The raw biomass size for this reactor should smaller than 10 mm. In addition, raw biomass with very low bulk density and high moisture content is not suitable for this reactor. Because of the quality of torrefied biomass depend on the screw diameter, thus, it is difficult to scale up this reactor [22]. Energy research centre of the Netherlands (ECN) designed and constructed this reactor in 2008s.It had product capacity of 60-100 kg/hr with operating temperature of 220-280 ̊C [24].