Compositions and methods for converting hazardous waste glass into non-hazardous products

Abstract

The present invention provides compositions and methods for converting hazardous waste glass into safe and usable material. In particular, the present invention provides compositions and methods for producing ceramic products from toxic-metal-containing waste glass, thereby safely encapsulating the metals and other hazardous components within the ceramic products.

1 . A method of producing a ceramic article from hazardous waste glass comprising:
 a) mixing hazardous waste glass with a filler and a non-aqueous binder;   b) pressing the mixture to produce a green article; and   c) firing said green article to produce a ceramic article.   
     
     
         2 . The method of  claim 1 , wherein said hazardous waste glass comprises one or more of the following characteristics: greater than 1% lead, greater than 5% lead, greater than 20% lead, CRT glass, fluorescent light glass, greater than 1% barium, greater than 5% barium, and greater than 20% barium. 
     
     
         3 . The method of  claim 2 , wherein said filler is selected from the group consisting of alumina, magnesium silicate, and bentonite. 
     
     
         4 . The method of  claim 1 , wherein said non-aqueous binder is selected from the group consisting polyvinyl alcohol and sodium silicate. 
     
     
         5 . The method of  claim 1 , wherein pressing is selected from the group consisting of dry pressing, placing the mixture under pressure of at least 200 kg/cm 2 , and placing the mixture under pressure of about 400 kg/cm 2 . 
     
     
         6 . The method of  claim 1 , wherein said firing is selected from the group consisting of heating said green article to at least 500° C., heating said green article to a temperature less than 1000° C., heating said green article to at least 650° C., heating said green article to a temperature less than 815° C. 
     
     
         7 . The method of  claim 1 , wherein said ceramic article comprises one or more of the following characteristics: safely encapsulates the hazardous components of said hazardous waste glass, meets EPA standards for toxicity and leaching of said toxic and/or heavy metals, exhibits lead leachate concentrations of less than 5 ppm, exhibits barium leachate concentrations of less than 100 ppm, and exhibits barium leachate concentrations of less than 10 ppm. 
     
     
         8 . A method of producing a ceramic article from hazardous waste glass comprising:
 a) mixing hazardous waste glass with a filler and a plastic material;   b) mixing the hazardous waste glass, filler, and plastic material mixture with a non-aqueous binder to produce a batch mixture;   c) pressing said batch mixture to produce a green article;   d) drying the green article; and   e) firing the green article to produce a ceramic article.   
     
     
         9 . The method of  claim 8 , wherein said hazardous waste glass comprises one or more of the following characteristics: greater than 1% lead, greater than 5% lead, greater than 20% lead, CRT glass, fluorescent light glass, greater than 1% barium, greater than 5% barium, and greater than 20% barium. 
     
     
         10 . The method of  claim 8 ,
 wherein said filler is selected from the group consisting of alumina, magnesium silicate, and bentonite,   wherein said plastic material comprises clay, and   wherein said non-aqueous binder is selected from the group consisting polyvinyl alcohol and sodium silicate.   
     
     
         11 . The method of  claim 8 , wherein mixing said hazardous waste glass with said filler and said plastic material comprises wet stirring followed by drying. 
     
     
         12 . The method of  claim 8 , wherein pressing is selected from the group consisting of dry pressing, placing the mixture under pressure of at least 200 kg/cm 2 , and placing the mixture under pressure of about 400 kg/cm 2 . 
     
     
         13 . The method of  claim 8 , wherein said firing is selected from the group consisting of heating said green article to at least 500° C., heating said green article to a temperature less than 1400° C., heating said green article to at least 650° C., heating said green article to a temperature less than 1250° C. 
     
     
         14 . The method of  claim 8 ,
 further comprising a step between steps (a) and (b) of sieving said batch mixture through a first mesh, wherein said first mesh comprises a 50-150 mesh;   further comprising a step between steps (b) and (c) of sieving said batch mixture through a second mesh, wherein said second mesh comprises a 10-40 mesh.   
     
     
         15 . The method of  claim 8 , wherein said ceramic article comprises one or more of the following characteristics: safely encapsulates the hazardous components of said hazardous waste glass, meets EPA standards for toxicity and leaching of said toxic and/or heavy metals, exhibits lead leachate concentrations of less than 5 ppm, exhibits barium leachate concentrations of less than 100 ppm, and exhibits barium leachate concentrations of less than 10 ppm. 
     
     
         16 . A composition comprising a ceramic article comprising hazardous waste glass. 
     
     
         17 . The ceramic article of  claim 16 , wherein said ceramic article is selected from the group consisting of a ceramic tile, a floor tile, and a wall tile. 
     
     
         18 . The ceramic article of  claim 16 , wherein said hazardous waste glass comprises one or more of the following characteristics: greater than 1% lead, greater than 5% lead, greater than 20% lead, CRT glass, fluorescent light glass, greater than 1% barium, greater than 5% barium, and greater than 20% barium. 
     
     
         19 . The ceramic article of  claim 16 , wherein said hazardous waste glass comprises fluorescent light glass. 
     
     
         20 . The ceramic article of  claim 16 , wherein said ceramic article comprises one or more of the following characteristics: greater than 40% hazardous waste glass, greater than 60% hazardous waste glass, greater than 80% hazardous waste glass, greater than 90% hazardous waste glass, safely encapsulates the hazardous components of said hazardous waste glass, meets EPA standards for toxicity and leaching of said toxic and/or heavy metals, exhibits lead leachate concentrations of less than 5 ppm, exhibits barium leachate concentrations of less than 100 ppm, and exhibits barium leachate concentrations of less than 10 ppm.