Production of Bacteria for Structural Concrete - Biotechnologies and Biomimetics for Civil Engineering - page 315

Table 14.1 Overview of BioCement applications with respect to target, microorganism used and
origin of country
Target Microorganism Origin References

Limestone protection Biocalcin

producing bacteria

France Adolphe et al. ( 1990 ),

Le Metayer-Levrel et al. ( 1999 )

Monumental stone
protection

Mytilus
californianus

Italy Tiano et al. ( 1992 ), Tiano ( 1995 )

Monumental stone
porosity

Micrococcus sp. Italy Tiano et al. ( 1999a )

Bacillus subtilis

Biochemical
properties of MICP

B. pasteurii USA Stocks-Fischer et al. ( 1999 )

Concrete crack
remediation

B. pasteurii USA Ramachandran et al. ( 2001 )

Ornamental stone
conservation

Myxococcus
xanthus

Spain Rodriguez-Navarro et al. ( 2003 )

Concrete durability B. sphaericus Belgium De Muynck et al. ( 2008 )

Concrete crack repair B. sphaericus Belgium Van Tittelboom et al. ( 2009 )

Compressive strength
of cement mortars

Shewanella sp. India Ghosh et al. ( 2005 )

Bacillus sp. CT-5 Achal et al. ( 2011b )

Greener media in
BioCement

S. pasteurii India Achal et al. ( 2009b , 2010a )

Corrosion prevention Bacillus sp. CT-5 India Achal et al. ( 2012b )

Bio-sandstone Alkalophilic

microbes, Bacillus
spp.

China Qian et al. ( 2010a ), Rong et al.

( 2012 ), Rong and Qian ( 2012 )

2-3 g/m 2 is applied in concrete, which costs about US $4 (3 €)/m 2 . The cost of
nutrients is estimated to be about US $250 (180 €)/kg. Based on this analysis, the
dosage for microbial concrete application will generally range between 0.04 and 0.
08 kg/m 2 , bringing the cost of nutrients to US $7-15 (5-10 €)/m 2

and the total

product cost is estimated around US $31-39 (23-28 €)/m 2 .
The additional cost during the preparation of biological mortar or microbial
concrete will be that of bacteria and nutrient; however, the cost of nutrients can be
reduced significantly by replacing standard or commercially available nutrients
with such industrial by products, rich in carbohydrate/protein/energy sources. Achal
et al. ( 2011c ) successfully reduced the cost of microbial concrete production by
replacing standard nutrient with corn steep liquor (CSL). Corn steep liquor can
typically be available locally with a price of nearly US $2 (1.5 €)/L, which is very
economic compared with standard nutrient medium and this brings the biodeposi-
tion cost to US $0.5-1.0 (0.3-0.7 €)/m 2 . The performance of CSL was significantly
better than standard laboratory nutrients in terms of microbial concrete production.
Hence, CSL offers an economic advantage over the standard nutrient medium and
the overall process cost reduces dramatically, and finding such other economic
nutrient solution is of need.