Focused beam reflectant measurement as a tool to measure flocculation

This paper presents several uses of focused beam reflectance measurement (FBRM) as tool to measure flocculation. It includes information on the interaction of wet-end aids with the different pulp fractions, such as optimal polymer dosage and the resulting floc properties (floc size, strength, etc.). The study of the floc evolution over time under different conditions also allows us to identify flocculation mechanisms. The FBRM methodology provided a real-time, in-process monitor to establish the evolution of the resulting flocculation state and polymer efficiency under the influence of shear forces. The evaluation included a study of deflocculation and reflocculation processes occurring in the sample. We also looked at the problem of contaminants accumulation, as can occur with increased use of recovered paper and the closure of water systems. In addition, FBRM has been used to identify dissolved and colloidal material agglomeration and to study its influence on polymer demand for a given furnish.