Abstract: A continuous reactor vessel for a rotary reactor having a first disk and a second disk separating three zones wherein the first disk includes a material feed opening spaced from its peripheral edge by an inlet peripheral spacing and configured to receive a material inlet tube, the second disk including an axial extension spaced from the second peripheral edge having at least one axially extending side wall and an end cap with at least one reaction zone discharge opening in the extension. The at least one opening allowing for a continuous and controlled reactor discharge rate of the associated granular product from the reaction zone into the discharge zone, the discharge opening being spaced from the second peripheral edge by an outlet peripheral spacing such that the peripheral spacings define a controlled depth of a dead bed accumulation of the associated granular product in the reaction zone.