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How are limestone and other hard raw materials extracted for cement production?

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Cement The cement-making process, from crushing and grinding of raw materials, through roasting of the ground and mixed ingredients, to final cooling and storing of the finished product.

Hard raw materials used in cement production, such as limestone, slates, and certain shales, are primarily extracted through quarrying. When these rocks are particularly hard, blasting is employed to assist in the extraction process. In some instances, these deposits are accessed using underground mining methods.1

In contrast, softer materials like chalk and clay do not require such intensive methods and can be dug directly by excavators. Once extracted, these materials are transported to crushing plants via various means, including trucks, railway cars, conveyor belts, or pipelines. If the available limestone lacks sufficient lime content, it may undergo beneficiation, such as froth flotation, to remove excess silica or alumina, though this is a costly procedure reserved for when it is unavoidable.1