Selection and installation of a vertical roller mill for clinker pregrinding

Roller presses have become well established as a method for increasing the capacity of finish grinding ball mill circuits. While other competing technologies exist, notably the vertical impactor, the vertical roller mill, and most recently the Horomill, none of these has become common in North American cement plants. This paper describes the first application of a modern vertical roller mill as a pregrinder for clinker in North America. The mill has been installed and very recently went into service at Lafarge's Richmond, Canada, cement plant. The reasoning behind the selection of this type of mill is explained, and experience with the installation and commissioning of the equipment is described.