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Effect of thermophilic sulphate-reducing bacteria (Desulfotomaculum geothermicum) isolated from Indian petroleum refinery on the corrosion of mild steel

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The role of thermophilic sulphate-reducing bacteria (SRB) Desulfotomaculum geothermicum in mild steel corrosion was evaluated by electrochemical study and surface analysis technique. In the presence of D. geo- thermicum, the corrosion rate was 0.0698 mmpy at 50°C, which was higher when compared to control. Polarization study revealed that the bacteria enhanced cathodic reaction and suppressed anodic reaction. XRD data revealed that the presence of FeS enhanced the cathodic reaction by the formation of a protective film on the metal surface. Pitting was observed by confocal microscopy, which may be due to cathodic depolarization. The study implicates the importance of D. geothermicum in the corrosion of cooling towers of the petroleum refinery. damage caused or accelerated by the presence of bacteria and other microorganisms and their metabolic activities on metals and alloys. Many types of bacteria, including sulphate-, iron- and CO2-reducing bacteria, sulphur-, iron- and manganese-oxidizing bacteria are associated with the MIC of metals and alloys 1 . Among them, sul- phate-reducing bacteria (SRB) are recognized as a major group involved in anaerobic corrosion. These latter mi- croorganisms can coexist in naturally occurring biofilms with a wide bacterial community, including fermentative bacteria, often forming synergistic communities (consortia) that are able to influence electrochemical processes through cooperative metabolism 2 . The sulphate reductive activity of SRB is thought to account for >75% of the corrosion in productive oil wells, and for >50% of the failures of buried pipelines and cables 3 . SRB are strictly anaerobic microorganisms responsible for the terminal mineralization of organic matter in anoxic environments. They are a diverse group of prokaryotes that may be divided into four groups based on rRNA sequence analysis: Gram-negative mesophilic SRB, Gram-positive spore-forming SRB, thermophilic bacterial SRB and thermophilic archael SRB 4
... The involvement of SRB in corrosion in different environments has been reported and reviewed by many researchers for more than five decades (Lee, Lewandowski, Nielsen, & Hamilton, 1995; Malard, Kervadec, Gil, Lefevre, & Malard, 2008; Halim, Watkin, & Gubner, 2012; Li, Whitfield, Krystyn, & Van Vliet, 2013). However, SRB corrosion at high temperatures is reported only by few workers (Villanueva, Martinez, Dlaz, Martinez, & Sanchez, 2006; Anandkumar, Choi, Venkatachari, & Maruthamuthu, 2009a; Anandkumar, Rajasekar, Choi, & Maruthamuthu, 2009b ). Microbiologically influenced corrosion (MIC), as an interdisciplinary subject and mechanism, can only be elucidated through chemistry, microbiology, and molecular biology. ...
... The cathodic depolarization theory proposed by von Wolzogen Kühr and van der Vlugt (1934) as given in Equations (1) to (7) was evidenced in both mesophilic and thermophilic SRB-influenced corrosion by many investigators (Villanueva et al., 2006; Anandkumar et al., 2009a; Anandkumar et al., 2009b). The thermophilic strain survive a temperature range of 50°C–80°C by forming spores, and their vegetative forms might develop and multiply when the optimum temperature for growth is encountered. ...
... The thermophilic strain survive a temperature range of 50°C–80°C by forming spores, and their vegetative forms might develop and multiply when the optimum temperature for growth is encountered. The organic film adsorbed on the metal surface reduces the anodic current where the biogenic product may improve the passivity of steel (Anandkumar et al., 2009a; Anandkumar et al., 2009b). Although passivity was noticed on the steel, it is assumed that the heterogeneity of bacterial attachment and temperature encourages the pitting corrosion on the metal surface. ...
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Sulfate-reducing bacteria (SRB), an anaerobic bacterial group, are found in many environments like freshwater, marine sediments, agricultural soil, and oil wells where sulfate is present. SRB derives energy from electron donors such as sulfate, elemental sulfur or metals, and fermenting nitrate. It is the major bacterial group involved in the microbiologically influenced corrosion (MIC), souring, and biofouling problems in oil-gas-producing facilities as well as transporting and storage facilities. SRB utilizes sulfate ions as an electron acceptor and produce H
... This data indicates that SRB did exist in the sediment around the piles and could be cultured to numbers significant enough to give rise to corrosion, as also found in Ref. [26], but could not be positively identified on the corrosion product taken from the pile surface, at least in the limited analysis performed. ...
... The FT-IR spectra from piles that show evidence of ALWC are compared with those where the corrosion appeared to be uniform in Fig. 14. The top two traces (piles with presumed ALWC) show peaks in similar positions to those reported from other FT-IR work on SRB corrosion of steel [26,27]. These include an intense peak at 1448 cm À1 reportedly showing the presence of carboxylate group, and several peaks in the ranges of 1660 cm À1 and 1200-900 cm À1 that indicate the presence of polysaccharides associated with the metabolism of SRB [26,27]. ...
... The top two traces (piles with presumed ALWC) show peaks in similar positions to those reported from other FT-IR work on SRB corrosion of steel [26,27]. These include an intense peak at 1448 cm À1 reportedly showing the presence of carboxylate group, and several peaks in the ranges of 1660 cm À1 and 1200-900 cm À1 that indicate the presence of polysaccharides associated with the metabolism of SRB [26,27]. ...
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This paper outlines the problem and analysis techniques in three exemplar case studies of marine concentrated corrosion. The intended audience is failure analysts or forensic engineers, who might occasionally come across examples of concentrated corrosion and are seeking relevant background information. In particular, it demonstrates the advantages in problem identification and solution that can accrue from the use of the highly sophisticated spectrographic instrumentation that is currently available. These techniques include energy dispersive spectroscopy (EDS) mapping in a scanning electron microscope (SEM), Fourier transform infrared (FT-IR) and Raman spectroscopy. Confocal laser scanning microscopy (CLSM) is also useful in surface metrology. The main case study presented is one of accelerated low water corrosion (ALWC) on the tubular steel piles of a marina. The paper includes an outline of some of the relevant literature relating to the use of these modern techniques in identifying marine corrosion products.
... On the one hand, they make related microorganisms react with the damaged metal. Like the corrosion of steel by giant bacillus [93], sulfurate-reducing bacteria (Desulfotomaculum geothermicum) have proved to be hugely disruptive in the refinery [94]. Corrosion by Bacillus subtilis and Bacillus circosus was observed in aircraft fuel tanks [95]. ...
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... Autochthonous microorganisms flourish in anoxic environments under high pressure, temperature, and salinity in crude oil and gas reservoirs. 1 Oil reservoir bacterial species are known as a global range of bacteria and archaea which have effectively acclimated to such physicochemical circumstances. 2 The antimicrobial activity in such habitats is essential for the oil industry because of the consequences that some of these organisms may have on extracting operations such as producing hydrogen sulfide (souring), metal corrosion, and pipeline plugging. 3,4 Aerobic and anaerobic bacterial growth has damaged the majority of the worldwide petroleum produced, 5 lowering its value and quality. The equilibrium between attraction and repulsion interactions of bacteria and solid interfaces has been termed bacterial adsorption. ...
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... SRB is an anaerobic (heterotrophic) acidogenic bacteria isolated from diverse environments. It is the predominant cause of corrosion and four times quicker than natural corrosion-promoting oxygen microbes (Anandkumar et al., 2009). SRB can dissolve the organic compounds and use sulfate ions as a terminal electron acceptor, to produce sulfides (hydrogen sulfide, bisulfide, sulfides) are direct attacks the metal surface and the final end product is corrosion that widely induces the pitting type of corrosion. ...
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In this review article, illustrating the impact and fundamental stuff of microbially influenced corrosion (MIC) along with mechanism, maintenance of materials, human life, wellbeing and inhibitors for cooling towers. Corrosion is a natural mechanism of oxidation and reduction of metal ions by chemical and electrochemical processes and microorganism accumulation. MIC occurs through the aggregation of microbes which can be secreting the extra polymeric substances (EPS) that oxidation of the metal sur- face. According to the reviews, in the cooling water system, the corrosion begins in the anode charge because its oxidation reaction quickly takes place on the metal surface than the cathode charge. Anni- hilate the corrosion process needs certain helper substances such as chemical or green compounds, called inhibitors. Corrosion inhibitors typically adopt the adsorption mechanism due to the presence of organic hetero atoms. Chemical and green inhibitors are used to prevent corrosion processes and since ancient times, vast quantities of chemical inhibitors have been used in industry due to their effectiveness and consistency. But still, the chemical inhibitors are more toxic to humans and the environment. Instead of chemical inhibitors, green inhibitors (natural products like plant leaves, flowers, stem, buds, roots and sea algae) are developed and used in industries. Generally, green inhibitors contain natural compounds, high inhibition efficiency, economic, eco- and human-friendly, and strong potential features against corrosion. Thus, a lot of research is ongoing to discover the green inhibitors in various parts of plants and seaweeds.
... SRB is an anaerobic (heterotrophic) acidogenic bacteria isolated from diverse environments. It is the predominant cause of corrosion and four times quicker than natural corrosion-promoting oxygen microbes (Anandkumar et al., 2009). SRB can dissolve the organic compounds and use sulfate ions as a terminal electron acceptor, to produce sulfides (hydrogen sulfide, bisulfide, sulfides) are direct attacks the metal surface and the final end product is corrosion that widely induces the pitting type of corrosion. ...
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Chapter
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The hydrogenotrophic sulfate-reducing bacterium (SRB) Desulfovibrio capillatus (DSM14982T) was isolated from an oil field separator with serious corrosion problems; this is the study of its role in the corrosion of carbon steels under anaerobic conditions. Immersion tests with two steel alloys, St-35.8 (typical carbon steel employed in European naval industry), and API-5XL52 (weathering alloy steel employed in Mexican oil industries) were performed. Total exposure was 45 days and different concentrations of thiosulfate as electron acceptor for bacterial growth were employed. The samples immersed in media with SRB undergo fast activation and numerous active sites form on the surface. Microscopic observations were made by environmental scanning electron microscopy (ESEM). Weight loss and electrochemical testing included open circuit potential (Ecorr), polarization resistance (Rp), electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) were measured with and without bacteria in the culture medium in order to determine corrosion rates and mechanisms. All electrochemical techniques have shown that after the end of the exponential phase the corrosion activity notably increased due to the high concentration of bacterial metabolites. Finally, the corrosion behavior of API-5XL52 was worse than St-35.8.
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