Ultrahigh-pressure low-temperature fluid pressurization system

Abstract

The invention provides an ultrahigh-pressure low-temperature fluid pressurization system which comprises a hydraulic driving mechanism, pressurization pieces and a heat insulation container, the number of the pressurization pieces is two or more, pressurization cavities are formed in the pressurization pieces, each pressurization cavity is provided with an input end for inputting fluid in a one-way mode and an output end for outputting fluid in a one-way mode, and plunger rods are connected to the pressurization pieces in a sealed mode; the plunger rods can slide inwards or outwards along the pressurizing cavities so as to reduce or increase the volume of the pressurizing cavities, low-temperature liquid is stored in the heat insulation container, the pressurizing cavities of the pressurizing part are all located in the heat insulation container and immersed by the low-temperature liquid, and the hydraulic driving mechanism is connected with the multiple plunger rods and can alternately drive the plunger rods to slide towards the interiors of the pressurizing cavities. Therefore, the fluid in each pressurizing cavity is pressurized alternately; the multiple pressurizing cavities are alternately driven to pressurize fluid, the capacity of continuous high-pressure liquid supply is achieved, compared with a traditional single-action pressurizing pump, pressure fluctuation caused by intermittent liquid outlet is remarkably reduced through the mode, the liquid discharging end of the system is prevented from being damaged, and the stability of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid pressurization, and in particular to an ultra-high pressure and low temperature fluid pressurization system. Background Art

[0002] Cryogenic liquid pumps are used to transport cryogenic liquids (such as liquid hydrogen, liquid oxygen, liquid nitrogen and liquefied natural gas, etc.) in the fields of petroleum, air separation and chemical industry. According to different working principles, cryogenic pumps are mainly divided into two types: reciprocating and centrifugal. Centrifugal pumps have no self-priming ability, simple structure, few moving parts, and high speed, but their boosting effect is small, and they are mostly used for low and medium pressure transportation. Reciprocating pumps are mostly piston pumps or plunger pumps. The existing reciprocating pumps are used in systems with high pressure and small flow. Unlike general-purpose booster pumps, cryogenic liquid pumps must maintain low temperature during liquid transportation and minimize cold loss, otherwise the cryogenic pump will not work due to liquid vaporization.

[0003] In order to increase the density of the transported liquid, or to use low-temperature and high-pressure fluids for corresponding cutting, surface treatment, etc., a supercharging treatment of an ultra-high-pressure cryogenic fluid boosting system is required. At present, high-pressure cryogenic pumps generally use a single-acting reciprocating structure to compress the cryogenic fluid in the boosting chamber, and the driving component is a crank connecting rod. In the field of ultra-high pressure applications, the requirements for the drive motor are high, the overall design structure is complex, the space occupied is large, the vibration is large, the pressure at the discharge end fluctuates greatly and is easy to damage. In addition, the start and stop action of the boosting pump is complex, and it cannot respond quickly when the pressure is maintained. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problems in the prior art that the pressure fluctuation of the discharge end is large and the discharge end is easily damaged.

[0005] In order to solve the above technical problems, the present invention provides an ultra-high pressure and low temperature fluid boosting system, which includes: a hydraulic drive mechanism, a boosting component and an insulating container, the boosting component has more than two boosting chambers each formed therein, the boosting chambers each having an input end for unidirectional fluid input and an output end for unidirectional fluid output, the boosting components are sealed with plunger rods, the plunger rods can slide inward or outward along the boosting chamber to reduce or increase the volume of the boosting chamber, the insulating container contains low temperature liquid, the boosting chambers of the boosting components are all located in the insulating container and immersed in the low temperature liquid, the hydraulic drive mechanism is connected to a plurality of plunger rods, and can alternately drive the plunger rods to slide into the boosting chambers, thereby alternately pressurizing the fluid in each boosting chamber.

[0006] Furthermore, the booster has two parts, and the hydraulic drive mechanism includes a cylinder body, which is connected to an external hydraulic source. A piston is slidably arranged in the cylinder body, and the piston is connected to the plunger rods of the two boosters. The external hydraulic source drives the piston to move back and forth, thereby alternately driving the plunger rod to slide into the booster chamber.

[0007] Furthermore, the hydraulic drive mechanism is a plurality of oil cylinders correspondingly connected to the plunger rods, which drive the oil cylinders to work alternately, thereby alternately driving the plunger rods to slide toward the inside of the boost chamber.

[0008] Furthermore, a channel for the plunger rod to enter is formed on the booster, and the channel is communicated with the boost chamber.

[0009] Furthermore, a stuffing seal is provided in the channel, and the stuffing seal is located between the plunger rod and the channel.

[0010] Furthermore, a support ring is arranged in the channel, the support ring supports the plunger rod, and the support ring is made of a material with the same or similar expansion coefficient as the plunger rod.

[0011] Furthermore, both ends of the cylinder body are fixedly sealed and connected to the booster, and a coaxial sealing ring is provided on one side of the channel close to the cylinder body to prevent the hydraulic oil from entering the booster chamber through the channel.

[0012] Furthermore, a subcooler immersed in cryogenic liquid is also provided in the insulation container, one end of the subcooler is connected in parallel with the input ends of the plurality of boosting chambers through pipelines, and the other end is connected with an external fluid source pipeline.

[0013] Furthermore, a liquid inlet regulating valve is provided between the subcooler and the input end of the boost chamber, and the liquid inlet regulating valve is used to discharge the fluid with a higher gas content from the system.

[0014] Furthermore, it also includes an accumulator, the input end of the accumulator is connected to the output end pipeline of the boosting chamber to reduce the pressure fluctuation of the high-pressure fluid discharged from the boosting chamber.

[0015] It can be seen from the above technical scheme that the beneficial effects of the present invention are: by alternately driving multiple booster chambers to pressurize the fluid, the ability of continuous high-pressure liquid supply is achieved. Compared with the traditional single-acting booster pump, this method significantly reduces the pressure fluctuations caused by intermittent liquid discharge, avoids damage to the system discharge end, and improves the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the ultra-high pressure and low temperature fluid pressurization system provided in this application.

[0017] The accompanying drawings are marked as follows: 1. Automatic refilling valve; 2. Liquid level gauge; 3. Insulated container; 4. Plunger rod; 5. Stuffing seal box; 6. Hydraulic oil outlet check valve; 7. Hydraulic oil inlet check valve; 8. Support ring; 9. Coaxial sealing ring; 10. Support ring; 11. YX-shaped sealing ring for hole; 12. Piston; 13. Liquid inlet regulating valve; 14. Liquid inlet check valve; 15. Liquid discharge check valve; 16. Booster chamber; 17. Subcooler; 18. Accumulator; 19. Cylinder body; 20. Booster. DETAILED DESCRIPTION

[0018] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0019] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0020] In order to further illustrate the principle and structure of the present invention, preferred embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0021] See also Figure 1 , an ultra-high pressure and low temperature fluid boosting system provided in this embodiment, includes a boosting component 20 and a hydraulic drive mechanism, the number of the boosting components 20 is more than two and a boosting chamber 16 is formed in each boosting component 20, the boosting chamber 16 has an input end for unidirectional input of fluid and an output end for unidirectional output of fluid, an external fluid source is connected to the input end pipeline, the hydraulic drive mechanism realizes fluid boosting by reducing the volume of the boosting chamber 16, when boosting the fluid, the hydraulic drive mechanism alternately drives multiple boosting chambers 16 to reduce, thereby realizing continuous output of the boosted liquid and reducing the pressure fluctuation caused by intermittent liquid discharge.

[0022] Specifically, the above-mentioned booster 20 is sealed with a plunger rod 4, and the plunger rod 4 is linked to the hydraulic drive mechanism. Driven by the hydraulic drive mechanism, the plunger rod 4 can slide inward or outward along the booster chamber 16. When sliding into the booster chamber 16, the volume of the booster chamber 16 can be reduced to pressurize the fluid, and the pressurized fluid flows outward through the output end of the unidirectional output fluid; when the plunger rod 4 slides outward, the volume of the booster chamber 16 is increased, and the external fluid enters the booster chamber 16 through the input end of the booster chamber 16.

[0023] During the pressurization process, the cryogenic liquid needs to be kept at a low temperature to avoid vaporization. Therefore, an insulating container 3 is also provided, in which the cryogenic liquid is stored, and a part of the supercharging member 20 is located in the insulating container 3, and in particular, the supercharging chamber 16 is located in the insulating container 3 and is immersed in the cryogenic liquid; the insulating container 3 can provide the necessary cooling capacity for other components in the system, such as the supercharging chamber 16, the subcooler 17 and the accumulator 18 described below, to ensure that the cryogenic fluid maintains its low temperature state during the entire supercharging process.

[0024] Furthermore, in one embodiment of the hydraulic drive mechanism, when there are two boosting components 20, the hydraulic drive mechanism includes a cylinder body 19, the cylinder body 19 is connected to an external hydraulic source, a piston 12 is slidably arranged in the cylinder body 19, the piston 12 is connected to the plunger rods 4 of the two boosting components 20, the cross-sectional area of ​​the piston 12 is usually 10-15 times the cross-sectional area of ​​the plunger rod 4, the external hydraulic source drives the piston 12 to move back and forth with the same pressure output, the piston 12 drives the plunger rod 4 to move back and forth, so that the plunger rod 4 on one side of the piston 12 moves into the boosting chamber 16, and the plunger rod 4 on the other side moves out of the boosting chamber 16, so as to realize alternately driving the plunger rod 4 to slide inside the boosting chamber 16, thereby realizing continuous output of the boosted liquid.

[0025] This embodiment adopts a liquid-driven double-acting booster structure, which boosts pressure through Pascal principle conversion. The liquid output per single stroke is large, which can effectively reduce the wear of moving parts and increase the service life of the booster pump.

[0026] Furthermore, a three-position four-way electro-hydraulic reversing valve (not shown) is provided between the external hydraulic source and the cylinder body 20, and the inlet and outlet of the hydraulic oil are controlled by the external three-position four-way electro-hydraulic reversing valve.

[0027] The shape of the insulated container 3 in this embodiment is a concave shape, forming two protrusions protruding upward, and two boosters 20 are respectively arranged on the two protrusions, and the two boosters 20 are symmetrical to each other. The cylinder body 19 is arranged between the two boosters 20, and the two ends of the cylinder body 19 are sealed and fixedly connected to the boosters 20. The two boosters 20 support the cylinder body 19. Such a design improves the integration of the entire system and reduces the floor space required for the system.

[0028] Furthermore, a channel for the plunger rod 4 to enter is formed on the booster 20, and the channel is connected to the boost chamber 16. A stuffing box 5 is arranged between the channel and the plunger rod 4. The stuffing box 5 is used to seal the gap between the plunger rod 4 and the channel to prevent the low-temperature and high-pressure fluid in the boost chamber 16 from leaking into the external environment. The stuffing box 5 also has a certain elasticity and wear resistance, can adapt to the movement of the plunger rod 4 and maintain the sealing effect.

[0029] Furthermore, a support ring 10 is provided in the channel to support the plunger rod 4. The main function of the support ring 10 is to enhance the structural stability of the plunger rod 4 during the supercharging process. Since the plunger rod 4 needs to withstand greater pressure and axial force during supercharging, if there is not enough support, the plunger rod 4 may shake or deform when subjected to pressure, thus affecting the supercharging effect. The presence of the support ring 10 can effectively prevent this from happening, ensuring that the plunger rod 4 can still maintain linear motion under high pressure; and the support ring 10 is made of a material with the same or similar expansion coefficient as the plunger rod 4. Selecting materials with the same or similar expansion coefficients can ensure that the deformation of the two is similar under working conditions, so that the support ring 10 can also enhance the structural stability under low temperature conditions.

[0030] Furthermore, it also includes a coaxial sealing ring 9 arranged between the channel and the plunger rod 4. The coaxial sealing ring 9 is arranged on the side of the channel close to the cylinder body 19. The coaxial sealing ring 9 ensures the sealing between the oil cylinder and the cylinder, prevents mixing or leakage between the hydraulic oil and the low-temperature fluid, and ensures the normal operation of the booster system.

[0031] Furthermore, as another embodiment of the hydraulic drive mechanism, the hydraulic drive mechanism is a cylinder whose number corresponds to the plunger rod 4, and the cylinders are all driven by an external hydraulic source. The output end of the cylinder is connected to the plunger rod 4. When boosting, the operator can alternately drive the cylinders to work, thereby alternately driving the plunger rod 4 to slide into the boosting chamber 16. Compared with the embodiment of the hydraulic drive mechanism described above, this embodiment requires the setting of multiple cylinders connected to the plunger rod 4. Although the cost is higher, similar technical effects can also be achieved.

[0032] Furthermore, a subcooler 17 is also included. The subcooler 17 is arranged in the insulated container 3 and immersed in the cryogenic liquid. One end of the subcooler 17 is connected in parallel with the input ends of the multiple pressurization chambers 16 through a pipeline, and the other end is connected to an external fluid source pipeline. The subcooler 17 can be an existing heat exchanger. The present application is preferably a spiral tube heat exchanger. The fluid needs to flow through the subcooler 17 before entering the pressurization chamber 16. Under the action of the subcooler 17, the cryogenic liquid in the insulated container 3 exchanges heat with the fluid, and the fluid is precooled; in the process of the cryogenic fluid being pressurized, due to the increase in pressure and the rise in temperature, part of the liquid will be vaporized. By pre-supercooling the fluid, its vaporization rate during the pressurization process can be reduced, and the impact of the gas generated by the vaporization on the system can be reduced.

[0033] Furthermore, a liquid inlet regulating valve 13 is provided between the subcooler 17 and the input end of the boosting chamber 16. At the initial start-up of the boosting system, the gas content of the liquid in the cryogenic fluid pipeline is relatively high. At this time, opening the liquid inlet regulating valve 13 can discharge the liquid with a relatively high gas content from the system to reduce problems caused by gasification during the subsequent boosting process, such as pressure fluctuations or damage to the pump body.

[0034] Furthermore, it also includes an accumulator 18, the input end of the accumulator 18 is connected to the output end pipeline of the boosting chamber 16, and the supercharged ultra-high pressure fluid enters the accumulator 18 through the liquid outlet end of the boosting chamber 16. The main function of the accumulator 18 is to reduce the pressure fluctuation of the high pressure medium discharged from the boosting chamber 16. In addition, in order to further reduce the gas content of the high pressure and low temperature fluid and take away part of the compression heat of the compression process, the accumulator 18 is also placed in the insulating container 3 and immersed in the low temperature liquid.

[0035] In order to realize one-way input at the input end of the boosting chamber 16 and one-way output at the output end, it also includes an inlet one-way valve 14 and a discharge one-way valve 15. The inlet one-way valve 14 is arranged between the input end of each boosting chamber 16 and the subcooler 17, and the discharge one-way valve 15 is arranged at the outlet of the output end of each boosting chamber 16, thereby realizing one-way input and one-way output of fluid in the boosting chamber 16.

[0036] Furthermore, the insulating container 3 is a semi-open low-temperature container, which can realize the saturated temperature supply of the low-temperature liquid under atmospheric pressure, and provide cooling capacity for the accumulator 18, the supercooler 17 and the boost chamber 16. The insulating container 3 is also provided with a liquid level gauge 2 and an automatic liquid replenishing valve 1. The automatic liquid replenishing valve 1 is connected to the external low-temperature liquid source pipeline. The liquid level gauge 2 can monitor the liquid level of the low-temperature liquid in the insulating container 3 and automatically replenish the liquid through the automatic liquid replenishing valve 1.

[0037] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. An ultra-high pressure and low temperature fluid pressurization system, characterized in that: It includes a hydraulic drive mechanism, a booster and an insulating container; the booster has more than two booster chambers formed inside, each of which has an input end for unidirectional fluid input and an output end for unidirectional fluid output, and the booster is sealed with a plunger rod, which can slide inward or outward along the booster chamber to reduce or increase the volume of the booster chamber; the insulating container contains cryogenic liquid, and the booster chambers of the booster are located in the insulating container and immersed in the cryogenic liquid; the hydraulic drive mechanism is connected to multiple plunger rods, and can alternately drive the plunger rods to slide into the booster chamber, thereby alternately pressurizing the fluid in each booster chamber.

2. The ultra-high pressure and cryogenic fluid pressurization system according to claim 1, characterized in that: There are two boosting parts, and the hydraulic drive mechanism includes a cylinder body, which is connected to an external hydraulic source. A piston is slidably arranged in the cylinder body, and the piston is connected to the plunger rods of the two boosting parts. The external hydraulic source drives the piston to move back and forth, thereby alternately driving the plunger rod to slide into the boosting chamber.

3. The ultra-high pressure and cryogenic fluid pressurization system according to claim 1, characterized in that: The hydraulic drive mechanism is a plurality of oil cylinders correspondingly connected to the plunger rods, which drive the oil cylinders to work alternately, thereby alternately driving the plunger rods to slide toward the inside of the boosting chamber.

4. The ultra-high pressure and cryogenic fluid pressurization system according to claim 2, characterized in that: The booster is formed with a channel for the plunger rod to enter, and the channel is communicated with the booster chamber.

5. The ultra-high pressure and cryogenic fluid pressurization system according to claim 4, characterized in that: A stuffing seal box is arranged in the channel, and the stuffing seal box is located between the plunger rod and the channel.

6. The ultra-high pressure and cryogenic fluid pressurization system according to claim 4, characterized in that: A support ring is arranged in the channel to support the plunger rod. The support ring is made of a material having the same or similar expansion coefficient as that of the plunger rod.

7. The ultra-high pressure and cryogenic fluid pressurization system according to claim 4, characterized in that: Both ends of the cylinder body are fixedly and sealedly connected to the booster, and a coaxial sealing ring is arranged on one side of the channel close to the cylinder body to prevent the hydraulic oil from entering the booster chamber through the channel.

8. The ultra-high pressure and cryogenic fluid pressurization system according to claim 1, characterized in that: A subcooler immersed in low-temperature liquid is also arranged in the insulation container. One end of the subcooler is connected in parallel with the input ends of the multiple boosting chambers through pipelines, and the other end is connected to an external fluid source pipeline.

9. The ultra-high pressure and cryogenic fluid pressurization system according to claim 8, characterized in that: A liquid inlet regulating valve is also provided between the subcooler and the input end of the boost chamber, and the liquid inlet regulating valve is used to discharge the fluid with a higher gas content out of the system.

10. The ultra-high pressure and cryogenic fluid pressurization system according to claim 1, characterized in that: It also includes an accumulator, the input end of the accumulator is connected to the output end pipeline of the boosting chamber to reduce the pressure fluctuation of the high-pressure fluid discharged from the boosting chamber.

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