Recycled magnesia-carbon aggregate as the component of new type of MgO-C refractories

The study focuses on the application of MgO-C scrap without carbon removal step in the composition of new basic products. The compositions containing 0%, 10%, 20% and 30% of recycled aggregate after three different heating treatments (tempering at 200 degrees C, and coking at 1000 degrees C and 1500 degrees C) were prepared. Additionally, the influence of MgO powder fraction was evaluated. Firstly, the utilized recycled aggregates were characterized in terms of their physicochemical properties. The tempered samples were subjected to comprehensive thermal analysis by DTA-TG-MS and LECO. Then, the densification, mechanical, thermomechanical and elastic properties of the produced materials containing recycled aggregates were investigated. The examinations were supplemented with microstructure observations by SEM/EDS. The results indicated that the addition of recycled MgO-C aggregate into the composition of new magnesia-carbon bricks do not worsen their properties. The optimal content of recycled raw material was 30 wt%.(C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The study explored the use of MgO-C scrap in new basic products without the need for a carbon removal step, finding that adding recycled aggregates did not worsen the properties of the materials. The optimal content of recycled raw material was determined to be 30%.