Compact dual cyclone combustor

A method for combusting combustible materials, comprising the steps of:

• (a) introducing the combustible materials into a vertical combustion chamber comprising a top;
• a bottom;
• a substantially cylindrical side wall connecting the top and bottom;
• a conical surface located inside the chamber below and near the top;
• a burner located inside the chamber, above and near the bottom;
• a conical mesh positioned above the burner;
• and at least one load bin mounted in the side wall;
• wherein the combustible materials are introduced into the chamber through the load bin onto the conical mesh;
• and wherein the chamber and the load bin are adapted to permit combustible material to be loaded into the chamber through the load bin while combustion in the chamber is ongoing;
• (b) introducing fuel from an external fuel source to the burner, and igniting the fuel;
• (c) generating a vortex by blowing air into the combustion chamber near the bottom, so that an ascending vortex is induced in hot gases leaving said burner, and so that the ascending vortex is converted by the conical surface to a descending vortex located centrally inside the ascending vortex;
• wherein the shear between the ascending and descending vortices enhances mixing of oxygen and uncombusted combustible materials;
• and
• (d) separating ash from gases in the descending vortex centrally near the bottom, and causing the separated gases to exit the chamber.