NOVELTY - Conversion of organic material into hydrocarbon fuel, such as ethanol, comprises fermenting the organic material to provide a fermentation broth; separating the fermented material into a hydrocarbon fuel and a residual product; at least partly converting the residual product into energy; and distributing some of the energy provided by the conversion process to the fermentation process.    USE - The method is for converting organic material (e.g. waste, sludge, and biomass) into hydrocarbon fuel, such as ethanol. Hydrocarbons include oils, such as bio-crude, bio-oil, bio-diesel, and alcohols, such as methanol, propanol, and iso-propanol.    ADVANTAGE - The method achieves cost efficiency, energy efficiency, yield, and new uses of residual products. It provides improved recyclable product. The conversion of residual product is greater than or equal to 90, preferably above 99.9%. The high conversion leads to maximization of the oil production capacity, and minimizes or eliminates the content of unconverted residual product in oil product and mineral product, eliminating the need for a separation step.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a conversion apparatus for converting a residual product into hydrocarbons, comprising a conversion system including a first heating unit for heating a feed of fluid comprising residual product, a catalyst reactor for contacting the feed of fluid comprising residual product with a heterogeneous catalyst, and an adjusting unit for adjusting the fluid to have a pH above 7; and a product recovery system comprising a separation unit, such as a filter, preferably a membrane filter for separating out a first stream of oils and a second stream of water and water soluble organics, preferably water soluble salts being separated out to the first and/or the second stream; and    (2) a plant comprising the conversion apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a flow sheet of bio-ethanol production.