The United States Woodpulp Industry - Forest Products Laboratory ...

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Table 1—Active U.S. woodpulp mills, selected years 1920-83 Year Plants Mills Total Capacity Average per mill No. No. - - - - - - - Tons/day - - - - - - 1920 1 — 323 15,340 47 1930 1 1940 — 308 21,185 69 1 1950 — 259 29,840 115 1 1955 — 258 43,660 169 1 — 323 61,800 191 1961 277 350 89,560 256 1965 272 335 103,405 309 1970 278 336 132,735 395 1974 271 324 145,555 449 1983 254 315 173,855 552 1 lncludes idle mills and mills under construction. Sources: Lockwood Publishing Co., Inc. (1966, 1968, 1971, 1973) McKeever, David B. (1977) Miller Freeman Publications, Inc. (1983) U.S. Department of Agriculture, Forest Service (1961, 1965) Vance Publishing Corp. (1984) had the second largest combined capacity, at 22,000 tons per day or 13 percent of total U.S. capacity. No other mill type accounted for more than 10 percent of total capacity. All types have experienced steadily increasing average mill size. The U.S. woodpulp industry has responded rapidly to changing pulping technologies. This is evidenced by the trends in mill capacities and numbers of mills diverging for different grades of pulp (fig. 1, table A-1). Since 1920, some woodpulp grades have steadily declined in importance (soda); others have steadily increased in importance (sulfate), and new grades have been developed (thermomechanical). Soda mills, once larger and more numerous than sulfate, have declined in importance to the extent that soda mill data are now included with sulfate. Sulfite mills steadily declined in numbers while increasing total capacity through 1965. Since then, both numbers and capacity have declined. Much of this decline has resulted from direct competition from sulfate pulp, which can be produced more efficiently, and from the high costs of pollution control associated with the sulfite pulping process (American Paper Institute 1975, 1979; Guthrie 1972). Average sulfite mill size, however, is still increasing. Capacity and numbers of sulfate mills increased rapidly through 1970. Since then, numbers of mills have stabilized at approximately 120, while capacity continues to increase. Many factors contributed to the rapid increase in sulfate pulping capacity: the ability to use very resinous woods and many different tree species; higher yields than other chemical pulping processes; economically retrievable pulping by-products such as tall oil and turpentine; greater strength properties than other chemical pulps; and substitutability for sulfite pulp (Guthrie 1972). 2 The capacity of groundwood mills steadily increased. Although numbers declined through 1974, a large increase occurred between 1974 and 1983 with the adoption of the thermomechanical pulping process. Thermomechanical pulp, despite relatively high energy consumption for its production, is very attractive because of its high yield and substitutability for more costly chemical pulps (American Paper Institute 1981). Semichemical (including chemiground and chemimechanical) mills steadily decreased in numbers, but increased in capacity from 1961 through 1983 because of the increased use of hardwood pulpwood for which semichemical pulping is well suited (Guthrie 1972). Defibrated/exploded pulp mills, while maintaining fairly constant numbers, nearly doubled their capacity since 1961. Individual plant locations and capacities are listed in the appendix (table A-2). A map (fig. A-1) shows plant locations. Figure 1—Capacity of different types of woodpulp mills, 1920-83.
Regional Pulpmill Capacity Of the four regions (Northeast, North Central, South, and West, shown in fig. A-1), the South has the largest pulping capacity, with 147 active mills in 1983. These mills are capable of producing 114,000 tons per day, nearly two-thirds of U.S. capacity (fig. 2, table A-3). The West is the second largest regional capacity at 30,000 tons per day, 17 percent of U.S. capacity. Capacity in the Northeast is 16,000 tons (9 pct) and in the North Central region is 13,000 tons per day (8 pct). Southern mills are larger than those in other regions. Since 1920, mill capacity has increased in all regions. Trends in the number of mills, however, vary in different regions. In the South, the number of mills has increased from 24 to 147 between 1920 and 1983 (table A-3). In the West the number of mills increased from 1920 through 1970, peaking at 75 then dropping to 62 by 1983. The Northeast steadily lost mills, dropping from a high of 197 in 1920 to 48 in 1983. Numbers of North Central mills fluctuated widely, standing at 58 in 1983. The South is dominant in the woodpulp industry because its timber resources can support large sulfate pulping mills. The southern pines are highly resinous and thus ideally suited to the sulfate pulping process. Large volumes of both roundwood pulpwood and sawmill and plywood plant residues provide the large quantities of relatively inexpensive pulpwood needed by southern sulfate mills (Guthrie 1972). In 1983, 76 percent of all sulfate pulp capacity was in the South, accounting for 80 percent of the South’s total capacity. Much of the remaining sulfate capacity and over half the sulfite capacity is located in the West. Western softwoods such as fir, spruce, and hemlock are well suited to sulfite pulping because of their low resin content. The Northeast and North Central regions tend to produce pulp grades, such as semichemical, capable of using the abundant hardwood resource efficiently. Regional differences also reflect the installation dates and differing economies of scale between major pulping processes. Figure 2—Capacity of woodpulp mills in different regions, and total capacity 1920-83. 3
Page 1 and 2: United States Department of Agricul
Page 3: The United States Woodpulp Industry
Page 7 and 8: Pulpwood Consumption and Production
Page 9 and 10: Literature Cited American Paper Ins
Page 11 and 12: Table A-1—Number and capacity of
Page 13 and 14: Defibrated/ exploded Table A-2—Ca
Page 15 and 16: Semi- Defibrated/ chemical3 explode
Page 17 and 18: Table A-2—Capacity of individual
Page 19 and 20: Semi- Defibrated/ chemical3 explode
Page 23 and 24: Defibrated/ exploded Table A-2—Ca
Page 27 and 28: Defibrated/exploded (P/C) 3 Groundw
Page 29 and 30: Table A-6.—Annual U.S. production
Page 31: 2.0-2/87

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