Dynamics of biofilm formation

Abstract

[Excerpt] Biofilms found in industrial systems are composed by living organisms such as bacteria, fungi and algae, and by non-living material such as inorganic particles and extracellular substances produced by the microorganisms. Biofilms are unwanted in heat exchangers, tubes, valves, etc. , Cthe so-called biofouling). Oppositelly, their biological activity finds a very useful application in water and wastewater treatment. The growth of microbial films on surfaces in contact with a circulating fluid involves different steps : the formation of a "conditioning film" made of organic molecules existing in the fluid ; the attachment of microorganisms to the surface, ei~her by direct contact or with the assistance of biopolymers excreted by the cells ; the growth and reproduction of the microorganisms, together with the production of a biopolymer network, at the expenses of the nutrients available in the fluid ; the sloughing off (erosion, removal> of parts of the biofilm by the action of the flowing fluid. [...]