Picton’s Lehigh Cement proposes use of alternative low-carbon fuels

In an effort to mitigate effects of greenhouse gases at the Lehigh Cement plant in Picton, the company is examining alternative low-carbon fuels (ALCFs) as part of its operations at the facility on County Road 49, just north of Picton.

Lehigh intends to replace and supplement the use of fossil fuels required to make Portland cement at the plant.

In a second public meeting last week, about 30 participants tuned in virtually, including some from the project team from Picton, Canada and the United States.

The first public meeting was held virtually on April 7, a month after the company made a presentation to the Prince Edward County Environmental Advisory Committee outlining their proposal for the plant.

It was noted 84 comments were received from members of the public during the first meeting, as well as 14 emails received prior to the meeting, and nine comments received after the meeting.

According to Nadia Dabagh, environmental planner with WSP Golder, some of the concerns raised included transportation and storage of ALCF materials, an enquiry about tire fluff, the impact on County Road 49 due to additional truck use, greenhouse gas reduction and potential impacts on water and air.

Thorough and extremely technical in its presentation, Thursday’s meeting provided an in-depth overview and background to the proposed changes, the permitting process and timeline, including the results of various technical studies.

They described how cement is made at the plant, some basics about clinker and concrete, sustainability and climate change, as well as the environmental impact factors, especially as it relates to green house gases (GHGs).

Lehigh has initiated the technical process which also involves an amendment to the Environmental Protection Act, in a bid to permanently use ALCFs at the facility.

The intention is to use up to 200 tonnes per day of ALCFs at the Picton plant to reduce the amount of coal and petcoke used at the facility.

It was noted the Picton plant has already achieved a near 20 per cent reduction in CO2s per tonne of cement.

One-third of CO2 emissions result from combustion of fuel and these, it was reported, can be reduced with ALCFs; two-thirds of CO2 emissions result from calcination of limestone to lime.

ALCFs have been used throughout the world for decades, where it was noted North America is lagging behind Europe in adapting to the technology.

It ws noted ALCFs are in use in many cement plants all over the world and represent a state-of-the-art technology to reduce GHG emissions. The use of ALCFs was called a key component of Heidelberg Cement’s global carbon reduction strategy and diverts non-recyclable materials from landfills.

ALCFs are in use in Ontario in five other cement plants, one of which uses up to 400 tonnes of ALCFs per day (200 tonnes per day is proposed for Picton).

The production of cement and concrete is an energy-intensive process and Lehigh Cement is a large emitter of GHGs.

Operating in 50 countries, Lehigh Hanson Materials Limited, a part of Heidelberg Cement, uses core, petcoke and natural gas for the production of clinker. The Picton plant currently uses coal, petroleum coke (petcoke) and natural gas in its operations.

“Especially coal and petcoke, although they are widely used in the cement industry, they are high in carbon, thus they produce a lot of greenhouse emissions,” said Carsten Schraeder, plant manager at Lehigh in Picton.

“For this reason, we are trying to use now up to 200 tonnes per day of ALCF to replace this power of coal and petcoke, and to reduce the greenhouse gases at our facility.”

He said the use of ALCFs at the Picton plant supports their GHG emission reduction targets.

“It will certainly support the Canada 2030 emission reduction plan, and also the Ontario plan for the need for reducing landfill sites.”

It was noted the cement industry is responsible for 7 to 8 per cent (corrected from first post) of CO2 generation in the world.

“It basically tells us we have to do something,” said Schraeder.

He noted that cement and concrete are often used interchangeability, where he clarified cement is an ingredient of concrete and is the binding element in the concrete.

The Picton plant is a cement plant, not a concrete plant, he added.

The basics of cement is clinker and consists mostly of calcite limestone, plus a little alumina, silica and iron oxide, and raw materials which goes through a process where it crystallizes to forms dark pebbles.

“Clinker is the result of the burning process in a high temperature kiln,” explained Schraeder.

The clinker pebbles are milled and ground into a fine powder, blended with limestone and gypsum, to generate cement.

The limestone used in the process comes from Lehigh’s own quarry located on the north side of County Road 49.

“We excavate the limestone, we crush it and mill it into a fine powder and feed it into a rotary kiln, generating temperatures of up to 2,000 degrees which partially melts the material and produces the clinker.”

The clinker is cooled, combined with gypsum and limestone, ground to make the cement which is shipped from the site by boat or by truck.

“At our plant, we make the cement which is then shipped to ready-mix plants where the concrete is actually made,” explained Schraeder. “It is then mixed with sand and gravel and combined with water where it becomes slurry which hardens and forms actual building materials used for foundations, slabs, patios, masonry work, etc.”

He noted concrete is the second most used material in the world, after water.

“Cement is a really important, a really useful and really efficient building material,” added where Jasper van de Wetering, alternative fuels CO2 manager for western Canada.

About one-third of CO2 at the Picton plant is coming from the combustion process of fuel, Schraeder said.

One of the commitments of the parent company is to be net zero for emissions by 2050, at the latest.

Technical issues prevented public interaction as the chat feature was not functioning, meaning the question and answer area was inaccessible for viewers. Anyone with comments, feedback or questions may email them to LehighPictonALCF@golder.com

A few people were able to email questions during the meeting. Questions included asking where the new storage facility would be located, emissions, whether refuse-derived fuels will be used, how ALCF emissions compare to natural gas, as well as the health impacts of emissions from burning ALCFs.

ALCFs are fuels that have a carbon dioxide emission intensity less than coal or petroleum coke when combusted, and must be either wholly derived from or composed of materials that are biomass or municipal waste or a combination of both, or are wholly derived from or composed of organic matter, a plant or micro-organism and grown or harvested for the purpose of being used as a fuel.

Recyclable material is ineligible for use as an ALCF

Those materials to be proposed to be used in the ALCF process include construction and demolition materials (primarily wood material with minor amounts of non-recyclable paper and plastic), industrial, commercial and institutional materials (primarily non-recyclable paper, plastic and textiles, but including wood material), and tire fibre and fluff, the combustible fraction of non-recyclable household waste (referred to as refuse-derived fuel), and discarded treated seed.

ALCF examples include non-recyclable plastics and composites, construction and demolition, non-recyclable paper and wood, biomass fuels (sawdust, wood chips, discarded seed), and other (treated wood, shingles and non-recyclable rubber).

Those fuels that are ineligible as ALCFs include soil composting materials and leaf and yard waste, electrical equipment and components, tires (except tire fluff), asbestos and hazardous waste.

“We are looking to utilize some of the plastics, organic material, paper, construction and demolition materials, that would normally go to landfill,” explained Ray Nobles, alternative fuels manager from the US corporate office. “We want to actually utilize it as a fuel to replace some of our fossil fuel usage at the Picton Cement plant.”

Some of the ALCFs being considered are construction and demolition materials (wood material with minor amounts of non-recycled paper and plastic) which will be shredded.

Another source of ALCF is industrial and commercial manufacturing sites (non-recyclable paper, plastic, textiles) which is again shredded and turned into a fuel to use.

“These are things that have a heat value of non-recycle grade that would otherwise go to the landfill which is shredded into confetti-type material and used as a fuel,” said Nobles.

The combustible refraction of household waste it was noted is not known to be available as an ALCF in the Ontario market, and there are no plans currently to use it.

Discarded treated seed can also used as a fuel.

“There are two seed manufacturers in Ontario that produce seed every year for the farmers, and every year they tend to over produce to make sure they have enough supply, and they also have rejects back from the farmers,” he explained.

The use of ALCFs will result in the reduction of use of coal and petcoke at the facility which arrive by boat, according to Nick Papanicolaou, environmental manager with Lehigh Cement in Picton.

“There will be an increase in the truck deliveries accordingly to supply ALCFs,” said Papanicolaou.

The use of ALCFs at the Picton plant will require the building of a new covered storage building and conveyancing equipment to be located next to the existing two storage domes on the site, in close proximity to the plant.

“The storage facility has been foreseen to allow for truck delivery to back into the building, unload, and drive straight out,” explained Papanicolaou. “In this way, we can reduce any risks of dust and any emissions from ALCFs delivery system.”

He said additionally the concern for noise will be further mitigated with all operations taking place inside the building.

van de Wetering spoke to sustainability and climate change.

“The primary and the only reason we are switching from coal and petroleum coke to ALCF is to reduce emissions from the Picton Cement plant,” said van de Wetering. “The reason why we are doing this is to improve the CO2 emissions.”

He also noted that by using ALCFs to replace coal and petcoke reduces emissions at the plant, but it also reduces emissions at the landfill.

“Currently, the materials that we will be using as fuel, are being sent to landfill where they slowly but surely decompose into methane,” he said.

He reminded that methane has a global warming potential 25 times greater than CO2.

“The amount of CO2 equivalents reduced from the avoidance of landfill gas is already greater than, or equal to, the amount of CO2 that is reduced,” said van de Wetering. “So for this reason, and others, Ontario has developed a circular economy plan for waste going to landfill.”

Jamie McEvoy, quality engineer with WSP Golder spoke to noise sources and guidelines and emissions, noting there wouldn’t be a significant change in noise when using ALCFs.

He said they expect only a negligible change in emissions.

He said emissions from a kiln stack include excess water and air, and products of combustion (CO2 and water), as well as by-product contaminants, including ammonia.

In terms of traffic, it is anticipated there will be 6-12 trucks associated with the transport of ALCFs per day containing the 200 tonnes coming to the facility. This traffic will be limited to daytime hours, Monday to Friday, 7a.m.-7p.m., with the bulk of the traffic (75 per cent) coming between 9-3p.m., with about one truck per hour.

The trucks would come via the 401, through County Road 49 to the facility and back the same way, avoiding any incremental traffic through Picton.

“The dispersion of the incremental truck traffic that is generated should not result in any noticeable traffic impacts along Highway 49 or that within Picton,” said Papanicolaou.

van de Wetering said the next step in Picton would be to commission natural gas burners to replace coal and petcoke.

“That is already happening and as much as 25 per cent of the energy to make clinker in the near future will come from natural gas,” he said. “And natural gas has already half the greenhouse gas impact of coal and petroleum coke.”

The Picton plant consumes about 2.8 million gigajoules of energy per year.

“The numbers add up pretty quickly when you are using coal and petcoke,” van de Wetering said. “A lot of energy is required to convert limestone and clay-type materials into clinker.”

It is expected Picton’s Cement plant will reduce its CO2 by 46,228 metric tonnes per year.

To put that into context, just one tonne of CO2 is released to either heat a home for four months in Canada, or by driving a car for 4,500 kilometres, or a year’s garbage for one household, or raising a cow for six months.

Next steps include receiving and reviewing additional comments, the completion of the technical studies, and submitting all application documents to the ministry (possibly in October). A decision is expected to come from the ministry within one year.

Due to the technical issues preventing a question session at the meeting, Lehigh has planned an open house at the plant (1370 Highway 49) https://goo.gl/maps/TpLJvnbbiANnusJ3A for Wednesday, Aug. 31, at 5p.m. for a further opportunity for members of the public to ask questions, or present concerns. Information and all technical reports are posted at http://lehighpictonalcf.ca/.

Comments and questions can also be received via email until Sept. 15 at leighpictonalcf@golder.com