Treatment of waste products

Abstract

A method for the encapsulation of fine particulate materials includes treating these materials with a microfine hydraulic inorganic filler which, typically, includes a cementitious material, such as Portland Cement. The filler is ground to a much smaller particle size than is normally used in the production of a grout and is provided in the form of an aqueous composition for the treatment of the fine particulate materials by pumping under pressure through these materials such that they become intimately encapsulated. The method is particularly applicable to the treatment of waste materials and, most particularly, waste materials, which are encountered in the nuclear industry.

1 . A method for the encapsulation of fine particulate materials comprising: 
 treating said materials with a microfine hydraulic inorganic filler.    
     
     
         2 . A method as claimed in  claim 1  wherein the microfine hydraulic inorganic filler comprises a cementitious material.  
     
     
         3 . A method as claimed in  claim 2  wherein the cementitious material comprises Portland Cement.  
     
     
         4 . A method as claimed in  claim 2  wherein the microfine hydraulic inorganic filler further comprises at least one inorganic filler selected from the group consisting of blast furnace slag, pulverised fuel ash, hydrated lime, finely divided silica, limestone flour and organic and inorganic fluidising agents.  
     
     
         5 . A method as claimed in  claim 1  wherein the filler is ground to a much smaller particle size than is normally used in the production of a grout.  
     
     
         6 . A method as claimed in  claim 4  wherein the filler has a maximum particle size of less than about 10 μm.  
     
     
         7 . A method as claimed in  claim 1  wherein the microfine hydraulic inorganic filler is provided in the form of an aqueous composition.  
     
     
         8 . A method as claimed in  claim 7  wherein the water content of the composition is approximately 40-50% (w/w).  
     
     
         9 . A method as claimed in  claim 7  wherein said aqueous composition is pumped under pressure through the fine particulate materials in order to achieve intimate encapsulation.  
     
     
         10 . A method as claimed in  claim 1  wherein the fine particulate materials comprise waste materials.  
     
     
         11 . A method as claimed in  claim 10  wherein said waste materials comprise waste materials generated in the nuclear industry.  
     
     
         12 . A method as claimed in  claim 10  wherein said waste materials comprise filters containing ion exchange resins.  
     
     
         13 . A method as claimed in  claim 12  wherein said filters are utilised in the removal of caesium from waste ponds.  
     
     
         14 . A method as claimed in  claim 1  wherein said fine particulate materials are treated in containers, without the requirement for removal from said containers prior to treatment.  
     
     
         15 . A method as claimed in  claim 14  wherein the container is used as part of the waste packaging.