Abstract: A system for combusting particulate solids comprises a hopper, a furnace and a secondary afterburner. The furnace further comprises at least one exothermic continuous reaction vessel (ECRV) that has a volume that is significantly smaller than the volume of the furnace, which operates at a temperature that is higher than the temperature in the remainder of the furnace, the temperature being high enough to auto-ignite the particulates when they enter the ECRV. The ECRV rotates in unison with a conveyor that delivers the solid particulates from a hopper. The apparatus is energy efficient, with few working parts, and provides combusted particulate solids that can be disposed of directly without environmental concerns.