The future of beer filtration

After extensive development, the companies Westfalia Separator Food and Pall are now in a position to offer filter systems for continuous beer filtration with equal or even better quality results than conventional filter systems based on kieselguhr/ DE- filtration.

The solution is a high-efficiency separator for the removal of as many particles as possible prior to the second step – a low-flow filtration system based on cross-flow.

The separator is a specially designed system for this application with a patented hydrohermetic seal technology, gentle feed system and specially finished surfaces on all parts coming in contact with the product. This ensures high performance with excellent separation efficiency and at the same time gentle treatment of the colloids and yeast due to very low shear stress.

The separated solids are ejected, depending on their consistency, with a high dry substance content, hence reducing beer losses. Standard beer stabilising agents are separated from the beer by the high-efficiency separator prior to filtration. Stabilisation depends on the amount of stabiliser, reaction temperature and reaction time prior to separation. Different scenarios can be realised according to the existing process or necessities of the brewery. Stabilisation after filtration is possible with different techniques as well.

The second step in a PROFI system is a patented hollow fibre cross-flow system that is operated in a ‘dead-end’ mode. Because of the separation of virtually all particles, no retentate tank or recirculation line is necessary, which makes the system design, handling and control simple and reduces the losses drastically.

In addition, the consumption of water for evacuation of oxygen out of the system and cleaning is significantly lower than with conventional filter systems. The amount of water required for the cleaning cycles including wastewater is much lower as well.

Due to the patented design of the membrane modules with the independent Membrane Cleaning Unit (MCU), cleaning with standard caustic – without additives, at high temperatures up to 75-80°C – is now possible. That allows a cleaning procedure without enzymatic or aggressive cleaning agents. Additionally, only hydrogen peroxide and a surface-active membrane cleaner is dosed in during CIP.

After each cleaning cycle, an integrity test is carried out automatically (likewise patented) that makes the system highly reliable and makes the use of the process safer for the user than other systems. Because of the cluster-wise design of the membrane blocks (MBL), the filter plant is always able to filter beer even if one of the clusters of one block might not have passed the integrity test.

Many years of production with the PROFI system have shown that the beer produced is identical or, in many cases, even better than it is when produced with conventional or other systems. PROFI systems have been installed in breweries since 1995 for hourly filtration capacities of between 20-400hl/h. The basis for the design of the different plants has been piloting with fully automated plants that can be seen as small production units. After the piloting, the results have been used for a detailed scale-up.