Adrian Escapa

University of Leon | UNILEON · Department of Electric, Systems and Automatics Engineering

This study seeks to assess the impact that the anodic electrodeposition of graphene oxide (GO) has on the start-up process and on the development of microbial communities on the anode of BESs. The GO electrodeposited electrodes were characterised in abiotic conditions to verify the extent of the modification and were then transferred to a bioelectr...

Microbial electrolysis cells (MECs) have the potential to become a sustainable domestic wastewater (dWW) treatment system. However, new scale-up experiences are required to gain knowledge of critical issues in MEC designs. In this study we assess the ability of two twin membraneless MEC units (that are part of a modular pilot-scale MEC) to treat dW...

This work presents a multi-population dynamic model of a microbial electrolysis cell (MEC). The model describes the growth and metabolic activity of fermentative, electricigenic, methanogenic acetoclastic, and methanogenic hydrogenophilic microorganisms and is capable of simulating hydrogen production in a MEC fed with complex organic matter, such...

Microbial electrolysis cells (MECs) are cutting edge technology with great potential to become an alternative to conventional wastewater treatments (anaerobic digestion, activated sludge, etc.). One of the main features of MECs is that they allow organic matter present in wastewater to be converted into hydrogen thus helping to offset the energy co...

This study explores the possibility of utilising electrochemically assisted anaerobic digestion supplemented with carbon-based materials to stimulate methanogenesis. Two different carbonaceous materials—commercial activated carbon (AC), and pyrolysed argan (PA, derived from argan shells)—were employed as supplements, with cheese whey (CW) being use...

La educación superior necesita adaptarse constantemente a un entorno cambiante y dinámico que demanda una constante evolución en la forma de entender el proceso de enseñanza-aprendizaje, y es en este contexto que surge la innovación docente como un elemento clave para asegurar la calidad y el progreso de la educación superior y, por lo tanto, el éx...

The transition from an industrial to a knowledge-based society has increased the importance of intangible knowledge as a crucial asset for companies. In contrast, the academic world, despite being a generator and transmitter of knowledge, has been relatively passive in adapting to this change. The implementation of the European Higher Education Are...

The need to accommodate power fluctuations intrinsic to high-renewable systems will demand in the future the implementation of large quantities of energy storage capacity. Microbial electromethanogenesis (EM) can potentially absorb the excess of renewable energy and store it as CH₄. However, it is still unknown how power fluctuations impact on the...

Microbial electrosynthesis (MES), a sub-branch of bioelectrochemical processes, takes advantage of a certain type of electroactive microorganism to produce added value products (such as methane) from carbon dioxide (CO2). The aim of this study is to quantify the benefits of using a carbon felt electrode modified with reduced graphene-oxide (rgoCF)...

knowing how to calculate the magnetic field created in the air-gap of rotating electrical machines (REM) represents an essential step in understanding their operating principle. The approach followed by many manuals and classical text-books on REM involves first determining the magnetic field created by a full pitch coil (using Ampère’s Law) and ne...

A microbial electrolysis cell integrated in an anaerobic digestion system (MEC-AD) is an efficient configuration to produce methane from an exhausted vine shoot fermentation broth (EVS). The cell worked in a single-chamber two-electrode configuration at an applied potential of 1 V with a feeding ratio of 30/70 (30% EVS to 70% synthetic medium). In...

In this study we aimed to understand the impact of medium–low temperatures on the two main steps that usually comprise the electromethanogenesis (EM) process: electrothrophic hydrogenesis and hydrogenothrophic methanogenesis. Results revealed that pure CO2 could effectively be converted into a high-purity biogas (∼90:10 CH4/CO2) at 30 °C. However,...

Three-dimensional printing could provide flexibility in the design of a new generation of electrodes to be used in microbial electrochemical technologies (MET). In this work, we demonstrate the feasibility of using polylactic acid (PLA)/graphene—a common 3D-printing material—to build custom bioelectrodes. We also show that a suitable activation pro...

The concentration of solids in secondary sludge before anaerobic digestion in a wastewater treatment plant, bring about the production of a return flow, which contains high concentrations of all the common pollutant parameters. This return flow could unfavourably affect the performance of the processes and effluent quality of the waterline. Here, w...

CO2 level increase in the planet is a major concern and utilization, mitigation and transformation of CO2 in useful compounds is of great interest. This chapter points to an alternative electrochemical approach for reducing/making use of CO2 in a “greener” route, using electricity that may be generated from renewable sources (e.g. solar, wind). The...

The integration of Knowledge Management (KM) in various fields, including academia and business, has been fostered by the promotion of Information and Communication Technologies (ICTs). The aim of this study was, on the one hand, to understand the key processes of KM in students of the Faculty of Education and the School of Engineering in a Spanish...

The integration of Knowledge Management (KM) in various fields, including academia and business, has been fostered by the promotion of Information and Communication Technologies (ICTs). The aim of this study was, on the one hand, to understand the key processes of KM in students of the Faculty of Education and the School of Engineering in a Spanish...

The role of oxygen in anodic biofilms is still a matter of debate. In this study, we tried to elucidate the structure and performance of an electrogenic biofilm that develops on air-exposed, carbon felt electrodes, commonly used in bioelectrochemical systems. By simultaneously recording the current density produced by the bioanode and dissolved oxy...

The aim of this study is to evaluate the integration of microbial electrochemical technologies (MET) with anaerobic digestion (AD) to overcome AD limitations caused by propionate accumulation. The study focuses on understanding to what extent the inoculum impacts on the behaviour of the integrated systems (AD-MET) from the perspective of propionate...

The compound 2-mercaptobenzothizaole (MBT) has been frequently detected in wastewater and surface water and is a potential threat to both aquatic organisms and human health (its mutagenic potential has been demonstrated). This study investigated the degradation routes of MBT in the anode of a microbial electrolysis cell (MEC) and the involved micro...

The compound 2-mercaptobenzothizaole (MBT) has been frequently detected in wastewater and surface water and is a potential threat to both aquatic organisms and human health (its mutagenic potential has been demonstrated). This study investigated the degradation routes of MBT in the anode of a microbial electrolysis cell (MEC) and the involved micro...

Microbial Electrolysis Cells are devices capable of converting the organic fraction present in the wastewaters into hydrogen. Integrating this relatively new technology into wastewater treatment plants can improve the energy balance and result in significant savings in greenhouse gases emissions. However, there are not many studies available in the...

Microbial electrosynthesis (MES) can potentially provide a mean for storing renewable energy surpluses as chemical energy. However, the fluctuating nature of these energy sources may represent a threat to MES, as the microbial communities that develop on the biocathode rely on the continuous existence of a polarized electrode. This work assesses ho...

The aim of this study is to evaluate the integration of microbial electrochemical technologies (MET) with anaerobic digestion (AD) to overcome AD limitations caused by propionate accumulation. The study focuses on understanding to what extent the inoculum impacts on the behaviour of the integrated systems (AD-MET) from the perspective of propionate...

Bioelectrochemical systems (BES) encompass a group of bio-based technologies capable of directly converting organic matter into electricity. In these systems, which are derived from conventional electrochemical technologies, the ion exchange membrane is a key element because of its influence on the economic feasibility and performance of BES. This...

Bioelectrochemical systems (BESs) is a term that encompasses a group of novel technologies able to interconvert electrical energy and chemical energy by means of a bioelectroactive biofilm. Microbial electrosynthesis (MES) systems, which branch off from BESs, are able to convert CO2 into valuable organic chemicals and fuels. This study demonstrates...

Bioelectrochemical systems (BES) encompass a group of biobased technologies capable of directly converting organic matter into electricity. In these systems, which are derived from conventional electrochemical systems, the ion exchange membrane represents a key element because of its influence on the economic feasibility and on the performance of B...

First large-scale experiences of bioelectrochemical systems (BES) are underway. However, there is still little knowledge on how the different elements that integrate a BES behave in near real-life conditions. This paper aims at assessing the impact of long-term operation on the cation exchange membrane and on the anodic biofilm of two 16 L Microbia...

This study was aimed at understanding the effect of applied voltage, catholyte and reactor scale on nitrogen recovery from two different organic wastes (digestate and pig slurry) by means of microbial electrolysis cell (MEC) technology. For this purpose, MEC sizes of 100, 500 and 1000 mL were tested at applied voltages of 0.6, 1 and 1.4 V using eit...

Carbon dioxide (CO2) valorization for the production of different commodity chemicals is a highly desired approach to moderate CO2 emissions into the atmosphere. The versatility of microbial electrochemical technologies makes it possible to use them for carbon capture and utilization. This is mainly achieved through two novel processes, namely: mic...

Microbial electrosynthesis (MES) allow CO2 capture and utilization for the electricity-driven bioproduction of organics such as acetic acid. Such systems can be coupled to any renewable electricity supply, especially those derived from solar and wind energy. However, fluctuations or even absence of electricity may cause damages or changes in the mi...

Selecting an anodophilic consortium capable of efficient propionate degradation. • Studying the mechanisms of propionate degradation through electrochemical analysis. • Geobacter and Clostridium proved to be the key genera in successfully acclimated bioanodes. • These observations lead us to hypothesize that the electron transfer mechanism is commo...

This study aims to characterize the performance of a 150 L bioelectrochemical system-based plant, during the simultaneous carbon and nitrogen removal from several waste streams of wastewater treatment plants. The bioelectrochemical system (BES) contained five electrode pairs (operated hydraulically and electrically in parallel) and was fed with eit...

This study seeks to understand how the bacterial communities that develop on biocathodes are influenced by inocula diversity and electrode potential during start-up. Two different inocula are used: one from a highly diverse environment (river mud) and the other from a low diverse milieu (anaerobic digestion). In addition, both inocula were subjecte...

Anaerobic digestion and bioelectrochemical systems have great potential to recover energy from waste streams and help overcome common hurdles associated with this process, as integrated technologies. In this study, the benefit of integrating an electrogen-enriched bioanode in a batch anaerobic digester was explored under ambient temperature conditi...

Practical implementation of bioelectrochemical systems (BES) based technologies still demands a considerable effort to make this technology economically and technically competitive. This has led to important efforts in new materials development, searching a compromise between high efficiency and low cost features. This study seeks to assess the imp...

It can hardly be overemphasized the importance of understanding biofilm formation when aiming at developing bioelectrochemical systems. One of the main challenges comes when trying to develop controlled electrogenic cultures, especially when using environmental inocula containing a high microbial diversity and richness. This study aims at investiga...

Municipal waste management has a great impact on the sustainability of human processes and green policies, especially in urban sites. Although it could be achieved the full separation of the reusable and recyclable items and the complete elimination of the organic material present in it, many waste components must still be processed in waste treatm...

The development and practical implementation of bioelectrochemical systems (BES) requires an in-depth characterisation of their components. The electrodes, which are critical elements, are usually built from carbon-based materials due to their high specific surface area, biocompatibility and chemical stability. In this study, a simple methodology t...

The introduction of electrogens-enriched electrodes into ananaerobic digester resulted in enhanced methanogenic activity at the beginning of the tests, as well as a delay in VFA build-up.This improvement seems to be due to the presence of the electrogens-enriched electrodes, rather than electrochemical activity.

Microbial electrolysis cells (MECs) have great potential as a technology for wastewater treatment in parallel to energy production. In this study we explore the feasibility of using a low-cost, membraneless MEC for domestic wastewater treatment and methane production in both batch and continuous modes. Low-strength wastewater can be successfully tr...

This paper explores the potential of a two-stage process (fermentative + biocatalyzed electrolysis) to reduce the organic load of an industrial waste stream (cheese whey) in parallel with hydrogen production. Overall, the combined process helped to significantly reduce the chemical oxygen demand (COD) of the effluent, while producing hydrogen at a...

Globally, large amounts of electrical energy are spent every year for domestic wastewater (dWW) treatment. In the future, energy prices are expected to rise as the demand for energy resources increases and fossil fuel reserves become depleted. By using appropriate technologies, the potential chemical energy contained in the organic compounds presen...

The influence of the applied voltage (Vapp) and the hydraulic retention time (HRT) on hydrogen and methane production and the removal rate for chemical oxygen demand (COD) was studied in a membrane-less microbial electrolysis cell with a Ni-based cathode. When a synthetic effluent from a dark-fermentation process was fed continuously into the anodi...

Microbial electrolysis represents a new approach for harnessing the energy contained in the organic matter of wastewater. However, before this approach can be implemented on a practical basis, a cost-effective manufacturing process for microbial electrolysis cells (MECs) must be developed. The objective of this study is to estimate an acceptable pu...

This study investigates the influence of anode and cathode size and arrangement on hydrogen production in a membrane-less flat-plate microbial electrolysis cell (MEC). Protein measurements were used to evaluate microbial density in the carbon felt anode. The protein concentration was observed to significantly decrease with the increase in distance...

Hydrogen production from glycerol was studied in a microbial electrolysis cell (MEC) with a 250 mL anodic chamber and a gas-phase cathode. A membraneless MEC design was employed, where a graphite felt anode and gas diffusion cathode were only separated by a 0.7 mm thick highly porous synthetic fabric (J-cloth). Glycerol (fuel) was continuously fed...

A thermogravimetric (TG) and mass spectrometric (MS) study was carried out of the process of devolatilization of the organic fraction of municipal solid wastes (OFMSW) and polyethylene terephthalate (PET). This involved an analysis of the heating profiles in an inert atmosphere for each of these residues separately and for a mixture made up of half...

Various mixtures incorporating a simulated organic fraction of municipal solid wastes and blood from a poultry slaughterhouse were used as substrate in a dark fermentation process for the production of hydrogen. The individual and interactive effects of hydraulic retention time (HRT), solid content in the feed (%TS) and proportion of residues (%Blo...