How it all started
I get asked if I am an engineer, industrial designer or scientist and when I answer that I studied economics people get a bit surprised. Even though I studied nothing related to technology, health or science I was always motivated to research ideas and simple technologies that could make an impact.
I studied economics because I wanted to understand how society could be better off. I learned that technology and innovation can drive development. Thru education, research and innovation, a person, a company or a country could be better off.
What if the technology that can improve people’s lives would be shared and open, what if technology itself could be improved collectively? would it produce a continuous and exponential improvement of people’s lives? I think that open source technology, open-source knowledge, research and social innovation can generate an open evolution to help improve people’s lives.
The Open Maker Movement
I had been thinking about having a space to develop creative projects. I moved to Barcelona and was inspired by all things creative happening in the city. My work was not related to open source and making at that time, but when I had more time in the last couple of years I started to find out more about the maker movement, open-source hardware, fabrication, collaboration, crowdsourcing and crowdfunding. I travelled to San Francisco a couple of times and stayed a month to learn more about collaborative projects, hackerspaces, open technology and design. Visiting Stanford´s D-school, seeing their product design examples of extremely low affordability innovations and attending the Maker Faire in San Mateo inspired me.
I went back home to Peru for a few months and started learning about the physical properties of carbon since I wanted to make a $1 DIY conductive ink that could be used with Arduino based boards to draw electric circuits for my nephews. My dad, who is very knowledgeable about mechanics and chemistry, suggested that conductive ink was probably based on carbon particles, so I learned about activated carbon and made the first conductive ink out of the charcoal remains from our fireplace.
Is the Amazon Rainforest as pristine as one imagines?
In a completely unrelated event, I travelled to the Amazon rainforest to visit friends who run reforestation projects. You would think that being in the rainforest, in such a pristine environment, full of tropical life and nature, the water in the rivers and small creeks would be very clean, at least without any human contamination. However, even in remote places like the rainforest, the effects of civilization have already caused a big negative impact. Mercury pollution from gold mining in rivers, streams and even fish is a large problem, as well as coliform bacteria coming from sewage in human settlements that are built in the middle of the rainforest. This struck me.
I realized that no matter where you are in the planet, we all will be suffering from more contamination from human and industrial activities in rivers, lakes and natural water reserves no matter where you are.
I was carrying with me a pump with a water filter based on ceramic and activated carbon. I learned that activated carbon absorbed many chemicals, while ceramics retained many particles and even some pathogens. However, the size and the cost of these filter systems were not ideal for poor countries. Doing some more research online I started learning about different technologies used for municipal water purification plants and also other portable filtering systems.
DIY filters and the latest technology
I learned that there are some filtering media that have different benefits and also have some disadvantages due to the nature of the materials used, pore size, cost, maintenance, convenience, affordability, fabrication, etc.
The most basic water filter you can build yourself for emergencies can be made using stones, gravel, fine sand and a piece of cloth or paper towel. The larger sized elements trap larger objects like other stones, dust, leaves, insects, etc., while fine sand can trap smaller particles, reducing the turbidity of dirty water. There are biosand filters using these elements, where some bacteria growing on a top layer of sand eat harming bacteria that are living in dirty water.
Another low tech method of filtering water is using ceramic filters, they can be rudimentary and self-made just like the Roman pots, using a mix of sawdust that is then burnt in the cooking process of the ceramic and leaves small pores in the ceramic walls. There is a great NGO (Potters for Peace) promoting low-cost ceramic filters impregnated with colloidal silver to kill bacteria. Ceramic filters can be also industrially manufactured with specific pore sizes, some even very small that can trap some bacteria.
Then there is also activated carbon, which is a normal vegetable (burnt coconut shells for instance) or mineral charcoal that is steamed at very high temperatures, evaporating some particles like tar, and opening up the pores in the structure. Chemical elements and compounds that can be harmful like mercury, chlorine, fluoride, lead, sodium, arsenic, lithium and pesticides can be absorbed by activated carbon.
DIY activated carbon filter in a bottle
Finally, there are membranes produced using different materials and these membranes can have really small pore sizes that can even filter salt out of seawater, and of course any other element larger than salts like protozoa, cysts, bacteria and viruses.
So at least in theory yes it was possible to filter dirty contaminated water into clean, pure, drinkable, healthy water using different elements or techniques already in use in municipal water treatment plants. It also seemed that filtration technology and components were easily and readily available and you could get off the shelf components at affordable prices, being used even in household water filtration systems.
Shrink it down!
So what if these components could be shrunk down into a tiny size? what would be the smallest size that a filter could be manufactured so that costs are driven down so that it has fewer components, so that it’s portable, lightweight, reusable or recycled so that it could be produced in large quantities? The idea was to reduce the size of available filters from household systems into a tiny filter that would fit inside a water bottle and that could be screwed into any regular plastic bottle.
To prototype this idea I used a regular half a litre PET water bottle and attached to the cap a 10 cm piece of PVC tube filled with granular activated carbon and sealed with a small round piece of cheesecloth at the end. Making this rough prototype in a few hours was useful to learn more about the basics. It was hard to suck up water due to the compact nature of activated carbon and the diameter of the tube that influences the flow of water. However, it was the first step to show how the filter could work using other materials like ceramic or membranes.
So this is how this project started, trying to find a way to clean water using a portable device, that could be used in remote places and that could be extremely low cost so that it’s affordable even in poor rural areas where it’s needed.
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