Asahi Breweries use biogas from its own wastewater treatment process to power factory

Asahi Group Holdings, Ltd. announced that it can purify the biomethane gas (biogas) produced in the wastewater treatment process at breweries into high-purity biogas suitable for Solid Oxide Fuel Cell (SOFC) power generation. The purified biogas can be used as fuel.

The move came after Asahi conducted a power generation experiment on a SOFC power generation test device which is jointly developed with Kyushu University Next-Generation Fuel Cell Research Centre, and they were able to successfully generate electricity for more than 2000 consecutive hours.

So far, Asahi has introduced wastewater treatment equipment using anaerobic technologies at its 13 breweries in Japan, where wastewater discharged from the manufacturing process by a fermentation method were treated and biogas is produced. This plant-derived, carbon-neutral biogas is then burned in boilers, among other uses, and reused as heat energy in the facilities. If the biogas was to be used in SOFC power generation to produce electricity more efficiently, CO2 emissions are expected to be further reduced.

When biogas is used in SOFC power generation, impurities in the gas can interfere with power generation. For steady power generation, it is important to rid the impurities. To resolve this, Asahi has created a new purification process and developed a system that can produce high-purity biogas at a low start-up cost.

Since Asahi started continuous power generation on a test SOFC power generation device, the device has been operating smoothly for more than 2000 consecutive hours without any occurrence of the biogas inhibiting power generation. The company says it will continue the test for up to 10,000 hours to investigate seasonal variations from using biogas.