Bio-Remediation and Bio-Utilization of Pulping and Bleaching Waste Waters
Report No 1367/1/05
March 2005


Efforts are made by the pulp and paper industry to reduce the chloroorganic and chloride discharges by the substitution of chlorine-containing chemicals with other more environmentally friendly bleaching agents such as hydrogen peroxide, oxygen and ozone. In response to the environmental concerns and stringent emission standards, modifications of the production process at the pulping and bleaching stages have been developed that can reduce the levels of absorbable organic halogen and toxic effect of the pulping and bleaching waste waters. The bio-utilization of industrial waste waters in production of high-value products such as enzymes and the use of enzymes in bio-bleaching to reduce the chemical consumption of chlorine-based bleaching agents present new environmentally sound technologies that can significantly minimize the environmental impact of the pulp and paper industry.


Remediation of industrial waste waters from the pulp and paper industry was investigated using bleaching with enzymes, biomimetic systems (polyoxometalates) and microbial fermentation processes. The waste waters under study were derived from the pulping and bleaching stages of pulp production. Two industrial pulp types were examined for their bleachability with enzymes: hardwood soda-aq pulp and bagasse soda-aq pulp. Following enzymatic treatments, pulp properties such as brightness, viscosity, kappa number, etc. were determined according to the Standard Methods of the Technical Association of the Pulp and Paper Industry (TAPPI, Atlanta, USA). Most of the waste water analyses such as chemical oxygen demand, colour, solid content, etc. were carried out as described in the Standard Methods for Examination of Water and Waste Water (APHA, American Public Health Association, Washington, DC, USA). Fermentation experiments for enzyme production were carried out in shake flasks and bioreactors in batch and fed-batch cultures. Evaluation of cultivation conditions was based on the levels of xylanase activity produced. The efficiency of various approaches of waste water bioremediation was evaluated mainly based on the impact on chemical load, toxic effect, chloride content and chlorinated organic matter.  

Polyoxometalate-based waste water bioremediation
Xylanase-based waste water bioremediation
Bio-utilisation of waste water for xylanase production with the fungi Aspergillus oryzae and Aspergillus phoenicis