Refining of softened TMP fibres ‑ part 2

Project leader
Birgitta Engberg, MIUN

Project group
Hans Höglund, MIUN
Gunilla Pettersson, MIUN
Dino Muhic, Valmet
Anders Persson, Valmet
Tomas Sahlin, Valmet

Refining of Softened TMP Fibres
The purpose of refiner segment design is to introduce forces to the pulp and to transport the three phase mixture of steam, water, and fibre material to the discharge. However, the design also affects the refining gap – e.g. how small the gap can be during stable refining.

Most of the proposed ways to reduce energy consumption, e.g. by softening the wood material through chemical pre-treatment, mechanical pre-treatment or high temperature refining involves refining at a smaller plate gap. This is true also for LC-refining and increased production rate.

The project objective is to develop new refining technology for a reduction in energy consumption of at least 400 kWh/ton, compared with today’s BAT in commercial TMP-producing installations for printing paper grades. This will be done through developing a plate design that will be able to efficiently treat softened wood fibres in a much smaller gap than is normally used.