Sustainable Biogas Production in Municipal Wastewater Treatment Plants

This report deals with anaerobic digestion (AD) of sewage sludge, an energy- and nutrient-rich by-product of wastewater treatment plants (WWTP). The objective is to promote sustainable practices and technology, focussing on energy efficiency of biogas production and utilisation. An overview of the AD process in WWTP is given, along with standard energy performances, nutrient recycling and different process options and their impacts. However, it is by no means intended as a detailed technical guideline for project management. The report is aimed at energy policy and decision makers as well as WWTP operators and was produced by IEA Bioenergy Task 37, an expert working group that addresses challenges related to the economic and environmental sustainability of biogas production and utilisation.JRC.F.8-Sustainable Transpor

Production de spiruline à la ferme : produire de la spiruline à la ferme grâce au digestat et à la chaleur excédentaire d’une installation de biogaz

The development of projects coupling an agricultural anaerobic digestion installation with the production of spirulina is an attractive concept, since the waste streams from the methanisation and from biogas valorization can be used to produce a high value product. This principle allows a better energetic valorization of surplus heat and of exhaust gases coming from the cogeneration unit. The limits of this configuration have been evaluated for Switzerland to study if the implementation of such coupling increases the competitiveness of agricultural anaerobic digestion. The thermal autonomy of the plant has been established as the main criterion to design the spirulina production units. For different working conditions (light radiation, nutrients source, size of methanisation units), the potential production of spirulina has been evaluated. The process energy yield, the environmental impact and the process economy show that 50% of surplus heat can be valorized, being 85-90% of heat contained in the exhaust gases; that the decrease in carbon dioxide emissions is not relevant and that, for the conditions tested, the operating costs are currently too high to allow the economic feasibility of the project

Estudio comparado (Europa versus Estados Unidos) sobre el concepto de medicamento genérico

Objetivo: Determinar las similitudes y las diferencias del concepto científico de medicamento genérico en Europa y en Estados Unidos a partir de un estudio comparado de la legislación vigente en ambas regiones. Material y Método: Análisis de la legislación vigente en Europa y en Estados Unidos relativa al concepto de medicamento genérico, analizando detalladamente cada aspecto de la definición del mismo, composición (principio activo y excipientes), forma farmacéutica, características de calidad, bioequivalencia y concepto de medicamento de referencia. Estudio comparado de los resultados para concluir similitudes y diferencias en el ámbito conceptual. Resultados: Se observan similitudes y diferencias en cuanto al concepto científico de medicamento genérico en Europa y en Estados Unidos. En concreto, se observan diferencias al concepto de “mismo principio activo”, “misma forma farmacéutica”, al uso de excipientes con respecto al medicamento de referencia y a la elección del propio medicamento de referencia. También se observan diferencias en cuanto a cómo demostrar bioequivalencia con respecto al medicamento de referencia. Se observan similitudes en cuanto al concepto de “misma dosis”, características de calidad, etiquetado e indicaciones con respecto al medicamento de referencia. Conclusiones: Estas diferencias van a tener un impacto en el desarrollo, registro y comercialización del medicamento genérico que desee comercializar una compañía farmacéutica de forma global en estas regiones.Aim: The objective is to determine the similarities and differences between Europe and the United States on the scientific concept of generic medicine. The study is based on a comparative study of the current legislation in both regions. Materials and Methods: Analysis of the current legislation in Europe and the United States in reference to the concept of generic medicine, analyzing each aspect of the definition in detail: composition (active substance and excipients), pharmaceutical form, quality characteristics, bioequivalence and the concept of reference medicinal product. Comparative study of the results obtained to conclude similarities and differences on the conceptual scope. Results: Similarities and differences are observed on the scientific concept of generic medicine between Europe and the United States. In particular, differences on the concept “same active substance” and “same pharmaceutical form”, the use of excipients versus the reference medicinal product and the election of the reference medicinal product are observed. Moreover, differences on how to demonstrate bioequivalence with the reference medicinal product are also observed. Similarities on the concept of “same strength”, quality characteristics, labelling and indications versus the reference medicinal product are observed. Conclusions: These differences will have an impact on the development, registration and marketing of a generic medicine by a company which decides to market a generic medicine globally in these regions

Methanol opportunities for electricity and hydrogen production in bioelectrochemical systems

An anodic syntrophic consortium (exoelectrogenic plus fermentative bacteria) able to use methanol as sole carbon source was developed for the first time in a bioelectrochemical system. In this frame, promising results were obtained in single chamber MFC, comparable to those obtained with readily biodegradable substrates. Regarding MEC operation, the presence of homoacetogenic bacteria led to electron recycling, avoiding net hydrogen production in single chamber MEC. In a double chamber MEC, satisfying results (in terms of coulombic efficiency and cathodic gas recovery) were obtained even though energy recovery still restrained the feasibility of the process. The approach used in this work with methanol opens a new range of possibilities for other complex substrates as electron donors for bioelectrosynthesis

Obtaining microbial communities with exoelectrogenic activity from anaerobic sludge using a simplified procedure

BACKGROUND: The microbial fuel cell (MFC) technology transforms the chemical energy present in substrates into electricity. Starting-up these systems, i.e. enriching the anodic community in exoelectrogenic bacteria, is a lengthy process or requires expensive equipment. - RESULTS: An easy and low-cost procedure based on a sediment MFC was developed to select microbial communities with exoelectrogenic activity from the anaerobic sludge of a waste water treatment plant (WWTP). The configuration was based on a simple vessel working as a single chamber MFC with a cathode of stainless steel wool in the liquid surface and a submerged graphite fibre brush as anode. In 30 days of operation, a biofilm with remarkable exoelectrogenic activity was grown on the anode of the MFC. This graphite fibre brush anode was able to supply 0.9Wm-2 when working in an air-cathode MFC (AC-MFC) for 45 days. - CONCLUSION:The procedure presented was demonstrated to be a successful, low-costandlow-maintenance procedure to obtain exoelectrogenic activity and had performances comparable with other more costly and complex inoculation procedures. The Sed-MFC does not require a potentiostat, external aeration, stirring, membranes or an enriched inoculum in the exoelectrogenic biomass

Sustainable Waste-to-Energy Technologies: Bioelectrochemical Systems

The food industry produces a large amount of waste and wastewater, of which most of the constituents are carbohydrates, proteins, lipids, and organic fibers. Therefore food wastes are highly biodegradable and energy rich. Bioelectrochemical systems (BESs) are systems that use microorganisms to biochemically catalyze complex substrates into useful energy products, in which the catalytic reactions take place on electrodes. Microbial fuel cells (MFCs) are a type of bioelectrochemical systems that oxidize substrates and generate electric current. Microbial electrolysis cells (MECs) are another type of bioelectrochemical systems that use an external power source to catalyze the substrate into by-products such as hydrogen gas, methane gas, or hydrogen peroxide. BESs are advantageous due to their ability to achieve a degree of substrate remediation while generating energy. This chapter presents an extensive literature review on the use of MFCs and MECs to remediate and recover energy from food industry waste. These bioelectrochemical systems are still in their infancy state and further research is needed to better understand the systems and optimize their performance. Major challenges and limitations for the use of BESs are summarized and future research needs are identified

Diseño conceptual y desarrollo de un tren de aterrizaje para vehículos espaciales suborbitales

This work explains the conceptual design and development of a landing gear system for suborbital spacecraft. It is a project for the aerospace degree program with a focus on airports, addressing concepts of materials studied throughout the university program, as well as new concepts specific to the aerospace sector. The design takes particular emphasis on key elements such as the landing skid, transmission bars, and, most importantly, oleo-pneumatic shock absorbers. The primary objectives are focus on conducting a study for a potential realmarket prototype, assessing its feasibility and challenges. This includes deepening understanding of materials covered in the academic curriculum and extending expertise into new aerospace areas, such as oils, sealing elements, surface protection, and components related to shock absorbers. Furthermore, it involves enhancing knowledge in physics and aerodynamics to develop surfaces with low aerodynamic resistance, improve their characteristics and efficiency, and comprehend thermodynamics to understand possible reactions within the shock absorber. This includes understanding the minimum and maximum working temperatures of structural components, load-bearing capacities under buckling and longitudinal loads, pressure/volume relationships, and the impact of specific weather conditions on both structural and non-structural elements. The methodology employed is based on researching and documenting scientific articles and books related to aviation, with a focus on oil types and shock absorbers, including military standards (MIL), regulations from aviation authorities such as the Federal Aviation Administration (FAA) and the European Union Aviation Safety Agency (EASA), as well as Microsoft programs (PowerPoint and Excel) for calculations and prototype design schematics. The results have been highly satisfactory, leading to a very viable and efficient design. It has successfully produced landing gear components with appropriate lengths and diameters, offering a favourable balance between quality and cost. Safety factors have been considered, particularly in critical scenarios involving structural elements and passenger safety. In a hypothetical scenario, certification by regulatory bodies for the incorporation of this design into a real prototype has been explored

Registro de medicamentos genéricos de uso humano: Estudio jurídico comparado entre Europa y Estados Unidos

[spa] El medicamento genérico tiene un papel importante en el mercado farmacéutico debido a que proporciona medicamentos terapéuticamente equivalentes a un medicamento innovador de referencia y a precios más competitivos. La industria farmacéutica del medicamento genérico con visión internacional necesita una regulación armonizada que permita desarrollar desde el punto de vista científico y también legal un medicamento genérico global, que consecuentemente conlleven una menor utilización de recursos y un menor tiempo de acceso al mercado internacional. La regulación de medicamentos genéricos en Europa y en Estados Unidos repercute por una parte en su cumplimiento y por otra, en la evaluación que de los mismos deben efectuar las respectivas agencias sanitarias. En Europa y Estados Unidos, el medicamento se encuentra rigurosamente intervenido por la Administración. Cada uno de estos marcos regionales cuenta con su propia normativa lo que provoca una dificultad añadida al proceso de globalización del medicamento. A nivel internacional, la ICH se convierte en el punto de encuentro de las agencias reguladoras y de las compañías farmacéuticas con objeto de unificar criterios y crear un marco normativo armonizado. Este trabajo proporciona un estudio metodológico comparado y detallado de los diferentes aspectos de que consta el registro de los medicamentos genéricos en ambas regiones: la regulación de medicamentos genéricos a nivel internacional, de Europa y de Estados Unidos, la definición conceptual de medicamento genérico y medicamento de referencia en el ámbito de su desarrollo galénico, los requisitos legales que debe cumplir el medicamento genérico, las partes que componen el expediente de registro, los requisitos de calidad y de bioequivalencia de los medicamentos genéricos, los organismos oficiales que tiene competencia en materia de evaluación de dichos medicamentos y el procedimiento de registro. Este estudio comparativo detallado de la regulación de los medicamentos genéricos en Europa y en Estados Unidos permite apreciar las diferencias existentes en la actualidad entre ambas regiones y presentar una discusión final, unas conclusiones y unas propuestas orientadas a proponer modificaciones a la regulación actual de Europa y de Estados Unidos con el objetivo de construir un sistema de registro de medicamentos genéricos óptimo, eficiente y armonizado a nivel global para la mejorar la salud de todos los ciudadanos.[eng] Generic medicinal products have an important role in the pharmaceutical market due to the fact that they provide with medicinal product therapeutically equivalents to a reference innovator medicinal product but at more competitive prices. Pharmaceutical industry of generic medicines with an international vision needs an harmonised regulation which allow it the development of a global generic medicines from a scientific and legal point of view, which involves less use of resources and less time to access to the international market. The medicinal products are under rigorous regulation by the authorities of Europe and the United States. Each region has its own regulation and it is a barrier for the global process of harmonization of medicines. At the same time, the International Conference on Harmonisation (ICH) is a meeting point for the Health authorities and Pharmaceutical Industry to stimulate the creation of this harmonized regulation. This study provides a methodological comparative and detailed study of the different aspects involved in the pharmaceutical registration of a generic medicinal product in Europe and the United Stated: the regulation of the generic medicines internationally, in Europe and in the United States, the scientific definition of generic and reference medicinal products, the legal requirements which must comply a generic medicine, the parts of the registration file to submit and obtain the marketing authorization, the quality and bioequivalence requirements, the official competent authorities responsible for the assessment of generic medicines and the registration procedure. The results obtained in this comparative study shows that there are current differences between the regulation in Europe and the United States and a final discussion, conclusions and proposals are submitted with the objective to built an optimal, efficient and harmonized global pharmaceutical registration system to improve the health of all the citizens

Hydrogen production from wastewater in single chamber microbial electrolysis cells: studies towards its scaling-up

Les cel·les microbianes d’electròlisi (MEC) són sistemes biocatalitzats que ofereixen la possibilitat de valoritzar aigües residuals produint hidrogen, el qual és un bon vector energètic i un reactiu àmpliament utilitzat a la indústria química. L’aportació d’energia és necessària per a dur a terme el procés, i per tant la implementació d’aquesta tecnologia només serà possible si s’assoleix un balanç energètic positiu entre l’energia subministrada i l’energia obtinguda en forma d’hidrogen. La configuració de MEC en una sola cambra i sense membrana redueix els requeriments energètics del procés a més a més de simplificar-ne el disseny i la complexitat en l’operació, sent a priori una configuració més adient de cara a l’escalat del sistema. El principal inconvenient d’aquesta configuració és la disponibilitat de l’hidrogen per altres microorganismes, que en redueix la producció i la puresa. En aquesta tesi, es varen considerar diferents mesures per a millorar el rendiment de MEC en una sola cambra i sense membrana, amb l’objectiu d’augmentar les oportunitats d’escalat d’aquest sistema. El desenvolupament d’un biofilm exoelectrogen adequat va ser clau per a millorar l’eficiència del sistema. L’eficiència coulòmbica es va utilitzar com a paràmetre per a avaluar la inoculació de l’ànode en configuració de cel·la microbiana de combustible, estudiant els efectes de paràmetres de disseny tals com l’àrea de càtode o la resistència externa. Es va observar que una àrea de càtode òptima podria existir i que treballar a la resistència externa òptima era important. El biofilm catòdic també es va investigar, observant-ne un efecte barrera per a l’oxigen que permetia mantenir l’ànode en condicions anaeròbies. Es va observar que l’ús d’elevades resistències externes durant el procés d’inoculació afavoria electroactivitat del biofilm exoelectrogen, i es va investigar com a possible procediment de selecció que permetés créixer biomassa que fes servir de manera eficient l’aportació d’energia en MEC. En vista a l’ús de les MEC per a tractar aigües residuals reals, es va bioaugmentar el biofilm anòdic amb un consorci microbià constituït per bacteris fermentadors amb capacitat de degradar substrats complexes a compostos simples i per bacteris exoelectrògens. Per tal d’augmentar la producció i la puresa de l’hidrogen produït, es va estudiar a llarg termini una estratègia per a reduir el temps de retenció d’hidrogen al sistema i així evitar la metanogènesi en MEC d’una sola cambra. L’estratègia, que consistia en arrossegar l’hidrogen del sistema per bombolleig de nitrogen, va ser efectiva tot i que va presentar limitacions depenent del substrat consumit, indicant la necessitat de combinar aquesta estratègia amb d’altres. A més a més, es va estudiar l’ús d’una pila de combustible com a una eina econòmica de monitorització de producció biològica d’hidrogen a escala de laboratori. La senyal obtinguda correlacionava correctament amb l’hidrogen subministrat, sent tan eficient com la cromatografia de gasos. L’ús d’aquest instrument podria arribar a permetre la implementació d’estratègies de control i optimització en el procés. Finalment, es va investigar l’oportunitat de produir hidrogen del glicerol residual provinent de la indústria del biodiesel en MEC d’una sola cambra, que es veié limitada com a resultat del metabolisme de bacteris homoacetògens. El metanol, sovint contingut en el glicerol residual, es va usar de manera efectiva com a substrat en MEC. L’electrofermentació de glicerol sintètic també es va estudiar com a possible tecnologia per a valoritzar les aigües residuals de la indústria del biodiesel afavorint la producció de 1,3-propanodiol. Amb el treball desenvolupat es va concloure que l’escalat d’una MEC d’una sola cambra per a la producció d’hidrogen té opcions d’implementació si: (i) es desenvolupa un biofilm anòdic adequat, molt electroactiu i amb capacitat de tractar un rang ampli de substrats, (ii) s’usen aigües residuals amb baixa tendència a la proliferació de poblacions metanogèniques i (iii) s’opera a baix temps de retenció de l’hidrogen i baix temps de retenció hidràulic.Microbial electrolysis cells (MEC) are microbially catalyzed systems that offer the possibility to valorize wastewater by producing hydrogen, which is a valuable energy carrier and a widely used reactant in the chemical industry. Some energy input is required to drive the process, therefore real implementation of this technology will only be possible if a positive energy balance between the energy obtained as hydrogen and the energy supplied is achieved. A single chamber membrane-less configuration of MEC reduces energy requirements and design and operation complexity, being a priori a more convenient configuration for scale-up. The main drawback of a single chamber configuration is hydrogen availability for other microorganisms, which decreases hydrogen production and purity. Different approaches were taken in this thesis to increase the performance of single chamber membrane-less MEC, having the aim to increase the chances for this system to be scaled up. A proper exoelectrogenic biofilm development on the anode was key to ensure better system efficiencies. Coulombic efficiency was used to evaluate the inoculation of the anode in microbial fuel cell configuration, studying the effects of design parameters such as the area of cathode or the external resistance. It was observed that an optimal area of cathode might exist and that working at the optimal external resistance was of importance. The cathodic biofilm was also investigated, observing an oxygen barrier effect that maintained the anode in anaerobic conditions. The use of high external resistances during the inoculation process was observed to enhance the electroactivity of the exoelectrogenic biofilm, and it was also investigated as a selection procedure to allow the growth of biomass that efficiently deals with the energy input in MEC. In view of a real use of MEC treating wastewater, a consortium between fermentative bacteria that could degrade complex substrates to simpler compounds and exoelectrogenic bacteria was developed and used to bioaugment the anodic biofilm. In order to improve hydrogen production and purity, a strategy to avoid methanogenesis in single chamber MEC by reducing the hydrogen retention time was tested in the long term for both readily biodegradable synthetic wastewater and complex synthetic wastewater. The strategy, consisting in hydrogen stripping by sparging nitrogen, was effective but presented limitations depending on the complex substrate consumed, showing the need to combine it with other strategies. Also, a fuel cell was tested as a low cost monitoring tool for biohydrogen producing systems at lab scale. The signal obtained correlated well with hydrogen supplied and was as efficient as other reference analytical methodologies such as gas chromatography. The use of this device could allow the implementation of system control and optimization strategies in the process. Finally the opportunities for crude glycerol to produce hydrogen in single chamber MEC were explored, seeing that it was constraint as a result of homoacetogenic bacteria metabolism. Methanol, often contained in crude glycerol, was used effectively in MEC. Electrofermentation of synthetic glycerol was also studied as a possible technology to give an added value to biodiesel industry wastewater by enhancing the production of 1,3-propanediol. With the work developed in this thesis it was concluded that scaling up single chamber MEC for hydrogen production has opportunities if a series of strategies are addressed: (i) the development of efficient anodic biofilms, highly electroactive and with capacity to treat a wide range of compounds, (ii) the use of wastewater with low methanogenesis potential and (iii) operation at low hydrogen retention time and low hydraulic retention time

Hydrogen production from wastewater in single chamber microbial electrolysis cells: studies towards its scaling-up

Les cel·les microbianes d'electròlisi (MEC) són sistemes biocatalitzats que ofereixen la possibilitat de valoritzar aigües residuals produint hidrogen, el qual és un bon vector energètic i un reactiu àmpliament utilitzat a la indústria química. L'aportació d'energia és necessària per a dur a terme el procés, i per tant la implementació d'aquesta tecnologia només serà possible si s'assoleix un balanç energètic positiu entre l'energia subministrada i l'energia obtinguda en forma d'hidrogen. La configuració de MEC en una sola cambra i sense membrana redueix els requeriments energètics del procés a més a més de simplificar-ne el disseny i la complexitat en l'operació, sent a priori una configuració més adient de cara a l'escalat del sistema. El principal inconvenient d'aquesta configuració és la disponibilitat de l'hidrogen per altres microorganismes, que en redueix la producció i la puresa. En aquesta tesi, es varen considerar diferents mesures per a millorar el rendiment de MEC en una sola cambra i sense membrana, amb l'objectiu d'augmentar les oportunitats d'escalat d'aquest sistema. El desenvolupament d'un biofilm exoelectrogen adequat va ser clau per a millorar l'eficiència del sistema. L'eficiència coulòmbica es va utilitzar com a paràmetre per a avaluar la inoculació de l'ànode en configuració de cel·la microbiana de combustible, estudiant els efectes de paràmetres de disseny tals com l'àrea de càtode o la resistència externa. Es va observar que una àrea de càtode òptima podria existir i que treballar a la resistència externa òptima era important. El biofilm catòdic també es va investigar, observant-ne un efecte barrera per a l'oxigen que permetia mantenir l'ànode en condicions anaeròbies. Es va observar que l'ús d'elevades resistències externes durant el procés d'inoculació afavoria electroactivitat del biofilm exoelectrogen, i es va investigar com a possible procediment de selecció que permetés créixer biomassa que fes servir de manera eficient l'aportació d'energia en MEC. En vista a l'ús de les MEC per a tractar aigües residuals reals, es va bioaugmentar el biofilm anòdic amb un consorci microbià constituït per bacteris fermentadors amb capacitat de degradar substrats complexes a compostos simples i per bacteris exoelectrògens. Per tal d'augmentar la producció i la puresa de l'hidrogen produït, es va estudiar a llarg termini una estratègia per a reduir el temps de retenció d'hidrogen al sistema i així evitar la metanogènesi en MEC d'una sola cambra. L'estratègia, que consistia en arrossegar l'hidrogen del sistema per bombolleig de nitrogen, va ser efectiva tot i que va presentar limitacions depenent del substrat consumit, indicant la necessitat de combinar aquesta estratègia amb d'altres. A més a més, es va estudiar l'ús d'una pila de combustible com a una eina econòmica de monitorització de producció biològica d'hidrogen a escala de laboratori. La senyal obtinguda correlacionava correctament amb l'hidrogen subministrat, sent tan eficient com la cromatografia de gasos. L'ús d'aquest instrument podria arribar a permetre la implementació d'estratègies de control i optimització en el procés. Finalment, es va investigar l'oportunitat de produir hidrogen del glicerol residual provinent de la indústria del biodiesel en MEC d'una sola cambra, que es veié limitada com a resultat del metabolisme de bacteris homoacetògens. El metanol, sovint contingut en el glicerol residual, es va usar de manera efectiva com a substrat en MEC. L'electrofermentació de glicerol sintètic també es va estudiar com a possible tecnologia per a valoritzar les aigües residuals de la indústria del biodiesel afavorint la producció de 1,3-propanodiol. Amb el treball desenvolupat es va concloure que l'escalat d'una MEC d'una sola cambra per a la producció d'hidrogen té opcions d'implementació si: (i) es desenvolupa un biofilm anòdic adequat, molt electroactiu i amb capacitat de tractar un rang ampli de substrats, (ii) s'usen aigües residuals amb baixa tendència a la proliferació de poblacions metanogèniques i (iii) s'opera a baix temps de retenció de l'hidrogen i baix temps de retenció hidràulic.Microbial electrolysis cells (MEC) are microbially catalyzed systems that offer the possibility to valorize wastewater by producing hydrogen, which is a valuable energy carrier and a widely used reactant in the chemical industry. Some energy input is required to drive the process, therefore real implementation of this technology will only be possible if a positive energy balance between the energy obtained as hydrogen and the energy supplied is achieved. A single chamber membrane-less configuration of MEC reduces energy requirements and design and operation complexity, being a priori a more convenient configuration for scale-up. The main drawback of a single chamber configuration is hydrogen availability for other microorganisms, which decreases hydrogen production and purity. Different approaches were taken in this thesis to increase the performance of single chamber membrane-less MEC, having the aim to increase the chances for this system to be scaled up. A proper exoelectrogenic biofilm development on the anode was key to ensure better system efficiencies. Coulombic efficiency was used to evaluate the inoculation of the anode in microbial fuel cell configuration, studying the effects of design parameters such as the area of cathode or the external resistance. It was observed that an optimal area of cathode might exist and that working at the optimal external resistance was of importance. The cathodic biofilm was also investigated, observing an oxygen barrier effect that maintained the anode in anaerobic conditions. The use of high external resistances during the inoculation process was observed to enhance the electroactivity of the exoelectrogenic biofilm, and it was also investigated as a selection procedure to allow the growth of biomass that efficiently deals with the energy input in MEC. In view of a real use of MEC treating wastewater, a consortium between fermentative bacteria that could degrade complex substrates to simpler compounds and exoelectrogenic bacteria was developed and used to bioaugment the anodic biofilm. In order to improve hydrogen production and purity, a strategy to avoid methanogenesis in single chamber MEC by reducing the hydrogen retention time was tested in the long term for both readily biodegradable synthetic wastewater and complex synthetic wastewater. The strategy, consisting in hydrogen stripping by sparging nitrogen, was effective but presented limitations depending on the complex substrate consumed, showing the need to combine it with other strategies. Also, a fuel cell was tested as a low cost monitoring tool for biohydrogen producing systems at lab scale. The signal obtained correlated well with hydrogen supplied and was as efficient as other reference analytical methodologies such as gas chromatography. The use of this device could allow the implementation of system control and optimization strategies in the process. Finally the opportunities for crude glycerol to produce hydrogen in single chamber MEC were explored, seeing that it was constraint as a result of homoacetogenic bacteria metabolism. Methanol, often contained in crude glycerol, was used effectively in MEC. Electrofermentation of synthetic glycerol was also studied as a possible technology to give an added value to biodiesel industry wastewater by enhancing the production of 1,3-propanediol. With the work developed in this thesis it was concluded that scaling up single chamber MEC for hydrogen production has opportunities if a series of strategies are addressed: (i) the development of efficient anodic biofilms, highly electroactive and with capacity to treat a wide range of compounds, (ii) the use of wastewater with low methanogenesis potential and (iii) operation at low hydrogen retention time and low hydraulic retention time