École polytechnique: Bioinspired student projects

An ecological packaging

Léon Rembotte and Thomas Metzger won 3rd prize for tackling an issue related to waste generated by food packaging, which is mostly made from non-biodegradable products from the petrochemical industry. The two students looked in particular for an alternative to the packaging used for the distribution of cut meat. The result of their thinking is BioWrap, a two-stage packaging process.

The piece of meat would first be soaked in a bactericidal gel consisting of long unsaturated carbon chains and salicylaldehyde. The unsaturated carbon chains prevent the condensation of water. They are inspired by the composition of the gel secreted by the solitary wasp, which thus preserves the provisions it prepares for its larvae. Salicylaldehyde, on the other hand, has many anti-microbial effects and is found in the secretions of the larvae of some beetles. The second step in the packaging process is to dip the food in a liquid wax bath similar to that of the date palm. As it hardens, it forms an airtight barrier that is resistant to moderate shocks. To open the Biowrap, the wax layer must be broken and then rinsed to remove the gel, which is nevertheless edible.



Managing household waste

Winning the Special Jury Prize, Matthieu Oriot has come up with a bioinspired solution for managing waste disposal in Dakar, the capital of Senegal. The city has no official waste collection system and a traditional solution based on large garbage trucks would be too expensive. It turns out that honey bees also have to clear their hive of waste. They do this in three stages. Collecting, compacting into small pellets and transporting them out of the hive. Another example is the lymphatic network which evacuates cellular waste from our body, without the need for a pump like the heart, but instead through the movements of the body, such as breathing.

Based on these two examples, the system imagined to treat the waste in Dakar consists firstly of collecting it at ten points using small trucks, where it would be compressed into 50 kg packets (like bee pellets). The packets would then be disposed of by private individuals on their way to and from work at five collection points (i.e. using movements that already exist, such as circulation in the lymphatic network). Finally, the waste would be transferred to the landfill. Matthieu Oriot has carried out a first approximation economic analysis of the cost of this biomimetic solution. He hopes to carry out additional studies to take this project further.

These two projects were carried out as part of Biomimetics courses (MEC574) taught by Emmanuel De Langre, Professor at École Polytechnique, within the Ingénieur Polytechnicien Program.