3084 Chapter 25 



In recent years, use of hardwood for pulp and paper increased 2.5 times as fast 

 as that of softwood. In 1978 about 25 percent of the pulpwood used by southern 

 pulpmills was hardwood; this hardwood pulpwood yielded more than 25 percent 

 of pulp production because hardwood yields more pulp than softwood in full 

 chemical processes and also hardwoods are more used than softwoods in high- 

 yield pulping processes. 



TRENDS 



Consumption of hardwood pulpwood. — Hart (1980), discussing the poten- 

 tial for expanded use of hardwoods for pulp and paper, noted that usage of 

 hardwood pulpwood in eastern mills of the United States increased 6-fold (6.6 

 percent annual rate) between 1950 and 1978, compared to a less than three-fold 

 increase (4.2 percent annual rate) for softwood (table 25-3). Since 1970, the 

 increase in hardwood usage has slowed, however. 



Major users of hardwood pulpwood in the United States are mills making 

 bleached and unbleached sulfate pulp, and semichemical pulp (table 25-4). Only 

 mills producing groundwood pulps used less hardwood in 1977 than in 1963. 

 Application of press drying (Setterholm 1979) could significantly accelerate 

 usage of hardwood pulps made by the kraft process for use in linerboards; the 

 press drying process significantly increases strength and stiffness of hardwood 

 pulps (see section 25-4). 



Table 25-3. — Hardwood and softwood annual pulpwood consumption for the eastern 

 United States, 1950-1978 (Hart 1980)' 



Year Total Hardwoods Softwoods 



1950 

 1955 

 1960 

 1965 

 1970 

 1975 

 1978 



'Based on data from the American Paper Institute. 



