5. Pure oxygen treatment of industrial effluents

An overview of gas applications in the food industry would not be complete without mentioning the treatment of the effluents they produce. Indeed, 40% of industrial effluents come from the food industry. Fortunately, these effluents are easily biodegradable. For several years now, industrial sites have been equipped with "activated sludge" or "lagooning" wastewater treatment plants. These conventional treatment processes have proved capable of achieving a large proportion of the targets set. However, increased production, stricter discharge standards (nitrogen pollution treatment, etc.) and greater sensitivity to the need for proper operation mean that we now have to resort to complementary techniques, in particular the introduction of pure oxygen into a biological tank, using two approaches:

• doping, providing pure oxygen in addition to the...