Waste from coal-fired power plants will make alumina production cheaper

Scientists from the Vernadsky Institute of Geochemistry and Analytical Chemistry (GEOCHI) of the Russian Academy of Sciences (Moscow), Ural Federal University (Ekaterinburg), and Tongji University (China) have developed an improved technology for producing high-quality alumina from ash and slag, in which the feedstock is sequentially treated with several chemical reagents.

The authors used ash from Reftinskaya TPP, one of the largest coal-fired power plants in Russia, located in the Sverdlovsk region.

"The main innovation of the proposed method was the ability to precipitate aluminum in the form of alunite without using additional reagents, such as gaseous ammonia. The use of bemite (mineral) rather than traditional gibbsite as an inoculum allowed to reduce the temperature of alumina calcination by 300 °C. Thus, energy costs are reduced by 30%", - told "Izvestia" project manager, candidate of technical sciences, leading researcher of the laboratory of sorption methods GEOCHI RAS Dmitry Valeev.

Chemical analysis showed that the particle size and purity of alumina produced by the proposed method meet the requirements of state standards of Russia, China and India. Therefore, the obtained product can be used by domestic and foreign plants.

Read more in the exclusive material of Izvestia:

On the ash of times: waste from coal-fired power plants will make aluminum production cheaper