Knowledge Base

Membrane biogas upgrading is the technology used by HoSt Bioenergy Systems and its sister company Bright Renewables. After pre-treatment to remove moisture and H₂S, the cleaned biogas is compressed and passed through a three-stage membrane system. The membranes allow CO₂ to pass through more readily than methane, separating the two gases by pressure difference. A recirculation loop between stages ensures minimal methane loss, with a methane slip of 0.5% or less and an overall methane recovery of 99.5% or higher. The system is fully automated, energy-efficient, and suited to a wide range of plant capacities. The biogas upgrading unit can be combined with a CO₂ Liquefaction unit. The methane will then be transferred back into the system, making the methane slip virtually 0%.

The CO₂ separated during upgrading is not wasted. It can be captured and liquefied to produce food-grade bio-CO₂, which is then used in the food and beverage industry, in greenhouse horticulture, or for industrial applications.