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International Training program for young researcher (ITP)
Microbial induced carbonate precipitation
for the remediation of soil and geo-environment
Akiko NAKANO, PhD (Institute of Tropical Agriculture, Kyushu University)
Supervised by Dr. Leon van Paassen
Technical University of Delft in the Netherlands
1. Asia preliminary survey
Water Resource University
(Hanoi, Vietnam)
24.AUG.2011~ 31.AUG.2011
• Water Resource University (Hanoi, Vietnam)
Thai Nguyen
Thai Nguyen Province (North of Hanoi) 100km north from Hanoi central city paddy field, corn and tea field
Thai Nguyen University of Agriculture and Forestry
Dr. Nguyen Thi Thu Hang
Lecturer, PhD
• Erosion and collapse of slope area
Polluted river in Hanoi central city
2. EU Training Microbiological calcium carbonate precipitation
for ground improvement, “BioGrout”
Technical University of Delft (Delft, the Netherlands)
01. SEP. 2011 ~ 17. FEB. 2012
Supervised by Dr. Leon van PAASSEN (Delft University of Technology) Dr. Wouter van der STAR (Deltares, the Netherlands)
Dr. Leon van Paassen Assistant Professor
Dr. Wouter van der Star Principal Investigator
Dr. Timo Heimovaara Professor
Technical University of Delft (the Netherlands) Deltares (Delft, the Netherlands) Sep. 2011~May . 2012 (8months)
Grouting is a process whereby fluid materials such as chemical grout or cement material are injected into the subsurface soil or rock by using high pressure hydraulic pump.
Grouting is effective primarily for the improvement of soil strength and prevention of excessive settlement by filling the voids with some type of grouting materials .
Advantage: 1. Applicable for the ground
where any structures and buildings already exist .
Disadvantage: 1. High Cost 2. Influence for the
surrounding environment
What is Grouting?
In recent years, the innovative technique has lead to several investigations. That is based on microbial induced carbonate
precipitation, known as “Bio-Grout” .
-New grouting technique- Microbial induced carbonate precipitation
“Bio-Grouting”
Natural phenomenon of Bio cementation
Coral
Calcium carbonate stone at seashore
Limestone cave
BioGrout process (BioGrouting / Biocementation)
• nontoxic microorganisms (bacteria) instead of cement and/or chemical grout as grouting material
• Inorganic carbonate minerals (e.g. CaCO3) induced by bacterial catalysis with addition of some substrates for the reaction (= BioGrout)
urease positive bacteria - Most common process in recent Bio Grout researches
nitrifying/denitrifying bacteria Yeast another reducing bacteria for specific elements (e.g. iron Fe and sulfate SO4
2-)
Basic idea of BioGrouting by Urease positive bacteria
Urease positive bacteria
Ca2+
Effect of Bio Grout
It is expected that this technique will be various potential application for natural soil environment, soil foundation and construction.
• Liquefaction prevention
• Building settlement reduction
• Scour/Erosion prevention
• Bluff and slope stabilization
• Impermeable and reactive barriers
• Groundwater protection
• Emergency immobilization
• Aquifer storage and recovery
• Etc….
Bioreactor: Incubation of urease positive bacteria (Sporosarcina Pasteurii (DSM 33))
Column test
Water Flow 1 pv
(= 4.5 L) Per
40-50 min
Blank After Bio Grouting
NOT cemented (low or no CaCO3)
Well cemented (high CaCO3
concentration)
Launched by Deltares
Potential Application for Piping Construction
3. Asia Training
Water Resource University (Hanoi, Vietnam)
10.AUG.2012 ~ 21.AUG.2012
Supervised by Dr. Pham Huu Sy
Required research field for BioGrout
• Vietnam Academy of Science and Technology
• Marine Bio Chemical Institute
• Water Resources University
• Hanoi University of Mining and Geology
• Geotechnical Institute
Microbiology
Biotechnology
Geo-technology
Geology
Bio-Geo-technology