Development of a novel off-grid drinking water production system integrating electrochemically activated solutions and ultrafiltration membranes

Abstract

10Approximately 800 million people live without clean drinking water. Diarrhoea is responsible 11 for between 1.7 and 2 million deaths each year (primarily children) which are the result of 12 poor drinking water quality and sanitation. The main aim of this study was to demonstrate 13 the production of drinking water from a raw water source using an off-grid drinking water 14 production system. The off-grid drinking water production system (DWPS) developed at 15 UWE Bristol, combines an ultra-filtration (UF) system with in situ generation of 16 electrochemically activated solutions (ECAS). ECAS has two functional roles within the 17 system; to manage biofilms within the UF system and as a disinfectant. Integrated in-situ 18 probes (pH, oxidation reduction potential, chlorine, conductivity and dissolved oxygen) 19 coupled with a water quality sensing network (pH, water temperature, conductivity and 20 dissolved oxygen) enabled real time monitoring of; the operational efficiency of the DWPS, 21 and the physicochemical parameters of both the raw water source and the produced drinking 22water. Spot samples of both raw and treated water were sent for independent chemical and 23 microbial analysis at an accredited laboratory which demonstrated that the DWPS produced 24 biologically safe potable drinking water according to the Drinking Water Inspectorate (DWI) 25 standards. Samples from the raw water source were shown to be consistently unsuitable for 26 human consumption, failing several of the DWI standards for potable water supply, including 27 coliform bacteria. This study demonstrated that the novel off-grid DWPS was capable of 28 producing DWI standard drinking water from a heavily biologically contaminated water 29 source. 30 Keywords 31Off-grid; drinking water production; electrochemically activated solutions; ultrafiltration. 32

Development of a Community-scale Autonomous Water Purifier (AWP) Prototype to Remove Heavy Metals

“…Parame ters SODIS (Vivar et al, 2017) ECAS (Clayton et al, 2019) AWP However, many of these microorganisms have a mechanism capable of repairing these effects. For this reason, the SODIS method can only eliminate 97.5% of E. coli and coliforms bacteria.…”

“…Other researchers reported hybrid systems using solar radiation, these systems were pilot-scale solar photoreactors, which included flat plate reactors (FPRs) and compound parabolic collector (CPC) reactors (Ochoa-Gutiérrez et al, 2018;Wang et al, 2016). Many hybrid systems for remote locations have been developed to desalinate water through reverse osmosis (Alghoul et al, 2016;Peng et al, 2018) and ultrafiltration membranes (Clayton et al, 2019).…”

Long-term trial of a community-scale decentralized point-of-use drinking water treatment system

“…There is a current technology gap for decentralised treatment options at a community scale. Hence, research and development of off-grid or decentralised water treatment systems for the provision of safe drinking water has increased in recent years [14][15][16][17][18]. These systems represent alternatives to centralised water treatment, which are often unfeasible in remote, rural or temporary community locations [14][15][16][17]19].…”

“…Filtration techniques physically remove particulates through size exclusion to help reduce water turbidity, reduce concentrations of organic matter, and reduce microbial load, thus reducing the presence of potentially pathogenic microorganisms [17]. However, filtration alone does not provide biologically safe water for consumption [18]. Minimising organic matter prior to disinfection processes through filtration will increase disinfection capability, as well as reduce the potential formation of unwanted disinfection by-products [DBPs] [22].…”

“…This study builds upon a feasibility investigation of a small-scale proof-of-concept decentralised drinking water production system (POC-DWPS) previously developed that combines multi-step filtration and disinfection processes [18]. The system described previously has been scaled up, improved and manufactured to enable an increase in the volume of treated water produced, from 0.12 m 3 hr -1 to a maximum output of 0.75 m 3 hr -1 .…”