Hydraulic cements comprising carbonate compound compositions
Hydraulic cement compositions that include a carbonate compound composition, e.g., a salt-water derived carbonate compound composition containing crystalline and/or amorphous carbonate compounds, are provided. Also provided are methods of making and using the hydraulic cements, as well as settable compositions, such as concretes and mortars, prepared therefrom. The cements and compositions produced therefrom find use in a variety of applications, including use in a variety of building materials and building applications.
1. A method, comprising: subjecting alkaline earth metal ion containing water comprising carbonate and/or bicarbonate ions to carbonate compound precipitation conditions adapted to produce a precipitated carbonate compound composition comprising greater than 50% carbonate compound which after combination with water, setting and hardening has a compressive strength in a range of 20-70 MPa wherein the carbonate compound precipitation conditions favor precipitation of one or more metastable carbonate compounds selected from the group consisting of aragonite, vaterite, amorphous calcium carbonate, and mixtures thereof and wherein the carbonate compound composition is a hydraulic cement composition.
2. The method of claim 1 , wherein the method further comprises separating the precipitated carbonate compound composition from a mother liquor.
3. The method of claim 2 , wherein the step of separating comprises filtration of the precipitated carbonate compound composition to produce a filtrate.
4. The method of claim 2 , wherein the method further comprises drying the precipitated carbonate compound composition to produce a dried carbonate compound composition.
5. The method of claim 4 , wherein the drying comprises spray drying.
6. The method of claim 5 , wherein the drying results in a dry particulate powder composition.
7. The method of claim 1 , wherein the precipitated carbonate compound composition is a cement composition.
8. The method of claim 1 , wherein the alkaline earth metal ion containing water is seawater or brine.
9. The method of claim 8 , wherein the seawater or brine comprises strontium in an amount ranging from 3 to 10,000 ppm.
10. The method of claim 1 , wherein the alkaline earth metal ion containing water comprises calcium in an amount ranging from 50 to 20,000 ppm.
11. The method of claim 1 , wherein the carbonate compound precipitation conditions comprise a temperature ranging from 5 to 70° C.
12. The method of claim 1 , wherein the carbonate compound precipitation conditions comprise a pH ranging from 5 to 14.
13. The method of claim 1 , wherein the carbonate compound precipitation conditions comprise addition of a pH raising agent.
14. The method of claim 13 , wherein the pH raising agent is a hydroxide.
15. The method of claim 1 , wherein the precipitated carbonate compound composition has a particle size ranging from 0.1 micron to 100 micron.
16. The method of claim 1 , wherein the precipitated carbonate compound composition comprises elements selected from the group consisting of sodium, magnesium, silicon, sulfur, potassium, calcium, strontium, and mixture thereof.
17. The method of claim 1 , wherein the precipitated carbonate compound composition after combination with Portland cement and water, setting, and hardening has a compressive strength in a range of 20-70 MPa.
18. The method of claim 1 , wherein the method further comprises combining the precipitated carbonate compound composition with Portland cement, aggregate, or combination thereof to produce a concrete composition.