Investigation of Beer Filtration Using Cellulose Fibers in a Pilot-Scale Filter Plant

Due to the growing problems with diatomite, mainly concerning disposal and health issues, there is an increasing demand for alternatives. In particular, small- and medium-sized breweries need solutions that allow existing equipment to be retrofitted, such as clarifying filtration systems for beer using regenerable, highly pure α-cellulose fibers. To evaluate the filtration properties of currently available fibers, a series of trials was carried out on a pilot-scale horizontal filter plant. Laboratory methods using a filter tube and EBC filter were judged with respect to their ability to predict the filtration behavior of the filter aids and mixtures thereof. Specific resistance, which refers to the dry mass of the filter cake, was thoroughly observed. The retention capacity determined in a defined filter tube-based laboratory test was not sufficient to predict filtration behavior. During regeneration, fibers were mainly shortened and roughened, leading to higher selectivity but also to a shorter filter run time. The results were better than those previously reported, but it was not possible to achieve the filtered beer quality level of diatomite using a single-stage filtration, because the resulting turbidity levels were too high.