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It’s a bit like picking a dance partner.

At least, that’s the analogy that Andrew Pollard (Mechanical and Materials Engineering), Queen's Research Chair in Fluid Dynamics and Multi-Scale Phenomena, chooses when he talks about the relationship that he and other Queen’s researchers have developed with the cement giant Lafarge, in particular with its Bath, Ont., plant .

A few years ago both parties stepped on to the dance floor, very tentatively, but to take Dr. Pollard’s analogy and extend it, as they have gotten to know each other the steps and the style have improved, slowly evolving from a simple foxtrot to something as complex as a square dance with multiple partners.

Many companies pride themselves on being socially responsible, but Lafarge is particularly serious when it comes to fighting climate change. There are good reasons for this. Making cement is an energy-intensive business – the kilns that are used must be heated to 1,450 C – about a quarter of the temperature of the surface of the sun. Given how widespread the use of cement is – it’s the world’s most-common construction material – it isn’t surprising that its manufacture accounts for approximately five per cent of all greenhouse gases worldwide. As the world’s leading producer, it is estimated that Lafarge is responsible for about one per cent of all emissions worldwide. If they could reduce that number, the company could actually make a noticeable dent in the amount of greenhouse gases reaching the atmosphere.

That was what initially propelled Rob Cumming, at the time the environment and public affairs manager at the company’s Bath plant, to reach out to Dr. Pollard, who was working with the Queen’s Sustainable Bioeconomy Centre.

What Mr. Cumming offered Queen’s was a chance to experiment with a working plant to see if they could reduce the greenhouse gases being produced. The lessons learned would be applicable in other industries as well. Dr. Pollard would be joined by Warren Mabee (Geography and Planning) , Canada Research Chair in Renewable Energy Development and Implementation, and Darko Matovic  (Mechanical and Materials Engineering), an expert in fluid dynamics, among other subjects. Other Queen’s faculty involved included Neal Scott (Geography and Planning), Sharon Regan (Biology) and the late Ted Grandmaison (Chemical Engineering).

The challenge was to see if Lafarge’s emissions could be reduced by substituting new fuels for at least some of the coal and coke being burned in the kiln. For every tonne of coal replaced by a non-fossil fuel, you can get a dramatic reduction in greenhouse gas emissions, typically between 50 to 80 per cent, but sometimes as high as 90 per cent. Initial efforts focused on using what is termed “virgin biomass,” such as switchgrass or hay bales. The main challenge was that, at the time, there were no real scaled-up suppliers of such fuels. Another idea that focused on creating a fuel called the “Q-Pellet,” marble-sized fuel pellets created by heating wood in an oxygen-free environment – a process known as “torrefaction” – remains unrealized. The pellets cannot be produced in bulk. (That “Q” stands for Queen’s, by the way.)

The Queen’s researchers hit on a third possibility – using what can be termed “non-virgin” biomass – wooden hydro poles, construction debris, railway ties, used shingles. All contain varying proportions of biomass. These sorts of debris are plentiful – always a good thing in a fuel source – and using them to fire the kiln would stop them from winding up emitting greenhouse gases in landfill sites, a nice side-benefit.

David Hyndman of the Queen’s Office of Industry Partnerships had a connection with Lafarge stretching back several years – at one point he had worked for Performance Plants, a company that had been growing possible bio-fuels at the Lafarge site. On joining Queen’s in January 2012, he quickly got involved in the project from the Queen’s side, helping Mr. Cumming write a successful application for a CMC Carbon Management Grant that would underwrite the work the Queen’s researchers wanted to undertake at Bath.

Work on testing the feasibility of using these materials as fuel at the Bath plant began in early winter 2013 with the installation of equipment that could store, mix and then feed these new fuels into the plant. Dr. Mabee’s team would monitor carbon output before and after the new fuels were introduced to see whether they delivered the hoped-for carbon reductions. The full-scale test runs on the three-year pilot project began in summer 2014.

At a meeting open to the general public in June 2016, Lafarge announced that they had achieved a nearly 10 percent reduction in fuel-based carbon emissions, thanks to the use of these new fuels. The company hopes to increase this to 30 per cent by 2020.

“We’re well on track,” says Mr. Cumming. “In fact, we’re probably ahead of schedule on that.”

The cooperation between Queen’s and Lafarge has helped the company take some important steps in realizing their corporate responsibility. More, the partnership and its early success has bought them a measure of goodwill among the local community, where news that the plant was planning on burning what was fundamentally waste was greeted with some scepticism. Based on the findings of the Queen’s team, Ontario’s Ministry of the Environment and Climate Change has identified the use of low-carbon fuels as a key way for the cement industry to reduce its greenhouse gas emissions.

The benefits for Queen’s have been considerable as well. Masters and PhD students, along with post-doctoral fellows in a number of fields have been given real-life, hands-on experience – right down to sifting through dumpsters filled with construction debris to figure out exactly what can be used. The lead researchers benefit as well.

“We can see the fruits of our labours, which is very rewarding – particularly for researchers who work on big problems that live inside computers,” Dr. Mabee says.

There is still plenty of work to do – there are pressing questions about the water content in the fuel – too wet and it won’t burn hot enough to create the best kiln conditions and there may be problems with spontaneous combustion during storage. Creating a supply chain to feed this or other plants will be a challenge.

In the next stage of the project, Dr. Matovic will be looking at the burners inside the kiln to improve their efficiency at burning co-fuels – a mix of traditional coal and coke and biomass. Researchers will be taking the lead on different stages of the current project, and other ambitious projects are currently in the planning stages. The Industry Partnerships team will be kept busy coordinating researchers and projects – acting a bit like the caller at a square dance (there’s that analogy again), telling people where to go and when, and keeping all the relationships going. And soon they may be going on the road – expanding the program to other Lafarge plants. If it happens, that’ll mean new partnerships and new opportunities for Queen’s researchers.

“Lafarge is a leader in advancing alternative fuel for their industry,” says Steven Liss, Queen’s Vice-Principal (Research). “The relationship with Queen’s has garnered outcomes that are mutually beneficial and address the global issue of climate change. This isn’t the end of the relationship, either. Queen’s and Lafarge are currently working on their next venture. You could say that the band is warming up, some new, and additional partners will be hitting the floor with some exciting new steps. We are looking forward to the results.”