has good washing effect, can improve product quality, and can ensure the long-term normal operation of the equipment and can prevent and control coking. Utility Model Content
[0004] The utility model aims to provide a coking fractionation system which has good washing effect, can improve product quality, can ensure long-term normal operation of equipment and can prevent and control coking.
[0005] The purpose of the utility model is achieved in this way, including a distillation tower, a heat exchanger and a raw oil tank, wherein a liquid spraying mechanism, a vertical tube, a gas distributor, a spraying mechanism and an inclined heavy wax oil collecting tank are sequentially arranged in the distillation tower from bottom to top, the liquid spraying direction of the liquid spraying mechanism is toward the bottom of the distillation tower, both ends of the vertical tube are blocked, a plurality of air outlet holes are evenly processed on the side wall of the vertical tube, the lower end of the vertical tube is connected with an air inlet pipe extending to the outside of the distillation tower, a spiral half-tube is arranged on the side wall of the distillation tower around the vertical tube, a plurality of liquid outlet holes are processed on the spiral half-tube, a wax oil extraction pipe of the heavy wax oil collecting tank is connected to the hot medium inlet of the heat exchanger, the hot medium outlet of the heat exchanger is connected to the liquid inlet of the liquid spraying mechanism, the outlet of the raw oil tank is connected to the cold medium inlet of the heat exchanger, and the cold medium outlet of the heat exchanger is respectively connected to the liquid inlets of the spraying mechanism and the spiral half-tube.
[0006] Furthermore, a semi-annular pipe is coaxially arranged on the outside of the distillation tower, and the outside of the semi-annular pipe is connected to the wax oil extraction pipe through a pipeline. A number of nozzles are evenly spaced on the inside of the semi-annular pipe, and the nozzles are connected to the distillation tower above the chassis of the heavy wax oil collecting tank, and the spray direction of the nozzles is toward the lower end of the heavy wax oil collecting tank.
[0007] Furthermore, a jacket is provided on the outer wall of the distillation tower below the vertical cylinder.
[0008] Furthermore, the jacket is divided into two independent chambers by a partition, the outlet and the inlet of the jacket are respectively arranged on the two chambers, and a plurality of heat exchange tubes are arranged between the two chambers, and the heat exchange tubes are located in the distillation tower.
[0009] Furthermore, a gas-liquid mixer is arranged outside the distillation tower, the liquid inlet of the gas-liquid mixer is connected to the heat medium outlet of the heat exchanger, the gas inlet of the gas-liquid mixer is connected to the steam pipeline, and the outlet of the gas-liquid mixer is connected to the liquid injection mechanism.
[0010] Furthermore, a filter is provided on the wax oil extraction pipe between the heavy wax oil collecting tank and the heat medium inlet of the heat exchanger.
[0011] Furthermore, the outlet of the crude oil tank is tangentially connected to the side wall of the distillation tower below the vertical cylinder through a pipeline.
[0012] When the utility model is in operation, the reaction oil and gas from the coke tower enters the vertical cylinder, and then is sprayed to the surroundings from the air outlet holes on the side wall of the vertical cylinder. At the same time, the raw oil is sprayed from the liquid outlet holes of the spiral half-tube, and the oil mist is reversely contacted with the reaction oil and gas for the first time. The oil mist washes the reaction oil and gas for the first time to remove some of the coke powder, colloid, asphaltene and other easy-to-coke components in the reaction oil and gas. Subsequently, the reaction oil and gas pass through the gas distributor, and the gas distributor makes the reaction oil and gas evenly distributed on the cross section of the distillation tower, and then is reversely contacted with the oil mist sprayed by the spray mechanism for the second time. The oil mist washes the reaction oil and gas for the second time to remove some of the coke powder, colloid, asphaltene and other easy-to-coke components in the reaction oil and gas again. Subsequently, the reaction oil and gas continue to rise for subsequent distillation processes. In the above process, the washing mechanism of the reaction oil and gas has a compact structure, so that the reaction oil and gas are washed twice in succession, with a good washing effect, and can better remove the coke-prone components such as coke powder, colloid and asphalt in the reaction oil and gas, and prevent these components from entering the heavy wax oil section, causing the problem of coking in the heavy wax oil collecting tank, ensuring the normal operation of the heavy wax oil section, so that the reaction oil and gas can be separated from the heavy wax oil section and then enter the wax oil product section, thereby improving the quality of the wax product; secondly, the heavy wax oil collecting tank in the utility model is inclined, and the deposited coke powder and other impurities can be removed. Under the action of gravity, it flows toward the wax oil extraction pipe, thereby preventing coke powder and the like from being deposited in the heavy wax oil collection tank, ensuring the unobstructed heavy wax oil extraction port; in addition, a liquid spraying mechanism is also provided in the utility model, which can spray the wax oil to the bottom of the fractionation tower, preventing coke powder and other impurities from being deposited at the bottom of the fractionation tower, and stirring the bottom oil of the fractionation tower at the same time, so that the bottom oil maintains a certain disturbance and flow state, and has a certain fluidity, thereby preventing the coke powder deposition from causing the problem of coking at the bottom of the fractionation tower, so that the fractionation tower can operate normally for a long time, and improve the economic benefits of the enterprise. In summary, the utility model has the advantages of good washing effect, can improve product quality, can ensure the long-term normal operation of equipment, and can prevent and control coking. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the overall structure of the utility model;
[0014] Figure 2 It is a structural schematic diagram of the semi-annular tube 13 in the utility model;
[0015] In the figure: 1-distillation tower, 2-heat exchanger, 3-raw oil tank, 4-liquid spraying mechanism, 5-vertical cylinder, 6-gas distributor, 7-spraying mechanism, 8-heavy wax oil collecting tank, 9-inlet pipe, 10-spiral half pipe, 11-wax oil extraction pipe, 12-filter, 13-semi-annular pipe, 14-spraying pipe, 15-jacket, 16-partition, 17-heat exchange tube, 18-gas-liquid mixer, 19-steam pipeline. DETAILED DESCRIPTION
[0016] The present invention is further described below in conjunction with the accompanying drawings, but the present invention is not limited in any way. Any changes or improvements made based on the present invention belong to the protection scope of the present invention.
[0017] like Figures 1-2 As shown, the utility model includes a fractionating tower 1, a heat exchanger 2 and a raw oil tank 3. The heat exchanger 2 and the raw oil tank 3 are existing equipment. The heat exchanger 2 can be a shell and tube structure. When in use, the wax oil extracted from the heavy wax oil collecting tank 8 can be sent to the tube side of the heat exchanger 2, and the raw oil can be passed into the shell side of the heat exchanger 2 to reduce the temperature of the wax oil through the raw oil. The raw oil tank 3 is used to store the raw oil. The fractionating tower 1 is provided with a liquid spraying mechanism 4, a vertical cylinder 5, a gas distributor 6, a spraying mechanism 7 and an inclined heavy wax oil collecting tank 8 from bottom to top. The liquid spraying mechanism 4, the gas distributor 6, the spraying mechanism 7 and the heavy wax oil collecting tank 8 are existing technologies. The liquid spraying mechanism 4 is used to spray liquid, the gas distributor 6 is used to evenly react the distribution of oil and gas in the fractionating tower 1, and the spraying mechanism 7 is used to spray oil mist, the heavy wax oil collecting tank 8 is used to collect wax oil, the liquid spraying direction of the liquid spraying mechanism 4 is toward the bottom of the distillation tower 1, the two ends of the vertical cylinder 5 are blocked, and a number of air outlet holes are evenly processed on the side wall of the vertical cylinder 5. The lower end of the vertical cylinder 5 is connected with an air inlet pipe 9 extending to the outside of the distillation tower 1, and a spiral half-tube 10 is arranged on the side wall of the distillation tower 1 around the vertical cylinder 5. The spiral half-tube 10 is processed with a number of liquid outlet holes, the wax oil extraction pipe 11 of the heavy wax oil collecting tank 8 is connected to the hot medium inlet of the heat exchanger 2, the hot medium outlet of the heat exchanger 2 is connected to the liquid inlet of the liquid spraying mechanism 4, the outlet of the raw oil tank 3 is connected to the cold medium inlet of the heat exchanger 2, and the cold medium outlet of the heat exchanger 2 is respectively connected to the liquid inlets of the spraying mechanism 7 and the spiral half-tube 10.
[0018] When the utility model is in operation, the reaction oil and gas from the coke tower enters the vertical cylinder 5 through the air inlet pipe 9, and then is sprayed to the surroundings from the air outlet holes on the side wall of the vertical cylinder 5. At the same time, the raw oil is sprayed from the liquid outlet holes of the spiral half tube 10, and the oil mist is reversely contacted with the reaction oil and gas for the first time. The oil mist washes the reaction oil and gas for the first time to remove some of the coke powder, colloid, asphaltene and other easy-to-coke components in the reaction oil and gas. Subsequently, the reaction oil and gas pass through the gas distributor 6, and the gas distributor 6 makes the reaction oil and gas evenly distributed on the cross section of the fractionation tower 1, and then is reversely contacted with the oil mist sprayed from the spray mechanism 7 for the second time. The oil mist washes the reaction oil and gas for the second time to remove some of the coke powder, colloid, asphaltene and other easy-to-coke components in the reaction oil and gas again. Subsequently, the reaction oil and gas continues to rise for subsequent fractionation processes. In the above process, the washing mechanism of the reaction oil and gas has a compact structure, so that the reaction oil and gas are washed twice in succession, with a good washing effect, and can better remove the coke powder, colloid and asphaltene and other easy-to-coke components in the reaction oil and gas, and prevent these components from entering the heavy wax oil section, causing the heavy wax oil collecting tank 8 to produce coking problems, ensuring that the heavy wax oil section can operate normally, so that the reaction oil and gas can be separated from the heavy wax oil section and then enter the wax oil product section, thereby improving the quality of the wax product; secondly, the heavy wax oil collecting tank 8 in the utility model is tilted, and the deposited coke powder and other impurities can flow toward the wax oil extraction pipe 11 under the action of gravity, thereby preventing the coke powder and the like from being deposited in the heavy wax oil collecting tank 8. In the oil tank 8, the heavy wax oil extraction outlet is ensured to be unobstructed. The chassis of the heavy wax oil collecting tank 8 adopts an inclined design, which can minimize the influence of the deposition of coke powder in the heavy wax oil collecting tank 8 on the effective residence time and liquid level observation and control of the heavy wax oil collecting tank 8; in addition, a liquid spraying mechanism 4 is also provided in the utility model. The liquid spraying mechanism 4 can spray wax oil to the bottom of the distillation tower 1 to prevent impurities such as coke powder from being deposited at the bottom of the distillation tower 1, and at the same time stir the bottom oil of the distillation tower 1 so that the bottom oil maintains a certain disturbance and flow state and has a certain fluidity, thereby preventing the problem of coking at the bottom of the distillation tower 1 caused by the deposition of coke powder, so that the distillation tower 1 can operate normally for a long time and improve the economic benefits of the enterprise.
[0019] A semi-circular pipe 13 is coaxially arranged on the outside of the fractionation tower 1, and the outside of the semi-circular pipe 13 is connected to the wax oil extraction pipe 11 through a pipeline. A plurality of nozzles 14 are evenly spaced on the inside of the semi-circular pipe 13, and the nozzles 14 are connected to the fractionation tower 1 above the chassis of the heavy wax oil collecting tank 8, and the spray direction of the nozzles 14 is toward the lower end of the heavy wax oil collecting tank 8. When in use, the wax oil extracted from the wax oil extraction pipe 11 passes into the semi-circular pipe 13, and then flows into each nozzle 14, and finally sprays out from the nozzle 14, forming a water flow at the bottom of the heavy wax oil collecting tank 8, and these water flows rush to the bottom of the heavy wax oil collecting tank 8, promote the flow of the wax oil at the bottom of the heavy wax oil collecting tank 8, and rush the precipitated coke powder and other impurities to the direction of the wax oil extraction pipe 11, and are discharged in time through the wax oil extraction pipe 11, so as to prevent the formation of coke in the heavy wax oil collecting tank 8.
[0020] A jacket 15 is provided on the outer wall of the distillation tower 1 below the vertical cylinder 5. The jacket 15 is an existing structure. In the utility model, a low-temperature medium is introduced into the jacket 15 to quickly take away part of the heat of the raw oil at the bottom of the distillation tower 1, reduce the temperature of the raw oil, and prevent the formation of coking.
[0021] The jacket 15 is divided into two independent chambers by a partition 16. The outlet and inlet of the jacket 15 are respectively arranged on the two chambers. A plurality of heat exchange tubes 17 are arranged between the two chambers. The heat exchange tubes 17 are located in the fractionation tower 1. When in use, the low-temperature medium first enters one of the chambers from the inlet, and then flows into the other chamber through the heat exchange tubes 17. When the low-temperature medium is in the two chambers, it absorbs the heat of the bottom raw oil from the outside of the fractionation tower 1. When the low-temperature medium flows in the heat exchange tubes 17, it absorbs the heat from the inside of the bottom raw oil. In this way, the heat is absorbed from both the outside and the inside of the raw oil, which can reduce the temperature of the bottom raw oil more quickly and further prevent the generation of coking.
[0022] A gas-liquid mixer 18 is arranged outside the fractionation tower 1. The gas-liquid mixer 18 is an existing device used for mixing gas and liquid. The liquid inlet of the gas-liquid mixer 18 is connected to the heat medium outlet of the heat exchanger 2, the gas inlet of the gas-liquid mixer 18 is connected to the steam pipeline 19, and the outlet of the gas-liquid mixer 18 is connected to the liquid spraying mechanism 4. In the utility model, the wax oil discharged from the heat medium outlet of the heat exchanger 2 and the steam discharged from the steam pipeline 19 are sent to the gas-liquid mixer 18 for mixing, and then the mixed gas-liquid mixture is sprayed into the liquid spraying mechanism 4 together. While stirring the raw oil at the bottom of the fractionation tower 1 to prevent impurities such as coke powder from coking, due to the presence of steam, bubbles can be generated in the raw oil to form pneumatic stirring, which further makes the raw oil at the bottom of the fractionation tower 1 in a flowing state, ensuring that there is no coking problem at the bottom of the fractionation tower 1.
[0023] A filter 12 is provided on the wax oil extraction pipe 11 between the heavy wax oil collecting tank 8 and the heat medium inlet of the heat exchanger 2. The filter 12 is an existing device and is used in the utility model to filter the coke powder in the wax oil to avoid the blockage of subsequent pipelines and equipment caused by the coke powder, and to greatly reduce the coke powder content in the wax oil, thereby reducing the possibility of coking of the coke powder during subsequent use.
[0024] The outlet of the crude oil tank 3 is tangentially connected to the side wall of the distillation tower 1 below the vertical cylinder 5 through a pipeline, and the crude oil is sent tangentially into the lower part of the distillation tower 1, which has two functions: one is to drive the crude oil in the distillation tower 1 to form a vortex, so that it is in a continuous flow state, to prevent the precipitation of coke powder, and then to prevent the formation of coking; the second is that the crude oil comes from the crude oil tank 3, and its own temperature is relatively low. After passing into the distillation tower 1, the temperature of the crude oil at the bottom of the tower can be reduced, and the medium with high asphaltene content and poor thermal stability can be prevented from cracking and condensing to cause coking.
Claims
1. A coking fractionation system capable of preventing and controlling coking, comprising a fractionation tower (1), a heat exchanger (2) and a raw oil tank (3), characterized in that The fractionation tower (1) is provided with a liquid spraying mechanism (4), a vertical tube (5), a gas distributor (6), a spraying mechanism (7) and an inclined heavy wax oil collecting tank (8) in order from bottom to top. The liquid spraying direction of the liquid spraying mechanism (4) is toward the bottom of the fractionation tower (1). Both ends of the vertical tube (5) are blocked. A plurality of gas outlet holes are evenly processed on the side wall of the vertical tube (5). The lower end of the vertical tube (5) is connected to an air inlet pipe (9) extending to the outside of the fractionation tower (1). The fractionation tower around the vertical tube (5) (1) A spiral half-tube (10) is provided on the side wall, and a plurality of liquid outlet holes are processed on the spiral half-tube (10); the wax oil extraction pipe (11) of the heavy wax oil collecting tank (8) is connected to the hot medium inlet of the heat exchanger (2); the hot medium outlet of the heat exchanger (2) is connected to the liquid inlet of the liquid spraying mechanism (4); the outlet of the raw oil tank (3) is connected to the cold medium inlet of the heat exchanger (2); and the cold medium outlet of the heat exchanger (2) is connected to the liquid inlet of the spraying mechanism (7) and the spiral half-tube (10), respectively.
2. A coking fractionation system capable of preventing and controlling coking according to claim 1, characterized in that A semi-annular pipe (13) is coaxially arranged on the outer side of the fractionating tower (1), and the outer side of the semi-annular pipe (13) is connected to the wax oil extraction pipe (11) through a pipeline. A plurality of nozzles (14) are evenly spaced on the inner side of the semi-annular pipe (13), and the nozzles (14) are connected to the fractionating tower (1) above the bottom plate of the heavy wax oil collecting tank (8), and the spraying direction of the nozzles (14) is toward the lower end of the heavy wax oil collecting tank (8).
3. A coking fractionation system capable of preventing and controlling coking according to claim 1, characterized in that A jacket (15) is provided on the outer wall of the distillation tower (1) below the vertical cylinder (5).
4. A coking fractionation system capable of preventing and controlling coking according to claim 3, characterized in that The jacket (15) is divided into two independent chambers by a partition (16); the outlet and the inlet of the jacket (15) are respectively arranged on the two chambers; a plurality of heat exchange tubes (17) are arranged between the two chambers; and the heat exchange tubes (17) are located in the distillation tower (1).
5. A coking fractionation system capable of preventing and controlling coking according to claim 1, characterized in that A gas-liquid mixer (18) is arranged outside the fractionation tower (1), the liquid inlet of the gas-liquid mixer (18) is connected to the heat medium outlet of the heat exchanger (2), the gas inlet of the gas-liquid mixer (18) is connected to the steam pipeline (19), and the outlet of the gas-liquid mixer (18) is connected to the liquid spraying mechanism (4).
6. A coking fractionation system capable of preventing and controlling coking according to claim 1, characterized in that A filter (12) is provided on the wax oil extraction pipe (11) between the heavy wax oil collecting tank (8) and the heat medium inlet of the heat exchanger (2).
7. A coking fractionation system capable of preventing and controlling coking according to claim 1, characterized in that The outlet of the crude oil tank (3) is tangentially connected to the side wall of the fractionation tower (1) below the vertical cylinder (5) through a pipeline.