Liquid Fertilizer Production System by Complemental Integration between Methane Fermentation and Aerobic Treatment

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06336
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 41050:Environmental agriculture-related
• Research Institution: Saga University
• Principal Investigator: Tanaka Munehiro 佐賀大学, 農学部, 教授 (50295028)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: メタン発酵 / 好気処理 / 草本系バイオマス / 液肥 / 植害試験

Outline of Final Research Achievements

In order to clarify the conditions for coupling methane between methane fermentation and liquid aerobic thermophilic treatment, the liquid fertilizer conversion experiments were conducted using both methods coupled with barley stems and leaves of herbaceous biomass for the model materials as a carbon resource, then verified the amount of unit heating value and fertilizer characteristics of the treated liquid. Methane fermentation using barley as the C resource resulted in 66% contribution rate and a net methane production rate was 6.2 L/gC (0.28 mol/gC). In the aerobic treatment, the calorific values were increasing by barley additions, but the increase was only about 2°C above the ambient air temperature. Treated liquid by the aerobic treatment showed similar properties to fully ripe compost. By the plant growth inhibition tests, there were no inhibitions for plant growth and extremely good fertility of aerobically treated liquid.

Free Research Field

農業環境工学

Academic Significance and Societal Importance of the Research Achievements

メタン発酵技術は，食品残さ，屎尿，家畜糞尿，汚泥などの有機物を材料としたエネルギー生産と消化液の肥料供給を可能とする資源化処理技術として注目されている。しかし，地域によって発生する有機物資源の種類は様々であるため，メタン発酵のみでは多様なバイオマス資源へフレキシブルに対応した安定処理を行う事が困難であった。そこで，本研究ではメタン発酵と好気処理の融合処理技術を発案した。また，廃棄バイオマスの微生物処理で問題となる炭素源の不足に対して，未利用資源である草本系バイオマスが有効な炭素源となることを確認した。さらに最終生産物の液体肥料は完熟堆肥と同レベルの品質を示すことを明らかにした。