1. Basic principles

The principle of aerobic biodegradation is based on the degradation by microorganisms (bacteria, fungi, etc.) of organic compounds, in this case called the substrate. These oxidation reactions must take place in an aqueous medium in which the microbial consortia are present. These may be free-living or immobilized on a solid support. In environmental protection bioprocesses, and in particular in biological water purification, aerobic or anoxic activated sludge basins are used, which can be assimilated to fully mixed reactors, or bacterial beds, which are columns in which the water to be treated circulates over a colonized packing ...