Lappeenranta Finnsementti Resource Review
Evaluating ways to increase limestone supply from the Nordkalk Quarry to match demand at the recently expanded Finnsementti cement factory.
RESPEC was retained by CRH, PLC to assist in reviewing the Nordkalk Quarry at Lappeenranta, Finland, which provides the raw material to the adjacent Finnsementti cement factory.
In undertaking its evaluation, RESPEC confirmed the limestone reserves available for production; identified the optimum mining mode and plan; prepared a program to implement this optimum plan; highlighted key short-term issues designed to improve the long-term outlook of the quarry; analyzed current mine plans, mining equipment, and processing to identify obstacles; and prepared a program of change to eliminate any hindrances and ultimately raise capacity.
RESPEC evaluated several tactics to increase limestone production. The limestone deposit consists of metamorphosed limestone that is intersected by both granite and amphibolite intrusions. These intrusions decrease the calcium carbonate (CaCO3) content of the rock and have to be removed from the crushed rock to achieve the required quality products. The primary separation criterion is color and removing the darker contaminants is achieved by using optical sorters. To increase production and maximize the efficiency of this process, RESPEC evaluated the upgrade of in-pit sorting by changing the blasting patterns and adjusting the screen sizes to recover more fines before using optical sorters.