Could non polluting cement be obtained?

It is well known that cement is the product that most pollutes our environment, since cement is the most consumed material in the world (it is used in all kinds of constructions), and in fact it accounts for 7% of all the CO2 pollution we generate.

Many attempts are being made to try to obtain alternative materials to cement, and also to obtain types of cement in a non-polluting way.

Said in a very simple way, cement is obtained from limestone that is extracted from a quarry, and which is then heated to a high temperature (about 1,500 ºC). And it is this process that generates the largest amount of carbon dioxide (polluting gases), both due to the type of energy used and the gases generated in the process.

In the lower drawing I summarize a diagram of the cement manufacturing process.

A team of researchers from North American Universities (Colorado, North Carolina,…) have searched for a new path, and it may be promising. It is about obtaining materials similar to cement starting from algae.

It is a process similar to what happens on reefs. Algae are capable of storing CO2 and generating calcareous materials that can be used in construction. The problem is the time it takes to produce, since the needs for cement are very great, and every day there are more people around the world who move from the countryside to the cities to live.

According to the data of these North American researchers, devoting a surface of 2 million acres to have lagoons where to generate cement, it would be possible to “produce” all the cement that is needed for a year in the USA. And that area is not excessive, since it represents barely 1% of the area dedicated to corn cultivation in the USA.

The idea seems very interesting to me, although I am not an expert in the matter to say whether or not it is viable, but I trust the criteria of the scientists who defend their idea.

A video can be viewed at: https://youtu.be/2Y461Y4Nu9s

The positive aspect of this idea is that the process could be carried out anywhere in the world, and that apparently it does not require excessive technological sophistication.

The “problem” is that we are fighting against time, as we continue to build and pollute more each year that passes. And going from a technological possibility, like the one I just mentioned, to an industrial reality takes many years.

And time is running out on us