RSE
A A
Login
login name
password
login
GSE
ITA english

Report RSE 18002368

Microbial fuel cells and other electrochemical systems: results of the activity

Report

2017

Request Document (12.07 MB, .pdf)

P. Cristiani (RSE SpA)

CONVENERGIA 2017 - Small scale energy conversion plants

The activity aims to develop an innovative technology based on microbial fuel cells as bio-technological tools that could contribute to remove the organic load from the effluents. The innovative bioelectrochemical process, the bio-energy production, the study of the materials and the cell geometries are the aspects mainly considered, in relation to the experiments conducted.Simplified and cost-effective prototypes of microbial fuel cells were built and tested for experimental, educational and demonstrative purposes.

The activity aims to develop an innovative technology based on microbial fuel cells (electrochemicalprocesses mediated by bacteria) as bio-technological tools that could contribute to improve theefficiency of electricity in the industrial and municipal services sectors, with particular reference to civiland industrial wastewater treatment plants. The removal of the organic load from the effluents with theinnovative bioelectrochemical process, the bio-energy production, the study of the materials and the cellgeometries are the aspects mainly considered, in relation to the experiments conducted.

Simplified and cost-effective prototypes of microbial fuel cells were built and tested in the Milan-Nosedo wastewater treatment plant and in other plants in the surrounding of Milano, at Bresso(Consorzio acque potabili CAP) and at Carimate (Sud Seveso Servizi SpA). In parallel, laboratory testshave been carried out on the materials and bioenergy degradation processes of different organicmatrices, in collaboration of other research institutions (mainly Università degli Studi di Milano,Dipartimento di Chimica, and CNR, Istituto di Chimica Biomolecolare at Pozzuoli) aimed at optimizingthe efficiency of the process and at exploring the potential of the bioeletrochemical technique for energyand environmental application and beyond.

Laboratory experimentation of nanoceria doped cathodes allowed to reach a cell performance increaseof an order of magnitude, exceeding the prefixed target of 1 Wm2 referred to the geometric dimensionsof the cathode.

The main results of the experimentation carried out in the purification tanks of the Milan-Nosedo plantconfirm, as a first approximation, the reproducibility of the performances of the microbial cellsexperimented in the laboratory.

Some prototypes of floating microbial cells have been tested as potential self-powered remote sensors ofthe degradation process underway in wastewater and other water quality parameters. Given the very lowconcentration of dissolved organic substances in the wastewater treated in the purification tanks (~ 20mg/L COD), the electrical productivity of these batteries has been correlated to an organic content in therange between 3-100 mg/L (COD dissolved) and to the size of the electrodes (5 – 500 cm2).

It is necessary to point out that the electrical productivity of the tested systems has not yet reached aprecompetitive industrial attraction, despite being of high scientific interest. Therefore, it is premature toattempt a comparison of the electrical performances of the tested microbial fuel cell systems and theenergy needs of the plant. Nevertheless, the experimentation carried out on the materials and theirfunctionalization with specific catalysts supporting the action of bacteria (for example nanoceria),indicates that the potential of microbial bioelectrochemical systems from the point of view ofwastewater purification can become competitive with respect to the traditional techniques. In particular,the bioelectrochemical systems developed provide new insight on advanced treatment targetted toemerging micro-pollutants in the water, as well as promise energy savings for the entire biodegradationprocess. The processes that mostly affect the energy requirements of the treatment plants have beenhighlighted, indicating a potential for reducing the energy request with the proposed electrochemicalbiodegradation, alternative to the inflow of oxygen.

In reference to other bio-energetic processes, the potential of bioelectrochemical technologies for thebiogas sector and the possibility of electrostimulate the metabolism of Thermotoga neapolitana with theaim of producing lactic acid from CO2 and acetate was also investigate.

Related Links