Pressure regulation in beer fermentation and maturation tanks
Atmospheric tanks
Tanks, designed for use at atmospheric pressure, are equipped with a vent valve, which is installed on the lid. The purpose of the vent valve is to prevent overpressure and vacuum inside the tank.
Pressure tanks
Pressure tanks must be manufactured in accordance with strict standards and guidelines for the manufacture of devices, operating under an increased pressure load. The dimensions, sheet metal thickness, and all installed components and accessories must meet the requirements of the pressure tank calculations. Each pressure tank must be equipped with a suitable safety mechanism, which is triggered if the pressure inside the tank exceeds the indicated limits.
In order to enable pressure regulation, pressure tanks are equipped with:
Vacuum/pressure relief valve
The pressure tank is equipped with a relief valve, which is installed on the lid. This valve is used to prevent overpressure and vacuum inside the tank.
Operation: When the pressure inside the tank reaches the maximum allowable value, the valve opens and releases the excess air from the tank. When the pressure value returns within the allowed range, the valve closes again. The valve also opens if a vacuum is created inside the tank. When the pressure value is once again within the safe range, the valve closes again.
Safety valve
Each pressure tank also needs a safety valve, which is triggered if the pressure value inside the tank becomes dangerously high; this can occur due to a malfunction or if the vacuum/pressure relief valve is not effective enough.
Bunging device (spundapparat)
The bunging device (spundapparat) has a dual function. It enables precise pressure control inside the tank and also works as a safety valve, protecting the tank against overpressure and negative pressure (vacuum). The bunging device is usually mounted on the tank's CIP tube. It is a standard piece of equipment of our LTI and ZKI series pressure tanks, which are designed for beer storage and maturation. It is also available as an option for the ZMI series cylindroconical pressure tanks.
Operation: Set the desired tank pressure (e.g. 0.5 bar) and fill the bunging device container with water. When the pressure inside the tank exceeds the set value, the valve opens and releases the excess air from the tank. Bubbles form in the water container. This way, this particular safety device also serves as an indicator of fermentation intensity.
