A New Representation for Low Consistency Refining Data

The standard method of representing refining data is to plot fibre or sheet properties as a function of refiner Specific Energy Consumption (SEC), for separate refining trials done at different Specifics EDG Loads (SEL). This approach does not allow for refining outcomes to be predicted when refining at other values of SEL and does not allow for refining conditions to be optimized to satisfy multiple constraints. In addition, the change in fibre properties is determined by the number of impacts on a fibre and the energy used in each impact, while SEC is the product of number and energy used in each impact. The paper describes a new representation of refining data where the two axes of the plot are SEC/SEL, which is proportional to the number of impacts, and 1/SEL, which is proportional to the inverse of the energy used in each impact. Data from refining trials are then plotted as lines of equal value. The paper shows how flow and power limited for a low consistency refiner are represented on such a plot. The utility of the approach is demonstrated with refining data of a CTMP pulp with three different refining plates and three different speeds.