Biocement is produced through a process called microbial induced carbonate precipitation, which uses microorganisms to precipitate calcium carbonate. Bacillus pasteurii bacteria are mixed with a urea/calcium solution which is then injected into sand, where the bacteria metabolize urea and induce calcium carbonate mineralization over 24 hours. Biocement requires less energy and emissions to produce than ordinary cement and increases compressive strength while helping to remediate cracks in buildings and regain strength within 28 days. However, further studies are needed to optimize ingredients and assess long-term efficacy and feasibility compared to chemical methods.

1. Done by
Pratika Rane
Msc. Biotechnology
Part I
Goa university
1

2.  Construction material consumes a large amount of
nonrenewable resources.
 5% of carbon dioxide emission is caused due to
production cement.
 For producing 1 tone of cement it requires 1M ETU of
energy.
 The buildings and traditional structures get
deteriorated after a given time.
2

3. It refers to CaCo3 deposit that is formed due to the
microorganisms activity in the system which is rich in calcium
ions.
3

4.  Bacillus pasteurii with urea hydrolysis mechanism.
The cementation process occurs in pipe columns filled
with commercial sand contained silica.
 Urea/calcium solution and bacteria solution were
mixed immediately and put in the pressurized vessel
to be injected to the sand core in pipe column for
several time until the sand core fully saturated. Bio
cementation takes about 24 hours to complete the
reaction, after that the bio cement were dried in
temperature of 60˚C.
4

5.  It needs a much shorter time for production and the in-situ
process raw material of bio cement are produced at low
temperature.
 It consume less energy and less CO2 emission in the
production process as compared to other ordinary cement.
 It increases compressive strength of mortar by up to 38%.
 Bio cement can remediate cracks in building materials and
monumental stones and regain strength within 28 days.
5

6. Bio cementation is a process to produce binding material (bio
cement) based on microbial induced carbonate precipitation
(MICP) mechanism.
6

7. First ever complete bio-cement
building
7

8. The above is a picture of a construction made of bio concrete. It
may be observed that the cracks are self-healed
8

9.  The cracks are formed on the surface of concrete due to many reasons
like shrinkage, Inadequate water for hydration …etc,
 The water is deliberately forced into the crack and the precursor is
activated
 Ca(C3H5O2)2 + 7O2 → CaCO3 + 5CO2 + 5H2O
 CO2 + Ca(OH)2 → CaCO3 + H2O
 The activated precursor inturn induces the bacteria to react with
that precursor and form a base of calcium carbonate called as
limestone, the chemical equation is given above.
9

10. This bio concrete absorbs and reduces atmospheric co2.
It supports biological growth on its on surface.
This are called vertical gardens.
The material lends itself to a new concept of vertical garden, not only for
newly built constructions, but also for the renovation of existing
buildings. Unlike the current vegetated façade and vertical garden
systems, the new material supports biological growth on its own surface;
therefore, complex supporting structures are not required, and it is
possible to choose the area of the façade to which the biological growth is
to be applied. 10

11.  This method is more complex than the chemical one
as the microbial activity depends on many
environmental factors including temperature, pH,
concentrations and diffusion rates of nutrients and
metabolites etc.
 Successful commercialization of the technique
requires economical alternatives of the medium
ingredients that cost as high as 60% of the total
operating costs.
11

12.  Comparative studies should be done to check the
feasibility of this method with that of the chemical
methods which should include environmental impacts
as well as cost.
 Long term efficacy of these bio minerals should be
investigated
12

13.  Achal V, Mukherjee A, Reddy MS (2010) Microbial concrete: way to enhance the
durability of building structures.JMater,23:730 734.doi: 10.1061/ (ASCE)
MT.1943-5533.0000159
 Achal V, Mukherjee A, Reddy MS (2011) Effect of calcifying bacteria on
permeation properties of concrete structures. J Ind Microbiol Biotechnol
38:1229 1234. doi:10.1007/s10295-010-0901-8
 Arunaye FI, Mwasha A (2011) On behavior of limited life geotextile materials for
reinforcing embankment on soft ground. World J Eng 8:195 199.
doi:10.1260/1708-5284.8.2.195
 Bang SS, Galinat JK, Ramakrishnan V (2001) Calcite precipitation induced by
polyurethaneimmobilized Bacillus pasteurii. Enzyme Microb Technol 28:404
409
 Bang S, Min SH, Bang SS (2011) Application of microbiologically induced soil
stabilization technique for dust suppression. Int J Geo-Eng 3:27 37
 Barlaz MA, Staley BF, De Los Reyes III FL (2010) Anaerobic biodegradation of
solid waste. In: Mitchell R, Gu JD (eds) Environmental microbiology, 2nd edn.
Wiley, Hoboken, NJ, USA,pp 281 299
13