1 tonne of steam saved every hour in La Papeterie du Léman

La Papeterie du Léman, a Paper mill located in France, was no exception. But, with the support of Alfa Laval heat transfer solutions, they are now able to save 1 tonne of steam per hour and 12.5 GWh of energy per year.

There are two key products required during the drying process.

• The first is clarified water, composed of water, fibers, and paper debris, that can reach a temperature of 60°C during this manufacturing step. This water is usually left untreated as it will be transported to a wastewater treatment plant.
• The second product is condensates, which bring temperatures to a further 100°C. While effective, the methods used in this step come at a cost, dispersing a large quantity of waste heat into the atmosphere every year.

Seeing the inevitable increase in their energy costs and wanting to take on a more sustainable approach to their business practices, La Papeterie du Léman contacted Alfa Laval to find a solution that could efficiently recover the condensate from their dryer.

The energy projects manager chose Alfa Laval with the aim of using the thermal heat from the condensate to preheat the water in their steam production process, closing the circle within their system. With over a century of experience in heat transfer solutions, Alfa Laval was the perfect match.

Energy savings equivalent to 12.5 GWh/year

The challenge in this project was finding a way to transfer the steam upstream, close to the boiler, despite its high propensity for clogging. But, thanks Alfa Laval heat exchangers, the project was completed successfully and producing results in just a year.

Now that the steam is preheated using the thermal heat from their condensate, La Papeterie du Léman save 1 tonne of steam every hour from the water entering their boilers. In total, that amounts to 12.5 GWh of energy saved each year at the paper mill.

Alfa Laval's customized solution

The Alfa Laval team worked closely with the customer and decided to use 2 Alfa Laval WideGap plate heat exchangers. They would place one at the dryer outlet and the other on where the waste from the machine goes to the sewage treatment plant. These heat exchangers would be strategically located at points that maximize the customers overall efficiency and avoid loss of heat.

These exchangers have proven to be the ideal solution for passing loaded fluids thanks to the optimal spacing between each plate. They are being able to maximize the heat extracted from the condensate without causing the clogging that was anticipated from the paper fibres in the water. But that is not all. The adapted design of these gasketed plate exchangers make maintenance and the possibility of adjusting capacity in the paper mill easy.

Head of the Energy Division of Alfa Laval France, Christophe Leveque comments:

In most industries, there are opportunities to recover all or part of the energy lost in processes. Alfa Laval has a range of solutions that can adapt to all challenges for industrial waste heat recovery. By collaborating with our customers and thanks to the support of our teams, immense savings are possible, which are beneficial for our planet, and for their energy bills. Businesses just need to take the first step.