CN114811977A

CN114811977A - Solar particle heat absorber for magnetic non-contact transportation of magnetic particles

Info

Publication number: CN114811977A
Application number: CN202210183959.8A
Authority: CN
Inventors: 胡耀松; 颜健; 谢欣旖; 刘永祥; 田勇
Original assignee: Hunan University of Science and Technology
Current assignee: Chengdu Quanyi Network Technology Co ltd
Priority date: 2022-02-28
Filing date: 2022-02-28
Publication date: 2022-07-29
Anticipated expiration: 2042-02-28
Also published as: CN114811977B

Abstract

The invention discloses a solar energy particle heat absorber for magnetic non-contact transportation of magnetic particles, comprising magnetic solid particles, a conveying device, a particle thickness control valve for controlling particle thickness and uniformity, a magnetic conveying device, a controller and a It is composed of a signal feedback system, etc.; the solid particles fall evenly on the support plate of the conveying device, and the support plate is divided into a horizontal particle adding section and a particle heating section that slopes downward to the right; the magnetic conveying device is under the conveying device and is driven by the driving wheel. The belt transmission mechanism composed of driven wheel I, driven wheel II and magnetic conveyor belt with strong magnetic force controls the flow speed of magnetic solid particles on the support plate with the strong magnetic force provided by the magnetic conveyor belt; the signal feedback system collects the support Plate and solid particle temperature to adjust particle thickness and flow velocity. The invention realizes the flexible and controllable flow speed and thickness of the solid particles, and simply and effectively improves the light-to-heat conversion efficiency and operational safety and reliability of the particle heat absorber.

Description

Solar particle heat absorber for magnetic non-contact transportation of magnetic particles

Technical Field

The invention belongs to the field of solar light-gathering power generation, and relates to a heat absorber for solar thermal power generation, in particular to a solar particle heat absorber for magnetic non-contact transportation of magnetic particles.

Background

Solar energy is a clean, environment-friendly and widely distributed renewable energy source, and tower type solar high-temperature thermal power generation is a solar power generation technology which is commercialized and gradually improved. The heat absorber is core equipment of the tower type solar photothermal power station, and the light-heat conversion performance of the heat absorber directly influences the operation efficiency and the economy of the whole solar power station.

The heat absorbers adopted by the existing tower type solar thermal power plant are generally a molten salt heat absorber, a water working medium heat absorber, a heat conduction oil heat absorber and the like, the heat storage media corresponding to the heat absorbers are respectively nitrate, water, heat conduction oil and the like, the heat absorption temperature of the heat storage media is relatively low, and the thermoelectric efficiency of the rear end of the solar thermal power plant is severely limited. In order to improve the heat storage temperature of the heat storage medium, when the solid heat storage particles are used as the heat storage medium, the heat storage temperature can reach about 1000 ℃, the thermoelectric efficiency at the rear end of a solar thermal power plant can be greatly improved, the heat storage characteristics of the solid heat storage particles can be fully utilized, and the particle heat absorber is suitable for the particle heat absorber using the solid heat storage particles as the heat storage medium.

At present, solid particle heat absorbers are mainly divided into a free-falling type, a blocking-falling type, a rotary kiln type, a fluidized bed type and the like, and various solid particle heat absorbers have the advantages and the disadvantages. Free fall and blocked fall are widely concerned due to simple structures, but the free fall and blocked fall are based on gravity as natural main power, so that the falling speed of solid particles is difficult to control, the falling speed is high, the heat absorption time is short, and solar energy cannot be fully absorbed; the thickness of the particle heat absorption layer is uneven, so that the heat absorption temperature of solid particles is uneven in distribution and the hot spot problem is easy to occur; when solid particles directly fall to absorb heat, the solid particles are interfered by air flow inside the heat absorber or external environment wind, the particles fall to be scattered, and the flow path of the particles cannot be controlled. Therefore, the invention creates a new type of solar particle heat absorber with a particle flow mode, and realizes the flexible and controllable particle flow speed, thickness and uniformity of the solar particle heat absorber, thereby improving the light-heat conversion efficiency and the temperature distribution uniformity of the heat absorber, and being particularly important for engineering practice.

Disclosure of Invention

In order to solve the technical problems, the invention provides a magnetic-force non-contact magnetic particle transporting solar particle heat absorber with a simple structure and reliable operation, which controls the flow speed of magnetic solid particles through non-contact magnetic attraction, controls the thickness and the uniformity of a heated particle layer through a particle thickness control valve, realizes the uniform, flexible and controllable flow speed and thickness of the solid particles, and can effectively improve the light-heat conversion efficiency and the operation safety and reliability of the particle heat absorber.

The technical scheme adopted by the invention is as follows: a solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner comprises solid particles, a conveying device for conveying the solid particles, a particle distributor for containing the solid particles and uniformly distributing the particles to the conveying device, a flow control valve for controlling the particle flow at the outlet at the lower end of the particle distributor, a cavity cover, a particle collector and a particle collecting device, wherein one end of the cavity cover is surrounded by a secondary reflector with a heat-insulating layer on the outer side, a quartz window is installed at one end of the cavity cover, the other end of the cavity cover is close to a particle heating section in the conveying device, and the particle collector is used for collecting the solid particles heated by gathered sunlight at the tail end of the conveying device; the device also comprises a particle thickness control valve, a magnetic conveying device, a controller and a signal feedback system, wherein the particle thickness control valve is used for controlling the thickness of solid particles on the conveying device and improving the thickness uniformity; the solid particles are made of magnetic materials which can be attracted by magnetic force; the conveying device comprises a supporting plate for solid particle flowing and a heat insulator attached to the bottom surface of the supporting plate, the supporting plate consists of a particle adding section and a particle heating section, the particle adding section is horizontally arranged below the particle distributor, the particle heating section forms an included angle of more than 90 degrees with the horizontal plane and extends towards the lower right, and the two sections are in circular arc transition; the magnetic conveying device is positioned on the backlight side of the conveying device and comprises a driving wheel, a driven wheel I, a driven wheel II and a magnetic conveying belt, wherein the driving wheel, the driven wheel I and the driven wheel II are driven by a motor I, the magnetic conveying belt is provided with strong magnetic force and is slightly wider than a supporting plate, and a belt transmission mechanism is formed; the driving wheel is arranged on the left side of the particle distributor, the driven wheel I is arranged at the arc transition position of the supporting plate, the driven wheel II exceeds the tail end of the particle heating section of the supporting plate, and the sequential central connecting lines of the driving wheel, the driven wheel I and the driven wheel II are parallel to the supporting plate; the signal feedback system collects the temperature of the particle heating section of the supporting plate and the temperature of the solid particles and feeds the temperature back to the controller to control the flow control valve, the particle thickness control valve and the motor with the magnetic conveying device to work.

In the solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner, the particle thickness control valve is positioned on the right side of the particle distributor and comprises a motor IV, a gear II fixedly connected with the motor IV, a rack II meshed with the gear II and capable of sliding back and forth on a rack, and a baffle II arranged at the tail end of the rack II and having the same width as a supporting plate; baffle II is perpendicular to the particle addition section of backup pad and is located its top.

In the solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner, the solar particle heat absorber further comprises an electric push rod device; a hinge lug at one end of a screw rod in the electric push rod device is hinged with the base, and a hinge lug on a screw rod driving device in the electric push rod device is hinged with the frame; the particle conveying device, the particle distributor, the cavity cover, the particle collector and the magnetic conveying device are all fixed on the machine frame, and the machine frame is hinged with the machine base at a position close to the particle collector.

In the solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner, the conveying device further comprises a shovel plate and side baffles which are arranged on two sides of the supporting plate and used for preventing particles from scattering; one end of the shovel plate is closely attached to the front end of the tail end of the particle heating section in the supporting plate and forms an obtuse angle, and the shovel plate is obliquely directed to the particle collector.

In the solar particle heat absorber for magnetic non-contact magnetic particle transportation, the signal feedback system comprises a signal collector, a plurality of thermocouples embedded in the particle heating section in the supporting plate, and an infrared camera temperature collector which is forcibly cooled by air and is arranged in the heat insulation layer of the cavity cover; the secondary reflector on one side of the cavity cover is provided with an observation hole and a glass window with high infrared radiation transmittance, and the infrared camera temperature collector measures the particle temperature of the particle heating section in the supporting plate through the glass window; and the signal collector receives the signal of the thermocouple and the temperature information processed by the infrared camera temperature collector.

In the solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner, the magnetic conveyer belt is made of a soft conveyer belt made of strong magnet materials or a plurality of strong magnets adhered to the surface of a common conveyer belt.

In the solar particle heat absorber for transporting magnetic particles in a magnetic non-contact manner, the support plate is made of a high-temperature-resistant material which is not easy to magnetize and can allow a magnetic field of the magnetic conveyor belt to pass through.

Compared with the prior art, the invention has the beneficial effects that:

1) the magnetic conveying device is arranged below the conveying device, the magnetic conveying belt in the magnetic conveying device provides magnetic force to further pull the magnetic solid particles on the supporting plate in the conveying device to flow, and the flow speed of the solid particles can be effectively controlled by controlling the movement speed of the magnetic conveying belt; 2) in the invention, solid particles are adsorbed on the supporting plate in the conveying device by the magnetic force of the magnetic conveying belt to flow, and are not scattered like free falling of the particles; 3) according to the invention, the thickness of solid particles on the conveying device is flexibly controlled through the particle thickness control valve, and the thickness uniformity is improved; 4) according to the invention, the electric push rod device is arranged on the heat absorber, so that the inclination angle of the heat absorber can be adjusted to match the distribution change of the focusing energy flow caused by the change of the position and posture of the sun; 5) the invention adopts a plurality of thermocouples and infrared camera temperature collectors which are embedded in the supporting plate to respectively measure the temperature of the particle heating section and the solid particles in the supporting plate, and the temperature is fed back to control the particle thickness and the flow speed, thereby effectively improving the light-heat conversion efficiency and the operation safety and reliability of the solar particle heat absorber.

Drawings

Fig. 1 is a schematic diagram of the structure of a solar granular heat absorber according to the present invention.

FIG. 2 is an enlarged view of a portion of the blanking area of the particle dispenser of FIG. 1.

In the figure: 1-a particle dispenser; 2-a flow control valve; 201-motor iii; 202-gear i; 203-rack I; 204-baffle I; 3-particle thickness control valve; 301-motor iv; 302-gear ii; 303-rack ii; 304-baffle ii; 4-a conveying device; 401 — side dams; 402-a support plate; 403-heat insulation body; 404-shovel plate; 405-a particle heating section; 5, carrying a magnetic conveying device; 501, a motor I; 502-drive wheel; 503-driven wheel I; 504-driven wheel II; 505-a tensioner; 506-a magnetic conveyer belt; 6, an electric push rod device; 601-motor II; 602-a lead screw; 7-a controller; 8-signal feedback system; 801-signal collector; 802-thermocouple; 803-infrared camera temperature collector; 9-a particle collector; 10-a cavity cover; 101-insulating layer; 102 — a secondary reflector; 103-quartz window; 104-a glass window; 11-a machine base; 12-a frame; 13-solid particles.

Detailed Description

The invention will be further described with reference to the accompanying drawings.

As shown in FIG. 1, the present invention comprises a solid particle 13 for absorbing solar energy and converting the solar energy into heat energy, a conveying device 4 for conveying the solid particle 13, a particle distributor 1 for containing the solid particle 13 and uniformly distributing the particles to the conveying device 4, a flow control valve 2 for controlling the particle flow rate at the lower end of the particle distributor 1, a chamber cover 10 which is surrounded by a secondary reflector 102 with an insulating layer 101 on the outer side and has one end provided with a quartz window 103 and the other end adjacent to a particle heating section 405 in the conveying device 4, and a particle collector 9 at the end of the conveying device 4 for collecting the solid particles heated by the concentrated solar energy. The solar particle heat absorber further comprises a particle thickness control valve 3, a magnetic conveying device 5, a controller 7 and a signal feedback system 8, wherein the particle thickness control valve is used for controlling the thickness of solid particles 13 on the conveying device 4 and improving the thickness uniformity; the solid particles 13 for the heat absorber are made of a magnetic material that can be attracted by magnetic force. The conveying device 4 comprises a supporting plate 402 for flowing the solid particles 13 and a heat preservation body 403 attached to the bottom surface of the supporting plate 402, wherein the supporting plate 402 is composed of a particle adding section horizontally arranged below the particle distributor 1 and a particle heating section 405 which forms an included angle of more than 90 degrees with the horizontal and extends towards the lower right, and the two sections are in circular arc transition. The magnetic conveyor 5 is located on the backlight side below the conveyor 4, and the magnetic conveyor 5 includes a driving pulley 502 driven by a motor i 501, a driven pulley i 503, a driven pulley ii 504, and a magnetic conveyor 506 having a strong magnetic force and slightly wider than the support plate 402, which constitute a belt transmission mechanism, and a tension pulley 505 for tensioning the magnetic conveyor 506 is provided. The driving wheel 502 is positioned at the left side of the particle distributor 1, namely below the region on the supporting plate 402 where no solid particles are added, the driven wheel I503 is positioned at the arc transition position of the supporting plate 402, and the driven wheel II 504 exceeds the tail end of the particle heating section 405 of the supporting plate 402; the connecting line of the centers of the driving wheel 502, the driven wheel I503 and the driven wheel II 504 in sequence is kept parallel to the particle adding section and the particle heating section 405 of the supporting plate 402 respectively, so that the tensioned magnetic conveying belt 506 is also kept parallel to the supporting plate 402, and the magnetic field suction force of the magnetic conveying belt 506 keeps the same to the solid particles 13 in each area on the supporting plate 402. According to the invention, the magnetic conveying device 5 is arranged below the conveying device 4, the magnetic conveying belt 506 in the magnetic conveying device 5 provides magnetic force, so that the magnetic solid particles on the supporting plate 402 in the conveying device 4 are pulled to flow, and the flow speed of the solid particles can be effectively controlled by controlling the movement speed of the magnetic conveying belt 506; since the solid particles 13 are attracted to the flow path of the support plate 402 in the conveyor 4 by the magnetic force of the magnetic conveyor belt 506, they are not scattered as if they were free falling. The sunlight collected by the condenser penetrates through the quartz window 103, a part of the sunlight is projected to the surface of the solid particles of the particle heating section 405 of the support plate 402 and absorbed by the solid particles, and the other part of the sunlight is reflected to the solid particles through the secondary reflector 102 and absorbed by the solid particles, so that the light-heat conversion is realized.

The signal feedback system 8 comprises a signal collector 801, a plurality of thermocouples 802 embedded in the particle heating section 405 of the support plate 402, and an infrared camera temperature collector 803 which is cooled by air force and is arranged in the insulating layer 101 of the cavity cover 10; the secondary reflector 102 on one side of the chamber cover 10 is provided with an observation hole and is provided with a glass window 104 with high infrared radiation transmittance, and the infrared camera temperature collector 803 measures the particle temperature of the particle heating section 405 in the support plate 402 through the glass window 104; the signal collector 801 receives the signal of the thermocouple 801 and the temperature information processed by the infrared camera temperature collector 803, and feeds the signal back to the controller 7 to control the flow control valve, the particle thickness control valve and the motor with the magnetic conveying device to work, thereby realizing the control of the particle thickness and the flow speed, and effectively improving the light-heat conversion efficiency and the operation safety and reliability of the solar particle heat absorber.

As shown in fig. 1 and 2, the particle thickness control valve 3 is located at the right side of the particle distributor 1, and comprises a motor iv 301, a gear ii 302 fixedly connected with the motor iv 301, a rack ii 303 engaged with the gear ii 302 and capable of sliding back and forth on the frame 12, and a baffle ii 304 arranged at the end of the rack ii 303 and having the same width as the support plate 402; the baffle II 304 is vertical to and above the particle adding section of the supporting plate 402, and the height of the tail end of the baffle II 304 and the height of the particle adding section of the supporting plate 402 are adjusted by driving a gear rack mechanism through the motor IV 301, so that the thickness of the solid particles 13 on the supporting plate 402 in the conveying device 4 can be flexibly controlled, and the uniformity of particle distribution is improved.

As shown in fig. 1, the solar particle heat absorber of the present invention further includes an electric push rod device 6, wherein a hinge lug at one end of a screw 602 in the electric push rod device 6 is hinged with the frame 11, and a hinge lug on a screw driving device in the electric push rod device 6 is hinged with the frame 12; the conveying device 4, the particle distributor 1, the chamber cover 10, the particle collector 9, the magnetic conveying device 5 and the like are all fixed on a frame 12, and the frame 12 is hinged with a base 11 at a position close to the particle collector 9. Because the electric push rod device 6 is arranged on the solar particle heat absorber, the inclination angle of the whole particle heat absorber can be adjusted through the extension and retraction of the screw rod 602 so as to match the energy flow distribution change of the particle adding section 405 focused on the supporting plate 402 caused by the change of the solar pose when a series of tower-type heliostats operate, and the light-heat conversion efficiency and the operation safety and reliability of the solar particle heat absorber can be effectively improved.

Preferably, the conveying device 4 further comprises a shovel plate 404 and side baffles 401 arranged on both sides of the supporting plate 402 for blocking particles from scattering; one end of the blade 404 is positioned at an obtuse angle with respect to the support plate 402 before the end of the particle heating section 405, and the blade 404 is directed obliquely towards the particle collector 9, as shown in fig. 1.

Preferably, the magnetic belt 506 is a soft belt made of a ferromagnetic material or a belt made of a common belt with a plurality of ferromagnetic materials adhered to the surface thereof.

Preferably, the support plate 402 is made of a high temperature resistant material that is not easily magnetized and that allows the magnetic field of the magnetic conveyor belt 506 to pass through.

As shown in FIGS. 1 and 2, the flow control valve 2 is positioned at the lower outlet position of the particle distributor 1, and comprises a gear I202 fixedly connected with a motor III 201, a rack I203 meshed with the gear I202 and parallel to the particle adding section of a supporting plate 402 and capable of sliding back and forth on the rack 12, and a baffle I204 arranged at the tail end of the rack I203; the tip blade of this baffle I204 is laminated with the lower extreme export of granule distributor 1 for adjust the size of export circulation cross-section.

Claims

1. A solar particle heat absorber for magnetic non-contact transportation of magnetic particles, comprising solid particles, a conveying device for conveying solid particles, a particle distributor for containing solid particles and evenly distributing the particles to the conveying device, and a control particle distributor A flow control valve for particle flow at the lower end outlet, a quartz window is installed at one end surrounded by a secondary reflector with a thermal insulation layer on the outside, and the other end is close to the cavity cover of the particle heating section in the conveying device, and the concentrated sunlight is collected at the end of the conveying device. A particle collector for heated solid particles; characterized in that it further comprises a particle thickness control valve, a magnetic conveying device, a controller and a signal feedback system for controlling the thickness of solid particles on a conveying device and improving thickness uniformity; the The solid particles are made of magnetic materials that can be attracted by magnetic force; the conveying device includes a support plate for the flow of solid particles and a heat preservation body attached to the bottom surface of the support plate, and the support plate is arranged horizontally under the particle distributor. The particle adding section and the particle heating section with an included angle of more than 90° from the horizontal and extending to the lower right are composed of the two sections, and there is an arc transition between the two sections; the magnetic conveying device is located on the backlight side of the conveying device, and it includes a motor The driving wheel driven by I, the driven wheel I, the driven wheel II and the magnetic conveyor belt with strong magnetic force and slightly wider than the support plate constitute a belt transmission mechanism; the driving wheel is on the left side of the particle distributor, and the driven wheel I is on the support plate. The arc transition position of the driven wheel II is beyond the end of the particle heating section of the support plate, and the center line of the driving wheel, the driven wheel I and the driven wheel II in turn is parallel to the support plate; the signal feedback system collects the particles of the support plate. The temperature of the heating section and the solid particles is fed back to the controller to control the flow control valve, the particle thickness control valve and the electric motor with the magnetic conveying device.

2. The solar particle heat absorber for magnetic non-contact transportation of magnetic particles according to claim 1, characterized in that: the particle thickness control valve is located on the right side of the particle distributor, and it comprises a motor IV and is fixed to the motor IV The connected gear II, the rack II that meshes with the gear II and can slide back and forth on the frame, the baffle II that is arranged at the end of the rack II and has the same width as the support plate; the baffle II is perpendicular to the particle adding section of the support plate and above it.

3. The solar particle heat absorber for magnetic non-contact transportation of magnetic particles according to claim 1, characterized in that: it also comprises an electric push rod device; in the electric push rod device, one end hinge ear of the screw rod is hinged with the machine base , the hinge ear on the screw drive device in the electric push rod device is hinged with the frame; the conveying device, particle distributor, cavity cover, particle collector and magnetic conveying device are all fixed on the frame. The frame is hinged to the base near the particle collector.

4 . The solar particle heat absorber for magnetic non-contact transportation of magnetic particles according to claim 1 , wherein the conveying device further comprises a shovel plate and side baffles installed on both sides of the support plate to prevent particles from scattering. 5 . ; One end of the shovel plate is in close contact with the end of the particle heating section in the support plate and is at an obtuse angle, and the shovel plate is inclined to point to the particle collector.

5 . The solar particle heat absorber for magnetic non-contact transport of magnetic particles according to claim 1 , wherein the signal feedback system comprises a signal collector, a plurality of thermoelectric generators embedded in the particle heating section in the support plate. 6 . Even, the infrared camera temperature collector installed in the insulation layer of the cavity cover with forced air cooling; the secondary reflector on one side of the cavity cover is provided with an observation hole, and a glass window with high infrared radiation transmittance is installed. The infrared camera temperature collector measures the particle temperature of the particle heating section in the support plate through the glass window; the signal collector receives the signal of the thermocouple and the temperature information processed by the infrared camera temperature collector.

6. The solar particle heat absorber for magnetic non-contact transportation of magnetic particles according to claim 1, characterized in that: the magnetic conveyor belt is a soft conveyor belt manufactured by adding strong magnet materials or in a common conveyor belt. Manufactured by pasting several strong magnets on the surface of the belt.

7 . The solar particle heat absorber for magnetic non-contact transport of magnetic particles according to claim 1 , wherein the support plate is a high temperature resistant material that is not easy to be magnetized and can pass through the magnetic field of the magnetic conveyor belt. 8 . Material manufacturing.