“Andritz helps its customers achieve their sustainability goals by reducing their carbon footprint, increasing water efficiency and minimizing the use of raw materials. There is enormous potential in utilizing secondary heat in different process areas of a pulp mill. When the necessary technology is installed in the mill, heat can be recovered and transferred from one process area to another. At the same time, the carbon footprint is reduced and significant savings in energy and raw water use are enabled,” says Andritzin. Jussi Piira, Director, Sustainable solutions.
Andritz has adopted a holistic approach, developing solutions that go beyond traditional process boundaries. The goal is to find new opportunities to utilize the generated secondary heat in other processes in different process areas of the plant.
“It can be challenging to understand the perspective that goes beyond process areas, as it is easy to focus on just one specific area. However, if we look at the issue from the perspective of the entire plant, a picture opens up of the possibilities for utilizing secondary heat between different process areas,” says Andritzin. Paavo Tolonen, Vice President, Global Product Manager, Cooking.
"The idea is to install reasonably small devices in the so-called 'receiving' processes of the factory. This equipment converts secondary heat into clean steam, which eliminates the need to use valuable steam generated in the recovery boiler, but rather brings the heat from the process 'supplying' the secondary heat," Tolonen explains.
Heat recovery offers many benefits, including energy savings, clean condensate recovery, and optimal utilization of water and secondary condensate. Secondary heat can also be recovered from wastewater and other sources.
“This approach offers not only environmental benefits but also economic benefits. Cost benefits arise when we return the primary condensate to the recovery boiler and we do not have to make boiler water from raw water,” he says. Aki Muhli, Technology Manager, Cooking, Andritz.
“This helps save energy, raw water and demineralization costs, resulting in significant cost savings. Furthermore, maximizing raw water utilization is even more important given the recent record temperatures and droughts across Europe and the world.”
Andritz believes that optimizing and maximizing the use of secondary heat is already fully possible in all pulp mills, as customers have already seen the benefits of the installed technologies.
“Whether it is a new production facility under construction or an already operating mill, utilizing secondary heat from pulp mills offers an excellent opportunity to further promote the circular economy within the mill while achieving significant cost savings,” says Aki Muhli.
What? There is enormous potential in utilizing secondary heat in various process areas of a pulp mill.
Why? As environmental regulations become stricter and pulp producers strive for sustainability goals, it makes sense to utilize all opportunities for secondary heat reuse in the mill.
