| abstract |
In order to provide a method and apparatus for processing solid mixed organic waste to produce a fuel or organic compost, the waste material is treated in a rotary aerobic digester (116), where it is digested in the thermophyllic phase at a temperature in the range 60-75'C, the oxygen content of the gas in contact with the material being treated being maintained at a level above 5% by volume, to produce a treated material having a moisture level not exceeding 45% by weight, more preferably not exceeding 35% by weight and most preferably not exceeding 25% by weight. The treated material can be subsequently dried on a drying floor (123) to provide a stable product. Waste having a high moisture level, such as domestic waste is blended in a blender (115) with waste having a lower moisture level, such as commercial waste, to provide control of the properties of the waste being treated and of the product obtained. The treated solid mixed organic waste from the aerobic digester may also be pyrolysed and, optionally, subsequently gasified. |