Concentrating waste fluid from methane fermentation to utilize as fertilizers.

2014 Fiscal Year Final Research Report

• Project/Area Number: 26660049
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant nutrition/Soil science
• Research Institution: Kyoto University
• Principal Investigator: MATOH TORU 京都大学, (連合)農学研究科(研究院), 教授 (50157393)
• Co-Investigator(Kenkyū-buntansha): OCHIAI Kumiko 京都大学, 大学院農学研究科, 助教 (40533302)
• Project Period (FY): 2014-04-01 – 2015-03-31
• Keywords: メタン発酵 / 肥料 / 硫酸アンモニウム / リン酸肥料

Outline of Final Research Achievements

Waste fluid of methane fermentation was fractionated based on its fertilizer components. First, the fluid was passed through a sieve having 20 mesh, to separate undigested rice straw. The straw was finely chopped and partially fermented, therefore, its physical properties are suitable for preparation of seeding bed. The fluid was then babbled with hot air. The hot air take ammonia completely out from the fluid reducing the volume to 90% of the origin. The ammonia gas was then passed through sulfuric acid and ammonia was converted to ammonium sulfate. Thus, ammonia could be converted to ammonium sulfate. Continuous babbling with hot air reduced the volume and resulted in dark-colored sticky precipitate like pitch. The pitch like precipitate contains all phosphorus and potassium which the waste fluid contained. A plant cultivation test with this pitch-like substance revealed that the phosphorus and potassium were fully active as phosphate and potassium fertilizers.

Free Research Field

植物栄養学