Residuals in Manufacture of Paper

The manufacturer of pulp and paper results in the generation of residuals in gaseous, liquid, and solid forms. The major sources of each type of residual are identified and quantities generated in the production of a typical product are tabulated. The influence of raw material, pulping and bleaching processes, product characteristics, and other production factors is indicated. Methods for reducing discharge of residuals are classified and described, including by-product production, process changes involving partially offsetting cost advantages, and end-of-pipe waste treatment. Application of these methods to change the quantity or form of one residual usually affects one or more other residuals. Examples of the extent of modification required to meet discharge standards for residuals are included for a 500-ton-per-day integrated mill producing tissue paper.