Biodegradable, renewable and thus seen as much more ecological than their petroleum-based alternatives, starch-based adhesives have been increasingly utilised in the production of paper and cardboard to bond multiple paper layers together.
Starch glue feeding and recirculating is said to be one of the most demanding tasks in these heavy-duty manufacturing processes, with the quality of the glue – which is sensitive to high temperatures and excessive shear forces – being crucial for the achievement of the desired paper/cardboard properties.
To avoid filming, starch-based adhesives need to be pumped smoothly at a consistent, reliable rate with as little pulsation as possible. Diaphragm pumps have traditionally been the pumps of choice for this application which, due to the large pumping volumes required and the nature of the raw material used, entails major energy expenses. With process air generation accounting for a significant portion of paper and cardboard manufacturing plants’ total operating costs, the choice of the right diaphragm pump model can make a huge difference.
Aro’s Evo Series electric diaphragm pumps address the primary pain points of paper and cardboard makers. With their design featuring three process chambers, precise torque control, and high-efficiency electric diaphragms, these pumps are said to offer a stable flowrate with very low pulsation levels and energy savings compared to competitive positive-displacement pump models.
The Evo Series pumps are claimed to be capable of gently handling starch-based glues with a wide range of viscosity levels without the use of an additional pulsation dampener, which prevents any damage to the quality of the adhesive and the finished end product itself. They are self-regulating, adapting to demand variations that are typical for starch glue applications. The pumps promptly react to sudden increases and decreases in flowrate requirements, which obviates the need to change the pump set-up when moving from full production load to recirculating load.
These characteristics, combined with the Evo Series electric diaphragm pumps’s robustness and durability, mean that in many situations, one pump can actually perform the same job as two pumps derived from a different technology.
An unnamed Aro customer said: “Using the Evo Series, you can run only one pump at a time and have another one on stand-by to further optimise the energy consumption of your manufacturing plant without compromising, and often actually increasing its productivity rate.”
