HEM as an Environmental Friendly Alternative to Produce UFC

Abstract

High fineness is one of the most important characteristics of the Ultrafine Cements (UFC) with maximum particle size below 20 μm. Usually, UFC is obtained once the Ordinary Portland Cement (OPC) is grinded in common grinding devices e.g. drum mills; however this is a time consuming process, as it becomes complicated to reduce such a size once the particles have reached ultrafine powder dimensions. Some modern grinding devices as High Energy-Ball Mills (HEM) and shaker mills, have been used for ultrafine grinding-processes, especially at the advanced materials processing research field, but not in the cement industry. The most suitable combination of parameters (time, ball/powder (B/P) ratio and milling speed) was determined after the characterization of processed cement powder, in order to obtain UFC at laboratory level. The optimal combination of parameters produced an UFC having a maximum particle size below 15 μm. The HEM horizontal-rotary-ball-mill device used herein is not only intended for laboratory purposes, but also has one of the advantages of a direct-scaling-up, as it could be used for industrial purposes by means of more capacity mills. Furthermore, it is more efficient than both a shaker mill and a traditional ball milling device. As a result, if this kind of device is used instead of the traditional ball mill, the environmental impact due to the UFC production process could be minimized. This represents an environmental friendly alternative process for obtaining UFC from OPC.