Trends in pulp and paper mill emissions of SO2 and NOx, 1980-2010

Abstract

Sulfur dioxide (SO2) and oxides of nitrogen (NOx) emissions from U.S. pulp and paper mills have been estimated from industry-wide surveys conducted every five years, beginning in 1980 and continuing through 2010. Between 1980 and 2010, total SO2 emissions declined by over 70%, while paper and paperboard production rose 35%. NOx emissions peaked in 1995, but fell by almost 40% over the next 15 years. Paper and paperboard production only declined 7% over the same period. These downward emission trends resulted from several factors, including reductions in oil and coal use, declining oil and coal sulfur content, increased use of add-on SO2 and NOx control systems on boilers, growing use of combustion modification techniques to minimize emissions, improvements in energy efficiency, and declining pulp, paper, and paperboard production over the past 15 years.