Compression characteristics of excess activated sludges treated by freezing-and-thawing process.

• Kawasaki Kenji

  Department of Applied Chemistry, Ehime University

• Matsuda Akira

  Department of Applied Chemistry, Ehime University

• Mizukawa Yuichi

  Department of Applied Chemistry, Ehime University

抄録

Excess activated sludge is very difficult to be filtered, but its solid–liquid separation characteristics can be improved by a freezing-and-thawing process. In this study, centrifugal and the gravitational settling experiments were done by using unfrozen and frozen activated sludges.<BR>An equation for the average solid compressive pressure ((p_s)_av) in the sediment zone was derived, based on the general equation for the local compression characteristics of a solid–liquid mixture. Also, the relationship between (p_s)_av and the average porosity ((ε_s)_av) in the sediment zone (1 – (ε_s)_av) = E(p_s)_av^β; E and β = constants) was confirmed by centrifugal and the gravitational settling experiments.<BR>The order of magnitude of (ε)_av was unfrozen sample < fast-frozen sample < slow-frozen sample. This order was consistent with that of the average specific filtration resistance obtained from the constant-pressure filtration experiments reported in a previous paper.

収録刊行物

• JOURNAL OF CHEMICAL ENGINEERING OF JAPAN

  JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 24 (6), 743-748, 1991

  公益社団法人 化学工学会

キーワード

• Solid–Liquid Separation
• Sedimentation
• Centrifugal Settling
• Compression Characteristic
• Porosity
• Solid Compressive Pressure
• Freezing-Thawing
• Activated Sludge

詳細情報

• CRID: 1390282679543798016
• NII論文ID: 130000021694
• DOI: 10.1252/jcej.24.743
• COI: 1:CAS:528:DyaK38XptVKhtw%3D%3D
• ISSN: 18811299
• ISSN: 00219592
• ISSN: http://id.crossref.org/issn/00219592
• Web Site: http://www.jstage.jst.go.jp/article/jcej/24/6/24_6_743/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可