NOVELTY - Organic waste (10), e.g. organic refuse and sludge, is subjected to methane fermentation to form digested sludge (15). The digested sludge is dehydrated, the compost fermented and dried to form solid fuel. The water vapor generated by the compost fermentation is condensed. The condensed latent heat is collected and used for compost fermentation.    USE - For processing organic waste, e.g. organic refuse and sludge, to form solid fuel for use in fuel cell.    ADVANTAGE - The solid fuel of high safety is produced with a high moisture content and low methane conversion ratio. Since the exhaust heat of electricity generation is used as heat source for heating the fermentation tank, usage of rational exhaust heat is enabled. The system of high economical electricity generation efficiency is provided by utilizing solid electrolyte type fuel cell. Since energy efficiency is high, the system is applicable for processing various organic waste. The scrap amount of resources emitted from each area is reduced by using the processing system and the energy generated from the waste material is efficiently used.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for processing system of organic waste.    The system has a methane fermentation tank (2) for methane fermentation of the organic waste, dehydration unit (3) for dehydrating the digested sludge emitted from the methane fermentation, a drier (5) for adjusting water content of dehydrated sludge and a solidification unit (6) for forming solid fuel. The system has a compost fermentation tank (4) for aerobic fermentation of the dehydrated digested sludge, provided to front stage of the drier. The heat generated by compost fermentation tank is collected with a heat exchanger (8) and utilized for heating the compost fermentation tank.    DESCRIPTION OF DRAWING(S) - The figure shows the flowchart of waste disposal system for processing organic waste. (Drawing includes non-English language text).    Electrical power generating device (1a)    Methane fermentation tank (2)    Dehydration unit (3)    Compost fermentation tank (4)    Drier (5)    Solidification unit (6)    Heat exchanger (8)    Organic waste (10)    Methane (12)    Digested sludge (15)    Dewatered sludge (17)    Exhaust gas (21)