Abstract
Woody biomass is a hopeful energy resource to reduce greenhouse gas emission, and it is widely used in north Europe. Little amount of woody biomass is utilized for energy production, although Japan has much forest. Because most forests in Japan are located in steep mountain ranges. If woody biomass can be changed to high energy density fuel, the transportability of fuel will be improved, and the woody biomass will be potentially introduced in Japan. The purpose of our study is to improve the calorific density of cellulose by hot-press method, and to produce the semi-carbonized pellets. Cellulose is a main component of woody biomass. The cellulose is gradually dehydrated during the carbonization. The organic volatiles, however, are lost at the same time, and the energy yield of the carbonized cellulose is decreased. Therefore, the semi-carbonizing conditions, at which maximum energy yield can be achieved, should be investigated. In addition, the semi-carbonized pellet considerably contains tar in it. It is good for long storage because the tar becomes an antiseptic. This study examined to find the optimum condition of semi-carbonization for a preparation of pellet fuel.
