Calcium-enriched Biochar: Pyrolysis of Digested Sludge, Phosphorus Recovery, and Fertilizer Properties

Naokatsu KANNARI, Takumi UESUGI, Keiichi KUBOTA, Daichi MASUDA, Kazuyoshi SATO, Takayuki TAKARADA, Tomohide WATANABE
2020 Nihon Enerugi Gakkaishi/Journal of the Japan Institute of Energy  
In this study, we prepared calcium (Ca)-enriched biochar from digested sludge derived from food waste at pyrolysis temperatures in the range of 600 to 900 °C. We evaluated the properties of phosphorus (P) recovery of the biochar and the fertilizer properties of the biochar after the P recovery (P-loaded biochar). The results showed that the amount of P recovery increased with increasing pyrolysis temperature, while the P recovery capacity of biochar was consistently high at all the investigated
more » ... temperatures. The fertilizer properties of P-loaded Caenriched biochar prepared at 600 °C, evaluated by the komatsuna cultivation test were comparable to the chemical fertilizer Ca(H2PO4)2. The results suggest that the Ca-enriched biochar could serve as a P recovery material and an environmentally friendly fertilizer. 本研究では,食品廃棄物由来の消化汚泥を異なる温度で熱分解することでカルシウム (Ca)リッチバイオチャーを調製し,そ のリン回収特性および肥料特性を評価した。バイオチャーのリン (P)回収量は熱分解温度の上昇とともに増加した。P 回収後の 600℃処理バイオチャーの肥料特性を小松菜栽培試験により評価した。その結果,P 回収後のバイオチャーは,化学肥料である Ca(H2PO4)2 と同等以上の肥料効果を示すことがわかった。これらの結果よ り,Ca リッチバイオチャーは,P 回収に対して有用であり, 環境負荷の小さい肥料として利用できることを明らかにした。
doi:10.3775/jie.99.236 fatcat:ygbwknvitfakhgjn2hj65ggaua