A method and apparatus for incinerating different types of combustible waste in a cement manufacturing process. Two combustion chambers for incinerating waste are arranged in series, with first combustion chamber being a down draft chamber in which there is a downward flow of combustion gas and waste fuel to a waste and gas outlet. The second chamber is adaptable to support waste on a supporting surface incorporated in the compartment, wherein the waste is transported through the compartment from a waste inlet to a waste outlet along a circular path.