Utilization of carbon produced by torrefaction of grass for energy purposes and related risks

Nine species of perennial grasses were studied as a possible raw material for energy production. Torrefaction at 200 degrees Celsius was used for production of biochar. Values of H/C ratio in individual species were determined in order to estimate the degree of thermal transformation. The attention was paid to the influence of inorganic components on the slagging and fouling. The water leaching was tested as a mean for decreasing the content of alkalies. Mineral phases present in biochar were determined by X-ray diffraction. The torrefaction process appears to be suitable for preparation of relatively high-quality fuel from grass. The content of risk alkalies can be minimized by water leaching.