Incinerator in Toulouse: a dilapidated but “not dangerous” factory
An ash silo collapsed Monday in the Toulouse household waste incineration plant without causing injury. In a few years, this factory will be more in line with environmental standards and a debate on its future is scheduled by Decoset.
An incident occurred Monday, at 6.30 a.m., at the household waste incineration plant, route de Seysses, in Toulouse. A minor incident that took place under the spotlight of a factory which was built in 1969 and which will soon no longer meet environmental standards for the emission of nitrogen oxides. Decoset, the owner’s mixed syndicate, which brings together Toulouse Métropole and other communities, has therefore planned heavy investments but also a major debate on the future of such an infrastructure which, moreover, thanks to two heating networks, provide in heating and hot water 35,000 housing units in the Pink City.
Each year, the incinerator, which includes four ovens, burns around 285,000 tonnes of waste, mainly household waste from Toulouse that the garbage trucks dump here in a large pit. Combustion, which heats the water that will circulate in the heating networks, leaves residues, clinker, which will then be treated. It also gives off, from the red and white fireplace, well known to Toulouse residents, smoke which, too, is purified to meet the environmental requirements.
These residues from the purification of combustion fumes and ashes are stored in a silo fifteen meters high which rests on a ten meter support. It was this silo, which contained 130 tonnes of ash, which collapsed on Monday while it was being emptied. “A classic operation, carried out regularly, which has never been identified as a problem,” explains Sophie Delage, general secretary for the South-West of Veolia recycling and waste recovery. The silo came to “lean” on the wall of the incinerator. Safety procedures were important with, in particular, the intervention of firefighters for technical advice and information to the State services. Rope workers secured the silo to a crane. “It’s about understanding what happened. Then we will see if we can repair or change the silo ”, specifies the manager of Veolia.
A new factory?
President of Decoset, Vincent Terrail-Novès acknowledges that the plant of the SETMI, the thermal exploitation company of Mirail, due to its age, is dilapidated. But it has been the subject of investments – 1 M € recently for the creation of a fire water retention basin – and it is “not dangerous”, he says.
On the other hand, from an environmental point of view, the incinerator will soon meet emission standards for nitrogen oxides, NOx. Hence a heavy investment of 46 M € programmed by the union.
But in the longer term, by 2030, other, more draconian standards put into play the very existence of the incinerator. So much so that Decoset has planned a major debate, probably after the 2022 elections, with the help of the National Commission for Public Debate, which has just appointed two guarantors. “Should we build a new factory or not? »Summarizes Vincent Terrail-Novès. This is the stake, knowing that Decoset has another in Bessières but that with the increase in the population, even the treatment of waste from the region, the tonnages to increase. Decoset has one advantage: if reconstruction were ever decided upon, it could be done on the same site without stopping the operation of the incinerator.
Three buildings temporarily without heating
The Mirail incinerator was built in order to eliminate household waste but also to recover the heat of combustion. A network of pipes which contains water vapor under high pressure then diffuses this heat into buildings where it brings, via an exchange device, hot water and heating. Toulouse has two heating networks. The first, which supplies the Mirail, was enlarged to the Cartoucherie, the Oncopole … A second, commissioned at the end of 2019, serves the CHU Rangueil, Empalot, Montaudran … Or, for the two networks, some 35,000 housing units. With the silo incident, the supply to the second heating network was suspended. But the back-up system of the operator Dalkia took over. So that the heating was everywhere, except in three buildings of Empalot where it was restored yesterday at 11 am.