【地域資源開発学科】バイオマス焼却灰からのK-ストラバイトとしての回収とアルミニウムの分離

Endar Hidayat, Hadi Imran A. Halem, Yoshiharu Mitoma, Hiroyuki Harada

Phosphorus (P) and potassium (K) are non-renewable materials and widely in many industries such as agricultural sectors. On the other hand, the demand of P and K as fertilizers increases which following global population. The nutrient source of P and K which get from biomass waste i.e. incinerated of activated sludge and coffee husk biochar, respectively. The present study was conducted recovery of P and K as struvite-K (KMgPO4·6H2O) precipitates. The results showed that aluminium was released simultaneously with P from incinerated activated sludge with precipitate of Al:P of 1:1, K:P of 0.5, and Mg:P of 3. However, aluminium was inhibited to form struvite-K. Then, we examined cation removal especially for removed Al by dissolved 0.5 M HNO3 and the solution was mixed with KH2PO4 and MgCl2·6H2O as source of K and Mg, respectively. The results showed aluminium (Al) was removed with precipitate K:P of 0.5, and Mg:P of 0.8. This study was confirmed that recovery of biomass incinerated was successful as struvite-K and can be used as fertilizers.

　リン（P）とカリウム（K）は再生不可能な材料であり、農業部門などの多くの産業で広く使用されています。一方、肥料としてのPとKの需要は、世界の人口に続いて増加しています。バイオマス廃棄物からPとKの栄養源を回収することを目的としました。それは、ストルバイト-K（KMgPO4∙6H2O）として回収します。　その結果、アルミニウムは、Al：Pが1：1、K：Pが0.5、Mg：Pが3の沈殿物を含む汚泥炭からそれぞれの成分がPと同時に溶出しましたが、アルミニウムの溶出は0.5 M HNO3によって抑制されて純度の高いストルバイト-Kを形成した。