How much limestone is needed to make cement?

The amount of limestone required to make cement can vary depending on the specific type of cement being produced. However, limestone is a key ingredient in the production of cement and typically constitutes about 70-80% of the raw materials used.

In the manufacturing process of cement, limestone is combined with other materials such as clay or shale. These materials are ground into a fine powder, known as raw meal or raw mix, which is then heated in a kiln to temperatures of around 1,450 degrees Celsius (2,642 degrees Fahrenheit). This process, known as calcination, causes chemical reactions to occur, resulting in the formation of clinker.

Clinker, the intermediate product obtained from the kiln, is then finely ground with a small amount of gypsum to produce cement. The exact proportion of limestone in the raw mix can vary, but it generally falls within the range of 70-80%.

It's important to note that cement production involves additional components and processes apart from limestone, such as silica, alumina, iron oxide, and other additives. These materials are used to achieve specific properties and characteristics in the final cement product.

Overall, limestone is a crucial component in the production of cement and comprises a significant portion of the raw materials used in the manufacturing process.