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In the concrete structures of petrochemical cooling towers, due to the effects of the chemical atmosphere and water vapor, the surface of these towers suffers severe weathering; cracks appear on the concrete surface, and in some areas of the tower columns, the reinforcing bars become visible. Some surfaces are covered with microorganisms. It affects the service life of the equipment. The reasons for the corrosion of cooling towers are as follows: (1) The acidic substances in industrial air react with tricalcium aluminate and calcium hydroxide hydrates present in the solidified product resulting from cement hydration, forming salts that are somewhat soluble. As these corrosive substances continue to be supplied and water is lost through evaporation, it leads to the degradation of the structural components. (2) When it rains, CO2 in the air reacts with water to form H2CO3, which gets trapped in the pores of the concrete. However, H2CO3 in water can also react further with CaCO3 to produce Ca(HCO3)2, which is soluble in water; this leads to the gradual dissolution and removal of the useful components within the concrete. The Ca(HCO3)2 that is removed is replaced by solid Ca2CO3, thereby damaging the concrete. (3) The circulating water has a calcium carbonate composition; when the cooling tower is in operation, some water vapor is carried away by the fans and sprayed onto the outer wall at the top of the tower. When CaCO3 in water is at saturation, there is a capacity to continue dissolving CaCO3 as well as the carbonates in concrete, resulting in a decrease in concrete strength. (4) Algae are floating on the inner surface of the cooling tower and the lower surface of the cooling tower columns. Due to bacteria produced in algal cells; for example, anaerobic sulfate-reducing bacteria often parasitize aerobic sulfur bacteria. Their reproduction leads to the corrosive damage of concrete structures.