Biogas plants use compressed air for digester mixing, biological desulphurisation, and the control systems that keep gas production stable. The air system must be reliable, oil-free and safe in a potentially explosive atmosphere.
Key applications
- Digester agitation with air or biogas
- Micro-aeration for desulphurisation
- Instrument and valve actuation
- Blower assist and flare systems
Safety
Where air mixes with methane, the equipment and controls must suit the hazardous area classification. Oxygen dosing for desulphurisation is precisely controlled, and backflow protection stops biogas entering the air system.
System design
Use oil-free compression with drying and filtration, and separate instrument air from process air. Redundancy and continuous monitoring keep the plant running, because a loss of control air can stop gas production and flaring.