NOVELTY - A unit for roasting and milling large particles (2-5 cm) of biomass in a fluidised bed, has two vertical walls (P1, P2) and inclined wall(s) (P3) defining three zones: (1) a lower zone with means of fluidising particles 2-5 mm in size and with a mill at the bottom, (2) a zone with means of fluidising particles of 1-2 mm and (3) an upper zone with means of fluidising particles smaller than 1 mm, in which the particle feed pipe (11) reaches down to the level of zone 2 and (P3) is at an angle of 30-60 degrees to the vertical.    USE - For roasting and milling lignocellulose-based particles such as wood shavings to give dried sub-mm particles, especially prior to final treatment in a gasification unit or combustion system, or for the preparation of wood shavings for use in other processes such as wine-making.    ADVANTAGE - Enables the simultaneous roasting and milling of biomass particles in the same reactor, resulting in a synergy between the operating conditions for roasting which makes it possible to optimise the operation of the mill. Because the unit functions as a fluidised bed, it is also very easy to process mixtures of biomass particles and other solid particles such as petroleum coke or carbon.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for    (1) A method for roasting and milling biomass particles as above in which    (2) the rate of particle fluidisation in zone 1 is 1.3-2.5 times the minimum rate for particles with a diameter of 1-2 mm    (3) the rate in zone 2 is 1.3-2.0 times the minimum rate for particles with a diameter of 1-2 mm    (4) the rate in zone 3 is 1.3-1.5 times the minimum rate for particles with a diameter of less than 1 mm    (5) the average residence time of the largest biomass particles in the unit is 10-40 (preferably 15-30) minutes and    (6) the temperature inside the unit is 230-300 (preferably 250-280) degrees C    .    DESCRIPTION OF DRAWING(S) - The drawing shows a side view of a fluidised bed roasting/milling unit for operation at atmospheric pressure.    lower, intermediate and upper zones (1, 2, 3)    organs of fluidisation (3, 4, 5)    overflow (6)    fluidised bed in the upper section (7)    particle feed pipe (11)    mill (12)    angle of inclined wall to the vertical. ( alpha )