Prospects of the Irkutsk Region hydro-removal ash usage as the main raw material for construction ceramics production

The article presents results of research on assessing the possibility of construction ceramics with hydro-removal ash (HRA) as the main raw material production. The main objects of the research were the HRA from TPP-10 and TPP-9, chosen because of the total ash accumulation volume, amounting to 48 thousand tons and proximity of the ash dumps to the existing ceramic Irkutsk brick production. The article presents physicochemical characteristics of the studied HRA, as well as structural and physicomechanical characteristics of the ceramic crock obtained from the HRA. Following methods were used: X-ray diffraction analysis, X-ray fluorescence analysis, TGA-thermogravimetric analysis, petrographic analysis, SEM-scanning electron microscopy, laser diffraction. During the research, including regression analysis method, the optimal conditions for construction ceramics from HRA obtaining were determined as well as the HTA optimal specific surface and the ceramic crock calcination mode and duration. The 100% HRA ceramic crock strength depends on the calcination mode and the HRAs specific surface area and may vary from 12 to 75 MPa. The main quality indicators for construction ceramics comply with GOST 530–2019 “Ceramic brick and stone. General specifications”. The obtained quality indicators values allow concluding that it is fundamentally possible to use the studied hydro-removal ashes as separate raw material for the construction ceramics production with semi-dry pressing method.