Rocks and Aggregate, and Methods of Making and Using the Same

• US 20100144521A1
• Filed: 02/01/2010
• Published: 06/10/2010
• Est. Priority Date: 05/29/2008
• Status: Abandoned Application

• Current Assignee: Calera Corporation
• Original Assignee: Calera Corporation
• Inventors: Patterson, Joshua, Farsad, Kasra, Thatcher, Ryan, Constantz, Brent, O'Neil, James, Youngs, Andrew, Camire, Chris, Stagnaro, John
• Application Number:
  US12/698,043
• Publication Number:
  US 20100144521A1
• Time in Patent Office: Days
• US Class Current: 502/400
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01J 20/043 Carbonates or bicarbonates, e.g. limestone, dolomite, aragonite
• CPC Class Codes: B01J 20/2803 Sorbents comprising a binder, e.g. for forming aggregated, agglomerated or granulated products
• 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: C01F 11/181 Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by control of the carbonation conditions
• CPC Class Codes: C01F 5/24 Magnesium carbonates
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2002/82 by IR- or Raman-data
• CPC Class Codes: C01P 2002/88 by thermal analysis data, e.g. TGA, DTA, DSC
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2006/11 Powder tap density
• CPC Class Codes: C04B 14/26 Carbonates
• CPC Class Codes: C04B 14/28 of calcium
• CPC Class Codes: C04B 18/02 Agglomerated materials , e.g. artificial aggregates
• CPC Class Codes: C04B 2103/0043 Compounds chosen for their specific Moh's hardness
• CPC Class Codes: C04B 2103/0086 Chelating or complexing agents
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

Compositions comprising synthetic rock, e.g., aggregate, and methods of producing and using them are provided. The rock, e.g., aggregate, contains CO₂ and/or other components of an industrial waste stream. The CO₂ may be in the form of divalent cation carbonates, e.g., magnesium and calcium carbonates. Aspects of the invention include contacting a CO₂ containing gaseous stream with a water to dissolve CO₂, and placing the water under precipitation conditions sufficient to produce a carbonate containing precipitate product, e.g., a divalent cation carbonate.

Claims

1. An aggregate comprising a synthetic CO₂-sequestering component wherein the aggregate has a Mohs hardness of 3 or greater.

2. The aggregate of claim 1, wherein the CO₂-sequestering component comprises one or more carbonate compounds.

3. The aggregate of claim 2, wherein the one or more carbonate compounds make up at least 50% w/w of the aggregate;

or at least 90% w/w of the aggregate;

or at least 98% w/w of the aggregate.

4. The aggregate of claim 2, wherein the carbonate compounds comprise magnesium carbonate, calcium carbonate, magnesium calcium carbonate, or a combination thereof.

5. The aggregate of claim 4, wherein the molar ratio of calcium to magnesium in the aggregate is (i) from 1/1 Ca/Mg to 1/10 Ca/Mg, or (ii) from 150/1 Ca/Mg to 10/1 Ca/Mg, or (iii) from 2/1 Ca/Mg to 1/2 Ca/Mg.

6. The aggregate of claim 1 having carbon isotopic fractionation (δ

¹³C) value more negative than −

10%, optionally more negative than −

20%.

7. The aggregate of claim 1 that has a bulk density of between 75 lb/ft³ and 125 lb/ft³, or between 90 lb/ft³ and 115 lb/ft³.

8. The aggregate of claim 2, also comprising a sulfate and/or a sulfite, wherein the combined sulfate and/or sulfite comprise at least 0.1% w/w of the aggregate.

9. A structure comprising the aggregate of claim 1, wherein the structure is a building, a roadway, or a dam.

10. The structure of claim 9, that is a roadway, wherein the roadway sequesters at least 1 ton of CO₂ per lane mile of roadway, and wherein the roadway sequesters at least 100 tons of CO₂ per lane mile of roadway, or wherein the roadway sequesters at least 1000 tons of CO₂ per lane mile of roadway.

11. A method of producing aggregate comprising:

(i) precipitating a CO₂-sequestering carbonate compound composition from a divalent cation-containing water to form a precipitate; and

(ii) processing the CO₂-sequestering carbonate compound composition under conditions that produce aggregate with a Mohs hardness of at least 3 Mohs.

12. The method of claim 11, wherein producing the aggregate comprises;

either

(i) subjecting the precipitate of claim 11 to elevated temperature, elevated pressure, or a combination thereof, optionally wherein said elevated temperature, elevated pressure, or combination thereof is produced by an extruder;

or

(ii) subjecting the precipitate of claim 11 to exposure to the open environment and mechanically processing, optionally wherein mechanically processing comprises compression applied with a steel roller or a press;

or

(iii) producing aggregate of a predetermined size and shape.

13. The method of claim 11, further comprising contacting the divalent cation-containing water with CO₂ from an industrial waste gas stream, optionally wherein the industrial waste gas stream is a flue gas from a power plant or a cement plant, and wherein the power plant is a coal-fired power plant.

14. The method of claim 11, further comprising contacting the divalent cation-containing water with CO₂ from the combustion of a fossil fuel, wherein the fossil fuel comprises natural gas or coal, and wherein the fossil fuel comprises coal.

15. The method of claim 11, wherein the divalent cation-containing water comprises divalent cations from a saltwater, wherein the saltwater comprises seawater or brine.

16. The method of claim 11, wherein the processing of the precipitate comprises either;

(i) combining the precipitate with a cementitous material and water, and allowing the combination to set to provide a solidified material;

or

(ii) mechanically spreading the precipitate, irrigating the spread precipitate, and compacting the spread precipitate until a desired depth and desired chemical and mechanical properties are obtained;

and further comprising breaking up the solidified material.