After more than 10 years of gestation, the City of Quebec launched its food waste collection on Tuesday. The 86,000 tons of waste collected each year must be used to feed the mechanical stomachs of its biomethanation center, one of the largest in North America, whose completion amounts to 210 million dollars after numerous cost overruns.
The distribution of collection material began in the borough of Haute-Saint-Charles on Tuesday. It must continue gradually until it covers the entire territory of Quebec, plus the outlying towns of Saint-Augustin and L’Ancienne-Lorette, by April 2023.
The collection, in Quebec, already has its own color. The mauve of the bags replaces the brown of the bins, since the city has chosen to turn its back on this symbol “used throughout Quebec, and even throughout North America”, points out Mathieu Fournier, director of the municipal waste management division.
“Why didn’t we choose the brown bin? In the plex, multiplexes and condos, it has a very uneven performance, even very, very weak, explains Mr. Fournier. People don’t like to share those bins. They don’t necessarily want to see the neighbor’s lobster. »
Quebec has developed a collection method adapted to its reality, where 62% of residential buildings have more than two dwellings. Each household will have its own white bin, free of charge, designed to accommodate purple plastic bags intended for food waste. Once filled, these bags will join the other waste in the bin. Trucks will pick up food scraps along with other garbage.
The method, underlines Mayor Bruno Marchand, “will make it possible to avoid the addition of 50 truck trips per day. So we avoid the production of 3150 tons of [gaz à effet de serre] per year “.
Purple bags, from home to biomethanization
The bags themselves have been the subject of special care to ensure efficiency and reliability. Their suspenders required the importation of a machine from Italy, specifies Mathieu Fournier, and 95% of them resisted trips on board garbage trucks.
The sorting instructions are intended to be as simple as possible for the population. “Anything that is eaten and everything that is part of what is eaten goes into the purple bag,” summarizes the municipal councilor responsible for residual management, Marie-Josée Asselin.
The bags will end up in the biomethanization center, the largest of its kind in Quebec, capable of processing 86,000 tons of food waste per year and 96,000 tons of materials from the wastewater treatment plant.
To isolate the bags of food residues from other waste, a recognition system will allow them to be tracked as they pass through the intestines of the biomethanation center. Food residues will get to their destination thanks to air jets that will propel the purple bags to their destination.
A machine dubbed the “tiger” by Carl Desharnais, director of industrial project services and recovery at the City of Quebec, will then have the task of sorting out the undesirables that are found among the undesirable food waste. The goal: to extract the smoothie of food, or the pulp”, conducive to the production of biogas.
The City of Quebec aims to produce 10.2 million cubic meters of natural gas per year thanks to its biomethanization center. It has entered into a 20-year purchase agreement with Énergir which should make it possible to absorb part of the 150 million dollars that the City has invested in the adventure.
Big bill, big ambitions
Initially, in 2014, the biogas center should cost 125 million dollars. Eight years later, the bill stands at 210 million, ie 155 million for the construction of the factory itself and 55 million for the collection of food waste.
The amount is high, as are the ambitions of the City, which dreams of reducing the waste production of its population by 40%, even 50% and, thus, considerably reducing the use of its incinerator, a major generator of pollution. in the nation’s capital. “At a time when every gesture counts to deal with climate change, I think that every citizen here has all the levers to reduce what we send to the incinerator”, says Bruno Marchand with satisfaction.
However, some elements still need to be refined. The City, for example, is looking for ways to recycle the plastic bags needed to collect food waste. “In the middle of 2023, we should be fixed”, assures Mathieu Fournier.
The recovery of digestate, a fertilizer resulting from the biomethanation process, is also still the subject of studies. The City intends to produce 73,000 tons annually, but is still trying to find a way to valorize it in order to put it on the market. “It’s an expense for the moment, says Carl Desharnais. You have to start by producing it before you can improve it and be able to sell it. »
“It won’t be perfect”
Only a handful of cities in Quebec have erected a biomethanation plant to manage their organic waste. Saint-Hyacinthe has had its share of problems, largely due to the treatment of green waste – branches, grass, dead leaves, etc. – that the City of Quebec will not process in its centre.
The mayor of Quebec, Bruno Marchand, serves this warning. “We are in a commissioning that will last six months. There will be challenges, there will be issues, it will not be perfect, and I assume completely, he said. We prefer imperfection to nothingness. »
Food waste collection will begin this week in the borough of Haute-Saint-Charles. The deployment of kitchen bins and purple bags will then continue in the boroughs of Charlesbourg in December, Sainte-Foy, Sillery and Cap-Rouge in January, Rivières and the city of L’Ancienne-Lorette in February, then Beauport and Saint-Augustin-de-Desmaures in March. La Cité-Limoilou will close the march in April 2023.
The success of the biomethanation center will depend on citizen participation, remind Councilor Marie-Josée Asselin, before concluding with a call for general mobilization. “To your bags and your bins, citizens! »