Bleaching

The main objective of bleaching is to produce a brighter pulp. This is accomplished in chemical pulps primarily through lignin removal. The removal of other compounds is another objective of the bleaching process. These compounds include resins, fatty acids, and other extractives.

For many years the PDC has worked closely with the pulp and paper industry to develop new and effective bleaching sequences. We can perform a wide range of bleaching sequences on mechanical, recycled, and chemical pulps. The sequences may be comprised of a variety of stages, including chelation, enzyme, oxygen, ozone, chlorine, chlorine dioxide, extraction, and hydrogen peroxide stages.

  • Medium-Consistency Oxygen Reactor (around 400 grams/batch)
  • Quantum Reactor
  • Laboratory Bag Bleaching Apparatus (Cl2, ClO2, H2O2, E stage, H, FAS, etc.)
  • Ozone Generator and Reactor (around 30 grams/batch)
  • 100% ClO2 Generator Reactor
  • Stainless Steel Handsheet Setup
  • Residuals and pH
  • Chemical Oxygen Demand (COD)
  • Biological Oxygen Demand (BOD)
  • Total Dissolved Solids (TDS)
  • Color
  • Oxygen delignification of hardwood and softwood pulps
  • Optimization and kinetics of oxygen delignification
  • Evaluation of effects of pulping on bleachability
  • ECF and TCF bleaching of hardwood and softwood pulps
  • Bleaching of mechanical and secondary fibers

To learn more or begin working with us, contact us!