Physical and technical properties of materials for lining thermal units with phosphate binders

The results of obtaining refractory materials and products for lining thermal units are presented. Technogenic refractory waste with a high content of corundum fractions ranging from 7 to 0,5 mm (70‒85 wt. %) was used as a filler. To create a ceramic-chemical binder, refractory kaolin clay (10‒25 wt. %) and orthophosphoric acid (13‒15 wt. %) were used. The experimental samples were molded by tamping, followed by subsequent heat treatment in the range of 100 to 1200 °C. The influence of the grain composition and heat treatment temperature of the prepared mixture on the change in the phase composition and physical and technical properties of the samples has been established. Refractory materials based on phosphate binders with a medium-grained corundum-containing filler had a compressive strength of 21 MPa, an open porosity of 19 %, and a thermal conductivity of 1,46‒1,83 W/(m·K) at (650±20) °C. Ill. 4. Ref. 15. Tab. 3