Microbial Corrosion in Cooling Tower of Ramin Power Plant: Determination and Corrective Solution

Document Type : Case study


1 Assist. Prof., Dept. of Chemical and Process Engineering, Niroo, Research Institute Tehran, Iran

2 Chemistry Manager, Dept. of Chemistry Engineering, Ramin Thermal Power Plant, Ahwaz, Iran


There is a great importance in investigating and measuring microbial corrosion in the cooling tower of thermal power plants, especially in the case of open cycles. Moreover, this issue becomes more important in the situation where the source of water supply for cooling tower is river or sea water. In this research, the cooling tower water for Ramin Power Plant, which is supplied from the Karun River, is examined as a point of of microbial growth. For this purpose, microbial tests including TBC (general test) and specific bacteria tests such as APB, FP, IRB, NRB, Aero, SRB and TRB, physicochemical tests (conductivity, salinity, pH, turbidity) and the amount anions and cations, are carried out in the water sample of the cooling tower. In the TBC test, the approximate number of bacterial colonies is 107 cfu/ml, which is in a very heavy range. The results of APB and IRB test indicate the value is much higher than the permissible limit and the presence of Aero bacteria. On the other hand, in the analysis of anion and cation, sulfate and chlorine species have a very high concentration of more than 1000 ppm. Therefore, to deal with microbial factors, and as a solution in the first priority, the method of chlorination with water shock is recommended. The second priority includes the general method based on oxidizers such as ozonation and bromination. Selective removal of sulfate and nitrate ions is suggested as the third priority solution due to the high concentration of these ions and the intense activities of SRB and NRB bacteria.


Afshar, M. G., Azimi, M., Habibi, N., Masihi, H. & Esameilpour, M. 2023. Batch and continuous bleaching regimen in the cooling tower of Montazer Ghaem Power Plant. Journal of Hazardous Materials Advances, 11, 100339. https://doi.org/10.1016/j.hazadv.2023.100339.
Allan, M. 1999. Evaluation of Coatings and Mortars for Protection of Concrete Cooling Tower Structures from Microbiologically Influenced Corrosion in Geothermal Power Plants. Brookhaven National Lab.(BNL), Upton, NY (United States).
Behzadi, B., Noei, M., Azimi, A., Mirzaei, M. & Anaraki Ardakani, H. 2021. Experimental optimization of the disinfection performance of sodium hypochlorite and hypochlorous acid in pilot and industrial cooling towers. Iranian Journal of Oil and Gas Science and Technology, 10, 1-11. https://doi.org/10.22050/ijogst.2021.265594.1578.
Di Gregorio, L., Tandoi, V., Congestri, R., Rossetti, S. & Di Pippo, F. 2017. Unravelling the core microbiome of biofilms in cooling tower systems. Biofouling, 33, 793-806.
Fiehn, A. J. 1969. Cooling tower applications in power cycle design. Journal of the Power Division, 95, 55-62. https://doi.org/10.1080/08927014.2017.1367386.
Ghahraman Afshar, M., Esmaeilpour, M. & Ghaseminejad, H. 2023. Investigation of water consumption in Shahid Montazer Ghaem steam Power Plant and technical-economic evaluation of the boilers' blowdown recycling solutions. Nashrieh Shimi va Mohandesi Shimi Iran. (In Persian) (In Press)
Ilhan-Sungur, E. & Çotuk, A. 2010. Microbial corrosion of galvanized steel in a simulated recirculating cooling tower system. Corrosion Science, 52, 161-171. https://doi.org/10.1016/j.corsci.2009.08.049.
Licina, G. 1988. A Review of Microbial Induced Corrosion in Nuclear Power Plant Systems. National Assoc. of Corrosion Engineers Pub., Houston, USA.
Momeni, I., Danehkar, A., Karimi, S. & Khorasani, N. A. 2011. Dispersion modelling of SO2 pollution emitted from Ramin Ahwaz Power Plant using AERMOD model. Human and Environment, 9, 3-8. (In Persian)
Pope, D. 1987. Microbial corrosion in fossil-fired power plants: a study of microbiologically influenced corrosion and a practical guide for its treatment and prevention. Workshop Proceedings, Rensselaer Polytechnic Inst., Dept. of Biology. Troy, NY (USA).
Regucki, P., Engler, B. & Szeliga, Z. 2016. Analysis of water management at a closed cooling system of a power plant. Journal of Physics: Conference Series, IOP Publishing, 012026. https://doi.org/10.1088/1742-6596/760/1/012026.