Our biogas to biomethane membrane technology

For the upgrading of biogas to biomethane with the desired methane content, Bright Renewables applies the proven membrane technology capable of achieving more than 97% operational availability. How it works? Watch the video and learn in 3 minutes or keep on reading.

Separation by membranes

Bright’s biogas upgraders are compact and modular and contain a membrane unit. In this membrane technology unit, the gas is separated by means of an imposed pressure difference over the membrane. Two gas streams will be obtained from the plant; a product gas with a high methane value and a CO2 rich gas. Using membranes with high separation efficiency allows recovery of the highest possible methane yield. Depending on the grid or user requirements, the gas can be upgraded to the preferred methane concentration.

Learn about our CO2 liquefaction / recovery technology to recover the CO2 of the biogas upgrading process producing liquefied bio-CO2.

The Bright Renewables process


The methane-rich product gas can be used for different purposes. One of the options is to use the gas as transport fuel (CNG) for cars.


Another option is to inject the obtained gas into the natural gas grid.


The COthat is removed from the biogas can be recovered and liquefied to create an extra source of revenue for the plant owner.

  • Pre-treatment of biogas

    Before the CO2 can be removed, it is necessary to dry the biogas and remove hydrogen sulphide (H2S) and other contaminants which can damage the membranes or that need to be removed to meet the specification of the gas grid or other specific application. Hydrogen sulphide and other contaminants are removed from the biogas using a double active carbon filter. Water is removed by cooling the biogas to approximately 5°C with a chiller.

  • Compression and heat recovery

    After the pre-treatment of the biogas, the biogas is compressed to the necessary pressure for upgrading by membranes. The heat of the drying of the biogas, the heat from the compressor and the heat from cooling the gas after the compressor may be recovered by using a patented heat recovery system, this option makes it possible to recover the optimal amount of heat, so less energy is needed.

  • Separation by 3 stage membrane arrangement

    For the separation of carbon dioxide Bright Renewables uses membranes with the highest selectivity available in the market. They pass CO2 easier and quicker than methane. The membrane modules in the system are arranged in 3 stages. In this patented design the permeate gas from the different stages is recirculated to obtain the highest efficiency (>99.5%) and lowest methane loss (<0.5%). This is a significantly lower methane slip value than many other biogas purification technologies.


Bright Renewables - Noyal-Chatillon, France | Biogas Upgrading System