Part of a Series
Historically, most pulp and paper mills used elemental chlorine gas, but few do so today. Alternatives are available that eliminate or reduce toxic gas hazards. A few U.S. mills use totally chlorine-free bleaching, which employs an oxygen-based process with ozone or hydrogen peroxide. Many more U.S. mills use elemental chlorine free bleaching, which employs chlorine dioxide. However, like elemental chlorine gas, chlorine dioxide poses significant dangers of a toxic gas release to workers and communities. These mills can nonetheless reduce the danger of a toxic gas release by using up chlorine dioxide with minimal accumulation or storage.
One paper mill, Shweitzer-Mauduit of Spotswood, N.J., recently converted its bleaching process from chlorine gas delivered by rail to chlorine dioxide generated as needed without bulk storage from a premix solution. This change eliminated a chlorine gas vulnerability zone that included more than a million people. Because Shweitzer-Mauduit is a smaller mill, it can use a premix to generate chlorine dioxide without posing the danger of an off-site gas release. Larger mills usually have their own chemical facilities to produce chlorine dioxide, and can also reduce dangers by minimizing run-time storage.
For more on this topic, please see:
- Chemical Security 101 by Paul Orum and Reece Rushing