Microbial biofilm, the most important component of (micro) biofouling, represents a serious tech- nological issue, particularly where water is a critical process element. The biofilm can:
- Decrease thermal efficiency of heat exchangers (e.g. by 30% for a 20 microns-thick bacterial layer).
- Increase inorganic fouling, producing sticky substances which increase particles adhesion.
- Pave the way to bigger organisms settlement, the usually called macrofouling, which can constrict water flux, increasing energy consumption.
- Cause microbially-induced corrosion (MIC), which accounts for multi-billion dollars of industrial damages all over the world. These problems can eventually lead to pipe blockages and plant idle.
- Be dangerous for FOOD SAFETY.
Biofilm cleaning treatments must be applied as soon as bacteria start to settle on water-dipped surfaces, since:
- It is much more difficult and expensive, both in terms of detergents and disinfectant concentration and contact time, to deal with a mature biofilm, with respect to an early-stage one. As a matter of fact, since the first growth of biofilm extracellular matrix (EPS), biofilm resistance to external agents can increase by three order of magnitude (x1000).
- After reaching a pseudo-equilibrium condition, biofilm outmost layers tend to detach and float away. This increases the likelihood of biofilm formation in other plant sections.