Sulphate-reducing Bacteria SRB

Critchley and Javaherdashti [74], Beech et al. [6] and, more completely, Jones and Amy [75] give a detailed list of the bacteria that could be involved in corrosion where SRB are just one of these bacterial groups. 

In this section, two examples of the wide spectrum of the bacteria involved in biocorrosion are described the well-known sulphate-reducing bacteria (SRB) and the relatively unknown iron-reducing bacteria (IRB). 

Sulphate-reducing bacteria (SRB) daive their energy from organic nutrients. They are anaerobic in other words, they do not require oxygen for growth and activity. 

SO as an alternative to oxygen, these bacteria use sulphate with the consequent production of sulphide [11]. 

It has also been reported that 50% of healthy individuals have significant populations of SRB in faeces compared to the 96% of Ulcerative colitis (an acute and chronic inflammatory disease of the large bowel) sufferers especially Ha/t Desulfovibrio genus, see [87]  

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General corrosion damage was the cause of failure of an A1 alloy welded pipe assembly in an aircraft bowser which was attacked by a deicing-fluid — water mixture at small weld defects . Selective attack has been reported in welded cupro-nickel subjected to estuarine and seawater environments . It was the consequence of the combination of alloy element segregation in the weld metal and the action of sulphate reducing bacteria (SRB). Sulphide-coated Cu-enriched areas were cathodic relative to the adjacent Ni-rich areas where, in the latter, the sulphides were being continuously removed by the turbulence. Sulphite ions seemed to act as a mild inhibitor. 

The most widely accepted criterion for protection of steel at room temperature (the protection potential) in aerobic conditions is - 0 - 85 V with respect to a Cu/CuSOa reference electrode. In anaerobic conditions -0-95 V (vs. Cu/CuSOa) is the preferred protection potential because of the possible presence of active sulphate-reducing bacteria (SRB). 

Togo CA, Mutambanengwe CCZ, Whiteley CG (2008) Decolourization and degradation of textile dyes using a sulphate reducing bacteria (SRB) - biodigester microflora co-culture. Afr J Biotechnol 7(2) 114-121... 

This ionic mercury (Hgll) adheres to aerosols and thus has a short (days to weeks) residence time in the atmosphere rainfall delivers it to the local soils and rivers. Ionic mercury is readily methylated (eqn. 5.24) by both abiotic and biotic pathways. However, most scientists now agree that methylation by anaerobic sulphate reducing bacteria (SRB) is most important. 

Keywords Sulphate-reducing bacteria (SRB) General anaerobic bacteria (GAnB) Petroleum Surfactants Most probable number (MPN)... 

If there is no access to air, there is usually no significant corrosion on ferrous materials when pH > 5. However, in some environments, heavy localized corrosion may occur due to bacteria that thrive in near neutral environment (pH = 5-8) at temperatures of 10-40°C in the absence of air (anaerobic bacteria). These bacteria promote reduction of present sulphate to sulphide. Hence, they are usually called sulphate-reducing bacteria (SRB). The classical mechanism comprises the following reactions at/on the cathodes [6.16] ... 

To exclude the H2S in the produced biogas, prevent the corrosion caused by sulphate reducing bacteria (SRB), and increase methane production, Ahanunad et al. [78] found support materials made of nylon that could selectively immobilize metha-nogens and completely eliminate SRB. Figure 25 shows the SEM photographs of the... 

SRB Tubes contain a medium developed at Nalco for the selection of anaerobic bacteria called Sulphate-Reducing Bacteria (SRB). This medium was designed to provide an anaerobic environment, eliminating the need for specialised incubation equipment. The tubes must be melted and then cooled (48°C/118°F) prior to use. 

Due to the natural occurrence of the sulphate reducing bacteria (SRB), sulphate reduction can... 

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