in Lyon, composting is already becoming a common practice

More and more food waste collection points are being developed in communities. This will be an obligation from January 1st. The metropolis of Lyon has taken the lead since 2021.

From January 1, 2024, all communities will have to offer sorting of bio-waste at the source. Compost points will be deployed to allow residents to deposit their food waste. Double advantage: reducing the size of our bins and offering farmers enriched land at the end of the day. In Lyon, the metropolis led by environmentalists did not wait and has been deploying this system since 2021.

It all starts with brown bollards which have taken over the sidewalks of Lyon and Villeurbanne. There is one every 150 meters, 1,300 in total for the moment, across the city. Florent takes his family’s food waste there once a week on average. He lives in the city center: “We can also put the meat, the bones, all the vegetable peelings. Even the remains of the plates. Here we take that down, we put the kraft bag in it. I wasn’t necessarily ready to make compost in an apartment with the constraints that it represents, I think it’s excellent, it’s what I was waiting for to make compost in the city.”

In fact, you can throw away almost everything. Isabelle Petiot is vice-president in charge of waste reduction: “Here we accept all food waste. We are in the deployment phase but we have exceeded 100 tonnes collected per week.” “The big priority, she continues , it’s really about allowing residents to reduce their waste given that food waste accounts for almost a third of household waste bins. The idea was also to recycle this waste since it is currently sent for incineration. It’s almost just water so it’s an aberration. There we divert them from incineration and make them into a real natural fertilizer which enriches the soil.”

The fermentation process

Sorting is not done in the city center, especially as the operation is slightly odorous. This is the fermentation process. It is done in Ternay, 10 km south of Lyon, on an industrial platform owned by the Racine company. Florian Delorme is responsible for the site: “You can smell fruits, vegetables, things like that that are decomposing. It’s purely natural.” On site, a truck deposits the bio-waste, at the back a heterogeneous mixture flows: “We see fruit juice, vegetable juice. We see pumpkins, salads, glass bottles unfortunately, some plastic bottles, shoes. We can find things that do not compost and which have nothing to do with them. to be done on a composting platform.”

Undesirables represent 10% of the mass arriving on the platform. A machine will extract them from the mass before the composting process begins: “The bio-waste is emptied directly onto the ground and is immediately covered with ground green waste. They will be mounted in windrows which are small hill shapes. These windrows will naturally rise in temperature to reach 75/80 degrees. Once per month we return to the windrow loader to oxygenate them since the bacteria need humidity and oxygen to degrade the material.”

The process lasts just four months between the moment the peeling is thrown into the terminal and its sale as reusable compost: “It is a land which is rich in the elements nitrogen, phosphorus, potash. Users find it there because it is always much cheaper than chemical fertilizers which are often produced abroad.“And the activity is only growing. The Racine company will have processed 7,000 tonnes of compost in 2023, which is twice as much as last year.

Compost purchased by local actors

The cycle is short and so is the circuit since the compost is purchased by local players! Racine customers work a maximum of 80 km from the platform. 80% of them are market gardeners and wine growers. The remaining 20% ​​are either landscapers or individuals. All the way downstream of the compost chain in Beaujolais, in Sarcey, there are the vines of Mathieu Subrin: “The advantage is that these are local products which have a minimum transport cost. We do not need to bring composted manure from further afield. It is the addition of organic matter which allows us to bring food to the vines and to keep the soil alive so that it can retain water, the elements which are important for the vines.”

“We say a lot that agriculture pollutes and well we are more and more virtuous, we pay attention to our practices we have plenty of solutions at hand. We just have to pay attention to them.” A solution with a future. Within a year, the entire Lyon metropolitan area (1 million 400,000 inhabitants) will be able to compost its food waste.