TITLE:
Disinfecting Water with the Carbon Fiber-Based Flow-Through Electrode System (FES): Towards Axial Dispersion and Velocity Profile
AUTHORS:
Djamel Ghernaout, Noureddine Elboughdiri, Saad Ghareba, Alsamani Salih
KEYWORDS:
Carbon Fiber Felt (CFF), Electrodisinfection, Gram-Negative Bacteria, Gram-Positive Bacteria, Axial Dispersion, Velocity Profile
JOURNAL NAME:
Open Access Library Journal,
Vol.7 No.4,
April
8,
2020
ABSTRACT: Electrochemical technology for the killing of pathogens has been largely investigated. Lately, Ni et al. [1] published excellent research on the disinfection efficiency of a carbon fiber-based flow-through electrode system (FES) versus Gram-negative bacteria (Escherichia coli and fecal coliform) and Gram-positive bacteria (Enterococcus faecalis and Bacillus subtilis) in normal saline over a large span of applied voltages (1 - 5 V) and hydraulic retention times (HRTs) (1 - 10 s). They established that the Gram-negative microbes were more susceptible to FES for their thinner cell walls and over 6.5 log reduction (no live bacteria found) was obtained at the applied voltage of 2 V and HRT of 2 s; however, Gram-positive microbes were demobilized at slightly bigger voltages (3 V, 2 s) or longer HRTs (2 V, 5 s). Demobilizing microorganisms was related to the alteration and laceration of cell membranes mostly via anode direct oxidation in the absence of bacterial regrowth. Further, the disregarding formation of the free chlorine at low voltages (≤2 V) could avert the production of possible chlorinated disinfection by-products. Therefore, FES could furnish an undeveloped substitute to traditional disinfection processes for eliminating pathogens in water. This work concludes that focusing on axial dispersion and velocity profile inside anode will be very useful in comprehending the transport phenomena and proposing a fresh model that merges the axial dispersion and velocity profile for the FES. Such a research trend will more encourage the FES implementation at the large industrial level for disinfecting water.