The Secret Behind Energizing Pulp and Paper Evaporators: Ultrasound

Fouling in evaporator tubes is a time and energy consuming problem for the pulp and paper industry. It not only leads to higher costs and risks but also increases emissions and wastage. Find out how Altum’s ultrasound technology can change this and improve energy efficiency in an evaporator

The International Energy Agency (IEA) estimates that the pulp and paper sector needs to limit its energy use growth to 0.5% per year to align with the Net Zero Emissions by 2050 scenario. The sector’s overall energy use has been declining for a decade, but it continues to be among the top industrial energy consumers. This is why there is still great potential to make a significant difference.

Bioenergy and alternative fuels based on paper by-products like black liquor are used increasingly. They already account for 40% of the total energy use, but that is not nearly enough. This is where energy efficiency comes in.

Energy efficiency cuts down

– production losses
– production downtime
– water usage
– effluent waste and
– people and process related risks.

Energy efficiency thereby leads to lesser emissions. So how can pulp and paper companies be more energy efficient?


Making the Switch

Research suggests that rising costs coupled with energy shortage is already a good business case for the pulp and paper industry to invest more in energy efficiency.

IEA points out that efficient equipment operations and maintenance are vital in raising energy efficiency, which is a crucial strategy to decarbonize the sector. No doubt, Ultrasonic technology can play a big role in that.

Altum’s software-guided Zero Process Downtime (ZPD) ultrasound cleaning is a sustainable and cost-efficient way for pulp and paper mills to be more energy efficient and reduce their environmental impact.  Ultrasound is chemical-free and can increase energy savings in evaporators by more than 50% and increase their uptime by 25% even as it controls erosion and corrosion.

In comparison, traditional methods of cleaning fouling are costly as they involve the use of chemicals and mechanical washing procedures, which are only possible with significant production downtime.


Demonstrated Results in Pulp and Paper

For instance, Finland’s Pulp and Board Mill uses steam to evaporate water from black liquor from 10% to over 50%. But as the temperature rises, dry material content and the viscosity of the black liquor increase as well, resulting in calcium-based fouling issues across the company’s production line of seven tubular evaporators.

Two of the company’s hottest evaporators had clogged tubes. Altum’s externally attached solution focused a high-power ultrasonic field on the black liquor flowing in the pipes of the evaporators. It affected the crystal structure of calcium-based fouling to avoid it from attaching itself to the tubular structure of the evaporators. This process reduced the need for mechanical cleaning by 70% and increased pumping efficiency by more than 10%.

ZPD works both on black liquor evaporators and red liquor evaporators. A case in point is South Africa-based Pulp Mill. Altum’s ZPD helped raise the energy efficiency of its evaporators by more than 50%, the evaporation rate by more than 6%, and the operational time by 25%.  In addition, the period between washes of evaporators increased by 60%.  That’s the power of Altum’s highly focused ZPD technology.

What challenges are you facing with evaporators? We are here to help – contact us now.