Methods and materials for carbon dioxide removal using mining-influenced water bodies

Abstract

A method of measuring captured carbon from an atmosphere includes modeling a mining-influenced water body, measuring a carbon content of the mining-influenced water body, contacting the mining-influenced water with an alkaline material to form a mining- influenced water and alkaline mixture, measuring a parameter of the mining-influenced water and alkaline mixture over time, measuring the carbon content of the mining-influenced water body, and calculating the amount of carbon captured from the atmosphere.

Description

TECHNICAL FIELD

[0001] This disclosure relates to systems, methods, and materials in the use of mining-influenced water bodies for capture and storage of carbon dioxide from the atmosphere. BACKGROUND

[0002] Limiting global warming requires both drastic emissions reductions and large-scale removal of carbon dioxide (CO2) from the atmosphere. Deliberate, human-driven removal of CO2 from this atmosphere is nascent, and a suite of new technologies are needed to meet the scale of the problem. Simultaneously, open pit mining has been used for hundreds of years to extract, for example, coal, diamonds, construction aggregates, and ores containing metals such as copper, iron, and gold. After mine closure, these pits frequently fill with water, forming a pit lake which may be acidic with high concentrations of dissolved metals. Historically, many pit lakes were inadequately remediated because remediation is a pure cost. Similarly, other water bodies associated with mining may exhibit poor water quality, including tailings ponds, flooded underground workings, tailings dams, lined pits, sedimentation ponds, polishing ponds, sludge ponds, stratification ponds, and cooling ponds. Mining-influenced water bodies are infrequently put to beneficial use. Nutrient-poor or contaminated water typically limits the development of robust ecosystems even after cleanup and physical hazards often preclude their use for recreation. A profitable use of pit lakes has previously remained elusive.

[0003] Proposed methods of carbon dioxide removal (“CDR”) include direct air capture with carbon storage (“DACCS”), biochar, ocean alkalinity enhancement (“OAE”), enhanced rock weathering (“ERW”), and biotic techniques such as growing plants including algae, kelp, or -1- trees. In DACCS, air passes over a CO2 sorbent which is periodically regenerated, releasing a pure stream of CO2. The CO2 is then compressed and injected underground or used in manufacturing of other materials. Biochar involves pyrolyzing organic matter to create a recalcitrant form of carbon which can be used as a soil amendment or buried. In OAE, alkaline materials are added to seawater, enabling the ocean to absorb more CO2 from the atmosphere and store it as dissolved carbon. In ERW, finely ground alkaline silicate minerals are spread over land, accelerating the chemical reactions which naturally occur between the minerals, water, and air. Atmospheric CO2 reacts with dissolved minerals to form solid carbonates or flows to the ocean where it is stored as dissolved carbon. Finally, biotic means of CDR encourage the growth of plant matter, followed by a preservation step to sequester the embodied carbon. The preservation may occur by sinking to the deep ocean, burial, or pickling.

[0004] All methods of CDR currently under development suffer from some combination of high costs, high energy requirements, lack of durability, limited scalability, intractable measurements, environmental risk, lack of social license, or high land use. DACCS is durable and measurable, but has high cost, energy, and land requirements. Biochar is measurable and potentially inexpensive but has limited scalability and questions remain around durability. OAE is inexpensive, scalable, and durable, but measurements are impossible and risks to ecosystems are unknown, leading to low social license. Similarly, ERW is inexpensive, scalable, and durable, but requires large swathes of land, is difficult to measure, and may present risks to downstream ecosystems. Biotic CDR can be inexpensive and scalable but is plagued by questions of durability and measurability. What is needed is a new technology to overcome the constraints on existing CDR methods.

[0005] Neutralization of acidic mining-influenced water is conventionally performed by adding alkaline materials such as lime (CaO, Ca(OH)2, CaCOs), limestone, or trona. While -2- effective, these treatments emit CO2 into the atmosphere, either in the production of the materials (e.g., lime) or as the materials are dissolved in acid (carbonates). A less common alternative is the addition of nutrients and organic compounds to the water to produce conditions favorable for sulfate-reducing bacteria. While not as emissive as conventional treatments, this alternative is not optimized or intended to remove CO2 from the atmosphere.

[0006] A present need exists for a solution that neutralizes acidic mining-influenced water and also captures carbon dioxide from the atmosphere. SUMMARY

[0007] Embodiments disclosed herein relate to a method of capturing carbon from an atmosphere, the method comprising: modeling a mining-influenced water body; contacting the mining-influenced water with an alkaline material to form a mining-influenced water and alkaline mixture; measuring a parameter of the mining-influenced water and alkaline mixture over time; measuring the carbon content of the mining-influenced water body; and calculating the amount of carbon captured from the atmosphere. In one embodiment, the modeling further comprises geochemical modeling. In one embodiment, the modeling further comprises hydrological modeling. In one embodiment, the modeling further comprises integrating a weather forecast. In one embodiment, the mining-influenced water body further comprises a pond. In one embodiment, the mining-influenced water body further comprises a reservoir. In one embodiment, the mining-influenced water body further comprises a pit lake. In one embodiment, the mining-influenced water body further comprises a lined pit. In one embodiment, the method further comprises aerating the mining-influenced water and alkaline mixture. In one embodiment, the parameter comprises pH. In one embodiment, the parameter comprises conductivity. In one embodiment, the parameter comprises oxidation-reduction potential. In one embodiment, the parameter comprises organic carbon. In one embodiment, the parameter comprises ion concentration. In one embodiment, the parameter comprises sediment properties. In one embodiment, the method further comprises pre-screening the mining-influenced water body. In one embodiment, the method further comprises contacting the mining-influenced water and alkaline mixture with organic matter. In one embodiment, the method further comprises contacting the mining-influenced water and alkaline mixture with water comprising a partial pressure of carbon dioxide. In one embodiment, the method further comprises dissolving the alkaline material into the mining-influenced water by a method comprising: disposing a portion of the mining-influenced water and alkaline mixture into a separate system; further dissolving the alkaline in the mining-influenced water and alkaline mixture to form a mining-influenced water and alkaline solution in the separate system; and returning the mining-influenced water and alkaline solution from the separate system to the mining-influenced water body. In one embodiment, further dissolving the alkaline comprises mechanical milling. In one embodiment, further dissolving the alkaline comprises elevating a temperature of the mining-influenced water and alkaline mixture. In one embodiment, precipitation of sediments is accelerated prior to returning the mining-influenced water and alkaline solution to the mining-influenced water body. In one embodiment, contaminants are removed from the mining-influenced water and alkaline solution prior to returning the mining-influenced water and alkaline solution to the mining-influenced water body.

[0008] Objects, advantages and novel features, and further scope of applicability of the present embodiments will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice. The objects and advantages of the embodiments may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0009] FIG. 1A is a process diagram that illustrates a process of usage of mining-influenced water bodies for carbon removal, according to an embodiment of the present disclosure.

[0010] FIG. IB is a schematic drawing that illustrates a process for using mining-influenced water bodies for carbon removal, according to an embodiment of the present disclosure.

[0011] FIG. 2 is a process diagram that illustrates a process for using mining-influenced bodies for carbon removal including iterative updates, according to an embodiment of the present disclosure.

[0012] FIG. 3 is a diagram that illustrates a mine pit lake, according to an embodiment of the present disclosure.

[0013] FIG. 4 is a process diagram that illustrates a process for using mining-influenced bodies for carbon removal involving dissolving alkaline materials in mine water, according to an embodiment of the present disclosure.

[0014] FIG. 5 is a process diagram that illustrates a process for using mining-influenced bodies for carbon removal involving preparatory steps, according to an embodiment of the present disclosure.

[0015] FIG. 6A is a diagram that illustrates an aeration process using water droplets, according to an embodiment of the present disclosure.

[0016] FIG. 6B is a diagram that illustrates an aeration process using bubbles, according to an embodiment of the present disclosure.

[0017] FIG. 7 is a process diagram that illustrates a process of pumping elevated partial pressure of carbon dioxide (“pCOf’) water prior to adding alkaline materials, according to an embodiment of the present disclosure.

[0018] FIG. 8 is a process diagram that illustrates a process for using mining-influenced bodies for carbon removal involving contact with air, according to an embodiment of the present disclosure.

[0019] FIG. 9 illustrates a process diagram of a process for using mining-influenced bodies for carbon removal involving accelerating precipitation, according to an embodiment of the present disclosure.

[0020] FIG. 10 is a diagram that illustrates an example of materials layered at the bottom of a mining-influenced water body, according to an embodiment of the present disclosure.

[0021] FIG. 11 is a process diagram that illustrates a process for using mining-influenced bodies for carbon removal involving grinding alkaline materials with water, according to an embodiment of the present disclosure.

[0022] FIG. 12 is a graph that illustrates results from a geochemical model of a process for using mining-influenced bodies for carbon removal applied to a mine pit lake, according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0023] Embodiments disclosed herein provide systems and methods for a process of using mining-influenced bodies for carbon removal.

[0024] The discussion below uses several terms that have specific meanings. The definitions provided set out the meanings with the understanding that these definitions include reasonable variations of these meanings.

[0025] The term “mining-influenced water bodies” as used herein refers to man-made lakes, ponds, reservoirs, and lined pits produced as a result of mining operations. The discussion herein may refer to the water in these bodies as “mine water,” regardless of the nature of the mining-influenced water body.

[0026] The term “pit lake” as used herein comprises an open-pit surface mine which has become at least partially filled with water.

[0027] The terms “tailings” or “mine tailings” as used herein comprises materials remaining after separation of valuable materials from ore.

[0028] The term “tailings pond” as used herein comprises a pond, impoundment, or lined pit in which mine tailings are stored.

[0029] The term “carbon dioxide removal” (or “CDR”) as used herein refers to a process of deliberately extracting carbon dioxide (CO2) from the atmosphere and sequestering it in such a way that the CO2 does not return to the atmosphere over timescales of years to millennia.

[0030] The term “alkaline materials” as used herein refers to materials which dissolve in water to increase the alkalinity of the solution by releasing conservative metal ions including but not limited to, Ca2+, Mg2+, Na+, K+, or a combination thereof. Alkaline materials may include, but is not limited to oxides, hydroxides, silicates, carbonates, or amorphous composites of these metals.

[0031] The term “precipitated solids” as used herein comprises solid materials formed from the transformation of a dissolved substance into an insoluble compound.

[0032] The term “sediment” as used herein refers to solid materials that have settled to the bottom of a water body, including but not limited to precipitated solids formed as a result of a CDR process.

[0033] The term “contained water body” as used herein refers to a water body that, while having discharge or possible inflows, is not a free-flowing body of water such as a stream, river, or other naturally occurring body.

[0034] Embodiments disclosed herein include processes and methods of carbon dioxide removal. Generally the process involves pre-screening of a contained, mining-influenced water body, computer modeling of the chemistry and / or hydrology of the water body, generation and dispersal of one or more types of alkaline materials in the water body as needed, mixing of the alkaline materials into water body, aeration of the alkaline materials and / or the water, measurement of pH and inorganic carbon in the water and / or sediment, and calculation of total carbon removed from the atmosphere.

[0035] Referring now to the figures, in one embodiment as illustrated in FIG. 1A and FIG. IB, the method involves modeling 10 of a mining-influenced water body 15. Modeling 10 may include geochemical modeling, hydrological modeling, or both. The process continues to add alkaline materials to the water through alkaline addition 20, as needed. The alkaline materials are then mixed into the water body at mixing 30, which may include mixing, aeration, or a combination thereof. At measuring 40, parameters, including but not limited to pH, conductivity, oxidation-reduction potential, organic carbon, ionic concentrations in water, thickness, density, composition, or crystallography of sediments, are measured over time. Measurements may be taken at single points or as profiles. At reporting 50, the total carbon removed from the atmosphere is determined. One should note that the flowchart of the embodiment of FIG. 1A implies an order to the process, but no such limitation is intended, nor should any be implied. This applies to all flowchart and methods discussed herein.

[0036] In one embodiment, illustrated in FIG. 2, the measurements of parameters may be used to iteratively update the computer model between doses of alkaline materials, shown by path 60.

[0037] In one embodiment, the mining-influenced water body 15 may comprise a pit lake, an example of which is illustrated in FIG. 3, a tailings pond, or lined pit associated with a mine site. Mining-influenced water body 15 may also be one of flooded underground workings, tailings dams, sedimentation ponds, polishing ponds, sludge ponds, stratification ponds, and cooling ponds. Mining-influenced water bodies 15 may comprise ground water that becomes exposed due to the removal of earth during the mining or excavating process. The ground water then at least partially fills the void as shown.

[0038] In one embodiment, illustrated in FIG. 4, at least some of the water can be pumped into a separate system where dissolution of alkaline materials is accelerated, 12, before the solution of mine water and dissolved materials is returned to the main water body, 22. -8- Dissolution acceleration mechanisms may include one or more of mechanical milling, elevated temperature, lowering pH, raising pH, irradiation, or vibration. In other embodiments, contaminants released by the dissolution of alkaline materials are removed, 14, from the solution of mine water and dissolved materials before being returned to the main water body.

[0039] In one embodiment, illustrated in FIG. 4, the process may include some preparatory steps, including pre-screening 70, to determine suitability of the water body for carbon removal before work commences in the water body. Pre-screening 70 may include analysis of one or more of geology; bathymetry; climate; groundwater chemistry; surface water chemistry; stratification; water balance including inflows, outflows, precipitation, and evaporation; solute balance; microbiology; proximity to sources of alkaline materials; and presence of infrastructure such as roads, rail lines, power supplies, or electrical grid connections.

[0040] In one embodiment, modeling 10 may integrate weather forecasts 80 to guide timing, quantities, and / or type of alkaline material addition, as illustrated in FIG. 5. Weather forecast 80 may include weather parameters, including but not limited to temperature, wind speed, precipitation, barometric pressure, humidity, or a combination thereof. Weather parameters may affect the rate of absorption of CO2 by the water.

[0041] In one embodiment, the manner of aerating the water body may include forming droplets of water in the air over the water body via a sprayer, hose, showerhead, or fountain; forming bubbles of air in the water via a sparger, porous stone aerator, Venturi tube, aspirator, or pulverizing aerator; forced mixing via a mechanical mixer or pump; or by use of a gas-liquid contactor such as a column reactor, including falling film, bubble, packed, and plate styles. FIG. 6A illustrates a diagram of an example of a showerhead-style droplet generator, droplet generator 82, pumping water to create drops 84, which return to mining-influenced water body 15.

[0042] FIG. 6B illustrates a diagram of an example of aerator 86. Aerator 86 draws air into mining-influenced water body, 15, forming bubbles, 88.

[0043] In one embodiment, illustrated in FIG. 7, water with a partial pressure of carbon dioxide (pCCh) greater than 400 microatmospheres (patm) from mining-influenced water body 15 may be used to increase the rate and extent of alkaline mineral dissolution. This water may be at elevated pCO2 at depth due to, for example, influx of high pCO2 groundwater, decomposition of organic matter, respiration of aquatic organisms, thermal or chemical stratification of the lake, or seasonal ice cover. The water may be pumped to the surface, 18 and used for mineral dissolution in a vessel or used in situ by depositing alkaline mineral feedstocks into elevated pCO2 regions of the water body. In some embodiments, the elevated pCO2 water is used for carbonate mineralization as well as dissolution.

[0044] In some embodiments elevated pCO2 at depth is induced by deliberately importing or stimulating the growth of organic matter, 16 which undergoes aerobic degradation within the water body. Organic matter may be sunk to the bottom of the water body naturally or assisted using, as examples, application of sonic energy or densification such that density is greater than that of water. In some embodiments, alkaline material is co-deposited with organic matter and CO2 produced from the degradation of organic matter is captured in situ.

[0045] In one embodiment, illustrated in FIG. 8, the water may be pumped out of the water body into a reactor, via pumping 90, where alkaline materials may be added. The resulting solution may equilibrate with atmospheric CO2, via air contacting 100, by allowing contact with air. Measurements of key parameters are performed via measuring 110, then the solution is returned to the water body via returning 120. In one embodiment, precipitated sediments are harvested with harvesting 130 before returning the water to the water body. Precipitated -10- sediments may comprise sediment properties, including but not limited to thickness, density, composition, crystallography, or a combination thereof.

[0046] In one embodiment, illustrated in FIG. 9, acceleration process 140 to accelerate precipitation of carbonate minerals may be applied. Acceleration process 140 may comprise acceleration through change of temperature, pressure, pH, or introduction of nucleation sites.

[0047] In one embodiment, the alkaline material used may be one that increases the concentration of Ca2+, Mg2+, Na+, or K+ ions in the water. The alkaline material may be sourced from one or more of mafic rocks; ultramafic rocks; alkaline industrial wastes including ash, slag, tailings, waste rock, cement dust, lime kiln dust, or bauxite residues; oxides or hydroxides of calcium, magnesium, sodium, or potassium; or biogenic alkaline materials including biochar, torrefied plant matter, potash, or soda ash. In some embodiments, two or more of the aforementioned materials may be blended and added to the water body. In some embodiments, two or more of the aforementioned materials may be added in sequence.

[0048] In one embodiment, a sorbent material may be used to prevent the release of contaminants of concern by the alkaline materials or to remove contaminants of concern already present in the water body. One example is illustrated in FIG. 10 in which a single layer of precipitated minerals 150 settle to the bottom of a mining-influenced water body 15 followed by a single layer of sorbent 160. Sorbent 160 may be blended with alkaline materials or added to mining-influenced water body 15 following precipitation of carbonates. Sorbent 160 may include one or more of biochar; activated charcoal; torrefied plant matter; ash; unprocessed organic materials including manure, straw, pine needles, municipal solid waste, milk, wood chips, chicken litter, or sawdust; diatomaceous earth or diatomite; zeolites; clay; or a combination thereof.

[0049] In one embodiment, as illustrated in FIG. 11, alkaline minerals may be ground with mining-influenced water, 22, to accelerate dissolution and release of Ca2+, Mg2+, Na+, or K+ ions before being mixed into the water body, 30. In some embodiments independent of other embodiments shown in FIG. 11, the effluent is treated to remove contaminants, 24, such as dissolved metals before being mixed into the water body, 30. Treatment may include one or more of sorption, filtration, pH adjustment, electrochemical separation, or bioaccumulation. In some embodiments, potentially valuable contaminants such as dissolved metals are isolated from others of the contaminants, the water, a sorbent, filter, or bioaccumulator, 26, for reuse or sale.

[0050] One embodiment is a method comprised of modeling a mining-influenced water body, adding alkaline materials to the water body, mixing alkaline materials into the water body, measuring key parameters of the water body over time, and calculating total carbon removed from the atmosphere. Another embodiment comprises repeating the above method until the desired level of carbon is removed.

[0051] Another embodiment comprises the above method with an initial pre-screening of the mining-influenced water body for suitability for direct air capture of carbon. Another embodiment comprises the above method with an initial review of a weather forecast for the region of the mining-influenced water body.

[0052] One embodiment comprises a method that includes modeling a mining-influenced water body, pumping water out of the mining-influenced water body into a reactor, and adding alkaline materials into the reactor to form a solution. The process allows the solution to contact air to reach equilibrium with the air and then measures parameters, including the total carbon removed. The process then returns the solution to the water body. Another embodiment repeats the above method until the desired level of carbon is removed.

[0053] Another embodiment comprises the method above and includes harvesting and measuring carbon material precipitates in the solution prior to returning the solution to the water body. Another embodiment comprises the method above that harvests and measures precipitates and includes accelerating the precipitation of carbonate materials.

[0054] Industrial Applicability: The embodiments are further illustrated by the following non-limiting examples. Example 1

[0055] As an initial test of the application of these pure water concepts to the acidic, saline water found in pit lakes, geochemical simulation was conducted using open-source code. The initial solution composition was informed from water analysis data (e.g., pH and ion concentrations) of existing pit lakes and the incremental addition of one of CaO, Ca(OH)2, Mg(OH)2, NaOH, or CaSiCh was then simulated. At each simulation step the solution was allowed to equilibrate with atmospheric concentrations of CO2 and O2. In all cases CO2 entered the water and speciated to bicarbonate (HCO3) or carbonate (CO32). For Ca- and Mg-containing alkaline materials, most carbon was ultimately converted to carbonate minerals CaCOs or MgCCh. For NaOH, most carbon remained as dissolved carbonate due to the far higher solubility of sodium carbonates.

[0056] Fig. 11 illustrates predictions of pH and carbon removed beginning with an untreated pit lake with a pH of 3.21, and moderately high concentrations of sulfate and dissolved metals. The model predicted capture of 0.79 gCO2 / gCaO, where “g” indicates grams, and, following the initial neutralization, a constant equilibrium pH due to the buffering effect of calcite precipitation. Given the volume of this lake, 10-20 million metric tons (Mt)CO2 can be captured and permanently stored. Example 2

[0057] For a pure-water system in equilibrium with atmospheric CO2, carbonate equilibrium can be described by equations 1-4. First, dissolved [H2CO3*] can be defined as the sum of the concentrations of carbonic acid [H2CO3 (aq)] and dissolved CO2 [CO2 (aq)] (equation 1). Because the magnitude of [CO2 (aq)] was much greater than [H2CO3 (aq)], [H2CO3*] was essentially equal to [CO2 (aq)]. At equilibrium, the amount of dissolved CO2 in solution [H2CO3*] can be determined by Henry’s law (equation 2). H2CO3 was then speciated as HCO3' and CO32', according to equations 3 and 4. [H2CO*3] = [H2CO3(aq)] + [C02(aq)] ~ [C02(aq)]          (1) [H2CO3] = Kh X Pc02(atm)                           (2) H2CO*3 HCO3 + H+                              (3) HCO3 C0|" + H+                               (4) where Kh is the Henry’s law constant for CO2, IO'147 mol L'1 atm'1.

[0058] Purposeful addition of alkaline minerals, such as quicklime (Ca(OH)2), results in the conversion of carbonic acid to bicarbonate: 2H2CO3(aq) + Ca(OH)2 2HCO3 + 2H20 + Ca2+ (5) resulting in a reduction in the concentration of H2CO3 (3) and establishing a disequilibrium between Pco2 (aq) and Pco2 (atm) (equation 2). Equilibrium between the atmosphere and aqueous phase was re-established in the interfacial boundary layer of the solution by (2), and diffusive transport between the interfacial boundary layer and the solution follows, as described by Fick’s first law: J co 2 = D(CH2C0* — CH2Cq3)                            (6) where D is the mass transfer coefficient (e.g., cm s'1) across the air / water interface, Jis the CO2 flux across the air / water interface (e.g., mol cm'2 s'1), Ch2CO3* is the atmospherically equilibrated concentration at the air / water interface (e.g., mol cm'3), and Ch2CO3 is concentration of CO2 in solution after addition of alkaline materials. The actual rate of transfer depends on physical factors including wind speed and temperature.

[0059] The preceding examples can be repeated with similar success by substituting the generically or specifically described components and / or operating conditions of embodiments for those used in the preceding examples.

[0060] Optionally, the embodiments herein can include a general or specific purpose computer or distributed system programmed with computer software implementing steps described above, which computer software may be in any appropriate computer language, including but not limited to C, C++, FORTRAN, BASIC, PHREEQC, Java, Python, Linux, assembly language, microcode, distributed programming languages, etc. The apparatus may also include a plurality of such computers / distributed systems (e.g., connected over the Internet and / or one or more intranets) in a variety of hardware implementations. For example, data processing can be performed by an appropriately programmed microprocessor, computing cloud, Application Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA), or the like, in conjunction with appropriate memory, network, and bus elements. One or more processors and / or microcontrollers can operate via instructions of the computer code and the software is preferably stored on one or more tangible non-transitive memory-storage devices.

[0061] The terms, “a,” “an,” “the,” and “said” mean “one or more” unless context explicitly dictates otherwise.

[0062] Note that in the specification and claims, “about,” “approximately,” and / or “substantially” means within twenty percent (20%) of the amount, value, or condition given. All computer software disclosed herein may be embodied on any non-transitory computer-readable medium (including combinations of mediums), including without limitation CD-15- ROMs, DVD-ROMs, hard drives (local or network storage device), USB keys, other removable drives, ROM, and firmware.

[0063] Embodiments disclosed here can include every combination of features that are disclosed herein independently from each other. Although the embodiments have been described in detail with particular reference to the disclosed embodiments, other embodiments can achieve the same results. Variations and modifications will be obvious to those skilled in the art and this application is intended to cover, in the appended claims, all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference. Unless specifically stated as being “essential” above, none of the various components or the interrelationship thereof are essential to the operation of the embodiments. Rather, desirable results can be achieved by substituting various components and / or reconfiguring their relationships with one another.

Claims

1. A method of capturing carbon from an atmosphere, the method comprising:modeling a mining-influenced water body;contacting the mining-influenced water with an alkaline material to form a mining-influenced water and alkaline mixture;measuring a parameter of the mining-influenced water and alkaline mixture over time;measuring carbon content of the mining-influenced water and alkaline mixture; and calculating an amount of carbon captured from the atmosphere.

2. The method of claim 1 wherein modeling comprises geochemical modeling.

3. The method of claim 1 wherein modeling comprises hydrological modeling.

4. The method of claim 1 wherein modeling comprises integrating a weather forecast.

5. The method of claim 1 wherein the mining-influenced water body comprises a manmade pond.

6. The method of claim 1 wherein the mining-influenced water body comprises a pitlake.

7. The method of claim 1 wherein the mining-influenced water body comprises a linedpit.

8. The method of claim 1 further comprising aerating the mining-influenced water andalkaline mixture.

9. The method of claim 1 wherein the parameter comprises pH.

10. The method of claim 1 wherein the parameter comprises electrical conductivity ofwater.

11. The method of claim 1 wherein the parameter comprises oxidation-reductionpotential.

12. The method of claim 1 wherein the parameter comprises organic carbon.

13. The method of claim 1 wherein the parameter comprises ion concentration.

14. The method of claim 1 wherein the parameter comprises sediment properties.

15. The method of claim 1 further comprising pre-screening the mining-influenced waterbody.

16. The method of claim 1 further comprising contacting the mining-influenced water and alkaline mixture with organic matter.

17. The method of claim 1 further comprising dissolving the alkaline material into the mining-influenced water by a method comprising:disposing a portion of the mining-influenced water and alkaline mixture into a separate system;further dissolving the alkaline material in the mining-influenced water and alkaline mixture to form a mining-influenced water and alkaline solution in the separate system; andreturning the mining-influenced water and alkaline solution from the separate system to the mining-influenced water body.

18. The method of claim 17 wherein further dissolving the alkaline material comprises one or more of mechanical milling, elevating temperature of the mining-influenced water and alkaline mixture, lowering or raising pH of the mining-influenced water and alkaline mixture, irradiation, and vibration.

19. The method of claim 17, further comprising harvesting precipitated sediments from the solution prior to returning the solution to the mining-influenced water body.

20. The method of claim 17 wherein precipitation of sediments is accelerated prior to returning the mining-influenced water and alkaline solution to the mining-influenced water body.

21. The method of claim 17 further comprising disposing water from the mining-influenced water body which has a partial pressure of carbon dioxide over 400 microatmospheres into the separate system.

22. The method of claim 17 further comprising removing contaminants prior to returning the mining-influenced water and alkaline solution from the separate system to the mining-influenced water body.

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