Biochar production from low-quality wood

The use of renewable feedstock in the industry is a very important issue. One of the most promising types of renewable feedstock is wood biomass. However, its properties (low density, hygroscopicity, dispersion) complicate its commercial use without pretreatment. These negative properties have especially high influence on logistics of this feedstock. So, the development of a technology for transfer of wood biomass to more convenient form is relevant.

Proposed method of wood processing is based on process of pyrolysis - thermal decomposition of biomass without oxygen at temperature of 450-500°C. The main products of pyrolysis are bio-oil, biochar and gases.

Biochar is a high-carbon material with a wide application in many branches of industry. It is known that the properties of biochar depend on the wood species and the final temperature of pyrolysis. Laboratory studies with the use of wood and bark of birch, basswood and aspen were performed for determine the yield of biochar and its properties from different types of wood biomass. It was determined that yield of biochar from bark is from 9.4% (birch) to 27.7% (aspen) from wood - from 23.3% (aspen) to 25.8% (birch). The carbon content of biochar from bark is from 62.2% (basswood) to 73.6 (birch), biochar from wood is from 79.5% (aspen) to 85.5% (birch). Ash content is ranging from 1.6% (wood of basswood) to 14.2% (aspen bark).

Thus, it was determined that this method of thermal processing of wood biomass allows to obtain a carbon material of high quality from low-quality wood.