How is Cement Made?


Cement is used all around the world. It’s used to bind materials are together although very rarely on its own. Cement can also be mixed with some fine aggregates so mortar is produced. It can also be mixed with gravel or sand to make concrete.

But how is cement made and how important is each stage of its manufacture? This article takes a look at how:

Concrete is manufactured using a controlled combination of aluminum, silicon, calcium, iron, and a range of other ingredients. Some of the materials used to make cement include chalk, limestone, marl, or shells.

A combination of these materials are mixed together and are combined with blast furnace slag, iron ore, slate, clay, and shale.

All of the ingredients are heated at a high temperature and to form a very tough substance.  This is then ground down into a very fine powder that we know as cement.

Quality Checks

Many cement plants check every single step of the cement manufacturing process. This is to ensure that the industry specifications are complied with. Stringent chemical analysis is also used to ensure that the right materials are used and are of high-quality.

A Common Way to Manufacture Cement

One of the most common ways to manufacture cement includes using a dry method. The very first step is to quarry all of the materials. Clay, limestone, and a range of other materials are quarried and then crushed which involves 3 different stages of crushing. The rock that has been crushed is then mixed with fly ash or ore. The materials are all mixed together and then ground. The next stage of the process is to feed them into a cement kiln.

The kiln is heated up to 2,700 Fahrenheit in steel rotary kilns that are cylindrical. The kilns are lined with firebrick. One end of the kiln contains the flames and the materials are fed into the opposite end. The heat is controlled by burning powdered coal along with oils and other fuels.

Some elements of the material are removed, the elements that remain are known as “Clinker” and comes out the size of marbles.

Once the clinker is cooled and it is ground down and mixed with limestone and gypsum. A pound of cement contains approximately 150 billion grains, making it ready to be transported. It is now ready to be used in a range of projects around the world.

The History of Cement

The very first cement was made in Leeds, England in the 1800s. It was made by burning some powdered limestone and clay. This was done in a kitchen stove. Using this basic method, the bricklayer Joseph Aspdin metaphorically laid the foundation for the cement industry.

Aspdin helped start the industry that now processes large amounts of materials into a fine powder.

The manufacture of cement is a complicated process that takes a lot of skill and time to get just right. However, when it is manufactured correctly, cement is a material that can last for many years.

Image credit: Cement via okcm/shutterstock