Novosibirsk State Technical University (NETI) has proposed using scrap refractory fireclay bricks as secondary raw materials for the manufacture of thermal insulation building materials.
The processing of man-made waste, such as fireclay brick scrap, is important from the point of view of resource conservation and environmental safety. The use of recyclables leads not only to a reduction in the amount of waste and a reduction in the negative impact on the environment, but also contributes to the development of innovative materials for various industries.
"We decided to create a new material with thermal insulation properties that could be used in the construction industry. Man-made waste based on scrap refractory fireclay bricks was used as the main raw material for the production of samples. Scrap bricks were crushed and fractionated using special equipment at the Department of Environmental Engineering of NSTU-NETI. A silicate binder developed at the Institute of Solid State Chemistry and Mechanochemistry of the Siberian Branch of the Russian Academy of Sciences was used for binding, which is similar in characteristics to liquid glass, but much cheaper to manufacture. To obtain composites with high performance properties, it was necessary to select the ratio of the fractional composition of the filler, the content of silicate binder and foaming agent. This is what we did, which led to the creation of durable, lightweight and porous samples. The manufacture of composites was reduced to the classical technique of slip casting of foamed mass: mixing with subsequent foaming of the initial components and pouring the foamed mass into molds, then drying at room temperature and at 50 ° C. After removing all moisture from the samples, they were fired at different temperatures from 300 to 900 ° C, and then their properties were investigated," said Alexandra Samusova, a graduate of the Faculty of Aircraft at NSTU-NETI.
In total, more than 40 series of samples from man-made waste based on scrap refractory fireclay bricks were created. The characteristics of composites with different fractional filler composition and silicate binder content, as well as the type and amount of foaming agent, were studied. The main characteristics for the study were chosen: compressive and flexural strength, density, thermal conductivity, and water resistance. At the same time, the dependence of the change in the characteristics of the material on the firing temperature was analyzed.
As a result of fruitful cooperation between the university and the academic institute, it was possible to develop a structural and thermal insulation material based on man-made waste, which is not inferior in characteristics to thermal insulation materials available on the Russian market.
As Alexandra Samusova noted, competent recycling of man-made waste, including refractory materials, is promising. The developed composite material can be used for thermal insulation in the construction industry, for example, in the manufacture of brick kilns (for domestic and industrial purposes). The continuation of research will not only reduce the environmental burden on the regions of Russia, but also expand the raw material base for the production of various products both in industry and in everyday life.
Earlier, NSTU-NETI proposed using polymer waste to create building materials.