COFIRING OF WOOD CHIPS WITH COAL IN INTERIOR ALASKA

During 1984, 1986, and 1987, test burns of aspen (Populus tremuloides Michx.), paper birch (Betula papyriferia Marsh.), and white spruce (Picea glauca [Moench] Voss) wood chips mixed with coal were made at a local steam plant. Fuel mixtures tested ranged from 10 to 30 percent wood chips (wet weight basis). At the moisture contents and fuel proportions tested, the wood chips had no significant impact on particulate emissions. Harvesting operations producing only wood chips were estimated to achieve costs low enough that energy derived from burning wood chips would be competitive with energy derived from burning coal if more than 30,000 tons of wood chips were produced per year, and haul distances were less than 60 miles.