Newly established nonprofit organisation Water Footprint Community Development (WFCD) has designed a mobile water purification system for instal- lation in rural and remote areas that lack basic infrastructure such as electricity and potable water.
The Sawazi water purification system uses chlorine as a disinfectant, and a flocculation chemical developed in the 1980s by retired water purification expert and WFCD member Leon Buchan.
The flocculent compound removes dirt and debris by binding the dirt, which creates larger particles. These particles, weighed down by their increase in mass, settle at the bottom of the system to create sediment, thereby sepa- rating the water from the contaminants.
The chlorine sanitises the clear water that sits above the debris. However, some chlorine gets trapped in the sediment, which disinfects it, making it safe to discard into the environment, unless the sediment contains other harmful materials such as heavy metals, in which case it would need to be disposed of in an appropriate manner.
Depending on the volume of water being treated, the system can produce clear and safe drinking water in minutes – where the volume of water is larger, more time is needed for the flocculation and settling processes to take effect. On average, it has been esti- mated that 1 ℓ of water can be purified in about ten minutes.
Buchan has confirmed that the technology not only removes 99.9% of microorganisms such as bacteria, viruses and protozoa, but also has the ability to precipitate out heavy-metal pollutants.
Further, it can produce 1 000 ℓ/h of pot- able drinking water at a minimal cost of between R4 and R8. However, this only reflects the cost once the system starts operating and excludes initial investment in the Sawazi system, which includes the manufacturing of two tanks and a mixing system.
Buchan has been working on prototypes for several years, developing a hand-held model that can be used manually in any remote area, says WFCD team leader Vernon Swart.
He adds that bigger units, capable of treating up to 20 000 ℓ/h of water, have also been developed, but explains that these units are powered electrically. Smaller systems can be powered by fuel or manually powered using hand-pump technology.
Further, Swart tells Engineering News that WFCD is busy with a new cage-design model that is light enough for two people to lift and carry when empty.
The WFCD was established earlier this year under the auspices of independent consultancy Water Footprint Certification Consultancy – managed by the same team – as a social responsibility campaign.
The organisation’s aim is to improve access to potable water for rural communities in South Africa and Africa and to assist communities in improving their water footprint, which involves their water consumption and methods of disposal.
Swart says the WFCD was intended to be an awareness programme rather than a product solutions provider. He emphasises that the need for education on the dangers of using contaminated water and the imminent scarcity of water is more important than implementing the Sawazi solution.
However, the Sawazi water purification plant has enabled the organisation to initiate the education process, as well as show communities how to purify their water to make it fit for human consumption.
“Nevertheless, there are still costs involved in supplying communities with the system, and we need to remember that the communities cannot carry the cost of buying the system,” says Swart.
He explains that the WFCD is trying to manufacture the system for under R10 000 a unit, which it says will require corporate sponsorship.
“We have, therefore, been working on involving corporates in the initiative to carry the cost of producing Sawazi water purification units,” he adds.
In the next year, the WFCD plans to launch a campaign aimed at collaborating with bigger companies and multinationals to spread awareness on sustainability in general.
It plans to incorporate carbon awareness in the campaign, bringing solar power technology, as well as the WFCD’s water purification technology to communities, says Swart.
“We want this drive to be focused on sustainability in rural and remote areas, as well as in township areas.”
Swart tells Engineering News that the campaign will be launched as soon as the WFCD settles negotiations with prospective partners.
When Buchan developed the flocculent used in the Sawazi purification system, South Africa was enjoying low-cost good-quality drinking water and water pollution was not as bad as it is at present.
The product did, however, take off overseas when it was first developed, and it is still being used by the US military and is registered with the US Environmental Protection Agency.
Swart believes the state of South Africa’s water resources has reached a point where the country will benefit from the flocculent. This is why, in April this year, the WFCD decided to design the Sawazi, a mobile system that can be installed with ease, overcoming the shortcomings of traditional small-scale water purification plants by eliminating complicated controls and procedures, says Swart.
The plant is also easy to use as no knowledge of chemical dosing, pH levels or flocculation processes is required to operate a Sawazi plant, he adds.
Source Article from http://www.engineeringnews.co.za/article/npo-develops-mobile-purification-system-educates-rural-communities-2012-10-12
NPO develops mobile purification system, educates rural communities
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