Plenary 11: In-Sewer Processes 2 - H2S
3:30pm - 3:50pm
H2S control through an original channel
UNIV LYON, INSA LYON, DEEP, 69621 Villeurbanne, France
Hydrogen sulphide (H2S) is one of the most common gases encountered in gravity sewers. It causes odour nuisance and is also dangerous for humans. It can have serious consequences on the health of sewage workers. In this paper a nature-based solution favouring the release of H2S and its filtration in an original channel is proposed and is evaluated through CFD modelling approach.The proposed channel operates in a proper way. The hydraulic jump increases the turbulent kinetic energy leading to the massive release of H2S. Then natural ventilation directs the air to the filter.
3:50pm - 4:10pm
Liquid H2S Online Measurement for Optimized Sewer System Insights and H2S Control
1Hach, France; 2Hach, USA
In order to prevent corrosion in the collection system and prevent public complaints caused by nuisance odours, water utilities use chemicals to mitigate hydrogen sulfide (H2S). By dynamically adjusting the chemical dosing rate to match real-time liquid-phase H2S concentrations from an online sensor, the effectiveness of ferrous sulfate (FeSO4) dosing at the end-of-pipe improved while chemical consumption dropped by 50%.
4:10pm - 4:30pm
Continuous measurement of dissolved sulphide in sewers
1EnviDan A/S; 2Aarhus Water A/S; 3Aalborg University, Denmark
The city of Aarhus, Denmark, with its 400,000 PE and its 1,632 km of sewers, experiences odour and corrosion problems. These have intensified over the last decades as wastewater treatment has been centralized, combined systems converted to separate ones, and water consumption has declined. In this presentation, a catchment-wide measuring campaign of pH and dissolved H2S gas (using SulfiLoggerTM) is presented, and benefits and issues related to the approach discussed. Finally, the applicability for calibrating a sewer process model, Mega-WATS, is touched on.