Exploring electrochemical disinfection for decentralized drinking water production

Exploring electrochemical disinfection for decentralized drinking water production: from Laboratory Research to Field Application in Ghana

Nanni, Carolina (TU Delft Civil Engineering & Geosciences)

van Halem, D. (mentor)
Vermaas, D.A. (graduation committee)
Rijsdijk, S. (mentor)
Trikannad, S.A. (mentor)

Delft University of Technology

Civil Engineering | Environmental Engineering

2024-06-20

Decentralized drinking water production continues to face challenges in achieving acceptable standards for human consumption. This is mainly due to difficulty in developing treatments that can operate effectively in low-resource settings, either due to complications associated with providing the system in a decentralized context or overall unsatisfactory performance of the technology adopted. Electrochemical systems are emerging technologies within decentralized settings which provide many advantages to being adapted in resource-limited areas. This study focuses on understanding the mechanisms behind the electrochemical
disinfection for the treatment of surface water. Laboratory experiments were conducted to evaluate the performance of an RuO2/IrO2 and a Magneli-phase reactor for the disinfection of a bacteria species, Escherichia Coli, and a virus species, ΦX174. The two reactors are characterised in terms of distinct anodic properties and their performance is assessed by promoting different electrochemical reactions for the generation of various disinfectant agents within the electrochemical cell, with specific focus on the formation of chlorine and Reactive
Oxygen Species (ROS). Chlorine-based disinfection proved to be the primary agent in the removal of both pathogens; a 4 log removal for E. Coli was achieved at an energy use of 0.41 kWh/m3 for RuO2/IrO2 and of 0.31 kWh/m3 forMagneli, and a 5 log removal for ΦX174 was achieved at 2.88 kWh/m3 for RuO2/IrO2 and for 1.18 kWh/m3 for Magneli.
To further assess the viability for the treatment of surface waters in decentralized settings, the RuO2/IrO2 was also tested in a field setting in Ghana making use of different water types to compare the utility in using an electrochemical reactor to produce chlorine for disinfection as compared to traditional disinfection methods.  Seawater, lagoon and river water were tested, achieving an energy use per gram of produced chlorine of 0.007, 0.046 and 0.066 kWh/gchlorine for a produced chlorine dose of 35 mg/L for seawater and 5 mg/L for the lagoon and river water. With these results, chlorine can be produced from river water at an equivalent dosage to traditional chlorine tablets, and at a cost that is 40 times lower.

http://resolver.tudelft.nl/uuid:b6f54473-e045-40a4-9e22-342974739656

Student theses

master thesis

© 2024 Carolina Nanni