Rule of thumb for simulating biomass pyrolysis in packed bed reactor

Compared to other countries, Japan is particularly rich in forests; the percentage of Japan's landmass that is forested is 67%, which is the third highest in the world. Only 20% of all wood is effectively utilized as timber; the rest, including waste wood (4 million tons/year) and natural forests (10 million tons/year), is unused. In recent years, there has been increasing demand for quickly produced, environment-friendly energy resources; in particular, there is wide interest in the production of energy from woody biomass, using wood resources which are currently underutilized. The use of biomass to provide energy has many merits: it is renewable, abundant, easy to store, and carbon-neutral. As Japan has many mountains with steep slopes, it is difficult to transport the felled trees. So that, the development of a compact gasifier of high quality, which can cope with variations both in the amount of biomass collected and in energy demand, is necessary. Furthermore, in order to ensure that the system is used in the most efficient manner, it is necessary to increase our understanding of the reaction mechanisms involved in both decomposition of biomass and heat transfer in the biomass layer.