Change in humidity of solid biofuels

Abstract

Humidity, as one of the most important physical properties of pressed solid biofuels, affects thel calorific value of the biofuel and its consistency. Biofuel humidity depends on the initial humidity of raw material, which varies and depends on many factors. Method of manufacture and place and duration of storage have a considerable effect on solid biofuel humidity as well. Humidity of pressed solid biofuels changes not only during the pressing itself, when temperature increases by compression and a part of contained moisture evaporates, but also in the course of handling and storage under unstable environment conditions with high relative air humidity, when, on the contrary, their humidity gradually increases due to their hygroscopicity. Properties of solid biofuels change with their increasing humidity – their calorific value and consistency decreasing and the share of crumbles increasing.