A method for the continuous production of a combustible material for an industrial boiler, corresponding material and installation

A method for manufacturing a combustible material having a lower heating value greater than or equal to 5.29 MWh/t, for an industrial boiler, from wood chips, at least 10 wt % of the wood chips being derived from hardwood, wherein the method comprises:

• obtaining wood fragments with a moisture content of between 5 and 25% from these wood chips;
• continuously introducing a predetermined volume per minute of said obtained wood fragments into a pressurised reactor, said reactor being supplied with substantially saturated steam at a pressure of between 15.6 and 23.2 bars and a temperature of between 200 and 220° C. in the reactor;
• exposing the wood fragments introduced into said reactor to said steam for a time between 5 and 9 minutes and sufficient to obtain a steam cracking, a value of said exposure time and a value of the temperature of said substantially saturated steam being selected so that a severity factor is between 4.05 and 4.15, said severity factor being defined as:
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• where T is the temperature of steam in the reactor (expressed in degrees Celsius) and Δt is the exposure time in the reactor (expressed in minutes);
• continuously extracting from said reactor a same predetermined volume of wood fragments per minute, through at least one orifice opening into a conduit at substantially atmospheric pressure, so as to cause explosive decompression of said wood fragments extracted from said reactor in said conduit;
• and
• separating said decompressed wood fragments and the residual steam extracted from said reactor, said wood fragments obtained after separation forming said combustible material.