In 1998, waste gas was 14 percent higher than in 1994--petroleum coke was 12 percent lower (NS) and blast furnace gas was 18 percent lower.

Of all byproducts, waste gas was 40 percent of all the byproducts used in 1998--36 percent share in 1994.

The petroleum industry uses more than half of the byproducts used as an energy source--most of the petroleum industry byproduct use was waste gas (1,399 trillion Btu in 1998).  

The chemical industry experienced the fastest growth in waste gas--267 trillion Btu in 1994 to 416 trillion Btu in 1998. 

In 1998, the paper industry used 29 percent of the byproducts--mainly pulping or black liquor and wood chips or bark--showing no growth in the use of byproducts since 1994.

Although only a small percent of all byproduct use, softwood veneer and plywood manufacturers doubled their use of wood chips or bark (58 trillion Btu in 1994 and 122 trillion Btu in 1998.