Abstract: A process for making an alkaline resistant material comprises the steps of grinding together 0-40% light magnesia, 0-80% roasted magnesia, 10-54% ceramic clay, 0-9% limestone, 1-4% water glass, 0-1.5% carboxymethyl cellusolve, 0-27% talc, 0-3% calcium or barium carbonate to a particle size of less than 50 microns, mixing the ground mixture with water to produce a paste containing <23% wt. water, shaping the paste to a desired shape, drying the shaped product at a temperature of 110 degrees Centigrade, and firing the dried shaped product in a kiln at 1350 degrees Centigrade. The resulting alkali resistant ceramic contains 25-76 wt % MgO, 13-47% SiO2, 5-20 wt % Al2O3, and 1-10 wt % Fe2O3, CaO, K2O, and/or Na2O, with forsterite and spinel being the dominant crystalline phases.

Abstract: The present invention relates to novel ceramic media or ceramic media coatings comprising mainly magnesia, silicon dioxide, and alumina, with forsterite and spinel as the dominant crystalline phases, which show high resistance to alkali attack at high temperature. Ceramic materials having these characteristics are particularly well suited for use as heat-exchange media in regenerative thermal oxidizers (RTOs) for the wood process industry.

Abstract: The present invention relates to novel ceramic media or ceramic media coatings comprising mainly magnesia, silicon dioxide, and alumina, with forsterite and spinel as the dominant crystalline phases, which show high resistance to alkali attack at high temperature. Ceramic materials having these characteristics are particularly well suited for use as heat-exchange media in regenerative thermal oxidizers (RTOs) for the wood process industry.