Anthraquinone and Anthraquinone Polysulfide Pulping for Extended Digester Delignification, 1993 Pulping Conference Proceedings
The need for cost-effective strategies for reduction of Kappa Number is of paramount importance for bleached kraft mills in order to develop economically sound strategies to meet pending EPA effluent guidelines. Several approaches for Kappa Number reduction have been examined including anthraquinone/polysulfide pulping in the digester, use of oxygen after batch digesters, and conversion of Kamyr digesters to modified continuous cooking. Material balances were constructed for a base case. The adoption of the three alternative strategies were compared to the base case for extended delignification. Economic models were developed and analyzed using conventional return on investment calculations and the modern method of free cash flow analysis. The analyses showed that anthraquione/polysulfide pulping has economic and strategic advantages over the other approaches.
Anthraquinone and Anthraquinone Polysulfide Pulping for Extended Digester Delignification, 1993 Pulp
