Mitigation of scaling problem in drainage pipes for landfill basin

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06562
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Reaction engineering/Process system
• Research Institution: Fukushima National College of Technology
• Principal Investigator: Kurumada Kenichi 福島工業高等専門学校, 化学・バイオ工学科, 教授 (80273473)
• Research Collaborator: YAMAGUCHI Hiroyuki ひめゆり総業株式会社 ; HONGÕ Kazuhiro ひめゆり総業株式会社 ; MIDORIKAWA Takehiko 独立行政法人国立高等専門学校機構, 福島工業高等専門学校, 教授 ; ÕKUBO Hiromi 独立行政法人国立高等専門学校機構, 福島工業高等専門学校, 研究補助員
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 埋立処分場降雨浸出水 / 排水管系統内壁 / 不溶塩由来硬質スケール形成 / 樹脂表面上核発生サイト / 彎曲鱗片析出 / 鱗片相互結着起因管内完全閉塞 / 恒常的微生物代謝活動起因不溶性炭酸塩晶析 / 配管系統流入前集中型不溶塩晶析除去方法

Outline of Final Research Achievements

Landfill sites suffer cloggings in the drainage pipes with hard scales which grow rapidly after beginning the operation. The outside appearance of the scale sampled at the actual landfill site reflects the formation scheme of the hard solid scales where they are constituted from millimeter-thick flakes firmly agglomerated with each other. It also suggests that those hard flakes nucleate on the surface of the inner surface of the drainage pipe whose predominant constituent is PVC. As indicated by related previous works, the scale is almost purely from calcite. The scanning electron microscope observation revealed the hard scale to form via microbially induced calcite precipitation. The inner wall of the drainage pipe provides nucleation sites due to the preferable surface properties for the bacteria to dwell on after being transferred there by the water flow from the landfilled soil. The alternative nucleation sites should be provided for retarding the in-pipe growth of the scale.

Free Research Field

化学工学，環境工学，流体工学，応用生物化学工学，界面応用工学，晶析，核発生，水質管理