Influence of Chip Pre-treatments on the Reduction of Extractives Content in High Yield Pulping of Jack Pine, 1999 International Mechanical Pulping Conference Proceedings

Robert Lanouette & Kwei-Nam (Ken) Law

Pulp and Paper Research Centre

Jacques L.Valade

Chemical Engineering Department

Université du Québec à Trois-Rivières

The utilization of jack pine (Pinus banksiana Lamb.) in the pulp and paper industry for the production of high yield pulps encounters some important problems such as high extractives content, high specific energy consumption and low optical and strength properties of the resulting pulps. This paper describes the effect of an extraction stage prior to a two-stage AP-TMP. By removing part of the extractives in an early stage of the process, it is expected to improve the development of the surface properties of fibres, to reduce the extractives content of the resulting pulp, and more importantly to obtain a final brightness suitable for the bleaching chemical levels used. Various chemicals, such as water, methanol, H2O2, NaOH, Na2SO3 or a combination of them, were tested in the extraction step. The results clearly show the potential use of jack pine in producing a high yield commercial pulp comparable in quality to the pulps presently available on the market.