Analysis of Biomass Characteristics in MBR and MB-MBR Systems Fed with Synthetic Wastewater: Influence of a Gradual Salinity Increase

The paper presents the results of a field gathering campaign carried out on two different pilot scale membrane bioreactor (MBR) systems, treating synthetic wastewater subject to a gradual increase of salinity. One was a conventional MBR system, while the other was a moving bed biofilm membrane bioreactor (MB-MBR), which combines suspended biomass and biofilm. Indeed, the presence of suspended carriers inside the bioreactor seems to give benefits due to the collisions between the circulating media and the membrane. The aim of the study was the comparison of two configurations in terms of biomass activity characterization and performance (pollutants removal and hydraulic behaviour). The resul…

CONFRONTO TRA UN MODELLO DINAMICO ED UNO STAZIONARIO NELLA VALUTAZIONE DELLE PERDITE REALI ED APPARENTI DI UNA RETE DI DISTRIBUZIONE

Nel presente articolo è stato applicato un modello dinamico di simulazione idraulica delle reti di distribuzione per la valutazione delle perdite idriche reali ed apparenti. Sono stati sviluppati uno modello di domanda al nodo che simula i serbatoi privati ed un modulo per la stima delle perdite apparenti. Le perdite reali sono state modellate attraverso una relazione generale che esprime la portata effluente dalla perdita come una funzione della pressione. I risultati ottenuti sono stati confrontati con le stime modellistiche basate su di un approccio stazionario.

PUMP AS TURBINE (PAT) IN INTERMITTENT DISTRIBUTION NETWORKS

A hydraulic model was performed in order to evaluate potential energy recovery resulting by the use of centrifugal pump as turbines (PAT) in the water distribution network characterized by the presence of private tanks. The model integrates the Enhanced Global Gradient Algorithm (EGGA) (Todini [1], Giustolisi et al. [2]), with a pressure driven model (Criminisi et al. [3]) that entails a more realistic representation of the influence of the private tanks filling and emptying process in the network behaviour. The model was applied to real case study: a district metered area in Palermo (Italy). Namely three different scenarios were analyzed and compared with the actual scenario (Scenario 0 - …

Role of modeling uncertainty in the estimation of climate and socioeconomic impact on river water quality. J. of Water Resources Planning and Management – Asce, 138(5), 479–490.

Climate is one of the most important factors leading to changes in the hydrologic and environmental characteristics of river basins. When considering water quality, the natural factors should be weighed against anthropogenic factors (such as urbanization, increased population, and higher water demand) that may increase or decrease the effect of climatic modifications. Any prediction of future climatic and anthropogenic scenarios is affected by uncertainty and the modelling tools that are used for evaluating their impact on receiving water bodies. The present paper is aimed at investigating the complexity of such analyses and the uncertainty related to future impact predictions based on limi…

Istituzioni di Economia Politica, Volume I, Microeconomia, Seconda edizione

Predisposizione di modelli previsionali della domanda idrica residenziale in condizioni di scarsità

Analysis of the Impact of the intermittent distribution by modelling the network filling processes.

UN MODELLO NUMERICO NON STAZIONARIO PER LO STUDIO DEI FENOMENI TRANSITORI DURANTE IL RIEMPIMENTO DELLE RETI DI DISTRIBUZIONE IDRICA: ANALISI DELLA RESISTENZA IN MOTO NON UNIFORME

Ability of software SWMM to simulate sewer smooth pressurization transient

As a consequence of heavy rainfall events or network malfunctioning, filling of sewers (pressurization) and network overflowing may occur. Several models are commonly used to simulate floods in drainage networks and their results are usually thought to be reliable and robust. Actually, mathematical models based on the momentum equation appear to be more suitable in correctly simulating the pressurization moving jump but models based on the energy equation are much more popular because of their greater simplicity in comparison to the former ones. In this paper, on the basis of laboratory pipe tests, the ability of software SWMM (Storm Water Management Model, probably the most popular softwar…

Notes about urban drainage systems in the ancient Rome

The magnificence of Roman buildings is very well-known from historical books, notes etc.. In contraposition to this, generally speaking, less is known about the majesty of Roman sewer systems in terms of structures, facilities and the very advanced as well as rudimental complexity. The Roman sewers have been over-praised. Indeed, despite their longevity, they ignored basic sanitary principles as well as design rules. The Roman Empire is in many ways the highest point of sewage management in the ancient world. Famous for public baths and latrines with quite complex engineering, Rome also excelled in the use of covered drains for stormwater and waste-sewage, with some houses directly connecte…

Rainwater reuse in urban areas: a mathematical model and a longterm modelling approach

Natural water resources are becoming increasingly limited due to global-scale climate change and water availability issues have become so severe that they must be addressed. Given these issues, reuse of wastewater and rainwater provides a promising way to cope with water shortages. This paper describes an investigation into the efficiency of rainwater usage systems. A conceptual model was built to assess the behaviour of rainwater tanks and their effectiveness in coping with water shortages. The study is based on a long-term simulation (12 years) of different rainwater reuse tank schemes. The associated reductions in residential freshwater demand (water reuse efficiency) and wetweather runo…

Introduction

This collection of essays is a tribute to Neri Salvadori, the man and scholar, teacher and friend, whom the scientific community owes important works in the tradition of Piero Sraffa’s revival of the classical economists’ approach to the problems of value, income distribution, capital accumulation, technical progress, scarce natural resources, economic development and growth. The essays in this book have all been freshly written and contain original work with novel ideas in the areas mentioned. In this introduction we first summarize briefly Neri Salvadori’s academic career, his work and his intellectual and organisational activities and then provide a short overview of the essays collected…

VALUTAZIONE DEI CARICHI INQUINANTI DI ORIGINE DIFFUSA E CONCENTRATA A SCALA DI BACINO: APPLICAZIONE A UN CASO DI STUDIO SICILIANO

Obiettivo della ricerca è stata la predisposizione di un modello di tipo integrato a scala di bacino al fine di ricostruire la dinamica dei carichi inquinanti concentrati di origine civile e produttiva e dei carichi diffusi di origine agricola e zootecnica, in osservanza dei nuovi criteri di gestione dei corpi idrici superficiali introdotti dalle normative nazionale ed europea (Direttiva UE 2000/60, D.lgs. 152/2006). Il modello messo a punto è stato applicato al bacino del fiume Nocella, ubicato in Sicilia e ritenuto un idoneo banco di prova in quanto recapito di numerosi scarichi in forma concentrata e diffusa. I primi derivano in modo continuo dagli impianti di depurazione a servizio di d…

MODELLAZIONE DELLA QUALITÀ DELLE ACQUE NEI RICETTORI IN TEMPO DI PIOGGIA

Data availability impact on integrated modelling reliability throughout identifiability analysis

A BASIC DECISION SUPPORT SYSTEM FOR IMPROVING SERVICE LEVEL IN INTERMITTENT WATER DISTRIBUTION SYSTEMS

EVALUATION OF DIFFUSE AND CONCENTRATED POLLUTION AT WATERSHED SCALE

The study presents an integrated approach in order to analyse and quantify pollution dynamics at basin scale depending on concentrated and diffuse sources. More specifically, an integrated model for urban drainage system has been exploited in order to simulate the complex sewer network - wastewater treatment plant and receiving water body. Moreover, a quali-quantitative model has been developped in order to simulate the non-point sources pollutant (agricultural and zoo-technical) in term of water river discharges and nutrient, produced from the wash off of soils. Finally, different models have been coupled in order to reconstruct the whole pollutant load for the receiving water body and to …

Linee guida per la gestione dell'emergenza idrica e per la pianificazione di interventi di mitigazione in ambiente urbano

Economic Theory and its History

This collection of essays is a tribute to Neri Salvadori, the man and scholar, teacher and friend, whom the scientific community owes important works in the tradition of Piero Sraffa’s revival of the classical economists’ approach to the problems of value, income distribution, capital accumulation, technical progress, scarce natural resources, economic development and growth. The essays in this book have all been freshly written and contain original work with novel ideas in the areas mentioned.