Reducing biofouling in ships' cooling systems Cleaning up the effects of biofouling represents a major expense for the shipping industry, costing tens of billions of euros each year worldwide. Until now, no effective technology existed to control the growth and settlement of marine organisms on cooling systems. Industrial Technologies © Thinkstock Biofouling is caused by the larvae of marine organisms attaching themselves to surfaces in contact with seawater and rapidly growing to adult size. Its removal involves the use of expensive techniques such as high-pressure hoses. Biofouling preventive methods such as chlorination of pipe work or anti-fouling coatings are unfortunately accompanied by significant environmental impact. Efficient operation of a vessel's seawater-based cooling system is compromised when they are obstructed by colonising marine invertebrates and seaweed. The blockage of inlet pipes for cooling water and/or a drop in heat exchange efficiency can cause an increase in the working temperature of engines and other appliances. The result is a possible shorter working life and risk to the vessel's safety. The EU-funded BIOFOULCONTROL project addressed the problem of biofouling by developing innovative technology that disperses ozone into the cooling water. This has the effect of deactivating the marine organisms that may settle in the cooling system. The ozonation system also minimises the generation of products that are toxic to the marine environment. An intelligent control unit was built to monitor the process and manage ozone dosage to ensure the system's optimum operation. The integrated BIOFOULSYSTEM was then installed and tested onboard an offshore supply vessel. The technology can also be applied to other sectors working in the marine environment, such as aquaculture, ocean thermal power generators, offshore platforms and water supply systems. The BIOFOULCONTROL project successfully developed a cost-effective, eco-friendly, user-friendly and reliable ozone feeding and dispersion unit to control marine biofouling on heat exchangers of vessels.
