Process Considerations and its demands on TMP property measurements – a study on tensile index
Olof Ferritsius, Rita Ferritsius, Jan Hill, Anders Karlström, Johanna Ferritsius and Karin Eriksson
As a vital component in the strive towards improved energy efficiency in the operation of TMP refining processes, this work highlights the importance of well- designed procedures when collecting and analysing pulp properties with respect to process conditions. Process data and pulp from a CD82 chip refiner have been used to show that tensile index has strong co-variance with fibre residence time calculated by the extended entropy model. A combination of theoretical and practical analysis methods has shown that, in order to assure representative, reliable results, pulp sampling procedures should comprise composite pulp samples collected during a sampling period of about three minutes. In addition, at least four subsequently collected composite pulp samples should be included in the analysis to effectively dampen effects from fast process variations as well as from slow process drift. An in-depth study on tensile index measurements clarifies that 40-60 strips should be used in the case we studied regardless if machine made paper or handsheets are considered.
Nordic Pulp & Paper Research Journal (NPPRJ) is an international scientific magazine covering science and technology for the areas of wood or bio-mass constituents, pulp and paper and including new fiber-based materials, recovery and by-products from pulping processes, bio-refining and energy issues. Articles meeting required scientific standards are accepted from any continent. Open Access: Articles not available through Gold Open Access may be purchased by credit card as a pdf file, to be downloaded within 24 h after ordering, at a price of 22 EUR per article. (Value added tax may apply depending on your location, which you enter at payment logout.) Such articles have Green Open Access, i.e. authors may share articles on their personal non-commerical homepage immediately after publication on the website and download them to non-commercial hosting platforms one year after publication in a full issue of NPPRJ. ISSN: 0283-2631