Pinch valves from the VMC series with flange connections from AKO Armaturen are used in the brewery to control diatomaceous earth for beer filtration. The DN 80 and DN 100 valves control the diatomaceous earth from its delivery and storage in the silos through to the actual filtering system.
Diatomaceous earth (also called kieselgur, diatomite or celite) is used at the end of the brewing process to filter out yeast cells and other particles and sediment that cause cloudiness.
In the deep-bed filtration process, diatomaceous earth is mixed with water and placed onto cellulose cloths – creating the so-called filter cakes through which the beer flows. To ensure that the filtered substances do not cause the filter cakes to stick together completely, additional diatomaceous earth is added on a regular basis to form new filtering layers and thus ensure that the beer can flow through unhindered.
The tasks performed by the pinch valves from AKO already start with the delivery of the diatomaceous earth. A vacuum pipeline is used to suck the delivered diatomaceous earth out of the silo tankers and move it to large stationary silos. AKO pinch valves with flange connections then ensure that it is smoothly distributed to the individual filtering systems. The food-grade sleeves fitted inside the valves are subjected to different stresses and strains at this stage. Some valves are operated with around 15 opening and closing cycles per day, while others are only used for around 20 cycles per week.
As the brewery operates around the clock, seven days a week, it was particularly important for the operator that the pinch valves from AKO Armaturen added to the brewing system were reliable and durable components. AKO was able to satisfy these requirements due to the simple design of the pinch valves consisting of just three components, the easy and quick maintenance and the in-place cleaning and sterilisation possibilities.
In order to keep the valves closed in the event of a loss of compressed air, additional safety arrangements (protection circuits) were integrated into the system that prevent the pinch valves opening even in the absence of a compressed air supply. In this case, the safety arrangements (protection circuits) were not fitted directly to the pinch valves but rather collected together and controlled centrally.
The operator of the system is very pleased with the pinch valves from AKO Armaturen. The valves stand out due to their fast opening and closing times and constriction-free flow characteristics. In addition, the risk of a blockage within the valve has also been minimised by using pinch valves (in comparison to commonly used types of valve such as butterfly valves or knife gate valves).
(filtering aid in beer filtration)
Opening and closing cycles:
Depending on the valve:
Between 15x per day - 20x per week
Plant operates around the clock (24/7)
Vacuum (500 mbar)
Horizontal & vertical
Nominal size: DN 80 & DN 100
Housing: Stainless steel 1.4408
Connections: Flange connection, stainless steel 1.4404 / AISI 316L
Sleeve: Natural rubber, food grade quality, light
Global market leader
Unique delivery promise
Widest pinch valve product range
Extensive service activities