Gas barrier

An apparatus for processing organically coated waste, organic materials, biomass, industrial waste, municipal solid waste and sludge, comprising:

• a rotatable and tiltable furnace having a body portion comprising an interior and a exterior, a single material entry point having a closure movable between an open position in which material can be introduced to the furnace and a closed position in which the interior of the furnace is isolated from the external environment;
• and a tapered portion between said entry point and said body portion of the furnace;
• means for rotating the furnace about its longitudinal axis;
• means for tilting the furnace;
• and at least one director at or adjacent said entry point configured to direct gases in a direction inwardly of said furnace such that a barrier of gas is provided adjacent said opening to inhibit the entrance of oxygen containing atmospheric gas, when said closure is in its open position.