To help understand water purification, Wananchi has compiled a series of articles describing in layman’s terms the various aspects of water treatment. We hope that this will provide guidance on what machines to choose and how they will operate once in action.

The simplest and most power-efficient mobile water treatment systems are used for purifying fresh water sources.

What is Fresh Water?

A Fresh Water or Freshwater source is “any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non-salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans”. Wikipedia.

Wananchi has two main fresh water systems, Séon UV (Small Groups) and Séon UVC (Large Groups) for volume of output, with a variety of specifications available upon user requirements.

Séon purifies the water using a standard format across the range. Let’s examine each process in detail.

Stage 1 – Pre-Filtration

The first stage is all about getting the worst of the suspended matter out of the water. This is generally measured as the turbidity of the water in NTU. Wananchi systems use two widely adopted methods for turbidity reduction; Disposable mechanical cartridge filters or media-filled pressure vessels, commonly known as sand filters.

Cartridge Filters

Cartridge filters are used in our smaller, lightweight water purifiers. They provide a simple and effective method for turbidity reduction. The cartridges have a 5.0-micron pore size thus trapping a significant proportion of the suspended particles in the water.

The filters will present a pressure drop or lower water flow as they become loaded with contaminant. Once finished they are simply swapped out for new ones.

Media Filters

For larger water purifiers, we employ a pressure vessel using a media bed of zeolite. This silicate, made from volcanic ash, is proven to be completely safe for contact with drinking water.

The Zeolite traps sediment in the water down to approximately 5.0-micron in size. In the same way as filter cartridges, a pressure drop, or lower water flow will become evident as the media bed becomes loaded with contaminant.

Instead of replacing the media upon loading, we simply backwash the contaminant from the media by reversing the water flow and sending the backwash flow to waste.

Interestingly, media filters become more effective with use as they settle, and the media will last for a number of years.

Stage 2 – Activated Carbon

Séon uses activated carbon filter cartridges to further lower the particulate content and absorb Volatile Organic Compounds (VOCs) and some chemicals. The core purpose of this is to remove taint, taste, and odour. It also offers exceptional Cryptosporidium and Giardia protection. Typically, we use 0.5-micron cartridges for exceptionally small particle removal.

Carbon filters require a specific minimum contact time with water. This allows sufficient time for contaminants to be absorbed by the carbon.

Activated carbon is a time proven and very affective process for getting the job done. At this point the water is now clear and good tasting water with no noticeable odour.

Stage 3 – UVC Disinfection

Now the water quality is quite high, it is time to sterilise from harmful pathogens. To do this we use UVC light.

Water is passed through radiated germicidal UVC light which irradiates 99.99% of pathogens and bacteria. The clarity of the water after passing through the Stage 2, 0.5-micron filter ensures high effectiveness of the UVC process by preventing bacteria and pathogens from `hiding` from the UVC light on particulate matter. Essentially the UVC light needs line of sight to work. At Wananchi we call this the “dark side of the moon” affect.

The UVC light works by damaging the genetic material (DNA or RNA) in bacteria and viruses, inhibiting their ability to replicate, and causing their normal cellular functions to break down.

Wananchi water purifiers use class leading UVC emitters developed by Aquisense Technologies, world leaders and suppliers to NASA.

Stage 4 – Micro Filtration

Next, we polish the water using microfiltration, which incorporates a fine filter cartridge with a pore size of 0.1 – 0.2 microns. This process further lowers the water turbidity including trapping the irradiated pathogens from Stage 3.

With the 2-stage biological protection, clarity, good taste, colour, and lack of odour, we can pronounce the water good quality, safe drinking water. The product can be deemed equal in quality to bottled or tap water.

Stage 5 – Post Purification Disinfection

Whilst the product drinking water is of excellent quality, what happens next potentially exposes it to cross contamination undoing all the good work done.

Cross contamination can occur from a dirty tap at the end of the hose, contaminated delivery pipes, container, or tank that the water is delivered into, contaminated air settling on the water surface and even from human, animal, or insect indirect or intentional interaction with the purified water.

To minimise this risk to acceptable levels (As described by the World Health Organisation – WHO), it is normal practice to dose the product water with disinfectant or chlorine. The disinfectant kills pathogens introduced from cross contamination keeping the water safe to drink. Any municipal water supply piped to your home has residual chlorine for just this purpose.

Wananchi systems can include Automated Disinfectant Dosing (ADS) to simplify this process. Simply set the system for the chlorine strength and type used and for the residual chlorine strength in the water. (Typically, 0.5 – 5.0 ppm)

Water Pumping

Wananchi’s fresh water systems use a single pump for the water treatment process. This pump pulls the water from the source, then pressurises the water to push it through the stages of water treatment. Depending on the systems, the pressures are typically between maximums of 35 and 70 psi.

Our systems also operate using a water on demand action; open or close the tap on the end and the system will switch on and off delivering water just like your taps at home.

As the filters are clogged, the water pressure will start to drop off.

User Interaction

To keep our water purification systems simple and reliable, there is minimal user interaction. This consists of:

  • Connecting a limited number of colour coded hoses and cables
  • Connecting to a power source (if required)
  • Switching on

General maintenance involves:

  • Changing filter cartridges when flow drops
  • Re-filling dosing tank
  • Periodic sterilising of hoses
  • Period system flush with disinfectant


An that’s our first chapter introducing water purification, look out for more chapters and thanks for reading.

Speak to the Wananchi Team Today…