Opportunities to use bark polyphenols in specialty chemical markets

Abstract

Current forestry practice in North America is to transport pulpwood and logs from the harvest site to the mill with the bark on the wood. Approximately 18 percent of the weight of logs from conifers such as southern pine is bark. The majority of this bark is burned as hog fuel, but its fuel value is low. When compared with natural gas at an average of $2.50/MBTU or electricity at 3.5 cents/KWH, burning wet bark has a gross fuel value of about 1.2 cents/lb on a dry weight basis. Considering the cost of transport, as well as the capital and maintenance costs of boilers, processing bark for fuel is a costly business and seems to be practiced only to avoid a large solid waste management problem. One must not lose sight of the fact that one must handle nearly two lbs of wet bark to recover that 1.2 cents. In addition, concerns about air quality, especially increasingly stringent limits on particulate emissions, has stressed the ability of hog fuel boilers to meet regulatory requirements. The author explores options for producing higher value products from bark.

Citation

Hemingway, Richard W. 1998. Opportunities to use bark polyphenols in specialty chemical markets. Proceedings, 2nd biennial residual wood conference; 1997 November 4-5; Richmond, BC. Richmond, BC: MCTI Communications, Inc.: 80-85.