Forest productivity

R. Kat2en Associates, Chemicals from Wood Wastes, U.S. Department of Agriculture Forest Products Laboratory, Madison, Wise., Dec. 14,1975. 

National Design Specificationsfor Wood Construction, National Forest Products Association, Washington, D.C., 1977. 

Wastes or By-products as Raw Materials. By far the largest volume of natural products for industrial use, aside from the forest products, are wastes or by-products of food processing (qv). The largest use of these wastes is as animal feeds. Because they are used rather than becoming a disposal problem, they are considered to be chemurgic products. 

Grain that is usable as food or feed is an expensive substrate for this fermentation process. A cheaper substrate might be some source of cellulose such as wood or agricultural waste. This, however, requires hydrolysis of cellulose to yield glucose. Such a process was used in Germany during World War II to produce yeast as a protein substitute. Another process for the hydrolysis of wood, developed by the U.S. Forest Products Laboratory, Madison, Wisconsin, uses mineral acid as a catalyst. This hydrolysis industry is very large in the former Soviet Union but it is not commercial elsewhere. 

More recently, interest has developed in the use of enzymes to catalyze the hydrolysis of cellulose to glucose (25—27). Domestic or forest product wastes can be used to produce the fermentation substrate. Whereas there has been much research on alcohol fermentation, whether from cereal grains, molasses, or wood hydrolysis, the commercial practice of this technology is primarily for the industrial alcohol and beverage alcohol industries. About 100 plants have been built for fuel ethanol from com, but only a few continue to operate (28). 

The agricultural and forest products industries are dependent on renewable resources for their existence. They are also acutely aware that air pollution can damage vegetation and, therefore, threaten their existence. Both industries have been exempt from many air pollution regulations in the past, but now they are finding these exemptions questioned and in some cases withdrawn (15). 

The forest products industry encompasses a broad spectrum of operations which range from the raismg of trees, through cutting and removing the timber, to complete utilization of the wood residue (17). 

Driers are used in the forest products industry to lower the moisture content of the wood product being processed. Drying of dimension lumber gives it dimensional stability. This type of drying is done in steam kilns and is a batch process. No appreciable pollutants are released. 

Carlson, F.E., Phillips, E.K., Tenhaeff, S.C. and Detlefsen, W.D., Measuring and Controlling Volatile Organic Compound and Paniculate Emissions from Wood Processing Operations and Wood-Based Products. Forest Products Society, Madison WI, 1995, pp. 52-61. 

Higuchi, M., Morita, M., Urakawa, T, Yoshimalu, T. and Kamo, N., Adhesives 2000 Symposium. Lake Tahoe, NV, Forest Products Soc., in press. 

Fig. 3. Wedge test crack length as a function of maximum Cu buildup at the oxide-metal interface. The adhesive was Cytec FM-123. The surfaces were prepared with the Forest Products Laboratory etch. The oxide morphology was kept constant. Data are from Ref. 115].

Ellis, S. and Steiner, P.R., In Wood Adhesives 1990, Proceedings, Forest Products Society, Madison, WI, 1990, p. 76-85. 

RiedI, B. and Park, B.-D., In Wood Adhesion Research, Proceedings, Forest Products Society, Merida, MX, 1998, pp. 115-121. 

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