Purifying unsafe water

What is a DSP?
It is an alternative source of viable drinkable water in areas of water shortage or where only sea water is available.

Who is Samuel O Otukol?
I am a Ugandan living in Canada. I was born in Butebo, Pallisa District. My parents are Manjeri Naula and Erenesti Okirya. I studied at Bukedi College Kachonga, Busoga College, Mwiri and studied forestry at Makerere University. I came to Canada in 1975 to do a Masters Degree in Forestry at the University of New Brunswick and then a PhD at the University of Toronto. I work for the government of British Columbia, Canada. I have five children.

How is your innovation relevant to Uganda, a country with no ocean water?
The methodology works with any contaminated water which does not have solid particles suspended in the water. Some realities in Uganda have not changed much. The northern and eastern parts of the country are still quite dry. I know there are more boreholes now, but some of them are tapping into brackish water which could be harmful to health. Some streams are still heavily sedimented, and this solution could be helpful. Anything that would improve use of salt water is a definite benefit.

How is the DSP unique and feasible from the rest of the current technologies?
The process is unique in that it occurs at modest temperature. The proposed process can also use solar energy in remote areas. It uses cheap materials to achieve evaporation. It is simpler technology to use in Third World countries. It separates salts from fresh water and is not a form of filtration.

What is the anticipated positive change it will cause?
It will allow places that have salty or contaminated water to use it. It could lead to increased agriculture in places where water is a limiting factor. It allows the collection of sea salts, which would be an asset in African countries with poor soils because the salts can be used to create organic fertilisers. It improves water shortages in drought-stricken areas, or where existing desalination methods have proved ineffective.

Is DSP something one can own in their house or a community thing the way you would see a community water pump or spring well?
The technology can be scaled down to supply a family or scaled up to produce water for a small community. We anticipate being able to scale up to produce water for a small community.

When did you start this innovation?
I started working on this around 2000 as a hobby. But I eventually filed for patent in the US and Canada and took about five years to finalise.

What was the inspiration for your project?
Partly it was because I used to walk long distances to fetch water when I was growing up in Uganda. During droughts in my home area, we walked up to three kilometers when local streams dried up. Things seemed to be pretty desperate. But coming to Canada and seeing so much ocean water motivated me to try tinkering with it.

What process did you go through to have this done?
I started by developing a theory that ceramic material might help in increasing salt water surface area for evaporation. I did a pottery course to get familiar with properties of ceramics. For instance, after moulding clay, if you begin firing it, five to 10 per cent of the volume of the ceramic is air space that allows water to flow through it freely. If you can imagine a pot with water inside it, the water eventually works its way to outer surface of the pot and once it is outside, it evaporates. The evaporation on the surface cools the water inside.
What were the challenges and how did you overcome them?
The biggest challenge was performing experiments without a decent laboratory. The tests were related to checking how effective change to the different factors such as airflow, temperature and surface area were on increasing evaporation and what kind of cooling was necessary to create condensation. Evaporation is easy to achieve, but creating condensation is quite tricky and requires good knowledge of refrigeration technology. A partner found a person with refrigeration knowledge, but working with other people you do not know well has its risks. They can turn around and steal your idea. The other hard moments were in trying to find funding to move forward. I used my own money which can be a stretch.

What is the cost of a single DSP?
For materials bought at retail price, the total cost is Canadian $2000 (Shs4.7 million).
With mass production, construction cost for a small machine will add up to Canadian $400 (Shs951, 200). These are rough estimates though.

Why do you think you made it to the final list?
My technology proposes a solution to one of Africa’s problems. Africa is in dire need of fresh water. Uganda is lucky, but with this innovation, countries like Namibia, Botswana, Kenya, Somalia, Egypt, Libya, Morocco, Mauritania, Mali, and many others could see some relief.

You have not won yet, but at least listed; what does it mean to you?
It means I can move forward quite quickly. It also provides me with an expanded network of people who can help. What I want to see next is more use of the ocean water for fresh water.

About the Water Distillation System and Process (DSP)

How it works.

DSP works by accentuating the factors that influence water evaporation such as exposed water surface area, heat, air motion and amount of sunlight. So salt water is injected into a chamber where those factors are manipulated, for example increasing temperatures and, or the rate of air motion and evaporation happens. Salty water is evaporated at low temperatures (30 to 50 degrees Celsius) and then condensed into fresh water. The evaporated vapour is then extracted and condensed back to liquid. When evaporation happens, salts are separated from the fresh water. The vapour is almost pure water – almost because the moving vapor may pick up materials from the collusion with machine walls and tubing.

Capacity.

The chamber can be altered to configure the components in different ways. It is not intended to hold water. It is a transit place for transforming liquid water to vapour. It is a continuous flow of water. It can generate up to 10 gallons (each gallon contains about 4.5 litres) of fresh water per day. The yield depends on the capacity of the cooling coil to transform the vapour to liquid.

Why DSP.

The process is unique in that it occurs at modest temperature. The proposed process can also use solar energy in remote areas. It uses cheap materials to achieve evaporation. It is simpler technology to use in Third World countries. It separates salts from fresh water and is not a form of filtration.

Materials for DSP.

Refrigerant compressor, a condenser, a cooling coil, a salt water source container, a means to expand salt water surface area, a means to move air, tubing to circulate refrigerant, tubing to move alt water from one place to another, a fresh water collector container, ventilation to allow good air circulation, controls for the electrical system, wiring for the electrical system.