Search results for "electrodialysi"

Towards the simultaneous generation of electric energy and the abatement of organic pollutants by reverse electrodialysis processes

2012

In reverse electrodialysis (RED) processes, electrical energy is directly extracted from chemical potential gradients arising from salinity differences, especially from sea and river water [1]. In RED there are at least four complementary elements: (1) electrodes, where electron transfer reactions occur to allow the transformation of the charge carrier from ion to electron; (2) ion selective exchange membranes, which allow the selective transport of ions; (3) solvents, which make a continuum for ion transport; (4) electrolytes, i.e. the current carriers between cathode and anode. The redox process is usually chosen in order to limit the energetic losses, the cost of redox specie and electro…

REVERSE ELECTRODIALYSIS PROCESSES FOR THE PRODUCTION OF CHEMICALS AND THE TREATMENT OF CONTAMINATED WASTEWATER

ABATEMENT OF POLLUTANTS IN AQUEOUS SOLUTIONS BY REVERSE ELECTRODIALYSIS PROCESSES

2013

Electrochemistry-based technologies are very promising methods for treating wastewaters containing organic and inorganic pollutants that are either resistant to biological processes or toxic for microorganisms [1]. On the other hand, in the reverse electrodialysis (RED), the electrical energy is directly extracted from chemical potential gradients arising from salinity differences [2], especially between brine solution and sea water. RED can be potentially used for the simultaneous generation of electrical energy and the treatment of waters contaminated by recalcitrant pollutants. The advantages of using the RED process for such dual purpose are: the utilization of a green reagent such as t…

Investigation of electrode material – redox couple systems for reverse electrodialysis processes. Part II: Experiments in a stack with 10–50 cell pai…

2013

Abstract The performances of reverse electrodialysis depend on several factors, including the nature of the electrode material and of the redox processes adopted to make possible the conversion between chemical potential and electric power. In this paper the possible utilization of various redox processes (reduction/oxidation of iron species, oxidation and reduction of water, oxidation of chlorine and reduction of water) was studied in a stack equipped with 10–50 cell pairs and by focused electrolyses in a three compartment cell. The effect of selected redox processes on power density output and eventual contamination of saline solutions flowing in the stack was evaluated in detail. The eff…

Coupling electrodialysis desalination with photovoltaic and wind energy systems for energy storage: Dynamic simulations and control strategy

2020

Abstract The presence of desalination systems in polygeneration facilities is usually limited by important difficulties in operating under non-stationary regimes typical of renewable energy sources. Reverse osmosis, namely the most common desalination technology, is characterised by slow dynamics that rarely adapts to the power fluctuations of renewables. Therefore, the possibility of using electrodialysis coupled with a hybrid photovoltaic/wind energy source was investigated in this work. In particular, the combination of photovoltaic and wind energy is very attractive in order to achieve a more stable energy production, while electrodialysis is claimed to be a more flexible process compar…

Application of reverse electrodialysis to site-specific types of saline solutions: A techno-economic assessment

2019

Abstract Salinity gradients are a non-conventional source of renewable energy based on the recovery of the Gibbs free energy related to the mixing of solutions at different concentrations. Reverse Electrodialysis is a promising and innovative technology able to convert this energy directly into electric current. The worldwide availability of salinity gradients is limited to those locations where water bodies at different salinity levels are present. The present work analyses a number of different scenarios worldwide, in locations where salinity gradients are naturally available or generated by anthropogenic activities. A techno-economic model of the Reverse Electrodialysis process is presen…

An application of Reverse ElectroDialysis: energy production from produced water

2022

Techno-economic evaluation of Reverse Electrodialysis process in different real environments

2018

Salinity Gradient Power is a promising renewable energy source based on the recovery of the chemical potential released from the mixing of solutions at different concentrations. Natural salinity gradients are extensively available worldwide in natural reservoirs. Reverse Electrodialysis is an innovative technology able to perform a direct conversion of the energy of mixing into electricity. Salinity gradients coming from natural resources or from human activities are worldwide available. In the present work a number of different scenarios, including natural resources (e.g. rivers, seas, lakes and salt ponds), industrial/urban wastes (e.g. brine and treated wastewaters) are analysed. The aim…

Thermal regeneration of ammonium bi-carbonate solutions for closed-loop reverse electrodialysis

2016

Reverse electrodialysis is a novel technology that exploits a salinity gradient to generate electrical energy. The salinity gradient can be available from natural waters such as seawater and river water or they can be artificially generated and used within closed-loop applications. This last option has been recently investigated leading to the development of the RED heat engine concept. In this case, the deployed salinity gradient exiting the RED unit is regenerated in a thermally-driven unit using low-temperature heat, thus being able to convert heat to power within an integrated system. Among the different regeneration alternatives, the use of thermolytic salts has been presented as a pro…

Reverse Electrodialysis with brackish water and concentrated brines: up-scaled pilot plant operating in a real environment

2015

This work focuses on the saling up of the REA Power plant through the installation of two larger RED modules