High hopes for next-gen desal
Australian researchers have unveiled a new, solar-powered water-purifying device that could deliver clean water to remote communities worldwide.
Researchers at Monash University have developed a solar steam generation system that achieves efficient and continuous clean water production from salty water with almost 100 per cent salt removal.
Through precisely controlling salt crystallisation, the device also can harvest the salts.
The design has been tested on seawater from Lacepede Bay in South Australia, and findings published in the international journal Energy & Environmental Science.
Researchers created a disc using super-hydrophilic filter paper with a layer of carbon nanotubes for light absorption.
A cotton thread, with a 1mm diameter, acted as the water transport channel, pumping saline water to the evaporation disc.
The saline water is carried up by the cotton thread from the bulk solution to the centre of the evaporation disc. The filter paper traps the pure water and pushes the remaining salt to the edges of the disc.
The light absorbance was measured to 94 per cent across the entire solar spectrum.
The disc also exhibited a rapid temperature increase when exposed to light in both dry and wet states, rising from 25℃ to 50℃ and 17.5℃ to 30℃ respectively within one minute.
This technology has also great potential in other fields, such as industry wastewater zero liquid discharge, sludge dewatering, mining tailings management and resource recovery.
An estimated 844 million people do not have access to clean water, while every minute a newborn dies from infection caused by lack of safe water and an unclean environment.