Ultrahigh-pressure low-temperature fluid pressurization system

Abstract

The utility model provides an ultrahigh pressure cryogenic fluid pressurization system which comprises a hydraulic driving mechanism, pressurization pieces and a heat insulation container, the number of the pressurization pieces is more than two, 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. 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 utility model relates to the technical field of fluid pressurization, and particularly relates 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, 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 categories: reciprocating pumps and centrifugal pumps. Centrifugal pumps have no self-priming ability, simple structures, few moving parts, and high rotational speeds, but their pressurization effect is relatively small and they are mostly used for low and medium pressure transportation. Reciprocating pumps are mostly piston pumps or plunger pumps, and the existing reciprocating pumps are used in systems with high pressure and small flow rates. Different from general universal pressurization pumps, cryogenic liquid pumps need to maintain low temperature during the liquid transportation process 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 perform corresponding cutting, surface treatment, etc. using cryogenic high-pressure fluids, pressurization treatment by an ultra-high pressure and low-temperature fluid pressurization system is required. Currently, high-pressure cryogenic pumps generally use a single-acting reciprocating structure to compress the cryogenic fluid in the pressurization chamber, and the driving component is a crank connecting rod. In the field of ultra-high pressure applications, the requirements for the driving motor are relatively high, the overall design structure is complex, the occupied space is large, the vibration is large, the pressure fluctuation at the liquid discharge end is large and it is easy to be damaged. In addition, the starting and stopping actions of the pressurization pump are complex and it cannot respond quickly under the requirement of pressure maintenance. Summary of the Utility Model

[0004] The purpose of the utility model is to solve the technical problem of large pressure fluctuation at the liquid discharge end and easy damage in the prior art.

[0005] To solve the above technical problem, the utility model provides an ultra-high pressure and low-temperature fluid pressurization system, which includes: a hydraulic driving mechanism, a pressurizing member, and an adiabatic container. The pressurizing member has two or more, and a pressurization chamber is formed inside each of them. Each pressurization chamber has an input end for unidirectionally inputting fluid and an output end for unidirectionally outputting fluid. A plunger rod is hermetically connected to each pressurizing member, and the plunger rod can slide inward or outward along the pressurization chamber to reduce or increase the volume of the pressurization chamber. A cryogenic liquid is stored in the adiabatic container, and the pressurization chambers of the pressurizing member are all located in the adiabatic container and are immersed in the cryogenic liquid. The hydraulic driving mechanism is connected to a plurality of plunger rods and can alternately drive the plunger rods to slide inward into the pressurization chamber, thereby alternately pressurizing the fluid in each pressurization chamber.

[0006] Further, the pressurizing member has two. The hydraulic driving mechanism includes a cylinder body, the cylinder body is connected to an external hydraulic source, a piston is slidably arranged inside the cylinder body, the piston is connected to the plunger rods of the two pressurizing members, and the external hydraulic source drives the piston to reciprocate, thereby alternately driving the plunger rods to slide inward into the pressurization chamber.

[0007] Furthermore, the hydraulic driving mechanism is a plurality of oil cylinders correspondingly connected to the plunger rod, and the oil cylinders are alternately driven to work, so as to alternately drive the plunger rod to slide into the pressurizing chamber.

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

[0009] Furthermore, a stuffing box seal is arranged in the channel, and the stuffing box 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 block are fixedly and sealedly connected to the pressurizing member, and a coaxial sealing ring is arranged on one side of the channel close to the cylinder block to prevent hydraulic oil from entering the pressurizing chamber through the channel.

[0012] Furthermore, a subcooler immersed in the cryogenic liquid is also arranged in the adiabatic container. One end of the subcooler is connected in parallel with the input ends of a plurality of pressurizing chambers through a pipeline, and the other end is connected to an external fluid source pipeline.

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

[0014] Furthermore, an accumulator is also included. The input end of the accumulator is connected to the output end of the pressurizing chamber through a pipeline to reduce the pressure fluctuation of the high-pressure fluid discharged from the pressurizing chamber.

[0015] As can be seen from the above technical solutions, the beneficial effects of the present utility model are as follows: By alternately driving a plurality of pressurizing 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 fluctuation caused by intermittent liquid discharge, avoids damage to the liquid discharge end of the system, and improves the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the ultra-high pressure cryogenic fluid boosting system provided by this application.

[0017] The description of the reference numerals is as follows: 1, automatic liquid filling valve; 2, liquid level gauge; 3, adiabatic container; 4, plunger rod; 5, stuffing box seal; 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 hole seal ring; 12, piston; 13, liquid inlet regulating valve; 14, liquid inlet check valve; 15, liquid discharge check valve; 16, pressurizing chamber; 17, subcooler; 18, accumulator; 19, cylinder block; 20, pressurizing member. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] Typical embodiments embodying the features and advantages of the present utility model will be described in detail in the following description. It should be understood that the present utility model can have various variations in different embodiments, all of which do not depart from the scope of the present utility model, and the descriptions and illustrations therein are essentially for illustrative purposes and not for limiting the present utility model.

[0019] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the 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 thus cannot be understood as a limitation to 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 specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

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

[0021] Please refer to Figure 1 , a super-high pressure and low-temperature fluid boosting system provided for this embodiment, includes a boosting member 20 and a hydraulic driving mechanism. The number of the boosting members 20 is two or more, and a boosting chamber 16 is formed in each of the boosting members 20. Each boosting chamber 16 has an input end for unidirectionally inputting fluid and an output end for unidirectionally outputting fluid. An external fluid source is connected to the input end through a pipeline. The hydraulic driving mechanism realizes the boosting of the fluid by reducing the volume of the boosting chamber 16. When boosting the fluid, the hydraulic driving mechanism alternately drives a plurality of boosting chambers 16 to shrink, realizing the continuous output of the boosted liquid and reducing the pressure fluctuation caused by intermittent liquid output.

[0022] Specifically, a plunger rod 4 is sealingly connected to the above-mentioned boosting member 20. The plunger rod 4 is linked to the hydraulic driving mechanism. Under the drive of the hydraulic driving mechanism, the plunger rod 4 can slide inward or outward along the boosting chamber 16. When sliding inward into the boosting chamber 16, the volume of the boosting chamber 16 can be reduced to boost the fluid, and the boosted fluid flows outwards through the output end for unidirectionally outputting fluid; when the plunger rod 4 slides outward, the volume of the boosting chamber 16 is increased, and the external fluid enters the boosting chamber 16 through the input end of the boosting chamber 16.

[0023] During the pressurization process, the cryogenic liquid needs to remain at a low temperature to avoid vaporization. Therefore, an adiabatic container 3 is also provided, and the cryogenic liquid is stored in the adiabatic container 3. A part of the pressurizing member 20 is located inside the adiabatic container 3. In particular, the pressurizing chamber 16 is located inside the adiabatic container 3 and is immersed in the cryogenic liquid. The adiabatic container 3 can provide the necessary cooling capacity for other components in the system, such as the pressurizing chamber 16, the subcooler 17 and the accumulator 18 described below, to ensure that the cryogenic fluid remains at its low temperature state throughout the pressurization process.

[0024] Furthermore, in an embodiment of the hydraulic drive mechanism, when there are two pressurizing members 20, the hydraulic drive mechanism includes a cylinder block 19, which is connected to an external hydraulic source. A piston 12 is slidably arranged inside the cylinder block 19. The piston 12 is connected to the plunger rods 4 of the two pressurizing members 20. The cross-sectional area of the piston 12 is usually 10-15 times that of the cross-section of the plunger rod 4. The external hydraulic source drives the piston 12 to reciprocate at the same pressure output. The piston 12 drives the plunger rods 4 to reciprocate, causing the plunger rod 4 on one side of the piston 12 to move into the pressurizing chamber 16 and the plunger rod 4 on the other side to move out of the pressurizing chamber 16, so as to alternately drive the plunger rod 4 to slide into the pressurizing chamber 16, thereby realizing the continuous output of the pressurized liquid.

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

[0026] Furthermore, a three-position four-way electro-hydraulic reversing valve (not shown in the figure) is also provided between the external hydraulic source and the cylinder block 20 to control the inlet and outlet of hydraulic oil through the external three-position four-way electro-hydraulic reversing valve.

[0027] In this embodiment, the shape of the adiabatic container 3 is concave, with two protruding parts protruding upward. The two pressurizing members 20 are respectively arranged on the two protruding parts and are symmetrical to each other. The cylinder block 19 is arranged between the two pressurizing members 20. The two ends of the cylinder block 19 are fixedly connected to the pressurizing members 20 in a sealed manner. The two pressurizing members 20 support the cylinder block 19. Such a design improves the integration of the entire system and reduces the floor area required by the system.

[0028] Furthermore, a channel for the plunger rod 4 to enter is formed on the pressurizing member 20. The channel is communicated with the pressurizing chamber 16. A packing seal 5 is arranged between the channel and the plunger rod 4. The packing seal 5 is used to seal the gap between the plunger rod 4 and the channel to prevent the leakage of the cryogenic high-pressure fluid in the pressurizing chamber 16 to the external environment. The packing seal 5 also has certain elasticity and wear resistance, and can adapt to the movement of the plunger rod 4 and maintain the sealing effect.

[0029] Further, a support ring 10 is arranged in the channel. The support ring 10 supports 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 pressurization process. Since the plunger rod 4 needs to bear a large pressure and axial force during pressurization, without sufficient support, the plunger rod 4 may vibrate or deform when bearing the pressure, which will affect the pressurization effect. The existence of the support ring 10 can effectively prevent this situation from occurring and ensure that the plunger rod 4 can still maintain linear motion under high pressure. Moreover, 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 their deformation amounts are similar under working conditions, so that the support ring 10 can also enhance the structural stability under low-temperature conditions.

[0030] Further, a coaxial sealing ring 9 is also included, which is 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 block 19. The coaxial sealing ring 9 ensures the sealing between the oil cylinder and the air cylinder, prevents the mixing or leakage between the hydraulic oil and the cryogenic fluid, and ensures the normal operation of the pressurization system.

[0031] Further, as another embodiment of the hydraulic driving mechanism, the hydraulic driving mechanism is an oil cylinder corresponding to the number of the plunger rods 4. The oil cylinders are all driven by an external hydraulic source. The output end of the oil cylinder is connected to the plunger rod 4. During pressurization, the operator can alternately drive the oil cylinders to work, so as to alternately drive the plunger rod 4 to slide into the pressurization chamber 16. Compared with the embodiment of the hydraulic driving mechanism described above, this embodiment requires multiple oil cylinders to be connected to the plunger rod 4. Although the cost is relatively high, similar technical effects can also be achieved.

[0032] Further, a subcooler 17 is also included. The subcooler 17 is arranged in the adiabatic container 3 and is immersed in the cryogenic liquid. One end of the subcooler 17 is connected in parallel with the input ends of 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. In this application, a spiral tube heat exchanger is preferably used. 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 adiabatic container 3 exchanges heat with the fluid, and the fluid is precooled. During the pressurization process of the cryogenic fluid, due to the increase in pressure and temperature, part of the liquid will vaporize. By pre-cooling the fluid in advance, the vaporization rate during the pressurization process can be reduced, and the influence of the gas generated by vaporization on the system can be reduced.

[0033] Further, a liquid inlet regulating valve 13 is also arranged between the subcooler 17 and the input end of the pressurization chamber 16. At the initial stage of starting the pressurization system, the gas content rate of the liquid in the cryogenic fluid pipeline is relatively high. At this time, opening the liquid inlet regulating valve 13 can discharge this part of the liquid with a high gas content rate from the system to reduce problems caused by vaporization during the subsequent pressurization process, such as pressure fluctuations or pump body damage.

[0034] Further, an accumulator 18 is further included. The input end of the accumulator 18 is connected to the output end of the pressurizing chamber 16 through a pipeline. The super-high-pressure fluid after pressurization enters the accumulator 18 through the liquid outlet end of the pressurizing chamber 16. The main function of the accumulator 18 is to reduce the pressure fluctuation of the high-pressure medium discharged from the pressurizing chamber 16. In addition, in order to further reduce the gas content rate of the high-pressure low-temperature fluid and take away part of the compression heat during the compression process, the accumulator 18 is also placed in the adiabatic container 3 and is immersed in the low-temperature liquid.

[0035] In order to achieve the one-way input at the input end and the one-way output at the output end of the pressurizing chamber 16, a liquid inlet check valve 14 and a liquid discharge check valve 15 are further included. The liquid inlet check valve 14 is arranged between the input end of each pressurizing chamber 16 and the subcooler 17, and the liquid discharge check valve 15 is arranged at the outlet of the output end of each pressurizing chamber 16, so as to achieve the one-way input and one-way output of the fluid in the pressurizing chamber 16.

[0036] Further, the adiabatic container 3 is a semi-open low-temperature container, which can supply the saturated temperature of the low-temperature liquid under atmospheric pressure, and provide cooling capacity for the accumulator 18, the subcooler 17 and the pressurizing chamber 16. A liquid level gauge 2 and an automatic liquid filling valve 1 are also arranged on the adiabatic container 3. The automatic liquid filling valve 1 is connected to an external low-temperature liquid source through a pipeline. The liquid level gauge 2 can monitor the liquid level of the low-temperature liquid in the adiabatic container 3 and automatically fill the liquid through the automatic liquid filling valve 1.

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

Claims

1. A super high pressure and low temperature fluid boosting system, characterized in that, It includes a hydraulic drive mechanism, a pressurizing member, and a heat-insulating container; the pressurizing member has more than two and each has a pressurizing chamber formed inside. Each pressurizing chamber has an input end for unidirectionally inputting fluid and an output end for unidirectionally outputting fluid. A plunger rod is hermetically connected to each pressurizing member, and the plunger rod can slide inward or outward along the pressurizing chamber to reduce or increase the volume of the pressurizing chamber; a cryogenic liquid is stored in the heat-insulating container, and the pressurizing chambers of the pressurizing member are all located inside the heat-insulating container and are immersed in the cryogenic liquid; the hydraulic drive mechanism is connected to multiple plunger rods and can alternately drive the plunger rods to slide inward into the pressurizing chamber, thereby alternately pressurizing the fluid in each pressurizing chamber.

2. The ultra-high pressure and low temperature fluid boosting system according to claim 1, wherein, The pressurizing member has two. The hydraulic drive mechanism includes a cylinder block, which is connected to an external hydraulic source. A piston is slidably arranged inside the cylinder block, and the piston is connected to the plunger rods of the two pressurizing members. The external hydraulic source drives the piston to reciprocate, thereby alternately driving the plunger rods to slide inward into the pressurizing chamber.

3. The ultra-high pressure and low temperature fluid boosting system according to claim 1, wherein The hydraulic drive mechanism is multiple oil cylinders correspondingly connected to the plunger rods, and the oil cylinders are alternately driven to work, thereby alternately driving the plunger rods to slide inward into the pressurizing chamber.

4. The ultra-high pressure and low temperature fluid boosting system according to claim 2, characterized in that, A channel for the plunger rod to enter is formed on the pressurizing member, and the channel communicates with the pressurizing chamber.

5. The ultra-high pressure and low temperature fluid boosting system according to claim 4, characterized in that, A stuffing box is arranged inside the channel, and the stuffing box is located between the plunger rod and the channel.

6. The ultra-high pressure and low temperature fluid boosting system according to claim 4, wherein A support ring is arranged inside the channel, and the support ring supports the plunger rod. The support ring is made of a material with the same or similar expansion coefficient as the plunger rod.

7. The ultra-high pressure and low temperature fluid boosting system according to claim 4, wherein Both ends of the cylinder block are fixedly and hermetically connected to the pressurizing member, and a coaxial sealing ring is arranged on one side of the channel close to the cylinder block to prevent hydraulic oil from entering the pressurizing chamber through the channel.

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

9. The ultra-high pressure and low temperature fluid boosting system according to claim 8, characterized in that, An inlet regulating valve is also arranged between the subcooler and the input end of the pressurizing chamber. The inlet regulating valve is used to discharge the fluid with a higher gas content rate from the system.

10. The ultra-high pressure and low temperature fluid boosting 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 of the pressurizing chamber through a pipeline to reduce the pressure fluctuation of the high-pressure fluid discharged from the pressurizing chamber.

Images