Fabrication of MgO-CaZrO3 refractory composites from Egyptian dolomite as a clinker to rotary cement kiln lining

Dolomite is used as basic lining for rotary cement kiln due its high refractoriness, corrosion resistance against basic environments and high coating performance, but its poor hydration resistance limits its use. In this work, Egyptian dolomite was converted into outstanding refractory magnesia-calcium zirconate composite (M-CZ) by the addition of 37.8-47.8 wt% zirconia. The mixtures were milled, uni-axially formed and fired at a temperature of 1400-1550 °C for 2 h. Thermal analysis, phase composition, microstructure, densification parameters, and other technological properties of the fired specimens were investigated. It was found that sintered M-CZ composite with bulk density (3.95 g/cm3), cold crushing strength (170 MPa), and high coating ability can be obtained by firing Egyptian dolomite with 37.8 wt% zirconia at temperature 1500 °C with the formation of belite as a secondary product. This composite can be nominated to be produced on a large industrial scale.