Innovation of an economically viable process for the production of building materials in Russia

Researchers from Russia’s National Research Technological University “NUST MISiS”, together with colleagues from Belarus, have designed a new technology for obtaining special raw materials for the production of building materials.
According to the researchers, what distinguishes this design from its counterparts is its environmental friendliness, simplicity and low cost. It is worth noting that this research was published in the Journal of Environmental Chemical Engineering.
Calcium sulfate anhydrite is an important base for the production of building materials. Russian University researchers note that while the cost per ton of gypsum (which is the basis for calcium sulfate anhydrite production) is estimated at about $20, which is equivalent to about 1,480 rubles, the cost of a ton of anhydrite is 300- 400 dollars, equivalent to (22,200 – 29,600) rubles, mainly due to high-temperature processing when produced.
In order to reduce the cost and simplify the technique of producing calcium sulfate anhydrite, the scientists proposed a method for producing it in an aqueous medium within the framework of one stage of the mixing and composition process, as obtaining it until this moment is through sulfuric acid and a carbon component in two main stages: obtaining gypsum and then Production of anhydrite from it.

In this context, the researchers proposed a method for producing anhydrite from slaked lime suspension (waste from industrial wastewater treatment) and sulfuric acid in an aqueous medium, so that an index of product purity in terms of the main component is obtained by at least 99%.
Most anhydrite production techniques are based on high-temperature roasting (800-1000 °C) in rotary kilns. The new technology proposed by the researchers is used in an aqueous reactor at a temperature of only 45-55 °C, based on production waste, which in turn leads to savings of resources and fuel.
The advantage and novelty of this method lies in the simplicity of the technological design of the devices, the low temperature and fusion pressure index. Thus, the cost of the anhydrite obtained by the new method will remain at the level of the cost of the raw material – gypsum.

Valentin Romanovsky (left), one of the Leading Experts at MISIS University’s Center for Structural Ceramic Nanomaterials, and co-author Maxim Komarov, a graduate student at the Institute of General and Inorganic Chemistry at the National Academy of Sciences of Belarus.

The researchers believe that the new technology can be used in enterprises where waste sulfuric acid or slaked lime is formed, or in enterprises that produce dry building mixtures. The scientists based on this research confirm that the results obtained can find applications for them in the construction, chemical, medical and other industries.
In this regard, researcher Valentin Romanovsky, a prominent expert in the Research Center for Structural Ceramic Nanomaterials, at NUST MISIS, said:
“We did research on the most realistic synthesis conditions, where we used production waste as raw materials. Knowing that this waste is practically not reused and refined, and if it is used it is mainly used in simple and cheap processes and industries. By adding a little chemistry to the process The processing managed to get a fairly expensive product.”
The team of scientists is currently faced with the task of activating the binding properties of the resulting material and studying its main properties, since the full potential of synthetic anhydrite has not yet been studied. While preliminary studies have shown that its main properties are not inferior to, and in many cases superior to, the main properties of anhydrite obtained by the thermal method.
However, in the future, researchers will work on designing composite materials based on synthetic anhydrite and on dry building mixtures built as well.