| Autor: |
Satoshi ASAOKA, Tetsuji Okuda, Hitomi YANO, Kouji YOSHITSUGU, Satoshi NAKAI, Wataru NISHIJIMA, Kenji SUGIMOTO, Daijirou Matsunami, Yorihide ASAOKA, Mitsumasa OKADA |
| Zdroj: |
Proceedings of the International Conference on Waste Technology & Management; 2012, p1314-1323, 10p |
| Abstrakt: |
Seagrass beds and tidal flats are facing in danger of disappearing. Steel slags from steel industries are one of the promising materials to restore seagrass beds and tidal flats. The dissolution of calcium called 'free lime' released from the slags was considered to be main reaction of the slags though its aging processes. However, the aging behaviors in seawater are not fully understood. This study aimed to reveal the aging processes of slags on the basis of chemical reactions controlling reactive depth, and also determine the maximum dissolving potential of calcium and reactive depth of these slags in order to understand their maximum reaction potential in the sea. Decarburized or dephosphorized slags were submerged to seawater or sediments for 36 weeks. After the regular intervals, chemical composition, surface chemical properties and in-depth profile of elements were measured using XRF and EPMA. Under the seawater condition, the reactive depth where calcium was dissolved increased through its aging processes, while that of the slags in sediments was almost negligible. It is considered that the pozzolanic reaction and formation of magnesium hydroxide on the surface of the slags prevented their aging processes. The maximum amount of calcium dissolved from the slags in the sea could be calculated by the maximum calcium dissolving potential and the reactive depth in the sea. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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