Carbon-based fuel quality-divided conversion system and method based on photovoltaic photo-thermal coupling

Abstract

The invention provides a carbon-based fuel quality-divided conversion system and method based on photovoltaic photo-thermal coupling, and the system comprises a photo-thermal heat storage system which is used for converting light energy into heat energy; the photovoltaic heat storage system is used for converting light energy into electric energy and heat energy; the raw material thermal cracking module is used for receiving the heat energy output by the photo-thermal heat storage system, so that the carbon-based fuel is subjected to a pyrolytic reaction, and gaseous volatile components and solid semicoke are formed; the volatile component upgrading pyrolysis module is used for receiving heat energy output by the photovoltaic heat storage system so as to carry out deep cracking reaction on gaseous volatile components to obtain synthesis gas; and the solid coke quality-divided utilization module is used for receiving the electric energy output by the photovoltaic heat storage system so as to carry out solid coke quality-divided utilization on the solid semi-coke to obtain at least one of high-purity semi-coke, a low-boiling-point substance and a high-boiling-point substance. According to the system provided by the invention, by combining the advantages of photovoltaic and photo-thermal technologies, electric energy and heat energy are provided for other modules for realizing quality-divided conversion of the carbon-based fuel, and the energy utilization efficiency is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of energy and environmental protection technology, and in particular to a carbon-based fuel mass conversion system and method based on photovoltaic and thermal coupling. Background Art

[0002] Carbon-based fuels, especially coal, biomass and waste plastics, have long occupied an important position in the global energy supply. However, traditional carbon-based fuel processing technologies face many challenges, especially in terms of energy efficiency, environmental protection and resource utilization efficiency. Although current processes such as pyrolysis, gasification and combustion can effectively extract energy and chemical products, they generally have problems such as high energy consumption and large carbon dioxide emissions. These processes often rely on high-temperature reactions, with huge energy consumption and low conversion efficiency, and are also accompanied by a large amount of greenhouse gas emissions, which greatly restricts the goals of sustainable development and low-carbon economy. For example, when coal gasification technology operates at high temperature, it consumes about 3.5 tons of coal to produce 1 ton of synthesis gas, and will produce corresponding carbon dioxide emissions, which seriously affects the realization of environmental protection goals. Similarly, the pyrolysis process of waste plastics also has high energy consumption, and harmful gases may be released during the production process, further aggravating environmental pollution.

[0003] In addition, existing technologies are still relatively single in terms of energy supply, often relying on fossil energy or electric drive, and lack solutions for multi-source coupling and coordinated efficient utilization. For example, traditional waste conversion facilities often rely on electric heating or natural gas heating, resulting in low overall system efficiency and insufficient energy utilization. Therefore, how to reduce energy consumption, improve energy conversion efficiency, and effectively reduce carbon dioxide emissions have become core issues that need to be urgently addressed in current carbon-based fuel conversion technologies.

[0004] In view of the fact that existing carbon-based fuel conversion methods usually have problems such as high energy consumption and high carbon emissions, the technology of applying solar energy technology to carbon-based fuel processing has been proposed. However, in traditional technologies, the application of solar energy in carbon-based fuel utilization is mostly concentrated on single photothermal or photovoltaic conversion. The independent operation of photothermal / photovoltaic systems leads to low solar energy utilization efficiency and cannot effectively absorb excess solar energy resources. Summary of the invention

[0005] In view of the above problems, one of the purposes of the present invention is to provide a carbon-based fuel mass conversion system based on photovoltaic and thermal coupling, which combines the advantages of photovoltaic and thermal technologies to provide electrical energy and thermal energy for other modules that realize carbon-based fuel mass conversion, reduce carbon dioxide emissions, and realize efficient storage and utilization of solar energy. The second purpose of the present invention is to provide a carbon-based fuel mass conversion method based on photovoltaic and thermal coupling.

[0006] To achieve one of the objectives, in a first aspect, the present invention provides a carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling, and the technical solution adopted is as follows: A carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling, the system comprising: A photovoltaic-thermal energy storage system for receiving sunlight and performing photovoltaic-thermal conversion to obtain thermal energy; A photovoltaic energy storage system for receiving sunlight and performing photovoltaic conversion to obtain electric energy, and performing electro-thermal conversion on the electric energy to obtain thermal energy; A fractional conversion system, including a raw material pyrolysis module, a volatile matter upgrading pyrolysis module, and a solid coke fractional utilization module, the raw material pyrolysis module being used for receiving carbon-based fuel; wherein, The raw material pyrolysis module is connected to the photovoltaic-thermal energy storage system and is used for receiving the thermal energy output by the photovoltaic-thermal energy storage system to cause the carbon-based fuel to undergo a pyrolysis reaction to form gaseous volatile matter and solid semicoke; The volatile matter upgrading pyrolysis module is respectively communicated with the raw material pyrolysis module and the photovoltaic energy storage system, and is used for receiving the thermal energy output by the photovoltaic energy storage system to perform a deep pyrolysis reaction on the gaseous volatile matter to obtain syngas; The solid coke fractional utilization module is communicated with the raw material pyrolysis module and is connected to the photovoltaic energy storage system, and is used for receiving the electric energy output by the photovoltaic energy storage system to perform solid coke fractional utilization on the solid semicoke to obtain at least one of high-purity semicoke, low-boiling point substances, and high-boiling point substances.

[0007] As one of the preferred solutions, the photovoltaic-thermal energy storage system includes a photovoltaic-thermal device, a first high-temperature energy storage tank, a first low-temperature energy storage tank, and solid particles; wherein, the first high-temperature energy storage tank is respectively communicated with the photovoltaic-thermal device and the raw material pyrolysis module; the first low-temperature energy storage tank is respectively communicated with the photovoltaic-thermal device and the raw material pyrolysis module; and the solid particles circulate between the photovoltaic-thermal device, the first high-temperature energy storage tank, the raw material pyrolysis module, and the first low-temperature energy storage tank.

[0008] As one of the preferred solutions, the photovoltaic-thermal energy storage system includes a photovoltaic-thermal device, a first high-temperature energy storage tank, a first low-temperature energy storage tank, solid particles, and a heat exchange gas; wherein, the first high-temperature energy storage tank is respectively communicated with the photovoltaic-thermal device and the raw material pyrolysis module; the first low-temperature energy storage tank is respectively communicated with the photovoltaic-thermal device and the first high-temperature energy storage tank; the solid particles circulate between the photovoltaic-thermal device, the first high-temperature energy storage tank, and the first low-temperature energy storage tank, and the heat exchange gas flows from the first high-temperature energy storage tank to the raw material pyrolysis module.

[0009] As one of the preferred solutions, the solid particles include any one of quartz sand, ceramics, and alumina.

[0010] As one of the preferred solutions, the photovoltaic heat storage system includes: A photovoltaic device for converting the light energy output by the sunlight into electric energy; An electric heating device with heat carrier particles flowing inside and connected to the photovoltaic device, for receiving the electric energy to heat the heat carrier particles; A second high-temperature heat storage tank communicated with the electric heating device, for receiving and storing the heated heat carrier particles; the second high-temperature heat storage tank is communicated with the volatile matter upgrading and pyrolysis module, for transferring the heat of the heat carrier particles to the gaseous volatile matter; A second low-temperature heat storage tank communicated with the volatile matter upgrading and pyrolysis module and the electric heating device respectively, for receiving and storing the heat carrier particles after heat transfer, and sending the heat carrier particles back to the electric heating device.

[0011] As one of the preferred solutions, the raw material pyrolysis module is a pyrolysis reactor; wherein, the pyrolysis reactor includes any one or a combination of a fluidized bed, a downcomer bed, a moving bed and a fixed bed.

[0012] As one of the preferred solutions, the volatile matter upgrading and pyrolysis module is a high-temperature fluidized bed, and the high-temperature fluidized bed is communicated with the raw material pyrolysis module, the second high-temperature heat storage tank and the second low-temperature heat storage tank respectively; Or, the volatile matter upgrading and pyrolysis module includes a tar separation device and a high-temperature fluidized bed, the tar separation device is communicated with the raw material pyrolysis module, and the high-temperature fluidized bed is communicated with the tar separation device, the second high-temperature heat storage tank and the second low-temperature heat storage tank respectively.

[0013] As one of the preferred solutions, the solid coke fraction utilization module includes: A first purification furnace communicated with the raw material pyrolysis module, for receiving and purifying the solid semicoke to form ash-containing semicoke and low-boiling-point gaseous recyclables; A second purification furnace communicated with the first purification furnace, for receiving and purifying the ash-containing semicoke to form high-boiling-point gaseous recyclables and obtaining high-purity semicoke; Wherein, both the first purification furnace and the second purification furnace are connected to the photovoltaic device to be powered and heated by the photovoltaic device; the solid coke fraction utilization module further includes: A first condensation recovery device communicated with the first purification furnace, for receiving and condensing the low-boiling-point gaseous recyclables to obtain low-boiling-point substances; A second condensation recovery device communicated with the second purification furnace, for receiving and condensing the high-boiling-point gaseous recyclables to obtain high-boiling-point substances.

[0014] As one of the preferred solutions, the carbon-based fuel includes any one or combination of coal, biomass, waste plastics, and liquid hydrocarbons.

[0015] To achieve the second objective, in the second aspect, the present invention provides a method for the fractional conversion of carbon-based fuel based on photovoltaic-thermal coupling. The technical solution adopted is as follows: A method for the fractional conversion of carbon-based fuel based on photovoltaic-thermal coupling depends on the fractional conversion system for carbon-based fuel based on photovoltaic-thermal coupling provided in the first aspect of the present invention for fractional conversion. The method includes: S1. Use a solar thermal energy storage system to receive sunlight and perform solar-thermal conversion to obtain thermal energy; S2. Use a photovoltaic energy storage system to receive sunlight and perform photovoltaic conversion to obtain electric energy, and perform electro-thermal conversion on the electric energy to obtain thermal energy; S3. Use a raw material pyrolysis module to receive the thermal energy and carbon-based fuel output by the solar thermal energy storage system, and cause the carbon-based fuel to undergo a pyrolysis reaction to form gaseous volatiles and solid semicoke; S4. Input the gaseous volatiles into a volatile upgrading pyrolysis module, and use the thermal energy generated by the photovoltaic energy storage system to perform a deep pyrolysis reaction on the gaseous volatiles to obtain syngas; S5. Input the solid semicoke into a solid coke fractional utilization module, and use the electric energy generated by the photovoltaic energy storage system to perform solid coke fractional utilization on the solid semicoke to obtain at least one of high-purity semicoke, low-boiling point substances, and high-boiling point substances.

[0016] As one of the preferred solutions, step S1 includes: S11. Transport the solid particles in the first low-temperature energy storage tank to the solar thermal device; S12. Use the solar thermal device to focus sunlight on the solid particles therein and heat the solid particles; S13. Transport the heated solid particles to the first high-temperature energy storage tank for storage; Step S3 includes: S31. Transport the solid particles and carbon-based fuel in the first high-temperature energy storage tank to the raw material pyrolysis module, and transfer the heat of the solid particles to the carbon-based fuel, causing the carbon-based fuel to undergo a pyrolysis reaction; S32. Transport the heat-transferred solid particles to the first low-temperature energy storage tank in step S11 for storage.

[0017] As one of the preferred solutions, step S1 includes: S101. Transport the solid particles in the first low-temperature energy storage tank to the solar thermal device; S102. Use the solar thermal device to focus sunlight on the solid particles therein and heat the solid particles; S103. Transfer the heated solid particles into the first high-temperature heat storage tank, and conduct heat exchange between the solid particles and the heat exchange gas; S104. Return the heat-exchanged solid particles to the first low-temperature heat storage tank; Step S3 includes: S301. Transfer the heat-exchanged heat exchange gas and carbon-based fuel into the raw material pyrolysis module, transfer the heat of the heat exchange gas to the carbon-based fuel, and cause the carbon-based fuel to undergo a pyrolysis reaction.

[0018] As one of the preferred solutions, step S2 includes: S21. Convert sunlight into electric energy by using a photovoltaic device, and directly supply power to the solid coke medium utilization module and the electric heating device; S22. Transfer the heat carrier particles in the second low-temperature heat storage tank into the electric heating device; S23. Heat the heat carrier particles therein by using the electric heating device; S24. Transfer the heated heat carrier particles into the second high-temperature heat storage tank for storage, and complete the electro-thermal conversion; Step S4 includes: S41. Transfer the heat carrier particles in the second high-temperature heat storage tank into the high-temperature fluidized bed, and at the same time, after separating tar from the gaseous volatile matter through a tar separation device or directly input the gaseous volatile matter into the high-temperature fluidized bed, transfer the heat of the heat carrier particles to the gaseous volatile matter, and cause the gaseous volatile matter to undergo a deep pyrolysis reaction; S42. Transfer the heat carrier particles after heat transfer into the second low-temperature heat storage tank in step S22 for storage.

[0019] As one of the preferred solutions, step S5 includes: S51. Input the solid semicoke into the first purification furnace, and use the electric energy provided by the photovoltaic device to fluidize and purify the solid semicoke in an inert atmosphere to form a low-boiling-point gaseous recovery product and ash-containing semicoke; S52. Transfer the low-boiling-point gaseous recovery product into the first condensation recovery device, and obtain the low-boiling-point substance through condensation recovery; S53. Transfer the ash-containing semicoke into the second purification furnace, and use the electric energy provided by the photovoltaic device to purify it in an inert atmosphere to form a high-boiling-point gaseous recovery product, and obtain the high-purity semicoke; S54. Transfer the high-boiling-point gaseous recovery product into the second condensation recovery device, and obtain the high-boiling-point substance after condensation recovery.

[0020] As one of the preferred solutions, when performing the pyrolysis reaction in step S3, a pyrolysis aid is introduced into the raw material pyrolysis module; the pyrolysis aid is any one or a combination of water vapor, oxygen, hydrogen, and methane.

[0021] Compared with the prior art, the present application has the following advantages: 1. The system provided in the embodiment of the present application, through the ingenious coupling of the solar thermal energy storage system and the photovoltaic energy storage system, uses solar energy to provide the heat required for the reaction for other modules (raw material pyrolysis module, volatile matter upgrading pyrolysis module, and solid coke fractional utilization module) for the fractional conversion of carbon-based fuels. Through the synergistic effect of photovoltaic and solar thermal energy, the energy utilization efficiency is effectively improved, the high-efficiency conversion of carbon-based fuels is realized, while greatly reducing the dependence on traditional fossil fuels, reducing carbon dioxide emissions, and achieving low-carbon emissions; 2. The system provided in the embodiment of the present application, through the synergistic effect of the solar thermal energy storage system and the photovoltaic energy storage system, realizes the efficient storage and utilization of solar energy, effectively absorbs the excess solar energy resources, improves the sustainability of energy, and effectively improves the pyrolysis efficiency of carbon-based fuels; 3. The system provided in the embodiment of the present application, by establishing different reaction conditions through the raw material pyrolysis module, the volatile matter upgrading pyrolysis module, and the solid coke fractional utilization module respectively, realizes the fractional conversion of carbon-based fuels, and can obtain various high-value products such as syngas, low-boiling substances, and high-purity semi-coke. The diversification of products provides a variety of raw material choices for different industrial applications and has high economic value.

[0022] All in all, the present invention innovatively uses the combination of solar thermal energy storage and photovoltaic energy storage for the fractional conversion of carbon-based fuels, reduces traditional energy consumption, reduces carbon dioxide emissions, and conforms to the trend of global energy transformation and environmental protection. The condensation recovery and purification processes in the system also help to reduce the emissions of harmful substances, improve the overall environmental protection performance, have prominent environmental benefits, significant economic benefits, and broad application prospects.

[0023] The advantages of the method compared with the prior art are the same as those of the above system and will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the present application, the drawings required for the description of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 is a schematic flow chart of a carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling provided by an embodiment of the present application; Figure 2 It is a flowchart of the steps of a method for the separate conversion of carbon-based fuels based on the coupling of photovoltaic and solar thermal energy provided by an embodiment of the present application. Detailed implementation manners

[0026] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0027] In the related art, in the field of energy technology, solar energy technology has developed rapidly in recent years. Photovoltaic technology can convert sunlight into electrical energy, while solar thermal technology can effectively utilize solar energy to generate high-temperature heat energy. However, the timeliness and instability of solar energy still restrict its wide application. For example, the newly installed photovoltaic capacity globally reached approximately 250 GW in 2023. However, due to changes in sunlight hours and weather conditions, how to efficiently absorb the excess photovoltaic electrical energy remains a major challenge for many countries in the process of energy transformation. According to a report by the International Energy Agency (IEA), despite the substantial increase in solar installed capacity, the power grids in many regions still lack sufficient flexibility to cope with the unstable supply of solar energy, resulting in the frequent occurrence of the phenomenon of "abandoning light". In particular, when there is an excess of solar energy, how to efficiently store it and use it in energy-intensive industrial processes has become an urgent problem to be solved. For example, Germany experienced the phenomenon of "abandoning light" in 2021, and the photovoltaic power in some regions could not be absorbed in time, resulting in energy waste and grid fluctuations. Therefore, how to deeply integrate solar energy with industrial production processes to achieve flexible absorption and efficient utilization has become a key issue in current energy technology.

[0028] Although existing research has attempted to apply the abundant solar energy to the treatment of carbon-based fuels, most technologies still focus on the conversion or independent application of a single energy source, with low energy conversion and utilization efficiency, and no effective industrial application solutions have been formed, such as the coupling of photovoltaic and solar thermal energy. In the process of carbon-based fuel conversion, how to use solar energy to provide the required high-temperature heat energy and electrical energy to efficiently drive processes such as pyrolysis and gasification to achieve the separate conversion of carbon-based fuels remains a technical problem that has not been fully solved. Existing research mostly focuses on the separate application of photovoltaic or solar thermal technologies, lacking innovation in energy supply, heat energy management, and multi-source coupling, and unable to fully utilize the potential of solar energy.

[0029] Therefore, there is an urgent need for a new type of carbon-based fuel conversion technology that can combine the advantages of photovoltaic and solar thermal technologies, utilize solar energy to provide efficient energy support for the carbon-based fuel conversion process, and at the same time, through multi-stage reactions and heat energy recovery, maximize the energy utilization efficiency, reduce the dependence on fossil energy, and reduce carbon emissions. Inventing a carbon-based fuel separate conversion technology that combines photovoltaic and solar thermal coupling can not only improve the energy efficiency of the conversion process, reduce the high energy consumption problem of traditional methods, but also provide a new solution for the consumption of solar energy and promote the wide application of clean energy.

[0030] In view of this, the present invention introduces a photovoltaic-thermal coupling technology in the carbon-based fuel conversion, which uses solar energy to provide both high-efficiency heat energy and electrical energy. This technology can not only improve the energy utilization efficiency, reduce the dependence on fossil energy, and lower carbon dioxide emissions, but also effectively solve the problem of solar energy consumption and promote the optimization of the low-carbon economy and energy structure. Specifically, referring to Figure 1 as shown Figure 1 is a schematic flow chart of a carbon-based fuel separate conversion system based on photovoltaic-thermal coupling provided by the present invention. In the first aspect, the present invention provides a carbon-based fuel separate conversion system based on photovoltaic-thermal coupling. The system includes: a solar thermal energy storage system for receiving sunlight and performing solar-thermal conversion to obtain heat energy; a photovoltaic energy storage system for receiving sunlight and performing photovoltaic conversion to obtain electrical energy, and performing electro-thermal conversion on the electrical energy to obtain heat energy; a separate conversion system including a raw material pyrolysis module, a volatile matter upgrading pyrolysis module, and a solid coke separate utilization module. The raw material pyrolysis module is used to receive the carbon-based fuel. Among them, the raw material pyrolysis module is connected to the solar thermal energy storage system and is used to receive the heat energy output by the solar thermal energy storage system to pyrolyze the carbon-based fuel to form gaseous volatile matter and solid semicoke; the volatile matter upgrading pyrolysis module is respectively connected to the raw material pyrolysis module and the photovoltaic energy storage system and is used to receive the heat energy output by the photovoltaic energy storage system to perform deep pyrolysis reaction on the gaseous volatile matter to obtain syngas; the solid coke separate utilization module is connected to the raw material pyrolysis module and is connected to the photovoltaic energy storage system and is used to receive the electrical energy output by the photovoltaic energy storage system to perform solid coke separate utilization on the solid semicoke to obtain at least one of high-purity semicoke, low-boiling point substances, and high-boiling point substances.

[0031] Specifically, the carbon-based fuel fractionation conversion system of the present invention has core components including a photovoltaic thermal energy storage system, a solar thermal energy storage system, a raw material pyrolysis module, a volatile matter upgrading pyrolysis module, and a solid coke fractionation utilization module, etc. Among them, the raw material pyrolysis module can be a pyrolysis reactor, the volatile matter upgrading pyrolysis module includes a high-temperature fluidized bed reactor, and the solid coke fractionation utilization module includes purification furnaces (medium temperature and ultra-high temperature), etc. These components work together to drive the entire carbon-based fuel conversion process using solar energy. Among them, both the solar thermal energy storage system and the photovoltaic thermal energy storage system are connected or linked to the fractionation conversion system, and provide the main heat required for the reaction for other modules in a direct or indirect manner through solar energy.

[0032] The photovoltaic thermal energy storage system can convert solar energy into electrical energy through photovoltaic devices / components. The photovoltaic components mainly provide power support for the electric heating device and the purification furnace. The photovoltaic components efficiently convert sunlight into electrical energy, and after obtaining the electrical energy, it is stored or directly used for electro-thermal conversion to generate heat energy. The stored electrical energy can directly supply power to devices that use electric heating methods such as the electric heating device and the purification furnace, meeting the electrical energy requirements of the reactors and heating systems that need to be heated. In some embodiments, the electrical energy is converted into heat energy through the electric heating device to provide heat for reactors that require non-electric heating in the subsequent process (such as high-temperature fluidized bed reactors).

[0033] The solar thermal energy storage system is used to receive sunlight and perform solar-thermal conversion, obtain heat energy and store it for subsequent use. For example, a solar concentrating system is used to concentrate sunlight and store the solar energy output by sunlight to obtain a stable high-temperature heat source, providing heat energy for the carbon-based fuel in the raw material pyrolysis module that requires non-electric heating.

[0034] The fractionation conversion system is composed of a raw material pyrolysis module, a volatile matter upgrading pyrolysis module, and a solid coke fractionation utilization module. The raw material pyrolysis module can specifically be a pyrolysis reactor, and more specifically, any one or combination of a fluidized bed, a downer bed, a moving bed, and a fixed bed is adopted. The pyrolysis reactor can achieve high-temperature pyrolysis reactions and ensure the stability of the pyrolysis process. In the specific implementation process, a carbon-based fuel can be introduced into the pyrolysis reactor. Therefore, the pyrolysis reactor can use the heat generated by the solar thermal energy storage system to perform a preliminary pyrolysis reaction on the carbon-based fuel input into the pyrolysis reactor at 400 - 800 °C, forming gaseous volatile matter and solid semi-coke.

[0035] In an alternative embodiment, the carbon-based fuel includes any one or combination of coal, biomass, waste plastics, and liquid hydrocarbons.

[0036] In an alternative embodiment, by flexibly selecting different types of carbon-based fuels and pyrolysis reactors, it is possible to adapt to various raw materials and reaction conditions in different industrial scenarios.

[0037] The volatile matter upgrading pyrolysis module receives the gaseous volatile matter from the raw material pyrolysis module and the thermal energy converted by the photovoltaic energy storage system, and further deeply cracks it by using the thermal energy provided by the photovoltaic energy storage system. In some embodiments, the volatile matter upgrading pyrolysis module may specifically be a high-temperature fluidized bed reactor. In the specific implementation process, the gaseous volatile matter coming out of the pyrolysis reactor is input here, and with the heat provided by the photovoltaic system, it is secondarily cracked at 1100-1600 °C to generate syngas.

[0038] In this embodiment, multi-stage pyrolysis and separate utilization of substances are adopted, which can increase the proportion of hydrogen and syngas in the gaseous volatile matter.

[0039] The solid coke separate utilization module receives the solid semi-coke from the raw material pyrolysis module and is connected to the photovoltaic energy storage system. It can directly use the electric energy output by the photovoltaic energy storage system to further decompose the solid semi-coke, respectively obtaining low-boiling point substances, high-purity semi-coke, and high-boiling point substances.

[0040] In this embodiment, syngas, high-purity semi-coke, low-boiling point substances, and high-boiling point substances are all used as the target products of this system. Syngas is used as product 1, low-boiling point substances are used as product 2, high-purity semi-coke is used as product 3, and high-boiling point substances are used as product 4, and they are collected for different uses.

[0041] In summary, for the system provided in the embodiments of this application, the solar-thermal energy storage system and the photovoltaic energy storage system are cleverly coupled and used, and solar energy is used to provide the heat required for the reaction for other modules (raw material pyrolysis module, volatile matter upgrading pyrolysis module, and solid coke separate utilization module) for the fractional conversion of carbon-based fuels. Through the synergistic effect of photovoltaic and solar-thermal energy, the energy utilization efficiency is effectively improved, the high-efficiency conversion of carbon-based fuels is realized, the dependence on traditional fossil energy is greatly reduced, carbon dioxide emissions are reduced, and low-carbon emissions are achieved.

[0042] In addition, all the heat of this system is only provided by the photovoltaic energy storage system and the solar-thermal energy storage system, realizing the efficient conversion of carbon-based fuels driven by solar energy. This system is applicable to the fractional conversion of carbon-based fuels such as coal, biomass, and waste plastics, and can obtain high-value-added products such as syngas, low-boiling point gases, and high-purity semi-coke, meeting the requirements of low-carbon economy, and having broad application prospects in the fields of clean energy, waste resource utilization, and syngas production.

[0043] This embodiment is used to illustrate the specific manner in which a solar thermal energy storage system receives sunlight and performs solar-thermal conversion to obtain thermal energy. The solar thermal energy storage system includes a solar thermal device, a first high-temperature heat storage tank, a first low-temperature heat storage tank, and solid particles; wherein, the first high-temperature heat storage tank is respectively connected to the solar thermal device and the raw material pyrolysis module; the first low-temperature heat storage tank is respectively connected to the solar thermal device and the raw material pyrolysis module; the solid particles circulate between the solar thermal device, the first high-temperature heat storage tank, the raw material pyrolysis module, and the first low-temperature heat storage tank.

[0044] In this embodiment, the solar thermal energy storage system includes a solar thermal device, a first high-temperature heat storage tank, a first low-temperature heat storage tank, and solid particles. The solar thermal device focuses sunlight and converts it into thermal energy, which is transferred to the solid particles. After the solid particles are heated, they are stored in the first high-temperature heat storage tank to provide a stable heat source. During the pyrolysis process, the heat-stored solid particles transfer heat to the carbon-based fuel and ensure that the temperature is within the required reaction range.

[0045] Specifically, the solar thermal device can adopt a heliostat focusing technology (such as a Fresnel lens, a parabolic concentrator, or a tower solar thermal reaction device) to focus and collect sunlight heat, and transfer it to the low-temperature solid particles transported from the first low-temperature heat storage tank, heating the low-temperature solid particles to a high-temperature state to make them hot particles, completing the solar-thermal conversion.

[0046] The outlet of the solar thermal device is connected to the inlet of the first high-temperature heat storage tank through a pipeline. After the low-temperature solid particles are heated to above 800 °C, they are transported to the first high-temperature heat storage tank for storage to ensure the continuous supply of thermal energy. The outlet of the first high-temperature heat storage tank is connected to the inlet of the pyrolysis reactor through a pipeline. The high-temperature solid particles are continuously transported from the first high-temperature heat storage tank to the pyrolysis reactor and transfer heat to the carbon-based fuel.

[0047] The outlet of the pyrolysis reactor is connected to the inlet of the first low-temperature heat storage tank through a pipeline. After the temperature of the high-temperature solid particles drops below 400 °C, the low-temperature solid particles released by the pyrolysis reactor are recovered and stored through the first low-temperature heat storage tank. The outlet of the first low-temperature heat storage tank is connected to the inlet of the solar thermal device through a pipeline, so as to send the low-temperature solid particles back into the solar thermal device through the pipeline again to complete the circulation of the solid particles.

[0048] Preferably, the solid particles are any one of quartz sand, ceramics, and alumina. The heat transfer system of the solid particles makes the energy utilization more efficient and reduces energy consumption and environmental impact.

[0049] As an alternative to this embodiment, the outlet of the solar thermal device is connected to the inlet of the first high-temperature heat storage tank. The outlet of the first high-temperature heat storage tank is connected to the inlet of the pyrolysis reactor through a gas pipeline. The outlet of the first high-temperature heat storage tank is connected to the inlet of the first low-temperature heat storage tank, and the outlet of the first low-temperature heat storage tank is connected to the solar thermal device. Therefore, the high-temperature solid particles in the first high-temperature heat storage tank are not transported, but are directly transported to the first low-temperature heat storage tank after heat exchange with the heat exchange gas (such as air). The high-temperature air after heat exchange with the high-temperature solid particles is transported to the pyrolysis reactor and transfers heat to the carbon-based fuel.

[0050] This embodiment is used to illustrate the specific ways in which the photovoltaic-thermal energy storage system receives sunlight, performs photovoltaic conversion to obtain electric energy, and performs electro-thermal conversion on the electric energy to obtain thermal energy. The photovoltaic-thermal energy storage system includes: a photovoltaic device for converting the light energy output by sunlight into electric energy; an electric heating device with heat carrier particles flowing inside and connected to the photovoltaic device for receiving electric energy to heat the heat carrier particles; a second high-temperature heat storage tank connected to the electric heating device for receiving and storing the heated heat carrier particles; the second high-temperature heat storage tank is connected to the volatile matter upgrading and pyrolysis module for transferring the heat of the heat carrier particles to the gaseous volatile matter; a second low-temperature heat storage tank connected to the volatile matter upgrading and pyrolysis module and the electric heating device respectively for receiving and storing the heat carrier particles after heat transfer and returning the heat carrier particles to the electric heating device.

[0051] In this embodiment, the photovoltaic device uses common photovoltaic modules, which are responsible for converting sunlight into electric energy and providing power for the electric heating device and the subsequent purification furnace. After the photovoltaic device converts sunlight into electric energy, it supplies power to the electric heating device, so that the heat carrier particles transported from the second low-temperature heat storage tank are heated to above 1600 °C, converting electric energy into thermal energy. The outlet of the electric heating device is connected to the inlet of the second high-temperature heat storage tank, and the high-temperature heat carrier particles heated by the electric heating device are transported to the second high-temperature heat storage tank for storage. The outlet of the second high-temperature heat storage tank is connected to the inlet of the fluidized bed heat exchanger of the volatile matter upgrading and pyrolysis module. The high-temperature heat carrier particles are in full contact with the gaseous volatile matter, transferring heat to the gaseous volatile matter and causing it to undergo deep cracking to obtain syngas. The outlet of the fluidized bed heat exchanger is connected to the inlet of the second low-temperature heat storage tank, and the outlet of the second low-temperature heat storage tank is connected to the inlet of the electric heating device, completing the cycle of the heat carrier particles.

[0052] In summary, by using this solar-thermal energy storage system, with solid particles and heat carriers as the heat carriers, through the coordinated action of the high-temperature heat storage tank and the low-temperature heat storage tank, the efficient storage and utilization of solar energy are realized, the surplus solar energy resources are effectively absorbed, the sustainability of energy is improved, the efficient and stable supply of solar thermal energy is achieved, and the pyrolysis efficiency of carbon-based fuels is effectively improved.

[0053] In some embodiments, the first high-temperature heat storage tank and the second high-temperature heat storage tank are made of heat-insulating materials or are sleeved with heat-insulating layers on the outer periphery, which can effectively reduce heat loss.

[0054] This embodiment is used to illustrate a form of the volatile matter upgrading and pyrolysis module. The volatile matter upgrading and pyrolysis module is a high-temperature fluidized bed, and the high-temperature fluidized bed is respectively connected to the raw material pyrolysis module, the second high-temperature heat storage tank and the second low-temperature heat storage tank. In this embodiment, the gaseous volatile matter can be directly input into the high-temperature fluidized bed to contact with the high-temperature heat carrier particles to complete secondary pyrolysis.

[0055] This embodiment is used to illustrate another form of the volatile matter upgrading and pyrolysis module. The volatile matter upgrading and pyrolysis module includes a tar separation device and a high-temperature fluidized bed. The tar separation device is connected to the raw material pyrolysis module, and the high-temperature fluidized bed is respectively connected to the tar separation device, the second high-temperature heat storage tank and the second low-temperature heat storage tank. In this embodiment, the gaseous volatile matter first enters the tar separation device for pretreatment to remove most of the tar, and then the gaseous volatile matter after tar separation is input into the high-temperature fluidized bed to contact with the high-temperature heat carrier particles to complete secondary pyrolysis. Among them, the separated tar goes to the tar deep processing section.

[0056] Thus, the embodiments of the present invention are applicable to the treatment of low-tar raw materials with low tar content such as bituminous coal and anthracite, as well as the treatment of high-tar raw materials such as corn straw, rice husk and lignite.

[0057] This embodiment is used to illustrate the solid coke quality utilization module. The solid coke quality utilization module includes: a first purification furnace, connected to the raw material pyrolysis module, for receiving and purifying solid semicoke to form ash-containing semicoke and low-boiling gaseous recovery products; a second purification furnace, connected to the first purification furnace, for receiving and purifying the ash-containing semicoke to form high-boiling gaseous recovery products and obtaining high-purity semicoke; wherein, both the first purification furnace and the second purification furnace are connected to the photovoltaic device to be powered and heated by the photovoltaic device; the solid coke quality utilization module further includes: a first condensation recovery device, connected to the first purification furnace, for receiving and condensing the low-boiling gaseous recovery products to obtain low-boiling substances; a second condensation recovery device, connected to the second purification furnace, for receiving and condensing the high-boiling gaseous recovery products to obtain high-boiling substances.

[0058] In this embodiment, the first purification furnace and the second purification furnace are respectively used for purifying semicoke. The first purification furnace is a medium-temperature purification furnace. In the medium-temperature purification furnace, the solid semicoke is fluidized and purified at a temperature of 1000-1500 °C, and low-boiling substances are by-produced during the purification of semicoke. Specifically, the first condensation recovery device is used to condense the low-boiling gaseous recyclate generated by the first purification furnace, and the low-boiling substances are recovered. The second purification furnace is an ultra-high-temperature purification furnace. In the ultra-high-temperature purification furnace, the semicoke is purified at a temperature above 2500 °C to generate high-purity semicoke, and high-boiling substances are by-produced. Specifically, the second condensation recovery device is used to condense the high-boiling gaseous recyclate generated by the second purification furnace, and the high-boiling substances are extracted.

[0059] Among them, both the medium-temperature purification furnace and the ultra-high-temperature purification furnace adopt an electric heating method for heat supply, and the electric energy is sourced from the above-mentioned photovoltaic device.

[0060] In this way, the solid coke fractionation utilization module of the embodiment of the present invention adopts a two-stage purification and condensation recovery method to gradually purify the solid semicoke. Combined with photovoltaic electric heating, various products are fractionally recovered, ensuring the high purity of each product and realizing product diversification.

[0061] Correspondingly, for the second aspect, please refer to Figure 2 as shown in Figure 2 which is a flowchart of the steps of a carbon-based fuel fractional conversion method based on photovoltaic-thermal coupling. The present invention also provides a carbon-based fuel fractional conversion method based on photovoltaic-thermal coupling, which is used in the carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling provided in the first aspect of the present invention. It includes solar energy utilization, raw material pyrolysis, volatile matter upgrading pyrolysis, and solid coke fractional utilization. The method includes the following steps: S1. Use the photovoltaic-thermal energy storage system to receive sunlight and perform photovoltaic-thermal conversion to obtain thermal energy.

[0062] Further, step S1 includes: S11. Transport the solid particles in the first low-temperature energy storage tank to the photovoltaic-thermal device; S12. Use the photovoltaic-thermal device to focus sunlight on the solid particles therein and heat the solid particles; S13. Transport the heated solid particles to the first high-temperature energy storage tank for storage. Among them, after the solid particles are heated to above 800 °C, they are transported to the high-temperature energy storage tank for storage.

[0063] Alternatively, step S1 includes: S101. Transport the solid particles in the first low-temperature energy storage tank to the photovoltaic-thermal device; S102. Use the photovoltaic-thermal device to focus sunlight on the solid particles therein and heat the solid particles; S103. Transfer the heated solid particles into the first high-temperature heat storage tank, and conduct heat exchange between the solid particles and the heat exchange gas; S104. Return the heat-exchanged solid particles to the first low-temperature heat storage tank.

[0064] S2. Use the photovoltaic heat storage system to receive sunlight and perform photovoltaic conversion to obtain electric energy, and perform electro-thermal conversion on the electric energy to obtain heat energy.

[0065] Further, step S2 includes: S21. Use the photovoltaic device to convert sunlight into electric energy and directly supply power to the solid coke medium utilization module and the electric heating device; S22. Transport the heat carrier particles in the second low-temperature heat storage tank into the electric heating device; S23. Use the electric heating device to heat the heat carrier particles therein; after the photovoltaic device converts sunlight into electric energy, it supplies power to the electric heating device, so that the heat carrier transported from the second low-temperature heat storage tank is heated to above 1600 °C.

[0066] S24. Transport the heated heat carrier particles into the second high-temperature heat storage tank for storage, and complete the electro-thermal conversion.

[0067] S3. Use the raw material pyrolysis module to receive the heat energy and carbon-based fuel output by the solar thermal storage system, and perform pyrolysis reaction on the carbon-based fuel to form gaseous volatiles and solid semi-coke; the temperature of the pyrolysis reaction is 400-800 °C, and the solar energy is used by the solar thermal storage system to preliminarily pyrolyze the carbon-based fuel, laying a foundation for the subsequent pyrolysis process.

[0068] In this embodiment, according to the two solar thermal storage methods in step S1 above, step S3 correspondingly includes two pyrolysis methods.

[0069] In the first method, the solid particles in step S13 are continuously transported from the first high-temperature heat storage tank to the pyrolysis reactor, transfer heat to the carbon-based fuel, and then are transported to the first low-temperature heat storage tank in step S11 after the temperature drops below 400 °C, completing the cycle of solid particles. That is, step S3 is: S31. Transport the solid particles and carbon-based fuel in the first high-temperature heat storage tank into the raw material pyrolysis module, and transfer the heat of the solid particles to the carbon-based fuel, so that the carbon-based fuel undergoes a pyrolysis reaction; S32. Transport the heat-transferred solid particles into the first low-temperature heat storage tank in step S11 for storage.

[0070] In Method 2, the solid particles in the first high-temperature heat storage tank in Step S13 are not conveyed, but enter Step S103, enabling the high-temperature solid particles entering the first high-temperature heat storage tank to exchange heat with the air therein. The low-temperature solid particles after heat exchange are directly conveyed to the first low-temperature heat storage tank; the high-temperature air after heat exchange is conveyed to the pyrolysis reactor in Step S3 and transfers heat to the carbon-based fuel. That is, Step S3 is as follows: S301. Convey the heat exchange gas after heat exchange and the carbon-based fuel into the raw material pyrolysis module, and the heat of the heat exchange gas is transferred to the carbon-based fuel, causing the carbon-based fuel to undergo a cracking reaction.

[0071] In an optional embodiment, when the pyrolysis reaction is carried out in Step S3, optionally, a pyrolysis aid is introduced into the pyrolysis reactor; the pyrolysis aid is any one or a combination of water vapor, oxygen, hydrogen, and methane. Adding a pyrolysis aid can significantly improve the efficiency of the pyrolysis reaction and improve the product distribution, especially playing an important role in controlling the reaction temperature and gas composition.

[0072] S4. Input the gaseous volatiles into the volatile matter upgrading pyrolysis module, and use the heat energy generated by the photovoltaic heat storage system to carry out a deep cracking reaction on the gaseous volatiles to obtain syngas.

[0073] Among them, the heat carrier particles in Step S24 are continuously conveyed from the second high-temperature heat storage tank into the high-temperature fluidized bed, transfer heat to the gaseous volatiles, and then are conveyed into the second low-temperature heat storage tank in Step S22 after the temperature drops below 400°C, completing the circulation of the heat carrier particles.

[0074] Specifically, the gaseous volatiles generated in S1 are input into the high-temperature fluidized bed after being separated from tar or directly, and are further heated and cracked at 1100 - 1600°C using the heat generated by the photovoltaic heat storage system to form syngas. This step uses the high-temperature fluidized bed to deeply crack the volatiles to improve the gas conversion efficiency of the products and ensure the efficient generation of the required gas products.

[0075] In an optional embodiment, the total volume ratio of CO and H2 in the syngas in Step S4 is not less than 85%; the ratio of CO:H2 is 1:1 - 2:1. The high quality and reasonable ratio of the syngas will directly affect the efficiency of the subsequent chemical synthesis process, especially in applications such as synthetic fuels and chemicals.

[0076] S5. Input the solid semicoke into the solid coke quality utilization module, and use the electric energy generated by the photovoltaic heat storage system to carry out solid coke quality utilization on the solid semicoke to obtain at least one of high-purity semicoke, low-boiling point substances, and high-boiling point substances.

[0077] Furthermore, Step S5 includes: S51. Input the solid semicoke into the first purification furnace, and utilize the electric energy provided by the photovoltaic device to fluidize and purify the solid semicoke in an inert atmosphere to form low-boiling gaseous recyclables and ash-containing semicoke; S52. Transfer the low-boiling gaseous recyclables to the first condensation recovery device, and obtain low-boiling substances through condensation recovery; S53. Transfer the ash-containing semicoke to the second purification furnace, and utilize the electric energy provided by the photovoltaic device to purify it in an inert atmosphere to form high-boiling gaseous recyclables and obtain high-purity semicoke; S54. Transfer the high-boiling gaseous recyclables to the second condensation recovery device, and obtain high-boiling substances after condensation recovery.

[0078] Specifically, input the solid semicoke generated in S3 into the medium-temperature purification furnace, and fluidize and purify it in an inert atmosphere at 1000 - 1500 °C to form low-boiling gaseous recyclables and ash-containing semicoke; the low-boiling gaseous recyclables are processed through condensation recovery to form low-boiling substances. Further, input the ash-containing semicoke into the ultra-high-temperature purification furnace, and purify it in an inert atmosphere above 2500 °C to form high-boiling gaseous recyclables and obtain high-purity semicoke; the high-boiling gaseous recyclables are obtained high-boiling substances after condensation recovery.

[0079] This step focuses on solving the impurity problem in the solid semicoke, and realizes multi-stage purification through purification furnaces at different temperatures, enabling the separate recovery of various products and ensuring the high purity of each product.

[0080] In an alternative embodiment, the medium-temperature purification furnace and the ultra-high-temperature purification furnace in step S5 can adopt intermittent operation or continuous operation modes.

[0081] In an alternative embodiment, the low-boiling substances include NaCl, KCl, asphaltene, heavy aromatics, and polycyclic aromatic hydrocarbons. The high-boiling substances include Al2O3, SiO2, CaO, MgO, Hg, Pb, and Cd. The components and purities of the low-boiling substances and the high-boiling substances depend on the specific methods of condensation recovery processing in step S5. The purity of the high-purity semicoke is not less than 99.9%.

[0082] It should be noted that for the method embodiments, the embodiments of the present application are not limited by the described order of actions, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously.

[0083] The features and properties of the present invention will be further described in detail below in conjunction with specific embodiments.

[0084] Example 1 The main objective of this embodiment is to obtain syngas and high-purity semicoke through the fractional conversion of coal by pyrolysis, while by-products such as low-boiling substances (NaCl, KCl, asphaltene, heavy aromatics, polycyclic aromatic hydrocarbons, etc.) and high-boiling substances (Al2O3, SiO2, CaO, MgO, Hg, Pb, Cd, etc.) are produced. This process combines a fluidized bed reactor with a high-temperature heat source provided by a solar-thermal energy storage system to effectively improve the conversion efficiency of coal, minimize carbon emissions to the greatest extent, and recover valuable by-products with different boiling points.

[0085] First, the coal raw material is fed into the fluidized bed cracking reactor through a hopper, and the heat is transferred by hot air that has been heat-exchanged with the high-temperature solid particles of the solar-thermal energy storage system in the pyrolysis reactor. The temperature in the reactor is controlled at 650 °C for coal pyrolysis, and gaseous volatiles and solid semicoke are generated by cracking.

[0086] Second, the gaseous volatiles after pyrolysis are processed by a high-temperature fluidized bed reactor at a temperature maintained at 1350 °C, and the heating source is provided by a photovoltaic system to generate syngas (such as Figure 1 Product 1), where the ratio of CO:H2 is 1:1.5, and the total proportion of CO and H2 in the syngas is 85%.

[0087] Finally, the residual semicoke is fed into a medium-temperature purification furnace and purified at 1200 °C to generate low-boiling gases, which are recovered as low-boiling substances (including NaCl, KCl, asphaltene, heavy aromatics, polycyclic aromatic hydrocarbons, such as Figure 1 Product 2) through stepwise condensation. The further semicoke is processed in an ultra-high-temperature furnace at 2500 °C to produce high-boiling substances (including Al2O3, SiO2, CaO, MgO, Hg, Pb, Cd, such as Figure 1 Product 4), and these substances are recovered through a condensation device to obtain a higher-purity product. The purified metallurgical coke (such as Figure 1 Product 3) has a purity of 99.9% and is suitable for the metallurgical industry.

[0088] This embodiment has successfully achieved the fractional conversion of coal, recovered high-purity syngas and high-purity semicoke, and recovered low-boiling substances and high-boiling substances through condensation and cyclone separation. The implementation of this process reduces carbon emissions and improves the comprehensive utilization efficiency of resources at the same time.

[0089] Example 2 The main objective of this embodiment is to obtain syngas as the main product through the thermal cracking and medium conversion of waste plastics, while by-products such as low-boiling substances (asphaltenes, heavy aromatics, polycyclic aromatic hydrocarbons) and high-purity semicoke are produced, and high-boiling substances (such as filler residues, metal oxides, and metal elements in waste plastics) are directly removed. The pyrolysis reactor for this process uses a downer reactor, combined with the high-temperature heat source provided by the solar-thermal energy storage system, which can effectively improve the conversion efficiency of waste plastics, minimize carbon emissions to the greatest extent, and recover valuable by-products with different boiling points.

[0090] First, the waste plastics are fed into the downer pyrolysis reactor through a hopper, and hot air that has been heat-exchanged with high-temperature solid particles from the solar-thermal energy storage system is introduced into the reactor to transfer heat. The reactor temperature is controlled at 450 °C for pyrolysis, and the waste plastics are cracked to generate gaseous volatiles and solid semicoke. The reactor is equipped with a double-layer structure, with the inner layer being a heat-insulating layer to ensure efficient heat transfer.

[0091] Second, the gaseous volatiles after pyrolysis are processed through a high-temperature fluidized bed reactor. The temperature is set at 1350 °C, and the heating source is provided by the photovoltaic system, generating syngas (such as Figure 1 Product 1), where the CO:H2 ratio is 1:1.4, and the total proportion of CO and H2 in the syngas is 89%.

[0092] Finally, the residual semicoke is fed into a medium-temperature purification furnace and purified at 1200 °C to generate low-boiling substances (including asphaltenes, heavy aromatics, polycyclic aromatic hydrocarbons, such as Figure 1 Product 2), and these substances are recovered through stepwise condensation. The purified semicoke is further processed in an ultra-high-temperature furnace at 2500 °C to generate high-boiling substances (including Fe, Al, and filler residues). The purified semicoke (such as Figure 1 Product 3) has a purity of 99.98% and is suitable for use as a catalytic support.

[0093] This embodiment obtains syngas and high-purity semicoke through the efficient thermal cracking conversion of waste plastics, recovers low-boiling substances through condensation and separation, and removes high-boiling substances. This process can reduce the environmental pollution of waste plastics, improve the comprehensive utilization efficiency of resources, and effectively reduce carbon emissions.

[0094] Example 3 The main objective of this embodiment is to obtain syngas and high-purity semicoke through the pyrolysis and fractionation conversion of biomass fuel, while by-products such as low-boiling substances (including NaCl, KCl, asphaltene, heavy aromatics, polycyclic aromatic hydrocarbons, etc.) and high-boiling substances (including Al2O3, SiO2, CaO, MgO, Hg, Pb, Cd) are produced. The pyrolysis reactor for this process adopts the form of a fixed bed and combines with a solar-thermal energy storage system to obtain a high-temperature heat source, which can effectively improve the conversion efficiency of biomass fuel, minimize carbon emissions to the greatest extent, and recover valuable by-products with different boiling points.

[0095] First, the biomass fuel is fed into the fixed-bed pyrolysis reactor through a hopper, and the heat is transferred inside the reactor by high-temperature solid particles provided by the solar-thermal energy storage system. The reactor temperature is controlled at 550 °C for pyrolysis. During pyrolysis, steam is introduced into the pyrolysis reactor as a pyrolysis aid, and the biomass fuel is cracked to generate gaseous volatiles and solid semicoke.

[0096] Second, the gaseous volatiles after pyrolysis are processed by a high-temperature fluidized-bed reactor. The temperature is set at 1350 °C, and the heating source is provided by a photovoltaic system to generate syngas (such as Figure 1 Product 1), where the ratio of CO:H2 is 1:1.6, and the total proportion of CO and H2 in the syngas is 91%.

[0097] Finally, the residual semicoke is fed into a medium-temperature purification furnace and purified at 1200 °C to generate low-boiling substances (including NaCl, KCl, asphaltene, heavy aromatics, polycyclic aromatic hydrocarbons, such as Figure 1 Product 2), and these substances are recovered by stepwise condensation. The purified semicoke is then further processed in an ultra-high-temperature furnace at 2500 °C to generate high-boiling substances (including Al2O3, SiO2, CaO, MgO, Hg, Pb, Cd, such as Figure 1 Product 4). These substances are recovered by a condensation device to finally obtain a product with higher purity. The purified high-purity semicoke (such as Figure 1 Product 3) has a purity of 99.99% and is widely used in the battery industry.

[0098] This embodiment has successfully achieved the efficient conversion of biomass fuel, obtained syngas and high-purity semicoke, and recovered low-boiling substances and high-boiling substances through condensation and cyclone separation. This process not only improves the resource utilization efficiency, reduces the environmental burden of waste biomass, but also effectively reduces carbon emissions.

[0099] The above three embodiments all apply the green power-driven fluidized-bed heating system of the present invention, which provides a sustainable high-temperature air supply for high-temperature industrial processes such as the metallurgy, cement, and chemical industries through electric heating elements, particle energy storage technology, and an efficient heat recovery mechanism, and effectively solves the challenges of energy supply and carbon emissions.

[0100] For the above method embodiments, since they are basically similar to the system embodiments, the description is relatively simple. For the relevant parts, please refer to the corresponding descriptions in the system embodiments.

[0101] It should be noted that the embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0102] It should also be noted that in this text, the orientation or positional relationships indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations, nor can they be construed as indicating or implying relative importance. Moreover, the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or terminal device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or terminal device.

Claims

1. A carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling, characterized in that, The system includes: A solar thermal energy storage system for receiving sunlight and performing solar-thermal conversion to obtain thermal energy; A photovoltaic energy storage system for receiving sunlight and performing photovoltaic conversion to obtain electrical energy, and performing electro-thermal conversion on the electrical energy to obtain thermal energy; A medium-separated conversion system, including a raw material pyrolysis module, a volatile matter upgrading pyrolysis module, and a solid coke medium-separated utilization module. The raw material pyrolysis module is used to receive a carbon-based fuel. Among them, The raw material pyrolysis module is connected to the solar thermal energy storage system and is used to receive the thermal energy output by the solar thermal energy storage system to cause the carbon-based fuel to undergo a pyrolysis reaction to form gaseous volatile matter and solid semicoke; The volatile matter upgrading pyrolysis module is respectively communicated with the raw material pyrolysis module and the photovoltaic energy storage system, and is used to receive the thermal energy output by the photovoltaic energy storage system to perform a deep pyrolysis reaction on the gaseous volatile matter to obtain syngas; The solid coke medium-separated utilization module is communicated with the raw material pyrolysis module and is connected to the photovoltaic energy storage system, and is used to receive the electrical energy output by the photovoltaic energy storage system to perform solid coke medium-separated utilization on the solid semicoke to obtain at least one of high-purity semicoke, low-boiling-point substances, and high-boiling-point substances.

2. The carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 1, wherein The solar thermal energy storage system includes a solar thermal device, a first high-temperature heat storage tank, a first low-temperature heat storage tank, and solid particles. Among them, the first high-temperature heat storage tank is respectively communicated with the solar thermal device and the raw material pyrolysis module; the first low-temperature heat storage tank is respectively communicated with the solar thermal device and the raw material pyrolysis module; the solid particles circulate among the solar thermal device, the first high-temperature heat storage tank, the raw material pyrolysis module, and the first low-temperature heat storage tank.

3. A carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 1, characterized in that, The solar thermal energy storage system includes a solar thermal device, a first high-temperature heat storage tank, a first low-temperature heat storage tank, solid particles, and a heat exchange gas. Among them, the first high-temperature heat storage tank is respectively communicated with the solar thermal device and the raw material pyrolysis module; the first low-temperature heat storage tank is respectively communicated with the solar thermal device and the first high-temperature heat storage tank; the solid particles circulate among the solar thermal device, the first high-temperature heat storage tank, and the first low-temperature heat storage tank, and the heat exchange gas flows from the first high-temperature heat storage tank to the raw material pyrolysis module.

4. A carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling according to claim 2 or 3, characterized in that The solid particles include any one of quartz sand, ceramics, and alumina.

5. A carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 1, characterized in that, The photovoltaic energy storage system includes: A photovoltaic device for converting the light energy output by the sunlight into electrical energy; An electric heating device with heat carrier particles flowing inside and connected to the photovoltaic device, and is used to receive the electrical energy to heat the heat carrier particles; A second high-temperature heat storage tank communicated with the electric heating device, and is used to receive and store the heated heat carrier particles; the second high-temperature heat storage tank is communicated with the volatile matter upgrading pyrolysis module, and is used to transfer the heat of the heat carrier particles to the gaseous volatile matter; A second low-temperature heat storage tank respectively communicated with the volatile matter upgrading pyrolysis module and the electric heating device, and is used to receive and store the heat carrier particles after heat transfer and send the heat carrier particles back to the electric heating device.

6. The carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 1, wherein The raw material thermal cracking module is a pyrolysis reactor; wherein the pyrolysis reactor includes any one or a combination of a fluidized bed, a descending bed, a moving bed and a fixed bed.

7. A carbon-based fuel fractional conversion system based on photovoltaic-thermal coupling according to claim 5, characterized in that, The volatile matter upgrading pyrolysis module is a high-temperature fluidized bed, and the high-temperature fluidized bed is respectively connected to the raw material thermal cracking module, the second high-temperature heat storage tank and the second low-temperature heat storage tank; Alternatively, the volatile matter upgrading pyrolysis module includes a tar separation device and a high-temperature fluidized bed, the tar separation device is connected to the raw material thermal cracking module, and the high-temperature fluidized bed is respectively connected to the tar separation device, the second high-temperature heat storage tank and the second low-temperature heat storage tank.

8. A carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 5, characterized in that The solid coke quality-based utilization module comprises: a first purification furnace, connected to the raw material thermal cracking module, for receiving and purifying the solid semi-coke to form ash-containing semi-coke and low-boiling-point gaseous recovered products; A second purification furnace, connected to the first purification furnace, is used to receive and purify the ash-containing semi-coke to form a high-boiling point gaseous recovery product and obtain high-purity semi-coke; Wherein, the first purification furnace and the second purification furnace are both connected to the photovoltaic device to be powered and heated by the photovoltaic device; the solid coke fractionation and utilization module further includes: a first condensation recovery device, connected to the first purification furnace, for receiving and condensing the low-boiling point gaseous recovery to obtain a low-boiling point substance; The second condensation recovery device is connected to the second purification furnace and is used for receiving and condensing the high-boiling-point gaseous recovery to obtain high-boiling-point substances.

9. The carbon-based fuel fractionation conversion system based on photovoltaic-thermal coupling according to claim 1, characterized in that, The carbon-based fuel includes any one or a combination of coal, biomass, waste plastics and liquid hydrocarbons.

10. A method for the separate conversion of carbon-based fuels based on photovoltaic-thermal coupling, characterized in that, Relying on the carbon-based fuel mass conversion system based on photovoltaic and thermal coupling as described in any one of claims 1 to 9 for mass conversion, the method comprises: S1. Utilize a photothermal heat storage system to receive sunlight and convert it into thermal energy; S2, using a photovoltaic heat storage system to receive sunlight and perform photoelectric conversion to obtain electrical energy, and performing electrothermal conversion on the electrical energy to obtain thermal energy; S3, using a raw material pyrolysis module to receive the heat energy and carbon-based fuel output by the photothermal heat storage system, so as to cause the carbon-based fuel to undergo pyrolysis reaction to form gaseous volatiles and solid semi-coke; S4, inputting the gaseous volatiles into a volatile upgrading pyrolysis module, and using the heat energy generated by the photovoltaic heat storage system to perform a deep cracking reaction on the gaseous volatiles to obtain synthesis gas; S5. Input the solid semi-coke into a solid coke fractionation and utilization module, and utilize the electric energy generated by the photovoltaic thermal storage system to perform solid coke fractionation and utilization on the solid semi-coke to obtain at least one of high-purity semi-coke, low-boiling-point substances and high-boiling-point substances.

11. A method for separating and converting carbon-based fuels based on photovoltaic-thermal coupling according to claim 10, characterized in that, Step S1 includes: S11, transporting the solid particles in the first low-temperature heat storage tank to the photothermal device; S12, using a photothermal device to focus sunlight on solid particles therein, thereby heating the solid particles; S13, transferring the heated solid particles to a first high-temperature heat storage tank for storage; Step S3 includes: S31. Transport the solid particles and carbon-based fuel in the first high-temperature heat storage tank into the raw material pyrolysis module. The heat of the solid particles is transferred to the carbon-based fuel, causing the carbon-based fuel to undergo a pyrolysis reaction. S32. Transport the heat-transferred solid particles into the first low-temperature heat storage tank in step S11 for storage.

12. A method for separating and converting carbon-based fuels based on photovoltaic-thermal coupling according to claim 10, characterized in that, Step S1 includes: S101. Transport the solid particles in the first low-temperature heat storage tank into the solar thermal device. S102. Use the solar thermal device to focus sunlight on the solid particles therein and heat the solid particles. S103. Transfer the heated solid particles into the first high-temperature heat storage tank, and allow the solid particles to exchange heat with the heat exchange gas. S104. Return the heat-exchanged solid particles to the first low-temperature heat storage tank. Step S3 includes: S301. Transport the heat-exchanged heat exchange gas and carbon-based fuel into the raw material pyrolysis module. The heat of the heat exchange gas is transferred to the carbon-based fuel, causing the carbon-based fuel to undergo a pyrolysis reaction.

13. A method for separating and converting carbon-based fuels based on photovoltaic-thermal coupling according to claim 10, characterized in that, Step S2 includes: S21. Use the photovoltaic device to convert sunlight into electrical energy and directly supply power to the solid coke medium utilization module and the electric heating device. S22. Transport the heat carrier particles in the second low-temperature heat storage tank into the electric heating device. S23. Use the electric heating device to heat the heat carrier particles therein. S24. Transfer the heated heat carrier particles into the second high-temperature heat storage tank for storage, completing the electro-thermal conversion. Step S4 includes: S41. Transport the heat carrier particles in the second high-temperature heat storage tank into the high-temperature fluidized bed. At the same time, transport the gaseous volatiles into the high-temperature fluidized bed after separating tar through the tar separation device or directly. The heat of the heat carrier particles is transferred to the gaseous volatiles, causing the gaseous volatiles to undergo a deep pyrolysis reaction. S42. Transport the heat-transferred heat carrier particles into the second low-temperature heat storage tank in step S22 for storage.

14. A method for separating and converting carbon-based fuels based on photovoltaic-thermal coupling according to claim 13, characterized in that Step S5 includes: S51. Input the solid semicoke into the first purification furnace, and use the electrical energy provided by the photovoltaic device to fluidize and purify the solid semicoke in an inert atmosphere to form low-boiling gaseous recovery products and ash-containing semicoke. S52. Transport the low-boiling gaseous recovery products into the first condensation recovery device, and obtain the low-boiling substances after condensation recovery. S53. Transport the ash-containing semicoke into the second purification furnace, and use the electrical energy provided by the photovoltaic device to purify it in an inert atmosphere to form high-boiling gaseous recovery products and obtain the high-purity semicoke. S54. Transport the high-boiling gaseous recovery products into the second condensation recovery device, and obtain the high-boiling substances after condensation recovery.

15. A method for the fractional conversion of carbon-based fuels based on the coupling of photovoltaic and solar thermal energy according to claim 10, characterized in that, When performing the pyrolysis reaction in step S3, introduce a pyrolysis aid into the raw material pyrolysis module. The pyrolysis aid is any one or a combination of water vapor, oxygen, hydrogen, and methane.

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