METHOD OF ROASTING CARBON-CONTAINING BLANKS Russian patent published in 2000 - IPC

FIELD: manufacture of refractory articles, shaped blanks, bricks, graphite electrodes. SUBSTANCE: molded blanks heated to temperature below decomposition temperature of carbon-containing substances which are bonded or impregnated with carbon-containing substance (pitch) and carbon-containing substance in free state are placed in autoclave, sealed- up, subjected to vacuum treatment and heated under pressure. Blanks are heated to 250-320 C at higher rate as compared with carbon-containing substance in free state and then to roasting temperature at lower rate. Working pressure in autoclave is built up through evaporation of carbon- containing substance and through delivery (if necessary) of heated inert gas (nitrogen); pressure is equal to 10⁸ Mpa at roasting temperature. Then blanks are cooled down and excessive gas is discharged which is later cleaned by thermocatalytic after-burning. EFFECT: increased mechanical strength; reduced open porosity of structure; increased internal coke residue in blanks; reduced emissions of toxic agents into surrounding medium. 4 cl