The future of real-time purification for developing countries

Solving the global water contamination crisis

The Water Crisis

When I was looking at this problem, I broke it down into two main aspects: water access and water cleanliness.

The Water Contamination Crisis

19% of the Ugandan population relies on unimproved or surface water for their daily needs. This means that over 8 million people are drinking from sources like streams, ponds, unprotected hand-dug wells, and more.

An E Coli breakout in Uganda that killed thousands of people
  1. Anthropogenic activities (mining and smelting operations, industrial production and use, and domestic and agricultural use of metals)
  2. Open defecation

TL;DR:

  • Heavy metal contaminants come from anthropogenic activities. For example, acid rain will break down soils and release heavy metals into the water. (Acid rain is usually experienced in the month of August after the mid-year dry season in Uganda.)
  • E Coli is found in animal feces (mainly cattle) and animals in Uganda are defecating in the open which is contaminating water sources.
  • Cholera is passed along through water sources that are contaminated with the feces of an infected person. Over 3 million people in rural Uganda practice open defecation.
  • Typhoid is commonly passed through using toilets that have contaminated feces and touching your face/mouth before thoroughly washing your hands. This means drinking water from water sources contaminated with infected feces (Over 3 million people in rural Uganda practice open defecation) .will expose people to Typhoid.

Existing Solutions

After having a clear, validated breakdown for the water contaminates I wanted to look into existing solutions to understand how people were currently cleaning the water.

Boiling

About 60% of people in Uganda will boil their drinking water. To boil the water, the communities will collect and burn firewood under the water.

Solar Disinfection

The second method I found that people use to disinfect water is called solar disinfection. In developing countries, roughly 5 million people use it daily.

Biosand Filters

On average a single biofilter filter costs a total of $70USD to construct and install for about 10–15 people.

Diffrent types if Biosand filters

The future of real-time purification

These methods are generally applicable to any developing countries around the world. Looking at the weather conditions, way of life, etc. at any specific country could tell you whether this solution would be effective.

  1. Cost — people living in developing countries don’t have hundreds of dollars sitting around.
  2. Sustainability — I wanted to ensure that the water source wasn't something that constantly had to be replaced because that’s a huge inconvenience.
  3. What the system filtered out — if the method I was exploring didn’t filter out everything in the water the implementation wouldn’t have been very useful.

Dewgood — Harvesting Water From Air

When water vapour in the air comes into contact with something cold its molecules slow down and get closer together. When that happens, the water vapour turns into liquid water droplets. The DG-10 is the Dewgood product that is able to speed up that process by using electricity.

Zero mass water — Creating Drinking Water by Combining Sunlight and Air

Zero mass water is a company with a product called SOURCE which is a solar-powered and infrastructure-free drinking water solution.

What the product looks like
  1. Solar energy powers the panel completely off-grid.
  2. Fans draw in ambient air and push it through a hygroscopic (a water-absorbing material) that traps water vapour from the air.
  3. The water vapour is extracted and passively condenses into a liquid that is collected in the reservoir.
  4. Minerals are added to the water to make it distilled.

Gravity Water — Using Rain Water

Rainwater isn’t commonly at risk of pollutants until it reaches the ground where contamination occurs and WHO considers rain as an “Improved Drinking Water Source”. Gravity Water is leveraging this to provide people access to clean drinking water.

Rainwater harvesting set up for one of Gravity Water’s systems at a public school in Kathmandu, Nepal

Limitations

The biggest limitation I see here is the dependence on it raining. The vast majority of people who don’t have access to safe drinking water around the world live in the Tropics and Sub-tropics and in many tropical and subtropical regions, rainfall varies much more than temperature does so it’s fairly unpredictable. But other than that it’s a very promising solution.

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improving the global quality of life | nylapirani.com

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