Abstract: A kiln comprising a cylindrical drum (11) arranged to rotate about a generally horizontal central axis, the drum configured such that rotation will cause particulate material to flow from one end (13) of the drum to the other end (15). The one end being closed by an end assembly (23) fixed relative to a support structure. An inner face of the drum provides a plurality of ports (29) spaced about, and opening into, an interior of the drum,. The ports (29) being connected to the end assembly (23) via a set of passageways (27). The end assembly (23) having an opening (25) connected to a source of air (31) and positioned such that, on rotation of the drum, one or more passageways come into fluid communication with the opening for limiting air flow to the ports.

Abstract: A kiln comprising a substantially cylindrical drum (11) supported from a support structure for rotation about its central axis whereby the drum is supported such that the central axis is generally horizontal and whereby the drum is configured and/or arranged such that rotation of the drum will cause fluid particulate material to flow from one end (13) to other end (15). The one end being associated with a fuel inlet (33) and the other end being provided with a discharge (37) for combustion products and heat. The inner face of the side wall of the drum is provided with a plurality of ports (29) which are located at spaced intervals along and around the interior of the drum and which open into the interior of the drum, the one end being closed by an end assembly (23) fixed relative to the support structure whereby the one end is in close abutting relationship with the end assembly. An opening (25) is provided in the end assembly, the opening connected to a source of air (31).