Rotational flow fluidization heat absorber and solar photo-thermal power generation system

Abstract

The invention relates to the technical field of solar heat collectors, and provides a rotational flow fluidization heat absorber which comprises a heat absorption assembly provided with a bottom ring pipe and a top ring pipe, and a plurality of heat absorption pipes are connected between the bottom ring pipe and the top ring pipe in parallel; a fluidization gas pipe is arranged on the bottom ring pipe; a rotational flow pipe is arranged in the heat absorption pipe, and a feeding branch pipe is arranged at the lower end of the rotational flow pipe; at least one spiral blade extending in the axial direction is arranged on the inner wall of the rotational flow pipe; the temporary storage bin is used for storing solid particles; the distributor is arranged below the temporary storage bin and is connected with a discharge pipe of the temporary storage bin; and the gas-solid separator is provided with a mixture pipe connected with the top ring pipe. Therefore, the rotational flow pipe is arranged in the heat absorption pipe, and rotational flow gas and solid particles form spirally flowing particle fluid; under the action of centrifugal force, the solid particles are attached to the inner wall of the heat absorption pipe to form a particle layer with small thickness, the influence of the temperature gradient in the pipe is avoided, and the heat exchange efficiency is improved. The invention provides a solar photo-thermal power generation system.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar thermal collectors, and in particular relates to a swirling fluidized heat absorber and a solar thermal power generation system. Background Art

[0002] Solar thermal absorbers are key components in solar thermal power generation systems, and their performance directly affects the efficiency and economy of the entire solar thermal power generation system. According to the different heat transfer fluid media in the solar thermal absorber, the absorber can be divided into three types: gas, liquid and solid.

[0003] Among them, the solid heat absorber uses solid particles as the heat absorption medium, which has good absorption performance and high volume heat capacity, and the operating temperature can exceed 1000℃. Its heat absorption method is usually that the outer surface of the heat absorption tube is exposed to sunlight and absorbs heat, and the solid particles flow through the tube and contact the inner wall of the tube to absorb and take away the heat. Since the temperature of the tube wall is much higher than the temperature of the center of the tube, the heat absorption effect of the solid particles far away from the inner wall of the tube is poor, which reduces the heat absorption efficiency.

[0004] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0005] In view of the above-mentioned defects, the present invention mainly provides a swirl fluidized bed heat absorber to solve the technical problem of reduced heat exchange efficiency of solid particles due to temperature gradient in the tube.

[0006] In order to solve the above problems, the present invention provides a cyclone fluidized heat absorber, comprising:

[0007] The heat absorption component comprises a bottom ring tube and a top ring tube, wherein a plurality of heat absorption tubes are connected in parallel between the bottom ring tube and the top ring tube; a fluidizing gas pipe is arranged on the bottom ring tube; a swirl tube is arranged inside the heat absorption tube, and a feed branch pipe is arranged at the lower end of the swirl tube; and at least one spiral blade extending in the axial direction is arranged on the inner wall of the swirl tube;

[0008] A temporary storage bin is used to store solid particles; a feed pipe is provided at the top of the temporary storage bin, and a discharge pipe is provided at the bottom;

[0009] A material distributor is arranged below the temporary storage bin and connected to its discharge pipe; the material distributor is also connected to the feed branch pipe of the cyclone tube; the material distributor is also provided with a cyclone air pipe;

[0010] The gas-solid separator comprises a mixed material pipe connected to the top ring pipe, a gas pipe and a solid material pipe.

[0011] According to the swirl fluidized heat absorber of the present invention, 3-6 spiral blades are provided on the inner wall of the swirl tube.

[0012] According to the swirl fluidized heat absorber of the present invention, a support column is provided at the center of the swirl tube, and the spiral blades are arranged in a hollow layer between the support column and the inner wall of the swirl tube.

[0013] According to the cyclone fluidized heat absorber of the present invention, a plurality of partition plates are evenly arranged in a circle inside the distributor, and a batching cavity is formed between two adjacent partition plates; the number of the batching cavities is the same as the number of heat absorption tubes, and each batching cavity corresponds to a feed branch of a cyclone tube connected to a heat absorption tube.

[0014] According to the swirl fluidized bed heat absorber of the present invention, the number of the batching chambers is the same as the number of the discharge pipes of the temporary storage bin, and each batching chamber is correspondingly connected to a discharge pipe.

[0015] According to the swirling fluidized heat absorber of the present invention, the heat absorption tube has a length of 2 to 3 m and a tube diameter of 40 to 60 mm; the pitch of the spiral blade is 40 to 60 mm and the length is 120 to 200 mm.

[0016] According to the swirl fluidized bed heat absorber of the present invention, the discharge pipe is also connected to a control valve.

[0017] According to the swirl fluidized bed heat absorber of the present invention, the bottom ring tube and the top ring tube are both circular ring structures, and a clearance space is formed in the center; the temporary storage bin, gas-solid separator, and distributor are all arranged in the clearance space.

[0018] A solar thermal power generation system, comprising:

[0019] The tower frame has the swirling fluidized heat absorber installed on its top:

[0020] A plurality of heliostats are arranged around the tower to reflect sunlight onto the heat absorbing tubes of the absorber;

[0021] An air supply unit, connecting the fluidizing air pipe and the cyclone air pipe of the heat absorber;

[0022] A hot material tank connected to the discharge pipe of the temporary storage bin of the heat absorber; used to store high-temperature solid particles after heat exchange;

[0023] A cold material tank connected to the feed pipe of the temporary storage bin of the heat absorber; used for conveying low-temperature solid particles to the temporary storage bin;

[0024] The power generation unit comprises a heat exchanger; the heat exchanger has a heat exchange coil, and the heat exchange coil is respectively connected to a hot material tank and a cold material tank; the heat exchanger is also connected to a steam turbine and a heat regenerator; the steam turbine is connected to a generator.

[0025] According to the solar thermal power generation system of the present invention, the gas storage tank is connected to an air compressor.

[0026] In summary, the swirl fluidized heat absorber of the present invention forms a spirally flowing granular fluid with swirl gas and solid particles by arranging a swirl tube in the heat absorbing tube; under the action of centrifugal force, the solid particles adhere to the inner wall of the heat absorbing tube to form a particle layer, and the particle layer flows upward along the inner wall of the heat absorbing tube in a spiral posture. During the flow process, heat exchange is completed between the solid particles and the heat absorbing tube. Due to the action of centrifugal force, the thickness of the particle layer is small, avoiding the influence of the temperature gradient in the heat absorbing tube, and can fully absorb the heat of the heat absorbing tube, thereby improving the heat exchange efficiency. The present invention provides a solar thermal power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the swirl fluidized heat absorber of the present invention;

[0028] Figure 2 yes Figure 1 A schematic diagram of a partial cross-section structure;

[0029] Figure 3 yes Figure 2 A schematic diagram of the cross-sectional structure along the middle A direction;

[0030] Figure 4 It is a schematic cross-sectional structure diagram of the heat absorption tube of the present invention;

[0031] Figure 5 It is a schematic cross-sectional view of the cyclone tube of the present invention;

[0032] Figure 6 It is a structural schematic diagram of the solar thermal power generation system of the present invention;

[0033] In the figure: 1-bottom ring pipe, 11-fluidizing gas pipe; 2-top ring pipe, 3-heat absorption pipe, 31-feed branch pipe, 32-spiral blade, 33-support column, 34-swirl pipe; 4-temporary storage bin, 41-feed pipe, 42-discharge pipe, 43-control valve; 5-gas-solid separator, 51-gas pipe, 52-mixing pipe, 53-solid pipe; 6-distributor, 61-swirl gas pipe, 62-partition plate, 63-dosing chamber; 7-tower, 71-heliostat, 72-cold material tank, 73-hot material tank, 74-gas storage tank, 75-air compressor; 8-heat exchanger, 81-steam turbine, 82-generator, 83-regenerator; 100-heat absorber. DETAILED DESCRIPTION

[0034] See also Figure 1 The present invention provides a swirling fluidized heat absorber, comprising:

[0035] The heat absorption component comprises a bottom ring tube 1 and a top ring tube 2, wherein a plurality of heat absorption tubes 3 are connected in parallel between the bottom ring tube 1 and the top ring tube 2; the heat absorption tubes 3 are heated up by sunlight and absorb solar energy. Preferably, the outer wall of the heat absorption tube 3 of the present invention is black to improve the heat absorption efficiency.

[0036] The bottom ring pipe 1 is provided with a fluidizing gas pipe 11; the fluidizing gas pipe 11 is configured to: introduce fluidizing gas and blow it from the bottom ring pipe 1 into each heat absorbing tube 3, so that the solid particles accumulated at the bottom of the heat absorbing tube 3 are in a tumbling state;

[0037] See also Figure 4 The heat absorption tube 3 is provided with a swirl tube 34, and the lower end of the swirl tube 34 is provided with a feed branch pipe 31; Figure 5 , the inner wall of the swirl tube 34 is provided with at least one spiral blade 32 extending in the axial direction;

[0038] A temporary storage bin 4 is used to store solid particles; a feed pipe 41 is provided at the top of the temporary storage bin 4, and a discharge pipe 42 is provided at the bottom;

[0039] See also Figure 2 , a distributor 6 is arranged below the temporary storage bin 4 and connected to its discharge pipe 42; the distributor 6 is also connected to the feed branch pipe 31 of the cyclone tube 34; the distributor 6 is also provided with a cyclone air pipe 61;

[0040] The gas-solid separator 5 has a mixing material pipe 52 connected to the top ring pipe 2, a gas pipe 51 and a solid material pipe 53. The solid particles and the airflow that have completed the heat exchange in the heat absorbing pipe 3 enter the gas-solid separator 5 from the mixing material pipe 52. Under the action of gravity, the solid particles with higher density flow downward from the solid material pipe 53, and the gas with lower density flows upward from the gas pipe 51.

[0041] The swirl gas pipe 61 is configured as follows: the swirl gas is introduced to deliver the solid particles in the distributor 6 into the swirl tube 34; under the guiding effect of the spiral blades 32 in the swirl tube 34, the swirl gas drives the solid particles to form a granular fluid with a spiral upward flow; under the effect of inertia, the granular fluid flows out from the top of the swirl tube 34 and still flows along the inner wall of the heat absorption tube 3 in a spiral posture until it enters the top ring tube 2.

[0042] Under the action of centrifugal force, the solid particles in the granular fluid adhere to the inner wall of the heat absorbing tube 3 to form a particle layer, and the particle layer flows upward along the inner wall of the heat absorbing tube 3 in a spiral posture. During the flow, heat exchange is completed between the solid particles and the heat absorbing tube 3. Due to the action of centrifugal force, the thickness of the particle layer is small, which avoids the influence of the temperature gradient in the heat absorbing tube, can fully absorb the heat of the heat absorbing tube 3, and improve the heat exchange efficiency.

[0043] The solid particles in the heat absorbing tube 3 enter the top ring tube 2 from the top opening; the flow rate of the swirling gas can be adaptively set according to the material and particle size of the solid particles, the size of the heat absorbing tube 3, etc.

[0044] Optionally, the heat absorbing tube 3 of the present invention has a length of 2 to 3 m and a tube diameter of 40 to 60 mm, thereby ensuring sufficient heat exchange and allowing the solid particles to reach a relatively high temperature.

[0045] Furthermore, the pitch of the spiral blade 32 is 40-60 mm, and the length is 120-200 mm, so that the solid particles can form a spiral particle fluid with sufficient initial velocity.

[0046] Optionally, the solid particles of the present invention are made of silicon carbide, silicon dioxide or aluminum oxide; the particle size is preferably 60-80 μm.

[0047] A small amount of particles in the particle fluid in the heat absorbing tube 3 will stall and fall to the bottom of the heat absorbing tube 3. Fluidizing gas is introduced from the fluidizing gas pipe 11 and blown into each heat absorbing tube 3 from the bottom ring tube 1, so that the solid particles accumulated at the bottom of the heat absorbing tube 3 are in a tumbling and bulging state. The temperature of the particles accumulated for a long time is high, and the temperature of the newly fallen particles is low. The fluidizing gas can mix the two in real time to make their temperature areas consistent.

[0048] When the accumulated particles at the bottom of the heat absorption tube 3 are blown by the fluidizing gas to a height that reaches or exceeds the upper opening of the cyclone tube 34, they are carried away by the particle fluid discharged from the cyclone tube 34, so that the amount of particle accumulation at the bottom of the heat absorption tube 3 reaches a dynamic balance.

[0049] As an embodiment, 3-6 spiral blades 32 are provided on the inner wall of the cyclone tube 34, which can simultaneously form multiple spiral particle fluids with different initial phases, thereby improving the conveying efficiency of solid particles.

[0050] Furthermore, a support column 33 is provided at the center of the cyclone tube 34, and the spiral blades 32 are arranged in a hollow layer between the support column 33 and the inner wall of the cyclone tube 34; separated by the support column 33, multiple spiral particle fluids do not contact each other, thereby preventing solid particles from stalling and falling due to collision, so that each spiral particle fluid has a higher initial velocity when flowing out from the upper port of the cyclone tube 34, and can enter the top ring tube 2, thereby reducing the amount of particles that stall and fall in the heat absorption tube 3.

[0051] See also Figure 3As an embodiment, a plurality of partition plates 62 are evenly arranged in a circle in the distributor 6, and a batching cavity 63 is formed between two adjacent partition plates 62; the number of the batching cavities 63 is the same as the number of the heat absorption tubes 3, and each batching cavity 63 corresponds to a feed branch pipe 31 of a vortex tube 34 connected to a heat absorption tube 3; an equal amount of solid particles enters each heat absorption tube 3 to avoid excess heat or insufficient heat supply in some heat absorption tubes 3 due to different amounts of solid particles in different heat absorption tubes 3.

[0052] Furthermore, the number of the batching chambers 63 is the same as the number of the discharge pipes 42 of the temporary storage bin 4, and each batching chamber 63 is connected to a corresponding discharge pipe 42; the solid particles in the temporary storage bin 4 are equally divided into the batching chambers 63 through each discharge pipe 42, which facilitates uniform feeding.

[0053] Better yet, in order to prevent the swirling gas from blowing the solid particles back to the temporary storage bin 4, the discharge pipe 42 is also connected to a control valve 43;

[0054] As an embodiment, the bottom ring tube 1 and the top ring tube 2 are both circular structures, and a clearance space is formed in the center; the temporary storage bin 4, the gas-solid separator 5, and the distributor 6 are all arranged in the clearance space; the outside of the heat absorption tube 3 of the heat absorption component is unobstructed and can fully absorb solar energy.

[0055] The swirl fluidized heat absorber of the present invention is provided with a swirl tube 34 in the heat absorbing tube 3, so that the swirl gas and solid particles form a spirally flowing particle fluid; under the action of centrifugal force, the solid particles adhere to the inner wall of the heat absorbing tube 3 to form a particle layer, and the particle layer flows upward along the inner wall of the heat absorbing tube 3 in a spiral posture. During the flow process, heat exchange is completed between the solid particles and the heat absorbing tube 3. Due to the action of the centrifugal force, the thickness of the particle layer is small, which avoids being affected by the temperature gradient in the heat absorbing tube, can fully absorb the heat of the heat absorbing tube 3, and improve the heat exchange efficiency.

[0056] See also Figure 6 The present invention also provides a solar thermal power generation system, comprising:

[0057] The tower 7 has the heat absorber 100 installed on its top:

[0058] A plurality of heliostats 71 are arranged around the tower 7 to reflect sunlight onto the heat absorbing tube 3 of the heat absorber 100 to improve the heat absorption efficiency;

[0059] A gas supply unit, connected to the fluidizing gas pipe 11 and the cyclone gas pipe 61 of the heat absorber 100; used to provide fluidizing gas and cyclone gas;

[0060] Optionally, the air supply unit of the present invention is a fan;

[0061] Optionally, the gas supply unit of the present invention includes a gas storage tank 74, and the gas storage tank 74 is connected to an air compressor 75; the gas storage tank 74 provides fluidizing gas and swirl gas with controllable air pressure;

[0062] The hot material tank 73 is connected to the discharge pipe 42 of the temporary storage bin 4 of the heat absorber 100 and is used to store high-temperature solid particles after heat exchange;

[0063] The cold material tank 72 is connected to the feed pipe 41 of the temporary storage bin 4 of the heat absorber 100 and is used to transport low-temperature solid particles to the temporary storage bin 4;

[0064] The power generation unit includes a heat exchanger 8; the heat exchanger 8 has a heat exchange coil, and the heat exchange coil is connected to the hot material tank 73 and the cold material tank 72 respectively; the heat exchanger 8 is also connected to the steam turbine 81 and the regenerator 83; the steam turbine 81 is connected to the generator 82;

[0065] The liquid water in the regenerator 83 exchanges heat with the heat exchange coil in the heat exchanger 8 to form water vapor, which drives the steam turbine 81 to drive the generator 82 to generate electricity; then it is condensed into liquid water in the regenerator 83.

[0066] The solar thermal power generation system of the present invention realizes the conversion of solar energy into electrical energy by using solid particles as a medium, thereby providing green energy.

[0067] In summary, the present invention provides a swirl fluidized heat absorber, in which a swirl tube is arranged in a heat absorbing tube, and the swirl gas and solid particles form a spirally flowing granular fluid; under the action of centrifugal force, the solid particles adhere to the inner wall of the heat absorbing tube to form a particle layer, and the particle layer flows upward along the inner wall of the heat absorbing tube in a spiral posture. During the flow process, heat exchange is completed between the solid particles and the heat absorbing tube. Due to the action of centrifugal force, the thickness of the particle layer is small, avoiding the influence of the temperature gradient in the heat absorbing tube, and can fully absorb the heat of the heat absorbing tube, thereby improving the heat exchange efficiency. The present invention provides a solar thermal power generation system.

[0068] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A cyclonic fluidized bed heat absorber, characterized in that: include: The heat absorption component comprises a bottom ring tube and a top ring tube, wherein a plurality of heat absorption tubes are connected in parallel between the bottom ring tube and the top ring tube; a fluidizing gas pipe is arranged on the bottom ring tube; a swirl tube is arranged inside the heat absorption tube, and a feed branch pipe is arranged at the lower end of the swirl tube; and at least one spiral blade extending in the axial direction is arranged on the inner wall of the swirl tube; A temporary storage bin is used to store solid particles; a feed pipe is provided at the top of the temporary storage bin, and a discharge pipe is provided at the bottom; A material distributor is arranged below the temporary storage bin and connected to its discharge pipe; the material distributor is also connected to the feed branch pipe of the cyclone tube; the material distributor is also provided with a cyclone air pipe; The gas-solid separator comprises a mixed material pipe connected to the top ring pipe, a gas pipe and a solid material pipe.

2. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: The inner wall of the cyclone tube is provided with 3-6 spiral blades.

3. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: A support column is provided at the center of the cyclone tube, and the spiral blades are arranged in a hollow layer between the support column and the inner wall of the cyclone tube.

4. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: A plurality of partition plates are evenly arranged in a circle in the distributor, and a batching cavity is formed between two adjacent partition plates; the number of the batching cavities is the same as the number of the heat absorbing tubes, and each batching cavity corresponds to a feed branch pipe of a cyclone tube connected to a heat absorbing tube.

5. The swirling fluidized bed heat absorber according to claim 4, characterized in that: The number of the batching chambers is the same as the number of the discharge pipes of the temporary storage bin, and each batching chamber is connected to a corresponding discharge pipe.

6. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: The heat absorbing tube has a length of 2 to 3 m and a tube diameter of 40 to 60 mm; the spiral blade has a pitch of 40 to 60 mm and a length of 120 to 200 mm.

7. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: The discharge pipe is also connected to a control valve.

8. The cyclone fluidized bed heat absorber according to claim 1, characterized in that: The bottom ring tube and the top ring tube are both circular structures, and a clearance space is formed in the center; the temporary storage bin, the gas-solid separator, and the distributor are all arranged in the clearance space.

9. A solar thermal power generation system, characterized in that: include: A tower, on the top of which is mounted a cyclonic fluidized bed heat absorber as claimed in any one of claims 1 to 8: A plurality of heliostats are arranged around the tower to reflect sunlight onto the heat absorbing tubes of the absorber; An air supply unit, connecting the fluidizing air pipe and the cyclone air pipe of the heat absorber; A hot material tank connected to the discharge pipe of the temporary storage bin of the heat absorber; used to store high-temperature solid particles after heat exchange; A cold material tank connected to the feed pipe of the temporary storage bin of the heat absorber; used for conveying low-temperature solid particles to the temporary storage bin; The power generation unit comprises a heat exchanger; the heat exchanger has a heat exchange coil, and the heat exchange coil is respectively connected to a hot material tank and a cold material tank; the heat exchanger is also connected to a steam turbine and a heat regenerator; the steam turbine is connected to a generator.

10. The solar thermal power generation system according to claim 9, characterized in that: The air storage tank is connected to an air compressor.

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