Comparative Bconomics of Several Alternatives for Bulk Utilization of Fly Ash and Coal Gsification Ash

Abstract

AbstrctFly ash and gasification ash have been evaluated economically for the following uses: partial replacement of Portland cement; mineral wool; blended cement; Sulfurcrete®, high flexural strength ceramic products; ash to upgrade roads; glazed ceramic wall tile; and unglazed floor tile. The ash evaluated is a high-calcium, high-sodium material derived from the Beulah-Zap lignite mined in the Beulah region of North Dakota. Of the uses examined, concrete replacement provided an 8.0% cost saving, blended cement 37.3%, high flexural strength ceramics 52.8%, ash in road construction 44.4%, and wall tile 5.2%. Mineral wool had no replacement savings calculated because blast furnace slag is not available locally to provide a consistent basis. Sulfurcrete® did not provide a cost saving over concrete but its use life and properties are sufficiently different from those of concrete to justify use in some applications, provided that the raw materials are readily available.