pH variation in sewers has a significant effect on hydrogen sulfide production and emissions, and hence its accurate prediction is critical for the optimization of mitigation strategies. In this study, the nature and dynamics of pH variation in a sewer system is examined. Three sewer systems collecting domestic wastewater were monitored, with pH in all cases showing large diurnal variations. pH...

Nitrogen is a main contaminant of wastewater worldwide. Novel processes for nitrogen removal have been developed over the last several decades. One of these is the partial nitritation process. This process includes the oxidation of ammonium to nitrite without the generation of nitrate. The partial nitritation process has several advantages over traditional nitrification-denitrification processe...

Many countries strive to reduce the emissions of nitrogen compounds (ammonia, nitrate, NOx) to the surface waters and the atmosphere. Since mainstream domestic wastewater treatment systems are usually already overloaded with ammonia, a dedicated nitrogen removal from concentrated secondary or industrial wastewaters is often more cost-effective than the disposal of such wastes to domestic wastew...

The paper will report about the experiences at an Austrian large wastewater treatment plant of 720,000 population equivalents, where anaerobically digested sewage sludge is further stabilised under aerobic conditions. Enhanced stabilisation of the anaerobically digested sludge was required at the plant in order to get a permit for landfill disposal of the dewatered stabilized sludge. By impleme...

_Treating the wastewater with high level of urea and ammonia-nitrogen is one of the problems faced by urea fertilizer plants in Indonesia. The alternative treatment being studied is the one which uses Fenton oxidation process which is continued with the use of Pseudomonas fluorescens bacteria. This study is conducted with the concentration of ammonia-nitrogen of 2500 ppm, 2000 ppm, and 1500 ppm...

ANaerobic AMMonium OXidation (Anammox) is an efficient microbiological process for the removal of ammonia nitrogen from wastewater. Although several Anammox reactors have been operated successfully in European water pollution control plants, there are challenges associated with the process which must be addressed to ensure dependable performance when treating high strength wastestreams in New Y...

Immobilized cells entrapped within a polymer matrix or attached onto the surface of a solid support have advantages over their free-cell counterpart, with easier harvesting of the biomass, enhanced wastewater treatment, and enriched bioproduct generation. Immobilized microalgae have been used for a diverse number of bioprocesses including gaining access to high-value products (biohydrogen, biod...

The effects of ammonium (NH4) and magnesium (Mg) on the precipitation of phosphorus in artificial wastewater by an air-cathode single-chamber microbial fuel cell were investigated. When both NH4 and Mg were added to the wastewater, phosphorus was precipitated as struvite. Almost no precipitation occurred with the addition of only NH4, while phosphorus was precipitated as cattiite with the addit...

A laboratory continuous feed biofilm reactor, comprising a bulk fluid reactor, a biofilm plastic module, a feed tank, and pneumatic devices and controls, was operated for a total period of 257 days, including seeding time, to treat domestic-strength synthetic wastewater under increasing ammonium nitrogen (NH(4)(+)--N) loading rates, ranging from 0.17+/-0.01 (0.71+/-0.06 gm(-2)d(-1)) to 0.70+/-0...

A novel wastewater treatment technology, suitable for centralised and decentralised wastewater treatment and known as a pumped flow biofilm reactor (PFBR), has been developed and patented in the National University of Ireland, Galway (NUI Galway). This two-reactor-tank technology has been extensively tested at laboratory-scale and trialled at a number of sites for populations ranging from 15 – ...