Breweries often use glycol-based refrigerants in fermentation tank cooling. However, glycol tends to flocculate and accumulate in the relief holes of the diaphragms of the solenoid valves normally used. This can lead to blockages and thus to undesirable switching problems.
Consistent and reproducible fermentation control is then no longer possible. To prevent this from happening at the Versuchs- und Lehranstalt für Brauerei in Berlin (VLB), Bürkert Fluid Control Systems has installed new process valves (type 8801) there. These valves are supplied with clean control air, which is channelled into the spring chamber and the control head after the switching process.
The resulting overpressure prevents moisture, cleaning agents and impurities from entering the interior. In addition, the pneumatically actuated spring adjustment system can simply crush any flocculation. This means that nothing can get stuck or clogged.
Conversion without great effort
With the new valves, the research and training centre prevents unexpected fluctuations in cooling, which could potentially be caused by the unexpected flocculation of glycol. This additional safety is of crucial importance for continuous production quality.
The VLB can now control the fermentation temperatures in its test brews even more precisely and reproducibly. The process valves impress with their compact and smooth design and are approved in accordance with Regulation (EC) No. 1935/2004 for materials that come into contact with food.
When retrofitting the fermentation tank cooling system, the existing control of the previous solenoid valves could be retained and no changes were necessary to the control system. Only the additional compressed air supply had to be ensured.
