Integrated membrane and microbial fuel cell technologies for enabling energy-efficient effluent Re-use in power plants

Abstract

Municipal wastewater is an attractive alternative to freshwater sources to meet the cooling water needs of thermal power plants. Here we offer an energy-efficient integrated microbial fuel cell (MFC)/ultrafiltration (UF) process to purify primary clarifier effluent from a municipal wastewater treatment plant for use as cooling water. The microbial fuel cell was shown to significantly reduce chemical oxygen demand (COD) in the primary settled wastewater effluent upstream of the UF module, while eliminating the energy demand required to deliver dissolved oxygen in conventional aerobic treatment. We investigated surface modification of the UF membranes to control fouling. Two promising hydrophilic monomers were identified in a high-throughput search: zwitterion (2-(Methacryloyloxy)-ethyl-dimethyl-(3-sulfopropyl ammoniumhydroxide, abbreviated BET SO), and amine (2-(Methacryloyloxy) ethyl trimethylammonium chloride, abbreviated N(CH)). Monomers were grafted using UV-induced polymerization on commercial poly (ether sulfone) membranes. Filtration of MFC effluent by membranes modified with BET SO and N(CH) exhibited a lower rate of resistance increase and lower energy consumption than the commercially available membrane. The MFC/UF process produced high quality cooling water that meets the Electrical Power Research Institute (EPRI) recommendations for COD, a suite of metals (Fe, Al, Cu, Zn, Si, Mn, S, Ca and Mg), and offered extremely low corrosion rates (<0.05 mm/yr). A series of AC and DC diagnostic tests were used to evaluate the MFC performance.

Graphene-Infused Hybrid Biobattery–Supercapacitor Powered by Wastewater for Sustainable Energy Innovation

“…Our previous investigations utilizing a comparable biobattery device, designed similar to a two-compartment MFC, already demonstrated COD removal rates ranging from 75% to 94% using the same municipal wastewater [40] employed in the present study. Building upon these findings, it is evident that hybrid biobattery devices hold potential for harnessing and storing energy that can be utilized for enhancing the sustainability of secondary and tertiary treatment processes.…”

Oxygen Reduction Reaction with Manganese Oxide Nanospheres in Microbial Fuel Cells

“…GF, RVC, carbon cloth (CC), and carbon paper (CP) electrodes were coated with the ink to obtain ORR cathodes for the MFC studies. These electrodes were cleaned with acetone and ammonium peroxydisulfate and heated at 450 °C for 30 min. , The pretreated electrodes were washed with distilled water thrice and immersed in the ink. The mass of the ink was adjusted to be ∼5% of the equivalent mass of the electrode.…”

A Novel Computational Platform for Steady-State and Dynamic Simulation of Dual-Chambered Microbial Fuel Cell

“…5,7,9 The performance of a MFC depends upon a wide range of parameters that includes electrode materials, reactor volume, membrane thickness, membrane conductivity, membrane-active area, operating conditions, reactor design, distance between anode and cathode, fuel feed flow rate, bacterial yield and decay rate, influent concentrations and substrate nature, among many others. [10][11][12][13][14] In addition to all these parameters; the complexity of MFC design, as well as high cost of materials and membranes, are also some prominent hurdles in MFC's industrial applications. 15,16 In order to pave the path of applications in industries, there are two approaches of MFC optimization: (i) experimental optimization and (ii) mathematical modeling.…”