Operation of MVR mills in cement manufacturing - A status report

For decades, vertical roller mills have been in use in the cement industry for grinding cement raw material and coal. Since the 1980s this mill type has also been used for combined or separate grinding of cement clinker and additives. In the last two decades the number of installations for grinding cement and blast-furnace slag has increased remarkably. The well-established and proven MPS mills have been used for the combined drying and grinding of cement raw material, coal, cement clinker, blast-furnace slag and composite cements for many years. The trend in the cement industry is towards ever increasing capacities of individual grinding plants. Therefore, the need for high plant availability and an optimized maintenance concept is becoming more and more important. The MVR vertical roller mill with an installed power of up to 12000 kW is a tailor-made concept to fulfil these requirements. The first MVR mills were installed in Europe for cement raw material and cement grinding. These mills have been in operation since 2007 or 2008 respectively. Meanwhile the worldwide distribution of MVR mills has increased continuously. A large number of MVR mills have been ordered by Indian cement manufacturers. In this contribution, the operating data of several MVR mills installed in India will be discussed in detail.