ABSTRACT
Air must be supplied to a composting material for three basic purposes. First, air must be supplied to satisfy the oxygen demand from organic decomposition. Second, air must be supplied to remove water from wet substrates to provide drying. Third, air must be supplied to remove heat generated by organic decomposition to control process temperatures. The aeration rate can be used to control the rate of heat removal and thereby adjust the system temperature. The aeration system is an important feature of all modern composting systems. The ability to control aeration is one of the key points of process control and is an important consideration in process selection. The air requirements for drying and process temperature control are usually much greater than the requirement for biological oxidation. Either drying or temperature control can govern the air requirement depending on process conditions.
