Biocorrosion, Biodeterioration, and Biofouling in Civil Engineering
Prevention of biodeterioration, biocorrosion, and biofouling of the construction materials is a task of Construction Biotechnology. Almost all construction materials can deteriorate due to microbial oxidation/reduction of C-, Fe-, S-, and N-containing com
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Biocorrosion, Biodeterioration, and Biofouling in Civil Engineering
13.1
Microbial Biodeterioration of Construction Materials
Almost all construction materials can deteriorate due to microbial oxidation/ reduction, hydrolysis, production of acids, alkali, and oxygen radicals. Timber in buildings and other wooden structures decay due to growth on their surface fungi and bacteria that hydrolyze cellulose, hemicelluloses, and degrade lignin. Dry rot, brown rot, and white rot of the timber are due to the different species of fungi specializing on biodegradation of cellulose or lignin. Mineral acids or alkali excreted by the microorganisms cause a microbial deterioration of construction materials. For example, corrosion of steel and cement, and deterioration of marble constructions can be caused by the formation of sulfuric acid S þ 1:5O2 þ H2 O ! 2H þ þ SO2 4 Performed, for example by Acidithiobacillus, or nitric acids
sulfur-oxidizing
bacteria
NH4þ þ 1:5O2 ! 2H þ þ NO 2 þ H2 O
ð13:1Þ from
the
genus ð13:2Þ
Performed, for example by ammonium-oxidizing bacteria from the genus Nitrosomonas.
© Springer Science+Business Media Singapore 2017 V. Ivanov and V. Stabnikov, Construction Biotechnology, Green Energy and Technology, DOI 10.1007/978-981-10-1445-1_13
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13.2
Biocorrosion, Biodeterioration, and Biofouling …
Deterioration of Cultural Heritage
Wood and paper can be easily biodegraded by the microorganisms under humid conditions. Objects of art, sculptures, and historical buildings are also deteriorated by microorganisms in humid and polluted atmosphere. For example, the marble statue shown in Fig. 13.1 has black plums due to the formation of black CaS, which can be described by the following reactions: SO2 ðreleased to air by the vehiclesÞ þ H2 O þ 0:5O2 ! H2 SO4
ð13:3Þ
H2 SO4 þ 2CH2 O ! H2 S þ 2CO2 þ 2H2 O ðbacterial sulfate reductionÞ
ð13:4Þ
CaCO3 ðwhite marbleÞ þ H2 S ! CaS ðblack matterÞ þ H2 O þ CO2
ð13:5Þ
Another example is biodeterioration of the column in the ancient Roman Temple of Minerva in Assisi caused probably by ammonifying and nitrifying bacteria (Fig. 13.2), in the upper layer of soil where the bottom part of the columns was embedded at some period of time: COðNH2 Þ2 þ 3H2 O ! 2NH4þ þ CO2 þ 2OH
ð13:6Þ
RðCOOÞNH2 þ chemical energy þ ½2H ¼ bioreductant ! RCOOH þ NH3 ð13:7Þ
13.3
þ NH4þ þ 2O2 ! NO 3 þ 2H þ H2 O
ð13:8Þ
CaCO3 þ 2H þ ! Ca2 þ þ CO2 " þ H2 O
ð13:9Þ
Microbial Biofouling
Microbial biofouling is the undesirable accumulation of microorganisms or products of their biogeochemical activity on submerged structures or facilities contacting with water such as groundwater wells, the pipes, coastal structures, equipment of municipal and industrial water systems, heat exchanger surfaces, air conditioners. Fouling could be due accumulation of microbial biomass, slime of microbial exopolysaccharide, scale of amorphous or crystal precipitate of calcium carbonate, ferric hydroxide, struvite Mg(NH4)PO4 induced by increase of pH and carbonate concentration by microorgan
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