Search results for "MICI"

The acid–base flow battery : Sustainable energy storage via reversible water dissociation with bipolar membranes

2020

The increasing share of renewables in electric grids nowadays causes a growing daily and seasonal mismatch between electricity generation and demand. In this regard, novel energy storage systems need to be developed, to allow large-scale storage of the excess electricity during low-demand time, and its distribution during peak demand time. Acid–base flow battery (ABFB) is a novel and environmentally friendly technology based on the reversible water dissociation by bipolar membranes, and it stores electricity in the form of chemical energy in acid and base solutions. The technology has already been demonstrated at the laboratory scale, and the experimental testing of the first 1 kW pilot pla…

EXPERIMENTAL CHARACTERIZATION OF ELECTRO-MEMBRANE PROCESSES FOR THE PRODUCTION AND STORAGE OF ENERGY

2022

Performance of the first reverse electrodialysis pilot plant for power production from saline waters and concentrated brines

2016

Abstract This work reports experimental data collected for the first time on a full-scale RED pilot plant operated with natural streams in a real environment. The plant – located in the South of Italy – represents the final accomplishment of the REAPower project ( www.reapower.eu ). A RED unit equipped with almost 50 m2 of IEMs (125 cell pairs, 44x44 cm2) was tested, using both artificial and natural feed solutions, these latter corresponding to brackish water (≈0.03 M NaClequivalent) and saturated brine (4–5 M NaClequivalent). A power output up to around 40 W (i.e. 1.6 W/m2 of cell pair) was reached using natural solutions, while an increase of 60% was observed when testing the system with…

Towards 1 kW power production in a reverse electrodialysis pilot plant with saline waters and concentrated brines

2017

Abstract Reverse electrodialysis (RED) is a promising technology to extract energy from salinity gradients, especially in the areas where concentrated brine and saline waters are available as feed streams. A first pilot-scale plant was recently built in Trapani (Italy), and tested with real brackish water and brine from saltworks. The present work focuses on the scale-up of the pilot plant, reaching more than 400 m 2 of total membrane area installed and representing the largest operating RED plant so far reported in the literature. With a nominal power capacity of 1 kW, the pilot plant reached almost 700 W of power capacity using artificial brine and brackish water, while a 50% decrease in …

Numerical prediction of flow fields in baffled stirred vessels: A comparison of alternative modelling approaches

1998

Abstract Numerical simulations of the flow field in baffled mixing tanks, based on three alternative methods, are presented and discussed. In the first method, the impeller is not explicitly simulated, and its effects are modelled by imposing suitable, empirically derived, boundary conditions to the external flow. In the second method, the whole vessel volume is divided into two concentric, partially overlapping, regions. In the inner region, containing the impeller, the flow field is simulated in the rotating reference frame of the latter, while in the outer region simulations are conducted in the reference frame of the laboratory. Information is iteratively exchanged between the two regio…

Dense solid–liquid off-bottom suspension dynamics: Simulation and experiment

2009

Dense solid–liquid off-bottom suspension inside a baffled mechanically stirred tank equipped with a standard Rushton turbine is investigated. Dynamic evolution of the suspension from start-up to steady-state conditions has been determined by both visual experiments and computational fluid dynamics (CFDs). A classical Eulerian–Eulerian multifluid model (MFM) along with the “homogeneous” k–ε turbulence model is adopted to simulate suspension dynamics. In these systems the drag inter-phase force affects both solids suspension and distribution. Therefore, different computational approaches are tested in order to compute this term. Simulation results are compared with images obtained from the re…

Feasibility of Producing Electricity, Hydrogen, and Chlorine via Reverse Electrodialysis

2022

Reverse electrodialysis (RED) is a technology to generate electricity from two streams with different salinities. While RED systems have been conventionally used for electricity generation, recent works explored combining RED for production of valuable gases. This work investigates the feasibility of producing hydrogen and chlorine in addition to electricity in an RED stack and identifies potential levers for improvement. A simplified one-dimensional model is adopted to assess the technical and economic feasibility of the process. We notice a strong disparity in typical current densities of RED fed with seawater and river water and that in typical water (or chlor-alkali) electrolysis. This …

The influence of sludge retention time on mixed culture microbial fuel cell start-ups

2017

Abstract In this work, the start-ups of air-cathode microbial fuel cells (MFCs) seeds with conventional activated sludge cultivated at different solid retention times (SRTs) are compared. A clear influence of the SRT of the inoculum was observed, corresponding to an SRT of 10 days to the higher current density exerted, about 0.2 A m −2 . This observation points out that, in this type of electrochemical device, it is recommended to use high SRT seeds. The work also points out that in order to promote an efficient start-up, it is not only necessary to use high SRT seeds, but also to feed a high COD concentration. When feeding 10,000 ppm COD and keeping SRT of 10 d differences of current densi…

Control of a fermentator for the aerobic growth of saccharomyces cerevisiae by an adaptive type-2 fuzzy logic controller

2008

I controllori a logica fuzzy (FLCs) costituiscono una facile alternativa al controllo di sistemi che hanno un comportamento fortemente non lineare, facendo uso di fuzzy sets e di una logica fuzzy del 1° tipo. A dispetto della loro popolarità però, la ricerca ha mostrato come FLCs di 1° tipo, abbiano difficoltà a gestire e a minimizzare le incertezze presenti in un sistema. Una più grande complessità dei sistemi a logica fuzzy di 2° tipo rispetto quelli del 1° tipo, permette di gestire e conseguentemente di minimizzare gli effetti di una varietà di incertezze che non può essere direttamente gestita da FLS del 1° tipo. In questo lavoro si è considerato l’uso di un FLS del 2° tipo per il contr…

Optimization study of acid-base flow battery stacks with monopolar and bipolar membranes

2021

The Acid-Base Flow Battery (AB-FB) is a novel technology for energy storage. It is based on reversible electrodialytic techniques with ion-exchange membranes. The kye elements are the bipolar membranes, which convert electrical energy in the form of pH gradients and vice versa. Despite the promising results of few experimental studies, the AB-FB potential has been poorly explored so far. This work presents an optimization study of the AB-FB. It was performed by a multi-scale process model previously developed (gPROMS Model Builder® environment) and experimentally validated. A two-objective optimization was conducted by maximizing the Net Round Trip Efficiency and the Net Power Density in th…