Search results for "ELECTROCHEMICAL SYSTEM"
showing 5 items of 5 documents
Heat-to-current conversion of low-grade heat from a thermocapacitive cycle by supercapacitors
2015
Thermal energy is abundantly available, and especially low-grade heat is often wasted in industrial processes as a by-product. Tapping into this vast energy reservoir with cost-attractive technologies may become a key element for the transition to an energy-sustainable economy and society. We propose a novel heat-to-current converter which is based on the temperature dependence of the cell voltage of charged supercapacitors. Using a commercially available supercapacitor, we observed a thermal cell-voltage rise of around 0.6 mV K-1 over a temperature window of 0 degrees C to 65 degrees C. Within our theoretical model, this can be used to operate a Stirling-like charge-voltage cycle whose eff…
Electrical power production from low-grade waste heat using a thermally regenerative ethylenediamine battery
2017
Abstract Thermally regenerative ammonia-based batteries (TRABs) have been developed to harvest low-grade waste heat as electricity. To improve the power production and anodic coulombic efficiency, the use of ethylenediamine as an alternative ligand to ammonia was explored here. The power density of the ethylenediamine-based battery (TRENB) was 85 ± 3 W m−2-electrode area with 2 M ethylenediamine, and 119 ± 4 W m−2 with 3 M ethylenediamine. This power density was 68% higher than that of TRAB. The energy density was 478 Wh m−3-anolyte, which was ∼50% higher than that produced by TRAB. The anodic coulombic efficiency of the TRENB was 77 ± 2%, which was more than twice that obtained using ammon…
Effect of mode of operation, substrate and final electron acceptor on single-chamber membraneless microbial fuel cell operating with a mixed community
2018
Abstract Waste minimization and circular thinking are to be achieved in order to cope with the limited amount of resources of our planet. In this perspective, bio-electrochemical systems (BESs) can contribute to the global balance with their ability to extract chemical residual energy from wastewater and transform it directly into electrical current. BESs development has been limited by the cost connected to reactor design, in which membranes and cathode catalyst constituted a major drawback. In this paper we report the optimization process of a simple reactor without membranes or precious catalyst that produced 47.1 mW m−2, which is more than what achieved with configurations including mem…
BIO-ELECTROCHEMICAL SYSTEMS FOR ENERGY GATHERING FROM WASTEWATER
2017
It has been calculated that annually 1.5 × 108 MWh are wasted as municipal, industrial, and animal wastewater. The recovery of at least part of this energy it is of primary importance in order to approach circular economy. As AD, MFC is a biotechnology that uses microorganism into an anaerobic environment for energy conversion and recovery. Differently from AD, MFC belongs to the sub-division of Bio-Electrochemical Systems (BESs), having the advantage to achieve a direct electrical output. Exoelectrogens bacteria are employed, capable to close their respiratory electron chain on the surface of an electrode. Up to know, BESs were used to extract energy from a multitude of wastes, such as dis…
Electricity Production from Yeast Wastewater in Membrane-Less Microbial Fuel Cell with Cu-Ag Cathode
2023
Wastewater has high potential as an energy source. Therefore, it is important to recover even the smallest part of this energy, e.g., in microbial fuel cells (MFCs). The obtained electricity production depends on the process rate of the electrodes. In MFC, the microorganisms are the catalyst, and the cathode is usually made of carbon material (e.g., with the addition of Pt). To increase the MFC efficiency (and reduce costs by reducing use of the noble metals), it is necessary to search the new cathode materials. In this work, the electricity production from yeast wastewater in membrane-less microbial fuel cells with Cu-Ag cathode was analyzed. In the first place, the measurements of the sta…