APPARATUS AND PROCESS FOR TREATING WASTE

摘要

A method for treating municipal solid waste and other waste is provided which comprises: introducing said waste into a rotary autoclave which is downwardly inclined towards its discharge end and has a door at the discharge end; and injecting steam through said door into said autoclave to treat the load. A method is also provided for treating waste, comprising steam autoclaving the waste, anaerobically digesting an organic-rich fraction of the autoclaved waste, recovering methane-containing gas from anaerobic digestion, internally combusting the methane-containing gas to generate power and exhaust gas, and generating steam for autoclaving using the waste heat. A plant for treating the waste may comprise at least one autoclave for steam treating the waste, at least one anaerobic digestion tank for digesting an organic-rich fraction of the autoclaved waste, a recovery system for recovering methane-containing gas from the or each digestion tank, at least one internal combustion engine for combusting the methane-containing gas and generating power, and a steam generator fed with combustion gas from the internal combustion engine for generating and accumulating steam for supply to said at least one autoclave. Also provided is a method of treating waste material in a rotary autoclave, which comprises: loading the waste material into a top opening of the autoclave whilst rotating the autoclave in a first direction in which screw flights within the autoclave convey the waste forwardly along a downwardly inclined body of the autoclave towards a base of the autoclave; rotating the autoclave in a second direction opposite to the first direction so as to establish a circulation of the loaded material between the upper and lower ends of the autoclave to facilitate vacuum and/or steam treatment thereof; and monitoring the load imparted by the autoclave adjacent upper and lower ends thereof during the reverse rotation, increase of the load adjacent the upper end of the autoclave providing an indication of effective load circulation. A door structure for a commercial-scale autoclave based on a castellated door and a locking ring with lock blocks of inwardly facing U-structure is also provided.