Abstract: A process for gasifying solid organic matter from wastewater sludge involves dewatering the sludge to a solids content of at least 35% by weight using a combination of centrifugation, microwave heat exchange and screw press separation. The denatured solids are than at least partially pyrolyzed by passing through a heated inclined screw auger. The pyrolysis solids, tars and gases are then gasified by exposure to a high intensity microwave field. Resulting fuel gas and char from the gasification are then separated, with the char then being combusted in a cyclonic char burner to produce vitrified ash and process heat. Fuel gases are cleaned and then burned in internal combustion engines for the generation of electricity and process heat.