L’attuale condizione che caratterizza il settore energetico richiede un necessario processo di riconversione che, oltre a favorire il risparmio energetico, riduca la dipendenza dai combustibili fossili ed accresca l’impiego di fonti energetiche rinnovabili, dando un contributo fondamentale alla riduzione delle emissioni di gas serra come diversi accordi internazionali richiedono. Si rende pertanto necessario accelerare i processi che da alcuni anni stanno favorendo l’utilizzo di energia da fonti rinnovabili. Tra queste, le fonti legate ai processi di trattamento biologico dei reflui stanno avendo un interessante sviluppo. Esistono numerosi processi biologici che consentono la produzione di energia in maniera indiretta, quali ad esempio i processi di digestione anaerobica finalizzati alla produzione di biogas e/o produzione biologica di idrogeno. In tale contesto si inserisce la tecnologia delle Microbial Fuel Cell, che consente la produzione diretta di energia elettrica, finalizzata al recupero energetico inteso al miglioramento dell’efficienza energetica e alla riduzione dei costi d’esercizio di impianti di trattamento biologico dei reflui. Il presente lavoro di Tesi di Dottorato sperimentale, svoltosi in collaborazione al laboratorio PROT.-IDR. della sede ENEA di Bologna, riporta i risultati dell’attività di ricerca condotta su una MFC (Microbial Fuel Cell) a doppio stadio biologico per il trattamento di reflui ad elevato carico organico e produzione continua di energia elettrica. E’ stata provata l’applicabilità della MFC con entrambi i comparti biotici utilizzando elettrodi di grafite non trattata ottenendo, con un carico organico in ingresso di circa 9 gd-1, valori di potenza massima prodotta che si attestano su 74 mWm-2, corrente elettrica massima generata di 175 mAm-2 ad una tensione di 421 mV, ed una conversione di COD in elettricità pari a 1,2 gCODm-2d-1. I risultati sono stati molto positivi per quanto riguarda le prestazioni depurative ottenute dalla MFC. L’efficienza di depurazione misurata ha raggiunto un valore massimo del 98% di rimozione del COD in ingresso, mentre e la concentrazione di azoto ammoniacale nell’effluente raccolto all’uscita del sedimentatore è sempre stata inferiore a 1 mgN-NH4+l-1. Tra gli obiettivi posti all’inizio della sperimentazione si è rivelata di notevole interesse la valutazione del possibile utilizzo della MFC come sistema per il monitoraggio on-line del COD e degli acidi grassi volatili (VFA) prodotti all’interno di un digestore anaerobico, attraverso la definizione di una correlazione tra i dati elettrici registrati in continuo e le concentrazioni di CODanaer e VFA misurate in diversi periodi della sperimentazione. L’analisi DGGE della biomassa catodica ha fornito uno strumento analitico utile allo studio della diversità della comunità microbica sospesa ed adesa al catodo e ha confermato la forte similarità delle specie batteriche riconosciute nei campioni analizzati. In particolare, le bande di sequenziamento ottenute sono affiliate ai gruppi batterici Firmicutes, -Proteobacteria,  -Proteobacteria, -Proteobacteria e Bacteroidetes. Da quanto emerso dalla sperimentazione condotta si può pertanto concludere che ad oggi le MFC sono in fase di evoluzione rispetto ai primi prototipi utilizzati per lo studio delle comunità microbiali e per la comprensione dei meccanismi di trasferimento elettronico. Sfruttarne la potenza prodotta in maniera commerciale diviene una grande sfida per il futuro, ed è opinione comune che le prime applicazioni pratiche delle MFC saranno come fonte di recupero energetico per i dispositivi utilizzati per il monitoraggio dell’ambiente e per il trattamento delle acque reflue.

In questa Tesi di Dottorato di Ricerca sono state studiate le caratteristiche strutturali e le relative prestazioni dei sistemi strutturali cellulari a pareti tozze di tipo sandwich in c. a. gettato in opera realizzate con la tecnologia del pannello di supporto in polistirene. Tali sistemi strutturali sono caratterizzati da numerose peculiarità; infatti, (i) il comportamento globale delle strutture risulta essere di tipo cellulare, e, le pareti che costituiscono il sistema resistente alle azioni sia orizzontali che verticali risultano essere: (ii) tozze, (iii) di tipo sandwich e caratterizzate da: (iv) basse percentuali di armatura, (v) ridotti tassi di lavoro a sforzo assiale e (vi) stesso quantitativo di armatura orizzontale e verticale. Date le specificità dei sistemi strutturali in esame, si è, in primo luogo, cercato di inquadrare le peculiarità strutturali sopra elencate nell’ambito scientifico. Ciò ha consentito di riscontrare una profonda carenza nella conoscenza relativa al comportamento di tali strutture specialmente nei confronti delle azioni orizzontali di tipo sismico. Pertanto i due principali obiettivi di questa Tesi di Dottorato sono stati: (1) la sistematizzazione scientifica e la relativa interpretazione di 10 anni di prove sperimentali condotte sul sistema strutturale in esame; e (2) la progettazione, la realizzazione e l’interpretazione preliminare dei risultati di una prova su tavola vibrante di una struttura a tre piani con pianta rettangolare, realizzata con la tecnologia del pannello di supporto in polistirene (la prova è stata effettuata nell’ambito del progetto di ricerca Europeo SERIES). Questa ricerca ha dunque consentito di far luce sul comportamento (in particolar modo, nei confronti delle azioni orizzontali di tipo sismico) dei sistemi strutturali composti da pareti tozze di tipo sandwich in c. a. gettato in opera realizzati con la tecnologia del pannello di supporto in polistirene. / In this Ph.D. Thesis the structural characteristics and the corresponding performances of cellular structural systems composed of cast in situ concrete walls created using the technique of the polystyrene support panel have been studied. Such structural systems are characterized by many peculiarities; in fact, (i) the overall behavior of the structures is cellular; and, the walls, which composed the vertical and the lateral resisting system, are (ii) squat, (iii) sandwich and characterized by: (iv) light amount of reinforcement, (v) low values of vertical stresses, (vi) the same amount of vertical and horizontal reinforcement. Given the specific characteristics of the structural system at hand, first of all, all these peculiarities have been set in a scientific background. As a result, a deep lack of knowledge about the structural behavior (especially with respect to lateral seismic forces) of these structures has been discovered. For this reason the main objectives of this Ph.D. Thesis are (1) the scientific systematization and the corresponding interpretation of 10 years of experimental test performed on the structural system at hand; and (2) the design, the realization and the preliminary interpretation of the results of a shaking table test carried out on a 3-story structure composed of cast in situ sandwich concrete walls (it is part of the European Research Project SERIES). This research has allowed to understand the structural behavior of the structural systems composed of cast in situ sandwich concrete walls, especially with respect to lateral seismic forces.

With the aim to provide people with sustainable options, engineers are ethically required to hold the safety, health and welfare of the public paramount and to satisfy society's need for sustainable development. The global crisis and related sustainability challenges are calling for a fundamental change in culture, structures and practices. Sustainability Transitions (ST) have been recognized as promising frameworks for radical system innovation towards sustainability. In order to enhance the effectiveness of transformative processes, both the adoption of a transdisciplinary approach and the experimentation of practices are crucial. The evolution of approaches towards ST provides a series of inspiring cases which allow to identify advances in making sustainability transitions happen. In this framework, the thesis has emphasized the role of Transition Engineering (TE). TE adopts a transdisciplinary approach for engineering to face the sustainability challenges and address the risks of un-sustainability. With this purpose, a definition of Transition Technologies is provided as a valid instruments to contribute to ST. In the empirical section, several transition initiatives have been analysed especially at the urban level. As a consequence, the model of living-lab of sustainability has crucially emerged. Living-labs are environments in which innovative technologies and services are co-created with users active participation. In this framework, university can play a key role as learning organization. The core of the thesis has concerned the experimental application of transition approach within the School of Engineering and Architecture of University of Bologna at Terracini Campus. The final vision is to realize a living-lab of sustainability. Particularly, a Transition Team has been established and several transition experiments have been conducted. The final result is not only the improvement of sustainability and resilience of the Terracini Campus, but the demonstration that university can generate solutions and strategies that tackle the complex, dynamic factors fuelling the global crisis.

It is going to be evaluated the availability of the MC process, particularly the Sweeping Gas Membrane Distillation (SGMD), to perform the regeneration of ammonium dihydrogen phosphate (ADP) from diammonium phosphate (DAP) and the study of the main parameters to perform the scale up of the process to an industrial level. Making focus on the selection and characterization of suitable membranes for the process and the design-development of SGMD pilot plant and test for the evaluation of the operative parameters. The main requirement for the MC technology application is bank on suitable membranes for the process. This must act as a barrier for one of the phases on contact and should enable the mass transport of volatile components. For operative reasons is preferable to hold back the aqueous phase, making the use of hydrophobic membranes imperative. The hydrophobic membrane character of the membranes is a critical argument for the MC process and is one of the main drawback for the massive application of this technology. Many studies to evaluate the hydrophobic character have been performed and continues to be a trend topic on the MC scenario. However few studies have been done to evaluate the variation of the hydrophobicity with the temperature and none of them to evaluate the effect of temperature above the normal water boiling point.

The increase in energy costs and the demands for products with greater nutritional value and of processing procedures less toxic to the environment are attractive factors for transferring membrane processing to food industry and biotechnology applications. Sugar production is one of the most energy-intensive applications in the food industry, therefore membrane separation processes find many applications, nevertheless some limitation exist for application of membrane processes in the sugar industry. This study focused on Food applications of membrane processes. A critical summary of a wide experimental investigation is reported. In this work, separation performances of commercial polyamide NF membranes are investigated in a wide range of compositions in the feed side at temperatures from 30 to 50°C; aqueous solutions containing monosaccharides, disaccharides, and mixtures of them are studied, and the role of the electrolytes on their rejection is investigated. All the results obtained, have been organized in three main sections: (i) Hydraulic permeability, (ii) experimental investigation as it is, and (iii) Intrinsic membrane performances. Differently from literature, where typically aqueous solutions containing monosaccharides and oligosaccharides are used at low concentrations, at room temperature and only experimental data as it is are reported, a key point of this study is the critical evaluation based on intrinsic membrane performances. The data processing discussed allows to introduce a revised Donnan Steric Pore & Dielectric Exclusion model. The revised model provides useful elements to understand which kind of interactions (complex formation or dehydration) can affect sugars rejections in presence of strong electrolytes, however dehydration effects caused by temperature and electrolyte are the most evident. The revised model is able to predict with good confidence both the temperature effect on membrane performances and rejections in multicomponent mixtures, ranging from laboratory to process/industrial scale.

The object of this PhD work is the study of innovative, composite and nanostructured polymeric materials for membrane-based separation and removal of CO2 from gaseous streams. The research on gas separation membranes, in the last two decades was largely devoted to the synthesis and fabrication of new, multiphasic materials, such as copolymers, composite materials bearing fillers dispersed in the polymeric matrix, or functionalized materials having selective functional groups attached to the polymer backbone. The materials investigated in this thesis can be divided in three classes: copolyetherimides: copolymers formed by a glassy polyimide phase, composite membranes, commonly defined as Mixed Matrix Membranes, functionalized materials obtained by chemically attaching amine moieties to a polymeric backbone for the instauration, in appropriate operative conditions, of the facilitated transport mechanism of CO2. All the above materials have the advantage that their transport properties, in terms of solubility, diffusivity and thus of gas permeability and selectivity, can be tuned and adjusted for the practical purpose. To this end, in this work, an experimental campaign devoted to the measurement of transport properties will be supported by a modeling approach on the continuous scale, for better understanding mass transport properties and the influence of material formulation on them, and develop easily accessible models for the prediction of materials behavior.

La bonifica di acquiferi contaminati è una pratica che oggi dispone di diverse soluzioni a livello tecnologico, caratterizzate tuttavia da costi (ambientali ed economici) e problematiche tecniche di entità tale da rendere in alcuni casi poco conveniente la realizzazione dell’intervento stesso. Per questo motivo sempre maggiore interesse viene rivolto nell’ambito della ricerca alle tecnologie di bioremediation, ovvero sistemi in cui la degradazione degli inquinanti avviene ad opera di microorganismi e batteri opportunamente selezionati e coltivati. L’impiego di queste tecniche consente un minor utilizzo di risorse ed apparati tecnologici per il raggiungimento degli obiettivi di bonifica rispetto ai sistemi tradizionali. Il lavoro di ricerca presentato in questa tesi ha l’obiettivo di fornire, tramite l’utilizzo della metodologia LCA, una valutazione della performance ambientale di una tecnologia di bonifica innovativa (BEARD) e due tecnologie largamente usate nel settore, una di tipo passivo (Permeable Reactive Barrier) ed una di tipo attivo (Pump and Treat con Carboni Attivi). / At the present day, remediation of polluted groundwater can be performed through various technologies; however, these technologies are often associated with relevant costs (both economic and environmental) and technical issues which in some cases may affect the cost effectiveness and feasibility of remediation itself. This is why efforts in the field of research are being increasingly focused in the developement of bioremediation technologies which use the degrading potential of bacteria and microorganism to remove target pollutants. These technologies require a smaller demand for resources and technical equipment in order to achieve clean up targets compared to traditional systems. The aim of my research work is to provide an assessment of the environmental performance trough LCA methodology of an innovative bioremediation technology (BEARD) and two widespread remediation technologies, a Permeable Reactive Barrier (passive technology) and a Pump and treat system (active technology).

Gas separation membranes of high CO2 permeability and selectivity have great potential in both natural gas sweetening and carbon dioxide capture. Many modified PIM membranes results permselectivity above Robinson upper bound. The big problem that should be solved for these polymers to be commercialized is their aging through time. In high glassy polymeric membrane such as PIM-1 and its modifications, solubility selectivity has more contribution towards permselectivity than diffusivity selectivity. So in this thesis work pure and mixed gas sorption behavior of carbon dioxide and methane in three PIM-based membranes (PIM-1, TZPIM-1 and AO-PIM-1) and Polynonene membrane is rigorously studied. Sorption experiment is performed at different temperatures and molar fraction. Sorption isotherms found from the experiment shows that there is a decrease of solubility as the temperature of the experiment increases for both gases in all polymers. There is also a decrease of solubility due to the presence of the other gas in the system in the mixed gas experiments due to competitive sorption effect. Variation of solubility is more visible in methane sorption than carbon dioxide, which will make the mixed gas solubility selectivity higher than that of pure gas solubility selectivity. Modeling of the system using NELF and Dual mode sorption model estimates the experimental results correctly Sorption of gases in heat treated and untreated membranes show that the sorption isotherms don’t vary due to the application of heat treatment for both carbon dioxide and methane. But there is decrease in the diffusivity coefficient and permeability of pure gases due to heat treatment. Both diffusivity coefficient and permeability decreases with increasing of heat treatment temperature. Diffusivity coefficient calculated from transient sorption experiment and steady state permeability experiment is also compared in this thesis work. The results reveal that transient diffusivity coefficient is higher than steady state diffusivity selectivity.

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