Biomass & Bioenergy, Vol.70, 452-460, 2014
In-situ torrefaction and spherical pelletization of partially pre-torrefied hybrid poplar
A novel compacted, spherical, torrefied biomass pellet is discussed. Pellets were pressed in a heated mould and die, and torrefied in-situ (at 280 degrees C) from both untorrefied and pre-torrefied (at 250 degrees C) hybrid poplar sawdust prior to pelleting. Spherical pellets were successfully produced from both input materials. The calorific value of these pellets, referred to as "Q'Pellets", is 20.78 MJ kg(-1)-21.60 MJ kg(-1) on a moisture and ash free basis, which compares favourably with lignite coal. The ash content of Q'Pellets was as high as a mass fraction of 2.07%-5.08%. Q'Pellets are demonstrated to be uniquely durable, as they did not abrade in a tumbling can test or fracture in an impact resistance (drop) test. (C) 2014 Elsevier Ltd. All rights reserved.