NOVELTY - Composting system comprises: a horizontal composting chamber (1) constructed as a stationary, covered channel which is fully enclosed or a stationary, cylindrical vessel; and an internal transport system which conveys composting material from one end of the chamber to the other in a continuous or batch process. The chamber is adapted so that air emissions from within the chamber can be controlled. The transport system is based on a central shaft, or series of shafts (7) on the center of the chamber which have a series of discrete arms (5) that extend into the outer volume of the chamber.    USE - Used as a composting system.    ADVANTAGE - The composting system: is horizontal and in-vessel; and utilizes the chamber which minimizes the loss of heat generated during the composting process.    DETAILED DESCRIPTION - Composting system comprises: a substantially horizontal composting chamber (1) constructed as a stationary, covered channel which is fully enclosed or a stationary, substantially cylindrical vessel; and an internal transport system which conveys composting material from one end of the chamber to the other in a continuous or batch process. The chamber is adapted so that air emissions from within the chamber can be controlled. The transport system is based on a substantially central shaft, or series of shafts (7) substantially on the center of the chamber which have a series of discrete arms (5) that extend into the outer volume of the chamber. The discrete arms are arranged in a helical fashion on the shaft(s) so that when the shaft(s) are rotated they move the material in one direction or the other along the chamber, depending on the direction of rotation of the shaft(s). The transport system is under the control of a microprocessor based system which records inputs from various probes on the chamber which determine the optimal air speed as a function of the headspace air temperature and gaseous content in the chamber.    DESCRIPTION OF DRAWING(S) - The figure illustrates a perspective view from an inlet end of an continuous composting unit.    Chamber (1)    Feed chute (2)    Arms (5)    Shafts (7)    Bearings (8)