Oxidative Torrefaction of Sunflower Husk Pellets in the Kaolin Layer

Abstract In this paper oxidative torrefaction of sunflower husk pellets in the kaolin layer was firstly investigated. Besides, influence of kaolin without use of special additives on limitation of the oxygen flow from environment into the sunflower husk was analyzed. Torrefaction temperature, torrefaction time, and height of kaolin layer over the range of 240–280°C, 30–60 min, and 3–5 cm, respectively were varied. Analysis showed that increase of temperature led to more significant influence of layer height on mass yield. Energy yield gradually decreased with increasing torrefaction temperature and torrefaction time, and height of kaolin layer had the opposite effect on the energy yield. With the increase of torrefaction intensity, drier fuel with higher hydrophobicity was formed. Torrefaction resulted to biomass destruction, although the fiber structure was retained.