Carbon sequestration by proppants

Abstract

Method of carbon sequestration by capturing CO.sub.2 emissions and making a proppant from the captured carbon in either a carbon mineralization process or in a carbon nanomaterial manufacturing process, followed by treatments to ensure the quality control of the proppants so that they are suitable for use in hydraulic and other reservoir fracturing methods. Injection of the manufactured proppant in fracking thus sequesters the carbon from the original captured CO.sub.2 in the reservoir.

Claims

1. A method of sequestering carbon and producing hydrocarbon from an underground formation having at least one well, comprising the method steps of: a) making a proppant by: i) capturing CO.sub.2 from a gas or liquid; ii) reacting said CO.sub.2 with magnesium or calcium ions in a carbon mineralization reaction under alkaline pH to make porous particles of magnesium carbonate or calcium carbonate, wherein said particles have: (1) a crushing rate of less than 10% at 28 MPa, (2) a bulk density of 1.5-2.5 g/cm.sup.3, (3) a size of 0.1-2 mm, and (4) a porosity of 30-50%; iii) size sorting said particles to produce size ranges of between 20 mesh and 40 mesh, said size sorted particles being a proppant; b) introducing a first fractured fluid (FF) through said at least well into the underground formation at a pressure greater than a minimum in-situ rock stress for formation of fractures (FR) in the underground formation; c) introducing a second FF containing said proppant through said at least one well into the underground formation to prop open said FR and thereby sequestering carbon from said CO.sub.2 in said underground formation; and d) producing hydrocarbon from said at least one well.

2. The method of claim 1 said particles further having a roundedness of at least 0.7 and a sphericity of at least 0.7.

3. The method of claim 1 further comprising coating said particles with a resin.

4. The method of claim 1 further comprising coating said particles with a thermoplastic polymer or an adhesive polymer.

5. The method of claim 1 further comprising combining said proppant with magnetic particles.

6. The method of claim 1 further comprising combining said proppant with fibers.

7. The method of claim 1 said particles having a crushing rate of <9% at 28 MPa.

8. The method of claim 1 where said particles are agglomerated to produce sizes larger than 100 nm.

9. The method of claim 1 where said particles are agglomerated and coated to produce sizes larger than 100 nm.

10. The method of claim 1 where CO2 is captured from a flue gas stream and said magnesium or calcium ions are from recycled cement, brine or mining tailings.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 Schematic of hydraulic fracturing of a natural gas reservoir.

(2) FIG. 2 Sphericity and roundness.

(3) FIG. 3 Exemplary sand and ceramic proppants.

(4) FIG. 4 Blue Planet carbon capture and mineralization process.

(5) FIG. 5 Bergen Carbon Solutions carbon capture and manufacture of CNM process.

(6) FIG. 6 Closeup of reactor in FIG. 5.

DETAILED DESCRIPTION

(7) The disclosure provides a novel proppant, method of making same, and methods of using same in hydraulic and other types of fracturing of oil, gas, and water wells.

(8) The examples herein are intended to be illustrative only, and not unduly limit the scope of the appended claims.

Carbon Mineralization

(9) In one embodiment, particulates are made by contacting a gaseous source of CO.sub.2 (such as flue gas or CO.sub.2 from a direct air capture (DAC) system) and an aqueous capture ammonia to produce a solid carbonate product and an aqueous ammonium salt, and then contacting the aqueous ammonium salt liquid with a geomass, e.g., alkaline waste product such as recycled cement, to regenerate the aqueous capture ammonia.

(10) In some embodiments, combination of the CO.sub.2 capture liquid and gaseous source of CO.sub.2 results in production of an aqueous carbonate, which aqueous carbonate is then subsequently contacted with a divalent cation source, e.g., a Ca.sup.2+ and/or Mg.sup.2+ source, to produce the CO.sub.2 sequestering material. In yet other embodiments, a one-step CO.sub.2 gas absorption carbonate precipitation protocol is employed.

(11) Any convenient cation source may be employed in such instances. Cation sources of interest include, but are not limited to, the brine from water processing facilities such as sea water desalination plants, brackish water desalination plants, groundwater recovery facilities, wastewater facilities, blowdown water from facilities with cooling towers, produced water and the like, which produce a concentrated stream of solution high in cation content. Also of interest as cation sources are naturally occurring sources, such as but not limited to native seawater and geological brines. In some instances, the cation source may be a waste product of another step of the process, e.g., a calcium salt (such as CaCl.sub.2) produced during regeneration of ammonia from the aqueous ammonium salt.

(12) In yet other embodiments, the aqueous capture ammonia includes cations, e.g., as described above. The cations may be provided in the aqueous capture ammonia using any convenient protocol. In some instances, the cations present in the aqueous capture ammonia are derived from a geomass used in regeneration of the aqueous capture ammonia from an aqueous ammonium salt. In addition, and/or alternatively, the cations may be provided by combining an aqueous capture ammonia with a cation source, e.g., as described above.

(13) The gaseous source of CO.sub.2 can be waste streams produced by industrial plants that combust fossil fuels, e.g., coal, oil, natural gas, as well as man-made fuel products of naturally occurring organic fuel deposits, such as but not limited to tar sands, heavy oil, oil shale, etc. In certain embodiments, power plants are pulverized coal power plants, supercritical coal power plants, mass burn coal power plants, fluidized bed coal power plants, gas or oil-fired boiler and steam turbine power plants, gas or oil-fired boiler simple cycle gas turbine power plants, and gas or oil-fired boiler combined cycle gas turbine power plants. Direct capture from air may also be used.

(14) Geomass can be mine tailings, mining dust, sand, baghouse fines, soil dust, dust, cement kiln dust, slag, steel slag, iron slag, boiler slag, coal combustion residue, ash, fly ash, slurry, lime slurry, lime, kiln dust, kiln fines, residue, bauxite residue, demolished concrete, returned concrete, crushed concrete, recycled concrete, recycled mortar, recycled cement, demolished building materials, recycled building materials, recycled aggregate, etc.

Carbon Nanomaterials

(15) Carbon dioxide is electrochemically decomposed to carbon and oxygen gas in molten LiCl-5.0 wt. % Li.sub.2O molten salts at 903 K (629.8° C.) using a titanium cathode and inert platinum anode (Li 2016). CO.sub.2 chemically dissolves into the LiCl—Li.sub.2O melt by reacting with Li.sub.2O, changing the electrolyte LiCl—Li.sub.2O—CO.sub.2 into Li.sub.2CO.sub.3 and LiCl. Carbonate anions are electrochemically reduced to carbon on the cathode, while oxygen complexes of carbonate anions are oxidized at the anode, generating O.sub.2. Electrolysis of the LiCl-5.0 wt. % Li.sub.2O molten salt under a CO.sub.2 atmosphere at 0.05 A/cm.sup.2 in Li (2015) yielded anodic gas with a CO.sub.2/O.sub.2 ratio of 0.42. The CO.sub.2/O.sub.2 ratio increased with increasing current density.

(16) CO.sub.2 can also be dissolved into carbonates and electrochemically split to produce CNM. Carbon deposition in CaCO.sub.3, SrCO.sub.3 and BaCO.sub.3 dissolved electrolyte occurs and carbon products aggregate on the cathodic surface, and then collected. Li (2018) demonstrated that the alkaline earth carbonate additives sustained continuous CO.sub.2 electrolysis and carbon electro-deposition. However, the micromorphology and microstructure of the carbon deposits were found to be significantly changed mainly because of the interface modification induced by the alkaline earth carbonate additives. However, such changes may not present problems for proppant use, plus higher yields may be obtained by optimizing the electrolytic conditions. Compared to pure Li.sub.2CO.sub.3, alkaline earth carbonate additives provide the carbon nanotubes with a thicker diameter and more prominent hollow structure.

Tables

(17) TABLE-US-00002 TABLE 1 Properties of 20/40 ceramic proppants and sands. Type of proppants Ceramic Sand Mesh range (mesh) 20/40 20/40 Bulk density (g/cm.sup.3) 1.58 1.59 Apparent density (g/cm.sup.3) 2.84 2.63 Average diameter (μm) 617 658.3 Turbidity (FTU) 14 37 Roundness (dimensionless) 0.8 0.7 Sphericity (dimensionless) 0.8 0.7 Acid-solubility (%) 6.9 7 Crushing rate (%) 5 (effective 9 (effective closure stress = closure stress = 52 MPa) 28 MPa)

(18) TABLE-US-00003 TABLE 2 Frack Fluids Base Fluid Fluid Type Main Composition Water based Slickwater Water + sand (+chemical additives which may include surfactant, friction reducer, scale inhibitor, and biocide) Linear fluids Gelled water, GUAR < HPG, HEC, CMHPG Cross-linked fluid Crosslinker + GUAR, HPG, CMHPG, CMHEC Viscoelastic surfactant Electrolite + surfactant gel fluids Foam based Water based foam Water and Foamer + N.sub.2 or CO.sub.2 Acid based foam Acid and Foamer + N.sub.2 Alcohol based foam Methanol and Foamer + N.sub.2 Oil based Linear fluids Oil, Gelled Oil Cross-linked fluid Phosphate Ester Gels Water Emulsion Water + Oil + Emulsifiers Acid based Linear — Cross-linked — Oil Emulsion — Alcohol based Methanol/water mixes Methanol + water or 100% methanol Emulsion based Water-oil emulsions Water + Oil CO.sub.2-methanol CO.sub.2 + water + methanol Others — Other fluids Liquid CO.sub.2— CO.sub.2 Liquid nitrogen N.sub.2 Liquid helium He Liquid natural gas LPG (butane and/or propane)

(19) The following references are incorporated by reference in their entirety for all purposes. Czaplicka, N. Utilization of gaseous carbon dioxide and industrial Ca-rich waste for calcium carbonate precipitation, Energies, 13: 6239 (2020). Li, L., et al. Electrochemical conversion of CO.sub.2 to carbon and oxygen in LiCl—Li.sub.2O melts, Electrochimica Acta 190:655-658 (2015). Li, Z., et al. Carbon dioxide electrolysis and carbon deposition in alkaline-earth-carbonate-included molten salts electrolyzer, New Journal of Chemistry 42(19) (2018). Liu, M.; Greeshma Gadikota, G. Integrated CO.sub.2 capture, conversion, and storage to produce calcium carbonate using an amine looping strategy, Energy Fuels 33, 3, 1722-1733 (2019). U.S. Ser. No. 10/343,199 Production of secondary aggregates. U.S. Ser. No. 10/960,350 Ammonia mediated carbon dioxide (CO.sub.2) sequestration methods and systems. US20060039853 Separation of carbon dioxide (CO.sub.2) from gas mixtures by calcium based reaction separation (CaRS—CO.sub.2) process. US2019119158 Improved production of aggregates. US2020370001 Carbon sequestration methods and systems, and compositions produced thereby. US2021069669 Continuous carbon sequestration material production methods and systems for practicing the same. U.S. Pat. No. 7,753,618 Rocks and aggregate, and methods of making and using the same. U.S. Pat. No. 8,470,282 Production of calcium carbonate. U.S. Pat. No. 9,266,057 Process or separating and enriching carbon dioxide from atmospheric gases in air or from atmospheric gases dissolved in natural water in equilibrium with air. U.S. Pat. No. 9,707,513 Alkali enrichment mediated CO.sub.2 sequestration methods, and systems for practicing the same. WO2019231334 Apparatus and method for purification of carbon nanomaterial.