Abstract
The mechanical properties of soil (cohesion, friction, stiffness and permeability) are important parameters for engineering constructions and ecosystems in sedimentary environments. BioGrout is an in situ soil strengthening technique involving microbial-induced carbonate precipitation (MICP). This process involves hydrolysis of urea by bacteria containing the enzyme urease in the presence of dissolved calcium ions, resulting in calcium carbonate precipitation. In order to control the BioGrout process for engineering applications, it is necessary to improve understanding of the relevant phenomena and develop efficiencies to enable up-scaling of the technology to suit commercial applications. Control of a homogeneous distribution of bacterial activity in a sand bed is considered crucial in order to prevent clogging during injection and provide homogeneous reinforcement results. This paper describes a methodology to distribute and fix bacteria (with their enzyme activity) relatively homogeneously in a sand bed, before supplying cementation reagents. The methodology is based on a two-phase injection procedure: a bacterial suspension is injected into the sand body, immediately followed by a fixation fluid (i.e. a solution with high salt content). It is proposed that bacteria are retarded by adsorption and filtration processes and are permanently adsorbed to the sand grains when overtaken by the fixation fluid. The presented experimental approach for optimizing bacterial fixation in porous media can be used as a tool to design the treatment protocol for engineering applications in practice.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 112-117 |
| Number of pages | 6 |
| Journal | Ecological Engineering |
| Volume | 36 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 1 2010 |
| Externally published | Yes |
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Keywords
- Bacterial fixation
- BioGrout
- Calcium carbonate
- Enzyme activity
- Microbial-induced carbonate precipitation (MICP)
- SmartSoils
- Soil reinforcement
- Urease
ASJC Scopus subject areas
- Environmental Engineering
- Nature and Landscape Conservation
- Management, Monitoring, Policy and Law
Cite this
Fixation and distribution of bacterial activity in sand to induce carbonate precipitation for ground reinforcement. / Harkes, Marien P.; van Paassen, Leon; Booster, Jacco L.; Whiffin, Victoria S.; van Loosdrecht, Mark C.M.
In: Ecological Engineering, Vol. 36, No. 2, 01.02.2010, p. 112-117.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Fixation and distribution of bacterial activity in sand to induce carbonate precipitation for ground reinforcement
AU - Harkes, Marien P.
AU - van Paassen, Leon
AU - Booster, Jacco L.
AU - Whiffin, Victoria S.
AU - van Loosdrecht, Mark C.M.
PY - 2010/2/1
Y1 - 2010/2/1
N2 - The mechanical properties of soil (cohesion, friction, stiffness and permeability) are important parameters for engineering constructions and ecosystems in sedimentary environments. BioGrout is an in situ soil strengthening technique involving microbial-induced carbonate precipitation (MICP). This process involves hydrolysis of urea by bacteria containing the enzyme urease in the presence of dissolved calcium ions, resulting in calcium carbonate precipitation. In order to control the BioGrout process for engineering applications, it is necessary to improve understanding of the relevant phenomena and develop efficiencies to enable up-scaling of the technology to suit commercial applications. Control of a homogeneous distribution of bacterial activity in a sand bed is considered crucial in order to prevent clogging during injection and provide homogeneous reinforcement results. This paper describes a methodology to distribute and fix bacteria (with their enzyme activity) relatively homogeneously in a sand bed, before supplying cementation reagents. The methodology is based on a two-phase injection procedure: a bacterial suspension is injected into the sand body, immediately followed by a fixation fluid (i.e. a solution with high salt content). It is proposed that bacteria are retarded by adsorption and filtration processes and are permanently adsorbed to the sand grains when overtaken by the fixation fluid. The presented experimental approach for optimizing bacterial fixation in porous media can be used as a tool to design the treatment protocol for engineering applications in practice.
AB - The mechanical properties of soil (cohesion, friction, stiffness and permeability) are important parameters for engineering constructions and ecosystems in sedimentary environments. BioGrout is an in situ soil strengthening technique involving microbial-induced carbonate precipitation (MICP). This process involves hydrolysis of urea by bacteria containing the enzyme urease in the presence of dissolved calcium ions, resulting in calcium carbonate precipitation. In order to control the BioGrout process for engineering applications, it is necessary to improve understanding of the relevant phenomena and develop efficiencies to enable up-scaling of the technology to suit commercial applications. Control of a homogeneous distribution of bacterial activity in a sand bed is considered crucial in order to prevent clogging during injection and provide homogeneous reinforcement results. This paper describes a methodology to distribute and fix bacteria (with their enzyme activity) relatively homogeneously in a sand bed, before supplying cementation reagents. The methodology is based on a two-phase injection procedure: a bacterial suspension is injected into the sand body, immediately followed by a fixation fluid (i.e. a solution with high salt content). It is proposed that bacteria are retarded by adsorption and filtration processes and are permanently adsorbed to the sand grains when overtaken by the fixation fluid. The presented experimental approach for optimizing bacterial fixation in porous media can be used as a tool to design the treatment protocol for engineering applications in practice.
KW - Bacterial fixation
KW - BioGrout
KW - Calcium carbonate
KW - Enzyme activity
KW - Microbial-induced carbonate precipitation (MICP)
KW - SmartSoils
KW - Soil reinforcement
KW - Urease
UR - http://www.scopus.com/inward/record.url?scp=74149086499&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=74149086499&partnerID=8YFLogxK
U2 - 10.1016/j.ecoleng.2009.01.004
DO - 10.1016/j.ecoleng.2009.01.004
M3 - Article
VL - 36
SP - 112
EP - 117
JO - Ecological Engineering
JF - Ecological Engineering
SN - 0925-8574
IS - 2
ER -