Valmet's new aqua cooling calendering technology has been taken into use first time at customer site at Stora Enso Ingerois Board Mill in Finland. Stora Enso decided to modernize the precalender of its board machine BM 4 to improve the quality of the produced board and lighten the board - i.e. increase its bulk - without compromising its properties. BM 4 produces folding boxboard for the consumer packaging industry.
The new aqua cooling technology has now been successfully used in production for a few months. The technology has made it possible to lower the basis weight of the end product at BM 4 while maintaining the functional and visual properties of the board.
"The new aqua cooling technology enables developing and optimizing the machine's operating method to achieve bulk saving potential. This brings significant energy and raw material savings throughout the value chain of the product," says Taisto Nevalainen, Mill Director of Stora Enso's Ingerois Board Mill.
"Cooperation with Stora Enso was excellent from the very first contact to the start-up and the whole process was exceptionally fast. Using the new aqua cooling equipment in practice has confirmed the earlier results from our pilot machine. Installation of the equipment itself went well, and thanks to its compact structure, the equipment fits in perfectly despite the narrow space available," says Mika Viljanmaa, development manager from Valmet's Paper Mills Business Unit.
Valmet focuses in its research and development work on three areas: 1) ensuring advanced and competitive technologies and services, 2) enhancing raw material, water and energy efficiency, and 3) promoting renewable materials. The now introduced aqua cooling technology focuses especially on improving the material and energy efficiency in paper and board making process.
The idea of aqua cooling is that the paper web is cooled down by evaporating moisture from the web. The effect can be enhanced by adding a small amount of water on the web surface before cooling. The cooler the web is before it reaches the calender, the more quality improvement and raw material savings can be obtained.