Production of fuel pellets, involves extruding undried starting material containing a binder, e.g. thermoplastic biopolymer, and a combustible material, e.g. wood chips, and removing liquid before discharge

摘要

A method for the production of fuel pellets by extruding a starting material containing binder components and/or raw material components, in which extrusion comprises compounding the extrusion material, mobilising the liquid in the starting material, extruding the material as continuous rope(s) and removing the liquid before discharging the material. Independent claims are included for (1) a composition containing a thermoplastic biopolymer and a combustible raw material for the production of fuel pellets, in which the content of biopolymer is at least 10 wt.% (2) an extruder system for the above method, comprising a cylindrical casing (10) containing two or at least one rotating extruder screw(s) (20), an inlet zone (42), several successive sections and an extrusion end-piece (50), in which at least one of the sections (30a-c) has at least one degassing opening with a suitable diameter and geometry in the casing (10), arranged so as to allow the egress of water or steam from the extrusion material while retaining this material largely within the casing (10) .