Energy and Environmental Issues Related to Binder Production

ENERGY AND ENVIRONMENTAL ISSUES RELATED TO BINDER PRODUCTION 

If phosphate binders were widely used for constmction, very large volumes of them would replace conventional cement. It is, therefore, important to assess the effect of these binders on energy usage and the environment and to compare the results to the corresponding 

The author acknowledges help from Matt Aro of University of Minnesota, Duluth, in calculating these numbers. 

Coupled with the energy consumption is the environmental effect from production of these binders. For every ton of phosphoric acid, 5 ton of phosphogypsum (calcium sulfate) is produced [15]. This waste can be recycled into value-added products such as gypsum board, but often there is a radioactivity issue. Some phosphogypsum contains radium and emanates radon gas. At the present time, such waste can only be disposed in a landfill. 

Clinkering of cement has its own environmental effects. Every ton of cement generates 2 ton of CO2, one ton due to the limestone that is decomposed into calcium oxide and CO2, and the other due to burning of fuel [16]. This gas releases to the environment and hence is not controlled. Thus, the choice is between land filling for phosphate ceramics and releasing CO2 into the atmosphere without any control for cement. 

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