NOVELTY - Converting a biomass feed composition to a product of a carbonaceous material and a hydrocarbon material in a ribbonchannel reactor (122) involves feeding feed composition in reactor; rotating first heated surface relative to second heated surface; forming a spiral ribbon of feed composition between first and second heated surfaces; and heating spiral ribbon to generate a vapor comprising hydrocarbon material and a solid comprising carbonaceous material, where feed composition comprises at least one biomass material decomposable into product.    USE - For converting a biomass feed composition to a product comprising a carbonaceous material and a hydrocarbon material in a ribbonchannel reactor (claimed).    ADVANTAGE - The process with fast, efficient, relatively small and simple system receives, pyrolyzes and recovers useful hydrocarbon products from waste plastics in an economically efficient manner; is relatively free of technical difficulties arising from the very nature of the raw materials; provides carbohydrate-based materials into usable fuels such as charcoal and liquid hydrocarbons which are economical and efficient; allows recovery of non-condensable but combustible gases containing a sufficient quantity of heat-producing capability to heat; provides all needed energy for operation of the overall process; dose not require high pressure.    DETAILED DESCRIPTION - Converting a biomass feed composition to a product comprising a carbonaceous material and a hydrocarbon material in a ribbonchannel reactor (122) containing a first heated cylindrical surface and a second heated cylindrical surface spaced away from the first heated cylindrical surface, involves feeding the biomass feed composition in the reactor; rotating the first heated surface relative to the second heated surface; forming between the first heated surface and the second heated surface a spiral ribbon comprising the biomass feed composition; and heating the spiral ribbon to generate a vapor comprising the hydrocarbon material and a solid comprising the carbonaceous material, where the feed composition comprises at least one biomass material decomposable into the product. An INDEPENDENT CLAIM is included for an apparatus (112) for producing hydrocarbon materials from a biomass feed composition comprising a feed port; a drying apparatus for drying the biomass feed composition; a thermal decomposition assembly comprising a ribbonchannel reactor containing (a) an inner heated hollow cylinder (124); and (b) an outer heated hollow cylinder (126), where the inner heated cylinder is concentric and rotatable with respect to the outer heated hollow cylinder, and both heated hollow cylinders provide heat for increasing temperature of the feed composition to convert the feed composition into (i) a vapor fraction and (ii) a solid residue fraction; (c) low height flighting mounted with respect to the inner heated hollow cylinder and the outer heated hollow cylinder adapted to move the feed composition towards a distal portion of the thermal decomposition assembly; (d) at least one vapor port (134) for removing the vapor fraction; and (e) at least one solids port at the distal portion of the thermal decomposition assembly for removing the solid fraction.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic depiction of a thermal decomposition apparatus and portions of a process.    Apparatus (112)    Ribbonchannel reactor (122)    Inner heated hollow cylinder (124)    Outer heated hollow cylinder (126)    Vapor port (134)    Condenser (140)