Burning questions at cement plant open house
Jeff Heuchert It’s not what’s going in, but what’s coming out, that was of concern to most St. Marys and area residents who attended the public information meeting hosted by St. Marys Cement last Wednesday evening at the Friendship Centre.
St. Marys Cement is planning to undertake a short-term test burn of an alternative fuel made from post-composting residual plastic film at its St. Marys’ plant; the plant currently uses a combination of petroleum coke and coal. The company is running the test burn to gather air emission data to determine the fuel’s environmental feasibility. If the results of the alternative fuel are positive, the company would consider using the plastic film on a regular basis.
St. Marys Cement is currently trying to gain approval from the Ministry of Environment for the test, however, they brought a team of experts to town last week for the first of two information sessions to answer any questions or concerns residents have over the proposed burn.
Martin Vroegh, environmental manager for St. Marys Cement, said the company wanted to hold an open consultation process to ensure that the public is not left in the dark over their plans and, more importantly, to “try and gain the public’s understanding.”
The company hopes to conduct the test burn, which will be overseen by a third party, over approximately four days, likely in December. Vroegh added that emission testing would be done on the stacks and ambient air before and after the burn.
Bridget Mills, senior environmental engineer for the company, noted that the levels of trace metals and organic chemicals when burning the alternative fuel would be very similar to current emissions results from burning coal and petroleum coke, which are already well below emission standards.
Mills said they do expect to see a drop in sulphur dioxide — one of the triggers of asthma symptoms. As for the other substances in the air, she added, “based on our knowledge of other plants with similar materials, we’re confident we’ll see virtually no change in offsite impact.”
Vroegh said there is “a clear science behind the process” of burning the plastic film, which is composed of plastic bags and plastic film from sanitary paper products such as diapers, which are allowed in some municipalities’ green bin programs.
Vroegh said the plastic film will be burned at such high temperatures —  up to 1,500 degrees Celsius — that residents should have no concerns over harmful chemicals being released into the air.
He explains that while carcinogens form between 800 and 900 degrees celsius, temperatures in the kiln quickly move past this point as the limestone in the kiln immediately consumes any available heat. He also noted that the high burn temperatures destroy any organic compounds.
Vroegh also noted that the plastic film is an ideal material, in that it is extremely light and will burn instantly. “You don’t want little particles floating down the kiln,” he added.  
St. Marys Cement’s parent company already uses the alternative fuel at its plants in the United States and Brazil, while the use of non-traditional fuels has increased considerably in Europe as well. St. Marys Cement is also undergoing the same consultation process for its Bowmanville plant, where they hope to test burn not just the plastic film, but paper sludge and a paper residue product.
In St. Marys, the company plans to burn approximately 250 tonnes of the plastic film during the test. The fuel will be delivered by truck to an enclosed temporary building, which will be kept at a slight negative pressure to prevent any odour/litter from escaping. A new temporary feeding system will supply the fuel to the kiln.
St. Marys mayor Jamie Hahn noted that, if the plant is defined as a private waste disposal site due to burning the plastic film, the company may be required to obtain an amendment to both the town’s official plan and zoning bylaw — either one of which could put a hold on the test burn. Also, the company may need a building permit to construct the temporary building.
Mayor Hahn said the town has hired consultants Conestoga Rovers and Associates to oversee the test burn. He added that his only concern was for the qualify of life for the town’s residents.
“We want solid science in what they’re going to be doing, and that it isn’t going to (negatively) affect the residents of St. Marys and area.”
In response to a concern from Mayor Hahn over the possibility of hazardous waste making its way into the plastic, Janine Ralph, service director for environmental sciences and planning for St. Marys Cement, said any hazardous waste would be weeded out through the composting process, before ever arriving in St. Marys.
“We are very comfortable with the safety of the material,” Ralph added.
Other residents’ questions centred on current conditions around the plant, such as odour and dust, and if they might be improved from burning the alternative fuel.
Vroegh explained that the sulphur content in the petroleum coke can lead to an odour around the plant, and that the plastic film would have a much lower sulphur content and help reduce the odour. As for the dust, he explained that the dust is typically from material handling sources and has nothing to do with the combustion of fuels. However, he did say the fuel would “likely improve dust conditions, albeit marginally.”
Vroegh says it’s taken close to two years for St. Marys Cement to reach this point, noting that they’ve had numerous discussions with government departments, the town and environmental organizations.
He added that in addition to the economic benefits of switching to the alternative fuel from costly fossil fuels, there would also be several environmental benefits, including avoiding landfill disposal and the reduction of greenhouse gas emissions (carbon) from burning fossil fuels.
“We feel strongly that if the environment can be improved and costs can be reduced at the same time, then this is true sustainability,” he added.