Biological Odour control System

The OCU is a biological reactor based on biotrickling filtration for the treatment of air emissions polluted with hydrogen sulfide (H2S) and other primary sources of wastewater odors such as organic compounds (VOCs) and mercaptans. The operational principle of the OCU is based on biological reactions performed by heterotrophic and autotrophic microorganisms immobilized on the surface of an inert packing material (creating a biofilm) that remove and oxidize the pollutants of the air emissions to harmless products to be emitted to the atmosphere.

This process involves different stages: first the pollutants are transferred from the gas phase to the liquid phase, then there is diffusion of the pollutants through the liquid phase and through the biofilm phase, finally it is in the biofilm where the biodegradation takes place by the microorganisms.

WEIE guarantees an H2S outlet concentration of 0.5 ppm or 99% removal efficiency, and an outlet odour concentration of 1500 OU/m3 or 95% odour removal. This high and robust performance is achieved by the high level of engineering of the system, which consists ofwinded plastic packing media (OdourPack) of specific surface area greater than 400 m2/m3 and a porosity greater than 92%. All the surface of the packing material is available for the biomass growth, so there are no internal pore structures that can get inaccessible to the oxygen and the pollutants once biomass grows, which would reduce the real residence time of the bioreactor. Contrary to random packing materials, the characteristics of the packing promotes biofilm detachment to keep a thin biofilm that enhances mass transfer of oxygen and pollutant, keeping a high real residence time.

The OdourPack is chemically resistant with a life time guarantee greater than 10 years, and its structure allows placing the winded layers from 1 up to 9 meters of height without compaction problems and without plastic debris that can clog water pipes. If necessary, the OdourPack can be easily removed and installed again in the bioreactor vessel without interfering, if this action is done, with the original configuration.

If final effluent from WWTP/STP is not available, a nutrient dosing system connected to the water spray system, and also controlled via the PLC is installed to provide the necessary nutrients for the biological process.

The Sulphus has a low energy consumption because of the low pressure drop of the system due to the high porosity of the OdourPack and the low spraying regime (normally around 10% of the time), and very low maintenance requirements.