The tap water you drink may not be as purified as you may think, as it has been found sometimes to carry health-threatening dissolved organic contaminants that have managed to pass through the multiple stages of wastewater treatment.
According to the World Health Organisation, contaminated water is the cause of more than 400 000 diarrhoea-related deaths in the world every year. The organisation also found that such dirty water may also spread cholera, polio and dysentery.
The department of water and sanitation released South Africa’s last Blue Drop report in 2017. This water quality report showed that only a fraction of municipal drinking water systems complied with the Blue Drop standards.
Water specialist Anthony Turton said everyone in South Africa lives downstream from a sewage discharge point that flows into their drinking water supply, which is why the Blue and Green Drop reports are so important. “In effect then, South Africa recycles wastewater for drinking purposes.”
But Farai Dziike has tried to find a solution by creating a purification module at his company, Indoni Yamanzi Hydrotech Solutions SA.
Dziike’s free-standing unit, eight years in the making, serves as an add-on scalable modular unit for conventional wastewater treatment plants.
This technology will serve as the last stage in wastewater treatment and aims to purify the dissolved organic contaminants that may cause water to have bad colour, bad taste and a bad smell.
As many wastewater treatment plants do not produce potable water, this novel technology is also expected to assist the country during drought by recycling more water for human use and agriculture.
Unlike existing plants, which rely primarily on electricity for their functioning, Indoni Yamanzi Hydrotech Solutions will only use solar energy to treat and purify water.
Dziike, the founder of the green off-grid technology, said this technology enables passive treatment of wastewater through a sunlight-activated catalyst, and a complete organic contaminant degradation with no effluent discharge.
This means that no harmful substances can pass through the Indoni Yamanzi stage, making it safer to drink. “Water containing dissolved organic contaminants passes through a mounted fixed bed nanophotocalyst reactor, through which organic contaminants are photo-electrocatalycally degraded to give pure quality potable water,” said Dziike.
While the main reason for this invention was to save people from water-borne diseases, Dziike said he also wanted to ensure there were other sources of potable water by recycling both grey and black wastewater, instead of the country mainly depending on the Lesotho Highlands Water Project for the supply of water.
“There’s a genuine need for providing a solution to the lack of access to potable water in the face of recurring droughts and unsustainable methods of water treatment that result in some municipalities offering a poor service delivery,” he said.
Indoni Yamanzi Hydrotech Solutions SA has also been selected in the top 10 for the Global Cleantech Innovation Programme. “It’s exciting, after eight years of working on the project. But what matters more is for this to help supply clean drinking water to the people.
“Recycling water is important for both cities and rural areas — especially rural areas — because [this] water usually has a bad taste. Sources are usually boreholes. If we can clean this water, we ensure safety for livestock and humans living there.”