A solid particle waste heat recovery system and method coupled with multi-stage heat storage

Abstract

The application provides a solid particle waste heat recovery system and method coupled with multi-stage heat storage, which comprises a fluidization recovery unit, an electric heating and power supply unit and an electric cooling and power supply unit. The fluidization unit comprises a fluidized bed main body, a gas-solid separator, a gas-liquid heat exchanger and an inorganic heat storage device. The electric heating and power supply unit comprises a first power generation unit, a first condenser, a first mixer, a heat supply return water pipeline and a heat supply feed water pipeline. The electric cooling and power supply unit comprises a generator, a gas-liquid separator, an organic heat storage device, a second power generation unit, a second condenser, a liquid-liquid heat exchanger and a second mixer. The generator is provided with a spraying pipe, a second heat exchange pipe and a heat storage pipe. The application combines the solid fluidization technology and the multi-stage heat storage technology, recovers the high-temperature solid particle waste heat with a wide particle size range according to the different particle sizes, sets the multi-stage heat storage devices matched with the waste heat temperature, realizes the efficient storage of the heat, and solves the stable output problem of the recovered heat.

Description

Technical Field

[0001] This invention belongs to the field of waste heat recovery and utilization technology, and relates to a solid particle waste heat recovery system and method coupled with multi-stage heat storage. Background Technology

[0002] With the continuous development of modern society and industry, industries such as metallurgy, building materials, chemicals, and power generate a large amount of high-temperature solid bulk materials, which exist in the form of calcined materials, industrial slag, sintered ore, etc. Due to their high temperature and abundant waste heat resources, direct discharge would not only fail to meet standards but also cause energy loss. How to achieve efficient recovery and utilization of the above-mentioned waste heat is of great significance to achieving the carbon emission target.

[0003] For waste heat recovery from high-temperature solid bulk materials, methods can be categorized into wet cooling and dry cooling, depending on the heat exchange medium. Wet cooling involves directly quenching molten slag with cold water, but it suffers from problems such as potential explosions, large equipment size, and high water consumption. Dry cooling uses cold gas for direct or indirect heat exchange with the molten slag, with the gas used for steam power generation or to supply hot water to boilers. Based on the particle size of the solid bulk materials, they can be classified as lumps or powders. High-temperature solid waste heat recovery technologies for either lumps or powders have been developed. For example, the use of recirculating heat exchangers in fluidized bed boiler slag coolers can recover preheated powdered slag.

[0004] Although the development of high-temperature solid waste heat recovery for individual block and powder materials is relatively mature, the application of waste heat recovery technology still faces problems for high-temperature solid bulk materials that contain both block and powder. Particles of different sizes have different residence times, heat transfer coefficients and heat transfer patterns. At the same time, particles of different sizes are prone to agglomeration, which affects the smooth and stable transport of materials. Therefore, new methods need to be sought for waste heat recovery of solid bulk materials with a wide particle size range.

[0005] CN 109442361A discloses an integrated system for efficient cascade recovery and utilization of waste heat from solid bulk materials. This integrated system includes a solid bulk material processing system and a waste heat power generation system. The solid bulk material processing system comprises a top-down bulk material separation system, a bulk material cooling system, and a bulk material collection system. The bulk material separation system separates the material into fine and coarse particles according to a set particle size. The bulk material cooling system includes a fine particle cooling box and a coarse particle cooling box arranged in parallel, a primary air heat exchanger, and a high-temperature hot water-bulk material heat exchanger connected to the waste heat power generation system. A secondary air inlet is provided at the bottom of the coarse particle cooling box, and a secondary air outlet is provided at the top. The high-temperature hot water-bulk material heat exchanger absorbs the waste heat from the fine particles and supplies energy to the waste heat power generation system, achieving efficient recovery of waste heat from bulk materials within different particle size ranges. However, due to the instability of solid bulk material flow rate, temperature, and other factors, fluctuations in the heat carried by the solid bulk material will occur, posing significant difficulties for obtaining stable heat for subsequent waste heat recovery. No solution to this problem is provided.

[0006] CN 108561202A discloses a low-temperature solid bulk material waste heat recovery power generation system to prevent solid particle erosion. The system includes a condenser, a dual-pressure turbine, a first-stage evaporator, a second-stage evaporator, a first-stage solid bulk material heat exchanger, and a second-stage solid bulk material heat exchanger. Using a dual-pressure turbine, the higher-temperature solid bulk material first passes through a hot water circulation system and the first-stage evaporator, heating the organic working fluid to a high-temperature, high-pressure state before entering the dual-pressure turbine for expansion and work. After one heat exchange, the lower-temperature solid bulk material and the waste heat from the hot water outlet of the first-stage evaporator are recovered through the second-stage evaporator to reheat the working fluid and drive work. This system achieves energy cascade utilization, mainly by utilizing the temperature difference before and after solid particle exposure, but it does not address waste heat recovery for solid particles with a wide particle size range.

[0007] In summary, for waste heat recovery from solid particles with a wide particle size range, it is necessary to carry out multi-stage separation and heat exchange based on the particle size characteristics of the solid particles, and to set up multi-stage heat storage devices that match the waste heat temperature in order to achieve efficient heat storage and stable output. Summary of the Invention

[0008] To address the problems existing in the prior art, the present invention aims to provide a solid particle waste heat recovery system and method coupled with multi-stage thermal storage. The system combines solid fluidization technology and multi-stage thermal storage technology to achieve graded recovery of waste heat from high-temperature solid particles with a wide particle size range according to different particle sizes. By setting up multi-stage thermal storage devices that match the waste heat temperature, the system achieves efficient heat storage and power generation applications, while solving the problem of stable output of recovered heat.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] On one hand, the present invention provides a solid particle waste heat recovery system coupled with multi-stage heat storage. The waste heat recovery system includes a fluidized bed recovery unit, a combined heat and power unit, and a combined cooling and power unit. The fluidized bed unit includes a fluidized bed body, a gas-solid separator, a gas-liquid heat exchanger, and an inorganic heat storage device. The gas-solid separator and the gas-liquid heat exchanger are each provided with at least one stage. The gas-solid separator and the gas-liquid heat exchanger are arranged alternately in sequence. The inorganic heat storage device has at least one more stage than the heat exchanger. The top of the fluidized bed body is provided with a solid particle inlet. The upper outlet of the fluidized bed body is connected to the first-stage gas-solid separator. The fluidized bed body is provided with a first heat exchange tube. The outlet and inlet of the first heat exchange tube are both connected to the first-stage inorganic heat storage device. The cold source outlet and cold source inlet of the gas-liquid heat exchanger are correspondingly connected to the inorganic heat storage devices after the first stage.

[0011] The combined heat and power unit includes a first power generation unit, a first condenser, and a first mixer. The inlet of the first mixer is connected to a heating return water pipeline, and the outlet of the first mixer is sequentially connected to the inlet of a multi-stage inorganic heat storage device. The outlet of the inorganic heat storage device is connected to a heating water supply pipeline and the first power generation unit. The gas outlet of the first power generation unit is sequentially connected to the first condenser and the first mixer.

[0012] The combined electric and cooling power supply unit includes a generator, a gas-liquid separator, an organic thermal storage device, a second power generation unit, a second condenser, a liquid-liquid heat exchanger, and a second mixer. The generator is equipped with a spray pipe, a second heat exchange pipe, and a thermal storage pipe. The spray pipe is located at the top inside the generator. The second heat exchange pipe and the thermal storage pipe are arranged alternately. The top outlet of the generator is connected to the inlet of the gas-liquid separator, and the bottom outlet of the generator is connected to the inlet of the second mixer. The liquid phase outlet of the gas-liquid separator is connected to the second mixer. The gas phase outlet of the gas-liquid separator is connected to the second power generation unit via the organic thermal storage device. The gas outlet of the second power generation unit is connected to the second mixer in sequence via the second condenser and the liquid-liquid heat exchanger. The heat source pipeline of the liquid-liquid heat exchanger is connected to the cooling return water pipeline and the cooling supply water pipeline, respectively. The outlet of the second mixer is connected to the spray pipe in the generator.

[0013] In this invention, the recovery of waste heat from high-temperature solid particles, especially those with a wide particle size range, requires graded recovery based on particle size, simultaneously recovering waste heat from different stages. This invention combines solid particle fluidization technology with multi-stage heat storage technology through the setup of fluidized bed recovery, combined power generation and cooling units. Fluidized beds and gas-solid separators are used to grade and separate solid particles with a wide particle size range, and the gases obtained after each stage of separation undergo heat exchange, storing the heat in a heat storage device. This involves setting up a multi-stage heat storage device matched to the waste heat temperature, achieving efficient heat storage and deep tiered utilization. The stored heat can then be used for power generation, heating, and cooling, offering diverse applications and solving the problem of stable output of recovered heat. The system has a reasonable structural design, stable operation, low cost, and wide application range.

[0014] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The technical objectives and beneficial effects of the present invention can be better achieved and realized through the following technical solutions.

[0015] As a preferred embodiment of the present invention, the fluidized bed body is provided with an air inlet at the bottom and a coarse particle outlet at the bottom.

[0016] Preferably, both the gas-solid separator and the gas-liquid heat exchanger are provided in two stages, namely a first gas-solid separator, a first gas-liquid heat exchanger, a second gas-solid separator, and a second gas-liquid heat exchanger connected in sequence, and the lower part of the first gas-solid separator and the second gas-solid separator are provided with fine particle outlets.

[0017] In this invention, the material inlet of the first gas-solid separator is connected to the fluidized bed body, the gas outlet of the first gas-solid separator is connected to the hot-side inlet of the first gas-liquid heat exchanger, the hot-side outlet of the first gas-liquid heat exchanger is connected to the material inlet of the second gas-solid separator, the particle outlet of the second gas-solid separator is connected to the particle outlet of the first gas-solid separator, and the gas outlet of the second gas-solid separator is connected to the hot-side channel inlet of the second gas-liquid heat exchanger.

[0018] Preferably, the gas-solid separator includes any one or a combination of at least two of the following: a cyclone separator, an inertial separator, or a settling separator. Typical but non-limiting examples of such combinations include: a combination of a cyclone separator and an inertial separator, a combination of an inertial separator and a settling separator, and a combination of a cyclone separator, an inertial separator, and a settling separator.

[0019] Preferably, the first heat exchange tube includes a first heat exchange coil.

[0020] Preferably, in the inorganic heat storage device, the first inorganic heat storage device is connected to the first heat exchange tube, the second inorganic heat storage device is connected to the cold source outlet and cold source inlet of the first gas-liquid heat exchanger, and the third inorganic heat storage device is connected to the cold source outlet and cold source inlet of the second gas-liquid heat exchanger.

[0021] Preferably, a circulating pump is provided on the connecting pipelines between the first heat exchange tube and the first inorganic heat storage device, the first gas-liquid heat exchanger and the second inorganic heat storage device, and the second gas-liquid heat exchanger and the third inorganic heat storage device.

[0022] In this invention, the outlet end of the first heat exchange tube is connected to the hot-side pipeline of the first inorganic heat storage device via a circulation pump, and then connected back to the inlet end of the first heat exchange tube; the outlet end of the cold-side pipeline of the first gas-liquid heat exchanger is connected to the hot-side pipeline of the second inorganic heat storage device via a circulation pump, and then connected back to the inlet end of the cold-side pipeline of the first gas-liquid heat exchanger; the outlet end of the cold-side pipeline of the second gas-liquid heat exchanger is connected to the hot-side pipeline of the third inorganic heat storage device via a circulation pump, and then connected back to the inlet end of the cold-side pipeline of the second gas-liquid heat exchanger.

[0023] Preferably, the first inorganic thermal storage device is filled with an inorganic carbonate composite material.

[0024] Preferably, the second inorganic thermal storage device is filled with an alloy-type composite material.

[0025] Preferably, the third inorganic thermal storage device is filled with a composite material of alkali metal salts and alkali metal hydroxides.

[0026] As a preferred embodiment of the present invention, the fluidized bed recovery unit further includes a blower, the outlet of which is connected to the air inlet of the fluidized bed body.

[0027] Preferably, the fluidized bed recovery unit further includes a first concave concentrating mirror and a fourth inorganic heat storage device. One end of the heat exchange pipe of the fourth inorganic heat storage device is connected to the outlet of the blower, and the other end is connected to the air inlet of the fluidized bed body. The first concave concentrating mirror focuses sunlight onto the heated surface of the fourth inorganic heat storage device.

[0028] Preferably, the fourth inorganic thermal storage device is filled with an inorganic nitrate composite material.

[0029] As a preferred embodiment of the present invention, the first power generation unit includes a first turbine and a first generator, the first turbine is connected to the shaft of the first generator, and the exhaust port of the first turbine is connected to the inlet of the first condenser.

[0030] In this invention, the first turbine and the first generator are connected by a coupling.

[0031] Preferably, the first turbine is provided with a steam extraction port, which is connected to the inlet of the first mixer.

[0032] In this invention, the steam extracted from the steam extraction port of the first turbine is used to heat the fluid in the first mixer.

[0033] Preferably, a circulation pump is independently provided on the connecting pipes of the first condenser and the first mixer, as well as on the connecting pipes of the first mixer and the inorganic heat storage device.

[0034] Preferably, the outlet of the first mixer is sequentially connected to the third inorganic thermal storage device, the second inorganic thermal storage device, and the first inorganic thermal storage device.

[0035] Preferably, the outlet of the first mixer is first connected to the inlet of the cold-side pipeline of the third inorganic thermal storage device. The outlet of the cold-side pipeline of the third inorganic thermal storage device is divided into two branches: one branch is connected to the heating water supply pipeline, and the other branch is connected to the inlet of the cold-side pipeline of the second inorganic thermal storage device. The outlet of the cold-side pipeline of the second inorganic thermal storage device is divided into two branches: one branch is connected to the inlet of the cold-side pipeline of the first inorganic thermal storage device, and the other branch is connected to the steam injection port of the first turbine. The outlet of the cold-side pipeline of the first inorganic thermal storage device is connected to the main steam port of the first turbine.

[0036] As a preferred embodiment of the present invention, the heat storage tubes in the generator are several horizontally placed circular metal tubes, preferably circular stainless steel tubes.

[0037] Preferably, the heat storage tubes are arranged in a staggered and / or parallel arrangement in the vertical direction.

[0038] Preferably, the heat storage tube is filled with a first organic heat storage material, which includes sugar alcohols, preferably erythritol.

[0039] Preferably, the second heat exchange tube is divided into two parts, located at the upper and lower parts of the generator, and a heat storage tube is provided between the two parts of the second heat exchange tube, located in the middle of the generator.

[0040] Preferably, the gas outlet of the second gas-liquid heat exchanger is connected to the inlet of the second heat exchange tube, and the outlet of the second heat exchange tube is also connected to a dust removal and purification device.

[0041] Preferably, the organic thermal storage device is equipped with a matching second concave concentrator, which focuses sunlight onto the heated surface of the organic thermal storage device.

[0042] Preferably, the organic heat storage device is filled with a second organic heat storage material, which includes sugar alcohols, preferably mannitol.

[0043] Preferably, the second power generation unit includes a second turbine and a second generator, the second turbine is connected to the shaft of the second generator, and the exhaust port of the second turbine is connected to the inlet of the second condenser.

[0044] In this invention, the second turbine and the second generator are connected by a coupling.

[0045] Preferably, a circulation pump is provided on the connecting pipe between the second condenser and the liquid-liquid heat exchanger.

[0046] Preferably, the liquid-liquid heat exchanger includes a first liquid-liquid heat exchanger and a second liquid-liquid heat exchanger, and the outlet of the second condenser is connected to the inlet of the second mixer via the cold side pipeline of the first liquid-liquid heat exchanger, the cold side pipeline of the second liquid-liquid heat exchanger, and the hot side pipeline of the first liquid-liquid heat exchanger in sequence.

[0047] Preferably, the hot-side piping of the second liquid-liquid heat exchanger is connected to the cooling return water piping and the cooling supply water piping.

[0048] Preferably, a circulation pump is provided on the connecting pipe between the second mixer and the spray pipe in the generator.

[0049] Preferably, the combined electric and cooling power supply unit further includes a third liquid-liquid heat exchanger, the outlet of the second mixer is connected to the spray pipe via the cold side pipe of the third liquid-liquid heat exchanger, and the bottom outlet of the generator is connected to the inlet of the second mixer via the hot side pipe of the third liquid-liquid heat exchanger.

[0050] On the other hand, the present invention provides a method for recovering waste heat from solid particles using the above-described system with coupled multi-stage heat storage, the method comprising the following steps:

[0051] (1) Solid particles and gas are subjected to countercurrent fluidized heat exchange in the fluidized bed body. After the gas is heated, it exchanges heat with the first heat exchange tube and carries the fine particles away. It passes through at least one gas-solid separation and gas-liquid heat exchange in sequence. After the coarse particles settle, they are discharged from the bottom of the fluidized bed body. The heat carried by the fluid after heat exchange through the first heat exchange tube and gas-liquid heat exchange is stored in a multi-stage inorganic heat storage device.

[0052] (2) After the heating return water is heated by the cold side pipeline of the inorganic heat storage device described in step (1), it is divided into two streams. One stream provides heating water, and the other stream generates steam for steam power generation. The exhaust steam after power generation is condensed and mixed with the heating return water.

[0053] (3) Step (1) The gas after gas-liquid heat exchange enters the second heat exchange tube and heat storage tube for heat exchange. At the same time, concentrated ammonia water solution is sprayed out through the spray pipe from top to bottom through the surface of the second heat exchange tube and heat storage tube. After some ammonia water evaporates, it is separated into two streams by gas-liquid separation. One stream is ammonia vapor and the other stream is dilute ammonia water solution. The ammonia vapor is heated by the organic heat storage device and then used for steam power generation. The exhaust steam after power generation is condensed, liquid-liquid heat exchanged and mixed with the dilute ammonia water solution obtained after gas-liquid separation and the part of concentrated ammonia water solution that has not evaporated after heat exchange. After mixing, concentrated ammonia water solution is obtained again and enters the spray pipe.

[0054] As a preferred technical solution of the present invention, the particle size range of the solid particles in step (1) is 0.1 to 15 mm, such as 0.1 mm, 0.5 mm, 1 mm, 2 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 14 mm or 15 mm, etc., but not limited to the listed values, other unlisted values ​​within this range are also applicable; the temperature is 1200 to 1600℃, such as 1200℃, 1250℃, 1300℃, 1350℃, 1400℃, 1450℃, 1500℃, 1550℃ or 1600℃, etc., but not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0055] Preferably, the gas in step (1) includes preheated air, which is introduced by a blower and heated to 180-280°C when passing through the fourth inorganic heat storage device, such as 180°C, 200°C, 220°C, 240°C, 260°C or 280°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0056] Preferably, the fourth inorganic thermal storage device is filled with an inorganic nitrate composite material, preferably an alkali metal nitrate, such as sodium nitrate and potassium nitrate.

[0057] Preferably, the fourth inorganic thermal energy storage device stores the collected solar energy in the form of thermal energy, and its internal temperature is maintained at 200-300°C, such as 200°C, 220°C, 240°C, 250°C, 260°C, 280°C or 300°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0058] Preferably, during the gas rise process in step (1), the gas passes through the first heat exchange tube, and the heat exchange fluid in the first heat exchange tube is heated to 650-850°C, such as 650°C, 675°C, 700°C, 725°C, 750°C, 775°C, 800°C, 825°C or 850°C, but not limited to the listed values. Other unlisted values ​​within this range are also applicable. The heat exchange fluid in the first heat exchange tube includes any one or at least two alloys of liquid metal gallium, indium or tin. The alloys include: alloys of gallium and indium, alloys of indium and tin, alloys of gallium, indium and tin, etc.

[0059] Preferably, the heat exchange fluid in the first heat exchange tube flows through the first inorganic heat storage device, storing heat in the first inorganic heat storage device, and its internal temperature is maintained at 600-800℃, such as 600℃, 620℃, 650℃, 680℃, 700℃, 720℃, 750℃, 780℃ or 800℃, etc., but not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0060] Preferably, the first inorganic thermal storage device is filled with an inorganic carbonate composite material, preferably an alkali metal carbonate and / or an alkaline earth metal carbonate, such as a composite material of sodium carbonate and calcium carbonate, a composite material of potassium carbonate and magnesium carbonate, a composite material of sodium carbonate and potassium carbonate, etc.; when sodium carbonate and calcium carbonate are selected in a mass ratio of 1:1, the phase change temperature is 710℃.

[0061] Preferably, the solid particles have a particle size range of 5 to 15 mm, such as 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 14 mm, or 15 mm, and are discharged from the lower outlet of the fluidized bed body. The discharge temperature is 120 to 140°C, such as 120°C, 122°C, 124°C, 126°C, 128°C, 130°C, 132°C, 134°C, 136°C, 138°C, or 140°C, but is not limited to the listed values. Other unlisted values ​​within their respective ranges are also applicable.

[0062] Preferably, the solid particles have a particle size range of 0.1 to 5 mm, such as 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm, and exit with the gas from the upper outlet of the fluidized bed body. At this time, the temperature of the gas is 680 to 700°C, such as 680°C, 682°C, 684°C, 686°C, 688°C, 690°C, 692°C, 694°C, 696°C, 698°C, or 700°C, but is not limited to the listed values. Other unlisted values ​​within their respective ranges are also applicable.

[0063] Preferably, the gas-solid separation and gas-liquid heat exchange in step (1) are performed twice, and the operation sequence is as follows: first gas-solid separation, first gas-liquid heat exchange, second gas-solid separation, and second gas-liquid heat exchange.

[0064] Preferably, the gas-solid separation includes any one or a combination of at least two of cyclone separation, inertial separation, and sedimentation separation. Typical but non-limiting examples of such combinations include: a combination of cyclone separation and inertial separation, a combination of inertial separation and sedimentation separation, and a combination of cyclone separation, inertial separation, and sedimentation separation, etc.

[0065] Preferably, the particle size of the solid particles separated after the first gas-solid separation is 2-5 mm, such as 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm, etc., and the particle size of the solid particles separated after the second gas-solid separation is 0.1-2 mm, such as 0.1 mm, 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm or 2 mm, etc., but not limited to the listed values, other unlisted values ​​within their respective ranges are also applicable.

[0066] Preferably, the gas temperature after the primary gas-liquid heat exchange is reduced to 420–460°C, such as 420°C, 425°C, 430°C, 435°C, 440°C, 445°C, 450°C, 455°C, or 460°C, and the gas temperature after the secondary gas-liquid heat exchange is reduced to 220–250°C, such as 220°C, 225°C, 230°C, 235°C, 240°C, 245°C, or 250°C, but is not limited to the listed values; other unlisted values ​​within their respective ranges are also applicable.

[0067] Preferably, the heat exchange fluids for the primary gas-liquid heat exchange and the secondary gas-liquid heat exchange independently include heat transfer oil.

[0068] Preferably, the heat exchange fluid after the first gas-liquid heat exchange flows through the second inorganic heat storage device, where the heat is stored and the internal temperature is maintained at 300-600°C, such as 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, or 600°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0069] Preferably, the second inorganic thermal storage device is filled with an alloy composite material, preferably a combination of at least two of aluminum, copper, or silicon, such as a combination of copper and silicon, a combination of aluminum and silicon, or a combination of aluminum, copper, and silicon. For example, the mass ratio of aluminum, copper, and silicon can be selected as 68.5:26.5:5, in which case the phase transition temperature is 525°C.

[0070] Preferably, the heat exchange fluid after the secondary gas-liquid heat exchange flows through the third inorganic heat storage device, where the heat is stored and the internal temperature is maintained at 200-300°C, such as 200°C, 220°C, 240°C, 250°C, 260°C, 280°C, or 300°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0071] Preferably, the third inorganic thermal storage device is filled with a composite material of alkali metal salts and alkali metal hydroxides, such as sodium carbonate and sodium hydroxide, potassium carbonate and potassium hydroxide, sodium sulfate and sodium hydroxide, etc. When the mass ratio of sodium carbonate to sodium hydroxide is selected as 17:83, the phase change temperature is 285°C.

[0072] As a preferred technical solution of the present invention, the temperature of the heating return water in step (2) is 65-75℃, such as 65℃, 66℃, 67℃, 68℃, 69℃, 70℃, 72℃, 74℃ or 75℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0073] Preferably, the heating return water in step (2) flows sequentially through the cold side pipelines of the third inorganic heat storage device, the second inorganic heat storage device, and the first inorganic heat storage device for heating.

[0074] Preferably, the temperature of the heating return water rises to 90-98°C after flowing through the cold side pipeline of the third inorganic thermal storage device, such as 90°C, 92°C, 94°C, 95°C, 96°C or 98°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable. The water is divided into two streams, one as heating supply water and the other entering the cold side pipeline of the second inorganic thermal storage device.

[0075] Preferably, the feedwater flowing through the cold-side pipeline of the second inorganic thermal storage device is transformed from liquid to saturated steam at a temperature of 273–283°C, such as 273°C, 275°C, 277°C, 279°C, 280°C, 281°C, or 283°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable. The feedwater is then divided into two streams, one entering the steam inlet of the first turbine and the other entering the cold-side pipeline of the first inorganic thermal storage device.

[0076] Preferably, the saturated steam flowing through the cold-side pipeline of the first inorganic thermal storage device is converted into superheated steam at a temperature of 535-545°C, such as 535°C, 536°C, 537°C, 538°C, 539°C, 540°C, 542°C, 543°C, 544°C, or 545°C, but not limited to the listed values. Other unlisted values ​​within this range are also applicable, and the steam enters the main steam port of the first turbine.

[0077] Preferably, the steam entering the main steam inlet and the make-up steam inlet of the first turbine drives the first turbine to rotate and do work, thereby driving the first generator to generate electricity. After doing work, the temperature of the exhaust steam drops to 52-56°C, such as 52°C, 52.5°C, 53°C, 53.5°C, 54°C, 54.5°C, 55°C, 55.5°C, or 56°C, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0078] Preferably, the exhaust steam after work is condensed to 52-56°C to form a liquid phase, such as 52°C, 52.5°C, 53°C, 53.5°C, 54°C, 54.5°C, 55°C, 55.5°C, or 56°C, but not limited to the listed values. Other unlisted values ​​within this range are also applicable. The liquid is mixed with the heating return water and heated by the steam extracted from the steam extraction port of the first turbine. The resulting mixed fluid is then circulated into the inorganic heat storage device.

[0079] In this invention, the exhaust steam obtained after steam does work undergoes a phase change during condensation, releasing heat, while its temperature remains essentially unchanged.

[0080] As a preferred technical solution of the present invention, the gas after gas-liquid heat exchange in step (3) is cooled to 85-95°C after passing through the second heat exchange tube, for example, 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C or 95°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable. After purification and dust removal, the gas is discharged into the air.

[0081] Preferably, the heat storage tube in step (3) is filled with a first organic heat storage material, which includes sugar alcohols, preferably erythritol, and has a phase change temperature of 118°C.

[0082] Preferably, the temperature of the first organic heat storage material in the heat storage pipe is maintained at 110-150°C, such as 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C or 150°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0083] Preferably, the concentrated ammonia solution in step (3) is sprayed into the spray pipe after being atomized by the nozzle. The concentration of the concentrated ammonia solution is 25-30 wt%, such as 25 wt%, 25.5 wt%, 26 wt%, 26.5 wt%, 27 wt%, 27.5 wt%, 28 wt%, 28.5 wt%, 29 wt%, 29.5 wt%, or 30 wt%, but not limited to the listed values. Other unlisted values ​​within this range are also applicable. The temperature is 85-90℃, such as 85℃, 85.5℃, 86℃, 86.5℃, 87℃, 87.5℃, 88℃, 88.5℃, 89℃, 89.5℃, or 90℃, but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0084] Preferably, during the downward movement of the concentrated ammonia solution, some ammonia and water evaporate, and the resulting gas-liquid mixture enters the gas-liquid separator.

[0085] Preferably, the temperature for gas-liquid separation in step (3) is 90–95°C, such as 90°C, 90.5°C, 91°C, 91.5°C, 92°C, 92.5°C, 93°C, 93.5°C, 94°C, 94.5°C, or 95°C, but not limited to the listed values; other unlisted values ​​within this range are also applicable. The pressure is 0.08–0.1 MPa, such as 0.08 MPa, 0.082 MPa, 0.084 MPa, 0.086 MPa, 0.088 MPa, 0.09 MPa, 0.092 MPa, 0.094 MPa, 0.096 MPa, 0.098 MPa, or 0.10 MPa, but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0086] Preferably, the ammonia vapor in step (3) is heated and pressurized by the heat stored in the organic heat storage device, and the temperature reaches 160-180℃, such as 160℃, 162℃, 164℃, 166℃, 168℃, 170℃, 172℃, 174℃, 176℃, 178℃ or 180℃, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable; the pressure reaches 0.6-0.8MPa, such as 0.6MPa, 0.62MPa, 0.64MPa, 0.66MPa, 0.68MPa, 0.7MPa, 0.72MPa, 0.74MPa, 0.76MPa, 0.78MPa or 0.8MPa, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable, thus forming superheated ammonia vapor.

[0087] Preferably, the organic heat storage device is filled with a second organic heat storage material, which includes sugar alcohols, preferably mannitol, and has a phase change temperature of 167°C.

[0088] Preferably, the organic thermal storage device stores the collected solar energy in the form of thermal energy, and its internal temperature is maintained at 150-200°C, such as 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 190°C or 200°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0089] Preferably, the dilute ammonia solution obtained by gas-liquid separation in step (3) is a first dilute ammonia solution with a concentration of 8.5 to 12.5 wt%, such as 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 10.5 wt%, 11 wt%, 11.5 wt%, 12 wt%, or 12.5 wt%, but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0090] Preferably, the portion of the concentrated ammonia solution that does not evaporate after heat exchange in step (3) is a second dilute ammonia solution that flows out from the bottom of the generator. Its concentration is 8.5 to 12.5 wt%, for example, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 10.5 wt%, 11 wt%, 11.5 wt%, 12 wt%, or 12.5 wt%, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0091] As a preferred technical solution of the present invention, in step (3), the ammonia vapor enters the second turbine to expand and do work, driving the second generator to generate electricity. The temperature of the exhaust steam after doing work drops to -25 to -15℃, for example -25℃, -24℃, -23℃, -22℃, -21℃, -20℃, -19℃, -18℃, -17℃, -16℃ or -15℃, etc., but not limited to the listed values. Other unlisted values ​​within this range are also applicable. The pressure drops to 0.15 to 0.24MPa, for example 0.15MPa, 0.16MPa, 0.17MPa, 0.18MPa, 0.19MPa, 0.20MPa, 0.21MPa, 0.22MPa, 0.23MPa or 0.24MPa, etc., but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0092] Preferably, the exhaust steam after work is condensed to -30 to -20°C to form a gas-liquid mixture, such as -30°C, -29°C, -28°C, -27°C, -26°C, -25°C, -24°C, -23°C, -22°C, -21°C, or -20°C, and exchanges heat with the supply cooling water. The temperature of the supply cooling water is reduced from 10 to 15°C, such as 10°C, 11°C, 12°C, 13°C, 14°C, or 15°C, to 4 to 10°C, such as 4°C, 5°C, 6°C, 7°C, 8°C, 9°C, or 10°C; however, it is not limited to the listed values, and other unlisted values ​​within their respective ranges are also applicable.

[0093] Preferably, the condensed gas-liquid mixture undergoes a first liquid-liquid heat exchange, then a heat exchange with the cooling water, and then a second liquid-liquid heat exchange. The first and second liquid-liquid heat exchanges are heat exchanges in the same heat exchanger, with the gas-liquid mixture serving as the cold source and heat source, respectively.

[0094] Preferably, in step (3), the multiple fluids are mixed and heated before entering the spray pipe, and the fluid that exchanges heat with it is the second dilute ammonia solution flowing out from the bottom of the generator.

[0095] Compared with the prior art, the present invention has the following beneficial effects:

[0096] (1) The system described in this invention combines solid particle fluidization technology with multi-stage heat storage technology by setting up units such as fluidized recovery, combined power and heat supply and combined power and cooling. It can realize graded recovery of waste heat of high temperature solid particles with a wide particle size range according to different particle sizes, and realize efficient heat storage and deep cascade utilization by setting up multi-stage heat storage devices that match the waste heat temperature.

[0097] (2) The system described in this invention generates electricity, heats and cools the stored heat, with diverse applications, and solves the problem of stable output of recovered heat;

[0098] (3) In this invention, some of the thermal storage devices utilize solar energy to collect heat, thereby increasing the temperature and quality of the corresponding working fluid, so as to enhance the energy conversion efficiency and overall thermal utilization rate of the whole system.

[0099] (4) The system structure of the present invention is reasonably designed, operates stably, has low cost, and has a wide range of applications. Attached Figure Description

[0100] Figure 1 This is a schematic diagram of the structure of the solid particle waste heat recovery system coupled with multi-stage heat storage provided in Embodiment 1 of the present invention;

[0101] Among them, 1-fluidized bed body, 1-1-first heat exchange tube, 2-1-first gas-solid separator, 2-2-second gas-solid separator, 3-1-first gas-liquid heat exchanger, 3-2-second gas-liquid heat exchanger, 4-1-first inorganic heat storage device, 4-2-second inorganic heat storage device, 4-3-third inorganic heat storage device, 4-4-fourth inorganic heat storage device, 5-blower, 6-first concave condenser mirror, 7-1-first turbine, 7-2-second turbine, 8-1-first generator, 8 -2-Second generator, 9-1-First condenser, 9-2-Second condenser, 10-1-First mixer, 10-2-Second mixer, 11-Generator, 11-1-Spray pipe, 11-2-Second heat exchange pipe, 11-3-Heat storage pipe, 12-Gas-liquid separator, 13-Organic heat storage device, 14-Dust removal and purification device, 15-Second concave condenser mirror, 16-1-First liquid-liquid heat exchanger, 16-2-Second liquid-liquid heat exchanger, 16-3-Third liquid-liquid heat exchanger. Detailed Implementation

[0102] To better illustrate the present invention and facilitate understanding of its technical solutions, the present invention is further described in detail below. However, the following embodiments are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0103] The following are typical but non-limiting embodiments of the present invention:

[0104] Example 1:

[0105] This embodiment provides a solid particle waste heat recovery system coupled with multi-stage heat storage. A schematic diagram of the waste heat recovery system is shown below. Figure 1As shown, the system includes a fluidized bed recovery unit, a combined heat and power unit, and a combined cooling and power unit. The fluidized bed unit includes a fluidized bed body 1, a gas-solid separator, a gas-liquid heat exchanger, and an inorganic heat storage device. The gas-solid separator and the gas-liquid heat exchanger are both provided in two stages, and the gas-solid separator and the gas-liquid heat exchanger are arranged alternately in sequence. The inorganic heat storage device has two more stages than the heat exchanger. The top of the fluidized bed body 1 is provided with a solid particle inlet, and the upper outlet of the fluidized bed body 1 is connected to the first-stage gas-solid separator. The fluidized bed body 1 is provided with a first heat exchange tube 1-1, and the outlet and inlet of the first heat exchange tube 1-1 are both connected to the first-stage inorganic heat storage device. The cold source outlet and cold source inlet of the gas-liquid heat exchanger are correspondingly connected to the inorganic heat storage devices after the first stage.

[0106] The combined heat and power unit includes a first power generation unit, a first condenser 9-1, and a first mixer 10-1. The inlet of the first mixer 10-1 is connected to a heating return water pipeline, and the outlet of the first mixer 10-1 is sequentially connected to the inlet of a multi-stage inorganic heat storage device. The outlet of the inorganic heat storage device is connected to a heating water supply pipeline and the first power generation unit. The gas outlet of the first power generation unit is sequentially connected to the first condenser 9-1 and the first mixer 10-1.

[0107] The combined power supply unit includes a generator 11, a gas-liquid separator 12, an organic thermal storage device 13, a second power generation unit, a second condenser 9-2, a liquid-liquid heat exchanger, and a second mixer 10-2. The generator 11 is equipped with a spray pipe 11-1, a second heat exchange pipe 11-2, and a thermal storage pipe 11-3. The spray pipe 11-1 is located at the top inside the generator 11. The second heat exchange pipe 11-2 and the thermal storage pipe 11-3 are alternately arranged. The top outlet of the generator 11 is connected to the inlet of the gas-liquid separator 12. The bottom outlet of the gas-liquid separator 12 is connected to the inlet of the second mixer 10-2. The liquid phase outlet of the gas-liquid separator 12 is connected to the second mixer 10-2. The gas phase outlet of the gas-liquid separator 12 is connected to the second power generation unit via the organic heat storage device 13. The gas outlet of the second power generation unit is connected to the second mixer 10-2 via the second condenser 9-2 and the liquid-liquid heat exchanger in sequence. The heat source pipeline of the liquid-liquid heat exchanger is connected to the cooling return water pipeline and the cooling supply water pipeline respectively. The outlet of the second mixer 10-2 is connected to the spray pipe in the generator 11.

[0108] The fluidized bed body 1 has an air inlet at the bottom and a coarse particle outlet at the bottom.

[0109] Both the gas-solid separator and the gas-liquid heat exchanger are provided in two stages, namely, a first gas-solid separator 2-1, a first gas-liquid heat exchanger 3-1, a second gas-solid separator 2-2, and a second gas-liquid heat exchanger 3-2 connected in sequence. The lower part of the first gas-solid separator 2-1 and the second gas-solid separator 2-2 are provided with fine particle outlets.

[0110] All gas-solid separators mentioned are cyclone separators.

[0111] In the inorganic heat storage device, the first inorganic heat storage device 4-1 is connected to the first heat exchange tube, the second inorganic heat storage device 4-2 is connected to the cold source outlet and cold source inlet of the first gas-liquid heat exchanger 3-1, and the third inorganic heat storage device 4-3 is connected to the cold source outlet and cold source inlet of the second gas-liquid heat exchanger 3-2.

[0112] A circulation pump is provided on the connecting pipelines of the first heat exchange tube 1-1 and the first inorganic heat storage device 4-1, the first gas-liquid heat exchanger 3-1 and the second inorganic heat storage device 4-2, and the second gas-liquid heat exchanger 3-2 and the third inorganic heat storage device 4-3.

[0113] The first inorganic heat storage device 4-1 is filled with an inorganic carbonate composite material; the second inorganic heat storage device 4-2 is filled with an alloy composite material; and the third inorganic heat storage device 4-3 is filled with a composite material of alkali metal salts and alkali metal hydroxides.

[0114] The fluidized bed recovery unit also includes a blower 5, the outlet of which is connected to the air inlet of the fluidized bed body 1.

[0115] The fluidized bed recovery unit also includes a first concave concentrating mirror 6 and a fourth inorganic heat storage device 4-4. One end of the heat exchange pipe of the fourth inorganic heat storage device 4-4 is connected to the outlet of the blower 5, and the other end is connected to the air inlet of the fluidized bed body 1. The first concave concentrating mirror 6 focuses sunlight onto the heated surface of the fourth inorganic heat storage device 4-4.

[0116] The fourth inorganic thermal storage device 4-4 is filled with inorganic nitrate composite material.

[0117] The first power generation unit includes a first turbine 7-1 and a first generator 8-1. The first turbine 7-1 is shaft-connected to the first generator 8-1, and the exhaust port of the first turbine 7-1 is connected to the inlet of the first condenser 9-1.

[0118] The first turbine 7-1 is provided with a steam extraction port, which is connected to the inlet of the first mixer 10-1.

[0119] A circulation pump is provided on the connecting pipes of the first condenser 9-1 and the first mixer 10-1, as well as on the connecting pipes of the first mixer 10-1 and the inorganic heat storage device.

[0120] The outlet of the first mixer 10-1 is sequentially connected to the third inorganic heat storage device 4-3, the second inorganic heat storage device 4-2, and the first inorganic heat storage device 4-1.

[0121] The outlet of the first mixer 10-1 is first connected to the inlet of the cold side pipeline of the third inorganic heat storage device 4-3. The outlet of the cold side pipeline of the third inorganic heat storage device 4-3 is divided into two branches, one of which is connected to the heating water supply pipeline and the other of which is connected to the inlet of the cold side pipeline of the second inorganic heat storage device 4-2. The outlet of the cold side pipeline of the second inorganic heat storage device 4-2 is divided into two branches, one of which is connected to the inlet of the cold side pipeline of the first inorganic heat storage device 4-1 and the other of which is connected to the steam injection port of the first turbine 7-1. The outlet of the cold side pipeline of the first inorganic heat storage device 4-1 is connected to the main steam port of the first turbine 7-1.

[0122] The heat storage tubes 11-3 inside the generator 11 are several horizontally placed circular stainless steel tubes; the heat storage tubes 11-3 are arranged in a staggered pattern in the vertical direction.

[0123] The heat storage tube 11-3 is filled with a first organic heat storage material, which includes sugar alcohols.

[0124] The second heat exchange tube 11-2 is divided into two parts, located at the upper and lower parts of the generator 11. A heat storage tube 11-3 is provided between the two parts of the second heat exchange tube 11-2, located in the middle of the generator 11.

[0125] The gas outlet of the second gas-liquid heat exchanger 3-2 is connected to the inlet of the second heat exchange tube 11-2, and the outlet of the second heat exchange tube 11-2 is also connected to a dust removal and purification device 14.

[0126] The organic heat storage device 13 is equipped with a matching second concave concentrating mirror 15, which focuses sunlight onto the heated surface of the organic heat storage device 13.

[0127] The organic heat storage device 13 is filled with a second organic heat storage material, which includes sugar alcohols.

[0128] The second power generation unit includes a second turbine 7-2 and a second generator 8-2. The second turbine 7-2 is shaft-connected to the second generator 8-2, and the exhaust port of the second turbine 7-2 is connected to the inlet of the second condenser 9-2.

[0129] A circulation pump is installed on the connecting pipe between the second condenser 9-2 and the liquid-liquid heat exchanger.

[0130] The liquid-liquid heat exchanger includes a first liquid-liquid heat exchanger 16-1 and a second liquid-liquid heat exchanger 16-2. The outlet of the second condenser 9-2 is connected to the inlet of the second mixer 10-2 via the cold side pipeline of the first liquid-liquid heat exchanger 16-1, the cold side pipeline of the second liquid-liquid heat exchanger 16-2, and the hot side pipeline of the first liquid-liquid heat exchanger 16-1 in sequence.

[0131] The hot side piping of the second liquid-liquid heat exchanger 16-2 is connected to the cooling return water piping and the cooling supply water piping.

[0132] A circulation pump is provided on the connecting pipe between the second mixer 10-2 and the spray pipe 11-1 in the generator 11.

[0133] The combined electric and cooling power supply unit also includes a third liquid-liquid heat exchanger 16-3. The outlet of the second mixer 10-2 is connected to the spray pipe 11-1 via the cold side pipeline of the third liquid-liquid heat exchanger 16-3. The bottom outlet of the generator 11 is connected to the inlet of the second mixer 10-2 via the hot side pipeline of the third liquid-liquid heat exchanger 16-3.

[0134] Example 2:

[0135] This embodiment provides a solid particle waste heat recovery system coupled with multi-stage heat storage. The structure of the waste heat recovery system is the same as that in Embodiment 1, except that: the gas-solid separator is a sedimentation separator; the fluidized recovery unit does not include the first concave concentrating mirror 6 and the fourth inorganic heat storage device 4-4; and the heat storage tubes 11-3 are arranged in a vertical direction.

[0136] Example 3:

[0137] This embodiment provides a solid particle waste heat recovery system coupled with multi-stage heat storage. The structure of the waste heat recovery system is the same as that in Embodiment 1, except that: the gas-solid separator and the gas-liquid heat exchanger are both provided with a single stage, the inorganic heat storage device is provided with three stages, the gas-solid separator is an inertial separator, and the liquid-liquid heat exchanger is only provided with a single stage liquid-liquid heat exchanger connected to the cooling water pipeline.

[0138] Example 4:

[0139] This embodiment provides a solid particle waste heat recovery method coupled with multi-stage heat storage. The method uses the system in Embodiment 1 and includes the following steps:

[0140] (1) Solid particles and gas are subjected to countercurrent fluidized heat exchange in the fluidized bed body 1. The particle size range of the solid particles is 1-10 mm, and the temperature is 1400℃. The gas is air, which is introduced by blower 5 and absorbs heat to rise to 200℃ when passing through the fourth inorganic heat storage device 4-4. The fourth inorganic heat storage device 4-4 is filled with sodium nitrate and potassium nitrate in a mass ratio of 1:1 to store the collected solar energy in the form of thermal energy. During the ascent of the heated gas, it passes through the first heat exchange tube 1-1. After heat exchange, fine particles are carried away. The heat exchange fluid in the first heat exchange tube 1-1 is an alloy of liquid gallium, indium, and tin. After heat exchange, the fluid is heated to 700°C and flows through the first inorganic heat storage device 4-1, storing the heat in a 1:1 mass ratio sodium carbonate and calcium carbonate composite material. Particles with a diameter greater than 5 mm are discharged from the lower outlet of the fluidized bed body 1 at a discharge temperature of 124°C. Particles with a diameter less than 5 mm leave from the upper outlet of the fluidized bed body 1 with the gas at a temperature of 686°C. The gas undergoes a first gas-solid separation, a first gas-liquid heat exchange, a second gas-solid separation, and a second gas-liquid heat exchange. The gas-solid separation is a cyclone separation. The solid particles separated after the first gas-solid separation have a diameter of 2-5 mm, and the solid particles separated after the second gas-solid separation have a diameter of 1-2 mm. The gas temperature drops to 450°C after the first gas-liquid heat exchange. After heat exchange, the gas temperature drops to 240℃. The heat transfer fluid after the first gas-liquid heat exchange flows through the second inorganic heat storage device 4-2, storing the heat in the aluminum, copper, and silicon alloy material filled in the second inorganic heat storage device 4-2 with a mass ratio of 68.5:26.5:5. The heat transfer fluid after the second gas-liquid heat exchange flows through the third inorganic heat storage device 4-3, storing the heat in the sodium carbonate and sodium hydroxide composite material filled in the third inorganic heat storage device 4-3 with a mass ratio of 17:83.

[0141] (2) The heating return water at a temperature of 70℃ flows sequentially through the cold-side pipelines of the third inorganic thermal storage device 4-3, the second inorganic thermal storage device 4-2, and the first inorganic thermal storage device 4-1 for heating. After flowing through the third inorganic thermal storage device 4-3, the temperature rises to 95℃ and splits into two streams. One stream serves as the heating feed water, and the other enters the cold-side pipeline of the second inorganic thermal storage device 4-2. The feed water flowing through the second inorganic thermal storage device 4-2 changes from liquid to saturated steam at a temperature of 277℃ and splits into two streams again. One stream enters the steam inlet of the first turbine 7-1, and the other enters the first inorganic thermal storage device 4-1. The saturated steam flowing through the cold side pipeline of the heat device 4-1 is transformed into superheated steam, reaching a temperature of 536℃. It then enters the main steam port of the first turbine 7-1. The steam entering the main steam port and the make-up steam port of the first turbine 7-1 drives the first turbine 7-1 to rotate and do work, driving the first generator 8-1 to generate electricity. The temperature of the exhaust steam after doing work drops to 53.5℃, and then condenses at this temperature to form a liquid phase. It mixes with the heating return water and is heated by the steam extracted from the steam port of the first turbine 7-1. The resulting mixed fluid is circulated into each stage of the inorganic heat storage device.

[0142] (3) After gas-liquid heat exchange in step (1), the gas enters the second heat exchange tube 11-2 and heat storage tube 11-3 for heat exchange. The gas temperature drops to 86℃ and is discharged after purification and dust removal. The heat storage tube 11-3 is filled with erythritol. At the same time, atomized concentrated ammonia solution is sprayed through the nozzle of spray pipe 11-1. The concentration of concentrated ammonia solution is 25.5wt% and the temperature is 86℃. It passes through the surface of the second heat exchange tube 11-2 and heat storage tube 11-3 from top to bottom. During the downward movement of the concentrated ammonia solution, some ammonia and water evaporate. The gas-liquid mixture formed enters the gas-liquid separator 12 and is separated into two streams. One stream is ammonia vapor and the other stream is the first dilute ammonia solution. The temperature of the gas-liquid separation is 91.5℃ and the pressure is 0.084MPa. The ammonia vapor is heated and pressurized by the heat stored in the organic heat storage device 13. The temperature reaches 178℃ and the pressure reaches 0.74MPa, forming superheated ammonia vapor for steam power generation. The organic heat storage device 13 contains The mannitol filling stores the collected solar energy as thermal energy. The ammonia vapor enters the second turbine 7-2 to expand and do work, driving the second generator 8-2 to generate electricity. After doing work, the temperature of the exhaust steam drops to -18℃ and the pressure drops to 0.18MPa. The exhaust steam condenses to -24℃ to form a gas-liquid mixture. It first undergoes a liquid-liquid heat exchange, and then exchanges heat with the cooling water. The temperature of the cooling water drops from 12℃ to 7℃, and then undergoes a second liquid-liquid heat exchange. The first liquid-liquid heat exchange and the second liquid-liquid heat exchange are heat exchanges in the same heat exchanger. The gas-liquid mixture serves as the cold source and the heat source, respectively. The gas-liquid mixture after heat exchange is mixed with the first dilute ammonia solution with a concentration of 8.5wt% obtained after gas-liquid separation, and the second dilute ammonia solution with a concentration of 9wt% flowing out from the bottom of generator 11. After mixing, a concentrated ammonia solution is obtained again and enters the spray pipe 11-1. Before entering the spray pipe 11-1, it exchanges heat with the second dilute ammonia solution flowing out from the bottom of generator 11 to raise its temperature.

[0143] Example 5:

[0144] This embodiment provides a solid particle waste heat recovery method coupled with multi-stage heat storage. The method uses the system in Embodiment 1 and includes the following steps:

[0145] (1) Solid particles and gas are subjected to countercurrent fluidized heat exchange in the fluidized bed body 1. The particle size range of the solid particles is 0.5-12 mm, and the temperature is 1200℃. The gas is air, which is introduced by blower 5 and absorbs heat to rise to 240℃ when passing through the fourth inorganic heat storage device 4-4. The fourth inorganic heat storage device 4-4 is filled with sodium nitrate and potassium nitrate in a mass ratio of 2:1 to store the collected solar energy in the form of thermal energy. During the ascent of the heated gas, it passes through the first heat exchange tube 1- After heat exchange, the fluid carries away fine particles. The heat exchange fluid in the first heat exchange tube 1-1 is an alloy of liquid gallium, indium, and tin. After heat exchange, the fluid is heated to 750°C and flows through the first inorganic heat storage device 4-1, where the heat is stored in a potassium carbonate and calcium carbonate composite material with a mass ratio of 1:1. Particles with a diameter of 5 mm or larger in the solid particles are discharged from the lower outlet of the fluidized bed body 1 at a discharge temperature of 130°C. Particles with a diameter range of less than 5 mm leave the upper outlet of the fluidized bed body 1 with the gas. At this time, the gas temperature is 692℃. The gas passes through a first gas-solid separation, a first gas-liquid heat exchange, a second gas-solid separation, and a second gas-liquid heat exchange in sequence. The gas-solid separation is a cyclone separation. The solid particles separated after the first gas-solid separation have a particle size of 2-5 mm. The solid particles separated after the second gas-solid separation have a particle size of 0.5-2 mm. The gas temperature drops to 440℃ after the first gas-liquid heat exchange and to 235℃ after the second gas-liquid heat exchange. The heat transfer fluid after the first gas-liquid heat exchange flows through the second inorganic heat storage device 4-2, where the heat is stored in an aluminum, copper, and silicon alloy material with a mass ratio of 6:3:1 filled in the second inorganic heat storage device 4-2. The heat transfer fluid after the second gas-liquid heat exchange flows through the third inorganic heat storage device 4-3, where the heat is stored in a potassium carbonate and potassium hydroxide composite material with a mass ratio of 1:2 filled in the third inorganic heat storage device 4-3.

[0146] (2) The heating return water at a temperature of 75℃ flows sequentially through the cold-side pipelines of the third inorganic thermal storage device 4-3, the second inorganic thermal storage device 4-2, and the first inorganic thermal storage device 4-1 for heating. After flowing through the third inorganic thermal storage device 4-3, the temperature rises to 98℃ and splits into two streams. One stream serves as the heating feed water, and the other enters the cold-side pipeline of the second inorganic thermal storage device 4-2. The feed water flowing through the second inorganic thermal storage device 4-2 changes from liquid to saturated steam at a temperature of 281℃ and splits into two streams again. One stream enters the steam inlet of the first turbine 7-1, and the other enters the first inorganic thermal storage device 4-1. The saturated steam flowing through the cold side pipeline of the heat device 4-1 is transformed into superheated steam, reaching a temperature of 538°C. It then enters the main steam port of the first turbine 7-1. The steam entering the main steam port and the make-up steam port of the first turbine 7-1 drives the first turbine 7-1 to rotate and do work, which drives the first generator 8-1 to generate electricity. After doing work, the temperature of the exhaust steam drops to 54.5°C, and then condenses at this temperature to form a liquid phase. It mixes with the heating return water and is heated by the steam extracted from the steam port of the first turbine 7-1. The resulting mixed fluid is circulated into each stage of the inorganic heat storage device.

[0147] (3) After gas-liquid heat exchange in step (1), the gas enters the second heat exchange tube 11-2 and exchanges heat with the heat storage tube 11-3. The gas temperature drops to 88℃, and after purification and dust removal, it is discharged into the air. The heat storage tube 11-3 is filled with modified erythritol. At the same time, atomized concentrated ammonia solution is sprayed through the nozzle of the spray pipe 11-1. The concentration of the concentrated ammonia solution is 26.5wt%, and the temperature is 87℃. It passes through the surface of the second heat exchange tube 11-2 and the heat storage tube 11-3 from top to bottom. The concentrated ammonia solution flows downward. During the process, some ammonia and water evaporate, forming a gas-liquid mixture that enters the gas-liquid separator 12. After gas-liquid separation, it is divided into two streams: one is ammonia vapor, and the other is a first dilute ammonia solution. The temperature of the gas-liquid separation is 93.5℃, and the pressure is 0.09MPa. The ammonia vapor is heated and pressurized by the heat stored in the organic heat storage device 13, reaching a temperature of 174℃ and a pressure of 0.78MPa, forming superheated ammonia vapor for steam power generation. The organic heat storage device 13 is filled with... The mannitol collected will store the solar energy as thermal energy. The ammonia vapor will expand and do work in the second turbine 7-2, driving the second generator 8-2 to generate electricity. After doing work, the temperature of the exhaust steam will drop to -20°C and the pressure will drop to 0.23 MPa. The exhaust steam will condense to -25°C to form a gas-liquid mixture. It will first undergo a liquid-liquid heat exchange, and then exchange heat with the cooling water. The temperature of the cooling water will drop from 15°C to 10°C. Then it will undergo a second liquid-liquid heat exchange. The first liquid-liquid heat exchange and the second liquid-liquid heat exchange are heat exchange in the same heat exchanger. The gas-liquid mixture will serve as the cold source and the heat source, respectively. The gas-liquid mixture after heat exchange will be mixed with the first dilute ammonia solution with a concentration of 10.5 wt% obtained after gas-liquid separation, and the second dilute ammonia solution with a concentration of 10 wt% flowing out from the bottom of the generator 11. After mixing, a concentrated ammonia solution will be obtained again and enter the spray pipe 11-1. Before entering the spray pipe 11-1, it will first exchange heat with the second dilute ammonia solution flowing out from the bottom of the generator 11 to raise its temperature.

[0148] Example 6:

[0149] This embodiment provides a solid particle waste heat recovery method coupled with multi-stage heat storage. The method uses the system in Embodiment 1 and includes the following steps:

[0150] (1) Solid particles and gas are subjected to countercurrent fluidized heat exchange in the fluidized bed body 1. The particle size range of the solid particles is 2-15 mm, and the temperature is 1600℃. The gas is air, which is introduced by blower 5 and absorbs heat to rise to 260℃ when passing through the fourth inorganic heat storage device 4-4. The fourth inorganic heat storage device 4-4 is filled with sodium nitrate and potassium nitrate in a mass ratio of 1:2 to store the collected solar energy in the form of thermal energy. During the ascent of the heated gas, it passes through the first heat exchange tube 1- After heat exchange, the fluid carries away fine particles. The heat exchange fluid in the first heat exchange tube 1-1 is an alloy of liquid indium and tin. After heat exchange, the fluid is heated to 850°C and flows through the first inorganic heat storage device 4-1, where the heat is stored in a sodium carbonate and calcium carbonate composite material with a mass ratio of 3:2. Particles with a diameter of 5 mm or larger are discharged from the lower outlet of the fluidized bed body 1 at a discharge temperature of 134°C. Particles smaller than 5 mm leave the fluidized bed body 1 with the gas at the upper outlet. The gas temperature is 698°C. The gas passes through a first gas-solid separation, a first gas-liquid heat exchange, a second gas-solid separation, and a second gas-liquid heat exchange. The gas-solid separation is a cyclone separation. The solid particles separated after the first gas-solid separation have a particle size of 3-5 mm, and the solid particles separated after the second gas-solid separation have a particle size of 2-3 mm. The gas temperature drops to 425°C after the first gas-liquid heat exchange and to 225°C after the second gas-liquid heat exchange. The heat transfer fluid after the first gas-liquid heat exchange flows through the second inorganic heat storage device 4-2, where the heat is stored in an aluminum, copper, and silicon alloy material with a mass ratio of 13:6:1. The heat transfer fluid after the second gas-liquid heat exchange flows through the third inorganic heat storage device 4-3, where the heat is stored in a sodium carbonate and sodium hydroxide composite material with a mass ratio of 1:4.

[0151] (2) The heating return water at a temperature of 65℃ flows sequentially through the cold-side pipelines of the third inorganic thermal storage device 4-3, the second inorganic thermal storage device 4-2, and the first inorganic thermal storage device 4-1 for heating. After flowing through the third inorganic thermal storage device 4-3, the temperature rises to 90℃ and splits into two streams. One stream serves as the heating feed water, and the other enters the cold-side pipeline of the second inorganic thermal storage device 4-2. The feed water flowing through the second inorganic thermal storage device 4-2 changes from liquid to saturated steam at a temperature of 275℃ and splits into two streams again. One stream enters the steam inlet of the first turbine 7-1, and the other enters the first inorganic thermal storage device 4-1. The saturated steam flowing through the cold side pipeline of the thermal storage device 4-1 is transformed into superheated steam at a temperature of 542°C. It then enters the main steam port of the first turbine 7-1. The steam entering the main steam port and the make-up steam port of the first turbine 7-1 drives the first turbine 7-1 to rotate and do work, which in turn drives the first generator 8-1 to generate electricity. The temperature of the exhaust steam after doing work drops to 52°C, and then it condenses at this temperature to form a liquid phase. It mixes with the heating return water and is heated by the steam extracted from the steam extraction port of the first turbine 7-1. The resulting mixed fluid is circulated into each stage of the inorganic thermal storage device.

[0152] (3) After gas-liquid heat exchange in step (1), the gas enters the second heat exchange tube 11-2 and heat storage tube 11-3 for heat exchange. The gas temperature drops to 94℃ and is discharged after purification and dust removal. The heat storage tube 11-3 is filled with erythritol. At the same time, atomized concentrated ammonia solution is sprayed through the nozzle of spray pipe 11-1. The concentration of concentrated ammonia solution is 28.5wt% and the temperature is 89℃. It passes through the surface of the second heat exchange tube 11-2 and heat storage tube 11-3 from top to bottom. During the downward movement of the concentrated ammonia solution, some ammonia and water evaporate. The gas-liquid mixture formed enters the gas-liquid separator 12 and is separated into two streams. One stream is ammonia vapor and the other stream is the first dilute ammonia solution. The temperature of the gas-liquid separation is 90.5℃ and the pressure is 0.092MPa. The ammonia vapor is heated and pressurized by the heat stored in the organic heat storage device 13. The temperature reaches 164℃ and the pressure reaches 0.65MPa, forming superheated ammonia vapor for steam power generation. The organic heat storage device 13 contains The mannitol filling stores the collected solar energy as thermal energy; the ammonia vapor enters the second turbine 7-2 to expand and do work, driving the second generator 8-2 to generate electricity. After doing work, the temperature of the exhaust steam drops to -24℃ and the pressure drops to 0.16MPa. The exhaust steam after doing work condenses to -30℃ to form a gas-liquid mixture. It first undergoes a liquid-liquid heat exchange, and then exchanges heat with the cooling water. The temperature of the cooling water drops from 10℃ to 4℃, and then undergoes a second liquid-liquid heat exchange. The first liquid-liquid heat exchange and the second liquid-liquid heat exchange are heat exchanges in the same heat exchanger. The gas-liquid mixture serves as the cold source and the heat source, respectively. The gas-liquid mixture after heat exchange is mixed with the first dilute ammonia solution with a concentration of 12wt% obtained after gas-liquid separation, and the second dilute ammonia solution with a concentration of 12wt% flowing out from the bottom of the generator 11. After mixing, a concentrated ammonia solution is obtained again and enters the spray pipe 11-1. Before entering the spray pipe 11-1, it first exchanges heat with the second dilute ammonia solution flowing out from the bottom of the generator 11 to raise its temperature.

[0153] As can be seen from the above embodiments, the system of the present invention combines solid particle fluidization technology with multi-stage thermal storage technology through the setting of units such as fluidized bed recovery, combined power generation and combined power generation and cooling. It achieves graded recovery of waste heat from high-temperature solid particles with a wide particle size range according to different particle sizes, and realizes efficient heat storage and deep tiered utilization by setting up multi-stage thermal storage devices matched to the waste heat temperature. The system uses the stored heat for power generation, heating, and cooling, with diverse applications, and solves the problem of stable output of recovered heat. In the present invention, some thermal storage devices utilize solar energy for heat collection, improving the temperature and quality of the corresponding working fluid to enhance the energy conversion efficiency and overall thermal utilization rate of the entire system. The system has a reasonable structural design, stable operation, low cost, and wide application range.

[0154] The applicant declares that the present invention is illustrated through the above embodiments with detailed apparatus and methods, but the present invention is not limited to the above detailed apparatus and methods, that is, it does not mean that the present invention must rely on the above detailed apparatus and methods to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the apparatus of the present invention, additions of auxiliary devices, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A solid particle waste heat recovery system coupled with multi-stage heat storage, characterized in that, The waste heat recovery system includes a fluidized bed recovery unit, a combined heat and power (CHP) unit, and a combined cooling and power (CCHP) unit. The fluidized bed recovery unit includes a fluidized bed body, a gas-solid separator, a gas-liquid heat exchanger, and an inorganic heat storage device. The gas-solid separator and the gas-liquid heat exchanger each have at least one stage, and the gas-solid separator and the gas-liquid heat exchanger are arranged alternately in sequence. The inorganic heat storage device has at least one more stage than the heat exchanger. The top of the fluidized bed body has a solid particle inlet, and the upper outlet of the fluidized bed body is connected to the first-stage gas-solid separator. The fluidized bed body has a first heat exchange tube, and the outlet and inlet of the first heat exchange tube are both connected to the first-stage inorganic heat storage device. The cold source outlet and cold source inlet of the gas-liquid heat exchanger are correspondingly connected to the inorganic heat storage devices after the first stage. The combined heat and power unit includes a first power generation unit, a first condenser, and a first mixer. The inlet of the first mixer is connected to a heating return water pipeline, and the outlet of the first mixer is sequentially connected to the inlet of a multi-stage inorganic heat storage device. The outlet of the inorganic heat storage device is connected to a heating water supply pipeline and the first power generation unit. The gas outlet of the first power generation unit is sequentially connected to the first condenser and the first mixer. The combined electric and cooling power supply unit includes a generator, a gas-liquid separator, an organic thermal storage device, a second power generation unit, a second condenser, a liquid-liquid heat exchanger, and a second mixer. The generator is equipped with a spray pipe, a second heat exchange pipe, and a thermal storage pipe. The spray pipe is located at the top inside the generator. The second heat exchange pipe and the thermal storage pipe are arranged alternately. The top outlet of the generator is connected to the inlet of the gas-liquid separator, and the bottom outlet of the generator is connected to the inlet of the second mixer. The liquid phase outlet of the gas-liquid separator is connected to the second mixer. The gas phase outlet of the gas-liquid separator is connected to the second power generation unit via the organic thermal storage device. The gas outlet of the second power generation unit is connected to the second mixer in sequence via the second condenser and the liquid-liquid heat exchanger. The heat source pipeline of the liquid-liquid heat exchanger is connected to the cooling return water pipeline and the cooling supply water pipeline, respectively. The outlet of the second mixer is connected to the spray pipe in the generator.

2. The waste heat recovery system according to claim 1, characterized in that, The fluidized bed body has an air inlet at the bottom and a coarse particle outlet at the bottom.

3. The waste heat recovery system according to claim 1, characterized in that, Both the gas-solid separator and the gas-liquid heat exchanger are provided in two stages, namely a first gas-solid separator, a first gas-liquid heat exchanger, a second gas-solid separator, and a second gas-liquid heat exchanger connected in sequence. The lower part of the first gas-solid separator and the second gas-solid separator are provided with fine particle outlets.

4. The waste heat recovery system according to claim 1, characterized in that, The gas-solid separator includes any one or a combination of at least two of the following: a cyclone separator, an inertial separator, or a settling separator.

5. The waste heat recovery system according to claim 1, characterized in that, In the inorganic heat storage device, the first inorganic heat storage device is connected to the first heat exchange tube, the second inorganic heat storage device is connected to the cold source outlet and cold source inlet of the first gas-liquid heat exchanger, and the third inorganic heat storage device is connected to the cold source outlet and cold source inlet of the second gas-liquid heat exchanger.

6. The waste heat recovery system according to claim 5, characterized in that, A circulating pump is provided on the connecting pipelines between the first heat exchange tube and the first inorganic heat storage device, the first gas-liquid heat exchanger and the second inorganic heat storage device, and the second gas-liquid heat exchanger and the third inorganic heat storage device.

7. The waste heat recovery system according to claim 5, characterized in that, The first inorganic thermal storage device is filled with an inorganic carbonate composite material.

8. The waste heat recovery system according to claim 5, characterized in that, The second inorganic thermal storage device is filled with an alloy composite material.

9. The waste heat recovery system according to claim 5, characterized in that, The third inorganic thermal storage device is filled with a composite material of alkali metal salts and alkali metal hydroxides.

10. The waste heat recovery system according to claim 1, characterized in that, The fluidized bed recovery unit also includes a blower, the outlet of which is connected to the air inlet of the fluidized bed body.

11. The waste heat recovery system according to claim 1, characterized in that, The fluidized bed recovery unit also includes a first concave concentrating mirror and a fourth inorganic heat storage device. One end of the heat exchange pipe of the fourth inorganic heat storage device is connected to the outlet of the blower, and the other end is connected to the air inlet of the fluidized bed body. The first concave concentrating mirror focuses sunlight onto the heated surface of the fourth inorganic heat storage device.

12. The waste heat recovery system according to claim 11, characterized in that, The fourth inorganic thermal storage device is filled with inorganic nitrate composite material.

13. The waste heat recovery system according to claim 1, characterized in that, The first power generation unit includes a first turbine and a first generator. The first turbine is connected to the shaft of the first generator, and the exhaust port of the first turbine is connected to the inlet of the first condenser.

14. The waste heat recovery system according to claim 13, characterized in that, The first turbine is provided with a steam extraction port, which is connected to the inlet of the first mixer.

15. The waste heat recovery system according to claim 1, characterized in that, A circulation pump is independently provided on the connecting pipes of the first condenser and the first mixer, as well as on the connecting pipes of the first mixer and the inorganic heat storage device.

16. The waste heat recovery system according to claim 1, characterized in that, The outlet of the first mixer is sequentially connected to the third inorganic thermal storage device, the second inorganic thermal storage device, and the first inorganic thermal storage device.

17. The waste heat recovery system according to claim 1, characterized in that, The outlet of the first mixer is first connected to the inlet of the cold-side pipeline of the third inorganic thermal storage device. The outlet of the cold-side pipeline of the third inorganic thermal storage device is divided into two branches: one branch is connected to the heating water supply pipeline, and the other branch is connected to the inlet of the cold-side pipeline of the second inorganic thermal storage device. The outlet of the cold-side pipeline of the second inorganic thermal storage device is divided into two branches: one branch is connected to the inlet of the cold-side pipeline of the first inorganic thermal storage device, and the other branch is connected to the steam injection port of the first turbine. The outlet of the cold-side pipeline of the first inorganic thermal storage device is connected to the main steam port of the first turbine.

18. The waste heat recovery system according to claim 1, characterized in that, The heat storage tubes inside the generator are several horizontally placed circular metal tubes.

19. The waste heat recovery system according to claim 18, characterized in that, The heat storage tube inside the generator is a circular stainless steel tube.

20. The waste heat recovery system according to claim 1, characterized in that, The heat storage tubes are arranged in a staggered and / or parallel configuration in the vertical direction.

21. The waste heat recovery system according to claim 1, characterized in that, The heat storage tube is filled with a first organic heat storage material, which includes sugar alcohols.

22. The waste heat recovery system according to claim 21, characterized in that, The first organic thermal storage material includes erythritol.

23. The waste heat recovery system according to claim 1, characterized in that, The second heat exchange tube is divided into two parts, located at the upper and lower parts of the generator, and a heat storage tube is provided between the two parts of the second heat exchange tube, located in the middle of the generator.

24. The waste heat recovery system according to claim 1, characterized in that, The gas outlet of the second gas-liquid heat exchanger is connected to the inlet of the second heat exchange tube, and the outlet of the second heat exchange tube is also connected to a dust removal and purification device.

25. The waste heat recovery system according to claim 1, characterized in that, The organic thermal storage device is equipped with a matching second concave concentrator, which focuses sunlight onto the heated surface of the organic thermal storage device.

26. The waste heat recovery system according to claim 1, characterized in that, The organic thermal storage device is filled with a second organic thermal storage material, which includes sugar alcohols.

27. The waste heat recovery system according to claim 26, characterized in that, The second organic thermal storage material includes mannitol.

28. The waste heat recovery system according to claim 1, characterized in that, The second power generation unit includes a second turbine and a second generator. The second turbine is connected to the shaft of the second generator, and the exhaust port of the second turbine is connected to the inlet of the second condenser.

29. The waste heat recovery system according to claim 1, characterized in that, A circulation pump is installed on the connecting pipe between the second condenser and the liquid-liquid heat exchanger.

30. The waste heat recovery system according to claim 1, characterized in that, The liquid-liquid heat exchanger includes a first liquid-liquid heat exchanger and a second liquid-liquid heat exchanger. The outlet of the second condenser is connected to the inlet of the second mixer via the cold side pipeline of the first liquid-liquid heat exchanger, the cold side pipeline of the second liquid-liquid heat exchanger, and the hot side pipeline of the first liquid-liquid heat exchanger in sequence.

31. The waste heat recovery system according to claim 30, characterized in that, The hot-side piping of the second liquid-liquid heat exchanger is connected to the cooling return water piping and the cooling supply water piping.

32. The waste heat recovery system according to claim 1, characterized in that, A circulation pump is installed on the connecting pipe between the second mixer and the spray pipe in the generator.

33. The waste heat recovery system according to claim 1, characterized in that, The combined electric and cooling power supply unit also includes a third liquid-liquid heat exchanger. The outlet of the second mixer is connected to the spray pipe via the cold side pipe of the third liquid-liquid heat exchanger, and the bottom outlet of the generator is connected to the inlet of the second mixer via the hot side pipe of the third liquid-liquid heat exchanger.

34. A method for recovering waste heat from solid particles using the system described in any one of claims 1-33, characterized in that, The method includes the following steps: (1) Solid particles and gas are subjected to countercurrent fluidized heat exchange in the fluidized bed body. After the gas is heated, it exchanges heat with the first heat exchange tube and carries the fine particles away. It passes through at least one gas-solid separation and gas-liquid heat exchange in sequence. After the coarse particles settle, they are discharged from the bottom of the fluidized bed body. The heat carried by the fluid after heat exchange through the first heat exchange tube and gas-liquid heat exchange is stored in a multi-stage inorganic heat storage device. (2) After the heating return water is heated by the cold side pipeline of the inorganic heat storage device described in step (1), it is divided into two streams. One stream provides heating water, and the other stream forms steam for steam power generation. The exhaust steam after power generation is condensed and mixed with the heating return water. (3) Step (1) The gas after gas-liquid heat exchange enters the second heat exchange tube and the heat storage tube for heat exchange. At the same time, concentrated ammonia water solution is sprayed out through the spray pipe from top to bottom through the surface of the second heat exchange tube and the heat storage tube. After some ammonia water evaporates, it is separated into two streams by gas-liquid separation. One stream is ammonia vapor and the other stream is dilute ammonia water solution. The ammonia vapor is heated by the organic heat storage device and then used for steam power generation. The exhaust steam after power generation is condensed, liquid-liquid heat exchanged and mixed with the dilute ammonia water solution obtained after gas-liquid separation and the part of concentrated ammonia water solution that has not evaporated after heat exchange. After mixing, concentrated ammonia water solution is obtained again and enters the spray pipe.

35. The method according to claim 34, characterized in that, The particle size range of the solid particles in step (1) is 0.1~15mm, and the temperature is 1200~1600℃.

36. The method according to claim 34, characterized in that, The gas in step (1) includes preheated air, which is introduced by a blower and heated to 180~280°C when passing through the fourth inorganic heat storage device.

37. The method according to claim 36, characterized in that, The fourth inorganic thermal storage device is filled with inorganic nitrate composite material.

38. The method according to claim 36, characterized in that, The fourth inorganic thermal storage device is filled with alkali metal nitrates.

39. The method according to claim 36, characterized in that, The fourth inorganic thermal energy storage device stores the collected solar energy in the form of thermal energy, and its internal temperature is maintained at 200~300℃.

40. The method according to claim 34, characterized in that, In step (1), the gas rises through the first heat exchange tube, heating the heat exchange fluid in the first heat exchange tube to 650~850°C. The heat exchange fluid in the first heat exchange tube includes any one or at least two of liquid metal gallium, indium, or tin.

41. The method according to claim 34, characterized in that, The heat exchange fluid in the first heat exchange tube flows through the first inorganic heat storage device, storing heat in the first inorganic heat storage device, and its internal temperature is maintained at 600~800℃.

42. The method according to claim 41, characterized in that, The first inorganic thermal storage device is filled with an inorganic carbonate composite material.

43. The method according to claim 42, characterized in that, The first inorganic thermal storage device is filled with alkali metal carbonates and / or alkaline earth metal carbonates.

44. The method according to claim 34, characterized in that, The solid particles with a diameter range of 5-15 mm are discharged from the lower outlet of the fluidized bed body, and the discharge temperature is 120-140℃.

45. The method according to claim 34, characterized in that, The solid particles with a diameter range of 0.1 to 5 mm leave the fluidized bed body from the upper outlet along with the gas, at which time the gas temperature is 680 to 700°C.

46. ​​The method according to claim 34, characterized in that, The gas-solid separation and gas-liquid heat exchange in step (1) are performed twice, and the operation sequence is as follows: first gas-solid separation, first gas-liquid heat exchange, second gas-solid separation and second gas-liquid heat exchange.

47. The method according to claim 34, characterized in that, The gas-solid separation includes any one or a combination of at least two of cyclone separation, inertial separation, or sedimentation separation.

48. The method according to claim 46, characterized in that, The solid particles separated after the first gas-solid separation have a particle size of 2-5 mm, and the solid particles separated after the second gas-solid separation have a particle size of 0.1-2 mm.

49. The method according to claim 46, characterized in that, The gas temperature drops to 420~460℃ after the first gas-liquid heat exchange, and the gas temperature drops to 220~250℃ after the second gas-liquid heat exchange.

50. The method according to claim 46, characterized in that, The heat exchange fluids for the primary and secondary gas-liquid heat exchanges independently include heat transfer oil.

51. The method according to claim 46, characterized in that, The heat exchange fluid after the first gas-liquid heat exchange flows through the second inorganic heat storage device, where the heat is stored and the internal temperature is maintained at 300~600℃.

52. The method according to claim 51, characterized in that, The second inorganic thermal storage device is filled with an alloy composite material.

53. The method according to claim 52, characterized in that, The filling material inside the second inorganic thermal storage device is a combination of at least two of aluminum, copper, or silicon.

54. The method according to claim 46, characterized in that, The heat exchange fluid after the secondary gas-liquid heat exchange flows through the third inorganic heat storage device, where the heat is stored and the internal temperature is maintained at 200~300℃.

55. The method according to claim 54, characterized in that, The third inorganic thermal storage device is filled with a composite material of alkali metal salts and alkali metal hydroxides.

56. The method according to claim 34, characterized in that, The temperature of the heating return water in step (2) is 65~75℃.

57. The method according to claim 34, characterized in that, In step (2), the heating return water flows sequentially through the cold side pipelines of the third inorganic heat storage device, the second inorganic heat storage device, and the first inorganic heat storage device for heating.

58. The method according to claim 34, characterized in that, The temperature of the return water for heating rises to 90-98°C after flowing through the cold side pipeline of the third inorganic thermal storage device. It then splits into two streams: one stream serves as the heating supply water, and the other stream enters the cold side pipeline of the second inorganic thermal storage device.

59. The method according to claim 58, characterized in that, The feedwater flowing through the cold-side pipeline of the second inorganic thermal storage device changes from liquid to saturated steam at a temperature of 273~283℃, and then splits into two streams. One stream enters the steam inlet of the first turbine, and the other stream enters the cold-side pipeline of the first inorganic thermal storage device.

60. The method according to claim 59, characterized in that, The saturated steam flowing through the cold-side pipeline of the first inorganic thermal storage device is transformed into superheated steam, reaching a temperature of 535~545℃, and then enters the main steam port of the first turbine.

61. The method according to claim 60, characterized in that, Steam entering the main steam inlet and the make-up steam inlet of the first turbine drives the first turbine to rotate and do work, which in turn drives the first generator to generate electricity. The temperature of the exhaust steam after doing work drops to 52~56℃.

62. The method according to claim 61, characterized in that, After performing work, the exhaust steam condenses to 52~56℃ to form a liquid phase, mixes with the heating return water, and is heated by the steam extracted from the steam extraction port of the first turbine. The resulting mixed fluid is then circulated into the inorganic heat storage device.

63. The method according to claim 34, characterized in that, The gas after gas-liquid heat exchange in step (3) is cooled to 85-95°C after passing through the second heat exchange tube, and then discharged after purification and dust removal.

64. The method according to claim 34, characterized in that, In step (3), the heat storage tube is filled with a first organic heat storage material, which includes sugar alcohols.

65. The method according to claim 64, characterized in that, The first organic thermal storage material includes erythritol.

66. The method according to claim 64, characterized in that, The temperature of the first organic thermal storage material in the thermal storage tube is maintained at 110~150℃.

67. The method according to claim 34, characterized in that, In step (3), the concentrated ammonia solution is sprayed into the spray pipe after being atomized by the nozzle. The concentration of the concentrated ammonia solution is 25~30wt%, and the temperature is 85~90℃.

68. The method according to claim 34, characterized in that, As the concentrated ammonia solution moves downwards, some ammonia and water evaporate, and the resulting gas-liquid mixture enters the gas-liquid separator.

69. The method according to claim 34, characterized in that, The temperature for gas-liquid separation in step (3) is 90~95℃ and the pressure is 0.08~0.1MPa.

70. The method according to claim 34, characterized in that, In step (3), the ammonia vapor is heated and pressurized by the heat stored in the organic heat storage device, reaching a temperature of 160~180℃ and a pressure of 0.6~0.8MPa, thus forming superheated ammonia vapor.

71. The method according to claim 34, characterized in that, The organic thermal storage device is filled with a second organic thermal storage material, which includes sugar alcohols.

72. The method according to claim 71, characterized in that, The second organic thermal storage material includes mannitol.

73. The method according to claim 34, characterized in that, The organic thermal storage device stores the collected solar energy as thermal energy, and its internal temperature is maintained at 150~200℃.

74. The method according to claim 34, characterized in that, The dilute ammonia solution obtained from the gas-liquid separation in step (3) is the first dilute ammonia solution with a concentration of 8.5~12.5wt%.

75. The method according to claim 34, characterized in that, The portion of the concentrated ammonia solution that did not evaporate after heat exchange in step (3) is the second dilute ammonia solution, which flows out from the bottom of the generator and has a concentration of 8.5~12.5wt%.

76. The method according to claim 34, characterized in that, In step (3), the ammonia vapor enters the second turbine to expand and do work, driving the second generator to generate electricity. After doing work, the temperature of the exhaust steam drops to -25~-15℃ and the pressure drops to 0.15~0.24MPa.

77. The method according to claim 76, characterized in that, After performing work, the exhaust steam condenses to -30~-20℃ to form a gas-liquid mixture, which exchanges heat with the cooling water, reducing the temperature of the cooling water from 10~15℃ to 4~10℃.

78. The method according to claim 77, characterized in that, The condensed gas-liquid mixture first undergoes a liquid-liquid heat exchange, then exchanges heat with the cooling water, and then undergoes a second liquid-liquid heat exchange. The first and second liquid-liquid heat exchanges are heat exchanges in the same heat exchanger, with the gas-liquid mixture serving as the cold source and heat source, respectively.

79. The method according to claim 34, characterized in that, Step (3) After the multiple fluids are mixed, they are heated by heat exchange before entering the spray pipe. The fluid that exchanges heat with it is the second dilute ammonia solution flowing out from the bottom of the generator.

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