In-situ resource utilization system

Abstract

The invention relates to an in-situ resource utilization system, which comprises: an excavation unit, which is communicated with a processing unit and can excavate lunar soil and transport the lunar soil into the processing unit; the treatment unit is used for transporting the lunar soil and the molten alloy among the units of the in-situ resource utilization system; the power generation unit is communicated with the processing unit and is used for providing electric energy for the in-situ resource utilization system and heating the lunar soil to a molten state; the electrolysis unit is communicated with the power generation unit and the treatment unit and can electrolyze the molten lunar soil to generate oxygen and molten alloy; the gas treatment unit is communicated with the electrolysis unit and can separate, purify, liquefy and store oxygen; the metal processing unit communicates with the processing unit and can store the molten alloy; and the heat control unit is used for carrying out active heat control in a forced convection heat transfer mode of pumping fluid, collecting heat energy generated by the in-situ resource utilization system by using working fluid, and then discharging the collected heat energy in a radiation heat transfer mode.

Description

Technical Field

[0001] The invention relates to the field of deep space metallurgy and oxygen production, and in particular to an in-situ resource utilization system. Background Art

[0002] Existing exploration results have shown that the lunar surface has rich reserves of resources. Among them, the lunar soil contains rich oxygen and mineral resources such as Si, Fe, Al, and Ti. In addition, the moon itself has good location and environmental resources, including vacuum, deep cryogenics, and space radiation. An important part of the development and utilization of lunar resources is to identify, obtain and utilize the natural resources on the lunar surface to obtain useful products and services.

[0003] The main types of lunar minerals are basalt (pyroxene, ilmenite, olivine), anorthite (calcium feldspar), Kreip rock, etc. The mineral chemical composition is mainly silicon dioxide, titanium oxide, aluminum oxide, etc. Among them, ilmenite is distributed in the lunar sea, and the total amount of ilmenite in the whole moon is about 150 trillion.

[0004] Since there is almost no atmosphere on the moon, solar radiation can penetrate directly. Calculations show that the solar radiation energy reaching the moon every year is about 12 trillion kilowatts, which is equivalent to 25,000 times the total energy produced by various energy sources consumed on Earth in one year. Since the moon's rotation period is exactly equal to its revolution period around the earth, the moon's day and night are both 14 and a half days, and a day on the moon is equivalent to nearly a month on Earth, so the moon can obtain more solar energy.

[0005] One of the most significant obstacles to space exploration is the burden of carrying all the material resources required for a mission from Earth, which increases the launch mass required to accomplish a given mission and, in turn, increases the cost of the launch.

[0006] Therefore, it is necessary to provide an in-situ resource utilization (ISRU) system that can effectively utilize lunar resources. Summary of the invention

[0007] Based on this, it is necessary to provide an in-situ resource utilization system to address the above technical issues.

[0008] In-situ resource utilization systems include:

[0009] An excavation unit, connected to the processing unit, capable of excavating lunar soil and transporting it to the processing unit;

[0010] A processing unit, used for transporting lunar soil and molten alloy between the units of the in-situ resource utilization system;

[0011] A power generation unit, connected to the processing unit, capable of converting sunlight light energy and / or heat energy into electrical energy for providing electrical energy for the in-situ resource utilization system and heating the lunar soil to a molten state;

[0012] an electrolysis unit, connected to the power generation unit and the processing unit, capable of electrolyzing molten lunar soil to generate oxygen and molten alloy;

[0013] A gas processing unit, connected to the electrolysis unit, capable of separating, purifying, liquefying and storing the oxygen;

[0014] a metal processing unit, which is in communication with the processing unit and is capable of storing the molten alloy for further refining or processing; and a heat control unit, which performs active heat control by forced convection heat transfer through pumping fluid, collects the heat energy generated by the in-situ resource utilization system using the working fluid, and then discharges the collected heat energy by radiation heat transfer.

[0015] Optionally, the power generation unit includes a concentrator, a smelting furnace, a first thermal power generation device and a thermal energy storage device; the concentrator is connected to the smelting furnace, the first thermal power generation device and the thermal energy storage device, and can focus incident sunlight to obtain high solar flux and transmit thermal energy to the smelting furnace, the first thermal power generation device and the thermal energy storage device; the smelting furnace can heat the lunar soil transmitted thereto and heat the lunar soil to a molten state; the first thermal power generation device is connected to the concentrator and the thermal energy storage device through a heat pipe, and the working fluid heated by the concentrator is converted from thermal energy to electrical energy in the first thermal power generation device to power the in-situ resource utilization system, and the unused thermal energy is stored in the thermal energy storage device. 3. The in-situ resource utilization system according to claim 2, characterized in that the first thermal power generation device is a Stirling engine.

[0016] Optionally, the first thermal power generation device is a closed Brayton cycle.

[0017] Optionally, the electrolysis unit includes a reactor and a second thermal power generation device. After the molten lunar soil enters the reactor, it is electrolyzed to produce oxygen and molten alloy. The reactor has a gas outlet, a molten alloy outlet, a waste heat outlet and a tailings outlet. The gas outlet is connected to the gas processing unit. The molten alloy outlet is connected to the second inlet of the processing unit, and can transport the molten alloy through the second outlet of the processing unit to the metal processing unit for further processing. The waste heat outlet is connected to the second thermal power generation device, and the waste heat is recovered by the second thermal power generation device to generate electricity. The tailings outlet is connected to the third inlet of the processing unit, and the tailings are collected and processed by the processing unit.

[0018] Optionally, the second thermal power generation device is configured to provide power for the in-situ resource utilization system.

[0019] Optionally, the second thermal power generation device is configured to be used for electrolyzing the molten lunar soil.

[0020] Optionally, the gas processing unit includes a gas separator, an oxygen liquefier and an oxygen cryogenic storage tank, the outlet of the gas separator is connected to the inlet of the oxygen liquefier, the outlet of the oxygen liquefier is connected to the inlet of the oxygen cryogenic storage tank, and the oxygen discharged through the gas outlet is sequentially purified by the gas separator, liquefied by the oxygen liquefier, and then stored in the oxygen cryogenic storage tank.

[0021] Optionally, the thermal control unit includes a pump and a radiator, the pump is used to provide a working pressure greater than the vapor pressure of the working fluid to prevent the working fluid from freezing or undergoing a liquid-gas phase change in the heat pipe loop; the radiator can discharge heat energy to the lunar surface and outer space through radiation heat transfer.

[0022] The present invention has the beneficial effects of producing a large mass of metal and oxygen from the lunar regolith by using low mass return ratio and optimized process, hardware of small mass and solar energy. Compared with the conventional in-situ resource utilization system of producing metal and oxygen by electrolysis melting lunar soil, the present system directly melts the lunar soil by using high temperature heat energy generated by concentrated solar energy, reduces energy conversion links, improves heat utilization efficiency, and the process is less sensitive to raw materials, avoiding technologies that are difficult to achieve on the moon, such as particle size screening and mineral processing.

[0023] In addition, the power generation unit of the present invention includes a thermal energy storage device, which can achieve efficient power and heat supply on lunar nights, providing electricity and low-temperature protection for the lunar base.

[0024] Finally, the present invention adds a thermal power generation device to the electrolysis unit to recover the waste heat from the electrolysis of the molten weathering layer and generate electricity, thereby maximizing the use of extraterrestrial resources to support space missions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic structural diagram of an in-situ resource utilization system provided for an embodiment of the present application. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] To achieve sustainable space exploration, reliance on Earth resources must be reduced. In-situ resource utilization (ISRU), or the use of extraterrestrial resources to support space missions, can significantly reduce the launch mass and cost required for a given mission.

[0028] One avenue for exploiting space resources is to produce oxygen and metals on the lunar surface. Three of these production methods have become technically mature over the past decade: hydrogen reduction of ilmenite (HRI), carbothermal reduction of silicates (CRS), and molten regolith electrolysis (MRE). MRE is an electrochemical processing technology that directly electrolyzes molten lunar regolith to produce gaseous oxygen at the anode and liquid metal at the cathode. Because MRE can theoretically extract all of the oxygen from the lunar regolith and MRE requires neither a gas recovery system nor a water electrolyzer, considerable system mass can be saved by using MRE compared to the other two main technologies (HRI and CRS). Other advantages include the co-production of materials such as iron, silicon, aluminum, and glass that can be used to build spare parts, buildings, and solar arrays on the lunar surface. Because MRE technology is less sensitive to feedstock, the technical challenges associated with excavation of feedstock at the poles, especially from permanently shadowed craters, can be avoided through the MRE process.

[0029] First embodiment

[0030] like Figure 1 As shown, this embodiment provides an in-situ resource utilization system for producing oxygen and metals by electrolysis of molten lunar soil using concentrated solar energy, including: an excavation unit 1, a processing unit 2, a power generation unit 3, an electrolysis unit 4, a gas processing unit 5, a metal processing unit 6 and a thermal control unit 7.

[0031] The excavation unit 1 is connected to the processing unit 2 and can transport the excavated lunar soil to the processing unit 2.

[0032] The processing unit 2 is used for the transfer and transportation of the output of each related unit, and has a first inlet, a second inlet, a third inlet, a first outlet and a second outlet. The first inlet of the processing unit 2 is connected to the outlet of the excavation unit 1, the second inlet of the processing unit 2 is connected to the molten alloy outlet of the electrolysis unit 4, the third inlet of the processing unit 2 is connected to the tailings outlet of the electrolysis unit 4, the first outlet of the processing unit 2 is connected to the inlet of the power generation unit 3, and the second outlet of the processing unit 2 is connected to the inlet of the metal processing unit 6.

[0033] The power generation unit 3 is electrically connected to other units, can supply power to each unit, and is connected to the electrolysis unit 4, which includes a concentrator 31, a smelting furnace 32, a first thermal power generation device 33 and a thermal energy storage device 34; the concentrator 31 is connected to the smelting furnace 32, the first thermal power generation device 33 and the thermal energy storage device 34, and can focus the incident sunlight to obtain high solar energy flux and transmit light energy and heat energy to the smelting furnace 32, the first thermal power generation device 33 and the thermal energy storage device 34; the smelting furnace 32 can heat the lunar soil transmitted thereto and heat the lunar soil to a molten state; the first thermal power generation device 33 is connected to the concentrator 31 and the thermal energy storage device 34 through a heat pipe, and the working fluid heated by the concentrator 31 is converted from thermal energy to electrical energy in the first thermal power generation device, and the unused heat energy is stored in the thermal energy storage device 34 through the heat pipe.

[0034] In this embodiment, the power generation unit 3 can convert light energy and / or thermal energy into electrical energy to power the system, and can store unused thermal energy, thereby fully utilizing the natural resources on the lunar surface and avoiding energy waste.

[0035] The electrolysis unit 4 includes a reactor 41 and a second thermal power generation device 42. After the molten lunar soil enters the reactor 41, it is electrolyzed to produce oxygen and molten alloy. The reactor 41 has a gas outlet, a molten alloy outlet, a waste heat outlet and a tailings outlet. The gas outlet is connected to the gas processing unit 5. The molten alloy outlet is connected to the second inlet of the processing unit 2, and the molten alloy can be transported to the metal processing unit 6 through the second outlet of the processing unit 2 for further processing. The waste heat outlet is connected to the second thermal power generation device 42, and the waste heat is recovered by the thermal power generation device 42 to generate electricity. The tailings outlet is connected to the third inlet of the processing unit 2, and the tailings are collected and processed by the processing unit 2.

[0036] In this embodiment, the second thermal power generation device 42 can be used to power the in-situ resource utilization system, and can also be used to electrolyze molten lunar soil, thereby making full use of energy.

[0037] The gas processing unit 5 includes a gas separator 51, an oxygen liquefier 52 and an oxygen cryogenic storage tank 53. The outlet of the gas separator 51 is connected to the inlet of the oxygen liquefier 52, and the outlet of the oxygen liquefier 52 is connected to the inlet of the oxygen cryogenic storage tank 53. The oxygen discharged through the gas outlet is purified by the gas separator 51 and liquefied by the oxygen liquefier 52 to become pure liquid oxygen, and finally stored in the oxygen cryogenic storage tank 53.

[0038] In this embodiment, the gas separator 51 applies an active voltage to the electrodes. At the cathode, the oxygen in the gas flow is ionized and reduced to oxygen anions, and then the electric field is transmitted between the electrodes through the electrolyte. At the anode, the oxygen anions are oxidized to oxygen gas, thereby achieving separation of oxygen from other volatile components.

[0039] In this embodiment, the thermal control unit 7 uses an active thermal control (ATC) device that mechanically pumps fluid to force convection heat exchange, which is connected to other units through heat pipes and working fluids. Specifically, the thermal control unit 7 includes a pump 71 and a radiator 72. The pump 71 is used to provide a working pressure greater than the vapor pressure of the working fluid to prevent the working fluid from freezing in the heat pipe loop or undergoing a liquid-gas phase change; the radiator 72 can discharge heat energy to the lunar surface and outer space through radiation heat transfer. Since space is a low-temperature environment, the heat dissipation efficiency of the thermal control unit 7 provided by this embodiment is relatively high.

[0040] The operating principle of the in-situ resource utilization system provided in this embodiment is explained below: the excavation unit 1 excavates and loads the lunar soil of the lunar regolith under the low gravity conditions on the moon (therefore, in some contents of this embodiment, the "regolith" will also be used to refer to the lunar soil of the regolith), and transports it to the processing unit 2 through the first entrance of the processing unit 2.

[0041] The lunar soil transported to the processing unit 2 enters the power generation unit 3 from the first outlet of the processing unit 2, and is heated into a molten state therein before being transported to the electrolysis unit 4.

[0042] During the daytime on the moon, sunlight is focused and converted into thermal energy through a concentrator 31 with high concentration that can track the position of the sun in real time. Part of the thermal energy is used by the smelting furnace 32 to heat the molten lunar soil, and another part of the thermal energy is transferred to the first thermal power generation device 33 of the power generation unit 3 through the working fluid in the heat pipe (also referred to as the working fluid in this application) and converted into electrical energy. The remaining thermal energy is transferred to the thermal energy storage device 34 through the working fluid in the heat pipe; during the nighttime on the moon, part of the thermal energy in the thermal energy storage device 34 is transferred to the thermal power generation device 33 through the working fluid in the heat pipe for power supply, and the remaining thermal energy is used to heat the in-situ resource utilization system, and the electrical energy is transported to each unit from the power outlet of the first thermal power generation device 33.

[0043] In this embodiment, the power generation unit 3 is used as the power source, wherein the first thermal power generation device 33 is a Stirling engine. During the daytime of the moon, the concentrator 31 concentrates solar energy into the receiver heat pipe and the smelting furnace 32, and serves as a high-temperature heat source to heat the working fluid in the heat pipe and the lunar soil in the smelting furnace 32. The time of the moon's day and night is about 350 hours. Since the moon has no atmospheric environment, the temperature of the moon during the day can reach 400K, which is much higher than the temperature of the earth, thus effectively reducing the heat loss of the receiver of the concentrator 31. The heated working fluid converts heat energy into electrical energy through the thermal power generation device 33 (i.e., the Stirling engine), and the heated lunar soil becomes molten and is transported to the reactor 41 for further electrolysis, while the remaining heat energy is transported to the thermal energy storage device 34 through the working fluid in the heat pipe. The temperature of the thermal energy storage device 34 will gradually increase over time until the end of the lunar day. During the lunar night, all the energy required by the lunar base comes from the heat energy stored in the thermal energy storage device 34, and part of the energy can directly provide heat energy to the lunar base to provide low-temperature protection for instruments and equipment. Another part of the energy is converted into electrical energy through the Stirling engine 33. The space cold source enables the Stirling cycle to maintain high efficiency even under low-temperature heat input during the lunar night. Therefore, the power generation unit 3 can continuously and efficiently supply electricity during the lunar day and night. During the lunar night, as the heat energy is utilized, the temperature of the thermal energy storage device 34 gradually decreases. The system adjusts the heating supply of the lunar base so that the thermal energy storage device 34 returns to its original temperature at the end of the lunar night, preparing for the subsequent heat storage during the lunar day.

[0044] In this embodiment, reactor 41 is specifically a molten regolith electrolysis (MRE) reactor, and the molten regolith is directly electrolyzed in reactor 41 to produce metal and oxygen. In the MRE process, the molten regolith (molten lunar soil) is fed into an electrolytic cell, and a potential is applied between two electrodes immersed in the molten regolith. The conductivity of the molten regolith is high enough to drive the current and maintain the electrolysis of the oxide. The oxygen anions move toward the inert anode and are oxidized to gaseous oxygen at the anode. The metal cations are reduced at the cathode to form liquid metal. Reactor 41 uses molten regolith electrolysis technology to reduce most of the components present in the lunar regolith, and this process is less sensitive to the composition of the mineral regolith. And in reactor 41, only metal accumulates at the cathode for easy extraction. The composition of the alloy produced at the cathode of reactor 41 can be controlled by adjusting the operating temperature and the applied potential.

[0045] In this embodiment, the reactor 41 uses the heat generated by the current passing through the resistance melt to maintain the molten weathered layer core, and the molten area is surrounded by the solid weathered layer, the central molten core is surrounded by the phase boundary, where the solid / liquid phase transition occurs, and the thermal gradient is designed so that the molten core is insulated by the solid weathered layer around the reactor. These solid weathered layers isolate and protect the side walls of the reactor 41 from corrosion, and the solid weathered layer in contact with the side walls of the reactor 41 is not corrosive, so that the long-term operation of the reactor 41 can be maintained.

[0046] Second embodiment

[0047] The in-situ resource utilization system provided by the second embodiment is different from the first embodiment in that a closed Brayton cycle is used in the power generation unit 3 to replace the Stirling engine for power generation. During the lunar day, part of the solar energy focused by the concentrator 31 is received by the heat pipe, which is used as a high-temperature heat source to heat the working fluid in the heat pipe. The heated working fluid transfers part of the heat energy to the heat source of the closed Brayton cycle 33 through the heat pipe and then converts it into electrical energy. During the lunar night, part of the heat energy stored in the thermal energy storage device 34 is transferred to the heat source of the closed Brayton cycle 33 through the heat pipe to generate electricity for use in the lunar base.

[0048] In this embodiment, the Brayton cycle realizes efficient energy conversion through four processes: adiabatic compression, isobaric heat absorption, adiabatic expansion and isobaric heat release. Taking the closed Brayton cycle 33 as a supercritical carbon dioxide Brayton cycle as an example, the working process based on the closed Brayton cycle 33 is as follows: the low-temperature and low-pressure supercritical carbon dioxide working fluid is pressurized by the compressor, and heat is exchanged with the exhaust gas discharged from the gas turbine through the regenerator. After being preheated to a certain temperature, it is further heated by the heat source, and then enters the turbine to expand and do work to drive the generator to generate electricity. The exhaust gas that has done work enters the regenerator to exchange heat with the low-temperature and high-pressure working fluid discharged from the compressor for precooling. The precooled working fluid enters the cooler for further cooling, and finally enters the compressor for compression to complete the entire cycle. The supercritical carbon dioxide fluid with a temperature and pressure above the critical value is used as a working fluid for the thermodynamic cycle, and has the characteristics of high heat transfer efficiency, strong work capacity, low viscosity, strong fluidity, high density, good compressibility, low corrosiveness, and high chemical stability. And when the working fluid carbon dioxide is in a supercritical state, the change of the working fluid phase is avoided, the consumption of compression work is reduced, and the cycle efficiency is greatly improved. Due to the unique properties of the closed Brayton cycle 33, the thermal cycle using the closed Brayton cycle 33 for power generation has the following advantages: high cycle efficiency of the device, low cycle temperature, small cycle loss, compact system structure, small size, low electricity, construction and operation and maintenance costs, long life, and good economic benefits.

[0049] So far, the technical solution of the present invention has been described in conjunction with the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to the above-mentioned specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. An in-situ resource utilization system, characterized in that: include: An excavation unit, connected to the processing unit, capable of excavating lunar soil and transporting it to the processing unit; A processing unit, used for transporting lunar soil and molten alloy between the units of the in-situ resource utilization system; A power generation unit, connected to the processing unit, capable of converting sunlight light energy and / or heat energy into electrical energy for providing electrical energy for the in-situ resource utilization system and heating the lunar soil to a molten state; an electrolysis unit, connected to the power generation unit and the processing unit, capable of electrolyzing molten lunar soil to generate oxygen and molten alloy; A gas processing unit, connected to the electrolysis unit, capable of separating, purifying, liquefying and storing the oxygen; a metal processing unit, connected to the processing unit, capable of storing the molten alloy for further refining or processing; as well as The heat control unit performs active heat control by pumping fluid to force convection heat transfer, collects the heat energy generated by the in-situ resource utilization system using the working fluid, and then discharges the collected heat energy by radiation heat transfer.

2. The in-situ resource utilization system according to claim 1, characterized in that: The power generation unit includes a concentrator, a smelting furnace, a first thermal power generation device and a thermal energy storage device; the concentrator is connected to the smelting furnace, the first thermal power generation device and the thermal energy storage device, and can focus incident sunlight to obtain high solar energy flux and transmit thermal energy to the smelting furnace, the first thermal power generation device and the thermal energy storage device; the smelting furnace can heat the lunar soil transmitted thereto and heat the lunar soil to a molten state; the first thermal power generation device is connected to the concentrator and the thermal energy storage device through a heat pipe, and the working fluid heated by the concentrator is converted from thermal energy to electrical energy in the first thermal power generation device to power the in-situ resource utilization system, and the unused thermal energy is stored in the thermal energy storage device.

3. The in-situ resource utilization system according to claim 2, characterized in that: The first thermal power generation device is a Stirling engine.

4. The in-situ resource utilization system according to claim 2, characterized in that: The first thermal power generation device is a closed Brayton cycle.

5. The in-situ resource utilization system according to any one of claims 1 to 4, characterized in that: The electrolysis unit includes a reactor and a second thermal power generation device. After the molten lunar soil enters the reactor, it is electrolyzed to produce oxygen and molten alloy. The reactor has a gas outlet, a molten alloy outlet, a waste heat outlet and a tailings outlet. The gas outlet is connected to the gas processing unit. The molten alloy outlet is connected to the second inlet of the processing unit, and can transport the molten alloy through the second outlet of the processing unit to the metal processing unit for further processing. The waste heat outlet is connected to the second thermal power generation device, and the waste heat is recovered by the second thermal power generation device to generate electricity. The tailings outlet is connected to the third inlet of the processing unit, and the tailings are collected and processed by the processing unit.

6. The in-situ resource utilization system according to claim 5, characterized in that: The second thermal power generation device is configured to supply power to the in-situ resource utilization system.

7. The in-situ resource utilization system according to claim 5, characterized in that: The second thermal power generation device is configured to be used for electrolyzing the molten lunar soil.

8. The in-situ resource utilization system according to any one of claims 1 to 4, characterized in that: The gas processing unit includes a gas separator, an oxygen liquefier and an oxygen cryogenic storage tank. The outlet of the gas separator is connected to the inlet of the oxygen liquefier, and the outlet of the oxygen liquefier is connected to the inlet of the oxygen cryogenic storage tank. The oxygen discharged through the gas outlet is purified by the gas separator, liquefied by the oxygen liquefier, and then stored in the oxygen cryogenic storage tank.

9. The in-situ resource utilization system according to any one of claims 1 to 4, characterized in that: The thermal control unit includes a pump and a radiator. The pump is used to provide a working pressure greater than the vapor pressure of the working fluid to prevent the working fluid from freezing or undergoing a liquid-gas phase change in the heat pipe loop; the radiator can discharge heat energy to the lunar surface and outer space through radiation heat transfer.

10. The in-situ resource utilization system according to claim 5, characterized in that: The reactor is a molten weathering layer electrolysis reactor.

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