JP3218262U - Heating medium heating device - Google Patents

Abstract

A heat medium heating device that converts solar heat energy into high-temperature air energy through a heat medium and a solar power generation device that turns an air turbine generator to convert into electric energy are provided.
A heat medium heating tube assembly 3 that passes a mixture of ceramic particles, metal oxides or refractory metal solid particles serving as a heat medium, and nitrogen gas or air inside and heats the mixture by solar heat; Supplyed from the air compressor 31 or the air blower in the storage tank that stores the heated mixture connected to the heating medium heating tube assembly 3 and the heated mixture supplied from the storage tank connected to the storage tank. And an air heater 21 for heating air. It has a damper mechanism for stopping the delivery of the mixture from the storage tank to the air heater 21 and switching to the heat medium heating tube assembly 3 for delivery.
[Selection] Figure 1

Description

  The present invention relates to a heating medium heating device that converts solar thermal energy into high-temperature air energy through a heating medium. Or it is related with the solar thermal power generation device which turns an air turbine generator and converts it into an electrical energy.

  Regarding a device for converting solar thermal energy into electric energy using a mixed phase heat medium in which small solids and gas are mixed, in the previous example, Japanese Patent Application Laid-Open No. 2011-214425, mixed phase heat medium supply in which small solids and gas are mixed A solar thermal power generation apparatus using the apparatus and a solar heat receiving apparatus is described. Furthermore, a steam superheat heat exchanger for superheating boiler generated steam using the mixed phase heat medium is described.

  In a preceding example of another solar concentrating solar power generator (see Utility Model Registration No. 3170751), a large number of solar heat receivers are provided on a high steel tower or the like to obtain a high-temperature heat medium, and a large amount of pressure liquid is provided there. It is disclosed that a heat medium such as liquid air or liquid nitrogen is transferred. Liquid air and liquid nitrogen heat media are more expensive than other types of heat media. Moreover, it is necessary to always manage the low temperature and high pressure of this type of heat medium, which complicates operability.

  Japanese Patent No. 6320228 discloses a solar power generation apparatus that uses an air turbine without using a conventional steam turbine as a turbine for driving a generator.

JP 2011-214425 A Utility Model Registration No. 3170751 Japanese Patent No. 6320228

  In the solar thermal power generation apparatus using the mixed phase heat medium shown in the preceding example (Patent Document 1), nitrogen gas or air is introduced as the gas. It is disclosed that ceramic particles and metal particles are used as solid particles having a solid-gas ratio (solid particle / transport gas weight ratio) of 5 to 100 times, but how much solar heat is received efficiently. No specific solar heating device is described. Further, there is no specific example of how to use the solid particles to superheat boiler-generated steam to produce heated steam and drive a steam turbine generator to generate electricity. Furthermore, there is no description about a device for storing solar heat, and there are explanations of measures to be taken by solar heat collectors when solar heat is suddenly interrupted by clouds or when the direct solar radiation intensity decreases early in the morning or at dusk. Absent.

  Moreover, the molten salt which consists of 60% weight ratio of sodium nitrate and 40% weight ratio of potassium nitrate, which is widely adopted for solar heat heating medium, is less expensive than heat medium oil. However, since its solidification temperature is about 240 ° C, which is much higher than the ambient temperature of 15 ° C, it is always in contact with molten salt regardless of whether or not power is generated, molten salt storage tank, attached molten salt piping and accessories. It is necessary to always maintain the contact liquid surface temperature of a molten salt transfer pump or the like at about 250 ° C. or higher. Therefore, the temperature management equipment cost of the molten salt heating device, the molten salt storage device, and the transfer device is increased, and the operation cost of the equipment is increased.

  Furthermore, in the unlikely event that a device for circulating sodium nitrate-based molten salt or a system heat retention device fails, there is a risk that the emergency response cost for removing the solidified molten salt becomes enormous.

  In the present invention, in order to solve the above-mentioned problems, a mixed fluid obtained by mixing a small-sized solid-phase metal oxide and a gas-phase gas is used as a heat medium instead of a conventional liquid-phase synthetic oil or molten salt. Use as a medium. For example, a heat medium heating tube assembly has been devised in which a mixed heat medium in which a small mixture such as silicon dioxide or a stainless steel ball, which is the main component of sand, is mixed with air is heated by solar heat.

  In addition, a solar thermal power generation device has been devised that can use this mixture as a heat storage material and can perform heat storage power generation at low cost and practically compared to a conventional molten salt heat medium.

  Furthermore, a heat medium heating tube having a function of adjusting the heat medium moving speed and the moving amount when the mixed phase heat medium is heated by solar heat has been devised. Furthermore, an air heating apparatus was devised that heats air with a mixed phase heat medium heated to a high temperature.

  Furthermore, it is not a general steam turbine power generator that uses steam as a heat cycle material as a turbine device for driving a generator, but an air turbine generator that uses air heated and pressurized from this high-temperature heat medium to an intermediate temperature and medium pressure. Devised a solar thermal power generation device that generates electricity by driving.

Examples of suitable air turbine inlet air pressure and air temperature to be introduced into the air turbine in the present invention are an absolute pressure of about 6 kg / cm ² and about 600 ° C. The pressure and temperature of the air heating device for obtaining the air of this pressure and temperature and the heat medium heating device for producing a high-temperature heat medium from solar heat are determined by the inlet air pressure and temperature of the power generation air turbine. In other words, the pressure and temperature at the specification points of each related device are subordinately determined in consideration of pressure loss and temperature loss of various pipes and devices.

  According to this consideration, high-efficiency and economical solar power generation becomes possible. The above-described mixed phase heat medium is adopted as the heat medium to achieve economic efficiency. Furthermore, the versatility is improved by applying an air turbine power generation thermal cycle to a solar thermal power generation apparatus.

  In addition, an appropriate air turbine inlet pressure and temperature were selected, and a practical and economical thermal cycle was selected. The melting point of silicon dioxide, which is the main component of sand, is as high as about 1000 ° C., and even if the temperature is changed from room temperature 15 ° C. to 600 ° C., there is no concern that the heat medium dissolves and solidifies. This eliminates the need for measures against solidification of the heat medium and increases the reliability of the solar thermal power generation apparatus.

  Furthermore, since the present invention is an air turbine power generation system rather than a steam turbine power generation system, a large amount of cooling water for the steam turbine condenser is not required, and a solar thermal power generation apparatus can be installed even in a desert area where it is difficult to secure cooling water.

It is the schematic which shows the whole solar thermal power generation device which is embodiment of this invention. The general air temperature-entropy diagram shows the thermal cycle of the air turbine according to the present invention (compression → heating → expansion → cooling: (1) → (2), (2) → (3), (3) → (4) ▼, ▲ 4 ▼ → ▲ 1 ▼) It is the schematic which shows the whole heat-medium heating apparatus of embodiment of this invention. It is the schematic which shows the whole air heater of embodiment of this invention. It is the schematic which shows the partition plate support tube and partition plate which comprise the plate-shaped resistor provided in the mixed phase heat-medium heating tube of this invention. It is the schematic which shows the rod-shaped resistor provided in the inside of the mixed phase heat-medium heating tube of this invention, and a heat-medium heating tube.

  An embodiment of the solar thermal power generation apparatus of this device will be described. FIG. 1 is a schematic diagram showing the overall configuration of the solar thermal power generation apparatus.

  In the present embodiment, a small low-temperature heat medium 23 such as silicon dioxide, which is the main component of sand, is transferred as the solar heat medium, and the small low-temperature heat medium 23 is heated by the heat medium heating tube assembly 3. The heat medium heating tube assembly 3 has a structure like a heat transfer tube wall of a boiler furnace in which dozens to hundreds of heating tubes having an outer shape of about 20 mm to 50 mm are arranged. The heat medium heating tube described later may have an upright or inclined gradient. This assembly is a heat receiving wall made of a heat transfer tube that heats the low-temperature heat medium 23 that passes through the interior of the assembly by irradiating sunlight onto the outer surface of the assembly with the solar reflector 2. The material of the heat medium heating tube is the same as that of a generally used alloy steel tube for a boiler / heat exchanger. The material of the heating tube is determined by the operating temperature.

  The sunlight of the sun 1 is reflected by the sunlight reflecting mirror 2, and the low-temperature heat medium 23 flowing down in the heat medium heating tube assembly 3 is heated by solar heat. A heated high-temperature heat medium 29 is created, the high-temperature heat medium 29 is introduced into the air heater 21, and the air is heated through the air heating tube 27 to generate heated air heated to about 600 ° C. This air is sent to the air turbine 34, and the air turbine 34 is driven to rotate the air turbine generator 36 to generate electricity.

  The low temperature heat medium 23 stored in the heat medium low temperature lower tank 14 passes through the second heat medium transfer passage 26 driven by the first heat medium transfer device 13 and then is driven by the second heat medium transfer device 9. The third heat medium transfer passage 12 is lifted up to the first heat medium heating pipe upper communication passage 10.

  The low-temperature heat medium 23 passes through the first heat medium heating pipe upper communication passage 10 and the second heat medium heating pipe upper communication passage 11 and is distributed to the solar heat heating pipe upper header 8. The low-temperature heat medium 23 falls in the heat medium heating tube assembly 3 and reaches the solar heating tube lower pipe 4. Sunlight of the sun 1 is directed to the heat medium heating tube assembly 3 by the solar reflector 2, and the low temperature heat medium 23 is heated while being dropped and heated to the high temperature heat medium 29. The falling speed of the low-temperature heat medium 23 is determined by the shape, size, and weight of the heat medium and the shapes of various resistors installed inside the heating tube. The high temperature heat medium 29 is guided to the heat medium high temperature lower tank 6 via the lower connecting cylinder 5 and stored. The capacity of the heat medium high temperature lower tank 6 is determined in accordance with the heat storage time.

  The high temperature heat medium 29 leaves the heat medium high temperature lower tank 6 and reaches the fifth heat medium transfer path 19 by the fourth heat medium transfer device 16 and the fourth heat medium transfer path 18. Thereafter, the high-temperature heat medium 29 is lifted to the sixth heat medium transfer path 20 through the fifth heat medium transfer path 19 driven by the fifth heat medium transfer device 25 and transferred to the air heater upper chamber 17. . A bucket type belt conveyor or the like is suitable as a mechanism for lifting the solid heat medium vertically.

  The high-temperature heat medium 29 having a temperature of about 600 ° C. stored in the upper chamber 17 of the air heater moves while sliding in the air heating pipe 27 having an oblique gradient, exchanges heat, and heats the air.

  The air heating tube 27 provided in the air heater 21 is not provided with a resistor such as the partition plate 22 and the partition rod 63 installed in the heat medium heating tube described later, and the moving speed of the solid heat medium is set to the air heating tube 27. Set the slope of and adjust the sliding speed. The outer diameter of the air heating tube 27 is determined by the size and material of the solid heat medium, but is about 20 mm to about 50 mm. The heat energy of the high-temperature heat medium 29 is transferred from the heat medium to the air through the heat transfer tube of the circular tubular air heating tube 27. The required number of air heating tubes 27 is about several tens to several hundreds corresponding to the rated heat transfer amount.

  The cooled low temperature heat medium 23 exiting the air heating pipe 27 is collected in the air heater lower chamber 28, passes through the air heater lower chamber outlet passage 15, and is stored in the air heater lower temperature tank 14.

  The stored low-temperature heat medium 23 passes through the sixth heat medium transfer passage 26, is sent to the third heat medium transfer passage 12 by the first heat medium transfer device 13, and is again heated by collecting sunlight from the sun 1. The

  The air compressed by the air compressor 31 is compressed to a compression ratio of about 6, and the air whose temperature is raised to about 245 ° C. is further heated to high temperature air of about 600 ° C. The hot air heated to about 600 ° C. passes through the air turbine inlet pipe 33 and is sent to the air turbine 34 to drive the air turbine 34 and rotate the air turbine generator 36 to generate electricity. Exhaust air from the air turbine 34 passes through the air turbine exhaust duct 35 and returns to the atmosphere.

  When the sun is shaded by daytime clouds, the direct solar radiation intensity from the sun decreases. In such a case, the temperature of the high-temperature heat medium 29 is transmitted from the high-temperature heat medium temperature detector 68 to the heat medium transfer device drive control device 69, and the controller as described above indicates that the temperature of the high-temperature heat medium 29 has decreased below the set value. Detect. At that time, the high-temperature heat medium damper 70 is closed and the recirculation damper 71 is opened. The path of the high temperature heat medium 29 is switched from the fourth heat medium transfer passage 18 to the seventh heat medium transfer passage 61, and the flow of the high temperature heat medium 29 from the air heater 21 side to the heat medium heating tube assembly 3 side. The direction is switched to prevent a temperature drop in high temperature portions such as the heat medium heating tube assembly 3, the heat medium heating tube lower header 4, the lower connecting cylinder 5, the heat medium high temperature lower tank 6, and the like.

  Similarly, when the solar heat is cut off due to sudden rain or the like, the generator 36 is separated from the system, and the path of the high-temperature heat medium 29 is switched from the fourth heat medium transfer path 18 to the seventh heat medium transfer path 61. Perform circulating movement of high-temperature heat medium. By such an operation, the heat of the high-temperature heat medium 29 is sent to the heat medium assembly 3 that has started natural cooling, and the heat medium assembly 3 is warmed to enable a circulation standby operation in preparation for the next restart. .

  When the amount of circulation of the heat medium decreases due to a decrease in the amount of circulation of the heat medium, such as when some of the solid heat medium is gathered and fixed in the heat medium tank, the small solid heat stored in the solid particle tank 64 The medium is dispensed by a solid particle rotary valve 65. Then, the solid heat medium is supplied to the heat medium low temperature lower tank 14 via the solid particle transfer passage 66. Further, when the low-temperature heat medium 23 is discharged outside the system by an outside system (not shown) due to aging deterioration of the solid heat medium, it is replenished from the supply system for small solid heat medium.

According to the present invention, instead of the air compressor 31, a general air blower (not shown) is used to generate high temperature air using the heat medium heater 7 and the air heater 21 for general industries, not for power generation. Can supply. At this time, generally, the blower outlet pressure, which is generally used, is about 1 kg / cm ² or less, and the temperature is about 60 ° C. or less. If this air is sent to the compressor outlet pipe 32 of the air heater 21, it is sent to the inlet air pipe side of the air heater 21, so that high-temperature air of about 600 ° C. at maximum is obtained. The capacities of the heat medium heater 7 and the air heater 21 are determined according to the temperature and pressure conditions of the use destination. Thus, high-temperature air of about 100 ° C. or more and about 600 ° C. is obtained from solar heat corresponding to the required air temperature at the use destination.

  FIG. 2 is a diagram showing the air heat cycle of the air turbine of the present invention on the air temperature (unit: absolute temperature K) and entropy (kJ / (kg · K)) diagram. Since the standard atmospheric pressure and temperature are about 0.1 MPa absolute pressure and 288 K (= 15 ° C.), the inlet air state of the compressor 31 is indicated by point (1) in FIG. When an appropriate compression ratio is about 6, the compression temperature after compression is indicated by point (2) of about 245 ° C. (about 518 K). Similarly, after this compressed air is heated by solar heat, it rises to about 600 ° C. (= 875 K) and is indicated by point (3).

The state in which the heated air passes through the air turbine 34 to work and is expanded to atmospheric pressure is indicated by a point (4). The area surrounded by these four points indicates the amount of energy that can be extracted as work energy. Even if fossil fuel is not burned to produce high-temperature gas, the pressure is about 6 kg / cm ² and the temperature is about 600 ° C. It is shown that the power generation energy can be extracted from the solar thermal energy in the air thermal cycle. When the compression ratio is 6 and the efficiency of the compressor 31 is about 82%, the compressor outlet air temperature and pressure are about 518 K (= 245 ° C.) and the absolute pressure is about 0.6 MPa. Similarly, when the efficiency of the expanded air turbine 34 is about 88%, the air turbine exhaust temperature and pressure after expansion are about 560 K (= 287 ° C.) and the absolute pressure is about 0.01 MPa.

  3A is an overall schematic diagram of the heat medium heating device, and FIG. 3B is a plan arrangement example of a large number of solar reflectors 2 and the heat medium heating device installed around the heat medium heating device. The heat medium is collected in the upper portion 8 of the heat medium heating tube, and is heated by the collected solar heat while falling inside the heat medium heating tube assembly 3.

  The falling speed and direction of the heat medium are controlled by the structure, dimensions, and number of steps of the partition plate 22 provided in the heat medium heating pipe 7 shown in FIG. These are determined by the shape, solid weight, and material of the low-temperature heat medium 23. That is, the specification of the partition plate can be selected by a model experiment of the partition plate.

  The high temperature heat medium 29 gathered in the heat medium heating pipe lower pipe 4 passes through the lower connecting cylinder 5 and is temporarily stored in the heat medium high temperature lower tank 6. The amount to be stored is selected according to the amount of heat stored. The high temperature heat medium 29 passes through the fourth heat medium transfer passage 18 and is transferred to the air heater 21. The height of the heat medium heating device base 40 is determined in consideration of the gravity gradient of the high temperature heat medium 29 in the fourth heat medium transfer passage 18 and the transfer power from the fourth heat medium transfer device 16.

  In FIG. 5, (a) is the partition plate 22, (b) is the partition plate support tube 60, (c) is the partition plate inside the heat medium heating tube 7 in order to change the falling speed and direction of the small-sized low-temperature heat medium 23. An example is shown in which the support pipe 60 and the partition plates 22 supported by the support pipe 60 are arranged in three stages as four sheets. The number of plates 22 and the number of steps are selected according to the shape, size, and weight of the solid particles in the mixed phase heat medium. As an example, when a heavy stainless steel ball having a high solid-gas ratio is used as the solid phase heat medium, the speed of dropping in the heat medium heating tube 7 is increased, and therefore the number of partition plates 22 is increased. On the other hand, in the case of a small solid such as sand whose main component is silicon dioxide having a low solid-gas ratio, it is better to reduce the number of plates 22 or the number of steps.

  FIG. 6 shows that the low temperature heat medium 23 is introduced from the upper inlet of the heat medium heating pipe 7 and the partition rod 63 is arranged in six stages inside the heat medium heating pipe 7 in order to change the falling speed and direction of the small-sized low temperature heat medium 23. An example of installation is shown. The number and the number of the partition bars 63 are selected according to the size of the heating tube and the shape and size of the mixed phase heat medium. As an example, when a heavy stainless steel ball having a high solid-gas ratio is used as the solid phase heat medium, the speed of dropping in the heat medium heating tube 7 is increased, and thus the number of stages of the partition rod 63 is increased. On the other hand, in the case of a small solid such as sand mainly composed of silicon dioxide having a low solid-gas ratio, it is better to reduce the number of steps of the partition bar 63.

  The shape of the solid heat medium is basically a sphere, but may be a quadrilateral or triangular shape. The dimensions are about 1 mm, about 5 mm, and about 10 mm. A solid heat medium having a dimension of less than about 1 mm is not suitable because it is too small and the upright heat medium heating tube 7 may be clogged. In addition, a large heat medium exceeding about 10 mm is clogged in the gap between the upright heat medium heating tube 7 and the partition plate 22 or the partition rod 63, and the heat medium heating tube 7 is clogged, and the tube may be overheated and blown out without being cooled. Not suitable.

  As a selection condition for the solid heat medium, economy is an important selection criterion. The inner diameter of the heat medium heating tube 7 is at most about 15 mm to about 50 mm, which is preferable from the viewpoint of producing a large amount of suitable ceramic or metal solid particles at a low cost.

  Depending on the size of the heat medium heating tube 7 and the size of the solid heat medium, for example, an inclined heating tube other than upright can be applied as the heating tube. Furthermore, a solid heat medium in which solid particles typified by ceramic silicon dioxide and refractory metal solid particles typified by stainless steel are mixed is also applicable.

  FIG. 4 shows an overall schematic diagram of the air heater 21. The high-temperature heat medium 29 that has passed through the sixth heat medium transfer passage 20 flows into the air heater upper chamber 17 and heats the compressed air sent from the compressor outlet pipe 32 while passing through the air heating pipe 27. . The outer shape of the high-temperature heat medium 29 is basically a spherical shape. This flows down in the air heating pipe 27 and heats the air. The flow-down speed is determined by the outer shape and gradient of the air heating tube 27 and the outer size of the high-temperature heat medium 29. The heated hot air passes through the air turbine inlet pipe 33 and is sent to the air turbine 34.

  The low temperature heat medium 23 whose temperature has been lowered by heating the air gathers in the air heater lower chamber 28 and is stored in the heat medium low temperature lower tank 14 through the air heater lower chamber outlet passage 15.

  As described above, according to the present invention, a heat medium heating device that converts solar thermal energy into air energy economically and practically can be obtained. In addition, a solar thermal power generation apparatus that generates power by rotating the air turbine generator with this air energy is obtained. It can be used as a device that converts solar thermal energy into electric energy without burning fossil fuel, rather than a thermal power generation device that generates steam by burning fossil fuel and driving a steam turbine generator.

DESCRIPTION OF SYMBOLS 1 Sun 2 Sunlight reflector 3 Heat-medium heating pipe assembly 4 Heat-medium heating pipe lower pipe 5 Lower connection cylinder 6 Heat-medium high temperature lower tank 7 Heat-medium heating pipe 8 Heat-medium heating pipe upper pipe 9 Second heat medium Transfer device 10 First heat medium heating pipe upper communication passage 11 Second heat medium heating pipe upper communication passage 12 Third heat medium transfer passage 13 First heat medium transfer device 14 Heat medium low temperature lower tank 15 Air heater lower chamber outlet passage 16 Fourth heat medium transfer device 17 Air heater upper chamber 18 Fourth heat medium transfer passage 19 Fifth heat medium transfer passage 20 Sixth heat medium transfer passage 21 Air heater 22 Partition plate 23 Low temperature heat medium 25 Fifth heat medium Transfer device 26 Sixth heat medium transfer passage 27 Air heating pipe 28 Air heater lower chamber 29 High temperature heat medium 30 Compressor inlet duct 31 Air compressor 32 Compressor outlet pipe 33 Air turbine inlet pipe 34 Air turbine 35 Empty Air turbine exhaust duct 40 Heat medium heating device base 60 Partition plate support pipe 61 Seventh heat medium transfer passage 62 Fifth heat medium transfer device 65 Partition rod 64 Solid particle tank 65 Solid particle rotary valve 66 Solid particle transfer passage 67 Low temperature heat medium Temperature detector 68 High temperature heat medium temperature detector 69 Heat medium transfer device drive control device 70 High temperature heat medium damper 71 Recirculation damper

Claims (4)

  An assembly of heat medium heating tubes that pass a mixture of ceramic particles, metal oxides or refractory metal solid particles serving as a heat medium, and nitrogen gas or air and heat the mixture by solar heat; and A storage tank that stores the mixture that is heated by being connected to the assembly, and an air heater that heats the air that is supplied from the air compressor or the air blower by the heated mixture that is connected to the storage tank and is supplied from the storage tank. And a heating medium heating device.   2. The heating medium heating device according to claim 1, further comprising a damper mechanism that stops sending the mixture from the storage tank to the air heater and switches the mixture to the heating tube assembly.   The heating tube has a partition plate or a partition bar inside, and the temperature and amount of the mixture are increased by the speed and direction of the mixture being changed by the partition plate or the partition rod while the mixture falling in the heating tube is dropped. The heating medium heating device according to claim 1 or 2, wherein the heating medium heating device is adjusted.   An assembly of heating medium heating tubes in which a mixture of ceramic particles or metal oxide solid particles serving as a heating medium and nitrogen gas or air is passed inside and the mixture is heated by solar heat, and the heating tube assembly. A storage tank that stores the heated mixture, an air compressor that compresses air to a predetermined compression ratio, and the air compressor that is connected to the storage tank and supplied from the storage tank. A solar thermal power generation apparatus comprising: an air heater that heats compressed air supplied from an air heater; and an air turbine generator that is driven by the heated air supplied from the air heater.

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