Composite materials, methods of production and uses thereof
The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.
1. An article of manufacture comprising a composite material distributed as a plurality of discrete concrete objects; wherein one or more ducts or channels are arranged between or through the plurality of discrete concrete objects to form a fluid transport system within the one or more ducts or channels and/or with an exterior of the plurality of discrete objects, wherein the composite material comprises:
a plurality of bonding elements, wherein, each bonding element comprises:
a core comprising primarily calcium silicate,
a silica-rich first or inner layer, and
a calcium carbonate-rich second or outer layer; and
filler particles comprising coarse filler particles and/or fine filler particles, wherein the plurality of bonding elements and the plurality of filler particles together form one or more bonding matrices and the bonding elements and the filler particles are substantially evenly dispersed therein and bonded together.
2. The article of claim 1 , wherein the plurality of discrete concrete objects are arranged within an envelope or chamber.
3. The article of claim 1 , wherein each of the plurality of discrete concrete objects comprises one or more reinforcement elements embedded therein.
4. The article of claim 3 , wherein the one or more reinforcement elements are selected from bars, wires and cables.
5. The article of claim 4 , wherein the one or more reinforcement bars are made of iron, steel, polymeric materials, glass, or a combination thereof.
6. The article of claim 1 , wherein the plurality of discrete concrete objects do not have reinforcement elements embedded therein.
7. The article of claim 1 , wherein the plurality of bonding elements are chemically transformed from a ground calcium silicate composition, comprising one or more of natural or synthetic wollastonite, pseudo-wollastonite, rankinite, gehlenite, belite, alite and amorphous phase.
8. The article of claim 1 , wherein the plurality of bonding elements are prepared by a chemical transformation from ground calcium silicate by reacting it with CO2 via a controlled hydrothermal liquid phase sintering process.
9. The article of claim 1 , wherein the plurality of bonding elements are chemically transformed from a precursor calcium silicate other than synthetic wollastonite or pseudo-wollastonite.
10. The article of claim 1 , wherein the weight ratio of bonding elements: filler particles is about 1:5.
11. The article of claim 1 , having water absorption of less than about 10%.
12. The article of claim 1 , wherein the fluid transport system is adapted to flowing a gas through the one or more ducts or channels and the exterior of the plurality of discrete objects.
13. The article of claim 12 , wherein the gas comprises carbon dioxide.
14. The article of claim 12 , wherein the fluid that flows through the one or more ducts or channels and the exterior of the plurality of discrete objects changes it direction at least once.
15. The article of claim 12 , wherein the fluid that flows through the one or more ducts or channels and the exterior of the plurality of discrete objects changes it velocity at least once.
16. The article of claim 1 , wherein the fluid transport system within the exterior of the plurality of discrete objects comprises of a flow between the envelope or chamber or a chamber component within the envelope or chamber.
17. A process for producing an article of manufacture, comprising:
mixing a particulate composition and a liquid composition to form a mixture;
casting or extruding or otherwise forming the mixture in a mold to generate a casted or extruded or otherwise formed green body comprising a plurality of discrete concrete objects; wherein,
one or more ducts or channels are arranged between or through the plurality of discrete concrete objects and an exterior of the plurality of discrete objects;
maintaining an atmosphere of CO 2 and/or water vapor in the one or more interior ducts or channels and the exterior of the plurality of discrete objects; and
curing the plurality of discrete objects at a temperature in the range from about 20° C. to about 150° C. for about 1 hour to about 80 hours under an atmosphere of water and/or CO2 having a pressure in the range from ambient atmospheric pressure to about 60 psi above ambient and having a CO 2 concentration ranging from about 10% to about 90%.
18. The process of claim 17 , wherein maintaining an atmosphere of CO2 and/or water vapor in the one or more interior ducts or channels and/or the exterior of the plurality of discrete objects comprises:
containing the atmosphere within the one or more interior channels and/or the exterior of the plurality of discrete objects;
circulating the contained atmosphere of CO2 and/or water vapor;
removing or adding water vapor to or from the contained atmosphere; and
heating the contained atmosphere.