Isothermal turboexpander

Abstract

The present invention discloses an isothermal turbine expander, comprising an expander housing, wherein the bottom of one end of the expander housing is connected to an air inlet nozzle communicating with the inside of the expander housing, and the other end of the expander housing is connected to an air outlet pipe communicating with the inside of the expander housing; both ends of the expander housing are connected to connecting flanges; the inner sides of both ends of the expander housing are connected to sealed bearings, a main shaft is rotatably connected between the two sealed bearings, the two ends of the main shaft respectively penetrate the corresponding sealed bearings, a plurality of blades are circumferentially connected on the main shaft, and cavities are arranged on the inner sides of both ends of the main shaft. The blades of the present invention are hollow and form a gas circulation channel together with the main shaft. The blades are both gas expansion work devices and used as heat exchangers, that is, gas expansion work and heat exchange are carried out simultaneously, isothermal expansion is achieved, and energy conversion efficiency is higher.

Description

Technical Field

[0001] The invention relates to the technical field of turbine expanders, and in particular to an isothermal turbine expander. Background Art

[0002] The turbo expander is a key component required for obtaining cold energy and compressed air energy storage systems in air separation equipment and natural gas liquefaction separation equipment. It is the heart that ensures the stable operation of the entire equipment.

[0003] The main principle is to use a certain pressure of gas to expand adiabatically in the turbine expander, and then do work to consume the internal energy of the gas itself, so that the gas itself is cooled to achieve the purpose of refrigeration;

[0004] Fig. 9 The existing turbine expander has the following disadvantages: since the existing turbine expander adopts adiabatic expansion, there is no heat exchange with the outside during the expansion process, and the efficiency of converting the internal energy of the gas into kinetic energy is relatively low. If a higher conversion efficiency is to be obtained, a multi-stage expander is required, and a heat exchanger needs to be installed at the same time. The system is relatively complex and the cost is higher. Summary of the invention

[0005] In order to overcome the above technical problems, the object of the present invention is to provide an isothermal turbine expander.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] An isothermal turbine expander comprises an expander casing, wherein an air inlet nozzle communicating with the interior of the expander casing is connected to the bottom of one end of the expander casing, and an air outlet pipe communicating with the interior of the expander casing is connected to the other end of the expander casing; connecting pieces are arranged at both ends of the expander casing; a main shaft passes through the expander casing, and the main shaft is rotatably connected to the expander casing, a plurality of blades are circumferentially connected to the main shaft, cavities are arranged on the inner sides of both ends of the main shaft, an air inlet communicating with the corresponding cavity is opened at one end of the main shaft close to the air outlet pipe, an air outlet communicating with the corresponding cavity is opened at one end of the main shaft close to the air inlet nozzle, each of the blades is a hollow body, and a plurality of connecting air ports communicating with the corresponding blades are opened circumferentially on the side wall of the cavity.

[0008] As a further solution of the present invention: the blades are made of alloy material and have a spiral structure.

[0009] As a further solution of the present invention: sealed bearings are connected to the inner sides of both ends of the expander casing, the main shaft is rotatably connected between the two sealed bearings, and both ends of the main shaft pass through corresponding sealed bearings respectively.

[0010] Beneficial effects of the present invention:

[0011] 1. The blades of the present invention are hollow and together with the main shaft form a channel for gas circulation. The blades are both gas expansion work devices and heat exchangers. That is, gas expansion work and heat exchange are carried out simultaneously, achieving isothermal expansion and higher energy conversion efficiency.

[0012] 2. The present invention can be applied in different fields and scenarios in conjunction with different components. It is flexible to use and has a simple structure, small size and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below in conjunction with the accompanying drawings.

[0014] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0015] Figure 2 It is a schematic diagram of the structure of the connection between the blade and the main shaft in the present invention;

[0016] Figure 3 It is a schematic diagram of the overall cross-sectional structure of the present invention;

[0017] Figure 4 It is a schematic diagram of the local structure of the blade in the present invention;

[0018] Figure 5 It is a schematic diagram of the overall cross-sectional structure of the first embodiment of the present invention;

[0019] Figure 6 is a schematic diagram of the three-dimensional structure of the second embodiment of the present invention;

[0020] Figure 7 This is a schematic diagram of the structure of the main shaft and the fan blades in the second embodiment of the present invention;

[0021] Figure 8 is a schematic diagram of the overall cross-sectional structure of Embodiment 3 of the present invention;

[0022] Fig. 9 It is a schematic diagram of the structure of an existing turbo expander.

[0023] In the figure: 1. air inlet nozzle; 2. blades; 3. air outlet pipe; 4. fan blades; 5. air inlet; 6. main shaft; 7. air outlet; 8. expander casing; 9. sealed bearing; 10. cavity; 11. connector; 12. connecting air port; 13. air guide cover; 14. air compressor; 15. first connecting duct; 16. engine; 17. second connecting duct; 18. return air pipe; 19. air inlet pipe; 20. machine body; 21. linkage shaft; 22. impeller; 23. heat exchanger; 24. air guide pipe; 25. coupling; 26. permanent magnet generator; 27. connecting air pipe. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] like Fig. 9 As shown, the existing turbine expander includes a body 20, and the internal rotation of the body 20 is connected to a linkage shaft 21, one end of the linkage shaft 21 is connected to an impeller 22, and the end of the body 20 close to the impeller 22 is connected to an intake pipe 19, the port of the intake pipe 19 is aligned with the impeller 22, and the intake pipe 19 is used to connect a device that conducts high-pressure gas so that the high-pressure gas acts on the impeller 22, and then the impeller 22 drives the linkage shaft 21 to rotate, one end of the body 20 close to the impeller 22 is the intake end, and the other end is the outlet end, and the body 20 is also connected to a heat exchanger 23. The existing turbine expander adopts an adiabatic expansion method, and the internal energy of the high-pressure gas is converted into kinetic energy. At the same time, heat energy is exchanged by relying on the heat exchanger 23 to obtain low-temperature gas.

[0026] like Figure 1-Figure 4 As shown, an isothermal turbine expander comprises an expander casing 8, an air inlet nozzle 1 communicating with the inside of the expander casing 8 is fixedly connected to the bottom of one end of the expander casing 8, and a connecting thread is provided on the outer wall of the air inlet nozzle 1, which is convenient for docking with the connecting pipe end of the relevant air inlet equipment; an air outlet pipe 3 communicating with the inside of the expander casing 8 is fixedly connected to the top of the other end of the expander casing 8, and the air outlet pipe 3 is convenient for the gas entering the expander casing 8 to be discharged; both ends of the expander casing 8 are provided with connecting members 11, and the connecting members 11 are selected according to the equipment structure to be connected to the two ends of the expander casing 8, and a main shaft 6 runs through the expander casing 8; sealed bearings 9 are fixedly installed on the inner sides of the two ends of the expander casing 8, and the main shaft 6 is rotatably connected to the two The two ends of the main shaft 6 respectively penetrate the corresponding sealed bearings 9 between the sealed bearings 9, so that the main shaft 6 is rotatably connected to the expander housing 8. The inner sides of both ends of the main shaft 6 are provided with cavities 10. The outer wall of one end of the main shaft 6 close to the outlet pipe 3 is provided with a plurality of air inlets 5 connected to the corresponding cavities 10 in a circumferential direction. The outer wall of one end of the main shaft 6 close to the air inlet nozzle 1 is provided with a plurality of air outlets 7 connected to the corresponding cavities 10 in a circumferential direction. The main shaft 6 is connected with a plurality of blades 2 in a circumferential direction. Each blade 2 is a hollow body. The blade 2 is an alloy material body that is convenient for heat conduction, and can be specifically an alloy material such as aluminum alloy or copper alloy, and has a spiral structure; a plurality of connecting air ports 12 connected to the corresponding blades 2 are provided in a circumferential direction on the side wall of the cavity 10;

[0027] High-pressure gas A enters the expander casing 8 from the air inlet nozzle 1 and disperses, and the airflow acts on the blades 2, so that the blades 2 rotate through the main shaft 6. In this process, part of the internal energy of the high-pressure gas is converted into kinetic energy. At the same time, gas B enters the corresponding cavity 10 from the air inlet 5 at one end of the main shaft 6, and then enters each hollow blade 2 from the connecting air port 12 in the corresponding cavity 10. During the flow of gas B, since its temperature is higher than that of the gas in the expander casing 8, heat exchange occurs between the two, that is, the gas B entering the blade 2 releases heat and cools down, and the high-pressure gas A dispersed outside the blade 2 absorbs heat and heats up, realizing isothermal expansion, and then the high-pressure gas A dispersed in the expander casing 8 is discharged from the outlet pipe 3, and the cooled gas B in the blade 2 enters the corresponding cavity 10 from the connecting air port 12 at the other end of the main shaft 6, and is finally discharged from the outlet 7, realizing efficient conversion of the internal energy of the high-pressure gas A. Specific embodiment 1

[0029] like Figure 5 As shown, the connecting member 11 is a connecting flange, and the end of the expander housing 8 near the air outlet pipe 3 is connected to the air guide pipe 24 through the connecting flange. This embodiment is used in conjunction with the engine 16, and the end of the air guide pipe 24 is connected to the air outlet end of the engine 16. A connecting air pipe 27 is connected between the air outlet pipe 3 and the air inlet end of the engine 16. The air inlet nozzle 1 is connected to the equipped high-pressure air storage tank, and the end of the main shaft 6 near the air inlet nozzle 1 is connected to the coupling 25. A permanent magnet generator 26 of model NE-200 is also provided on the main shaft 6, and the end of the main shaft 6 near the air inlet nozzle 1 is connected to the rotating shaft end of the permanent magnet generator 26 through the coupling 25;

[0030] The working principle of this embodiment is as follows: the exhaust gas during the operation of the engine 16 first enters one end of the main shaft 6, and then enters each hollow blade 2, and the high-pressure gas in the high-pressure gas storage tank enters the expander housing 8 from the air inlet nozzle 1, and then the two airflows exchange heat energy through the hollow blades 2, and at the same time, the gas in the expander housing 8 is discharged from the air outlet pipe 3, and then enters the engine 16 through the connecting air pipe 27, and is mixed with the fuel in the engine 16 and burned to do work, and because the main shaft 6 can be connected to the corresponding rotating shaft end of the permanent magnet generator 26 through the coupling 25, when the main shaft 6 rotates under the action of the air flow, the permanent magnet generator 26 is driven to operate and generate electricity, thereby converting kinetic energy into electrical energy. This embodiment can reduce the temperature of the exhaust gas from the engine 16, and at the same time make full use of the gas internal energy at the air inlet end of the engine 16.

[0031] The engine 16 can be replaced by a gas turbine or a steam turbine, both of which can be effectively implemented. Specific embodiment 2

[0033] like Figure 6-Figure 7As shown, what is different from the specific embodiment one is that the air duct 24 and the engine 16 in the specific embodiment one are replaced by an air duct cover 13 and fan blades 4, the end of the expansion machine casing 8 close to the air outlet pipe 3 is connected to the air duct cover 13 through a connecting flange, the end of the main shaft 6 close to the air outlet pipe 3 is in the air duct cover 13, and the end of the main shaft 6 in the air duct cover 13 is circumferentially connected with a plurality of fan blades 4, and the fan blades 4 are installed in a manner of exhausting air in the direction of the air inlet 5.

[0034] The working principle of this embodiment is as follows: high-pressure gas enters the expander casing 8 from the air inlet nozzle 1, and when it acts on the blades 2, the blades 2 drive the main shaft 6 to rotate due to the push of the airflow, and the main shaft 6 drives the fan blades 4 to rotate, and the fan blades 4 drive the airflow in the surrounding environment to flow into the air guide hood 13, and then enters the cavity 10 through the air inlet 5 at the end of the main shaft 6, and then enters the blades 2, and finally realizes heat exchange with the gas in the expander casing 8. This embodiment can be used for temperature regulation in air-conditioning equipment. When used, the air inlet nozzle 1 is connected to the compressor of the air-conditioning equipment, and the air-conditioning compressor compresses the high-pressure gas into the air inlet nozzle 1. Specific embodiment three

[0036] like Figure 8 As shown, different from the specific embodiment 1, the air guide pipe 24 and the engine 16 in the specific embodiment 1 are replaced by the first connecting conduit 15 and the air compressor 14, the first connecting conduit 15 is connected to the end of the expander housing 8 close to the outlet pipe 3 through the connecting flange, the air compressor 14 is connected to the first connecting conduit 15, and one end of the air compressor 14 is the outlet end and connected to the first connecting conduit 15, and the other end is the inlet end, and the model of the air compressor 14 is BK15-8;

[0037] The coupling 25 in the first specific embodiment is removed, and then the second connecting conduit 17 is connected to the end of the expander housing 8 close to the coupling 25 through a connecting flange, and a return air pipe 18 is connected between the second connecting conduit 17 and the air intake nozzle 1. The return air pipe 18 and the second connecting conduit 17 are both steel pipes and are integrally cast;

[0038] The working principle of this embodiment is as follows: the air compressor 14 compresses the corresponding gas into high-pressure gas, and passes through the first connecting duct 15 to the air inlet 5, then enters the cavity 10 at the end of the main shaft 6, and then enters each blade 2, exchanges heat with the gas in the expander casing 8, reduces the temperature of the gas in the expander casing 8, and then the gas discharged from the blade 2 flows to the air inlet nozzle 1 through the second connecting duct 17 and the return pipe 18, and then acts on the blade 2, so that the blade 2 rotates through the main shaft 6, which facilitates the low-temperature gas in the expander casing 8 to be discharged from the outlet pipe 3.

[0039] From the above three embodiments, it can be known that the turbine expander of the present invention can be used in combination with different accessories according to different application scenarios.

[0040] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. An isothermal turbine expander, comprising an expander housing (8), one end of the expander housing (8) being connected to an air inlet nozzle (1) communicating with the interior of the expander housing (8), and the other end of the expander housing (8) being connected to an air outlet pipe (3) communicating with the interior of the expander housing (8); both ends of the expander housing (8) being provided with connecting pieces (11); a main shaft (6) passing through the expander housing (8), and the main shaft (6) being rotatably connected to the expander housing (8), and a plurality of blades (2) being circumferentially connected to the main shaft (6), characterized in that: A cavity (10) is provided on the inner side of both ends of the main shaft (6); an air inlet (5) communicating with the corresponding cavity (10) is provided at one end of the main shaft (6) close to the air outlet pipe (3); an air outlet (7) communicating with the corresponding cavity (10) is provided at one end of the main shaft (6) close to the air inlet nozzle (1); each blade (2) is a hollow body; and a plurality of connecting air ports (12) communicating with the corresponding blades (2) are provided on the circumferential side of the side wall of the cavity (10); The blade (2) is a spiral structure; The expander housing (8) is connected to a second connecting conduit (17), and a return pipe (18) is connected between the second connecting conduit (17) and the air intake nozzle (1). Gas exhausted from the blades (2) flows to the air intake nozzle (1) through the second connecting conduit (17) and the return pipe (18).

2. The isothermal turbo expander according to claim 1, characterized in that: The blade (2) is made of alloy material.

3. The isothermal turbo expander according to claim 1, characterized in that: Sealed bearings (9) are connected to the inner sides of both ends of the expander housing (8), the main shaft (6) is rotatably connected between the two sealed bearings (9), and both ends of the main shaft (6) respectively penetrate the corresponding sealed bearings (9).

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