• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Effects of raw water and coagulant characteristics on the composition and physico-chemical properties of meso-particles remaining after coagulation

Research Project

Project/Area Number 19K15127
Research Category

Grant-in-Aid for Early-Career Scientists

Allocation TypeMulti-year Fund
Review Section Basic Section 22060:Environmental systems for civil engineering-related
Research InstitutionChuo University

Principal Investigator

DING QING  中央大学, 研究開発機構, 機構助教 (70837476)

Project Period (FY) 2019-04-01 – 2023-03-31
Project Status Completed (Fiscal Year 2022)
Budget Amount *help
¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000)
Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Fiscal Year 2019: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Keywordsメソ粒子 / 膜目詰まり / ゼータ電位 / バイオポリマー / 凝集剤 / 膜ファウリング
Outline of Research at the Start

浄水処理で多用される凝集技術では、凝集後に残存する微小な粒子(20~500 nm;メソ粒子と定義)の制御が課題となっている。メソ粒子が荷電中和される条件には最も後段の膜ろ過への影響が軽減されることが解っている。しかし、国内で市販されている凝集剤PAClは、メソ粒子を酸性pH側で荷電中和できるが、中性pHにおいてはどれだけ凝集剤を注入しても荷電中和できないことが明らかになっている。このことから、メソ粒子の荷電中和には既存の凝集理論で説明できないメカニズムがあると考える。そこで本研究では、メソ粒子の構成成分と物理化学的特性、および凝集剤特性がメソ粒子の物理化学的特性に与える影響について検討する。

Outline of Final Research Achievements

In drinking water treatment, it is important to control the meso-particles (20-500 nm) remaining after coagulation, since neutralization of meso-particles could improve the performance of the subsequent membrane filtration or sand filtration after coagulation. However, polyaluminum chloride, a commercially available coagulant in Japan, cannot neutralize meso-particles at the neutral pH normally used in water purification plants.
In this study, the results showed that the composition of meso-particles differed depending on the amount of coagulant addition. The reason why meso-particles cannot be charge-neutralized at neutral pH was found to be that meso-particles derived from raw water or coagulant are both negatively charged. In the future, it will be necessary to develop a coagulant that is positively charged at neutral pH, which can neutralize the meso-particle charge.

Academic Significance and Societal Importance of the Research Achievements

本研究では、メソ粒子の構成成分・物理化学特性を検討し、それらの凝集機構は既存の凝集機構とは異なることを示した。この結果は、既存の凝集理論を拡張し、メソからミリまでのすべての粒子を包含するような、新しい凝集理論の確立に有意義なものである。また、本研究の成果は、浄水処理における凝集-砂ろ過/膜ろ過プロセスの制御に参考になる。

Report

(5 results)
  • 2022 Annual Research Report   Final Research Report ( PDF )
  • 2021 Research-status Report
  • 2020 Research-status Report
  • 2019 Research-status Report
  • Research Products

    (7 results)

All 2022 2021 2020 2019

All Presentation (6 results) (of which Int'l Joint Research: 3 results,  Invited: 2 results) Funded Workshop (1 results)

  • [Presentation] Applying pre-ozonation to reduce the low molecular weight fraction that plays a cross-linking role between meso fraction and membrane surface2022

    • Author(s)
      Qing Ding, Danru Zhao, Naoki Murata, Nobuhiro Aoki, Hiroshi Yamamura
    • Organizer
      The 13th International Symposium on Southeast Asian Water Environment
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 凝集ー砂ろ過における残留微粒子数と残留Alの低減2022

    • Author(s)
      丁青
    • Organizer
      第56回日本水環境学会年会
    • Related Report
      2021 Research-status Report
  • [Presentation] フロック特性による凝集ー膜ろ過の制御2021

    • Author(s)
      丁青
    • Organizer
      第37回ニューメンブレンテクノロジーシンポジウム
    • Related Report
      2021 Research-status Report
    • Invited
  • [Presentation] 凝集-膜ろ過における可逆的ファウリングに寄与するフロック特性の解明2020

    • Author(s)
      丁 青、濱田 祐綺、山村 寛、渡辺 義公
    • Organizer
      第54回日本水環境学会年会
    • Related Report
      2020 Research-status Report
  • [Presentation] Coagulation characteristics of colloids indicating irreversible membrane fouling in coagulation-MF membrane filtration process2020

    • Author(s)
      Qing Ding
    • Organizer
      The International Membrane Science & Technology Conference
    • Related Report
      2019 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Composition of meso-particles in pre-coagulation using PACl2019

    • Author(s)
      Qing Ding, Hiroshi Yamamura, Keisuke Takiguchi, Taro Oe, Yoshimasa Watanabe
    • Organizer
      The 9th International Water Association (IWA) Membrane Technology Conference & Exhibition for Water and Wastewater Treatment and Reuse
    • Related Report
      2019 Research-status Report
    • Int'l Joint Research
  • [Funded Workshop] The International Membrane Science & Technology Conference2020

    • Related Report
      2019 Research-status Report

URL: 

Published: 2019-04-18   Modified: 2024-01-30  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi