Search results for "sanita"

Variance-based sensitivity analysis for wastewater treatment plant modelling

2014

Global sensitivity analysis (GSA) is a valuable tool to support the use of mathematical models that characterise technical or natural systems. In the field of wastewater modelling, most of the recent applications of GSA use either regression-based methods, which require close to linear relationships between the model outputs and model factors, or screening methods, which only yield qualitative results. However, due to the characteristics of membrane bioreactors (MBR) (non-linear kinetics, complexity, etc.) there is an interest to adequately quantify the effects of non-linearity and interactions. This can be achieved with variance-based sensitivity analysis methods. In this paper, the Extend…

Global sensitivity analysis in ASM applications: comparison of the SRC and Extended-FAST method for a UCT-MBR model

2011

In this study global sensitivity analysis is performed to identify influential as well as non-influential parameters in a model of a University Cape Town Membrane Bioreactor (UCT-MBR). In particular, the Standardised Regression Coefficients (SRC) and Extended-FAST sensitivity analysis methods are applied. The sensitivity of model variables towards parameter variation is analysed for CODTOT, SNH4, SNO3, SPO, and MLSS along five reactor compartments. Both methods indicate that the parameters identified as being influential differ from section to section due to the different processes involved. Moreover, the relevant influence of the membrane filtration parameters is detected in the first plan…

The role of EPS in fouling and foaming phenomena occurring in an UCT-MBR pilot plant

2012

The aim of this study is to detect a possible relationship between EPS and fouling and EPS and foaming in a University Cape Town (UCT) membrane bioreactor (MBR) pilot plant. The UCT-MBR pilot plant was fed with 40 L/h of real wastewater and monitored for 165 days. Specifically physical/chemical features of influent, permeate and mixed liquor in different sections were analyzed. The fouling phenomenon was studied monitoring the hydraulic resistances of the membrane. The extracellular polymeric substances (EPSs) concentration inside the aerobic tank were also measured. The foaming phenomenon was monitored by performing the Foam Power and Scum Index testes. Results have shown a high correlatio…

Comparison between MBR and MB-MBR pilot plants subject to a gradual salinity increase: analysis of biokinetic and fouling behaviour

2014

Two pilot plants were investigated for the treatment of wastewater subject to a gradual increase of salinity. In particular, a membrane bioreactor (MBR) and a moving bed biofilm membrane bioreactor (MB-MBR) were studied. Carbon and ammonium removal, kinetic constants and membranes fouling rates have been assessed. Both plants showed very high efficiency in terms of carbon and ammonium removal and the gradual salinity increase led to a good acclimation of the biomass, as confirmed by the respirometric tests. Significant biofilm detachments from carriers were experienced, which contributed to increase the irreversible superficial cake deposition. However, this aspect prevented the pore foulin…

Advanced course: innovative wastewater treatment and mathematical modelling

2015

During the last years many advances have matured in wastewater treatment both in terms of processes and mathematical modelling approaches. For a new generation of new scientists and engineers entering/working in the wastewater treatment field, the quantity, complexity and diversity of these new developments can be overwhelming. This Advanced Course on Innovative wastewater treatment processes and mathematical modelling will provide a comprehensive overview and a discussion platform for recent advances and trends currently under development in the context of wastewater treatment. This course is aimed at professionals (Master, PhD or equivalent experience) in wastewater treatment and mathemat…

Analisi sperimentale e modellistica di formazione del fouling delle menbrane negi sistemi MBR

2012

La tecnologia MBR è una realtà consolidata e la sua applicazione è considerata una valida alternativa ai sistemi convenzionali, soprattutto ove il refluo depurato assuma pienamente il ruolo di “risorsa” riutilizzabile. Tuttavia, la diffusione dei bioreattori a membrana è frenata prevalentemente dall’elevato costo di investimento su cui grava, inoltre, l’impossibilità di prevedere correttamente la durata della vita utile delle membrane a causa dell’incompleta conoscenza del fouling, della sua evoluzione e delle sue conseguenze. Il fenomeno di sporcamento, infatti, è estremamente complesso e la conoscenza dei meccanismi di deposito e le proprietà sporcanti di tutti gli agenti presenti nella m…

Materials recovery from WEEE: current situation in Sicily.

2012

The potential recovery of materials and energy in one year in Italy and in Sicily was estimated assuming that all WEEEs were gathered through the collection – treatment – disposal system implemented according to the rules in force. The embodied energy (EE) recovery associated to material recovery was also estimated, starting from standard values of EE and from yields declared for each component. Mass fractions composition for some categories of WEEE given by a facility in Catania agree with the national averages. Starting from data given by another facility - located in Siracusa - which processes all the five R categories (R1 to R5), potential mass and energy recovery was estimated for this…

I CONSUMI ENERGETICI NEI SISTEMI MBR: VERSO UNA STRATEGIA PER UNA ATTENUAZIONE

2014

Estimation of methane emission by a municipal landfill: the case of Palermo

2010

CH4 diffuse emissions from municipal solid waste landfills represent one of the most important anthropogenic source of greenhouse-gas. CH4 is produced by anaerobic biodegradation of organic matter in land-filled MSW and it constitutes the major component of landfill gas. Gas recovery is a suitable tool to effectively control CH4 emissions from landfill sites and the quantification of CH4 emissions represents a good tool to evaluate the effectiveness of biogas recovering system in reducing biogas emission. In particular, LFG emissions can be indirectly evaluated from mass balance equations between formation, recovery and oxidation of biogas in the landfill, as well as on a direct approach ba…

Sensitivity and uncertainty analysis of a plant-wide model for carbon and energy footprint of wastewater treatment plants

2014

This paper presents the sensitivity and uncertainty analysis of a mathematical model for Greenhouse gas (GHG) and energy consumption assessment from wastewater treatment plants (WWTPs). The model is able to simultaneously describe the main biological and physical-chemical processes in a WWTP. Specifically, the mathematical model includes the main processes of the water and sludge lines influencing the methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) emissions. Further, the process energy demand and the energy recovery are also taken into account. The main objective of this paper is to analyze the key factors and sources of uncertainty influencing GHG emissions from WWTP at a pla…