Biogas Collection & Handling Specifications

EFI's standard biogas collection and handling system is rated at 82,700 cu ft/hr throughout — from the pressure/vacuum relief valve and sediment trap through the flame trap assembly and waste gas burner. Systems are sized based on actual biogas production and can use multiple parallel units for higher volumes.

The system maintains cover pressure between -0.5 and +0.4 inches water column. A Varec Model 5810 pressure/vacuum relief valve with 316 SS trim and flame arrester provides primary protection. A Varec Model 7100B explosion relief valve provides secondary protection. Blowers operate on PLC-controlled time cycles or pressure-based logic with adjustable high/low setpoints.

EFI uses Eldridge thermo mass gas flow meters with a range of 0 to 100,000 cu ft/hr and totalizer function. Thermal mass flow meters provide accurate biogas measurement without requiring pressure or temperature compensation, and have no moving parts for reliable long-term operation.

The Varec Model 244W waste gas burner has 82,700 cu ft/hr capacity with automatic electric ignition and propane pilot. The pilot operates only during waste gas flaring via a solenoid valve (fails open for safety). Pilot failure indication is displayed on the NEMA 4X control panel. During low-flow periods, one or two burners can be capped.

Daily checks include: verify P-traps are full and overflowing, confirm the flare is burning properly, check igniter operation, verify normal flow on the meter, ensure the cover is not inflated, and confirm the gas equipment enclosure gate is closed and locked. Quarterly maintenance includes cleaning flare burners, verifying burners are level, and checking refractory material position.