Chemical bleaching effluents, toxicity

Yeber, M.C. Rodriguez, J. Baeza, J. Freer, J. Zaror, C. Duran, N. Mansilla, H.D. Toxicity abatment and biodegradability enhancement of pulp mill bleaching effluent by advanced chemical oxidation. Water Sci. Technol. 1999, 40 (11-12), 337-342. 

It is often possible to use different process chemicals to accomplish the same goal. For example, both zinc hydrosulfite and sodium hydrosulfite can be used to bleach mechanical pulps. The substitution of the use of sodium hydrosulfite for zinc hydrosulfite was prompted, at least in part, by the establishment of effluent limitations controlling the discharge of zinc. Other opportunities exist to minimize the discharge of toxic and nonconventional pollutants through chemical substitution. 

WASTE DISPOSAL METHOD All decontaminated material should be collected, contained and chemically decontaminated or thermally decomposed in an EPA approved incinerator, which will filter or scrub toxic by-products from effluent air before discharge to the atmosphere. Any contaminated protective clothing should be decontaminated using HTH or bleach and analyzed to assure it is free of detectable contamination (3X) level. The clothing should then be sealed in plastic bags inside properly labeled drums and held for shipment back to the DA issue point. Decontamination of waste or excess material shall be accomplished in accordance with the procedures outlined above with the following exception ... 

The conversion of wood to fiber produces hundreds of chemical compounds that are discharged as effluents into surface water. Processes that use chlorine to bleach pulp produce substantial quantities of toxic chlorinated organic compounds, including dioxins and furans, compounds that attack the respiratory, musculoskeletal, reproductive, and CNS, skin, liver, and kidneys. These compounds are considered human carcinogens. 

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