SYSTEMS AND METHODS FOR IN-SITU RESOURCE PROCESSING AND IN-SITU RESOURCE UTILISATION

Description

TECHNICAL FIELD

The following relates generally to space resources and, more particularly, to systems and methods for In-Situ Resource Processing and In-Situ Resource Utilisation.

INTRODUCTION

With increasing interest in space exploration from private industry, government, and academia, there has been greater efforts to develop novel space technology. Many see the Moon as the primary location for attaining near-term goals in space development, which could then be continually developed for further exploration beyond the Moon. In order to successfully allow humans to inhabit and research the Moon, a lunar infrastructure must be developed to sustain life on its surface.

Two of the most critical areas of lunar research are In-Situ Resource Processing (ISRP) and In-Situ Resource Utilisation (ISRU). Lunar ISRP and ISRU are the respective methods of processing and using resources naturally found on the Moon's surface for desired applications. The ISRP and ISRU processes follow material acquisition, which includes mining, excavation, and transporting the material to a processing plant.

ISRP and ISRU methods typically involve the processing and use of lunar regolith, the outermost lunar surface. This layer typically ranges from depths of 5-15 meters depending on the region with particle sizes ranging from tens of microns to large rocks, with majority of grains ranging from 40-100 microns. Lunar regolith is a blanket of unconsolidated rock covering the lunar surface as a result of meteoroid impacts and impacts from charged particles from the sun and other stars. The composition of lunar regolith is a mixture of metal oxide particles and consists of many useful components, such as oxygen, iron, aluminum, silicon, and may be a useful material in itself as a whole for certain applications. Based on the soil composition, lunar regolith is approximately 45% oxygen by weight.

One major challenge with ISRP and ISRU methods is that they require immense amounts of power. The power requirement is largely due to the heat required to physically alter the regolith for many of the processes. For reference, the energy required to melt 1 kg of regolith can be approximately 1.5 MJ. Additional power may then be needed to maintain a set temperature of regolith and to conduct a select process on the material.

Regardless of the method of processing lunar regolith, typically some initial physical processing is required in all cases to increase the efficiency and yield of desired species. This is typically a reduction in particle size through milling or other methods, followed by particle filtering to only use particles of a desired size. Such processes may target different elements in the lunar material to extract depending on the desired use case for the material. All of the processes are generally energy intense and require large power generation. A summary and review of some existing commonly researched and developed ISRP methods follows.

In carbo-thermal methods, lunar regolith is chemically reduced using carbon compounds, typically methane. The methane and regolith reduction reaction produces hydrogen and carbon monoxide. These products can then be converted into methane and water using a Sabatier reaction. The water is then electrolysed into hydrogen and oxygen gas. Finally, the methane can be returned and reused in the reduction reaction. This multi-step process requires the regolith to be molten and reach temperatures above 1600° C. and produces oxygen at a theoretical 50% yield. A distinct advantage of this method is the recyclability of the methane. The disadvantages of carbo-thermal methods are the high operating temperature and the possible loss of product due to the multi-step nature and inefficiencies of the method. There have been theoretical designs of an ISRU system, weighing 940 kg, that can extract 1000 kg of oxygen per year which can be combined with free solar hydrogen to create stable and storable water. A small scale carbothermal reactor has been build and tested demonstrating some capabilities of this method.

With molten regolith electrolysis (MRE), a standard electrolytic cell with an anode and cathode is required. When a sufficient potential is applied, the molten regolith decomposes into oxygen at the anode and metal at the cathode. The advantage of this system is that untreated regolith is the only material input used for the system and supplemental material from Earth is not required. The large drawbacks of this process are the high operating temperature of 1600° C. to melt the regolith and the costly components for the anode. Only expensive platinum-group metals have been proven to succeed with this method and must be changed frequently. MRE reactors have been tested with an operating temperature of 1600° C. This can result in an efficiency of about 94% when extracting 35 g of oxygen per 100 g of regolith.

The FFC Cambridge Method is a well-documented process of reducing mineral oxides into 99%-pure metal. The standard FCC process uses an electrolytic cell kept at approximately 900° C. with a metal oxide as the cathode, a carbon-based compound as the anode, and molten calcium chloride as the electrolyte. When a potential is applied across the cell, the oxide ions transfer to the anode and are released as carbon oxides (CO and CO₂). When using this method on lunar regolith, the target is to release oxygen molecules. In this configuration, two known anode compounds are capable of releasing oxygen gas: (1) doped tin oxide (SnO₂), and (2) a solid solution of calcium titanate and calcium ruthenate. Experimental tests have shown that the lifetime of the tin oxide is limited to a few hours due to erosion observed at the anode as well as a thin layer of calcium stannate, an insulator, coating the anode and hindering the electrochemical process. The calcium mixture has been shown to release oxygen gas for over 100 hours, making anodes of the composition CaTixRu1-xO3 more desirable. An experiment using the FFC Cambridge process was run with an ilmenite (FeTiO₃, present in lunar basalts) cathode, which was able to produce oxygen for 9 hours. In the context of ISRU, the inability to replenish the electrolyte as it is consumed throughout the reaction presents a disadvantage.

In vapor phase pyrolysis (VPP), when placed in a vacuum at sufficiently high temperatures, lunar regolith will evaporate. This temperature will need to be greater than 2000° C., therefore requiring a large amount of energy. In its gaseous form, the metal oxides that make up most of the regolith decompose into suboxides, metal, and oxygen. This oxygen and metal can then be siphoned and cooled to be used for life support, technology, and fuel. Oxygen can be combined with free solar hydrogen to create storable water. Although VPP also requires high operating temperatures, the main attraction of this method is that it uses in-situ resources available on the Moon without requiring additives. The oxygen yields of this process are 50%. However, it is important to note that the oxygen and metals need to be cooled immediately in order to prevent the metals from recombining with the oxygen.

Water electrolysis is the process of taking the water and separating it into hydrogen and oxygen. The difficulty with this method on the lunar surface is retrieving the water and refining it to a state that could be easily processed. The water content on the sunlit side of the Moon is 100-412 ppm (0.01%-0.042%), and there is evidence that there are much higher volumes in the permanently shadowed regions near the poles. One benefit of this method is that liquid hydrogen/oxygen rockets could deposit any excess fuel into the processing plant to produce hydrogen and oxygen. However, to use this processing method effectively with in-situ resources, much energy would need to be spent transporting and heating the water. Due to the lack of technology readiness and lack of abundant water everywhere on the lunar surface this method is not readily available.

Accordingly, there is a need for an improved system and method for lunar In-Situ Resource Processing and In-Situ Resource Utilisation that overcomes at least some of the disadvantages of existing systems and methods.

This background information is provided to reveal information believed by the applicant to be of possible relevance to the present disclosure. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present disclosure.

SUMMARY

A system for in-situ resource processing is provided. The system includes an electrolytic cell configured to contain molten regolith. The system further includes an anode and a cathode configured to be provided at the molten regolith. The system further includes a variable electrical source configured to apply a stepped voltage across the anode and the cathode to obtain decomposition of a first metal oxide, and vary the stepped voltage to obtain decomposition of a second metal oxide.

In an embodiment, the molten regolith is molten lunar regolith.

In an embodiment, the first metal oxide and second metal oxide each include a different one of potassium oxide (K2O), iron (III) oxide (Fe₂O₃), iron (II) oxide (FeO), sodium oxide (Na₂O), chromium (III) oxide (Cr2O3), manganese (II) oxide (MnO), silicon dioxide (SiO₂), titanium dioxide (TiO2), aluminium (III) oxide (Al2O3), magnesium oxide (MgO), and calcium oxide (CaO).

In an embodiment, the electrolytic cell is powered at least in part by space-based solar power.

In an embodiment, the electrical source is powered at least in part by space-based solar power.

In an embodiment, the anode includes one of doped tin oxide (SnO2), and a solid solution of calcium titanate and calcium ruthenate.

A method of in-situ resource processing is provided. The method includes providing molten regolith in an electrolytic cell. The method further includes providing an anode and a cathode at the molten regolith. The method further includes applying a stepped voltage across the anode and the cathode to obtain decomposition of a first metal oxide. The method further includes varying the stepped voltage to obtain decomposition of a second metal oxide.

In an embodiment, the molten regolith is molten lunar regolith.

In an embodiment, the first metal oxide and second metal oxide each include a different one of potassium oxide (K2O), iron (III) oxide (Fe2O3), iron (II) oxide (FeO), sodium oxide (Na2O), chromium (III) oxide (Cr2O3), manganese (II) oxide (MnO), silicon dioxide (SiO2), titanium dioxide (TiO2), aluminium (III) oxide (Al2O3), magnesium oxide (MgO), and calcium oxide (CaO).

In an embodiment, the electrolytic cell is powered at least in part by space-based solar power.

In an embodiment, an electrical source providing the stepped voltage is powered at least in part by space-based solar power.

In an embodiment, the anode includes one of doped tin oxide (SnO₂), and a solid solution of calcium titanate and calcium ruthenate.

A system for in-situ resource processing is provided. The system includes a vacuum chamber configured to contain regolith. The system further includes a variable temperature control configured to apply a stepped temperature to the vacuum chamber to obtain decomposition of a first metal oxide, and vary the stepped temperature to obtain decomposition of a second metal oxide.

In an embodiment, the regolith is lunar regolith.

In an embodiment, the first metal oxide and second metal oxide each include a different one of potassium oxide (K2O), iron (III) oxide (Fe2O3), iron (II) oxide (FeO), sodium oxide (Na2O), chromium (III) oxide (Cr2O3), manganese (II) oxide (MnO), silicon dioxide (SiO2), titanium dioxide (TiO2), aluminium (III) oxide (Al2O3), magnesium oxide (MgO), and calcium oxide (CaO).

In an embodiment, the vacuum chamber is powered at least in part by space-based solar power.

In an embodiment, the variable temperature control is powered at least in part by space-based solar power.

In an embodiment, the system further includes a siphoning apparatus configured to siphon decomposed oxygen and metal from the vacuum chamber.

A method of in-situ resource processing is provided. The method includes providing regolith in a vacuum chamber. The method further includes applying a stepped temperature to the vacuum chamber to obtain decomposition of a first metal oxide. The method further includes varying the stepped temperature to obtain decomposition of a second metal oxide.

In an embodiment, the regolith is lunar regolith.

In an embodiment, the first metal oxide and second metal oxide each include a different one of potassium oxide (K2O), iron (III) oxide (Fe2O3), iron (II) oxide (FeO), sodium oxide (Na2O), chromium (III) oxide (Cr2O3), manganese (II) oxide (MnO), silicon dioxide (SiO2), titanium dioxide (TiO2), aluminium (III) oxide (Al2O3), magnesium oxide (MgO), and calcium oxide (CaO).

In an embodiment, the vacuum chamber is powered at least in part by space-based solar power.

In an embodiment, a variable temperature control controlling the stepped temperature is powered at least in part by space-based solar power.

In an embodiment, the system further includes a siphoning apparatus configured to siphon decomposed oxygen and metal from the vacuum chamber.

Other aspects and features will become apparent, to those ordinarily skilled in the art, upon review of the following description of some exemplary embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings included herewith are for illustrating various examples of articles, methods, and apparatuses of the present specification. In the drawings:

FIG. 1 is a block diagram of an example system for in-situ resource processing, according to an embodiment;

FIG. 2 is a is a flowchart of an example method of in-situ resource processing, according to an embodiment;

FIG. 3 is a block diagram of another example system for in-situ resource processing, according to an embodiment; and

FIG. 4 is a is a flowchart of another example method of in-situ resource processing, according to an embodiment.

DETAILED DESCRIPTION

Various apparatuses or processes will be described below to provide an example of each claimed embodiment. No embodiment described below limits any claimed embodiment and any claimed embodiment may cover processes or apparatuses that differ from those described below. The claimed embodiments are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below.

As used herein, the term “about” should be read as including variation from the nominal value, for example, a +/−10% variation from the nominal value. It is to be understood that such a variation is always included in a given value provided herein, whether or not it is specifically referred to.

One or more systems described herein may be implemented in computer programs executing on programmable computers, each comprising at least one processor, a data storage system (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. For example, and without limitation, the programmable computer may be a programmable logic unit, a mainframe computer, server, and personal computer, cloud-based program or system, laptop, personal data assistance, cellular telephone, smartphone, or tablet device.

Each program is preferably implemented in a high-level procedural or object-oriented programming and/or scripting language to communicate with a computer system. However, the programs can be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language. Each such computer program is preferably stored on a storage media or a device readable by a general or special purpose programmable computer for configuring and operating the computer when the storage media or device is read by the computer to perform the procedures described herein.

A description of an embodiment with several components in communication with each other does not imply that all such components are required. On the contrary, a variety of optional components are described to illustrate the wide variety of possible embodiments of the present disclosure.

Further, although process steps, method steps, algorithms or the like may be described (in the disclosure and/or in the claims) in a sequential order, such processes, methods and algorithms may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of processes described herein may be performed in any order that is practical. Further, some steps may be performed simultaneously.

When a single device or article is described herein, it will be readily apparent that more than one device/article (whether or not they cooperate) may be used in place of a single device/article. Similarly, where more than one device or article is described herein (whether or not they cooperate), it will be readily apparent that a single device/article may be used in place of the more than one device or article.

The following relates generally to lunar natural resources, and more particularly to systems and methods for lunar In-Situ Resource Processing (ISRP) and In-Situ Resource Utilisation (ISRU).

To address the various limitations and challenges present in existing methods, embodiments disclosed herein describe techniques for ISRP. Molten regolith may be provided in an electrolytic cell. An anode and a cathode may also be provided at the molten regolith. By applying a stepped voltage across the anode and the cathode, decomposition of a first metal oxide may be obtained. Then, by varying the stepped voltage to decomposition of a second metal oxide may be obtained. Overall, each product of lunar regolith processing could serve a purpose in the construction of lunar infrastructure.

Space-Based Solar Power (SBSP) presents itself as a desirable solution to the power requirement for ISRP and ISRU methods. Solar energy is an abundant source of power in space and up to 1367 W/m2 is received by the Moon. This is also a source of power that will nearly always be available as shadowing of the solar arrays will be limited. SBSP consists of using large solar arrays to harness large amounts of electrical energy, which can then be transferred to a receiver near the power usage site via a laser or microwaves, and converted back into useable electrical energy.

There have been several concepts proposed for SBSP designs such as the reference system as defined by DOE/NASA, and SunTower, SolarDisc, Integrated Symmetrical Concentrator by NASA, Sun Sail by ESA, Tethered-SSPS by Japan, the Sandwich Type Solar Power Satellite concept as proposed by Kobe University and many others. All of these concepts are on a very large scale with areas of several square kilometers, weighing hundreds or thousands of metric tonnes, and with proposed power production on the order of hundreds of megawatts, or even gigawatts. These systems also typically consist of modular designs such that they could be constructed in pieces in orbit, and large rectennas that occupy several square kilometers on the surface of where the power will be used.

Wireless Power Transmission (WPT) technologies such as microwaves or lasers have been in ideation and development for several years and will be critical for transferring this power over long distances through space. Research groups have focused on SBSP and WPT for space-based and earth-based applications. For example, researchers have demonstrated the ability to wirelessly transmit microwave power from a satellite in space to the Earth's surface. At this point in time, both microwave and laser power transmission have relatively low efficiency, require a large footprint, and are subject to environmental factors. Such technologies, while still in development, have demonstrated progress and promising results.

In time, SBSP technologies may be developed to a technological readiness level that allow for large-scale transfer of energy from orbital space to the surface of an inhabited body.

One notable feature of SBSP is the scalability of the systems for power collection. In space, massive structures could be created in zero gravity to generate large amounts of power. The scalability of SBSP would allow sufficient power to be transmitted to the lunar surface for the energy intensive ISRP and ISRU methods.

It is of note that nuclear power sources could also produce sufficient power for ISRP and ISRU methods in a very efficient manner. However, with more private corporations having access to space, but not having access to restricted materials, alternative power sources are required. Similar to how nuclear power could be utilised more on Earth, it is limited due to reasons beyond the design and capabilities of the power source. Overall, SBSP is a promising candidate to supply large amounts of energy to the lunar surface for ISRP and ISRU methods.

The fields of ISRP and ISRU are currently largely centered on the efficiencies and yields of the processes. For material processing methods, it is desirable to produce as much product with as little input material as possible. This will ensure that material is not wasted and requires less energy to produce. For utilisation, it is desirable to develop technology at full-scale to validate performance and to demonstrate the integration of ISRU components in space missions.

As these methods become efficient enough and reach a sufficient technological readiness level (TRL) they can be used at scale to build key components of lunar infrastructure. Disclosed herein are high energy ISRP and ISRU methods that may be enabled by SBSP, which present a novel method of material processing, and demonstrate the importance of ISRP and ISRU methods for the construction and maintenance of SBSP as well as other lunar infrastructure that will be critical for human inhabitation.

Advantageously, using in-situ materials will reduce the amount of material required to be brought from Earth to the Moon during missions, thereby reducing the cost of lunar missions and allowing cargo space for other resources during launch. Launch costs will therefore also be reduced.

Overall, processes disclosed herein will be fundamental building blocks for humans exploring and inhabiting the lunar surface and may provide the potential to greatly accelerate lunar infrastructure development.

Moreover, combining techniques disclosed herein with existing ISRP methods shows the potential to produce large amounts of individual elements such as oxygen, aluminum, iron and silicon. Similarly, the potential to produce useful metal allows or silicon-based glass products is also evident.

Referring now to FIG. 1, shown therein is a cross-section of a system 100 for in-situ resource processing, according to an embodiment.

The system 100 includes an electrolytic cell 102 configured to contain molten regolith 108.

The system 100 further includes an anode 115 and a cathode 105 configured to be provided at the molten regolith 108.

A surface 116 of the molten regolith 108 is also depicted for reference.

While the anode 115 and the cathode 105 are depicted as being partially submerged in the molten regolith 108 according to one embodiment of the present disclosure, it will be reasonably understood that the anode 115 and cathode 105 may be provided in other suitable ways. For example, cathode 105 may be a liquid cathode provided at the bottom of the electrolytic cell 102.

The system 100 further includes a variable electrical source 110.

The electrical source 110 is configured to apply a stepped voltage across the anode 115 and the cathode 105 to obtain decomposition of a first metal oxide 112.

A plurality of the first metal oxide 112 are depicted as being present in the molten regolith 108.

The electrical source 110 is further configured to vary the stepped voltage to obtain decomposition of a second metal oxide 114.

In some embodiments, the electrical source 110 is further configured to vary the voltage applied equal to the decomposition potential of the lowest decomposition metal oxide. The voltage is then subsequently increased in steps to the following metal oxide potential.

A plurality of the second metal oxide 114 are depicted as being present in the molten regolith 108.

It will be understood that these depictions of the first metal oxide 112 and the second metal oxide 114 are only examples and are not limiting. As such, there may be any number of different metal oxides present in the molten regolith 108.

The system 100 further depicts oxygen 106 at the anode 115, and a metal 104 at the cathode 105. It will be reasonably understood that this depiction indicates the decomposition of a metal oxide (e.g., first metal oxide 112) into an oxygen 106 component and a metal 104 component.

The system 100 provides a novel material processing technique based on an improved molten regolith electrolysis (MRE) system, according to an embodiment, that will allow for a more refined processing of regolith. This in turn may provide more benefits for certain applications.

When a sufficient voltage and current are applied to the solution of molten regolith, the metals and metal oxides will separate and may be extracted from the solution. Building on this, the decomposition of each individual metal oxide occurs at a different voltage.

The below table lists examples of the oxidative decomposition potentials of lunar metal oxides at 1300K implemented by the system 100 in an embodiment:

			JSC-1	Lunar Soil
	Oxide	—E°(V)	Conc. (wt %)	Conc. (wt %)

	K2O	0.748	0.82	0.6
	Fe2O3	0.842	3.44	0
	FeO	0.986	7.35	10.5
	Na2O	1.117	2.7	0.7
	Cr2O3	1.363	0.04	0.2
	MnO	1.486	0.18	0.1
	SiO2	1.757	47.7	47.3
	TiO2	1.822	1.59	1.6
	Al2O3	2.179	15.02	17.8
	MgO	2.376	0.18	0.1
	CaO	2.59	0.04	0.2

Using a stepped voltage method the species dissociation and removal will happen subsequently for each metal oxide pair, starting with potassium oxide and ending with calcium oxide.

Alternatively, select groups of metal oxide pairs may be extracted subsequently. For example, if 1V is applied to the solution, iron and a small amount of potassium could be extracted from the regolith.

Overall, this will decrease the amount of post processing required as higher purity products may be extracted compared to a standard MRE method. This would then reduce the cost of processing the residual materials and could provide purer metal material for certain applications after dissociation.

However, one requirement of this technique is the need to maintain the regolith at elevated temperatures for a longer period of time as the material is processed. This would need to be weighed against the desire of obtaining a purer (or more specific) end product.

In various embodiments, the molten regolith 108 is molten lunar regolith.

In some embodiments, the molten regolith 108 is molten martian regolith.

In some embodiments, the molten regolith 108 is molten regolith made from materials harvested from asteroid sources, planetoids, other celestial bodies or a combination thereof.

In some embodiments, the molten regolith 108, is molten regolith made from materials from recycling space debris, satellites in orbit, or other materials transported from Earth to space.

In some embodiments, the first metal oxide and second metal oxide each include a different one of potassium oxide (K₂O), iron (III) oxide (Fe₂O₃), iron (II) oxide (FeO), sodium oxide (Na₂O), chromium (III) oxide (Cr₂O₃), manganese (II) oxide (MnO), silicon dioxide (SiO₂), titanium dioxide (TiO₂), aluminium (III) oxide (Al₂O₃), magnesium oxide (MgO), and calcium oxide (CaO).

In some embodiments, the electrolytic cell 102 is powered at least in part by space-based solar power.

In some embodiments, the electrical source 110 is powered at least in part by space-based solar power.

While different in-situ resource processing techniques may vary, they typically all require large amounts of power. As disclosed herein, such power may be at least partially supported and/or supplied by space-based solar power (SBSP).

In some embodiments, the anode 115 includes one of doped tin oxide (SnO₂), and a solid solution of calcium titanate and calcium ruthenate.

In various embodiments, the cathode 105 includes a metal oxide.

It is of note that by using particular compounds for the cathode and anode, the novel ISRP technique disclosed herein using a variable stepped voltage may be applied to the FFC Cambridge process. Therefore, improved techniques disclosed herein may not be limited to only the existing MRE process.

Referring now to FIG. 2, shown therein is a method 200 of in-situ resource processing. In an embodiment, the method 200 is implemented in the system 100 of FIG. 1.

At 210, the method 200 includes providing molten regolith in an electrolytic cell.

At 220, the method 200 further includes providing an anode and a cathode at the molten regolith.

At 230, the method 200 further includes applying a stepped voltage across the anode and the cathode to obtain decomposition of a first metal oxide.

At 240, the method 200 further includes varying the stepped voltage to obtain decomposition of a second metal oxide.

The processing methods described herein could also be used to recycle and reuse old equipment and material made from lunar resources. As these methods will be able to process lunar regolith, they will similarly be able to process parts made from lunar regolith.

Pre-processing may likely be required to break down old components into a regolith like consistency in this case. This recyclable property will reduce the amount of material required from Earth. Overall, there are several uses for the materials processed from lunar regolith that will help to accelerate the growth and development of a lunar infrastructure.

In various embodiments, the molten regolith is molten lunar regolith.

In some embodiments, the first metal oxide and second metal oxide each include a different one of potassium oxide (K₂O), iron (III) oxide (Fe₂O₃), iron (II) oxide (FeO), sodium oxide (Na₂O), chromium (III) oxide (Cr₂O₃), manganese (II) oxide (MnO), silicon dioxide (SiO₂), titanium dioxide (TiO₂), aluminium (III) oxide (Al₂O₃), magnesium oxide (MgO), and calcium oxide (CaO).

In some embodiments, the electrolytic cell is powered at least in part by space-based solar power.

In some embodiments, an electrical source providing the stepped voltage is powered at least in part by space-based solar power.

While different in-situ resource processing techniques may vary, they typically all require large amounts of power. As disclosed herein, such power may be at least partially supported and/or supplied by space-based solar power (SBSP).

In some embodiments, in-situ resource processing techniques may also be supported by other power generation sources such as nuclear fusion and/or fission reactors, thermal power plants, thermophotovoltaics, Stirling engines, thermoelectric generators, regenerative fuel cells, and/or electrostatic tether power generation or the like.

In various embodiments, SBSP may be used to generate the large amount of energy required to keep the products hot to be casted into a desirable form. If high-purity iron and aluminum can be gathered from the regolith the properties of the metal materials can be tailored towards whatever application they are trying to fulfill.

Another application of high purity metals is the use of aluminum in solid rocket fuel. Aluminum is a common additive in solid rocket fuel due to its high energy production. Metals and metallic alloys could also be used in metal additive manufacturing to produce more complex parts that would otherwise need to be machined on Earth and transported to the lunar surface. This could be critical for repairing and maintaining systems that would otherwise need replacement parts shipped from earth.

In some embodiments, the anode includes one of doped tin oxide (SnO₂), and a solid solution of calcium titanate and calcium ruthenate.

In various embodiments, the cathode includes a metal oxide.

It is of note that by using particular compounds for the cathode and anode, the novel ISRP technique disclosed herein using a variable stepped voltage may be applied to the FFC Cambridge process. Therefore, improved techniques disclosed herein may not be limited to only the existing MRE process.

Referring now to FIG. 3, shown therein is a cross-section of a system 300 for in-situ resource processing, according to an embodiment.

The system 300 includes a vacuum chamber 302 configured to contain regolith 208.

A plurality of a first metal oxide 312 and a plurality of a second metal oxide 314 are depicted as being present in the regolith 308. It will be understood that these depictions are only examples and are not limiting. As such, there may be any number of different metal oxides present in the regolith 308.

The system 100 further includes a variable temperature control 310.

When placed in the vacuum chamber 302 at sufficiently high temperatures, the regolith 308 will evaporate.

The variable temperature control 310 is configured to apply a stepped temperature to the vacuum chamber 302 to obtain decomposition of the first metal oxide 312.

The variable temperature control 310 is further configured to vary the stepped voltage to obtain decomposition of the second metal oxide 314.

In gaseous form, the metal oxides (e.g., the first metal oxide 312) that make up most of the regolith 308 decompose into suboxides, metal, and oxygen.

In various embodiments, the decomposed oxygen and metal(s) may then be siphoned from the vacuum chamber 302 and cooled to be used for life support, technology, and fuel.

The oxygen and metal(s) may need to be cooled immediately in order to prevent the metal(s) from recombining with the oxygen.

Oxygen will be the most critically produced component from the lunar regolith. Most lunar ISRU work revolves around the production and use of oxygen. Oxygen serves numerous purposes including allowing humans to inhabit the lunar surface to perform complex research and experiments, allowing for water storage with hydrogen to support human and plant life, and acting as a fuel source, both in terms of energy to support life, and as a propellant for rockets. The production of oxygen will be critical for survival on the Moon. With the vast applications and needs for oxygen it is beneficial that lunar regolith is approximately 45% oxygen by weight.

The system 300 thus provides a novel material processing technique based on an improved vapor phase pyrolysis (VPP) system, according to an embodiment, that will allow for a more refined processing of regolith. This in turn may provide more benefits for certain applications.

In some embodiments, the regolith 308 is lunar regolith.

In some embodiments, the regolith 308 is martian regolith.

In some embodiments, the regolith 308 is materials harvested from asteroid sources, planetoids, other celestial bodies or a combination thereof.

In some embodiments, the regolith 308, is materials from recycling space debris, satellites in orbit, or other materials transported from Earth to space.

Although this technique also requires high operating temperatures, a main attraction of this method is that it uses in-situ resources available on the Moon (e.g., lunar regolith) without requiring additives.

In some embodiments, the first metal oxide and second metal oxide each include a different one of potassium oxide (K2O), iron (III) oxide (Fe2O3), iron (II) oxide (FeO), sodium oxide (Na2O), chromium (III) oxide (Cr2O3), manganese (II) oxide (MnO), silicon dioxide (SiO2), titanium dioxide (TiO2), aluminium (III) oxide (Al2O3), magnesium oxide (MgO), and calcium oxide (CaO).

In some embodiments, the vacuum chamber 302 is powered at least in part by space-based solar power.

In some embodiments, the variable temperature control 310 is powered at least in part by space-based solar power.

As the temperature is needed to be greater than about 2000° C., a large amount of energy is required. Thus, solar power including space-based solar power (SBSP) may be used to provide such energy, at least partially.

Applying a stepped temperature method to VPP allows species to gasify and be collected subsequently, thereby advantageously reducing post processing of the material. Overall, with sufficient power, the proposed novel methods could provide a simpler way of obtaining high purity materials for desired applications by reducing the required post processing. Like other existing techniques, VPP shares the common goal of producing useable products from in-situ material on the lunar surface and has potential applications thereto.

In some embodiments, the system 300 further includes a siphoning apparatus configured to siphon decomposed oxygen and metal from the vacuum chamber 302.

Referring now to FIG. 4, shown therein is a method 400 of in-situ resource processing. In an embodiment, the method 400 is implemented in the system 300 of FIG. 3.

At 410, the method 400 includes providing regolith in vacuum chamber.

At 420, the method 400 further includes applying a stepped temperature to the vacuum chamber to obtain decomposition of a first metal oxide.

At 430, the method 400 further includes varying the stepped temperature to obtain decomposition of a second metal oxide.

In various embodiments, the regolith is lunar regolith.

In some embodiments, the first metal oxide and second metal oxide each include a different one of potassium oxide (K₂O), iron (III) oxide (Fe₂O₃), iron (II) oxide (FeO), sodium oxide (Na₂O), chromium (III) oxide (Cr₂O₃), manganese (II) oxide (MnO), silicon dioxide (SiO₂), titanium dioxide (TiO₂), aluminium (III) oxide (Al₂O₃), magnesium oxide (MgO), and calcium oxide (CaO).

In various embodiments, the regolith is martian regolith.

In some embodiments, the first metal oxide and second oxide each include but not limited to a different one of Silicone Oxides (SiO₂), Iron-oxides (Fe₂O₃, Fe₃O₄), Aluminum Oxides (Al₂O₃), Magnesium Oxides (MgO), SiO₂, TiO₂; alkali oxides such as sodium oxides (Na₂O) and potassium oxides K₂O, and/or Sulphur Oxides (SO₃).

In other embodiments the first and second oxides are harvested from waste processes.

In some embodiments, the vacuum chamber is powered at least in part by space-based solar power.

In some embodiments, a variable temperature control controlling the stepped temperature is powered at least in part by space-based solar power.

As the temperature is needed to be greater than about 2000° C., a large amount of energy is required. Thus, space-based solar power (SBSP) may be used to provide such energy, at least partially.

In some embodiments, the method 400 further includes siphoning decomposed oxygen and metal from the vacuum chamber.

There are several applications for the materials derived from lunar in-situ processing methods that will help to construct a habitable lunar environment in a more economic fashion than transporting all the required material from Earth.

Metals will be incredibly useful towards developing infrastructure necessary for lunar inhabitation and survival. Metals are often overlooked in discussions of ISRP as many groups focus primarily or only on the production of oxygen.

Metals and metallic alloys may be extracted from the lunar regolith which can be used in construction of lunar bases, vehicles, equipment, perovskites or other structures. Ideally, the produced metals and alloys could be formed immediately after processing as the hot processing methods could allow for the metallic product to be easily shaped into whatever form is desired. For example, it may be ideal if the hot metallic products could be cast into molds for beams, and/or metal foam or liquids in construction, or for bricks in roads or launchpads. It is of note that casting is also a high-energy process, similar to the regolith processing methods described previously.

Similarly, silicon-based products will be important for the development of a lunar infrastructure. Silicon materials such as glass or ceramics will serve many applications on the lunar surface. Silicon is the primary element in solar power collectors and can be used to create solar panels for future energy production. Silicon-based glass could also be formed to produce equipment needed for experiments, or for the construction of lunar habitats. Silicon-based ceramics could be used to create electronic devices, casings or tiles, solar cells, elements related to wireless power transmission such as transceivers. These could be used as vehicles or equipment components or even as floor tiling for people or equipment. As silicon dioxide is the largest component of lunar regolith, it will be important to utilize it effectively as a source material.

It is also important to note that all of the products derived from in-situ lunar regolith can be used to support the development and maintenance of SBSP. As previously mentioned, silicon could be used with to other additives to create solar cells for energy production. Metals could be used to create a based structure to construct a solar array upon to either be used on the lunar surface or in orbit in SBSP. Oxygen could be use as a fuel to transport the newly created solar array into orbit as a standalone structure, or to be combined and build upon existing SBSP. In a similar way these components can be used to maintain SBSP. If the structure of an array is decaying, it could be replaced using metals derived from regolith. If a solar cell has been damaged and could potentially damage the rest of the array, it could be replaced. This use of in-situ material to create and maintain energy producing technology creates a production cycle that is more independent from earth and less dependent on materials being brought to the lunar surface.

In some embodiments, metals and metallic alloys may be sourced from Earth. In other embodiments, sources may include recycling space debris, retired satellites in orbit, second stages, empty fuel tanks, or other materials transported from Earth to space. In other examples, metal and metal alloys may be sourced from space. Sources may also include materials from the Mars (martian regolith), asteroid sources, planetoids, other celestial bodies or a combination thereof.

While the above description provides examples of one or more apparatus, methods, or systems, it will be appreciated that other apparatus, methods, or systems may be within the scope of the claims as interpreted by one of skill in the art.

Elements of each embodiment may be incorporated into other embodiments, for example, configurations discussed in relation to one embodiment, may be applied to other embodiments disclosed herein.

Further, it is evident that various modifications and combinations can be made without departing from the invention. The specification and drawings are, accordingly, to be regarded simply as an illustration of the invention as defined by the claims, and are contemplated to cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present disclosure.