Agitating liquids in an unbaffled surface aeration tank leads to the formation of a vortex in the region of the impeller shaft. The types and characteristics of the vortex govern the process phenomena of a surface aeration tank. In the present work, experimental results and empirical correlations have been obtained to relate the vortex depth to a number of physical factors. Experiments have bee...

The effect of different aeration rates on the organic matter (OM) degradation during the active phase of oil palm empty fruit bunch (EFB)-rabbit manure co-composting process under constant forced-aeration system has been studied. Four different aeration rates, 0.13 L min(-1) kg(DM)(-1),0.26 L min(-1) kg(DM)(-1),0.49 L min(-1) kg(DM)(-1) and 0.74 L min(-1) kg(DM)(-1) were applied. 0.26 L min(-1)...

The flow characteristics of raw sewage directly affect the technical and economic performance of sewage-source heat pump systems. The purpose of this research is to characterize the flow characteristics of sewage by experimental means. A sophisticated and flexible experimental apparatus was designed and constructed. Then the flow characteristics of the raw sewage were studied through laboratori...

Sludge generated in waste water treatment process can be a major sink for some pharmaceutical and personal care products (PPCPs). The land application of sewage sludge (in the form of biosolids in the United States) can therefore potentially introduce PPCPs into the environment. After treatment, biosolids are often subjected to a storage period before land application. However, little informati...

Activated sludge was successfully incorporated as the biocatalyst in the fast, ferricyanide-mediated biochemical oxygen demand (FM-BOD) bioassay. Sludge preparation procedures were optimized for three potential biocatalysts; aeration basin mixed liquor, aerobic digester sludge and return activated sludge. Following a 24h starving period, the return activated sludge and mixed liquor sludges repo...

Viab le pathogens are generally present at every stage of wastewater treatment. Thus a potential airborne infectious pathway due to microbial aerosols exists~ particularly at activated sludge treatment plants. In this study the concentration of sewage-borne indicator bacteria and viruses in effZuent aerosols was determined and the exposure to such aerosols by treatment plant workers was estimat...

In this study, New Delhi metallo-beta-lactamase (NDM)-producing Enterobacteriaceae were identified in Irish recreational waters and sewage. Indistinguishable NDM-producing Escherichia coli by pulsed-field gel electrophoresis were isolated from sewage, a fresh water stream and a human source. NDM-producing Klebsiella pneumoniae isolated from sewage and seawater in the same area were closely rela...

In this study two wet microalgae cultures and one dried microalgae culture were co-digested in different proportions with sewage sludge in mesophilic and thermophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of sewage sludge alone. The results showed that co-digestion with both wet and dried microal...

The game model of sewage charges, based on incremental mode, was developed. Four modes of high/low sewage charge standards were utilized to analyze the relationship between control strategy on sewage discharge and the development of environmental protection industry. Results showed that the selection of control strategy was heavily dependent on the level of sewage charges. An empirical study wa...