A medium- and high-temperature solar steam generation device

Abstract

A medium- and high-temperature solar steam generation device. In this device, a metal tube with an endothermic coating on the outside is used as the heat-absorbing tube, and the heat-absorbing tube is welded to the cylinder body by welding; it is filled with a working fluid composed of more than two kinds of mutually soluble working fluids with different boiling points. The working fluid has the characteristics of high boiling point, low pressure, and good thermal conductivity; a rectification device is provided at the upper part of the cylinder body. After rectification, the steam with a low boiling point and good heat conduction effect enters the heat exchanger to heat the water in the steam drum, generating medium- and high-temperature steam and completing the steam generation process. A heat insulation layer is provided outside the cylinder body, which is connected to the concentrator heat-insulating glass sleeve through a sealing ring. The heat-insulating glass sleeve is placed on the outer periphery of the heat-collecting tube to complete the heat insulation process; the concentrator heat-insulating glass sleeve is a transparent structure with a Fresnel lens inside, which plays the role of heat insulation and light concentration. This device has the advantages of low system pressure, good airtightness, pressure resistance and safety, and high heat exchange efficiency, and can be widely used in areas and occasions with rich solar energy.

Description

Technical Field

[0001] The present invention relates to a solar steam generation device, in particular to a solar medium and high temperature steam generation device. Background Art

[0002] Solar energy is a clean energy source that is pollution-free, inexhaustible, and renewable. With the increasing maturity of solar thermal technology, the development and utilization of solar energy have been integrated into people's production and life. In particular, solar water heaters have developed rapidly and have obvious energy-saving effects. With the gradual saturation of the market and people's demand for high-grade heat sources, the research on solar steam generation devices has also received increasing attention.

[0003] For solar steam generation devices, especially in the field of medium and high temperature steam generation, most of them use large-scale array parabolic or dish-shaped mirrors to collect solar heat energy. The equipment is heavy, the process is troublesome, it is not resistant to typhoons, and its applicability to small devices is not high.

[0004] For the steam generation device with vacuum tube heat collection, in order to cope with the steam pressure, a sealing method is adopted at the pipe orifice. This kind of steam generation device with this sealing method has certain safety hazards, and scale will be generated after the hot water boils, seriously affecting the heat exchange effect and service life of the heat collection tube. Summary of the Invention

[0005] The present invention is to overcome the deficiencies of the prior art and provide a solar medium and high temperature steam generation device. This device uses a metal material tube with an external heat-absorbing coating and convenient for welding as the heat-absorbing tube, and the heat-absorbing tube is welded to the cylinder body by welding to solve the problems of poor pressure resistance and poor sealing of the device; it is filled with two or more working fluids with different boiling points and mutual solubility, and the working fluids have the characteristics of high boiling point, low pressure, and good thermal conductivity, to solve the problems of high internal pressure and potential safety hazards of the device; a rectification device is provided at the upper part of the cylinder body. After rectification, the steam with a low boiling point and good heat conduction effect enters the heat exchanger to heat the water in the steam drum to generate medium and high temperature steam.

[0006] The technical solution of the present invention is as follows:

[0007] A medium and high temperature solar steam generation device, comprising a heat collecting tube, an endothermic coating, a concentrating and heat-insulating glass sleeve, a sealing ring, a working medium liquid, a heat-insulating layer, a cylinder body, a rectifying device, a heat exchanger, and a steam drum. The heat collecting tube is integrally connected to the cylinder body and the rectifying device by welding, is in a vacuum state under normal pressure, and is filled with a glycerol solution working medium liquid inside. The rectifying device is located at the upper part of the cylinder body. There is an endothermic coating outside the heat collecting tube. During operation, the endothermic coating absorbs solar heat and transfers it to the working medium liquid in the heat collecting tube. The working medium liquid boils when heated under low pressure, generating mixed steam. After being rectified by the rectifying device, the steam with a low boiling point and good heat conduction effect enters the heat exchanger and exchanges heat with the water in the steam drum. The water in the steam drum boils when heated, generating medium and high temperature steam, thus completing the working process. The steam drum is connected to a safety valve, a steam outlet, a water replenishing valve, a blowdown valve, etc., and is provided with a heat exchanger inside. During operation, water enters the steam drum through the water replenishing valve, is heated and boiled by the heat exchanger inside to generate water steam, and the steam is discharged from the steam outlet, thus completing the steam generation process. The outside of the cylinder body is provided with a heat-insulating layer, and the heat-insulating layer is connected to the concentrating and heat-insulating glass sleeve through a sealing ring, thus completing the heat insulation process of the heat collecting device. The concentrating and heat-insulating glass sleeve is a transparent structure and is composed of an outer wall of the glass sleeve, an inner wall of the glass sleeve, and a Fresnel lens. The Fresnel lens is placed between the outer wall and the inner wall of the glass sleeve, thus completing the solar concentrating process. The heat-insulating glass sleeve is placed around the heat collecting tube, thus completing the heat insulation process of the heat collecting tube.

[0008] The heat collecting tube, the cylinder body, and the rectifying device are of an integrated structure and are in a vacuum state at normal temperature. The number of heat collecting tubes is determined by the required steam volume. The rectifying device is located at the upper part of the cylinder body.

[0009] The rectifying device is composed of multiple trays and an outer cylindrical body. The trays are perpendicular to the axis of the outer cylindrical body and are arranged parallel and staggeredly at a certain interval along the axis. The outer periphery of the trays is in close contact with the inner wall of the outer cylindrical body.

[0010] The cylinder body is connected to a vacuum pump and a process valve. The vacuum pump is turned on when necessary to remove excess impurity gases in the cylinder body.

[0011] The heat collecting tube is made of a metal material that is convenient for welding and is coated with an endothermic coating on the outside.

[0012] The working medium liquid is composed of two or more substances with different boiling points and is mutually soluble, and is a binary solution or a ternary solution. Among them, the one with a high boiling point is used as the main working medium liquid, and the one with a low boiling point and good heat conduction is used as the steam liquid. The working medium liquid has the characteristics of a high boiling point, a low pressure, and good heat conductivity.

[0013] The steam drum is a detachable steam drum.

[0014] Compared with the prior art, the present invention has the following remarkable effects:

[0015] (1) The system pressure is low. As can be seen from the above technical solution: The working fluid inside the device has the characteristics of high boiling point, low pressure, and good thermal conductivity. Compared with water vapor, it has a lower pressure at the same temperature, so the internal pressure of the system is low.

[0016] (2) Good sealing, more pressure-resistant, and safer. The heat collecting tube, the cylinder body, and the rectifying device are integrated by welding. Compared with the sealing method of the pipe orifice, the sealing performance is higher and it is more pressure-resistant; The heat absorbing tube of this device is a metal material tube with an external heat absorbing coating and is easy to weld, which is more pressure-resistant than a vacuum glass heat collecting tube and has high safety performance.

[0017] (3) High heat exchange efficiency. The inside of this device is in a vacuum state under normal pressure. When the working fluid is heated, it boils under low pressure, and the steam enters the heat exchanger to heat the water in the steam drum, generating medium and high temperature steam. The whole process utilizes the heat of phase change and has good heat transfer effect; In addition, the working fluid inside this device generates mixed steam after being heated. After being rectified by the rectifying device, the steam with low boiling point and good heat conduction effect enters the heat exchanger for heat exchange and condensation. Compared with the heat exchange medium of general heat pipes, the heat conduction effect is better.

[0018] (4) No scale is formed inside the device. The working fluid inside the device is composed of two or more mutually soluble substances. It boils when heated in the heat collecting tube, and the steam condenses after entering the heat exchanger. The whole process operates in a sealed environment and no scale will be generated.

[0019] The present invention can be widely applied to regions and places rich in low-temperature heat sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the present invention;

[0021] Figure 2 is a schematic structural diagram inside the device of the present invention;

[0022] Figure 3 is a schematic structural diagram of the concentrating and heat-insulating glass sleeve of the present invention.

[0023] In the figure: 1. Heat collecting tube, 2. Heat absorbing coating, 3. Concentrating and heat-insulating glass sleeve, 4. Sealing ring, 5. Working fluid, 6. Heat-insulating layer, 7. Cylinder body, 8. Vacuum pump, 9. Rectifying device, 10. Heat exchanger, 11. Steam drum, 12. Safety valve, 13. Steam outlet, 14. Water replenishing valve, 15. Drain valve, 16. Process valve, 17. Outer wall of the glass sleeve, 18. Inner wall of the glass sleeve, 19. Fresnel lens. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be further elaborated in detail through the following embodiments. The following embodiments are based on the technical solution of the present invention, and give detailed implementation manners and specific processes. However, the protection scope of the present invention is not limited to the following embodiments. For those of ordinary skill in the art, any obvious changes made without departing from the technical solution of the present invention fall within the protection scope of the claims of the present invention.

[0025] A solar medium and high temperature steam generating device, such as Figure 1 , includes a heat collecting tube 1, a heat absorbing coating 2, a concentrating and heat insulating glass sleeve 3, a sealing ring 4, a working medium liquid 5, a heat insulating layer 6, a cylinder body 7, a rectifying device 9, a heat exchanger 10, and a steam drum 11; the heat collecting tube 1 is integrally connected with the cylinder body 7 and the rectifying device 9 by welding, and is in a vacuum state under normal pressure. The inside is filled with a glycerol solution working medium liquid 5, and the rectifying device 9 is located at the upper part of the cylinder body 7; there is a heat absorbing coating 2 outside the heat collecting tube 1. During operation, the heat absorbing coating 2 absorbs solar heat and transfers it to the working medium liquid 5 in the heat collecting tube 1. The working medium liquid 5 boils under low pressure and generates mixed steam. After being rectified by the rectifying device 9, the steam with a low boiling point and good heat conduction effect enters the heat exchanger 10 and exchanges heat with the water in the steam drum 11. The water in the steam drum 11 boils due to heat absorption and generates medium and high temperature steam, completing the working process; the steam drum 11 is connected to a safety valve 12, a steam outlet 13, a water replenishing valve 14, a blowdown valve 15, etc., and a heat exchanger 10 is provided inside. During operation, water enters the steam drum 11 through the water replenishing valve 14, is heated and boiled by the heat exchanger 10 inside to generate water steam, and is discharged from the steam drum 11 through the steam outlet 13, completing the steam generation process; a heat insulating layer 6 is provided outside the cylinder body 7, and the heat insulating layer 6 is connected to the concentrating and heat insulating glass sleeve 3 through a sealing ring 4, completing the heat insulation process of the heat collecting device; the concentrating and heat insulating glass sleeve 3 is a transparent structure and is composed of a glass sleeve outer wall 17, a glass sleeve inner wall 18, and a Fresnel lens 19. The Fresnel lens 19 is placed between the glass sleeve outer wall 17 and the glass sleeve inner wall 18, completing the solar concentrating process; the heat insulating glass sleeve 3 is placed around the heat collecting tube 1, completing the heat insulation process of the heat collecting tube 1.

[0026] The heat collecting tube 1, the cylinder body 7, and the rectifying device 9 are of an integrated structure and are in a vacuum state at normal temperature. The number of heat collecting tubes 1 is determined by the required steam volume, and the rectifying device 9 is located at the upper part of the cylinder body 7.

[0027] The rectifying device 9 is composed of multiple trays and an outer cylindrical body. The trays are perpendicular to the axis of the outer cylindrical body and are arranged parallel and staggeredly at a certain interval along the axial direction. The outer periphery of the trays is in close contact with the inner wall of the outer cylindrical body.

[0028] The cylinder body 7 is connected to a vacuum pump 8 and a process valve 16. The vacuum pump 8 is turned on when necessary to remove excess impurity gases in the cylinder body.

[0029] The heat collecting tube is made of a metal material that is easy to weld, and an endothermic coating 2 is applied on the outside.

[0030] The working medium liquid 5 is composed of two or more substances with different boiling points and is mutually soluble, and is a binary solution or a ternary solution. Among them, the one with a higher boiling point is used as the working medium liquid itself, and the one with a lower boiling point and good heat conduction is used as the steam liquid. The working medium liquid 5 has the characteristics of a high boiling point, a low pressure, and good heat conduction.

[0031] The steam drum 11 is a detachable steam drum, which is convenient for cleaning the heat exchange tubes in the steam drum, making it difficult for the heat exchange tubes to form scale, improving the heat exchange efficiency of the heat exchange tubes and facilitating maintenance.

Claims

1. A medium- and high-temperature solar steam generation device, comprising a heat collection tube (1), an endothermic coating (2), a concentrating and heat-insulating glass sleeve (3), a sealing ring (4), a working medium solution (5), a heat-insulating layer (6), a cylinder body (7), a rectifying device (9), a heat exchanger (10), and a steam drum (11), characterized in that: The heat collecting tube (1) is integrally connected to the cylinder body (7) and the rectifying device (9) by welding, and is in a vacuum state under normal pressure. A working medium solution (5) represented by a glycerol solution is filled inside. The rectifying device (9) is located at the upper part of the cylinder body (7). An endothermic coating (2) is provided outside the heat collecting tube (1). During operation, the endothermic coating (2) absorbs solar heat and transfers it to the working medium solution (5) in the heat collecting tube (1). The working medium solution (5) boils when heated under a low-pressure state, generating a mixed vapor. After being rectified by the rectifying device (9), the vapor with a low boiling point and good heat conduction effect enters the heat exchanger (10) and exchanges heat with the water in the steam drum (11). The water in the steam drum (11) boils when heated, generating medium- and high-temperature steam, thus completing the working process. The steam drum (11) is connected to a safety valve (12), a steam outlet (13), a water replenishing valve (14), and a blowdown valve (15), and a heat exchanger (10) is provided inside. During operation, water enters the steam drum (11) through the water replenishing valve (14), is heated and boiled by the heat exchanger (10) inside to generate water vapor, and the water vapor is discharged from the steam drum (11) through the steam outlet (13), thus completing the steam generation process. A heat preservation layer (6) is provided outside the cylinder body (7). The heat preservation layer (6) is connected to the concentrating heat preservation glass sleeve (3) through a sealing ring (4), thus completing the heat preservation process of the heat collection device. The concentrating heat preservation glass sleeve (3) is of a transparent structure and is composed of an outer wall of the glass sleeve (17), an inner wall of the glass sleeve (18), and a Fresnel lens (19). The Fresnel lens (19) is placed between the outer wall of the glass sleeve (17) and the inner wall of the glass sleeve (18), thus completing the solar concentrating process. The heat preservation glass sleeve (3) is placed on the outer periphery of the heat collecting tube (1), thus completing the heat preservation process of the heat collecting tube (1). The rectifying device (9) is composed of multiple trays and an outer cylindrical body. The trays are perpendicular to the axis of the outer cylindrical body and are arranged parallel and staggeredly at a certain interval along the axial direction. The outer periphery of the trays is in close contact with the inner wall of the outer cylindrical body. The heat collecting tube (1) is made of a metal material that is convenient for welding, and an endothermic coating (2) is applied outside. The working medium solution (5) is composed of two or more substances with different boiling points and is mutually soluble, and is a binary solution or a ternary solution. Among them, the substance with a high boiling point is used as the working medium main liquid, and the substance with a low boiling point and good heat conduction is used as the steam liquid. The working medium solution (5) has the characteristics of a high boiling point, a low pressure, and good heat conductivity.

2. The medium- and high-temperature solar steam generation device according to claim 1, characterized in that: The cylinder body (7) is connected to a vacuum pump (8) and a process valve (16).

3. The medium- and high-temperature solar steam generation device according to claim 1, characterized in that: The steam drum (11) is a detachable steam drum.

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