Waste-to-energy conversion system

A pyrolysis conversion method performed by a conversion system comprising:

• a muffle furnace having an inlet end and an outlet end,
• a rotating retort drum within the furnace, said rotating retort drum comprising:
• an inlet sleeve extending through the inlet end of the muffle furnace;
• an outlet sleeve extending through the outlet end of the muffle furnace,
• a rotating retort drum drive applying rotary drive to at least one of said inlet rotating retort drum sleeve and said outlet rotating retort drum sleeve,
• an in-feed auger within a tube within the rotating retort drum inlet sleeve,
• an out-feed auger within a tube within the rotating retort drum outlet sleeve and arranged to deliver syngas and char from said rotating retort drum,
• a char processing system arranged to receive said char,
• a syngas processing system arranged to receive said syngas, and comprising a cracking tower to retain said received syngas at an elevated temperature for a residence time, and
• a gas quench and scrubber system, and
• wherein:
• said inlet sleeve is arranged to provide a gas seal to prevent air ingress or syngas egress to and from the rotating retort drum,
• the rotating retort drum has auger scroll blades fixed to the rotating retort drum wall for conveying feedstock along the drum towards the outlet,
• the rotating retort drum comprises scroll blades of opposite direction for reversal of char movement from an end of the drum and into the outlet auger,
• the rotating retort drum comprises at least one pick-up scoop,
• the rotating retort drum comprises longitudinally-separated barriers between which are radial char retainers for delivery of char into an outlet auger,
• the out-feed auger tube has a char outlet opening on its lower side, which allows char and solid particulate to fall and occupy a lower part of an out-feed hopper,
• and in which syngas occupies any free volume remaining in the hopper, and
• the pyrolysis conversion system comprises a syngas extraction system arranged to extract syngas from the hopper under negative pressure;
• wherein the method comprises feeding feedstock into the retort drum via the inlet sleeve in-feed auger, rotating the retort drum and heating it within the muffle furnace so that the feedstock is pyrolyzed within the retort drum, feeding char and gas out through the out-feed auger, and cracking the gas in the cracking tower.