Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11-10 (pristine concrete) to pH 2-4. Acidophilic microorganisms become established as biofilms within the...

Biochemical reactions that occur in sewer pipes produce a considerable amount of hydrogen sulfide gas (H2S corrosive and poisonous), methane gas (CH4 explosive and a major climate change contributor), carbon dioxide (CO2 a major climate change contributor), and other volatile substances (collectively known as in-sewer gases). These toxic gases lead to contamination of natural environment, sewer...

Activated sludge treatment allows only for a partial removal of micropollutants, mainly via sorption and biological degradation. Ozonation and activated carbon filtration are processes bearing the potential to drastically reduce the micropollutant load discharged to the environment after (centralized) biological treatment. The estimated total costs between 0.05 and 0.20 euro per m3 treated wate...

This research undertaken at the University of Sheffield aims to provide a better understanding of the interaction above/below ground urban floods. A newly constructed unique experimental facility has been developed in the water lab, and it includes a sewer system, composed by 3 main pipes, 6 manholes and a CSO (Combined Sewer Overflow), and a preliminary urban surface with the slope 1/1000. Thi...

Model Predictive Control (MPC) of combined sewer systems can reduce environmental degradation caused by uncontrolled overflows. However, practical uncertainties are often neglected when assessing the potential MPC strategies. This paper aims to understand risks associated with using a non-perfect internal MPC-model, real precipitation forecast, and realistic dynamic system capacity fluctuations...