NOVELTY - A method which involves: (a) providing a biomass feedstock containing cellulose and water; (b) contacting the biomass feedstock with hydrogen in the presence of a catalyst capable of activating molecular hydrogen to form a hydrocatalytically treated mixture; (c) separating the hydrocatalytically treated mixture into at least a first bottom fraction and a first overhead fraction; (d) vaporizing at least one volatile organic compound from the first bottom fraction in a first flasher; (e) depositing the at least one compound having a separation point.    USE - The methods and systems are useful for supplying hydrogen to a hydrocatalytic reaction, and for treating a biomass feedstock to form a fuel blend (claimed).    ADVANTAGE - The methods and systems provide efficient conversion of cellulosic biomass into fuel blends and other materials.    DETAILED DESCRIPTION - A method which involves: (a) providing a biomass feedstock containing cellulose and water; (b) contacting the biomass feedstock with hydrogen in the presence of a catalyst capable of activating molecular hydrogen to form a hydrocatalytically treated mixture; (c) separating the hydrocatalytically treated mixture into at least a first bottom fraction and a first overhead fraction, where the first bottom fraction comprises (i) at least one compound having a separation point at a temperature range of 100-600 degrees C and a pressure of about atmospheric pressure, and (ii) one or more volatile organic compounds; (d) vaporizing at least one volatile organic compound from the first bottom fraction in a first flasher; (e) depositing the at least one compound having a separation point having a temperature in a range of 100-600 degrees C and a pressure of about atmospheric pressure on a surface in the first flasher; (f) placing the first flasher in standby mode; (g) vaporizing at least one volatile organic compound from the first bottom fraction in a second flasher; (h) partially oxidizing the deposited at least one compound in the first flasher to generate a gas mixture comprising hydrogen and carbon monoxide; (i) providing the gas mixture to a water gas shift reaction zone external to where the biomass feedstock is contacted with hydrogen to generate hydrogen and carbon dioxide; and (j) providing the hydrogen from step (i) for use in step (b). An INDEPENDENT CLAIM is a biomass conversion system which comprises: a hydrocatalytic treatment system configured to allow contact of a biomass feedstock with hydrogen in the presence of a catalyst capable of activating molecular hydrogen to form a hydrocatalytically treated mixture; a first separation zone coupled to an output of the hydrocatalytic treatment system to receive the bottom fraction, the first separation zone configured to separate the hydrocatalytically treated mixture into at least a first bottom fraction and a first overhead fraction, where the first bottom fraction comprises (i) at least one compound having a separation point having a temperature in a range of 100-600 degrees C and a pressure of about atmospheric pressure, and (ii) one or more volatile organic compounds; a recovery and gasification system coupled to an output of the first separation zone, the recovery and gasification system configured to partially oxidize the first bottom fraction to produce a gas mixture comprising carbon monoxide and hydrogen, where the recovery and gasification system comprises: a first flasher coupled to the separation zone to receive the first bottom fraction; a second flasher coupled to the separation zone to receive the first bottom fraction; where the recovery and gasification unit is configured to operate one of the first and second flashers to vaporize at least one volatile organic compound in the first bottom fraction while the other flasher is in standby mode, where each of the first and second flashers is adapted to gasify a compound from the bottom fraction deposited on a surface in the flasher to generate the gas mixture; and a water-gas shift reaction zone coupled to an outlet of the recovery and gasification system to receive the gas mixture, the water-gas shift reaction zone is configured to convert the gas mixture into hydrogen and carbon dioxide, where an outlet of the water-gas shift reaction zone is coupled to the hydrocatalytic treatment system.