Device and method for receiving liquid ammonia and oil in sequential conveying main pipeline
By setting up a gas-liquid separation device and a high-pressure return pipeline in the sequential conveying device of liquid ammonia and oil, the separate storage of liquid ammonia and oil products is solved, and the pressure energy waste and evaporation loss caused by the discontinuous concentration distribution caused by the liquid ammonia-oil mixed liquid is solved, and the pressure energy waste and evaporation loss caused by the high inlet pressure is achieved, and safe and efficient reception and storage of liquid ammonia and oil products are achieved.
Patent Information
- Application Number
- CN202510204646.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-24
- Publication Date
- 2025-05-27
AI Technical Summary
During the sequential transportation of liquid ammonia and oil products, there is a liquid ammonia-oil mixture in the pipeline, resulting in discontinuous concentration distribution. It is possible that the oil products carry liquid ammonia into the oil storage tank or the liquid ammonia carries oil into the liquid ammonia storage tank, and the downstream station needs to maintain a high inlet pressure to receive liquid ammonia, resulting in waste of pressure energy and evaporation of oil products.
Design a device, including a liquid ammonia storage tank and an oil storage tank, and realize the separate storage of liquid ammonia and oil by setting up a gas-liquid separation device and a high-pressure return pipeline. The gas-liquid separation device is used to separate the liquid ammonia components in the oil product, the high-pressure reflow pipeline is used to reflow liquid ammonia, and the oil discharge pipeline is used to reflow the oil in the liquid ammonia storage tank to the oil product storage tank.
It effectively avoids rapid gasification of liquid ammonia and evaporation loss caused by a large amount of liquid ammonia entering the oil storage tank, reduces the waste of pressure energy caused by throttling the pipe medium, and ensures the safety of oil storage tanks.
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Figure CN120043047A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of fuel transportation, and in particular to a device and method for sequentially injecting liquid ammonia and oil products into a transportation pipeline. Background Art
[0002] Disclosing the information of this background art section is only intended to increase the understanding of the overall background of the present invention, and is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.
[0003] As an extension of the hydrogen industry, liquid ammonia is considered a new type of low-carbon fuel. As a fuel, liquid ammonia can be transported with extremely high efficiency through existing oil pipeline facilities. The normal boiling point of liquid ammonia is -33.5°C. With the help of low-temperature atmospheric storage tanks, large-scale storage can be achieved under conditions below -33.5°C. Refined oil products such as gasoline and diesel obtained by refineries are usually stored at normal temperature and pressure, and the storage temperature is 0 - 50°C. Sequential transportation (also known as alternate transportation) refers to the alternate transportation of two or more media in the same section of transportation pipeline in a set order, and can be applied to the transportation of liquid ammonia and oil products in existing oil pipeline facilities. After being transported through the sequential transportation pipeline, the temperature of liquid ammonia will be close to the ambient temperature around the pipeline, significantly higher than its own normal boiling point. Therefore, a high pressure needs to be maintained in the pipeline to maintain the liquid phase. However, when the downstream station receives liquid ammonia and oil products from the sequential transportation pipeline, the following problems need to be faced:
[0004] (1) There is a liquid ammonia-oil product mixture in the main sequential transportation pipeline. Due to the poor mutual solubility and density difference between the two, when there are obvious elevation fluctuations in the pipeline, the oil products may deposit in the low-lying areas, and the liquid ammonia may accumulate at the high points, resulting in a discontinuous change in the concentration distribution of the mixed liquid section. Therefore, even when it is not the time period for the mixed liquid interface to arrive at the station, there may be a situation where the oil products carry liquid ammonia into the oil product storage tank or the liquid ammonia carries oil products into the liquid ammonia storage tank due to the pipeline residue at any time.
[0005] (2) The liquid ammonia storage tanks at downstream stations are generally normal temperature and high-pressure storage tanks, and the design pressure of the storage tanks is not less than 2.033 MPa. When the station receives liquid ammonia, the inlet pressure of the main sequential transportation pipeline needs to be maintained at a relatively high level to enable the liquid ammonia to smoothly enter the normal temperature and high-pressure storage tank; however, the oil product storage tanks are generally atmospheric storage tanks, and the required inlet pressure of the oil product transportation pipeline is about 0.2 MPa. If the inlet pressure is controlled above the ammonia saturated vapor pressure to avoid the gasification of liquid ammonia, throttling and pressure reduction of the pipeline transportation medium are required before receiving, which will cause waste of pressure energy and evaporation loss of oil products during the process, and the rapid gasification of the mixed liquid ammonia entering the oil product storage tank will also threaten the safety of the oil product storage tank. Summary of the Invention
[0006] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a device and method for receiving liquid ammonia and oil products in a sequential transportation main pipeline. By setting up a gas-liquid separation device, a large amount of liquid ammonia is prevented from entering the oil product storage tank. By setting up an oil product discharge pipeline and a high-pressure reflux pipeline connecting the oil product storage tank and the liquid ammonia storage tank, the separate storage of liquid ammonia and oil products during the receiving stage is realized.
[0007] To achieve the above object, the present invention is realized through the following technical solutions:
[0008] In the first aspect, a device for receiving liquid ammonia and oil products in a sequential transportation main pipeline includes a liquid ammonia storage tank and an oil product storage tank. The liquid ammonia storage tank and the oil product storage tank are respectively connected to the sequential transportation main pipeline. A first pressure reducing valve and a gas-liquid separation device are arranged upstream of the oil product storage tank. The gas-liquid separation device and the oil product storage tank are respectively connected to a gas discharge pipeline. The gas discharge pipeline is connected to a high-pressure reflux pipeline through a pressurizing device, and the high-pressure reflux pipeline is connected to the liquid ammonia storage tank;
[0009] The liquid ammonia storage tank is connected to the oil product storage tank through an oil product discharge pipeline, and a second pressure reducing valve is arranged on the oil product discharge pipeline.
[0010] In the second aspect, a method for receiving liquid ammonia and oil products in a sequential transportation main pipeline based on the above device for receiving liquid ammonia and oil products in a sequential transportation main pipeline includes the following processes:
[0011] S1. When liquid ammonia is in front and oil products are behind in the sequential transportation main pipeline and enter the station yard, the liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank; the oil-rich mixed liquid section and the oil products in the liquid ammonia-oil product mixed liquid are depressurized by the first pressure reducing valve and separated by the gas-liquid separation device. The liquid phase enters the oil product storage tank, and the gas phase enters the gas discharge pipeline and enters the liquid ammonia storage tank after being pressurized by the pressurizing device;
[0012] S2. When oil products are in front and liquid ammonia is behind in the sequential transportation main pipeline and enter the station yard, the oil products and the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid are depressurized by the first pressure reducing valve and separated by the gas-liquid separation device. The liquid phase enters the oil product storage tank; the ammonia-rich mixed liquid section and the liquid ammonia in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank;
[0013] S3. When the oil product liquid level in the liquid ammonia storage tank is higher than the set value, the oil product in the liquid ammonia storage tank is depressurized by the second pressure reducing valve and then transported to the oil product storage tank through the oil product discharge pipeline.
[0014] The beneficial effects of the present invention are as follows:
[0015] 1. The present invention fully considers inevitable situations such as "cutting the interface between oil products and liquid ammonia" during the sequential transportation of liquid ammonia and oil products, or "irregular entry of oil products deposited at the bottom of the pipeline carried by the liquid ammonia section into the station due to changes in the pipeline operation conditions". The oil products in the liquid ammonia storage tank are returned to the oil product storage tank through the oil product discharge pipeline; by setting up a gas separation device and a gas discharge pipeline, it is possible to avoid the rapid gasification of liquid ammonia caused by a large amount of liquid ammonia entering the oil product storage tank, the increase in oil product evaporation loss, and possible tank damage.
[0016] 2. When receiving oil products into the station, the inlet pressure of the sequential transportation main pipeline is higher than the saturated vapor pressure of the oil products, and it is possible to allow the inlet pressure to be lower than the saturated vapor pressure of ammonia, thereby reducing the waste of pressure energy caused by the throttling of the pipeline transportation medium, and further avoiding problems such as the increase in the temperature of the oil products and the increase in evaporation loss caused by throttling. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The schematic diagrams in the specification that form a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.
[0018] The distances or dimensions between each part are exaggerated in the figures for showing the positions of each part, and the schematic diagrams are only for illustrative purposes.
[0019] Figure 1 It is a schematic structural diagram of the device for receiving liquid ammonia and oil products in the sequential transportation main pipeline in Embodiment 1.
[0020] Among them, 1. Sequential transportation main pipeline; 2. Liquid ammonia sub - transportation point; 3. Oil product sub - transportation point; 4. First valve; 5. Second valve; 6. Oil product receiving pipeline; 7. Liquid ammonia receiving pipeline; 8. First pressure reducing valve; 9. Gas - liquid separation device; 10. Oil product storage tank; 11. Gas discharge pipeline; 12. Liquid ammonia storage tank; 13. Pressure relief pipeline; 14. Third valve; 15. High - pressure return pipeline; 16. Fourth valve; 17. Liquid ammonia discharge pipeline; 18. Fifth valve; 19. Oil product discharge pipeline; 20. Booster equipment; 21. Sixth valve; 22. Seventh valve; 23. Low - pressure vent pipeline; 24. Second pressure reducing valve. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] The present invention will be further described below in conjunction with the drawings and embodiments.
[0022] A device for receiving liquid ammonia and oil products in a sequential transportation main pipeline includes: a liquid ammonia storage tank and an oil product storage tank. The liquid ammonia storage tank and the oil product storage tank are respectively connected to the sequential transportation main pipeline. A first pressure reducing valve and a gas - liquid separation device are arranged upstream of the oil product storage tank. The gas - liquid separation device and the oil product storage tank are respectively connected to a gas discharge pipeline. The gas discharge pipeline is connected to a high - pressure return pipeline through booster equipment, and the high - pressure return pipeline is connected to the liquid ammonia storage tank;
[0023] The liquid ammonia storage tank is connected to the oil product storage tank through an oil product discharge pipeline, and a second pressure reducing valve is provided on the oil product discharge pipeline for reducing the pressure of the normal temperature and high-pressure oil product output from the liquid ammonia storage tank to normal pressure.
[0024] In the above settings, the ammonia component mixed in the oil product is mainly separated by a gas-liquid separation device, and then is transported back to the liquid ammonia storage tank through a gas discharge pipeline and a high-pressure reflux pipeline. The ammonia component is separated upstream of the oil product storage tank to avoid problems such as increased evaporation loss of the oil product and sudden pressure increase caused by a large amount of gaseous ammonia input from the bottom of the oil product storage tank; the oil product mixed in the liquid ammonia is transported back to the oil product storage tank through the oil product discharge pipeline in the liquid ammonia storage tank, so as to realize the smooth reception of liquid ammonia and oil product in the sequential transportation main pipeline.
[0025] Optionally, the gas discharge pipeline is connected to a low-pressure vent pipeline. When the amount of gas phase escaping from the gas-liquid separation device and the oil product storage tank is small, it is not economical to reflux to the liquid ammonia storage tank through a pressurization device, and then it can be discharged through the low-pressure vent pipeline.
[0026] Optionally, the oil product storage tank is an atmospheric pressure oil product storage tank, and the liquid ammonia storage tank is a high-pressure normal temperature liquid ammonia storage tank. Since the temperatures of the liquid ammonia and the oil product in the sequential transportation main pipeline will tend to be consistent with the pipeline environment and are in a normal temperature state when reaching the receiving station, it is a conventional equipment for the downstream station to select an atmospheric pressure oil product storage tank and a high-pressure normal temperature liquid ammonia storage tank.
[0027] Optionally, the liquid ammonia storage tank is connected to the sequential transportation main pipeline through a liquid ammonia receiving pipeline for transporting liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil product mixed liquid. The oil product storage tank is connected to the sequential transportation main pipeline through an oil product receiving pipeline for transporting oil product and the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid. A first pressure reducing valve and a gas-liquid separation device are sequentially arranged on the oil product receiving pipeline for separating liquid ammonia before it enters the oil product storage tank; since the two types of liquids are transported separately, when transporting the medium mainly composed of oil product, the pressure in the transportation main pipeline can be adjusted without continuously maintaining it above the ammonia saturated vapor pressure, thereby avoiding waste of pressure energy and evaporation loss of the oil product.
[0028] Optionally, on the sequential transportation main pipeline, the branch point of the liquid ammonia receiving pipeline is arranged upstream of the oil product receiving pipeline to ensure that when the liquid ammonia receiving pipeline is closed, the liquid ammonia in the blind end of the liquid ammonia receiving pipeline on the sequential transportation main pipeline can be carried by the oil product to the downstream and enter the oil product storage tank; if the branch point of the liquid ammonia receiving pipeline is arranged downstream of the oil product receiving pipeline, a blind end is formed between the oil product branch point and the liquid ammonia branch valve. The residual liquid ammonia in this blind end is not easily carried by the oil product to the oil product receiving pipeline. If the inlet pressure during oil product reception drops below the ammonia saturated vapor pressure, the liquid ammonia in this blind end will be gasified, causing pipeline pressure fluctuations or even damage.
[0029] Optionally, the liquid ammonia storage tank is connected to a pressure relief pipeline. When the pressure in the liquid ammonia storage tank exceeds its design pressure, the gas is discharged from the pressure relief pipeline to maintain the safe pressure of the container.
[0030] A method for receiving and transporting liquid ammonia and oil products in the main pipeline based on the above device for receiving and transporting liquid ammonia and oil products in the main pipeline according to the receiving sequence includes the following processes:
[0031] S1. When liquid ammonia enters the station first and oil products enter the station later in the batch transportation main pipeline, the liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank; the oil-rich mixed liquid section and the oil products in the liquid ammonia-oil product mixed liquid are depressurized by a first pressure reducing valve, and after gas-liquid separation by a gas-liquid separation device, the liquid phase enters the oil product storage tank, and the gas phase enters the gas discharge pipeline and enters the liquid ammonia storage tank after being pressurized by a pressurizing device;
[0032] S2. When oil products enter the station first and liquid ammonia enters the station later in the batch transportation main pipeline, the oil products and the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid are depressurized by a first pressure reducing valve, and after gas-liquid separation, the liquid phase enters the oil product storage tank; the ammonia-rich mixed liquid section and the liquid ammonia in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank;
[0033] S3. When the oil product liquid level in the liquid ammonia storage tank is higher than the set value, the oil products in the liquid ammonia storage tank are depressurized by a second pressure reducing valve and then transported to the oil product storage tank through the oil product discharge pipeline.
[0034] In the above process, when receiving oil products into the station, the inlet pressure of the batch transportation main pipeline is higher than the saturated vapor pressure of the oil products, and it is allowed that the inlet pressure is lower than the saturated vapor pressure of ammonia, thereby reducing the waste of pressure energy caused by throttling of the pipeline transportation medium, and further avoiding problems such as the increase in the temperature of the oil products and the increase in evaporation loss caused by throttling. When transporting oil products, if no obvious gas phase precipitates in the gas-liquid separation device, the inlet pressure can be controlled above the saturated vapor pressure of the oil products, and the pressure reducing valve is fully opened (without pressure reduction) to achieve safe and efficient transportation.
[0035] Optionally, when the liquid ammonia storage tank is connected to the batch transportation main pipeline, the inlet pressure of the batch transportation main pipeline is adjusted to be higher than the pressure in the liquid ammonia storage tank so that the medium in the batch transportation main pipeline can enter the liquid ammonia storage tank for storage.
[0036] Optionally, during the process of the main pipeline switching from entering the liquid ammonia storage tank to entering the oil product storage tank, the inlet pressure of the main pipeline is switched from the pressure when connected to the liquid ammonia storage tank to above the saturated vapor pressure of ammonia corresponding to the inlet temperature.
[0037] Optionally, if the gas escape amount in the gas-liquid separation device is small, adjust the inlet pressure of the main pipeline to be higher than the saturated vapor pressure of the oil product and lower than the saturated vapor pressure of ammonia; if the gas escape amount is large, maintain the inlet pressure of the main pipeline above the saturated vapor pressure of ammonia corresponding to the inlet temperature.
[0038] Optionally, when the gas escape amount from the gas-liquid separation device and the oil product storage tank is small, the economy of returning to the liquid ammonia storage tank through the booster equipment is not high, so the gas phase is discharged through the low-pressure vent pipeline.
[0039] Example 1
[0040] A device for receiving liquid ammonia and oil products in a sequential transportation main pipeline, comprising: a liquid ammonia storage tank 12 and an oil product storage tank 10. The oil product storage tank 10 is an atmospheric pressure oil product storage tank, and the liquid ammonia storage tank 12 is a high-pressure normal temperature liquid ammonia storage tank; the liquid ammonia storage tank 12 and the oil product storage tank 10 are respectively connected to the sequential transportation main pipeline 1. The liquid ammonia storage tank 12 and the sequential transportation main pipeline 1 are connected through a liquid ammonia receiving pipeline 7 for transporting liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil product mixed liquid. The oil product storage tank 10 and the sequential transportation main pipeline 1 are connected through an oil product receiving pipeline 6 for transporting oil products and the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid. A first pressure reducing valve 8 and a gas-liquid separation device 9 are sequentially arranged on the oil product receiving pipeline 6 to separate liquid ammonia before it enters the oil product storage tank; due to the sequential transportation of the two types of liquids, when transporting the medium mainly composed of oil products, the pressure in the sequential transportation main pipeline 1 can be adjusted without continuously maintaining it above the saturated vapor pressure of ammonia, thereby avoiding waste of pressure energy and evaporation loss of oil products.
[0041] On the sequential transportation main pipeline 1, the liquid ammonia sub-transfer point 2 of the liquid ammonia receiving pipeline 7 is arranged upstream of the oil product sub-transfer point 3 of the oil product receiving pipeline 6 to ensure that when the liquid ammonia receiving pipeline 7 is closed, the liquid ammonia in the blind end of the liquid ammonia sub-transfer point 2 on the sequential transportation main pipeline 1 can be carried by the oil product to the downstream and enter the oil product receiving pipeline.
[0042] A second valve 5 is arranged on the liquid ammonia receiving pipeline 7 to control its on-off; a first valve 4 is arranged between the first pressure reducing valve 8 and the oil product sub-transfer point 3 on the oil product receiving pipeline 6 to control its on-off; both the first valve 4 and the second valve 5 are close to the sequential transportation main pipeline 1 to make the blind end generated when the valve is closed as short as possible.
[0043] The gas-liquid separation device 9 and the oil product storage tank are respectively connected to a gas discharge pipeline 11. The gas discharge pipeline 11 is connected to a high-pressure return pipeline 15 through a booster device 20, and the high-pressure return pipeline 15 is connected to the liquid ammonia storage tank 12; a sixth valve 21 is arranged upstream of the booster device of the gas discharge pipeline 11 to control the on-off of the pipeline between the gas separation device and the liquid ammonia storage tank 12.
[0044] The liquid ammonia storage tank 12 is connected to the oil storage tank 10 through the oil discharge pipeline 19. A second pressure reducing valve 24 is provided on the oil discharge pipeline 19 to reduce the pressure of the oil discharged from the liquid ammonia storage tank 12 to atmospheric pressure and transport it to the oil storage tank 10. Upstream of the second pressure reducing valve, a fifth valve 18 is provided near the liquid ammonia storage tank to control the on-off of the oil discharge pipeline 19.
[0045] The gas discharge pipeline 11 is connected to the low-pressure vent pipeline 23 upstream of the sixth valve 21. A small amount of gas phase in the gas discharge pipeline 11 can be discharged through the low-pressure vent pipeline 23. A seventh valve 22 is provided on the low-pressure vent pipeline 23 to control the on-off of the low-pressure vent pipeline 23.
[0046] The liquid ammonia storage tank 12 is connected to the pressure relief pipeline 13. When the pressure in the liquid ammonia storage tank 12 exceeds its design pressure, the gas is discharged from the pressure relief pipeline 13 to maintain the safe pressure of the container. A third valve 14 is provided on the pressure relief pipeline 13 to control its on-off.
[0047] At a position of the liquid ammonia storage tank 12 higher than the interface of the oil discharge pipeline 19, a liquid ammonia discharge pipeline 17 is provided. A fourth valve 16 is provided on the liquid ammonia discharge pipeline 17 to control the on-off of the liquid ammonia discharge pipeline 17 to transport liquid ammonia fuel to the outside.
[0048] A method for receiving and transporting liquid ammonia and oil in the main pipeline based on the above device for receiving and transporting liquid ammonia and oil in the main pipeline according to the receiving order, includes the following process:
[0049] S1. When liquid ammonia enters the station first and oil enters later in the batch transportation main pipeline 1, open the second valve 5 and close the first valve 4, so that the liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil mixed liquid enter the liquid ammonia receiving pipeline 7 and enter the liquid ammonia storage tank 12; when the ammonia concentration in the mixed liquid section decreases to the cut-off concentration set by the process, first open the first valve 4 and then close the second valve 5. The oil-rich mixed liquid section and the oil in the liquid ammonia-oil mixed liquid enter the oil receiving pipeline 6. After being depressurized by the first pressure reducing valve 8 and gas-liquid separated by the gas-liquid separation device 9, the liquid phase (i.e., oil) enters the oil storage tank 10, and the gas phase (i.e., ammonia gas) enters the gas discharge pipeline 11, enters the booster equipment 20 through the opened sixth valve 21, is boosted to a pressure higher than the internal pressure of the liquid ammonia storage tank 12, and then enters the liquid ammonia storage tank 12 through the high-pressure return pipeline 15;
[0050] S2. When the oil product in the sequential transportation main pipeline 1 enters the station yard before the liquid ammonia, open the first valve 4 and close the second valve 5, so that the rich oil mixed liquid section in the oil product and the liquid ammonia-oil product mixed liquid enters the oil product receiving pipeline 6. After being depressurized by the first pressure reducing valve 8 and separated by the gas-liquid separation device, the liquid phase enters the oil product storage tank; when the liquid ammonia concentration in the mixed liquid section rises to the cutting concentration set by the process, first open the second valve 5 and then close the first valve 4, so that the rich ammonia mixed liquid section and the liquid ammonia in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank 12 through the liquid ammonia receiving pipeline 7;
[0051] S3. When the oil product liquid level in the liquid ammonia storage tank 12 is higher than the set value, open the fifth valve 18, so that the oil product in the liquid ammonia storage tank 12 enters the oil product discharge pipeline 19. After the oil product is depressurized by the second pressure reducing valve 24, it is transported to the oil product storage tank 10.
[0052] When the liquid ammonia storage tank 12 is connected to the sequential transportation main pipeline 1, the staff adjusts the inlet pressure of the sequential transportation main pipeline 1 through the pressure regulating equipment of the sequential transportation main pipeline, making it higher than the pressure in the liquid ammonia storage tank 12, so that the medium in the sequential transportation main pipeline 1 can enter the liquid ammonia storage tank 12 for storage.
[0053] During the process of the sequential transportation main pipeline 1 switching from entering the liquid ammonia storage tank 12 to entering the oil product storage tank 10, the inlet pressure of the sequential transportation main pipeline 1 can be switched from the pressure when connected to the liquid ammonia storage tank 12 to the ammonia saturation vapor pressure corresponding to the inlet temperature; then adjust according to the gas evolution situation in the gas-liquid separation device 9: if the gas evolution amount is small, the inlet pressure of the sequential transportation main pipeline 1 can be adjusted to be higher than the oil product saturation vapor pressure and lower than the ammonia saturation vapor pressure to reduce the evaporation loss of the oil product and reduce the waste of pressure energy. At this time, the economy of flowing back to the liquid ammonia storage tank 12 through the booster equipment 20 is not high, so close the sixth valve 21 and open the seventh valve 22 to discharge the gas phase through the low-pressure vent pipeline 23; if the gas evolution amount is large, the inlet pressure of the sequential transportation main pipeline 1 should be maintained above the ammonia saturation vapor pressure corresponding to the inlet temperature to avoid a large amount of liquid ammonia gasification in the main pipeline 1.
[0054] When transporting the oil product, if there is no obvious gas phase precipitation in the gas-liquid separation device 9, the inlet pressure can be controlled above the oil product saturation vapor pressure, and the first pressure reducing valve 8 is fully opened (without pressure reduction) to achieve safe and efficient transportation.
[0055] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A device for receiving liquid ammonia and oil products in a sequentially transported main pipeline, characterized in that: It includes a liquid ammonia storage tank and an oil storage tank, the liquid ammonia storage tank and the oil storage tank are respectively connected to a sequential delivery main pipeline, a first pressure reducing valve and a gas-liquid separation device are arranged upstream of the oil storage tank, the gas-liquid separation device and the oil storage tank are respectively connected to a gas discharge pipeline, the gas discharge pipeline is connected to a high-pressure reflux pipeline through a booster device, and the high-pressure reflux pipeline is connected to the liquid ammonia storage tank; The liquid ammonia storage tank is connected to the oil storage tank through an oil discharge pipeline, and a second pressure reducing valve is arranged on the oil discharge pipeline.
2. The device for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 1, characterized in that: The gas discharge pipeline is connected to the low-pressure venting pipeline.
3. The device for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 1, characterized in that: The oil storage tank is a normal pressure oil storage tank, and the liquid ammonia storage tank is a high pressure normal temperature liquid ammonia storage tank.
4. The device for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 1, characterized in that: The liquid ammonia storage tank is connected to the sequential transportation main pipeline through a liquid ammonia receiving pipeline; the oil storage tank is connected to the sequential transportation main pipeline through an oil receiving pipeline, and a first pressure reducing valve and a gas-liquid separation device are sequentially arranged on the oil receiving pipeline.
5. The device for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 4 is characterized in that: On the sequential transport main pipeline, the distribution point of the liquid ammonia receiving pipeline is arranged upstream of the oil product receiving pipeline.
6. The device for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 1, characterized in that: The liquid ammonia storage tank is connected to a pressure relief pipeline.
7. A method for sequentially conveying liquid ammonia and oil products in a main pipeline based on the device for sequentially conveying liquid ammonia and oil products in a main pipeline according to any one of claims 1 to 6, characterized in that: The process includes: S1. When liquid ammonia enters the station first and oil products enter the station later in the sequential transportation main pipeline, the liquid ammonia and the ammonia-rich mixed liquid section in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank, the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid and the oil product are depressurized by the first pressure reducing valve, and after gas-liquid separation by the gas-liquid separation device, the liquid phase enters the oil product storage tank, and the gas phase enters the gas discharge pipeline, and enters the liquid ammonia storage tank after being pressurized by the booster equipment; S2, when the oil product enters the station first and the liquid ammonia enters the station later in the sequential transportation main pipeline, the oil product and the oil-rich mixed liquid section in the liquid ammonia-oil product mixed liquid are depressurized by the first pressure reducing valve, and after gas-liquid separation, the liquid phase enters the oil product storage tank; the ammonia-rich mixed liquid section and liquid ammonia in the liquid ammonia-oil product mixed liquid enter the liquid ammonia storage tank; S3. When the oil level in the liquid ammonia storage tank is higher than the set level, the oil in the liquid ammonia storage tank is decompressed by the second pressure reducing valve and then transported to the oil storage tank through the oil discharge pipeline.
8. The method for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 7, characterized in that: When the liquid ammonia storage tank is connected to the sequential transportation main pipeline, the inlet pressure of the sequential transportation main pipeline is adjusted to be higher than the pipeline pressure in the liquid ammonia storage tank.
9. The method for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 8, characterized in that: When the main pipeline switches from entering the liquid ammonia storage tank to entering the oil storage tank, the inlet pressure of the main pipeline switches from the pressure when it is connected to the liquid ammonia storage tank to the ammonia saturated vapor corresponding to the inlet temperature; Alternatively, if the amount of gas escaping from the gas-liquid separation device is small, the inlet pressure of the main pipeline is adjusted to be higher than the saturated vapor pressure of the oil product but lower than the saturated vapor pressure of ammonia; if the amount of gas escaping is large, the inlet pressure of the main pipeline is maintained above the saturated vapor pressure of ammonia corresponding to the inlet temperature.
10. The method for receiving liquid ammonia and oil products in a sequentially transported main pipeline according to claim 8, characterized in that: The gas phase is discharged through a low-pressure vent line.