凍結解凍前処理による泥の脱水性の改善:氷結晶の形態学制御 凝固とリオロジック強化
Yajun Wu1, Ruilong Li1, Xudong Zhang1
1Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China.
Environmental research
|September 5, 2025
まとめ
凍結解凍コンディショニングは,泥の脱水を改善します. 低温,特に -28°Cと -36°Cは,泥の凝固を促進し,フラック構造を破壊することによって,水分を60%以下に減らす.
科学分野:
- 環境工学
- 材料科学
- 水処理技術
背景:
- 都市部の泥は,水分と粘度が高いため,脱水と流動性の問題を抱えています.
- 凍結解凍 (F/T) コンディショニングは,粘液管理のための有望で環境に優しい前処理です.
- 冷却温度がF/T効率に与える影響を理解することは,泥の脱水を最適化するために極めて重要です.
研究 の 目的:
- 冷却温度が泥の脱水性やリオロジカルな性質に及ぼす影響を調査する.
- 泥の凍結解凍状態を制御する微細構造的メカニズムを解明する.
- 最適なF/Tパラメータを決定し,泥の凝固を向上させ,水分を減少させる.
主な方法:
- 試料は冷却温度で凍結解凍サイクルを繰り返した.
- 氷の結晶の形成とフラックの構造の変化の顕微鏡観察
- 泥の圧縮と流動性を評価するレオロギー分析
- 凝固と浸透性の測定を含む脱水性試験
主要な成果:
- 最適な凝固と透かし性は - 28°Cで観察されました.
- - 36°Cで圧縮と流動性の改善が認められた.
- - 28°Cと - 36°Cの両方で圧縮フィルタリングの後,水分は60%未満に減少しました.
- 氷の結晶の成長は 氷の構造を壊し ネットワークを弱め 排水を改善しました
結論:
- F/Tコンディショニング中の低冷却温度により,スランプの脱水効率が向上します.
- 氷の結晶の形成とその後のフラックの破壊は,脱水性の改善のための重要なメカニズムです.
- F/T処理後の構造的緩和と粒子集積の改善が確認されています.
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