Integrated system and method for power generation and seawater desalination based on dry quenching waste heat utilization

Abstract

The application relates to a power generation and seawater desalination integrated system and method based on dry quenching waste heat utilization. The inert gas outlet of the dry quenching furnace in the power generation and seawater desalination integrated system is communicated with a CO2 waste heat boiler. The inert gas outlet of the CO2 waste heat boiler is communicated with a first seawater desalination device. The inert gas outlet of the first seawater desalination device is communicated with the dry quenching furnace. The CO2 gas outlet of the CO2 waste heat boiler is communicated with a power generation device. The CO2 gas outlet of the power generation device is communicated with a CO2 circulation module, the CO2 gas outlet of the CO2 circulation module is communicated with a second seawater desalination device, the CO2 gas outlet of the second seawater desalination device is communicated with the CO2 circulation module, and the CO2 gas outlet of the CO2 circulation module is communicated with the CO2 waste heat boiler. The beneficial effects are that carbon is reduced, water is not consumed, and water is produced. The waste heat utilization rate is improved, power generation and fresh water preparation are increased, costs are reduced, heat exchange efficiency and power generation efficiency are improved, the occupied space is reduced, the process flow is shortened, and the equipment cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of dry quenching waste heat utilization technology, and in particular to an integrated system and method for power generation and seawater desalination based on dry quenching waste heat utilization. Background Technology

[0002] Dry quenching is a process in which inert gas is used to cool red-hot coke during the coking process. The cooled coke is discharged from the bottom of the furnace, and the high-temperature inert gas, after absorbing heat, is introduced into a waste heat boiler where it is cooled by water. The high-temperature, high-pressure steam generated by the water absorbing heat and evaporating is used to drive a steam turbine to generate electricity. This power generation technology is a commonly used dry quenching waste heat utilization technology and belongs to the traditional Rankine cycle steam turbine power generation technology.

[0003] However, the following problems exist in this dry quenching waste heat utilization technology:

[0004] High water consumption. Cooling high-temperature inert gases using water consumes a significant amount of water. Industries using dry quenching technology (such as steel) are high water-consuming industries, generally facing water shortages, which are a widespread problem.

[0005] The heat utilization rate is low. The residual heat of the cooled inert gas and the high-temperature, high-pressure water vapor after heat absorption is not fully utilized.

[0006] Both heat exchange efficiency and power generation efficiency are low. The Rankine cycle technology, which uses water to exchange heat with high-temperature inert gases and generates electricity using the resulting steam, is inefficient and cannot meet the current energy transition needs.

[0007] The equipment occupies a large space. Due to the large unit volume of water vapor, the generator sets of traditional steam power generation systems are large in size, and they also require deoxygenated water supply pump stations to remove oxygen from the water to prevent oxidation and corrosion of the equipment, resulting in a large overall size of the equipment.

[0008] Carbon emissions are substantial. The coking process generates a large amount of carbon-containing gases, resulting in high carbon emissions. Developing carbon reduction technologies to achieve process-wide carbon reduction is now urgent, and the promotion and innovation of low-carbon technologies must be strengthened. Summary of the Invention

[0009] (a) Technical problems to be solved

[0010] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides an integrated system and method for power generation and seawater desalination based on the utilization of waste heat from dry quenching coke, which solves the technical problems of high water consumption, low heat utilization rate, low heat exchange efficiency and power generation efficiency, large equipment footprint and high carbon emissions in the current dry quenching coke waste heat utilization technology.

[0011] (II) Technical Solution

[0012] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0013] In a first aspect, embodiments of the present invention provide an integrated power generation and seawater desalination system based on the utilization of waste heat from dry quenching, including a dry quenching furnace, a CO2 waste heat boiler, a power generation device, a first seawater desalination device, a second seawater desalination device, and a CO2 circulation module.

[0014] The inert gas outlet of the dry quenching furnace is connected to a CO2 waste heat boiler, which contains S-CO2 for heat exchange.

[0015] The inert gas outlet of the CO2 waste heat boiler is connected to the first seawater desalination unit; the inert gas outlet of the first seawater desalination unit is connected to the dry quenching furnace.

[0016] The CO2 gas outlet of the CO2 waste heat boiler is connected to the power generation unit; the CO2 gas outlet of the power generation unit is connected to the CO2 circulation module; the CO2 gas outlet of the CO2 circulation module is connected to the second seawater desalination unit; the CO2 gas outlet of the second seawater desalination unit is connected to the CO2 circulation module; and the CO2 gas outlet of the CO2 circulation module is connected to the CO2 waste heat boiler.

[0017] The S-CO2 discharged from the power generation unit is heated by the CO2 circulation module and then enters the second seawater desalination unit; the S-CO2 discharged from the second seawater desalination unit is heated and pressurized by the CO2 circulation module and then enters the CO2 waste heat boiler again.

[0018] According to the present invention, the CO2 cycle module includes a regenerator and a compressor;

[0019] The CO2 gas outlet of the power generation unit is connected to the regenerator, and the S-CO2 discharged from the power generation unit enters the regenerator to release heat; the CO2 gas outlet of the regenerator is connected to the second seawater desalination unit, and the S-CO2 after releasing heat enters the second seawater desalination unit to release heat to desalinate seawater.

[0020] The CO2 gas outlet of the second seawater desalination unit is connected to the compressor, the CO2 gas outlet of the compressor is connected to the regenerator, and the CO2 gas outlet of the regenerator is connected to the CO2 waste heat boiler. After releasing heat, the S-CO2 enters the compressor for pressurization and the regenerator for heating in sequence, and then enters the CO2 waste heat boiler again to absorb heat.

[0021] According to the present invention, the inert gas outlet of the dry quenching furnace is connected to the CO2 waste heat boiler through a first inert gas pipeline, the inert gas outlet of the CO2 waste heat boiler is connected to the first seawater desalination device through a second inert gas pipeline, and the inert gas outlet of the first seawater desalination device is connected to the dry quenching furnace through an inert gas circuit.

[0022] The CO2 gas outlet of the CO2 waste heat boiler is connected to the power generation unit through a first CO2 gas pipeline; the CO2 gas outlet of the power generation unit is connected to the regenerator through a second CO2 gas pipeline; the CO2 gas outlet of the regenerator is connected to the second seawater desalination unit through a third CO2 gas pipeline; the CO2 gas outlet of the second seawater desalination unit is connected to the compressor through a first CO2 gas circuit; the compressor is connected to the regenerator through a second CO2 gas circuit; and the regenerator is connected to the CO2 waste heat boiler through a third CO2 gas circuit.

[0023] According to the present invention, a first dust collector is installed on the first inert gas pipeline, and the inert gas discharged from the dry quenching furnace enters the CO2 waste heat boiler after being dedusted by the first dust collector.

[0024] A second dust collector and a circulating fan are sequentially installed along the flow direction of the inert gas on the second inert gas pipeline. The inert gas discharged from the CO2 waste heat boiler is purged by the second dust collector and then sent into the first seawater desalination unit by the circulating fan.

[0025] According to the present invention, the power generation device includes an S-CO2 turbine and a generator connected to the S-CO2 turbine, wherein the CO2 gas outlet of the CO2 waste heat boiler is connected to the S-CO2 turbine.

[0026] After absorbing heat, the S-CO2 enters the turbine to drive the S-CO2 turbine to rotate, thereby driving the generator to generate electricity.

[0027] According to the present invention, both the first seawater desalination device and the second seawater desalination device are distilled seawater desalination devices.

[0028] The freshwater outlets of both the first and second seawater desalination units are connected to the freshwater discharge device; the concentrated brine outlets of both the first and second seawater desalination units are connected to the concentrated brine discharge device.

[0029] According to the present invention, the inert gas is N2.

[0030] According to the present invention, a finned coil heat exchanger is provided in the CO2 waste heat boiler.

[0031] Secondly, the present invention also provides a power generation and seawater desalination method based on an integrated power generation and seawater desalination system utilizing waste heat from dry quenching, comprising the following steps:

[0032] S1: The inert gas in the dry quenching furnace absorbs heat to cool the red-hot coke and then enters the CO2 waste heat boiler to exchange heat with S-CO2;

[0033] S2: The inert gas after exothermic reaction enters the first seawater desalination unit to desalinate the seawater. The inert gas discharged from the first seawater desalination unit re-enters the dry quenching furnace to absorb heat and cool the red-hot coke.

[0034] After absorbing heat, the S-CO2 enters the power generation unit to drive power generation. The S-CO2 discharged from the power generation unit releases heat through the CO2 circulation module and then enters the second seawater desalination unit to release heat and desalinate seawater. The S-CO2 discharged from the second seawater desalination unit absorbs heat and is pressurized through the CO2 circulation module and then enters the CO2 waste heat boiler to absorb heat again.

[0035] According to the present invention, the temperature of the inert gas discharged from the dry quenching furnace is 900-980°C;

[0036] The temperature of the S-CO2 entering the CO2 waste heat boiler is 500℃ and the pressure is 31MPa;

[0037] The temperature of the S-CO2 discharged from the CO2 waste heat boiler is 600℃ and the pressure is 30MPa;

[0038] The temperature of the inert gas discharged from the CO2 waste heat boiler is 160-170℃;

[0039] The temperature of the inert gas discharged from the first seawater desalination unit is 130℃.

[0040] (III) Beneficial Effects

[0041] The beneficial effects of this invention are as follows: The integrated power generation and seawater desalination system and method based on the utilization of waste heat from dry quenching coke, by setting up an integrated power generation and seawater desalination system and method based on the utilization of waste heat from dry quenching coke, using supercritical carbon dioxide (S-CO2) in a gas-liquid two-phase state at a temperature exceeding 31.3℃ and a pressure of 7.38MPa as the circulating heat exchange medium, and in conjunction with the overall setup of the integrated power generation and seawater desalination system, has the following advantages:

[0042] This system reduces carbon emissions, consumes no water, produces water, and increases efficiency. By installing a CO2 waste heat boiler, using supercritical carbon dioxide (S-CO2) at a temperature exceeding 31.3℃ and a pressure of 7.38 MPa, in a gas-liquid two-phase state, as the heat exchange medium, it extracts heat from the inert gases after absorbing the heat from red-hot coke. This heat can synergize with carbon capture and utilization technology (CCUS) to extract carbon-containing gases generated during coking and other production processes, forming S-CO2. The waste heat from the S-CO2 heat exchange is then used for seawater desalination and power generation, achieving carbon reduction, efficiency improvement, and environmental friendliness. Simultaneously, by replacing water with S-CO2 for circulating heat exchange, no water resources are consumed, and the waste heat can be used to produce fresh water through the first and second seawater desalination units, achieving increased water production efficiency.

[0043] This method improves waste heat utilization, enables the recycling of heat exchange media, and enhances efficiency in power generation and freshwater production using the heat exchange media, while reducing the costs of power generation and seawater desalination. After extracting heat from inert gases using S-CO2, the heat from the absorbed S-CO2 is sequentially used to generate electricity and desalinate seawater through a second desalination unit according to temperature and pressure gradients. Meanwhile, the waste heat from the released heat of the inert gases is used to desalinate seawater through a first desalination unit. This diversifies the heat sources for seawater desalination, enabling the utilization of S-CO2 and inert gas waste heat through aeration, increasing the waste heat utilization rate to over 90%, and providing multiple heat sources for seawater distillation and desalination. Compared to traditional dry quenching waste heat utilization technology, which can only use steam for power generation, this application utilizes the waste heat from S-CO2 and inert gases to produce freshwater and uses S-CO2 under high temperature and pressure for power generation. This results in more diversified products, significantly improving efficiency, and providing more diverse heat sources for seawater desalination, fully utilizing waste heat. Furthermore, the inert gas after seawater desalination can be recycled to cool the red-hot coke again, and the S-CO2 after power generation and seawater desalination can be recycled to exchange heat with the inert gas again, realizing the recycling of inert gas and S-CO2, improving the utilization rate of heat exchange medium, reducing the amount of inert gas and S-CO2 used again, and utilizing the low-grade waste heat of red-hot coke in dry quenching for power generation and seawater desalination, thus reducing costs.

[0044] The heat exchange efficiency is improved. As a heat exchange medium with a temperature exceeding 31.3℃ and a pressure of 7.38MPa that exists between gas and liquid phases, S-CO2 has better fluidity and diffusivity than water. By setting up a CO2 waste heat boiler and using S-CO2 as the heat exchange medium, the heat of the inert gas after absorbing the heat of the red-hot coke can be extracted. This fully utilizes the characteristics of S-CO2, such as its large specific heat capacity and strong radiative heat exchange capacity, thus improving the heat exchange efficiency for the inert gas.

[0045] The power generation efficiency is improved. Power generation is achieved by extracting heat from inert gas and then generating S-CO2 under high temperature and pressure, employing the Reyton cycle power generation technology. Compared to steam Rankine cycle power generation technology, the S-CO2 in the Reyton cycle is in a supercritical state between the gas and liquid phases, avoiding changes in the working fluid phase, reducing compression work consumption, and significantly improving cycle efficiency, thereby increasing power generation efficiency and economic benefits. Therefore, the power generation efficiency of this application is 3-5% higher than that of traditional steam Rankine cycle power generation technology.

[0046] This reduces the equipment's footprint, shortens the process flow, and lowers equipment costs. Because the unit volume of S-CO2 is smaller than that of steam, the volume of the power generation unit in this application is only 1 / 25th that of a steam turbine unit. Simultaneously, by using S-CO2 as the power generation medium to replace water for heat exchange, the feedwater system of the steam waste heat boiler is eliminated, shortening the process flow, reducing equipment costs and water production costs, and reducing equipment size. It also eliminates the need to consider equipment oxidation and corrosion issues, and removes the deaeration water supply pump station required by traditional dry quenching waste heat power generation systems. This achieves a reduction in overall equipment size and a shortened feedwater process, thereby lowering equipment costs. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the integrated power generation and seawater desalination system based on the utilization of waste heat from dry quenching, according to the present invention.

[0048] [Explanation of Labels in the Attached Image]

[0049] A: CO2 and inert gas heat exchange subsystem; B: Seawater desalination subsystem;

[0050] 1: Dry quenching furnace;

[0051] 2: CO2 waste heat boiler;

[0052] 3: Power generation unit; 31: S-CO2 turbine; 32: Generator;

[0053] 41: First seawater desalination unit; 42: Second seawater desalination unit;

[0054] 5: CO2 circulation module; 51: Regenerator; 52: Compressor;

[0055] 61: First dust collector; 62: Second dust collector; 63: Circulating fan;

[0056] 71: Freshwater discharge device; 72: Concentrated brine discharge device; 73: Freshwater discharge pipeline; 74: Concentrated brine discharge pipeline;

[0057] 81: First inert gas pipeline; 82: Second inert gas pipeline; 83: Inert gas circuit;

[0058] 91: First CO2 gas pipeline; 92: Second CO2 gas pipeline; 93: Third CO2 gas pipeline; 94: First CO2 gas circuit; 95: Second CO2 gas circuit; 96: Third CO2 gas circuit. Detailed Implementation

[0059] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] See Figure 1 The integrated power generation and seawater desalination system based on the utilization of waste heat from dry quenching proposed in this embodiment of the invention includes a dry quenching furnace 1, a CO2 waste heat boiler 2, a power generation device 3, a first seawater desalination device 41, a second seawater desalination device 42, and a CO2 circulation module 5. Wherein, S-CO2 is supercritical carbon dioxide in a state between gas and liquid phases exceeding 31.3℃ and 7.38MPa.

[0061] The inert gas in the dry quenching furnace 1 is used to absorb the heat from the red-hot coke. The inert gas outlet of the dry quenching furnace 1 is connected to the CO2 waste heat boiler 2, which contains S-CO2 for heat exchange. The S-CO2 and the inert gas in the CO2 waste heat boiler 2 exchange heat.

[0062] The inert gas outlet of the CO2 waste heat boiler 2 is connected to the first seawater desalination unit 41. The inert gas outlet of the first seawater desalination unit 41 is connected to the dry quenching furnace 1.

[0063] The CO2 gas outlet of the CO2 waste heat boiler 2 is connected to the power generation unit 3. The CO2 gas outlet of the power generation unit 3 is connected to the CO2 circulation module 5. The CO2 gas outlet of the CO2 circulation module 5 is connected to the second seawater desalination unit 42. The CO2 gas outlet of the second seawater desalination unit 42 is connected to the CO2 circulation module 5. The CO2 gas outlet of the CO2 circulation module 5 is connected to the CO2 waste heat boiler 2. The S-CO2 discharged from the power generation unit 3 enters the second seawater desalination unit 42 after being heated by the CO2 circulation module 5. The S-CO2 discharged from the second seawater desalination unit 42 re-enters the CO2 waste heat boiler 2 after being heated and pressurized by the CO2 circulation module 5.

[0064] Specifically, the power generation and seawater desalination method based on the integrated power generation and seawater desalination system utilizing waste heat from dry quenching includes the following steps:

[0065] S1: The inert gas in the dry quenching furnace 1 absorbs heat to cool the red-hot coke and then enters the CO2 waste heat boiler 2 to exchange heat with S-CO2.

[0066] S2: The inert gas after exothermic reaction enters the first seawater desalination unit 41 to release heat and desalinate the seawater. The inert gas discharged from the first seawater desalination unit 41 re-enters the dry quenching furnace 1 to absorb heat and cool the red-hot coke.

[0067] After absorbing heat, the S-CO2 enters the power generation unit 3 to drive power generation. The S-CO2 discharged from the power generation unit 3 releases heat through the CO2 circulation module 5 and then enters the second seawater desalination unit 42 to release heat and desalinate seawater. The S-CO2 discharged from the second seawater desalination unit 42 absorbs heat and is pressurized through the CO2 circulation module 5 before entering the CO2 waste heat boiler 2 for heat absorption.

[0068] By setting up an integrated power generation and seawater desalination system and method based on the utilization of waste heat from dry quenching, using supercritical carbon dioxide (S-CO2) at a temperature exceeding 31.3℃ and a pressure of 7.38 MPa in a gas-liquid two-phase state as the circulating heat exchange medium, and in conjunction with the overall setup of the integrated power generation and seawater desalination system, the following advantages are achieved:

[0069] This system reduces carbon emissions, consumes no water, produces water, and increases efficiency. By installing a CO2 waste heat boiler, using supercritical carbon dioxide (S-CO2) at a temperature exceeding 31.3℃ and a pressure of 7.38 MPa, in a gas-liquid two-phase state, as the heat exchange medium, it extracts heat from the inert gases after absorbing the heat from red-hot coke. This heat can synergize with carbon capture and utilization technology (CCUS) to extract carbon-containing gases generated during coking and other production processes, forming S-CO2. The waste heat from the S-CO2 heat exchange is then used for seawater desalination and power generation, achieving carbon reduction, efficiency improvement, and environmental friendliness. Simultaneously, by replacing water with S-CO2 for circulating heat exchange, no water resources are consumed, and the waste heat can be used to produce fresh water through the first and second seawater desalination units, achieving increased water production efficiency.

[0070] This technology improves waste heat utilization, enables the recycling of heat exchange media, and enhances efficiency by utilizing the heat exchange media for power generation and freshwater production. It also reduces the costs of power generation and seawater desalination, and diversifies the products, allowing for simultaneous power generation and seawater desalination using waste heat. After extracting heat from inert gases using S-CO2, the heat from the absorbed S-CO2 is sequentially used to generate electricity through a power generation device and to desalinate seawater through a second seawater desalination device, following temperature and pressure gradients. Meanwhile, the waste heat from the released heat of the inert gases is used to desalinate seawater through a first seawater desalination device. This achieves the aeration utilization of S-CO2 and inert gas waste heat, increasing the waste heat utilization rate to over 90%, and providing multiple heat sources for seawater distillation and desalination. Compared to traditional dry quenching waste heat utilization technology, which can only use steam for power generation, this application utilizes the waste heat release of S-CO2 and inert gases to produce freshwater and uses S-CO2 under high temperature and pressure for power generation. This results in more diversified products, significantly improving efficiency, and providing more diverse heat sources for seawater desalination, fully utilizing waste heat. Furthermore, the inert gas after seawater desalination can be recycled to cool the red-hot coke again, and the S-CO2 after power generation and seawater desalination can be recycled to exchange heat with the inert gas again, realizing the recycling of inert gas and S-CO2, improving the utilization rate of heat exchange medium, reducing the amount of inert gas and S-CO2 used again, and utilizing the low-grade waste heat of red-hot coke in dry quenching for power generation and seawater desalination, thus reducing costs.

[0071] The heat exchange efficiency is improved. As a heat exchange medium with a temperature exceeding 31.3℃ and a pressure of 7.38MPa that exists between gas and liquid phases, S-CO2 has better fluidity and diffusivity than water. By setting up a CO2 waste heat boiler and using S-CO2 as the heat exchange medium, the heat of the inert gas after absorbing the heat of the red-hot coke can be extracted. This fully utilizes the characteristics of S-CO2, such as its large specific heat capacity and strong radiative heat exchange capacity, thus improving the heat exchange efficiency for the inert gas.

[0072] The power generation efficiency is improved. Power generation is achieved by extracting heat from inert gas and then generating S-CO2 under high temperature and pressure, employing the Reyton cycle power generation technology. Compared to steam Rankine cycle power generation technology, the S-CO2 in the Reyton cycle is in a supercritical state between the gas and liquid phases, avoiding changes in the working fluid phase, reducing compression work consumption, and significantly improving cycle efficiency, thereby increasing power generation efficiency and economic benefits. Therefore, the power generation efficiency of this application is 3-5% higher than that of traditional steam Rankine cycle power generation technology.

[0073] This reduces the equipment's footprint, shortens the process flow, and lowers equipment costs. Because the unit volume of S-CO2 is smaller than that of steam, the volume of the power generation unit in this application is only 1 / 25th that of a steam turbine unit. Simultaneously, by using S-CO2 as the power generation medium to replace water for heat exchange, the feedwater system of the steam waste heat boiler is eliminated, shortening the process flow, reducing equipment costs and water production costs, and reducing equipment size. It also eliminates the need to consider equipment oxidation and corrosion issues, and removes the deaeration water supply pump station required by traditional dry quenching waste heat power generation systems. This achieves a reduction in overall equipment size and a shortened feedwater process, thereby lowering equipment costs.

[0074] Furthermore, the temperature of the inert gas discharged from the dry quenching furnace 1 is 900-980℃.

[0075] The temperature of the S-CO2 entering the CO2 waste heat boiler 2 is 500℃ and the pressure is 31MPa.

[0076] The temperature of the S-CO2 discharged from CO2 waste heat boiler 2 is 600℃ and the pressure is 30MPa.

[0077] The temperature of the inert gas discharged from CO2 waste heat boiler 2 is 160-170℃.

[0078] The temperature of the inert gas discharged from the first seawater desalination unit 41 is 130°C.

[0079] Preferably, the CO2 waste heat boiler 2 is equipped with finned coil heat exchange tubes, and S-CO2 is contained in the finned coil heat exchange tubes to improve the heat exchange efficiency between S-CO2 and inert gas.

[0080] Preferably, the inert gas is N2.

[0081] Specifically, the inert gas outlet of the dry quenching furnace 1 is connected to the CO2 waste heat boiler 2 through the first inert gas pipeline 81.

[0082] The inert gas outlet of the CO2 waste heat boiler 2 is connected to the first seawater desalination unit 41 through the second inert gas pipeline 82, and the inert gas outlet of the first seawater desalination unit 41 is connected to the dry quenching furnace 1 through the inert gas circuit 83.

[0083] The CO2 gas outlet of the CO2 waste heat boiler 2 is connected to the power generation unit 3 through the first CO2 gas pipeline 91.

[0084] The CO2 gas outlet of the power generation unit 3 is connected to the CO2 circulation module 5 via the second CO2 gas pipeline 92. The CO2 gas outlet of the CO2 circulation module 5 is connected to the second seawater desalination unit 42 via the third CO2 gas pipeline 93.

[0085] The CO2 gas outlet of the second seawater desalination unit 42 is connected to the CO2 circulation module 5 through the first CO2 gas circuit 94. The CO2 gas outlet of the CO2 circulation module 5 is connected to the CO2 waste heat boiler 2 through the third CO2 gas circuit 96.

[0086] Furthermore, a first dust collector 6 is installed on the first inert gas pipeline 81. The inert gas discharged from the dry quenching furnace 1 enters the CO2 waste heat boiler 2 after being dedusted by the first dust collector 6.

[0087] A second dust collector 62 and a circulating fan 63 are sequentially installed along the flow direction of the inert gas on the second inert gas pipeline 82. The inert gas discharged from the CO2 waste heat boiler 2 is filtered by the second dust collector 62 and then sent into the first seawater desalination device 41 by the circulating fan 63.

[0088] Furthermore, the power generation unit 3 includes an S-CO2 turbine 31 and a generator 32 connected to the S-CO2 turbine 31, and the CO2 gas outlet of the CO2 waste heat boiler 2 is connected to the S-CO2 turbine 31.

[0089] After absorbing heat, the S-CO2 enters the turbine 31 to drive the S-CO2 turbine 31 to rotate, thereby driving the generator 32 to generate electricity.

[0090] Furthermore, the CO2 cycle module 5 includes a regenerator 51 and a compressor 52.

[0091] The CO2 gas outlet of the power generation unit 3 is connected to the regenerator 51, and the S-CO2 discharged from the power generation unit 3 enters the regenerator 51 to release heat. The CO2 gas outlet of the regenerator 51 is connected to the second seawater desalination unit 42, and the released S-CO2 enters the second seawater desalination unit 42 to release heat and desalinate seawater. The CO2 gas outlet of the second seawater desalination unit 42 is connected to the compressor 52, the CO2 gas outlet of the compressor 52 is connected to the regenerator 51, and the CO2 gas outlet of the regenerator 51 is connected to the CO2 waste heat boiler 2. After releasing heat, the S-CO2 sequentially enters the compressor 52 for pressurization and the regenerator 51 for heating, and then re-enters the CO2 waste heat boiler 2 to absorb heat.

[0092] Specifically, the CO2 gas outlet of the power generation unit 3 is connected to the regenerator 51 via the second CO2 gas pipeline 92. The CO2 gas outlet of the regenerator 51 is connected to the second seawater desalination unit 42 via the third CO2 gas pipeline 93. The CO2 gas outlet of the second seawater desalination unit 42 is connected to the compressor 52 via the first CO2 gas circuit 94. The compressor 52 is connected to the regenerator 51 via the second CO2 gas circuit 95. The regenerator 51 is connected to the CO2 waste heat boiler 2 via the third CO2 gas circuit 96.

[0093] Furthermore, both the first seawater desalination unit 41 and the second seawater desalination unit 42 are distillation seawater desalination units. The inert gas in the first seawater desalination unit 41 releases heat, causing the seawater to absorb heat and evaporate to form water vapor, which then condenses to form fresh water.

[0094] Specifically, the freshwater outlets of both the first seawater desalination unit 41 and the second seawater desalination unit 42 are connected to the freshwater discharge device 71 via the freshwater discharge pipe 73 to discharge freshwater. The concentrated brine outlets of both the first seawater desalination unit 41 and the second seawater desalination unit 42 are connected to the concentrated brine discharge device 72 via the concentrated brine discharge pipe 74 to discharge concentrated brine.

[0095] Concentrated brine is seawater with a high salt content after distillation.

[0096] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0097] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An integrated power generation and seawater desalination system based on the utilization of waste heat from dry quenching, characterized in that, It includes a dry quenching furnace (1), a CO2 waste heat boiler (2), a power generation unit (3), a first seawater desalination unit (41), a second seawater desalination unit (42), and a CO2 circulation module (5); The inert gas outlet of the dry quenching furnace (1) is connected to the CO2 waste heat boiler (2), which contains S-CO2 for heat exchange. The inert gas outlet of the CO2 waste heat boiler (2) is connected to the first seawater desalination device (41); the inert gas outlet of the first seawater desalination device (41) is connected to the dry quenching furnace (1); The CO2 gas outlet of the CO2 waste heat boiler (2) is connected to the power generation device (3); the CO2 gas outlet of the power generation device (3) is connected to the CO2 circulation module (5); the CO2 gas outlet of the CO2 circulation module (5) is connected to the second seawater desalination device (42); the CO2 gas outlet of the second seawater desalination device (42) is connected to the CO2 circulation module (5); and the CO2 gas outlet of the CO2 circulation module (5) is connected to the CO2 waste heat boiler (2). The S-CO2 discharged from the power generation device (3) enters the second seawater desalination device (42) after being heated by the CO2 circulation module (5); the S-CO2 discharged from the second seawater desalination device (42) enters the CO2 waste heat boiler (2) again after being heated and pressurized by the CO2 circulation module (5).

2. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 1, characterized in that, The CO2 circulation module (5) includes a regenerator (51) and a compressor (52); The CO2 gas outlet of the power generation device (3) is connected to the regenerator (51), and the S-CO2 discharged by the power generation device (3) enters the regenerator (51) to release heat; the CO2 gas outlet of the regenerator (51) is connected to the second seawater desalination device (42), and the S-CO2 after releasing heat enters the second seawater desalination device (42) to release heat to desalinate seawater; The CO2 gas outlet of the second seawater desalination device (42) is connected to the compressor (52), the CO2 gas outlet of the compressor (52) is connected to the regenerator (51), and the CO2 gas outlet of the regenerator (51) is connected to the CO2 waste heat boiler (2). After releasing heat, the S-CO2 enters the compressor (52) for pressurization and the regenerator (51) for heating in sequence, and then enters the CO2 waste heat boiler (2) again to absorb heat.

3. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 2, characterized in that, The inert gas outlet of the dry quenching furnace (1) is connected to the CO2 waste heat boiler (2) through the first inert gas pipeline (81), the inert gas outlet of the CO2 waste heat boiler (2) is connected to the first seawater desalination device (41) through the second inert gas pipeline (82), and the inert gas outlet of the first seawater desalination device (41) is connected to the dry quenching furnace (1) through the inert gas circuit (83). The CO2 gas outlet of the CO2 waste heat boiler (2) is connected to the power generation device (3) through the first CO2 gas pipeline (91); the CO2 gas outlet of the power generation device (3) is connected to the regenerator (51) through the second CO2 gas pipeline (92); the CO2 gas outlet of the regenerator (51) is connected to the second seawater desalination device (42) through the third CO2 gas pipeline (93); the CO2 gas outlet of the second seawater desalination device (42) is connected to the compressor (52) through the first CO2 gas circuit (94); the compressor (52) is connected to the regenerator (51) through the second CO2 gas circuit (95); and the regenerator (51) is connected to the CO2 waste heat boiler (2) through the third CO2 gas circuit (96).

4. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 3, characterized in that, A first dust collector (6) is installed on the first inert gas pipeline (81). The inert gas discharged from the dry quenching furnace (1) enters the CO2 waste heat boiler (2) after being dedusted by the first dust collector (6). A second dust collector (62) and a circulating fan (63) are sequentially arranged along the flow direction of the inert gas on the second inert gas pipeline (82). The inert gas discharged from the CO2 waste heat boiler (2) is purged by the second dust collector (62) and then sent into the first seawater desalination device (41) by the circulating fan (63).

5. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 1, characterized in that, The power generation device (3) includes an S-CO2 turbine (31) and a generator (32) connected to the S-CO2 turbine (31). The CO2 gas outlet of the CO2 waste heat boiler (2) is connected to the S-CO2 turbine (31). After absorbing heat, the S-CO2 enters the S-CO2 turbine (31) to drive the S-CO2 turbine (31) to rotate, thereby driving the generator (32) to generate electricity.

6. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 1, characterized in that, Both the first seawater desalination device (41) and the second seawater desalination device (42) are distilled seawater desalination devices; The freshwater outlets of the first seawater desalination device (41) and the second seawater desalination device (42) are both connected to the freshwater discharge device (71); the brine outlets of the first seawater desalination device (41) and the second seawater desalination device (42) are both connected to the brine discharge device (72).

7. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 1, characterized in that, The inert gas is N2.

8. The integrated power generation and seawater desalination system based on waste heat utilization in dry quenching as described in claim 1, characterized in that, The CO2 waste heat boiler (2) is equipped with finned coil heat exchange tubes.

9. A method for power generation and seawater desalination based on an integrated power generation and seawater desalination system utilizing waste heat from dry quenching as described in claim 1, characterized in that, Includes the following steps: S1: The inert gas in the dry quenching furnace (1) absorbs heat and cools the red-hot coke before entering the CO2 waste heat boiler (2) to exchange heat with the S-CO2; S2: The inert gas after exothermic reaction enters the first seawater desalination device (41) to deheat and desalinate the seawater. The inert gas discharged from the first seawater desalination device (41) re-enters the dry quenching furnace (1) to absorb heat and cool the red-hot coke. After absorbing heat, the S-CO2 enters the power generation device (3) to drive power generation. The S-CO2 discharged from the power generation device (3) releases heat through the CO2 circulation module (5) and then enters the second seawater desalination device (42) to release heat and desalinate seawater. The S-CO2 discharged from the second seawater desalination device (42) absorbs heat and is pressurized by the CO2 circulation module (5) and then enters the CO2 waste heat boiler (2) again to absorb heat.

10. The power generation and seawater desalination method based on the integrated power generation and seawater desalination system utilizing waste heat from dry quenching as described in claim 9, characterized in that, The temperature of the inert gas discharged from the dry quenching furnace (1) is 900-980℃; The temperature of the S-CO2 entering the CO2 waste heat boiler (2) is 500°C and the pressure is 31 MPa; The temperature of the S-CO2 discharged from the CO2 waste heat boiler (2) is 600℃ and the pressure is 30MPa; The temperature of the inert gas discharged from the CO2 waste heat boiler (2) is 160-170℃; The temperature of the inert gas discharged from the first seawater desalination device (41) is 130°C.

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