SYSTEMS AND METHODS FOR EM-ASSISTED IN-SITU BIOMINING

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63/698,055, filed on Sep. 24, 2024, the entire disclosure of which is incorporated herein by reference for all purposes.

TECHNICAL FIELD

This disclosure generally relates to systems and methods for electromagnetic (EM)-assisted in-situ biomining.

BACKGROUND

Modern mining techniques can be generally categorized into three types: open pits (“surface mining”), underground mining, and in-situ mining. Over time, there are less materials available close to the surface, making surface mining less useful for reaching desirable materials, such as metals, including but not limited to copper, lithium, gold, uranium, rare earth elements (REE), and the like. Long-term sustainability is also an issue with open pit and underground mining. For example, these techniques may significantly impact local soil, water, and air quality. Also, there are concerns about safety, such as a dam bursting, earth moving, or holes in the ground causing problems when using open pit and traditional underground mining. In contrast, in-situ mining, also known as in-situ leaching, in-situ recovery, solution mining, etc., is scalable to smaller or larger deposits of target materials, requires lower capital and operation cost than open pits or underground mining that requires large equipment, has a smaller overall environmental impact than the other mining techniques, and is safer than the other mining techniques.

SUMMARY

This disclosure pertains to systems and methods for electromagnetic (EM)-assisted in-situ biomining.

A first aspect of this disclosure pertains to a method for in-situ mining in a rock formation in an area of interest, the method including: receiving a first micro-organism from a micro-organism source at a first well extending downward from a ground surface in the area of interest, injecting the first micro-organism into a permeable layer of the rock formation via the first well to dissolve a target material to form a solution containing the first micro-organism and the target material, applying an electric field to the first micro-organism by the first well operating as a first electrode and a second well operating as a second electrode, such that the electric field stimulates activity of the first micro-organism to form the solution, receiving the solution via the second well extending downward from the ground surface in the area of interest, and pumping the solution, via the second well, to a processing plant to separate the target material from the first micro-organism.

A second aspect of this disclosure pertains to the method of the first aspect, wherein stimulating activity of the first micro-organism comprises one or more of: enhancing growth of the first micro-organism; increasing a rate of the first micro-organism's dissolving the target material; or directing where in the rock formation the first micro-organism travels.

A third aspect of this disclosure pertains to the method of any preceding aspect, and further includes applying the electric field at a high intensity to suppress or kill the first micro-organism.

A fourth aspect of this disclosure pertains to the method of any preceding aspect, wherein the electric field is applied according to a timing sequence.

A fifth aspect of this disclosure pertains to the method of any preceding aspect, and further includes: injecting a second micro-organism to further suppress or kill the first micro-organism, wherein the second micro-organism is a different species from the first micro-organism, and wherein the second micro-organism is benign to a local environment or microbiome.

A sixth aspect of this disclosure pertains to the method of any preceding aspect, and further includes: injecting a second micro-organism after the first micro-organism is suppressed or killed, the second micro-organism being a different species from the first micro-organism, applying another electric field to the second micro-organism by the first well operating as the first electrode and the second well operating as the second electrode, such that the another electric field stimulates activity of the second micro-organism to further form the solution, receiving the solution via the second well, and pumping the solution, via the second well, to the processing plant to separate the target material from the second micro-organism.

A seventh aspect of this disclosure pertains to the method of any preceding aspect, and further includes: injecting a lixiviant into the rock formation via the first well before, with, or after the injecting the first micro-organism, wherein the solution further includes the target material dissolved by the lixiviant.

An eighth aspect of this disclosure pertains to the method of any preceding aspect, wherein the separating the target material from the first micro-organism includes one or more of: an electrowinning process, an electroextraction process, or a precipitation process.

A ninth aspect of this disclosure pertains to the method of any preceding aspect, wherein the electric field is applied to the rock formation at one or more of: directly after the injecting of the first micro-organism or after the first micro-organism has had time to leach the target material.

A tenth aspect of this disclosure pertains to the method of any preceding aspect, and further includes applying an initializing electric field to kill any pre-existing micro-organisms before the injecting of the first micro-organism.

An eleventh aspect of this disclosure pertains to the method of any preceding aspect, wherein the first micro-organism includes one or more of: Acidithiobacillus, Acidiphilium, Acidocella, Acidiferrobacter, Leptospirillum, Alicyclobacillus, Sulfobacillus, Nitrospira, Ferroplasma, Acidiplasma, Cuniculiplasma, Sulfolobus, Sulfuracidifex, Acidianus, Metallosphaera, or Sulfurisphaera.

A twelfth aspect of this disclosure pertains to the method of any preceding aspect, and further includes: in a first phase, the injecting the first micro-organism into the rock formation includes injecting a first set of micro-organisms including one or more first species of micro-organisms, after the first phase is complete, applying a high-intensity electric field to kill the first set of micro-organisms, subsequently, in a second phase, injecting a second set of micro-organisms into the rock formation, the second set of micro-organisms including one or more second species of micro-organisms, and after the second phase is complete, applying a high-intensity electric field to suppress or kill the second set of micro-organisms.

A thirteenth aspect of this disclosure pertains to the method of the twelfth aspect, wherein: the one or more second species of micro-organisms is a same one or more species as the one or more first species of micro-organisms, or the one or more second species of micro-organisms is different from the one or more first species of micro-organisms.

A fourteenth aspect of this disclosure pertains to the method of any preceding aspect and further includes: applying a high-intensity electric field to kill the first micro-organism, and injecting a second micro-organism into the rock formation via the first well to further dissolve the target material.

A fifteenth aspect of this disclosure pertains to a system for in-situ mining in a rock formation in an area of interest, including: a first well extending downward from a ground surface in the area of interest, the first well being configured to: receive a first micro-organism from a micro-organism source, inject the first micro-organism into a permeable layer of the rock formation to dissolve a target material to form a solution containing the first micro-organism and the target material, and operate as a first electrode to an electric field to the first micro-organism, and a second well extending downward from the ground surface in the area of interest, the second well being configured to: receive the solution, operate as a second electrode to apply the electric field to the first micro-organism, and pump the solution to a processing plant to separate the target material from the first micro-organism, wherein the electric field stimulates activity of the first micro-organism to form the solution.

A sixteenth aspect of this disclosure pertains to the system of the fifteenth aspect, wherein stimulating activity of the first micro-organism comprises one or more of: enhancing growth of the first micro-organism; increasing a rate of the first micro-organism's dissolving the target material; or directing where in the rock formation the first micro-organism travels.

A seventeenth aspect of this disclosure pertains to the system of any preceding aspect, wherein the first and second wells are further configured to apply the electric field at a high intensity to suppress or kill the first micro-organism.

An eighteenth aspect of this disclosure pertains to the system of any preceding aspect, wherein the first and second wells are further configured to apply the electric field according to a timing sequence.

A nineteenth aspect of this disclosure pertains to the system of any preceding aspect, wherein: the first well is further configured to inject a second micro-organism to further suppress or kill the first micro-organism, the second micro-organism is a different species from the first micro-organism, and the second micro-organism is benign to a local environment or microbiome.

A twentieth aspect of this disclosure pertains to the system of any preceding aspect, wherein: the first well is further configured to inject a second micro-organism after the first micro-organism is suppressed or killed, the second micro-organism being a different species from the first micro-organism, the first and second wells are further configured to apply another electric field to the second micro-organism by the first well operating as the first electrode and the second well operating as the second electrode, such that the another electric field stimulates activity of the second micro-organism to further form the solution, and the second well is further configured to: receive the solution, and pump the solution to a processing plant to separate the target material from the second micro-organism.

A twenty-first aspect of this disclosure pertains to the system of any preceding aspect, wherein: the first well is further configured to: inject a lixiviant into the rock formation before, with, or after the injection of the first micro-organism, and the solution further includes the target material dissolved by the lixiviant.

A twenty-second aspect of this disclosure pertains to the system of any preceding aspect, wherein the separating the target material from the first micro-organism includes one or more of: an electrowinning process, an electroextraction process, or a precipitation process.

A twenty-third aspect of this disclosure pertains to the system of any preceding aspect, wherein the first and second wells are further configured to apply the electric field to the rock formation at one or more of: directly after the injecting of the first micro-organism or after the first micro-organism has had time to leach the target material.

A twenty-fourth aspect of this disclosure pertains to the system of any preceding aspect, wherein the first and second wells are further configured to apply an initializing electric field to kill any pre-existing micro-organisms before the injection of the first micro-organism.

A twenty-fifth aspect of this disclosure pertains to the system of any preceding aspect, wherein the first micro-organism includes one or more of: Acidithiobacillus, Acidiphilium, Acidocella, Acidiferrobacter, Leptospirillum, Alicyclobacillus, Sulfobacillus, Nitrospira, Ferroplasma, Acidiplasma, Cuniculiplasma, Sulfolobus, Sulfuracidifex, Acidianus, Metallosphaera, or Sulfurisphaera.

A twenty-sixth aspect of this disclosure pertains to the system of any preceding aspect, wherein: the first well is further configured such that, in a first phase, the injecting the first micro-organism into the rock formation includes injecting a first set of micro-organisms including one or more first species of micro-organisms, the first and second wells are further configured to, after the first phase is complete, apply a high-intensity electric field to kill the first set of micro-organisms, the first well is further configured to, subsequently in a second phase, inject a second set of micro-organisms into the rock formation, the second set of micro-organisms including one or more second species of micro-organisms, and the first and second wells are further configured to, after the second phase is complete, apply a high-intensity electric field to suppress or kill the second set of micro-organisms.

A twenty-seventh aspect of this disclosure pertains to the system of the twenty-sixth aspect, wherein: the one or more second species of micro-organisms is a same one or more species as the one or more first species of micro-organisms, or the one or more second species of micro-organisms is different from the one or more first species of micro-organisms.

A twenty-eighth aspect of this disclosure pertains to the system of any preceding aspect, wherein: the first and second wells are further configured to apply a high-intensity electric field to kill the first micro-organism, and the first well is further configured to inject a second micro-organism into the rock formation via the first well to further dissolve the target material.

This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

Additional features and advantages of embodiments of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of such embodiments. The features and advantages of such embodiments may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features will become more fully apparent from the following description and appended claims or may be learned by the practice of such embodiments as set forth hereinafter.

BRIEF DESCRIPTION OF DRAWINGS

To describe the manner in which the above-recited and other features of the disclosure can be obtained, a more particular description will be rendered by reference to specific implementations thereof which are illustrated in the appended drawings. For better understanding, the like elements have been designated by like reference numbers throughout the various accompanying figures. While some of the drawings may be schematic or exaggerated representations of concepts, at least some of the drawings may be drawn to scale. Understanding that the drawings depict some example implementations, the implementations will be described and explained with additional specificity and detail through the use of the accompanying drawings.

FIG. 1 is a cross-sectional diagram of an in-situ mining operation according to a related art.

FIG. 2 is a diagram of electrokinetic in-situ leaching (EK-ISL) for an in-situ mining operation according to a related art.

FIG. 3 is a set of schematic views of bioleaching pathways according to a related art.

FIG. 4 is a flowchart of an electromagnetic (EM)-assisted in-situ biomining operation in accordance with an example embodiment of the present disclosure.

FIG. 5 illustrates certain components that may be included within a computer system according to an example embodiment of the present disclosure.

Before explaining the disclosed embodiments of this disclosure in detail, it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown, as the invention is capable of other embodiments. Example embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than limiting. Also, the terminology used herein is for the purpose of description and not of limitation.

DETAILED DESCRIPTION

While the subject disclosure applies to embodiments in many different forms, specific embodiments are shown in the drawings and will be described in detail herein with the understanding that the present disclosure is an example of the principles of the invention. It is not intended to limit the invention to the specific illustrated embodiments. The features of the invention disclosed herein in the description, drawings, and claims can be significant, both individually and in any desired combination, for the operation of the invention in its various embodiments. Features from one embodiment can be used in other embodiments of the invention. In the description of the drawings, like reference numerals refer to like elements.

In-Situ mining traditionally includes providing a series of wells, including injectors (or “injection wells”), producers (or “production wells”), and control wells (or “monitor wells”). One or more ores are contacted with a lixiviant, which acts to free one or more target materials from the ore, thereby enriching a solution being circulated from the injection to the production well. The extraction of target materials by this technique requires that the target materials be soluble, e.g., potash, potassium chloride, sodium chloride, sodium sulfate, which dissolve in water. Some materials, such as copper minerals, lithium, and uranium oxide, require a liquid medium as a lixiviant, such as acid or carbonate solutions, or a brine, to dissolve. Gold, for example, may use cyanide, chlorine, bromine, or iodine as a lixiviant. An oxidant, such as oxygen and/or hydrogen peroxide mixed with sodium carbonate or carbon dioxide, may be used as a lixiviant for uranium. The lixiviant is injected into the target material via one or more injection wells. The target material is dissolved by the lixiviant and the lixiviant mixed with the target material, which may be referred to as a “pregnant lixiviant” or “pregnant solution” is pumped via one or more production wells to the surface. The pregnant lixiviant is then processed to separate the target material from the lixiviant to recover the target material. Different patterns of injection and production wells can be used. Control wells are usually drilled around the injection and production wells to ensure that groundwater is not contaminated.

FIG. 1 is a cross-sectional diagram of an in-situ mining operation according to a related art.

FIG. 1 shows a mining area 100 in which control wells 105, 110, 115 are on a periphery of the mining area 100 to monitor for groundwater contamination. The control wells 105, 110, 115 can pass through and/or end at any of the various layers of the ground, e.g., a top layer 120, sands/clays/gravels 125, an upper clay layer 130, a target layer 135, and/or a lower clay layer 140. An injection well 145 pumps the lixiviant from a production plant (not shown) from the surface into the permeable target layer 135. A production well 150 pumps the pregnant lixiviant solution containing the target material from the target layer 135 back to the production plant on the surface.

FIG. 2 is a diagram of electrokinetic in-situ leaching (EK-ISL) for an in-situ mining operation according to a related art.

Electrokinetic in-situ leaching (EK-ISL) may be used to assist the in-situ mining process. A description of EK-ISL is made by Evelien Martens et al., “Toward a more sustainable mining future with electrokinetic in situ leaching,” Science Advances, 7, eabf9971 (2021), DOI: 10.1126/sciadv.abf9971, pp. 1-10 (https://www.science.org/doi/10.1126/sciadv.abf9971). FIG. 2, which was published in the above reference, provides a 3D isometric view of an industrial-scale EK-ISL operation in Part (a), including potential electrode configuration, above-ground energy source, lixiviant supply and recovery reservoirs connected to vertical wells, and metal recovery treatment facility. Part (b) shows a cross-sectional view of the ore interface between an anode well and a cathode well. Part (c) illustrates principal hydrogeochemical reactions between the lixiviant and the ore material when subjected to EK-driven electromigration.

When using EK-ISL, an electric field is created between a first well (or “borehole”) acting as an anode and a second well acting as a cathode. This is generally performed by applying a low-voltage DC current. EK-ISL is combined with the injection of lixiviant to help the lixiviant reach the metal and/or metal-rich minerals in the rocks, then EK-ISL controls the transport of the pregnant solution to the production well.

FIG. 3 is a set of schematic views of bioleaching pathways according to a related art.

In-Situ mining traditionally relies on a lixiviant (e.g., an acid) circulating through an ore body from injector (or injection) well(s) to producer (or production) well(s) to dissolve a target material. For example, the lixiviant may be used to leach one or more target materials, e.g., metals, from fractures in a rock formation. However, biological micro-organisms may be used with or in place of a traditional lixiviant to perform biomining, also referred to as “bioleaching.” Bioleaching leverages various micro-organisms to assist leaching. Some examples of metals that may be recovered by biomining include copper, nickel, and cobalt. As an example, bioleaching may be used in sulfide leaching operations. FIG. 3 shows schematic views of thiosulfate and polysulfide pathways in bioleaching of metal sulfides. An example bioleaching mechanism may involve ferrooxidans (Af) and L. ferrooxidans (Lf) and At. thiooxidans (At). Part (a) of FIG. 3 illustrates a thiosulfate mechanism. Part (b) of FIG. 3 illustrates a polysulfide mechanism. Additional details of these mechanisms can be found in Vera, M., et al., “Progress in bioleaching: fundamentals and mechanisms of microbial metal sulfide oxidation—part A.” Appl Microbiol Biotechnol. 2022 November; 106(21): 6933-6952. doi: 10.1007/s00253-022-12168-7. Epub 2022 Oct. 4. Erratum in: Appl Microbiol Biotechnol. 2022 November; 106(21): 7375. doi: 10.1007/s00253-022-12233-1. PMID: 36194263; PMCID: PMC9592645.

One risk associated with bioleaching is unwanted acid mine drainage (or acid rock drainage) caused by the micro-organisms after the mine operations have ceased. Acid mine drainage, acid and metalliferous drainage (AMD), or acid rock drainage (ARD) is the outflow of acidic water from metal mines and coal mines. To avoid the micro-organisms' being able to cause ARD after the mining operation has ceased typically involves killing the micro-organisms so they cannot continue to act on the rock formation. Cleanup of a bioleaching operation typically includes injecting chemicals into the mine to kill any remaining living micro-organisms, which can cause damage to the surrounding environment, and may even pollute the local aquifers and/or waterways. In addition, use of such chemicals may require permits from governmental organizations, which can add time, cost, and additional oversight to the project. The killed micro-organisms may or may not be flushed from the mine, and any chemicals used to kill the micro-organisms that are flushed must be handled in accordance with appropriate safety procedures.

The effect of electric fields on micro-organisms has been studied extensively in the medical field, and to a lesser extent in the context of soil remediation. Depending on the nature of the applied current, e.g., direct current (DC), alternating current (AC), and various frequencies of AC or DC current, the intensity of application of the electric field, and the duration of application of the electric field, the effects on micro-organisms can be negligible, can cause an increase in activity of micro-organisms, or can cause death of the micro-organisms.

FIG. 4 is a flowchart of an electromagnetic (EM)-assisted in-situ biomining operation in accordance with an example embodiment of the present disclosure.

With reference to FIG. 4, a method 400 for in-situ mining in a rock formation in an area of interest is described. The method 400 includes, in operation 410, receiving a first micro-organism from a micro-organism source at a first well extending downward from a ground surface in the area of interest. The method 400 further includes injecting the first micro-organism into the rock formation via the first well to dissolve a target material to form a solution containing the first micro-organism and the target material in operation 420. In operation 430, the method 400 further includes applying an electric field to the first micro-organism by the first well operating as a first electrode and a second well operating as a second electrode, such that the electric field stimulates activity of the first micro-organism to form the solution. Next, the method 400 includes receiving the solution via the second well extending downward from the ground surface in the area of interest (operation 440). Then, in operation 450, the method 400 includes pumping the solution, via the second well, to a processing plant to separate the target material from the first micro-organism.

In an enhanced in-situ biomining operation in accordance with an example embodiment of the present disclosure, micro-organisms are injected in the rock formation by an injection well, e.g., injection well 145 of FIG. 1, where they can accelerate leaching and/or help reach higher levels of metal recovery. A lixiviant may also be injected for additional leaching functionality. However, the use of micro-organisms may decrease the total amount of lixiviant that needs to be injected into the well, or may eliminate the need for a lixiviant.

Acidophilic micro-organisms, such as Acidithiobacillus ferrooxidans, are commonly used in biomining operations. These bacteria can assist the leaching of metals from sulfide minerals, such as chalcopyrite. After the bioleaching process, conventional methods, such as electrowinning, electroextraction, or precipitation, may be used to extract the metals from the solution. The EM-assisted in-situ biomining process could help boost microbial activity and improve metal extraction efficiency. An electric field may stimulate growth of a micro-organism, may cause the micro-organism to function faster, more efficiently, or more effectively, or may affect which direction the micro-organism spreads or travels. For example, the electric field may control a direction of the activity of the micro-organism, e.g., into some cracks or fissures in a rock formation or to avoid other locations. An example of an EM-assisted in-situ biomining operation in accordance with an example embodiment may include the leaching of copper in chalcopyrite-rich ores. It should be appreciated that embodiments are not limited only to copper leaching and leaching of metals from sulfide minerals. For example, any material capable of being leached and recovered from a micro-organism may be the target material. Furthermore, any micro-organism capable of leaching a target material may be used according to example embodiments.

For an EM-assisted in-situ biomining operation in accordance with an example embodiment, an electric field may be applied to the micro-organisms continuously or intermittently when the micro-organisms are initially injected. In another example, an electric field may be applied to the micro-organisms continuously or intermittently after the micro-organisms have been allowed to work their natural process for some duration. The duration may be, for example, hours, days, or weeks, depending on the natural leaching function speed of the micro-organisms. In another example, an electric field may be applied before the micro-organisms are introduced, in which case, the electric field may be applied, for example, to a previously-injected lixiviant. The electric field may be applied before the micro-organisms are introduced to pre-clean the rock formation to kill any naturally-occurring micro-organisms, or to kill previously-introduced micro-organisms, before a new micro-organism is injected into the rock formation. In another example, the electric field may be applied at the end of the usage period for the micro-organism to suppress or kill the micro-organism. For example, a high-intensity electric field may be used to suppress or kill the micro-organism. In one example an AC electric field may be applied. For example, less power may be needed to kill the micro-organism with an AC electric field than with a DC electric field.

An EM-assisted in-situ biomining operation in accordance with an example embodiment may include replacement and remediation of the micro-organisms. Several species of micro-organisms can be used as part of a biomining operation. Non-limiting examples of such micro-organisms include Acidithiobacillus, Acidiphilium, Acidocella, Acidiferrobacter, Leptospirillum, Alicyclobacillus, Sulfobacillus, Nitrospira, Ferroplasma, Acidiplasma, Cuniculiplasma, Sulfolobus, Sulfuracidifex, Acidianus, Metallosphaera, Sulfurisphaera, etc. In an example in-situ biomining operation, in a first phase of the biomining operation, a first set of micro-organisms including one or more species of micro-organisms may be injected into the rock formation. When the first phase is complete, a high-intensity electric field can be applied to kill the first set of micro-organisms. Subsequently, in a second phase of the biomining operation, a second set of micro-organisms including one or more species of micro-organisms may be injected into the rock formation. The second set of micro-organisms may be the same one or more species as the first set of micro-organisms, or may be a different one or more species from the first set. When the second phase is complete, a high-intensity electric field can be applied to kill the second set of micro-organisms. As such, a high-intensity electric field can be applied to kill the micro-organisms between phases before a new set of micro-organisms is introduced.

In an example embodiment, an electric field may be applied before the introduction of specially selected micro-organisms in the rock formation, for example, to “clean” the rock formation and have a more predictable behavior of the newly introduced bacteria. This “cleaning” could be for an electrical purpose, a chemical purpose, a microbial purpose, or any combination thereof.

One known issue with biomining is the risk of unwanted acid mine drainage. For example, if the micro-organisms remain in the formation beyond the completion of the mining operations, there is a risk of their creating unwanted acid mine drainage over time, which may take years. The traditional remediation technique is to inject a chemical to raise the pH of the mine environment to kill the micro-organisms. However, in an example embodiment, applying a high-intensity electric field is an alternative way to kill the micro-organisms. Alternatively, in an example embodiment, different types of micro-organisms or combinations of different types of micro-organisms that are “friendly” or benign to a local environment or microbiome could be introduced to nullify or counter the effects of the electric field, or micro-organisms, or chemicals used for in-situ mining.

In an EM-assisted biomining operation in accordance with an example embodiment of the present disclosure, the anode-cathode system may be the same or different from that used to transport a traditional lixiviant. An example anode-cathode system can be designed to a) help transport the lixiviant active ingredients and the pregnant lixiviant metals, b) enhance in-situ biomining (e.g., via electromigration), and c) ensure proper remediation.

In an example embodiment, an electric field may be applied in a sequence by changing timing, duration, type (e.g., AC and DC), intensity, and/or frequencies of the electric field. The electric field may be applied intermittently or continuously. The sequence of electric field applications can be selected and/or optimized based on the objectives of the operation, for example, to help transport the lixiviant active ingredients and the pregnant lixiviant metals, to enhance in-situ biomining, and/or to ensure proper remediation. In an example embodiment, a sequence of electric field application can be combined with a sequence of introduction of different micro-organisms. For example, different electric field sequences may be applied for different micro-organisms that are introduced in different phases of a biomining operation.

To improve or optimize the sequence(s) of electric field and/or microorganism application, a predetermined model can be used based on a classification of mining projects. For example, a “standard” or predetermined sequence can be defined for copper oxide formations; another “standard” or predetermined sequence can be defined for chalcopyrite-dominated formations; and another “standard” or predetermined sequence can be defined for malachite-rich formations. Then the sequence can be (optionally) adjusted based on data received from the in-situ mine. In one example, the adjustment can rely on data acquired before leaching starts, e.g., data in the same mining project, or in other mining projects, particularly if geological analogs exist. In another example, the adjustment can rely on data acquired as the leaching operation proceeds, e.g., “real-time data,” which may include, but is not limited to, at least one of: a concentration of an active ingredient in a lixiviant, a concentration of metal(s) in a “pregnant” lixiviant solution, a concentration of a given variety of micro-organism, a pH, a temperature, an intensity of an electric current, an induced magnetic effect, etc. In another example, the adjustment may be based on data received both before and during the leaching operation. When data is available to be received from the in-situ mine, an improved or optimized sequence can be derived, for example, either by adjusting the parameters of a pre-selected model to best fit the data (e.g., a “parametric model” that accounts for the physics of the problem) or by building a model directly from the received data (e.g., a “data model’). Additionally, micro-organisms, which may be the same or different than those used for bioleaching, could be used to manage a chemical composition or a concentration (e.g., pH) in the vicinity of either or both of the electrodes.

In a similar manner to operations in which the micro-organisms are injected directly into the rock formation, a separate (e.g, surface-mounted) bioreactor may be used. The bioreactor may prevent the micro-organisms from inhabiting the downhole volume. For example, the micro-organisms may convert and/or regenerate ferrous to ferric iron so that the micro-organisms can interact again with the desired ore. A sterilization means and/or filtration may be applied to prevent the micro-organism from colonizing the mine. For example, a high-intensity electric field and/or a chemical may be applied to kill the micro-organism.

An interesting aspect of example embodiments of the present disclosure is a dual effect of the electric field. On the one hand, an electric field can stimulate micro-organism activity, e.g., accelerating the leaching process. On the other hand, a high-intensity electric field could suppress or even kill the micro-organisms. A threshold or operating curve, dependent on the electric field intensity, may allow for optimal selection of the electric field strength to either promote or inhibit micro-organism activity. Applying such a threshold or operating curve may help improve or optimize the control sequence for applying the electric field and injecting the micro-organisms.

FIG. 5 illustrates certain components that may be included within a computer system 500, which may be used to control features according to embodiments of the present disclosure, such as the features discussed with reference to FIGS. 1-4. One or more computer systems 500 may be used to implement the various devices, components, and systems described herein.

The computer system 500 includes one or more processors 501. The processor(s) 501 may be a single processor or may include multiple processors and/or sub-processors. The processor(s) 501 may be a general-purpose single- or multi-chip microprocessor (e.g., an Advanced RISC (Reduced Instruction Set Computer) Machine (ARM)), a special-purpose microprocessor (e.g., a digital signal processor (DSP)), a microcontroller, a programmable gate array, etc. The processor(s) 501 may be referred to as a central processing unit (CPU). Although a single processor(s) 501 is shown in the computer system 500 of FIG. 5, in an alternative configuration, a combination of processors (e.g., an ARM and DSP) could be used. In one or more embodiments, the computer system 500 further includes one or more graphics processing units (GPUs), which can provide processing services related to both entity classification and graph generation.

The computer system 500 also includes memory 503 in electronic communication with the processor(s) 501. The memory 503 may be any electronic component capable of storing electronic information. For example, the memory 503 may be embodied as random access memory (RAM), read-only memory (ROM), magnetic disk storage media, optical storage media, flash memory devices in RAM, on-board memory included with the processor, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, at least one non-transitory computer-readable and/or processor-readable medium, and so forth, including combinations thereof. The memory may include a single memory device or multiple memory devices.

Instructions 505 and data 507 may be stored in the memory 503. The instructions 505 may be executable by the processor(s) 501 to implement some or all of the functionality disclosed herein. Executing the instructions 505 may involve the use of the data 507 that is stored in the memory 503. Any of the various examples of modules and components described herein may be implemented, partially or wholly, as instructions 505 stored in memory 503 and executed by the processor(s) 501. Any of the various examples of data described herein may be among the data 507 that is stored in memory 503 and used during execution of the instructions 505 by the processor(s) 501.

A computer system 500 may also include one or more communication interfaces 509 for communicating with other electronic devices. The communication interface(s) 509 may be based on wired communication technology, wireless communication technology, or both. Some examples of communication interfaces 509 include a Universal Serial Bus (USB), an Ethernet adapter, a wireless adapter that operates in accordance with an Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless communication protocol, a Bluetooth® wireless communication adapter, and an infrared (IR) communication port.

A computer system 500 may also include one or more input devices 511 and one or more output devices 513. Some examples of input devices 511 include a keyboard, mouse, microphone, remote control device, button, joystick, trackball, touchpad, and lightpen. Some examples of output devices 513 include a speaker and a printer. One specific type of output device that is typically included in a computer system 500 is a display device 515. Display devices 515 used with embodiments disclosed herein may utilize any suitable image projection technology, such as liquid crystal display (LCD), light-emitting diode (LED), gas plasma, electroluminescence, or the like. A display controller 517 may also be provided, for converting data 507 stored in the memory 503 into text, graphics, and/or moving images (as appropriate) shown on the display device 515.

The various components of the computer system 500 may be coupled together by one or more buses, which may include a power bus, a control signal bus, a status signal bus, a data bus, etc. For the sake of clarity, the various buses are illustrated in FIG. 5 as a bus system 519.

Following are sections in accordance with at least one embodiment of the present disclosure:

Clause 1: A method for in-situ mining in a rock formation in an area of interest, the method including: receiving a first micro-organism from a micro-organism source at a first well extending downward from a ground surface in the area of interest, injecting the first micro-organism into a permeable layer of the rock formation via the first well to dissolve a target material to form a solution containing the first micro-organism and the target material, applying an electric field to the first micro-organism by the first well operating as a first electrode and a second well operating as a second electrode, such that the electric field stimulates activity of the first micro-organism to form the solution, receiving the solution via the second well extending downward from the ground surface in the area of interest, and pumping the solution, via the second well, to a processing plant to separate the target material from the first micro-organism.

Clause 2: The method of clause 1, wherein stimulating activity of the first micro-organism comprises one or more of: enhancing growth of the first micro-organism; increasing a rate of the first micro-organism's dissolving the target material; or directing where in the rock formation the first micro-organism travels.

Clause 3: The method of any preceding clause, further including applying the electric field at a high intensity to suppress or kill the first micro-organism.

Clause 4: The method of any preceding clause, wherein the electric field is applied according to a timing sequence.

Clause 5: The method of any preceding clause, further including: injecting a second micro-organism to further suppress or kill the first micro-organism, wherein the second micro-organism is a different species from the first micro-organism, and wherein the second micro-organism is benign to a local environment or microbiome.

Clause 6: The method of any preceding clause, further including: injecting a second micro-organism after the first micro-organism is suppressed or killed, the second micro-organism being a different species from the first micro-organism, applying another electric field to the second micro-organism by the first well operating as the first electrode and the second well operating as the second electrode, such that the another electric field stimulates activity of the second micro-organism to further form the solution, receiving the solution via the second well, and pumping the solution, via the second well, to the processing plant to separate the target material from the second micro-organism.

Clause 7: The method of any preceding clause, further including: injecting a lixiviant into the rock formation via the first well before, with, or after the injecting the first micro-organism, wherein the solution further includes the target material dissolved by the lixiviant.

Clause 8: The method of any preceding clause, wherein the separating the target material from the first micro-organism includes one or more of: an electrowinning process, an electroextraction process, or a precipitation process.

Clause 9: The method of any preceding clause, wherein the electric field is applied to the rock formation at one or more of: directly after the injecting of the first micro-organism or after the first micro-organism has had time to leach the target material.

Clause 10: The method of any preceding clause, further including applying an initializing electric field to kill any pre-existing micro-organisms before the injecting of the first micro-organism.

Clause 11: The method of any preceding clause, wherein the first micro-organism includes one or more of: Acidithiobacillus, Acidiphilium, Acidocella, Acidiferrobacter, Leptospirillum, Alicyclobacillus, Sulfobacillus, Nitrospira, Ferroplasma, Acidiplasma, Cuniculiplasma, Sulfolobus, Sulfuracidifex, Acidianus, Metallosphaera, or Sulfurisphaera.

Clause 12: The method of any preceding clause, further including: in a first phase, the injecting the first micro-organism into the rock formation includes injecting a first set of micro-organisms including one or more first species of micro-organisms, after the first phase is complete, applying a high-intensity electric field to kill the first set of micro-organisms, subsequently, in a second phase, injecting a second set of micro-organisms into the rock formation, the second set of micro-organisms including one or more second species of micro-organisms, and after the second phase is complete, applying a high-intensity electric field to suppress or kill the second set of micro-organisms.

Clause 13: The method of clause 12, wherein: the one or more second species of micro-organisms is a same one or more species as the one or more first species of micro-organisms, or the one or more second species of micro-organisms is different from the one or more first species of micro-organisms.

Clause 14: The method of any preceding clause, further including: applying a high-intensity electric field to kill the first micro-organism, and injecting a second micro-organism into the rock formation via the first well to further dissolve the target material.

Clause 15: A system for in-situ mining in a rock formation in an area of interest, including: a first well extending downward from a ground surface in the area of interest, the first well being configured to: receive a first micro-organism from a micro-organism source, inject the first micro-organism into a permeable layer of the rock formation to dissolve a target material to form a solution containing the first micro-organism and the target material, and operate as a first electrode to an electric field to the first micro-organism, and a second well extending downward from the ground surface in the area of interest, the second well being configured to: receive the solution, operate as a second electrode to apply the electric field to the first micro-organism, and pump the solution to a processing plant to separate the target material from the first micro-organism, wherein the electric field stimulates activity of the first micro-organism to form the solution.

Clause 16: The system of clause 15, wherein stimulating activity of the first micro-organism comprises one or more of: enhancing growth of the first micro-organism; increasing a rate of the first micro-organism's dissolving the target material; or directing where in the rock formation the first micro-organism travels.

Clause 17: The system of clause 14, wherein the first and second wells are further configured to apply the electric field at a high intensity to suppress or kill the first micro-organism.

Clause 18: The system of any preceding clause, wherein the first and second wells are further configured to apply the electric field according to a timing sequence.

Clause 19: The system of any preceding clause, wherein: the first well is further configured to inject a second micro-organism to further suppress or kill the first micro-organism, the second micro-organism is a different species from the first micro-organism, and the second micro-organism is benign to a local environment or microbiome.

Clause 20: The system of any preceding clause, wherein: the first well is further configured to inject a second micro-organism after the first micro-organism is suppressed or killed, the second micro-organism being a different species from the first micro-organism, the first and second wells are further configured to apply another electric field to the second micro-organism by the first well operating as the first electrode and the second well operating as the second electrode, such that the another electric field stimulates activity of the second micro-organism to further form the solution, and the second well is further configured to: receive the solution, and pump the solution to a processing plant to separate the target material from the second micro-organism.

Clause 21: The system of any preceding clause, wherein: the first well is further configured to: inject a lixiviant into the rock formation before, with, or after the injection of the first micro-organism, and the solution further includes the target material dissolved by the lixiviant.

Clause 22: The system of any preceding clause, wherein the separating the target material from the first micro-organism includes one or more of: an electrowinning process, an electroextraction process, or a precipitation process.

Clause 23: The system of any preceding clause, wherein the first and second wells are further configured to apply the electric field to the rock formation at one or more of: directly after the injecting of the first micro-organism or after the first micro-organism has had time to leach the target material.

Clause 24: The system of any preceding clause, wherein the first and second wells are further configured to apply an initializing electric field to kill any pre-existing micro-organisms before the injection of the first micro-organism.

Clause 25: The system of any preceding clause, wherein the first micro-organism includes one or more of: Acidithiobacillus, Acidiphilium, Acidocella, Acidiferrobacter, Leptospirillum, Alicyclobacillus, Sulfobacillus, Nitrospira, Ferroplasma, Acidiplasma, Cuniculiplasma, Sulfolobus, Sulfuracidifex, Acidianus, Metallosphaera, or Sulfurisphaera.

Clause 26: The system of any preceding clause, wherein: the first well is further configured such that, in a first phase, the injecting the first micro-organism into the rock formation includes injecting a first set of micro-organisms including one or more first species of micro-organisms, the first and second wells are further configured to, after the first phase is complete, apply a high-intensity electric field to kill the first set of micro-organisms, the first well is further configured to, subsequently in a second phase, inject a second set of micro-organisms into the rock formation, the second set of micro-organisms including one or more second species of micro-organisms, and the first and second wells are further configured to, after the second phase is complete, apply a high-intensity electric field to suppress or kill the second set of micro-organisms.

Clause 27: The system of clause 26, wherein: the one or more second species of micro-organisms is a same one or more species as the one or more first species of micro-organisms, or the one or more second species of micro-organisms is different from the one or more first species of micro-organisms.

Clause 28: The system of any preceding clause, wherein: the first and second wells are further configured to apply a high-intensity electric field to kill the first micro-organism, and the first well is further configured to inject a second micro-organism into the rock formation via the first well to further dissolve the target material.

Systems and software, e.g., implemented on a non-transitory computer-readable medium, for performing the methods discussed herein are also within the scope of embodiments of the present disclosure.

Embodiments of the present disclosure may thus utilize a special purpose or general-purpose computing system including computer hardware, such as, for example, one or more processors and system memory. Embodiments within the scope of the present disclosure also include physical and other computer-readable media for carrying or storing computer-executable instructions and/or data structures, including applications, tables, data, libraries, or other modules used to execute particular functions or direct selection or execution of other modules. Such computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer system. Computer-readable media that store computer-executable instructions (or software instructions) are physical storage media. Computer-readable media that carry computer-executable instructions are transmission media. Thus, by way of example, and not limitation, embodiments of the present disclosure can include at least two distinctly different kinds of computer-readable media, namely physical storage media or transmission media. Combinations of physical storage media and transmission media should also be included within the scope of computer-readable media.

Both physical storage media and transmission media may be used temporarily to store or carry software instructions in the form of computer readable program code that allows performance of embodiments of the present disclosure. Physical storage media may further be used to persistently or permanently store such software instructions. Examples of physical storage media include physical memory (e.g., RAM, ROM, EPROM, EEPROM, etc.), optical disk storage (e.g., CD, DVD, HDDVD, Blu-ray, etc.), storage devices (e.g., magnetic disk storage, tape storage, diskette, etc.), flash or other solid-state storage or memory, or any other non-transmission medium which can be used to store program code in the form of computer-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer, whether such program code is stored as or in software, hardware, firmware, or combinations thereof.

A “network” or “communications network” may generally be defined as one or more data links that enable the transport of electronic data between computer systems and/or modules, engines, and/or other electronic devices. When information is transferred or provided over a communication network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a computing device, the computing device properly views the connection as a transmission medium. Transmission media can include a communication network and/or data links, carrier waves, wireless signals, and the like, which can be used to carry desired program or template code means or instructions in the form of computer-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer.

Further, upon reaching various computer system components, program code in the form of computer-executable instructions or data structures can be transferred automatically or manually from transmission media to physical storage media (or vice versa). For example, computer-executable instructions or data structures received over a network or data link can be buffered in memory (e.g., RAM) within a network interface module (NIC), and then eventually transferred to computer system RAM and/or to less volatile physical storage media at a computer system. Thus, it should be understood that physical storage media can be included in computer system components that also (or even primarily) utilize transmission media.

One or more specific embodiments of the present disclosure are described herein. These described embodiments are examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, not all features of an actual embodiment may be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous embodiment-specific decisions will be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one embodiment to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

The articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements in the preceding descriptions. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. For example, any element described in relation to an embodiment herein may be combinable with any element of any other embodiment described herein. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.

A person having ordinary skill in the art should realize in view of the present disclosure that equivalent constructions do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions, and alterations may be made to embodiments disclosed herein without departing from the spirit and scope of the present disclosure. Equivalent constructions, including functional “means-plus-function” clauses are intended to cover the structures described herein as performing the recited function, including both structural equivalents that operate in the same manner, and equivalent structures that provide the same function. It is the express intention of the applicant not to invoke means-plus-function or other functional claiming for any claim except for those in which the words ‘means for’ appear together with an associated function. Each addition, deletion, and modification to the embodiments that falls within the meaning and scope of the claims is to be embraced by the claims. Any trademarks mentioned herein are the property of their respective owners. Example embodiments are not limited to any particularly-mentioned products, trademarks, or properties.

The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of a stated amount. Further, it should be understood that any directions or reference frames in the preceding description are merely relative directions or movements. For example, any references to “up” and “down” or “above” or “below” are merely descriptive of the relative position or movement of the related elements.

The present disclosure may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are to be considered as illustrative and not restrictive. The scope of the disclosure is, therefore, indicated by the appended claims rather than by the foregoing description. Changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.