Pulp and paper mills use large quantities of water during the production process. Source waters include both ground and surface and vary in quality. Raw water treatment is required to remove or control impurities that may adversely affect product quality or increase maintenance costs.

Replacement of chlorine by chlorine dioxide in pulp bleaching solves many of the environmental problems facing modern paper mills, as many of the toxic species, such as dioxins and furans, which appear in the plant effluent are reduced to below a detectable level when chlorine dioxide is used.