Growth of sulphate-reducing bacteria (SRB) depends on the metabolic activity of the microbe which is greatly influenced by environmental factors. The environmental factors such as pH and temperature may affect the microbial activity which contributes to the metal loss phenomenon due to corrosion process. The paper focuses on identifying the optimum value of pH and temperature that is most suitable for the constant growth of SRB which may lead to severe corrosion on carbon steel API 5L X70.

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... n steel coupons of size 20x10mm were exposed to the ATCC 7757 modified Baar's medium broth number 1249 at 37°C for the period of 30 days. Initially, a group of anaerobic vial samples were cultured in the medium with constant temperature and pH values ranging from 5.5 to 9.5. The carbon steel coupons were retrieved after 30 days of incubation to determine the amount of weight loss. Among the range of pH value, the optimum value of weight loss was recorded at pH 9.5. This optimum pH was then tested on the range of temperature varies between 5°C and 60°C. The calculation of weight loss and corrosion rate showed that the temperature of 37°C is the most favourable environment for the growth of bacteria with severe influence on the corrosion rate.