A prominent but commonly overlooked issue that arises in Downstream oil & gas facilities is corrosion problems near and surrounding cooling towers. Cooling towers are used to expel waste heat from the process. Water is used as the medium to remove heat, based upon the principle of evaporative cooling. Because cooling towers are rarely taken out of operation, the atmosphere in and around the cooling tower is constantly warm and damp – providing the ideal conditions for corrosion. Exacerbating the problem is the fact that the environment includes scale deposits, contaminants from the process and microbiological growth, all of which accelerate the corrosion process.
In addition to the heightened risk of corrosion, the continuous generation of moisture creates a problem for carrying out coating maintenance, as most coatings require a clean and dry surface to cure properly. This unique challenge is often not well understood, leading to inadequate measures in maintenance – some as bizarre as waiting for the wind to change direction to reduce dampness, before sending in maintenance teams in to manually wipe down a surface and coat as quickly as possible. The result is that cooling towers and surrounding areas suffer from frequent coating failures and corrosion problems, leading to a belief that coatings in these areas are destined to fail in 1-2 years and routine maintenance should be designed to accommodate this.
As is often the case in such situations, there are coating technologies that can mitigate many of the corrosion problems faced in and around cooling towers. One such example is Interzone 954, a hydrocarbon modified, high build, heavy duty epoxy. Originally developed to protect structures in the harshest of operating conditions, such as splash zones on offshore structures, Interzone 954 is engineered to provide long term durability even in extremely corrosive environments. A hydrocarbon modification of the resin and a unique curing agent technology used in Interzone 954 enables application directly on damp surfaces and poorly prepared surfaces. It is even capable of being immersed in water as soon as an hour after application. This allows maintenance managers to schedule maintenance painting activities even when the surface is subject to continuous dampness. In addition, Interzone 954 is capable of application up to 500 microns (20 mils) in one coat, allowing it to act as a single coat maintenance product, enabling rapid turnaround of maintenance coating projects. This unique solution enables maintenance teams to break the cycle of reactive maintenance and take back control in mitigating the effects of corrosion in and around the cooling tower.