**DISCLAIMER** You should always boil water from unrefined sources before drinking it. Do not rely on any filter, including this one, to make water potable. It should also be noted that 3D printed parts are not necessarily considered to be food-safe right out of the printer.
This design is a submission for the Esso Fueling Innovation 3D Printing Contest.
According to UNICEF, "In 2015, 844 million people still lack a basic water service and among them almost 159 million people still collected drinking water directly from rivers, lakes and other surface water sources."
Almost 6,700 cans are thrown away every second. This is a way to upcycle a 250ml can in a useful way. While this filter will remove large particles, it will not filter out harsh chemicals and other contaminants. With use, the filter is supposed to create a "Bio-filter" above the sand layer and begin filtering out micro-organisms, however, please see above disclaimer.
You Will Need:
Wash all components (including sand, etc) with warm water before use.
1) You'll need to print one filterv2 file and 4 filterdiv files.
2) Once printed, rinse the parts thoroughly.
3) With the filter upside down, add in one divider and a coffee filter if available.
4) Pour in 3 tablespoons of activated carbon.
5) Add another divider, coffee filter and then add 3 tablespoons of sand.
6) Add another divider, coffee filter and 3 tablespoons of gravel
7) Add the last divider.
8) Fill 250ml can with water to be filtered.
9) Snap on can to filter.
10) Tip can upside down to begin filtering the water.
TIPS: With the dividers, my printer took a LONG time to print them. You may be better off using coffee filters alone if you're short on time. Also, the filter may be more efficient with finer activate charcoal pieces. YMMV.