In Corrèze, more than 22 tonnes of nitrous oxide have been seized, or more than 4,000 bottles. The phenomenon therefore extends well beyond the Haute-Savoie department alone.
In Annecy, in Haute-Savoie, one to two explosions occur every day in a waste treatment plant. They are caused by nitrous oxide canisters thrown out with household waste.
The furnaces are damaged. The doors are sometimes blown off by the blast. An explosion in a waste incinerator has already been caused by such a canister.
When a canister arrives in the furnace, the pressure and heat trigger an explosion. The plant must then interrupt or slow its activity to inspect and repair the facilities.
These canisters contain nitrous oxide, a gas inhaled using balloons. In theory, they must be taken to a recycling center and not end up with household waste.
Nitrous oxide, often called laughing gas, circulates in the form of cartridges or canisters. Once empty or abandoned, they too often end up in garbage bags.
In Annecy, the rate of one to two explosions per day illustrates the scale of the problem. The plant continues to process a high volume of waste while managing these repeated incidents.
Operators observe repeated damage to equipment. The furnace doors, designed to withstand heat, cannot hold up against the sudden blast.
Sorting instructions exist: these pressurized containers are classified as specific waste. Their presence in the household waste stream turns an incinerator into a daily risk zone.
These blasts create significant logistical problems on the site, which processes 100,000 tonnes of waste per year. An explosion in the furnace can cause the plant to shut down.