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BioReactor
Laflèche Environmental's BioReactor puts waste to work

By combining the natural containment properties of clay with cutting-edge technology and a strong vision of a cleaner, more sustainable future, Laflèche Environmental's BioReactor is changing the way we think about waste.

The premise of the state-of-the-art landfill site known as the BioReactor is to view waste as a valuable asset. Proceeding from that premise, the BioReactor is designed to contain all waste - and waste water - on site, and to treat the waste to ensure it continues to provide benefits to society for decades to come.

When waste arrives at Laflèche Environmental, it is laid inside of an impermeable, natural clay bowl that is lined with high-tech fabric and drainage stone. As the waste deteriorates, the resulting wastewater, known as leachate, is contained by the clay and lining and flows into a large sump in the middle of the bowl.

The leachate is then separated into two streams. One part is re-circulated into the waste bed from which it came. The rest is pumped from the sump into a complex treatment system.

Accelerating decomposition

Re-circulating the leachate encourages an accelerated anaerobic reaction within the waste. Microbes, the microscopic "bugs" that break down the waste, act much faster in an anaerobic environment. By re-circulating the leachate, the BioReactor can accelerate the decomposition of waste by as much as 15 - 20 years.

This means that waste can break down nearly three times as quickly in the BioReactor as in a traditional landfill, where decomposition takes an average of 50 years.

Reaping the benefits

Once a cell, or section, of the BioReactor is filled with waste, it is covered with a soil cap. As the waste decomposes, methane gas is created and held under the cap. When it is present in sufficient quantities, the methane can be captured and used to generate electricity - and not just a little electricity, either.

Over its lifetime, we believe the BioReactor will produce enough methane to power at least 1,000 homes for more than 50 years. In addition to its environmental value, this makes the BioReactor a tremendous economic asset for the area.

We expect to being harvesting methane in fall of 2006.

Long-term thinking

The long-term plan for the BioReactor is to further capture heat and carbon dioxide, the two byproducts created in the generation of electricity from methane. They will be used to warm greenhouses erected on the site and to provide them with an enriched carbon dioxide atmosphere to enhance plant growth.

Once the anaerobic cycle is complete, it may also be possible to recover soil and recyclables. This will empty out the BioReactor's cells, leaving them available to take in fresh waste.

By managing the BioReactor in this way, we will be able to continue the cycle of putting waste to work for many decades - perhaps for as much as 100 years.

Laflèche Environmental has conducted research with two universities to study the sustainability of using tire shreds to replace stones in the BioReactor's drainage layer. With the successful completion of the study, Laflèche Environmental has been fully sanctioned by the Ministry of the Environment, and holds a Certificate of Approval allowing for the processing of 3,500,000 tires per year. This represents more than one quarter of all scrap tires generated in Ontario annually and makes us the largest processing facility in the province. This project will allow us to conserve a huge amount of stone - approximately 15,000 tons per year - and further reduce our environmental footprint.

Click here to see the BioReactor in Action.