Building materials from an aqueous solution

Abstract

A method of making building materials includes precipitating calcium salts from an aqueous solution by increasing a pH of the aqueous solution, and mixing the calcium salts with a first material including silicon to form a mixture. The mixture is then heated to form cement clinker.

What is claimed is: 
     
         1 . A method of making a building material comprising:
 precipitating calcium salts from an aqueous solution by increasing a pH of the aqueous solution;   mixing the calcium salts with a first material including silicon to form a mixture; and   heating the mixture to form cement clinker.   
     
     
         2 . The method of  claim 1 , further comprising mixing the calcium salts with at least one of a second material including aluminum or a third material including iron. 
     
     
         3 . The method of  claim 1 , wherein heating includes sintering at a temperature where tricalcium silicate is formed from the mixture. 
     
     
         4 . The method of  claim 1 , further comprising grinding the cement clinker to form cement, and wherein the mixture has a composition of Portland cement. 
     
     
         5 . The method of  claim 1 , wherein the aqueous solution is seawater and aqueous NaOH is added to the seawater to increase the pH of the aqueous solution and to precipitate the calcium salts. 
     
     
         6 . The method of  claim 5 , wherein the aqueous NaOH is supplied by an electrodialysis unit. 
     
     
         7 . A system for making building materials, comprising;
 an electrodialysis unit coupled to receive aqueous NaCl, and output aqueous HCl and aqueous NaOH;   a first precipitation unit including a first input and a second input, wherein the first input is coupled to receive an aqueous solution including dissolved ions and the second input is coupled to the electrodialysis unit to receive the aqueous NaOH, wherein in response to receiving the aqueous solution and the aqueous NaOH, the first precipitation unit precipitates calcium salts from the dissolved ions and outputs the aqueous solution; and   a first salt processing unit coupled to receive the calcium salts from the first precipitation unit and to convert the calcium salts into building materials.   
     
     
         8 . The system of  claim 7 , wherein the first salt processing unit is configured to receive a first material including silicon and heat the calcium salts and the first material to form cement clinker. 
     
     
         9 . The system of  claim 8 , wherein the first salt processing unit is configured to receive least one of a second material including aluminum or a third material including iron. 
     
     
         10 . The system of  claim 9 , further comprising a grinding unit to grind the cement clinker to form cement. 
     
     
         11 . The system of  claim 7 , wherein in response to receiving the aqueous NaOH the first precipitation unit precipitates magnesium salts in addition to the calcium salts. 
     
     
         12 . The system of  claim 7 , further comprising a second precipitation unit coupled to receive the aqueous solution from the first precipitation unit and the aqueous NaOH from the electrodialysis unit, wherein in response to receiving the aqueous solution and the aqueous NaOH, the second precipitation unit precipitates magnesium salts. 
     
     
         13 . The system of  claim 7 , wherein the first salt processing unit adds construction aggregate to the calcium salts. 
     
     
         14 . The system of  claim 7 , further comprising a desalination unit coupled to receive the aqueous solution from the first precipitation unit, wherein the desalination unit outputs fresh water.