Odor reduction during livestock waste composting by adding biochar

2024 Fiscal Year Final Research Report

• Project/Area Number: 20K06313
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 41040:Agricultural environmental engineering and agricultural information engineering-related
• Research Institution: Iwate University
• Principal Investigator: Maeda Takeki 岩手大学, 農学部, 教授 (40333760)
• Project Period (FY): 2020-04-01 – 2025-03-31
• Keywords: 悪臭 / バイオ炭 / 家畜排せつ物 / 堆肥化 / バイオマス

Outline of Final Research Achievements

Adsorption tests using a mixture of lower fatty acids simulating dairy manure showed that biochar could remove large amounts of n-butyric acid and iso-valeric acid. A mixture was prepared by mixing dairy manure with compost and then adding three types of commercially available biochar equivalent to 2% of the wet mass of the mixture. A composting experiment was conducted for one week. Regarding VFAs in the material, n-butyric acid and iso-valeric acid were significantly lower in only one type of biochar compared to the control before composting. The odor index equivalent values were significantly lower in the two types of biochar compared to the control both before and after composting. Biochar may contribute to reducing the odor of livestock manure, although its effect is limited.

Free Research Field

農業環境工学

Academic Significance and Societal Importance of the Research Achievements

バイオ炭の土壌への施用は土壌機能を改善するとされ，多くの研究がなされてきた。本研究のように，家畜排せつ物堆肥化時に発生する悪臭の低減のためにバイオ炭を副資材の一部として用いる研究は国外では数多く行われているものの，国内での研究例は非常に少ない。
国内では住宅地の拡大や住民意識の変化などにより，畜産施設の悪臭対策への要望が強く，堆肥化施設に併設される脱臭装置の開発・改良が行われてきた。しかし，牛ふんなどでは脱臭装置を設置しないことも多く，材料への添加材により堆肥化時の悪臭を抑制することが望まれる。こうした簡易な方法による対応は，堆肥化施設の悪臭対策への貢献は大きく，本研究の意義は大きい。