Torrefied Cogon grass: Effects of torrefaction on fuel properties of solid and condensate products

Abstract

Torrefaction is a thermal pretreatment process used to produce solid fuel by heating biomass below 300°C under anoxic conditions. This pretreatment process improves the fuel characteristics of Cogon grass, and its energy density was comparable to that of sub-bituminous class B and C coals. Sun-dried Cogon grass was torrefied in a fabricated batch torrefaction reactor, and their solid and organic condensate products were analyzed. A response surface methodology was used to examine the effects of the torrefaction reaction temperature, feed size, reaction time, and Cogon grass parts (CPs) on energy density, mass yield, and energy yield of the solid products as well as the effects of reaction temperature and reaction time on the energy density and mass yield of the organic condensate. The mass yield decreases as the reaction temperature is increased, whereas it increases as the feed shifts from leaves to nodes, from 54% at 250°C to 43% at 285°C and 39% using leaves to 60% using nodes. The energy yield increases from 50% to 82% as the feed shifts from leaves to nodes. This is, however, compensated by an increase of energy density by 34%. In addition, the energy density of the condensed gas products can be predicted using the four process parameters as an input variable on the surface response model for the energy density of condensed organic volatiles.

Application of Cogon Grass (Imperata cylindrica) as Biosorbent in Diesel-Filter System for Oil Spill Removal

“…It can be found on every continent. It grows to a height of 30 to 150 cm and is widely distributed across Asia and the North America, where it has been reported as infesting [17,18]. The grass covers more than 50% of forest land areas throughout moist tropical regions.…”