Advanced oxidation process models for optimisation and decision making support in water management

The objective of this thesis is contributing to the development of a systematic modelling approach for a more efficient and sustainable water management. The main aim is introducing Chemical and Process System Engineering methods and tools to provide a contribution to the AOPs (Advanced Oxidation Processes) investigation field by proposing process models that can be exploited to progress towards efficient management strategies for practical AOPs operation and inclusion in wastewater treatment networks. First, different advanced oxidation processes, namely Fenton, photo-Fenton and VUV photo-oxidation, were investigated and compared for the treatment of paracetamol (PCT) aqueous solution, by evaluating a series of performance indicators. Among the selected AOPs, VUV photo-oxidation and photo-Fenton showed the most promising results. Both processes allowed attaining total removal of the target compound and high mineralization levels. The second and main part of the thesis was focused on transforming “data into knowledge” by proposing different modelling approaches. The modelling effort focused on Fenton/photo-Fenton processes that showed the need of improving operating conditions. Accordingly, two practical kinetic models for Fenton and photo-Fenton degradation of organic compounds have been proposed and validated: • A conventional First Principles Model, based on a line source radiation model with spherical and isotropic emission, developed for the prediction of Fenton and photo-Fenton degradation of PCT and the oxidant (H2O2) consumption; • A general non-conventional First Principles Model, based on a wide-ranging contaminant degradation mechanism considering a variable number of carbon atoms for the characterization of the intermediates. Both models were experimentally validated and showed that were able to satisfactorily reproduce the system behavior. Particularly, the non-conventional First Principles Model showed to be a successful modelling approach for the Fenton/photo-Fenton degradation of different wastewater systems composed by single or multiple organic contaminants by means of lumped parameters (e.g. Total Organic Carbon-TOC). Thus, the approach proved to offer practical characterization of complex mixtures of chemicals. Once process models are proposed and validated, they can be systematically exploited to determine efficient operation modes or design alternatives. Accordingly, the thesis addressed two cases of practical interest: the optimization of a control recipe and the design of a treatment network. Particularly, a dynamic optimization framework for taking advantage of available kinetic models and determining the best hydrogen peroxide dosage profile, was proposed. Economic and environmental objectives and constraints were included to develop a dynamic optimization problem that was implemented in JModelica and solved using a direct simultaneous optimization method (IPOPT). Finally, the combination of cheaper conventional biological processes with more expensive AOPs was explored. A Mixed-Integer Non Linear Programming (MINLP) model for the optimization of a general wastewater network was proposed based on a superstructure of alternative designs, which was implemented and solved in GAMS. The novel formulation includes the BOD5/COD ratio method, describing the removal efficiency of BOD5 and COD of a treatment for modelling the variation of the biodegradability of the influents. This novel formulation allows determining the extent of the AOP treatments when combined with biological treatments, and paves the way for more complex models aimed at solving the trade-off between cost and treatment efficiency.El objetivo de esta tesis es contribuir al desarrollo de técnicas de modelado sistemático para una gestión del agua eficiente y sostenible. El objetivo principal es contribuir a la investigación de los PAOs (Procesos Avanzados de Oxidación). La tesis introduce métodos y herramientas de Ingeniería de Procesos Químicos y propone modelos que puedan ser explotados para producir estrategias eficientes de gestión y operación de los PAOs, así como para la integración de estos PAOs en redes de tratamiento de aguas residuales. Primero, se investigaron diferentes PAOs. Se consideraron los procesos Fenton, foto-Fenton y la foto-oxidación VUV, y se compararon en el tratamiento de soluciones acuosas de paracetamol (PCT) adoptando una serie de indicadores de rendimiento (Key Performance Indicators, KPI). Entre los PAOs seleccionados, la foto-oxidación VUV y foto-Fenton producieron los resultados más prometedores, permitiendo lograr la eliminación total del contaminante y alto nivel de mineralización. La segunda parte de la tesis se centró en transformar ¿datos en conocimiento¿ mediante la propuesta de modelos para los procesos Fenton / photo-Fenton con el fin de mejorar las condiciones operativas de los mismos. En concreto se han propuesto y validado dos modelos cinéticos que describen la degradación de compuestos orgánicos por procesos Fenton y foto-Fenton: ¿ Un Modelo de Principios Básicos (F convencional, que incluye la modelización de la radiación lineal con emisión esférica e isotrópica, desarrollado para predecir la degradación Fenton y foto-Fenton del PCT y el consumo de oxidante (H2O2); ¿ Un Modelo de Principios Básicos no convencional, que propone un mecanismo de degradación de contaminantes general puesto que considera el número de átomos de carbono del contaminante como la variable de partida para la propuesta de fragmentación y consiguiente generación de intermedios. Ambos modelos se validaron experimentalmente y mostraron reproducir satisfactoriamente el comportamiento del sistema. En particular, el Modelo de Principios Básicos no convencional genero resultados prometedores para la degradación Fenton / foto-Fenton de diferentes sistemas (compuestos por uno o más contaminantes orgánicos) por medio de parámetros globales (como el Carbono Orgánico Total). Por tanto, este enfoque ofrece un modelado práctico independiente del contaminante y válido para mezclas complejas de productos químicos. Una vez propuestos y validados, los modelos de proceso se pueden utilizar sistemáticamente para determinar modos de operación eficientes o alternativas de diseño. En consecuencia, la tesis se dirigió a dos casos de interés práctico: la optimización de una receta de control y el diseño de una red de tratamiento. En el primer caso, se propuso una estrategia de optimización dinámica para aprovechar los modelos cinéticos disponibles y determinar el mejor perfil de dosificación de peróxido de hidrógeno. Se incluyeron objetivos y limitaciones económicas y ambientales para desarrollar un problema de optimización dinámica que se implementó en JModelica y se resolvió utilizando un método de optimización simultánea directa (IPOPT). Finalmente, se exploró la combinación de procesos biológicos convencionales, más baratos, con PAOs, más costosos. Se propuso un modelo de Programación no Lineal de Enteros Mixtos (MINLP) para la optimización de una red general de aguas residuales, basado en una superestructura de diseños alternativos, que se implementó y resolvió en GAMS. La nueva formulación incluye la relación BOD5 / COD, que describe la eficiencia de eliminación de BOD5 y COD de un tratamiento con el fin de modelar la variación de la biodegradabilidad de los influentes. Esta novedosa formulación permite determinar el alcance de los tratamientos de PAOs cuando se combinan con tratamientos biológicos, y allana el camino para modelos más complejos destinados a resolver el equilibrio entre coste y eficiencia del tratamiento.L'objectiu d'aquesta tesi és contribuir al desenvolupament de tècniques de modelatge sistemàtic per a una gestió de l'aigua eficient i sostenible. L'objectiu principal és contribuir a la investigació dels PAOs (Processos Avançats d'Oxidació). La tesi introdueix mètodes i eines d'Enginyeria de Processos Químics i proposa models que puguin ser explotats per produir estratègies eficients de gestió i operació dels PAOs, així com per a la integració d'aquests PAOs en xarxes de tractament d'aigües residuals. Primer, es van investigar diferents PAOs. Es van considerar els processos Fenton, foto-Fenton i la foto-oxidació VUV, i es van comparar en el tractament de solucions aquoses de paracetamol (PCT) adoptant una sèrie d'indicadors de rendiment (Key Performance Indicators, KPI). Entre els PAOs seleccionats, la foto-oxidació VUV i foto-Fenton van produir els resultats més prometedors, permetent aconseguir l'eliminació total del contaminant i alt nivell de mineralització. La segona part de la tesi es va centrar en transformar "dades en coneixement" mitjançant la proposta de models per als processos Fenton / photo-Fenton amb la finalitat de millorar les condicions operatives dels mateixos. En concret, s’han proposat i validat dos models cinètics que descriuen la degradació de compostos orgànics per processos Fenton i foto-Fenton: • Un model de Principis Bàsics convencional, que inclou la modelització de la radiació lineal amb emissió esfèrica i isotròpica, desenvolupat per predir la degradació Fenton i foto-Fenton del PCT i el consum d'oxidant (H2O2); • Un model de Principis Bàsics no convencional que proposa un mecanisme de degradació de contaminants general, ja que considera el nombre d'àtoms de carboni del contaminant com la variable de partida per a la proposta de fragmentació i consegüent generació d'intermedis. Tots dos models es van validar experimentalment i van mostrar la seva capacitat de reproduir satisfactòriament el comportament del sistema. En particular, el Model de Principis Bàsics no convencional ha generat resultats prometedors per a la degradació Fenton / foto-Fenton de diferents sistemes (compostos per un o més contaminants orgànics) per mitjà de paràmetres globals (com el Carboni Orgànic Total). Per tant, aquest enfocament ofereix un modelatge pràctic, independent del contaminant i vàlid per a mescles complexes de productes químics. Un cop proposats i validats, els models de procés es poden utilitzar sistemàticament per determinar maneres d'operació eficients o alternatives de disseny. En conseqüència, la tesi es va dirigir a dos casos d'interès pràctic: l'optimització d'una recepta de control i el disseny d'una xarxa de tractament. En el primer cas, es va proposar una estratègia d'optimització dinàmica per aprofitar els models cinètics disponibles i determinar el millor perfil de dosificació de peròxid d'hidrogen. Es van incloure objectius i limitacions econòmiques i ambientals per desenvolupar un problema d'optimització dinàmica que es va implementar en JModelica i es va resoldre utilitzant un mètode d'optimització simultània directa (IPOPT). Finalment, es va explorar la combinació de processos biològics convencionals, més barats, amb PAOs, més costosos. Es va proposar un model de Programació No Lineal Entera Mixta (MINLP) per a l'optimització d'una xarxa general d'aigües residuals, basat en una superestructura de dissenys alternatius, que es va implementar i resoldre en GAMS. La nova formulació inclou la relació BOD5 / COD, que descriu l'eficiència d'eliminació de BOD5 i COD d'un tractament per tal de modelar la variació de la biodegradabilitat dels influents. Aquesta nova formulació permet determinar l'abast dels tractaments de PAOs quan es combinen amb tractaments biològics, i aplana el camí per a models més complexos destinats a resoldre l'equilibri entre cost i eficiència del tractament.L'obiettivo della presente tesi è contribuire allo sviluppo di tecniche di modellizzazione sistematica finalizzate ad una gestione efficiente e sostenibile delle risorse idriche. L'obiettivo principale è contribuire allo studio dei POA (Processi di Ossidazione Avanzata). La tesi introduce metodi e strumenti dell’ingegneria dei processi chimici e propone modelli che possano servire per lo sviluppo di strategie efficaci di gestione dei POA nonché per l'integrazione di questi ultimi nelle reti di trattamento delle acque reflue. In primo luogo, sono stati studiati diversi POA. Nello specifico, sono stati studiati i processi di foto-ossidazione Fenton, photo-Fenton e VUV per il trattamento di soluzioni acquose di paracetamolo (PCT) la cui efficacia è stata confrontata adottando una serie di indicatori di prestazione (Key Performance Indicators, KPI). Tra i POA selezionati, la foto-ossidazione VUV e il processo photo-Fenton hanno prodotto i risultati più promettenti, consentendo di ottenere l'eliminazione totale del contaminante e un alto livello di mineralizzazione. La seconda parte della tesi si è concentrata sulla trasformazione dei "dati in conoscenza" proponendo modelli finalizzati alla descrizione dei processi Fenton / photo-Fenton e con l’obiettivo ultimo di adoperarli per ottimizzare le condizioni operative di questi ultimi. In particolare, sono stati proposti e validati due modelli cinetici che descrivono la degradazione dei composti organici per mezzo dei processi Fenton e photo-Fenton: • Un modello convenzionale, che include la modellizzazione della radiazione basata sull’ipotesi di radiazione lineare ed emissione sferica e isotropica, e in grado di prevedere la degradazione del PCT ad opera dei processi Fenton e photo-Fenton nonché il consumo di ossidante (H2O2); • Un modello non convenzionale, che propone un meccanismo generale di degradazione degli inquinanti basato sul numero di atomi di carbonio del contaminante da degradare a partire dal quale si propone un meccanismo di frammentazione di quest’ultimo con conseguente generazione di prodotti intermedi. Entrambi i modelli sono stati validati sperimentalmente e hanno mostrato prestazioni soddisfacenti. In particolare, il modello non convenzionale ha mostrato di poter rappresentare la degradazione Fenton e photo-Fenton di diversi composti organici attraverso l’utilizzo di un parametro globale (come il carbonio organico totale) e qindi di offrire una proposta di modellizzazione pratica indipendente dal contaminante e che può pertanto essere adottata in caso di miscele complesse di prodotti chimici. Una volta proposti e convalidati, i modelli di processo possono essere utilizzati sistematicamente per determinare modalità operative efficienti o alternative di progettazione. Di conseguenza, la tesi ha affrontato due casi di interesse pratico: l'ottimizzazione della ricetta di controllo del processo e la progettazione di una rete di trattamento di acque reflue. Nel primo caso è stata proposta una strategia di ottimizzazione dinamica per sfruttare i modelli cinetici disponibili e determinare il miglior profilo di dosaggio del perossido di idrogeno. Sono stati inclusi obiettivi e limiti economici e ambientali per sviluppare un problema di ottimizzazione dinamica implementato in JModelica che è stato risolto utilizzando un metodo di ottimizzazione simultanea diretta (IPOPT). Infine, è stata esplorata la combinazione di processi biologici convenzionali, più economici, con i PAO, più costosi. È stato proposto un modello MINLP (Nonlinear Mixed Integer Programming) per l'ottimizzazione di una rete di acque reflue, basato su una struttura attraverso la quale è possibile rappresentare scelte progettuali alternative, che è stato implementato e risolto in GAMS. La nuova formulazione include il rapporto BOD5 / COD, che descrive l'efficienza di eliminazione di BOD5 e COD di un trattamento al fine di modellare la variazione della biodegradabilità degli influenti. Questa nuova formulazione consente di determinare le diverse possibilità di combinazione dei PAO con i trattamenti biologici e apre la strada a modelli più complessi volti a risolvere l'equilibrio tra costo ed efficienza del trattamento

Advanced oxidation process models for optimisation and decision making support in water management

Aplicat embargament des de la data de defensa fins a l'abril de 2019The objective of this thesis is contributing to the development of a systematic modelling approach for a more efficient and sustainable water management. The main aim is introducing Chemical and Process System Engineering methods and tools to provide a contribution to the AOPs (Advanced Oxidation Processes) investigation field by proposing process models that can be exploited to progress towards efficient management strategies for practical AOPs operation and inclusion in wastewater treatment networks. First, different advanced oxidation processes, namely Fenton, photo-Fenton and VUV photo-oxidation, were investigated and compared for the treatment of paracetamol (PCT) aqueous solution, by evaluating a series of performance indicators. Among the selected AOPs, VUV photo-oxidation and photo-Fenton showed the most promising results. Both processes allowed attaining total removal of the target compound and high mineralization levels. The second and main part of the thesis was focused on transforming “data into knowledge” by proposing different modelling approaches. The modelling effort focused on Fenton/photo-Fenton processes that showed the need of improving operating conditions. Accordingly, two practical kinetic models for Fenton and photo-Fenton degradation of organic compounds have been proposed and validated: • A conventional First Principles Model, based on a line source radiation model with spherical and isotropic emission, developed for the prediction of Fenton and photo-Fenton degradation of PCT and the oxidant (H2O2) consumption; • A general non-conventional First Principles Model, based on a wide-ranging contaminant degradation mechanism considering a variable number of carbon atoms for the characterization of the intermediates. Both models were experimentally validated and showed that were able to satisfactorily reproduce the system behavior. Particularly, the non-conventional First Principles Model showed to be a successful modelling approach for the Fenton/photo-Fenton degradation of different wastewater systems composed by single or multiple organic contaminants by means of lumped parameters (e.g. Total Organic Carbon-TOC). Thus, the approach proved to offer practical characterization of complex mixtures of chemicals. Once process models are proposed and validated, they can be systematically exploited to determine efficient operation modes or design alternatives. Accordingly, the thesis addressed two cases of practical interest: the optimization of a control recipe and the design of a treatment network. Particularly, a dynamic optimization framework for taking advantage of available kinetic models and determining the best hydrogen peroxide dosage profile, was proposed. Economic and environmental objectives and constraints were included to develop a dynamic optimization problem that was implemented in JModelica and solved using a direct simultaneous optimization method (IPOPT). Finally, the combination of cheaper conventional biological processes with more expensive AOPs was explored. A Mixed-Integer Non Linear Programming (MINLP) model for the optimization of a general wastewater network was proposed based on a superstructure of alternative designs, which was implemented and solved in GAMS. The novel formulation includes the BOD5/COD ratio method, describing the removal efficiency of BOD5 and COD of a treatment for modelling the variation of the biodegradability of the influents. This novel formulation allows determining the extent of the AOP treatments when combined with biological treatments, and paves the way for more complex models aimed at solving the trade-off between cost and treatment efficiency.El objetivo de esta tesis es contribuir al desarrollo de técnicas de modelado sistemático para una gestión del agua eficiente y sostenible. El objetivo principal es contribuir a la investigación de los PAOs (Procesos Avanzados de Oxidación). La tesis introduce métodos y herramientas de Ingeniería de Procesos Químicos y propone modelos que puedan ser explotados para producir estrategias eficientes de gestión y operación de los PAOs, así como para la integración de estos PAOs en redes de tratamiento de aguas residuales. Primero, se investigaron diferentes PAOs. Se consideraron los procesos Fenton, foto-Fenton y la foto-oxidación VUV, y se compararon en el tratamiento de soluciones acuosas de paracetamol (PCT) adoptando una serie de indicadores de rendimiento (Key Performance Indicators, KPI). Entre los PAOs seleccionados, la foto-oxidación VUV y foto-Fenton producieron los resultados más prometedores, permitiendo lograr la eliminación total del contaminante y alto nivel de mineralización. La segunda parte de la tesis se centró en transformar ¿datos en conocimiento¿ mediante la propuesta de modelos para los procesos Fenton / photo-Fenton con el fin de mejorar las condiciones operativas de los mismos. En concreto se han propuesto y validado dos modelos cinéticos que describen la degradación de compuestos orgánicos por procesos Fenton y foto-Fenton: ¿ Un Modelo de Principios Básicos (F convencional, que incluye la modelización de la radiación lineal con emisión esférica e isotrópica, desarrollado para predecir la degradación Fenton y foto-Fenton del PCT y el consumo de oxidante (H2O2); ¿ Un Modelo de Principios Básicos no convencional, que propone un mecanismo de degradación de contaminantes general puesto que considera el número de átomos de carbono del contaminante como la variable de partida para la propuesta de fragmentación y consiguiente generación de intermedios. Ambos modelos se validaron experimentalmente y mostraron reproducir satisfactoriamente el comportamiento del sistema. En particular, el Modelo de Principios Básicos no convencional genero resultados prometedores para la degradación Fenton / foto-Fenton de diferentes sistemas (compuestos por uno o más contaminantes orgánicos) por medio de parámetros globales (como el Carbono Orgánico Total). Por tanto, este enfoque ofrece un modelado práctico independiente del contaminante y válido para mezclas complejas de productos químicos. Una vez propuestos y validados, los modelos de proceso se pueden utilizar sistemáticamente para determinar modos de operación eficientes o alternativas de diseño. En consecuencia, la tesis se dirigió a dos casos de interés práctico: la optimización de una receta de control y el diseño de una red de tratamiento. En el primer caso, se propuso una estrategia de optimización dinámica para aprovechar los modelos cinéticos disponibles y determinar el mejor perfil de dosificación de peróxido de hidrógeno. Se incluyeron objetivos y limitaciones económicas y ambientales para desarrollar un problema de optimización dinámica que se implementó en JModelica y se resolvió utilizando un método de optimización simultánea directa (IPOPT). Finalmente, se exploró la combinación de procesos biológicos convencionales, más baratos, con PAOs, más costosos. Se propuso un modelo de Programación no Lineal de Enteros Mixtos (MINLP) para la optimización de una red general de aguas residuales, basado en una superestructura de diseños alternativos, que se implementó y resolvió en GAMS. La nueva formulación incluye la relación BOD5 / COD, que describe la eficiencia de eliminación de BOD5 y COD de un tratamiento con el fin de modelar la variación de la biodegradabilidad de los influentes. Esta novedosa formulación permite determinar el alcance de los tratamientos de PAOs cuando se combinan con tratamientos biológicos, y allana el camino para modelos más complejos destinados a resolver el equilibrio entre coste y eficiencia del tratamiento.L'objectiu d'aquesta tesi és contribuir al desenvolupament de tècniques de modelatge sistemàtic per a una gestió de l'aigua eficient i sostenible. L'objectiu principal és contribuir a la investigació dels PAOs (Processos Avançats d'Oxidació). La tesi introdueix mètodes i eines d'Enginyeria de Processos Químics i proposa models que puguin ser explotats per produir estratègies eficients de gestió i operació dels PAOs, així com per a la integració d'aquests PAOs en xarxes de tractament d'aigües residuals. Primer, es van investigar diferents PAOs. Es van considerar els processos Fenton, foto-Fenton i la foto-oxidació VUV, i es van comparar en el tractament de solucions aquoses de paracetamol (PCT) adoptant una sèrie d'indicadors de rendiment (Key Performance Indicators, KPI). Entre els PAOs seleccionats, la foto-oxidació VUV i foto-Fenton van produir els resultats més prometedors, permetent aconseguir l'eliminació total del contaminant i alt nivell de mineralització. La segona part de la tesi es va centrar en transformar "dades en coneixement" mitjançant la proposta de models per als processos Fenton / photo-Fenton amb la finalitat de millorar les condicions operatives dels mateixos. En concret, s’han proposat i validat dos models cinètics que descriuen la degradació de compostos orgànics per processos Fenton i foto-Fenton: • Un model de Principis Bàsics convencional, que inclou la modelització de la radiació lineal amb emissió esfèrica i isotròpica, desenvolupat per predir la degradació Fenton i foto-Fenton del PCT i el consum d'oxidant (H2O2); • Un model de Principis Bàsics no convencional que proposa un mecanisme de degradació de contaminants general, ja que considera el nombre d'àtoms de carboni del contaminant com la variable de partida per a la proposta de fragmentació i consegüent generació d'intermedis. Tots dos models es van validar experimentalment i van mostrar la seva capacitat de reproduir satisfactòriament el comportament del sistema. En particular, el Model de Principis Bàsics no convencional ha generat resultats prometedors per a la degradació Fenton / foto-Fenton de diferents sistemes (compostos per un o més contaminants orgànics) per mitjà de paràmetres globals (com el Carboni Orgànic Total). Per tant, aquest enfocament ofereix un modelatge pràctic, independent del contaminant i vàlid per a mescles complexes de productes químics. Un cop proposats i validats, els models de procés es poden utilitzar sistemàticament per determinar maneres d'operació eficients o alternatives de disseny. En conseqüència, la tesi es va dirigir a dos casos d'interès pràctic: l'optimització d'una recepta de control i el disseny d'una xarxa de tractament. En el primer cas, es va proposar una estratègia d'optimització dinàmica per aprofitar els models cinètics disponibles i determinar el millor perfil de dosificació de peròxid d'hidrogen. Es van incloure objectius i limitacions econòmiques i ambientals per desenvolupar un problema d'optimització dinàmica que es va implementar en JModelica i es va resoldre utilitzant un mètode d'optimització simultània directa (IPOPT). Finalment, es va explorar la combinació de processos biològics convencionals, més barats, amb PAOs, més costosos. Es va proposar un model de Programació No Lineal Entera Mixta (MINLP) per a l'optimització d'una xarxa general d'aigües residuals, basat en una superestructura de dissenys alternatius, que es va implementar i resoldre en GAMS. La nova formulació inclou la relació BOD5 / COD, que descriu l'eficiència d'eliminació de BOD5 i COD d'un tractament per tal de modelar la variació de la biodegradabilitat dels influents. Aquesta nova formulació permet determinar l'abast dels tractaments de PAOs quan es combinen amb tractaments biològics, i aplana el camí per a models més complexos destinats a resoldre l'equilibri entre cost i eficiència del tractament.L'obiettivo della presente tesi è contribuire allo sviluppo di tecniche di modellizzazione sistematica finalizzate ad una gestione efficiente e sostenibile delle risorse idriche. L'obiettivo principale è contribuire allo studio dei POA (Processi di Ossidazione Avanzata). La tesi introduce metodi e strumenti dell’ingegneria dei processi chimici e propone modelli che possano servire per lo sviluppo di strategie efficaci di gestione dei POA nonché per l'integrazione di questi ultimi nelle reti di trattamento delle acque reflue. In primo luogo, sono stati studiati diversi POA. Nello specifico, sono stati studiati i processi di foto-ossidazione Fenton, photo-Fenton e VUV per il trattamento di soluzioni acquose di paracetamolo (PCT) la cui efficacia è stata confrontata adottando una serie di indicatori di prestazione (Key Performance Indicators, KPI). Tra i POA selezionati, la foto-ossidazione VUV e il processo photo-Fenton hanno prodotto i risultati più promettenti, consentendo di ottenere l'eliminazione totale del contaminante e un alto livello di mineralizzazione. La seconda parte della tesi si è concentrata sulla trasformazione dei "dati in conoscenza" proponendo modelli finalizzati alla descrizione dei processi Fenton / photo-Fenton e con l’obiettivo ultimo di adoperarli per ottimizzare le condizioni operative di questi ultimi. In particolare, sono stati proposti e validati due modelli cinetici che descrivono la degradazione dei composti organici per mezzo dei processi Fenton e photo-Fenton: • Un modello convenzionale, che include la modellizzazione della radiazione basata sull’ipotesi di radiazione lineare ed emissione sferica e isotropica, e in grado di prevedere la degradazione del PCT ad opera dei processi Fenton e photo-Fenton nonché il consumo di ossidante (H2O2); • Un modello non convenzionale, che propone un meccanismo generale di degradazione degli inquinanti basato sul numero di atomi di carbonio del contaminante da degradare a partire dal quale si propone un meccanismo di frammentazione di quest’ultimo con conseguente generazione di prodotti intermedi. Entrambi i modelli sono stati validati sperimentalmente e hanno mostrato prestazioni soddisfacenti. In particolare, il modello non convenzionale ha mostrato di poter rappresentare la degradazione Fenton e photo-Fenton di diversi composti organici attraverso l’utilizzo di un parametro globale (come il carbonio organico totale) e qindi di offrire una proposta di modellizzazione pratica indipendente dal contaminante e che può pertanto essere adottata in caso di miscele complesse di prodotti chimici. Una volta proposti e convalidati, i modelli di processo possono essere utilizzati sistematicamente per determinare modalità operative efficienti o alternative di progettazione. Di conseguenza, la tesi ha affrontato due casi di interesse pratico: l'ottimizzazione della ricetta di controllo del processo e la progettazione di una rete di trattamento di acque reflue. Nel primo caso è stata proposta una strategia di ottimizzazione dinamica per sfruttare i modelli cinetici disponibili e determinare il miglior profilo di dosaggio del perossido di idrogeno. Sono stati inclusi obiettivi e limiti economici e ambientali per sviluppare un problema di ottimizzazione dinamica implementato in JModelica che è stato risolto utilizzando un metodo di ottimizzazione simultanea diretta (IPOPT). Infine, è stata esplorata la combinazione di processi biologici convenzionali, più economici, con i PAO, più costosi. È stato proposto un modello MINLP (Nonlinear Mixed Integer Programming) per l'ottimizzazione di una rete di acque reflue, basato su una struttura attraverso la quale è possibile rappresentare scelte progettuali alternative, che è stato implementato e risolto in GAMS. La nuova formulazione include il rapporto BOD5 / COD, che descrive l'efficienza di eliminazione di BOD5 e COD di un trattamento al fine di modellare la variazione della biodegradabilità degli influenti. Questa nuova formulazione consente di determinare le diverse possibilità di combinazione dei PAO con i trattamenti biologici e apre la strada a modelli più complessi volti a risolvere l'equilibrio tra costo ed efficienza del trattamento.Postprint (published version

Experimental tests on a new harvesting system for Burley tobacco

The globalization of the tobacco production has led to a drop in competitiveness of the Italian tobacco on the world market. Burley is the main variety of tobacco cropped in Campania region of Southern Italy. Its leaves have to be sewn, in the curing phase. Aim of this work is to show the results of the implementation of a new harvest machine prototype. Basically, the machine used for Bright tobacco, totally mechanical harvested, which doesn’t need to be sewn because it requires an indirect-fire treatment into the curing furnaces. The machine was modified in order to mechanize harvesting of Burley tobacco, and tested on four cultivars of Burley tobacco under three different planting layouts. The Burley tobacco leaves can be harvested mechanically by pulling individual leaves off the stalk; leaves are then sorted and tied in bundles prior to sewing. A mechanical burley tobacco harvesting system was evaluated. This machine consists in realizing a leaves orientation system based on the different weight between the leaf blade and the stalk enhanced by an air flow. The measurements taken were harvest timing, work capacity, and quality standards of the work carried out. The results, in terms of user time, range from 6.67 h/ha to 7.80 h/ha while in terms of operational efficiency are between 88% and 89%. The average user capacity recorded for the four cultivars is equal to 0.14 ha/h, a value far from the one recorded for the same harvesting machine used for Bright tobacco (0.25 ha/h). The harvest timing capacity, range from 0.51 t/h to 0.99 t/h. The work productivity goes from 0.17 t to 0.33 t per hour of human unit respectively. The average number of detached leaves, depending on the cultivar, has been between 523 and 744. Concerning the leaf orientation, a general percentage of 73% was achieved

Systematic optimization approach for the efficient management of the photo-Fenton treatment process

The photo-Fenton process is a photochemical process that has proved to be highly efficient in degrading new potentially harmful contaminants. Despite of this, scarce attention has been paid to the development of systematic procedures and optimisation strategies to efficiently operate such a process. The present work aims at investigating the effectiveness of a model-based approach in carrying out the dynamic optimisation of the recipe of a photo-Fenton process, performed in fed-batch mode (reactant dosage). This work has addressed and solved multiple optimisation problems, searching for the optimal hydrogen peroxide (H2O2) dosage profile, and Pareto frontiers have been built accordingly in order to point out the interaction between three main process efficiency parameters, such as processing time, total amount of H2O2 used, and Total Organic Carbon (TOC) removal. Such a study allows mapping the best operating conditions and provides a decision-making oriented overview of the process. An economic study has also been carried out with the aim of finding out the optimal H2O2 dosage profile that guarantees the minimum operating cost under a varying set of operational and environmental constraints, such as TOC removal. This work has adopted and properly adapted the model by Cabrera Reina et al. (2012) in order to describe the evolution of the system under a flexible reactant dosage. Cabrera Reina et al. (2012) proposed a semi-empirical kinetic model to track paracetamol degradation using the photo-Fenton process and experimentally validated this model for a pollutant load range between 4 and 25¿mmol L-1 of TOC (e.g. industrial wastewaters). Dynamic optimisation has been addressed applying a direct simultaneous optimisation method using this extended model. Results have been presented and discussed in regard of optimal H2O2 dosage under both economic and environmental constraints. The model-based optimisation approach has allowed a fast practical recipe adjustment with reduced experimental work.Peer ReviewedPreprin

Stima del fabbisogno e della spesa long term-care in Italia: valutazioni ex-ante di una proposta di riforma

Questo rapporto intende contribuire all’analisi e discussione sulla riforma del sistema italiano di long-term care (LTC) attraverso una stima della spesa necessaria a finanziare la nuova Prestazione Universale per la Non Autosufficienza, prevista dall’articolo 4 della legge 33/2023. Il rapporto è articolato in tre parti. La prima fornisce una stima sintetica della spesa necessaria all’implementazione della Prestazione Universale a partire da come questa è stata disegnata nella legge. Le parti successive presentano le relazioni tecniche. La seconda parte presenta una stima dell’entità del fabbisogno assistenziale a cui la Prestazione Universale dovrebbe rispondere. La terza parte illustra nel dettaglio i contenuti della stima economica

Removal of Paracetamol Using Effective Advanced Oxidation Processes

Fenton, photo-Fenton, and photo-induced oxidation, were investigated and compared for the treatment of 0.26 mmol L-1 of paracetamol (PCT) in a deionised water matrix, during a reaction span of 120.0 min. Low and high Fenton reagent loads were studied. Particularly, the initial concentration of Fe2+ was varied between 0.09 and 0.18 mmol L-1 while the initial concentration of H2O2 was varied between 2.78 and 11.12 mmol L-1. The quantitative performance of these treatments was evaluated by: (i) measuring PCT concentration; (ii) measuring and modelling TOC conversion, as a means characterizing sample mineralization; and (iii) measuring cytotoxicity to assess the safe application of each treatment. In all cases, organic matter mineralization was always partial, but PCT concentration fell below the detection limit within 2.5 and 20.0 min. The adopted semi-empirical model revealed that photo induced oxidation is the only treatment attaining total organic matter mineralization (¿MAX= 100% in 200.0 min) at the expense of the lowest kinetic constant (k = 0.007 min-1). Conversely, photo-Fenton treatment using high Fenton reagent loads gave a compromise solution (¿MAX= 73% and k = 0.032 min-1). Finally, cytotoxicity assays proved the safe application of photo-induced oxidation and of photo-Fenton treatments using high concentrations of Fenton reagents.Peer ReviewedPostprint (published version

Kinetic model of photo-Fenton degradation of paracetamol in an annular reactor: main reaction intermediates and cytotoxicity studies

A kinetic model derived from a simplified reaction sequence is proposed for the photo-Fenton degradation of Paracetamol (PCT), employing an annular photoreactor. The kinetic model explicitly included the effects of radiation absorption on pollutant degradation kinetics through the evaluation of the Local Volumetric Rate of Photon Absorption (LVRPA). Irradiated experiments achieved an average PCT conversion of 99.3% at 5 min of reaction, and a maximum of 69% of mineralization. Conversely, non-irradiated experiments reached an average PCT conversion of 86.6% at 5 min of reaction, and a maximum of 35% of mineralization. Kinetic parameters (, ,M-1s-1) were estimated employing a nonlinear, multi-parameter regression method, and the validated kinetic model was used to predict temporal variations of the concentrations of HP, PCT, and the main reaction intermediates: hydroquinone (HQ) and 1,4-benzoquinone (BQ). The root mean square error (RMSE) values obtained for HP, PCT, HP, HQ and BQ were 1.16¿×¿10-2, 7.13¿×¿10-1, 3.53¿×¿10-3, 3.05¿×¿10-3 mM, respectively, showing a good agreement between experimental and predicted data. Moreover, the kinetic model was validated with a new set of experimental tests, confirming its predictive capacity. Beyond the degree of mineralization attained, additional cytotoxicity tests proved that the photo-Fenton process is effective in generating a non-toxic effluent under the operating variables investigated.Peer ReviewedPostprint (published version

Safety, Immunogenicity and Dose Ranging of a New Vi-CRM197 Conjugate Vaccine against Typhoid Fever: Randomized Clinical Testing in Healthy Adults

Typhoid fever causes more than 21 million cases of disease and 200,000 deaths yearly worldwide, with more than 90% of the disease burden being reported from Asia. Epidemiological data show high disease incidence in young children and suggest that immunization programs should target children below two years of age: this is not possible with available vaccines. The Novartis Vaccines Institute for Global Health developed a conjugate vaccine (Vi-CRM₁₉₇) for infant vaccination concomitantly with EPI vaccines, either starting at 6 weeks with DTP or at 9 months with measles vaccine. We report the results from a Phase 1 and a Phase 2 dose ranging trial with Vi-CRM₁₉₇ in European adults.Following randomized blinded comparison of single vaccination with either Vi-CRM₁₉₇ or licensed polysaccharide vaccines (both containing 25·0 µg of Vi antigen), a randomised observer blinded dose ranging trial was performed in the same center to compare three concentrations of Vi-CRM₁₉₇ (1·25 µg, 5·0 µg and 12·5 µg of Vi antigen) with the polysaccharide vaccine.All vaccines were well tolerated. Compared to the polysaccharide vaccine, Vi-CRM₁₉₇ induced a higher incidence of mild to moderate short lasting local pain. All Vi-CRM₁₉₇ formulations induced higher Vi antibody levels compared to licensed control, with clear dose response relationship.Vi-CRM₁₉₇ did not elicit safety concerns, was highly immunogenic and is therefore suitable for further clinical testing in endemic populations of South Asia.ClinicalTrials.gov NCT01123941 NCT01193907

Age-dependent acquisition of IgG antibodies to Shigella serotypes—a retrospective analysis of seroprevalence in Kenyan children with implications for infant vaccination

BackgroundShigellosis mainly affects children under 5 years of age living in low- and middle-income countries, who are the target population for vaccination. There are, however, limited data available to define the appropriate timing for vaccine administration in this age group. Information on antibody responses following natural infection, proxy for exposure, could help guide vaccination strategies.MethodsWe undertook a retrospective analysis of antibodies to five of the most prevalent Shigella serotypes among children aged <5 years in Kenya. Serum samples from a cross-sectional serosurvey in three Kenyan sites (Nairobi, Siaya, and Kilifi) were analyzed by standardized ELISA to measure IgG against Shigella sonnei and Shigella flexneri 1b, 2a, 3a, and 6. We identified factors associated with seropositivity to each Shigella serotype, including seropositivity to other Shigella serotypes.ResultsA total of 474 samples, one for each participant, were analyzed: Nairobi (n = 169), Siaya (n = 185), and Kilifi (n = 120). The median age of the participants was 13.4 months (IQR 7.0–35.6), and the male:female ratio was 1:1. Geometric mean concentrations (GMCs) for each serotype increased with age, mostly in the second year of life. The overall seroprevalence of IgG antibodies increased with age except for S. flexneri 6 which was high across all age subgroups. In the second year of life, there was a statistically significant increase of antibody GMCs against all five serotypes (p = 0.01–0.0001) and a significant increase of seroprevalence for S. flexneri 2a (p = 0.006), S. flexneri 3a (p = 0.006), and S. sonnei (p = 0.05) compared with the second part of the first year of life. Among all possible pairwise comparisons of antibody seropositivity, there was a significant association between S. flexneri 1b and 2a (OR = 6.75, 95% CI 3–14, p < 0.001) and between S. flexneri 1b and 3a (OR = 23.85, 95% CI 11–54, p < 0.001).ConclusionChildren living in low- and middle-income settings such as Kenya are exposed to Shigella infection starting from the first year of life and acquire serotype-specific antibodies against multiple serotypes. The data from this study suggest that Shigella vaccination should be targeted to infants, ideally at 6 or at least 9 months of age, to ensure children are protected in the second year of life when exposure significantly increases

L’accoglienza socio-educativa dei MSNA e dei neomaggiorenninella pandemia da Covid 19

Il contributo presentato riprende i risultati della prima fase diunaricerca su Msna e Tutori volontari assumendo la traumaticità determinata dall’esperienza del Covid-19 come necessario concetto sensibilizzante (Blumer, 1969), rivedendo l’impianto metodologico e determinando la messa a punto di prospettive e strumenti in divenire. Attraverso uno studio di caso che prevede interviste a Tutori volontari, Msna, neomaggiorenni, coordinatori di comunità ed educatori, si è inteso indagare come le reti relazionali e istituzionali abbiano elaborato strategie di tutela e prevenzione di povertà educative e deprivazioni socio-affettive in emergenza