Electrocoagulation as a Pretreatment for Electroxidation of E. coli

Abstract

Insufficient funding and operator training, logistics of chemical transport, and variable source water quality can pose challenges for small drinking water treatment systems. Portable, robust electrochemical processes may offer a strategy to address these challenges. In this study, electrocoagulation (EC) and electrooxidation (EO) were investigated using two model surface waters and two model groundwaters to determine the efficacy of sequential EC-EO for mitigating Escherichia coli. EO alone (1.67 mA/cm2, 1 min) provided 0.03 to 3.9 logs mitigation in the four model waters. EC alone (10 mA/cm2, 5 min) achieved ≥1 log E. coli mitigation in all model waters. Sequential EC-EO did not achieve greater mitigation than EC alone. To enhance removal of natural organic matter, the initial pH was decreased. Lower initial pH (pH 5–6) improved E. coli mitigation during both stages of EC-EO. EC-EO also had slightly greater E. coli mitigation than EC alone at lower pH. However, EO alone provided more energy efficient E. coli mitigation than either EC or EC-EO.

River water treatment by continuous electrocoagulation: insights into removal of acetaminophen, and natural organic matter

“…A substantial difference in NOM removal could be observed when the HRT was .20 min, along with COD indicate the recalcitrant nature of organic pollutants present in river water. Similar results of NOM removal (∼60%) from surface water using EC with steel electrodes have been reported earlier (Lynn et al 2019). These authors noted that a higher concentration of NOM in surface water also results in higher removal of NOM with EC.…”

“…Several technologies have been researched for effective water treatment and it might be long before many of these can be considered fully ready for implementation in the field. However, one process that can be used for potable water treatment is electrocoagulation (EC) as it offers multiple advantages such as ease of implementation, smaller footprint, and non-selective removal of pollutants, low operating cost, lower chemical consumption, easy operation, short operating times, cost-effectiveness, and minimal sludge generation (Garcia-Segura et al 2017;Lynn et al 2019). EC can be considered as an alternate treatment over conventional chemical coagulation for drinking water treatment.…”

Direct Potable Reuse: The Singapore NEWater Project as a Role Model

“…Electrochemistry is more and more viewed as a central knowledge for expanding a possible society from fuel cells to waste electrochemical oxidation, desalination, and water reuse [42] [43] [44]. Electrochemical AOPs are magnetizing many of the awareness, thanks to their numerous benefits, comprising employing a more hygienic reagent (electricity), potential to attain outstanding levels of mineralization, versatility, elevated energy effectiveness [45], amenability of automation and safety [46] [47] [48] [49]. As shown in Table 1, electro-Fenton is fast rising as the most encouraging between electrochemical techniques [50] [51], particularly via the integration with nanomaterials like graphene [52] [53] or boron-doped diamond (BDD) to boost anodic oxidation as an extra source of • OH [3] [54].…”

Effect of pH on Escherichia coli Removal by Electrocoagulation and Elimination Kinetics after Treatment

“…Several disinfection technologies, such as ozonation, ultraviolet disinfection, and chlorination, are currently in use for water treatment. However, even though these technologies are effective, their utilization is limited by operational safety, the formation of unwanted by-products, and a high cost for operation and maintenance [1][2][3][4].…”

“…One of the emerging technologies that proved its efficiency against a broad spectrum of microorganisms is electrochemical disinfection. It has gained increasing attention as an alternative to the conventional methods of disinfection since it is environmentally friendly and is known to inactivate a wide variety of microorganisms, from bacteria to viruses and algae [3][4][5][6][7][8][9][10].…”