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Green energy in the form of biogas is currently being used at Cascades' Rolland facility to produce fine paper. Use of this energy not only allows for significant environmental safeguards, but also fo...


February 1, 2007
By Pulp & Paper Canada

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Green energy in the form of biogas is currently being used at Cascades’ Rolland facility to produce fine paper. Use of this energy not only allows for significant environmental safeguards, but also for important benefits with respect to social and economic considerations.

The biogas that results from the decomposition of non-recyclable waste is recovered by the Intersan firm at the Sainte-Sophie landfill site, thereby preventing its release into the atmosphere. Gaz Mtro then sends it by pipeline to the Cascades plant. The collected biogas constitutes a large part of the energy needed to drive the equipment that produces the steam required to manufacture paper.

This innovative project is a natural initiative for an ecologically minded company like Cascades. The firm was founded with a mandate to recover old paper and paperboard materials and make new paper and paperboard products from them. Founder of the company Mr. Lemaire Sr. transmitted his values in terms of respecting the environment and taking initiatives to his sons Bernard, Laurent and Alain, each of whom, in their respective terms of heading the company, applied these values in the daily management of the firm.

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Cascades views the environment as a total entity and each element of nature must be taken into consideration. Safeguarding water sources, forests, the air and the soil is therefore a daily concern with respect to both manufacturing processes and the raw materials used to manufacture products.

Ecological loop

The biogas project involves an ecological loop. Consumers and industries produce recycling and waste. Cascades then uses the old, recycled paper to make new paper. Waste materials are sent to the landfill site and generate biogas, which Cascades also uses to manufacture fine paper. The manufactured paper then returns to consumers and industries, who once again recycle it after it has been consumed. And so, the process continues.

This example of an ecological loop is a concrete representation of sustainable development that makes it possible to reduce the impact on our planet by recovering and reusing energy and raw materials. This is why use of Cascades’ ecological fine papers is a simple and concrete way to take part in sustainable development efforts.

Partnership

The biogas project was made possible through the participation of three partners. Intersan, a subsidiary of Waste Management, manages the landfill site and captures the biogas. In this way, the firm has a large quantity of potential green energy at its disposal. Gaz Mtro, with proven expertise in energy transport and distribution, is responsible for safely bringing the biogas to the Cascades plant. The search for new opportunities was a prime reason for wanting to take part in this project. Finally, Cascades then uses the biogas to operate its steam-generating equipment that is required to produce paper. Through these partnerships, Cascades has found a way to make the best use of alternative, economical and ecological energy sources.

Discussions spanning more than two years resulted in an initial 10-year contract. This three-way agreement, unique in Qubec, allows for the local conversion and use of an energy resource that directly benefits the community and that would otherwise be lost.

Technically speaking, other Cascades units contributed to installing this new equipment. A large number of professionals were personally involved in the project, including pipefitters, electricians, and environmental, instrumentation and purchasing personnel. Significant support also came from the Cascades Energy Action Group and Cascades Ingnierie et Produits. Lastly, external teams were hired to carry out civil and mechanical engineering work.

Major obstacles included the limited timeframe and space, as well as difficult weather conditions. Of course, the budget also had to be respected and there had to be minimum impact on paper production.

The investments needed to implement this project are roughly $10 million. Cascades has invested more than $2 million to convert its equipment for biogas use. Constructing a conduit to link the landfill site to the plant and building a compressor station together cost $8 million. Despite these significant amounts, the return on investment will be realized over the short term.

Process

The gas emitted by residual materials consists primarily of methane (CH4), which is extremely harmful to the ozone layer when released into the atmosphere. For this reason, it is captured and burned, and transforms itself into carbonic gas (CO2), which is 21 times less harmful to the atmosphere. If the gas is not required as energy, it is then discharged into the atmosphere. Given that landfill sites will always be filled with waste, biogas constitutes an energy form that is widely available and would otherwise be lost.

It is next necessary to compress the gas in order to transport it. In the case we are looking at, a station containing four compressors sends it a distance of 13 km in 10-inch steel conduits.

Once it reaches the plant, the biogas is burned to produce a large quantity of steam required for paper drying. This thermal energy primarily replaces fuel oil and natural gas. Cascades plans to use this green energy to meet 75% of its thermal needs, depending on the amount of biogas available.

Safeguards

The three components involved in sustainable development — the environment, the economy and social considerations — have achieved from substantial benefits thanks to the biogas project.

Financial savings have been achieved since the competitive cost of biogas will enable Cascades to meet a major portion of its St-Jrme plant’s combustible needs for the next 10 years while reducing its energy costs by approximately 30%. This also allows for expanding the range of energy possibilities and thereby enjoying greater independence.

Environmental safeguards are possible because using biogas allows for the considerable reduction of energy consumption and production of greenhouse gases. Capturing and burning biogas prevents the discharge of 470,000 metric tons of carbon dioxide per year, while the use of biogas at the Cascades facility allows for reduction of CO2 discharges by 70,000 tons annually. This constitutes a 50% reduction in atmospheric emissions in the Laurentian region and is the equivalent of pulling 120,000 cars off the roads each year.

Social benefits have also been achieved because the project has contributed to the protection of quality jobs in competing industries, such as the pulp and paper sector.

Lastly, improvements have been realized in terms of performance. The modernization required for adapting to biogas equipment has led to renewing the stock of boilers. Greater stability has been achieved and the thermal station’s efficiency has improved to 82%, with the figure rising to 87% with use of the condensation economizer.

Cascades takes the concept of continuous improvement very seriously. A project aimed at recovering CO2 at the chimney outlet is currently being analyzed. The CO2 would be converted into precipitated calcium carbonate (a component of paper), in order to be used in the manufacturing process. This, too, would eliminate more than 50% of current CO2 emissions.

Julie Loyer is the communications coordinator and Michel Labont is the energy coordinator at Cascades, Rolland Division in St-Jrme. This article appeared first in French in Les Papetires du Qubec, December 2006.