Reborn of steelmaking slag as multi-functional fertilizer by the control of mineralogical structure.

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K14189
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Metal making/Resorce production engineering
• Research Institution: Tohoku University
• Principal Investigator: KITAMURA SHINYA 東北大学, 多元物質科学研究所, 教授 (80400422)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 製鋼スラグ / 肥料 / 溶出 / 鉄イオン / ガラス

Outline of Final Research Achievements

The supplement of Fe iron is imperative to suppress the “Aki-ochi” which means the sudden deteriorate of paddy growth in the early autumn. Steelmaking slag contains much Fe oxide and Fe ion mostly supplied from the glassy phase. In this research, dissolution behavior of Fe ion from glassy phase which synthesized by quenching of slags with various composition was investigated and clarified the condition to improve the dissolution efficiency. The basic condition of experiment was set as pH=5 and oxidation condition which simulated the early period after irrigation of paddy field and pH, oxidation-reduction potential (ORP) and acid to control pH were changed. The results showed that to improve the efficiency of Fe supply, the basicity (CaO/SiO2) should be controlled between 0.67 to 0.84, Fe oxide content should be larger than 30 mass% and the valence of Fe should be 2+ in CaO-FeOx-SiO2 glassy phase. In addition, the lower pH and lower ORP promoted the dissolution of Fe.

Free Research Field

金属資源生産工学