Seasonal Extractive Variations in Trees, Chips and TMP and Their Impact on Paper Quality, 2007 International Mechanical Pulping Conference

Please Note: This document will be available in PDF format in the "My Electronic Documents" link on the home page once your order has been completed. Please make sure you have the latest version of Acrobat Reader. Click on the Acrobat Reader icon to check for the latest version, it’s FREE. To print a hardcopy of a PDF file correctly you must have a postscript printer. If you are not sure if your printer is a postscript printer please refer to your owner’s manual.



Many TMP mills observe seasonal variations in e.g. strength properties and energy efficiency. It is known that the content of carbo-hydrates as sugar and starch varies in the living tree during the year. It is also known that lipophilic extractives affect strength properties and possibly also refining efficiency. However, there are limited amount of data available regarding seasonal variations in lipophilic extractives from the living tree to pulp. In this project the content of extractives were measured in living trees, chips, and second stage pulp. During the same period data about pulp strength properties and electrical energy consumption were collected. This paper describes the first eight months of the project. Seasonal variations in extractive content were noted for water- acetone- and cyclohexane:acetone 9:1 soluble extractives. It is suggested that acetone soluble extractives might have different impact on the process depending on season.