Cement grinding optimisation

Abstract

The current world consumption of cement is about 1.5 billion tonnes per annum and it is increasing at about 1% per annum. The electrical energy consumed in cement production is approximately 110 kWh/tonne, and around 40% of this energy is consumed for clinker grinding. There is potential to optimise conventional cement clinker grinding circuits and in the last decade significant progress has been achieved. The increasing demand for “finer cement” products, and the need for reduction in energy consumption and green house gas emissions, reinforces the need for grinding optimisation. This paper describes the tools available for the analysis and optimisation of cement grinding circuits. The application of the Bond based methodology as well as Population Balance Models (PBM) is presented using a case study. The throughput of current conventional closed grinding circuit can be increased by 10–20% by pre-crushing the clinker using the Barmac crusher. A potential for application of stirred milling technology for fine cement grinding was also discussed.