Two students made compostable water filters from food scraps

Pratt Institute graduate students Charlotte Bohning and Mary Lempresfrom Studio Doppelgänger, have created Strøm, compostable water filters made from food waste.

They are a carbon filter made without fossil fuels, from kitchen scraps. You can use Strøm filters like replaces Brita cartridges, or add purifying filter bars to water bottles or glasses. There’s even a self-cleaning carafe.

How it works?

These filters use activated carbon, but instead of coming from petroleum, the source is a form of natural biochar. It is mixed with natural resins to form a thermoplastic.

The compound acts as a filter or container. At the same time, it opens up a new horizon of options for water filtration and storage. Besides, reduces the need for single-use plastic filters that end up in landfillsabout 100 million each year.


Böhning and Lempres burned banana peels, sheep bones and other waste from their kitchen, local farms and restaurants in an oven.

This “pyrolysis” process prevents the carbon in the biomass from forming carbon dioxide when burned. Instead, it turns it into a porous, absorbent carbon that stores carbon from food instead of releasing it into the atmosphere.

Carbon sequestration was one of the main objectives of the project. Even when these filters finally reach the landfill, they will still store carbon. They will not produce methane like food waste.

Biochar and bee propolis are combined with tree resins to create these flexible shapes that can be melted, injected or molded into cartridges or real Strøm water jugs.

The end products claim to outperform traditional filters and work to filter out various substances that don’t react to activated carbon.

The biochar is magnetized in a bath of ferrous salts to extract heavy metals from the water. For its part, the animal bones contained in the charcoal filter the fluoride.

Propolis and tree resin prevent the accumulation of bacteria and act as binders. It’s great, really.

Bees use propolis to mummify the corpses of hive intruders and stop the spread of disease. This means propolis can be used for a number of antimicrobial, antiviral and antifungal applications.

Filters break down in the ground in about a month. Plastics typically take 11 generations to break down and release polluting chemicals. Biochar, on the other hand, can be used as a fertilizer or as a carbon sink.

Going through

Leave a Comment