Yellow bag, compost or gray trash. Although we pay attention to sorting our waste all year round, the end of year celebrations often disrupt everything. Because the recyclable bin is dripping with wrapping paper, plastic lives a fantastic life and the garage trash can is dripping with shrimp. And in the middle of this pile of garbage, what should we do with our empty shells? A good time for the consumption of oysters, whelks, scallops and sometimes even a few mussels, Christmas is also the scene of a massacre in incinerators or landfills. Because in the absence of an alternative solution, the vast majority of French people must resort to throwing their empty shells into their household waste. A gesture, however, far from trivial. By making your trash heavier, you increase the truck’s fuel consumption and therefore the removal bill. As for the shells, they don’t really have any calorific value when they are burned. In short, it would be good to find an alternative.
In Cancale, we throw everything into the port
In certain corners of Brittany, residents have the habit of throwing their empty shells into the sea themselves. Often to prevent the smell of cooking from imitating that of a fish market in the middle of summer. In Cancale, for example, there are tons of oyster shells that tourists love to throw from the pier after swallowing their slimy bodies with a glass of white. But let’s be honest, most often, pearly shells end their lives buried or cremated. However, several coastal areas have launched dedicated collections, often around the holidays.
In the south of Vendée, Sycodem has been organizing a shellfish collection for seven years, making available bins in the 40 municipalities of the union. First concentrated during the end-of-year holidays, it is now in place all year round at the same time as the collection of bio-waste from catering professionals. “Users questioned us about this odorous flow, which was difficult to recycle in the garden and which was bulky in the black bag,” summarizes Sophie Métay, director of the waste prevention service based in Fontenay-le-Comte. The phenomenon increased when the community imposed the incentive fee in 2018. Big shellfish eaters saw themselves penalized by the weight of their waste and quickly demanded that the service be extended all year round. What elected officials agreed to finance.
This initiative and all the others carried out on the Atlantic coast have given ideas to a good number of communities, which often get started in a very artisanal way. “We put this together quickly because one of the mayors in the area had heard about the projects being carried out in Vendée. We had just installed bins in five recycling centers and we quickly communicated to the residents,” says Anne-Laure Le Niliot. The prevention officer from Pays d’Iroise Community (Finistère) was surprised to recover two tonnes of shells in less than three weeks last year. But what to do with it? Here as elsewhere, the collected material is crushed then mixed with plant compost. “It’s a way of showing the benefit of sorting to users and giving them the material back,” recalls Sophie Métay.
Does it stink of mussels?
Everything is generally distributed free of charge to residents wishing to improve their vegetable gardens or given to local farmers. “The shell is excellent for nourishing the soil because it contains calcium. We thought it was a shame not to take advantage of it and throw everything away,” says Ronan Salaün, president of Smictom Valcobreizh, in Ille-et-Vilaine. Last year, his union collected more than three tons of shells in one month. Not bad for a first. “Our difficulty is finding outlets that are not too expensive. When we process shells, we have organic matter, we cannot do anything with it.” In particular, it is imperative that the shells are empty and that the shellfish are not mixed in them. And does it stink? ” Not really. In winter, we can go in the bin for up to three weeks before collection,” assures Anne-Laure Le Niliot. With the heat, the observation is not the same in summer.
There could be numerous opportunities in both construction and agriculture but face a problem of “hygienization”. Because for any industrial use, this process is mandatory to “clean” the material. Problem: it costs too much for communities to be able to buy into it.
Only one company in France
In Charente-Maritime, a company has dared to get started and offers to grind the shells in order to use them as a dietary supplement for laying hens. A natural technique that makes eggs more solid. Based in Périgny, the O’Vive company presents itself as “the only one in France” to reprocess oyster waste and can also transform it into aquarium bottoms, natural minerals or aggregates used by both the construction industry and landscapers. The problem is that processed products generate relatively little added value, with the cost of processing being a barrier. But at the end of the year, something tells us that the O’Vive teams are going to work hard.