Study On Ship Sliming May Enable Reduced Costs And Emissions
Slime build-up on cargo ships significantly impacts fuel efficiency, leading to increased emissions and higher consumer prices. Researchers at KTH Royal Institute of Technology have developed a groundbreaking model to estimate biofilm growth on ship hulls. This model aims to help ship operators schedule hull cleaning more effectively, ultimately saving on fuel consumption.
Understanding Biofilm Growth and Its Impact
Biofilm fouling begins when micro-colonies of bacteria attach to a ship’s hull. These bacteria form base structures that develop into string-shaped streamers. Together, these elements create surface imperfections that increase friction between the hull and water. According to Cornelius Wittig, a PhD student in fluid mechanics at KTH, the rate of this fouling process varies based on the shear stress induced by fluid flow against the surface.
The consequences of slime fouling are significant. Wittig notes that a ship covered with a thin biofilm can experience up to an 80% increase in fuel consumption. This increase in fluid friction can require a vessel’s shaft power to rise by as much as 18%. Unfortunately, many ship operators only schedule cleaning after noticing a spike in fuel consumption, often too late to prevent excessive fuel waste. Timing is crucial for effective de-fouling, and the new model aims to provide operators with the necessary insights to optimize their cleaning schedules.
Wittig emphasizes that the potential fuel savings from timely cleaning must outweigh the costs of dry-docking and cleaning procedures. Accurate predictions of biofilm growth will enable ship operators to make informed decisions about when to clean their vessels. While the model shows promise, further research is needed to validate its effectiveness under realistic conditions. The findings were published in the journal NPJ Biofilms and Microbiomes, highlighting the broader implications of biofilm management in various fields, including medicine and dentistry.
