2714 Chapter 22 



and electricity at wood processing plants. Additionally, pulpmills used about 5 

 million tons, dry basis, of bark removed from roundwood pulpwood and 61 

 million tons of spent liquor solids for fuel. Wood processing plants in the future 

 are likely to use as fuel nearly all their bark and most of their wood byproducts 

 not sold for wood pulp or particleboard furnish. Should fossil fuel prices contin- 

 ue rising, some plants will bring in nearby forest residues, or urban residues, to 

 supplement mill fuels. Some mills will sell excess power to utility companies. 



Currently, a small amount of mill wood byproducts and bark is used for 

 producing heat or steam power at other manufacturing plants or at institutional or 

 commercial buildings. There is much interest in the possibility of increasing the 

 use of wood for such purposes — especially as an outlet for forest residues and 

 wood from cull trees, thinnings, and dead trees. It is difficult to predict the 

 eventual extent of such use. 



In 1978, wood and bark provided all or part of the fuel requirements of some 

 10 or 12 utility plants in the United States. The ultimate magnitude of fuel wood 

 use by steam-electric plants will depend on many factors, such as price trends for 

 coal and oil in comparison to fuelwood, practical aspects of developing assured 

 long-term fuelwood supplies, problems in collecting and storing very large 

 quantities of wood or bark, and advantages or disadvantages of the various fuels 

 in meeting emission control standards. The National Energy Act of 1978 pro- 

 vides incentives for cogeneration and use of fuels other than oil and gas in steam- 

 electric facilities. Because fuelwood requirements of even small steam electric 

 plants are very large, the potential impact of a single such installation on local 

 timber supply could be great. If many were developed, there would be major 

 impacts on timber resources, and especially hardwood resources, over large 

 areas. Projections of timber demand for steam-electric utilities cannot be pre- 

 dicted reliably because of indeterminate factors affecting such demand. 



Because the eastern hardwood resource is underutilized and is available from 

 private landholdings adjacent to large populations, this resource will be especial- 

 ly attractive for fuel. Harvesting, processing, and marketing of hardwood for 

 fuel are discussed elsewhere in this text, as follows (see also index under heading 

 Fuelwood): 



Subject Text reference 



Heat of combustion of wood and bark Table 9- 1 2 



Technology of burning and other processes for obtaining energy 



from wood Chapter 26 



Harvesting technology Chapter 16 



Moisture content of wood and bark Table 8-2 



Drying of chips Figures 20- 1 SAB 



Drying of roundwood and splitwood Figures 20-15 through 20-17 



Economics of — 



• Harvesting fuel chips Section 28-9 



• Harvesting forest residue in bale form Section 28-7 



• Operating a diesel tractor on wood gas Section 28-1 



• Hardwood pyrolysis Section 28-10 



• Wood charcoal production with a Herreshoff furnace Section 28-20 



• Hardwood gasification Section 28-6 



• Ethyl alcohol production (large scale) Section 28-33 



• Ethyl alcohol production (small scale) Section 28-5 



