Development of grass utilization technology as a feedstock for small-scale methane fermentation system suitable for rural area

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K18349
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Rural environmental engineering/Planning; Environmental agriculture(including landscape science)
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: Nakamura Masato 国立研究開発法人農業・食品産業技術総合研究機構, 農村工学研究部門, 上級研究員 (60414463)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: メタン発酵 / 消化液 / コバルト / 資源循環 / C/N比 / ADF

Outline of Final Research Achievements

Methane fermentation experiments were conducted to develop co-digestion system of sludge from small-scale wastewater treatment plants in rural areas (WWTPRs) and grass. The results indicated that gas production rates were different among variety of grasses and generally large in grasses harvested in spring and summer compared with that in fall. Moreover, there was a tendency for the gas production rate to be large when C/N ratio and ADF of grassed is low. In addition, the results also revealed that the addition of Co is required for stable digestion of sludge from WWTPRs because the Co concentration of sludge from WWTPRs in Japan is generally low.

Free Research Field

地域環境工学

Academic Significance and Societal Importance of the Research Achievements

農業集落排水施設では維持管理費の削減が課題であるが、その大部分を汚泥処理費（63%）、電気料（18%）が占めることから、汚泥の利活用とエネルギー生産を同時に実現できるメタン発酵システムの導入は有望な解決策である。本研究で開発を行った、農村地域で発生する刈草と農業集落排水汚泥を原料とする小規模メタン発酵システムをさらに発展させ、現地に適用することにより、農業集落排水施設の維持管理費削減とともに、農村地域の低投入でコンパクトな資源循環システムが実現できる。