Making sake requires a lot of water. In addition to brewing water, the water used for washing and other miscellaneous purposes is 30 to 50 times the amount of water used for the raw rice. Much of the water used is then discharged as wastewater. In particular, the wastewater from washing rice has a large environmental impact and must be discharged after appropriate wastewater treatment. Since 2016, our company has been using micro-organisms to methane ferment the wastewater and other substances generated in the sake production process. This methane fermentation reduces the eutrophic components in the wastewater and produces biogas that can be used more effectively. The biogas extracted from the methane fermentation is then returned to the company as fuel for the boilers used to produce steam and hot water for the steaming of rice and other processes at the factory.

(Photo left) Biogas holder (Photo right) Methane fermenter