NOVELTY - Producing (I) bio-oil, comprises: (a) supplying a particulate biomass material to a gas mixing zone; (b) supplying a carrier gas to the gas mixing zone; (c) transporting the biomass material through a reducer located downstream of the gas mixing zone, where the reducer defines a flow pathway having a diminishing cross-sectional flow area; and (d) transporting the biomass material through a feed line and into a reaction zone (604), where the feed line is located downstream of the reducer, and the carrier gas is used to propel the biomass material during step (d).    USE - The process is useful for producing bio-oil.    ADVANTAGE - The process utilizes the biomass conversion system which is capable of efficiently feeding biomass into a processing location.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: producing (II) bio-oil, comprising (a1) supplying a particulate biomass material to at least one gas mixing zone, (b1) supplying at least one carrier gas stream to the gas mixing zones, and (c1) transporting the biomass material from the gas mixing zones into a reaction zone via first and second feed lines, where the first and second feed lines supply the biomass to the reaction zone via respective first and second spaced reactor inlets, and the carrier gas streams are used to propel the biomass material during step (c1); #producing (III) bio-oil, comprising (a2) introducing a first quantity of biomass material into a first hopper, (b2) transporting the first quantity of biomass material from the first hopper into a second hopper, (c2) introducing a second quantity of biomass material into the first hopper, (d2) pressurizing the second hopper with a gas while the first quantity of biomass material is located in the second hopper, (e2) transporting the second quantity of biomass material from the second hopper to a pressurized feed system, (f2) depressurizing the second hopper by releasing at least a portion of the gas from the second hopper, (g2) routing at least a portion of the gas released in step (f2) to the first hopper, and (h2) using the gas routed from the second hopper in step (g2) to at least partially purge oxygen from the second quantity of biomass material inside the first hopper; and #a biomass conversion system comprising a biomass source for providing a solid particulate biomass material, a carrier gas source for providing carrier gas, the gas mixing zones coupled to the biomass source and the carrier gas source and configured to receive the biomass material from the biomass source and to receive the carrier gas from the carrier gas source, a biomass reactor comprising first and second spaced-apart reactor inlets, a first feed line providing fluid flow communication between the gas mixing zones and the first reactor inlet, and a second feed line providing fluid flow communication between the gas mixing zones and the second reactor inlet.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of biomass conversion system.    Biomass feed system (602)    Reaction zone (604)    Solids separator (606)    Condenser (610)    Cooling mechanism (612)