Abstract: An incinerator for burning garbage has a combustion chamber and an after-burner chamber. The top wall of the combustion chamber has an open loading aperture therein. An air curtain of over-fire combustion air is provided below the loading aperture, to prevent exhaust of gases and suspended solids through the loading aperture, by means of a slot jet extending the length of the combustion chamber and directing a stream of air across the chamber. This air is also used as combustion air, along with under-fire air supplied to the bottom of the chamber and further air supplied to the after-burner chamber. Efficient combustion air flow patterns are established reducing the over-all requirement for combustion air in the incinerator of the invention.

Abstract: An incinerator for pasty or sludge-like wastes includes a fixed hearth within its combustion chamber defining a surface for the burning thereon of a layer of the waste material. The surface of the hearth is sloped downwards toward an ash receiving region to provide for movement of the burning waste materials which are introduced through waste inlet ports. The hearth has a downward slope which progressively increases towards said ash receiving region thereby to compensate for the gradually increasing consistency of the burning materials and thus provide for their continued movement over the hearth surface under the influence of the gravitational forces thereon. The furnace also includes means for providing a rotating flow of burning gases and combustion air within the chamber thereby to ignite and support the combustion of the sludge on the hearth surface.