Technologies

Pulsed Electric Field for Drinking Water Disinfection


Abstract/Technology Overview

Microbiological infestation is a known cause of water pollution in drinking water sources. Common waterborne pathogens include Pseudomonas, Aeromonas, Mycobacterium and Legionella bacteria. There have been a number of cases of Legionella bacteria being detected in new buildings in Hong Kong.

Water disinfection technologies such as chlorination, ozonation, heating and reverse osmosis are now widely used in drinking water disinfection. However, a high concentration of chlorine produces a pungent smell and unwanted toxic by-products. On the other hand, heating and reverse osmosis can be energy consuming and expensive.


Technology Features, Specifications and Advantages

The invention provides a safe, effective and environmentally benign device for point-of-use (POU) disinfection of tap water for drinking by subjecting microorganisms in the water to an intense, pulsating electric field generated between micro-engineered electrodes. The intensity, polarity, strength, duration and the interval of the pulse are selected to render the microorganisms non-viable by causing irreversible damage through a combination of cell wall collapse, osmotic stress and enhanced penetration of residual disinfectant. In this way, the water is disinfected without the excessive use of chemical disinfectants and biocides that can alter the taste and quality of the water and potentially lead to resistance and tolerance in the microorganisms. The device is applicable not only in domestic situations but also to the public, commercial and industrial premises where safe drinking water is paramount.

 


Potential Applications

The new pulsed electric field disinfection technology can kill bacteria by damaging their cell walls so they are no longer infective. Current technology uses a high-input voltage to generate a pulsed electric field, which uses up to a hundred thousand volts and creates a potential electrical hazard for operators. The device is designed to use a low-input voltage. This portable battery-powered device can be installed on any domestic or public tap water systems. It is cost-effective, environmentally friendly and safe for disinfecting tap water at the point of use. This device can be used for drinking water disinfection can be used in households, restaurants and washrooms, etc.


OVERVIEW
Contact Person

Samuel Wong

Organisation

The Hong Kong University of Science and Technology

Technology Category
  • Sanitisation
Technology Status
  • Available for Licensing
Technology Readiness Level
  • TRL 4
Keywords

Pulsed Electric Field, Water Disinfection