INTEGRATED CHEMICAL PROCESS

• US 20090305378A1
• Filed: 11/21/2007
• Published: 12/10/2009
• Est. Priority Date: 11/22/2006
• Status: Active Grant

• Current Assignee: Mineral Carbonation International Pty., Ltd.
• Original Assignee: Orica Explosives Technology Pty Limited (Orica Limited)
• Inventors: Brent, Geoffrey Frederick
• Granted Patent: US 9,566,550 B2
• Time in Patent Office: Days
• US Class Current: 435/168
• CPC Class Codes: B01D 2251/402 of magnesium
• CPC Class Codes: B01D 2251/404 of calcium
• CPC Class Codes: B01D 2251/606 Carbonates
• CPC Class Codes: B01D 2255/00 Catalysts
• CPC Class Codes: B01D 2255/804 Enzymatic
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2258/0233 from cement factories
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 2259/80 Employing electric, magnetic, electromagnetic or wave energy, or particle radiation
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01D 53/80 Semi-solid phase processes, i.e. by using slurries
• CPC Class Codes: B01D 53/8671 Removing components of defined structure not provided for in B01D53/8603 - B01D53/8668
• CPC Class Codes: C01B 32/60 Preparation of carbonates or bicarbonates in general of percarbonates C01B15/10; of specific carbonates or bicarbonates according to the cation C01B-C01G
• CPC Class Codes: C01D 7/00 Carbonates of sodium, potassium or alkali metals in general
• CPC Class Codes: C01F 11/18 Carbonates
• CPC Class Codes: C01F 5/24 Magnesium carbonates
• CPC Class Codes: C04B 7/367 Avoiding or minimising carbon dioxide emissions
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/129 Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2
• CPC Class Codes: Y02P 40/18 : Carbon capture and storage [CCS]

Abstract

A mineral carbonation process, characterised in that the silicate feedstock is thermally activated by using heat generated from the combustion of fuel prior to reacting the activated slurry feedstock with carbon dioxide.

Claims

1. A process for the solidification of carbon dioxide of by reaction of carbon dioxide with an alkali metal or alkaline earth metal silicate feedstock to form a corresponding alkali metal or alkaline earth metal carbonate, which process comprises direct thermal activation of the alkali metal or alkaline earth metal silicate feedstock by combustion of fuel to produce an activated feedstock, suspending the activated feedstock in a solvent slurry and contacting the activated feedstock with carbon dioxide to convert the carbon dioxide to form an alkali metal or alkaline earth metal carbonate.

2. A process according to claim 1, wherein direct thermal activation of the alkali metal or alkaline earth metal silicate feedstock by combustion of fuel occurs in a furnace, kiln or similar combustion chamber or heating vessel.

3. A process according to claim 1, wherein the alkali metal or alkaline earth metal feedstock is preheated prior to direct thermal activation by combustion of the fuel using heat liberated from the reaction of carbon dioxide with the activated feedstock and/or low grade or waste heat drawn from an associated carbonaceous or hydrocarbonaceous fuel combustion, gasification or reforming process.

4. A process according to claim 1, wherein direct thermal activation of the feedstock takes place by raising and maintaining the temperature of said feedstock to a temperature of from about 580 and 800 degrees Celsius.

5. A process according to claim 1, wherein the feedstock is heated in a heating vessel that is designed to rotate and/or agitate the feedstock during heating thereof to assist in dehydroxylation and activation.

6. A process according to claim 1, wherein feedstock is heated in a heating vessel of a vertical shaft design comprising one or more substantially vertical chambers and wherein the feedstock is charged and flows counter-currently to gases produced by the combustion of the fuel.

7. A process according to claim 1, wherein the feedstock is heated in isolation from the combustion gases of the fuel via radiation, conduction or convection from the fuel combustion chamber in a suitably designed heating vessel.

8. A process according to claim 2, wherein the alkali or alkaline earth metal silicate feedstock is transported in pipes or vessels through the heating vessel in fluid media, such fluids being either gases or liquids.

9. A process according to claim 1, wherein the feedstock is subjected to comminution to reduce the feedstock average particle size to less than about 200 microns.

10. A process according to claim 1, wherein the activated feedstock is suspended in a weakly acidic aqueous or mixed aqueous and/or saline or other solvent miscible with carbon dioxide before and/or after the direct thermal activation.

11. A process according to claim 10, where the solvent is chosen from any one or more of water, weak acids for example acetic acid, oxalic acid, ascorbic acid, phthalic acid, orthophosphoric acid, citric acid, formic acid or salt solutions of such weak acids, saline solutions, aqueous saline and sodium bicarbonate solutions, potassium bicarbonate solutions, mixed aqueous and alcohol solutions such as aqueous ethanol or methanol solutions, mixed aqueous and glycol solutions, mixed aqueous and glycerol solutions.

12. A process according to claim 1, wherein the activated feedstock is mixed with an aqueous solvent stream containing a weak acid and subjected to further comminution after the direct thermal activation step in a wet-milling process to a particle size of less than 75 microns.

13. A process according to claim 1, wherein the activated feedstock is contacted with supercritical, liquefied or high-pressure gaseous carbon dioxide to substantially convert the carbon dioxide to alkali metal or alkaline earth metal carbonates.

14. A process according to claim 1, where the carbon dioxide and activated feedstock are contacted in a reaction vessel that is designed to provide highly turbulent or rapidly dispersive or attritive conditions to rapidly and substantially convert the carbon dioxide to alkali metal or alkaline earth metal carbonates.

15. A process according to claim 1, wherein the carbon dioxide is derived from emissions from a carbonaceous fuel combustion process, hydrocarbonaceous fuel combustion process, or hydrocarbon gasification process or reforming processes.

16. A process according to claim 15, wherein the carbon dioxide is derived from flue emissions from coal, oil or natural gas-fired electricity generation.

17. A process according to claim 1, wherein the carbon dioxide gas is derived from an ammonia manufacturing plant.

18. A process according to claim 1, wherein the carbon dioxide gas is derived from a Portland cement manufacturing plant.

19. A process according to claim 1, wherein the carbon dioxide is derived from the oxidation of least 20% of fuel derived from renewable biomass.

20. A process according to claim 1, wherein the fuel comprises at least 20% of fuel derived from renewable biomass.

21. A process according to claim 1, wherein the alkali metal or alkaline earth metal feedstock comprises serpentine or a polymorph thereof, antigorite, lizardite or chrysotile, olivine forsterite, brucite, dunite, peridotite, wollastonite, talc, harzburgite, or a mixture of any two or more thereof.

22. A process according to claim 1, wherein the combustion of the fuel is achieved with the addition of oxygen-enriched streams to generate carbon dioxide and water vapour for ease of subsequent solidification into carbonates.

23. A process according to claim 1, wherein the alkali metal or alkaline earth metal feedstocks are crushed in crushers and ground in mills in comminution circuits that draw electrical energy produced from an associated electricity generation plant.

24. A process according to claim 1, wherein the carbon dioxide is in dilute streams or is drawn directly from the atmosphere.

25. A process according to claim 24, wherein the carbon dioxide is contacted with the activated feedstock in systems of open fields, slurry dams, stockpiles or similar aerated structures or heap leach arrangements containing the activated feedstock.

26. A process according to claim 25, wherein sprays, atomizers or channels are used to distribute aqueous streams through the systems of open fields, slurry dams, stockpiles or similar aerated structures or heap leach arrangements containing the activated feedstock.

27. A process according to claim 26, wherein carbonates produced by reaction of the carbon dioxide and activated feedstock are periodically removed from the systems.

28. A process according to claim 26, wherein an enzyme catalyst is added to the aqueous streams to accelerate the formation of carbonic acid.