CHARACTERIZATION OF MECHANICAL PULP FINES BY IMAGE-ANALYSIS

An image analysis method was developed and tested for characterizing m echanical pulp fines, The work was focused on finding a set of paramet ers to describe relevant properties of the fines and to test the funct ionality of the image analysis, In the method fines particles were cla ssified into fibrillar and nonfibrillar material. Laboratory handsheet s were prepared from the same fines and standard measurements of the s heets were used as a reference to evaluate the parameters provided by image analysis. Of the image-based parameters, the mass proportion of fibrillar material was found To be the most important factor for indic ating the properties of fines. An increase in the proportion of fibril lar material resulted in improved strength properties and sheet smooth ness, An increase in the proportion of fibrillar material is associate d with a decrease in the light scattering coefficient.