Bottom Ash of the Largest Kuzbass Coal Power Plants: Secondary Use Possibility

Abstract

Kemerovo district coal power plant, Tom-Usinskaya district coal power plant and Belovo district coal power plant are the largest coal power plants in Kuzbass and during the combustion of coal they generate annually about 1600 tons of coal ash which consists of fly ash and bottom ash. Almost all the generated ash is disposed into ash dumps except a small quantity of fly ash (3.5%) that is effectively utilized. Therefore, secondary use of the bottom ash can be a sustainable solution for reducing its by-products and overcoming the scarcity of raw materials required for construction work. Therefore, the main aim of this research was to determine the chemical composition and granulometric properties of bottom ash to find out the possibility of using it as raw material for the building materials production. A series of laboratory experiments were conducted to determine basicity index, activity index, average grain density, bulk density, true density and grain size distribution. The experimental results reveal that the particle size of ash is predominantly sand-sized while containing some silt-sized and rubble-sized fractions as well. The studied bottom ash has a low basicity and activity index, respectively, does not have independent hydraulic activity. Thus, bottom ash of the largest Kuzbass coal power plants can be used as raw material for the building materials production.