Numerous facilities, mainly wastewater treatment plants, concentrate high levels of H2S and VOCs in their atmospheric emissions. These compounds are mainly responsible for the impact of bad odors that these facilities cause. For this reason, these compounds must be eliminated to reduce the environmental impact.
Advanced Biotrickling is a biopercolation system where the air to be treated circulates in an upward direction and passes through various stages in which there is a pH gradient. Thanks to an adequate contact time between water and air, it is possible to purify mainly H2S and, to a lesser extent, other odoriferous compounds too such as some volatile organic compounds.
It should be noted that this system, unlike other conventional biotricklings, does not require a water recirculation pump, assuming high savings derived from the cost of maintenance and electrical consumption. This fact also allows a pH gradient to exist in the wash column. In the lower part it is more acidic, due to the presence of antioxidant microorganisms that transform H2S into sulfuric acid that acidifies the medium. In this area, only these microorganisms live comfortably and consequently at this stage only the H2S is purified. However, in the upper part of the column, once the H2S has been reduced, the pH is neutral and other types of microorganisms can then live and can purify other odoriferous compounds.