Optimised & User-Friendly Solutions

BioSecure Positive and Negative Pressure
protection

Why pressure safety is essential in a biogas plant

BioSecure is the overpressure and underpressure safety device from Biogastechnik Süd, developed to provide reliable protection for digesters and gas storage tanks in biogas plants. If the gas pressure in the storage tank rises above the permissible limit, the overpressure safety device prevents damage to the membrane and the tank. If the pressure falls below the minimum value, the underpressure safety device protects against vacuum damage. BioSecure complies with the relevant standards and is therefore a mandatory component for the safe, compliant operation of biogas plants.

The Biosecure overpressure and underpressure safety device can be activated either mechanically via a biogas storage membrane or via weight-loaded float chambers. The Biosecure housing is made of stainless steel, whilst the float cups and the linkage are made of plastic. We use water as the containment fluid, which is supplemented with antifreeze at low outside temperatures. An insulating jacket or an electric heating element can be fitted as an option to prevent the water from freezing without the need for antifreeze. The built-in sight glass allows the internal operation of the housing to be checked.

Overpressure and Underpressure Protection: How it Works

The Biosecure overpressure and underpressure safety device monitors and regulates overpressure and underpressure in the fermentation tanks of biogas plants. It protects the biogas storage membranes of fermenters, secondary digesters and digestate storage tanks from excessive loads.
The Biosecure has been designed as a safety component within the meaning of the Machinery Directive 2006/42/EC.

However, the level of safety we aim to achieve when operating a biogas plant can only be attained in practical operation if all necessary measures are taken. It is the operator’s duty of care to ensure that these measures are implemented and to monitor their execution.

Advantages

Biosecure

Reliable over- and under-pressure protection: available either as a pneumatic system (under- and over-pressure) or with mechanical control (e.g. gas bag)
When used in conjunction with the insulating jacket, no antifreeze is required as a barrier fluid down to – 20 °C.
No topping up of the barrier fluid is required
Liquid levels regulate themselves
Excess condensate drains into the fermentation tank
Maintenance-free
A heating element can also be fitted as an option
Includes a pressure test connection
Includes a connection for a pressure sensor