Thermal reactors

A thermal reactor comprising a furnace vessel having a vertically aligned exterior shell, an upstanding partition shell coaxially located inside the exterior shell and disposed within the lower region thereof to define within said vessel, on the opposing sides of said partition shell, first and second coaxial compartments in communication with each other adjacent both the upper and lower regions of said partition shell, an air permeable bottom wall formed in said exterior shell below said partition, said bottom wall being inclined downwardly from said first to said second compartment, a mass of particulate material forming a first bed in the first compartment, a further mass of particulate material forming a second bed in the second compartment, the upper surfaces of said first and second beds, in the static condition of the reactor, being below the level of the top of the partition shell, diverter means located at least above the second compartment and extending toward said first compartment and spaced above said partition shell to define, with the top of the partition shell, an outlet slot from the second compartment into the first compartment, means for fluidizing both said first and second beds, including means for controlling the fluidization of each of said first and second beds respectively such that the fluidization of the first bed is substantially uniform and to a lesser extent than the fluidization of the second bed, and the material in the first compartment is caused to flow generally downwardly and the upper surface thereof remains below the level of the top of the partition shell, and the material in the second compartment is caused to flow generally upwards at a velocity to impinge on said diverter means and be deflected by said diverter means through said outlet slot as a substantially horizontal cascade extending right across and falling onto, the entire area of the upper surface of the first bed, and in conjunction with said bottom wall to establish continuous circulation of material around the upstanding partition shell, at least one inlet means from the exterior of the furnace vessel for supplying material to be reacted to the upper region of said first compartment, and at least one outlet means from the second compartment for discharging non-combustible product and bed material and a flue outlet communicating with said first and second compartments for discharge of gas.