BIOCOAL IN MINUTES –BIOMASS STEAM PROCESSING ON THE PILOT PLAN SCALE

摘要

The use of steam to carbonize biomass has been tested in a laboratory screw reactor at atmosphericpressure and at temperatures between 250 and 400°C for short reaction times between 30 and 150 minutes. Thistreatment has been named biomass steam processing (BSP). The resulting biocoal is compared with products ofhydrothermal carbonization (HTC) of biomass in liquid, pressurized water at typical HTC reaction parameters i.e.180 to 240°C, 15 to 33 bar, 0.5 to 12 hours. BSP derived biocoal was found to be very similar to HTC coal product interms of elemental composition and higher heating value (HHV). Hence, BSP is thought to be an effective alternativeto HTC having much less elaborate process parameters, especially atmospheric pressure and shorter reaction times. Inthe present study, the process parameters obtained at laboratory scale with a maximum throughput of 0.5 kg·h~(-1) aretransferred to a BSP pilot plant with a maximum throughput of 50 kg·h~(-1).