Investigating on biofouling in cooling water systems: mechanisms, problems, and remedies

Most industries including power plants, refineries, and utility units mainly use water as their coolant. Water generally flows through heat exchangers in order to transfer excess heat in the process and back to its reservoir. Due to water shortage, it is critical to minimize water usage in the most efficient manner.Fouling is defined as the buildup of unwanted substances on the surface and therefore biofouling is microbial depositing on the surface. This well-known phenomenon increases heat transfer resistance, pressure drop, and causes localized corrosion of the surface, thus, it’s highly recommended to prevent the formation of microbial films by adding biocides to kill microorganisms and perform routine cleanings to enhance the heat transfer efficiency.Above mentioned complications leads to an increment in energy consumption that is highly notable while working with a fossil fuel-fired power stations as it leads to a greater use of fuel and higher CO2 production. In this review, freshwater cooling systems, fouling and biofouling formation mechanisms, problems, prevention and cleaning methods have been discussed in more depth.