Verifiable benefits

CASCADE recirculates part of the process steam produced during drying in cylinder dryers, enabling genuine, efficient energy recycling within the machine. Specific data on the recycling volumes achievable in practice was gathered in tests carried out at Getzner Textil in Bludenz. The tests looked at a drying line with ten cylinders during one shift and the production of seven weaving beams.

Steam System

The last four cylinders of the systems had been operating with a mixture of recycled flash steam from the first six cylinders and live steam. The respective supply quantities of recycled steam were measured. The results prove CASCADE’s effectiveness. At full machine load, 51 kg/h of the total 1,295 kg/h of steam required was obtained directly through the inline recycling of the CASCADE system.

As plant utilization declined, the potential savings in fresh steam decreased, but even at low-capacity utilization, reduction effects were evident. These are also influenced by the recipe, i.e., the process conditions. The following applies: the greater the temperature difference between the first and second cylinder sections, the greater CASCADE’s efficiency.

CASCADE thus opens up potential that can always be exploited without restrictions on the recipe. However, the magnitude of this potential can be influenced – unlike, for example, the eco mode in a car, which reduces performance and acceleration once activated.

Significant savings potential

(Left to Right) Thomas Rossi, Karl Heinz Vaassen and Werner Egger

The lower live steam consumption enables cost savings and a reduced carbon footprint. At full machine and production utilization – three-shift operation, 5,000 hours/year, 83% efficiency – and a steam price of €40/t, a cost reduction of around €8,500/year can be achieved under the representative practical conditions at Getzner Textil. In addition, in this specific example, it was possible to reduce the company’s environmental impact by 59 tons of CO2e/year.

Given the common practice of feeding condensate that is usually too hot for use in the boiler house back into the operating network, thereby losing thermal energy, every contribution from CASCADE pays off. For all customers who operate the feed water tank in the boiler house without pressure, any excess energy above a condensate temperature of 100°C is lost when it is fed back into the company’s own media network. The white steam clouds rising from the boiler house are a visible sign of this. With CASCADE, operators can minimize this loss of power without additional investments in machine peripherals.