Use of coal mining waste in portland cement production

The article describes the development of a process for producing Portland cement clinker using coal mining waste. It is proposed to include iron ochre in the raw mix as a corrective additive. The clinkers obtained from this raw material and fired at different temperatures contain less free lime than the clinker from traditional raw materials. The proposed raw materials also act as mineralizers increasing the activity of Portland cement clinker, and their use can reduce the firing temperature by 100–150 °C. As a result, in theory, it is possible to reduce CO₂ emissions into the air during clinker production by 12–15 %. Thus, the raw material base of the cement industry is expanded and additional opportunities for the transition to a green economy open up.