Domtar puts its energy to work

Staying competitive by rethinking energy

Objective: Slash operating costs with a smart energy approach using heat pumps and heat recovery

The Domtar mill has been a local fixture in Clermont, in the Charlevoix region, for close to 100 years. Each day, the plant produces some 600 tonnes of newsprint—including a lightweight paper much in demand in Europe that sets it apart in the industry—through a thermomechanical pulping (TMP) process. The company knew that staying viable called for bold measures, a mindset that has helped guide its search for sustainable strategies to reduce costs and remain competitive. One solution came from an unexpected source: waste heat from its processes. With the support of Hydro-Québec, Domtar set about rethinking its energy approach.

Nothing is lost, everything is transformed

To produce newsprint, Domtar’s mill relies on a process using steam that’s fairly energy-intensive. And that energy use naturally adds up to significant costs. “For a plant like ours, energy makes up a big chunk of our expenses,” explains Stéphane Gadbois, director of the mill. “The real challenge is finding a way to keep up production while using less energy.”

But how? The turning point came when Mario Girard, the recently appointed superintendent of energy, projects and engineering, noticed clouds of steam rising from the basement drains. “Steam: that means there’s energy there that we could potentially recover,” he thought. This moment of realization marked the start of a major transformation.

Girard and his team found that expertise at Hydro-Québec. Together, they looked into the programs offering the best financial incentives, then enhanced their original project. “The upgraded project was a perfect fit for the Customized Option of the Efficient Solutions Program explained Hydro-Québec account representative Lyne Gauvin.

Revolutionizing energy use: Heat pumps and heat exchangers at work

In a TMP process, steam comes from a steam generator, a biomass boiler, and two 28-MW electric boilers. The goal? To reduce steam usage and thereby cut down on the energy consumption of the two electric boilers.

The selected solution was brilliant in its simplicity: recover waste heat using heat exchangers and two water-to-water heat pumps integrated directly into the process. These heat pumps replaced the old chillers , capturing energy from the cooling loop and redirecting it into the paper machine’s hot water circuit.

“It’s a smart way to make the most of the energy the plant is already using,” said Bernard Bégin, commercial engineer at Hydro-Québec. “Heat pumps have been used in many industries for a long time, but applying them in the manufacturing process is a first for Québec’s pulp and paper industry. We were confident it would work, but since there were no existing references, we had to accept a degree of uncertainty about their efficiency in this specific context. Domtar took the plunge.”

Major savings, lower costs

The company’s bold move paid off: winter power demand at the plant dropped by 4 to 5 MW, resulting in annual electricity savings of 15 million kWh—roughly the yearly consumption of 880 households. The solution also cut fresh water use by about 12% during the winter months.

But there’s more. The company’s long-term financial gains are impressive: $800,000 in recurring savings each year.

Hydro-Québec’s $3 million in financial support was crucial to bringing this ambitious project to life. “We couldn’t have done it without Hydro-Québec’s support,” said Girard. “By covering 75% of the costs, it lets us recoup our investment in less than 15 months. Not to mention, we now have a model that can be replicated at other Domtar plants.”

A strategic collaboration with Hydro-Québec

By involving Hydro-Québec from the very beginning, the company got more than just financial support: it also received personalized guidance and expert advice. For instance, as a pulp and paper specialist, Bégin is well-versed in energy management best practices for mills like the one in Clermont. He was the one who encouraged the team to conduct a pinch analysis to identify heat sources and sinks. To do so, the team turned to FP Innovations, an R&D organization specializing in the pulp and paper industry.

Bégin also guided Girard and his team to CanmetENERGY, where they found a wealth of free resources, including the EXPLORE multivariate data analysis software, the COGEN modelling tool, and INTEGRATION, a heat recovery optimization software, along with training on how to use them.

He also recommended they pursue Certified Measurement & Verification Professional (CMVP) training to develop a strategy based on recognized practices for measuring the savings achieved from the project—a recommendation they followed.

The company hired two engineers, both of whom are still on staff and now working on other projects. To design the process flow diagrams, they turned to CSM Industrie Inc., a specialized firm founded by retired engineers from the plant—thus fostering local expertise.

“What makes this project stand out is that it was carried out locally, as a team, by people from the plant—dedicated individuals who are proud of what they do,” said Bégin. “As a pulp and paper expert, I’ve been working with Domtar and the Clermont plant for over 15 years. Being involved from the start in such an innovative and complex project, one that affects the plant’s entire heating system, was a truly stimulating experience. The openness, teamwork, information sharing, team availability, and management support that marked this initiative were unquestionably key to its success.”