#biosand

[materialsworld]

OHorizons’ BioSand Filter, a development of the traditional slow sand filters, uses a biofilm to help combat the spread of pathogens in drinking water, either by non-harmful organisms directly consuming pathogens or starving them of food and oxygen, causing them to expire.

While most BioSand Filters are made using steel moulds that cost between $500-2,000, OHorizons’ wood mould costs around $70-100, potentially allowing greater proliferation of the device.

We profile OHorizons’ BioSand Filter in our water filtration article in the next issue of Materials World, which you can check out on the IOM3 website soon.

[innocencelostfoundation]

We are very excited to be partnering with Clean Water International, Biosand Philippines to bring bio sand filters to our community centre in Kabala, Sierra Leone! This will allow our water to be purified and filtered! We envision the project spreading throughout the community and beyond so that each home may have a water filtration system. Clean water for life! #WorldWaterDay #cleanwater #cleanwaterint #biosand #biosandfilter #waterfilter #SierraLeone #Aftica #filtrationsystem #water #kabalacommunitycentre @cleanwaterinternational @cleanwaterphilippines

[ourworldthroughalens]

Water for Life

Since the economy was destroyed during the Khmer Rouge regime, Cambodia, one of the least developed countries in Southeast Asia, has had difficulty improving infrastructure. Although water is abundant, access to clean drinking water is one of these hardships. Tap water is not potable, and groundwater is frequently contaminated with arsenic. More than 40% of the rural population uses unimproved…

View On WordPress

[trailblazerfound]

BioSand Bag Project update from Cambodia www.thetrailblazerfoundation.org

[innovationcolab]

Project Notebook - Biosand Filter Part 2: Completion of the Proof of Concept

This is the completed biosand filter after the second revision. This is a proof of concept demonstrating that a 3D-printed mold can be used for concrete.

There were numerous improvements over the past filter. The 3D printed parts were redesigned such that they were easily removable after use, instead of being glued into one piece that adhered to the concrete too well. There was also much less use of mechanical ties such as wood staples; instead painters tape more than sufficed to hold the mold together. Instead of plastic sheeting covering the concrete-side of the interior and exterior mold, a form release agent made up of a combination of mineral spirits and petroleum jelly was spread onto the concrete, making it easier to remove as well as much faster to apply.

Additionally, the concrete mix itself contains far more water (often a quart or more for each bag). This allows the concrete to run into spots and harden into a solid block, instead of acting as many pieces of gravel. The amount of water that is used in the concrete mix can be seen in the below image.

The water pools at the top of the concrete as the concrete is saturated with water. This is accurate with other concrete pours from other people. Since I left the filter to dry for three weeks, the amount of water remaining is trivial.

One problem that I did experience is vibrating the concrete before it dried. Since the base of the filter is very small compared to the exterior mold, I was unable to screw in secure supports. When I stuck the vibrator in the concrete, the mold broke and the concrete poured out the broken sides. This happened twice before I decided to screw in as many steel fasteners to the sides together as I could and not vibrate the concrete. This worked and while the concrete did shrink some and contain bubbles, it did dry together successfully.

This project is complete and is awaiting pickup from the nonprofit. Possible next steps include a fully-3D-printed biosand mold on a large-scale 3D printer, which would cost around $5 and would be reusable. This would enable modularity as well as prototyping of unique aspects (vibrator attachment on the side of the exterior mold, handles, etc.). Water tanks/raised granary stands can also be made as well.

I’m quite happy with how this project has turned out and look forward to seeing how 3D printing and international development will work together at Duke in the near future.