Mixing conditions of slurries: Influence on the filtration operation

The study deals with the influence of the dispersion or mixing process on slurry filtration. A filtration trial pilot was realized for this investigation, to assure slurry dispersion and to measure pressure drops and flow rates through the filters, under industrial conditions. The flow of talc slurries through an industrial slot filter was studied under different dispersion conditions, the dispersion time and diameter of turbines being the main variables. The theological properties of a slurry dispersed in suitable conditions show a behaviour related to the presence of mineral charge aggregates, which could generate runnability problems during the coating operation and thus alter paper's quality. The final conclusion of the study is that the filtration operation depends on the mixing conditions, while the pressure drop through the filter may be related to the net dispersion energy and power number.