Hot technology for hot boards: Innovative KSB technology for handling thermal oils

Producing wood-based chipboard is quite a hot process: First, the wood chips are dried in a rotating drum with hot gases at temperatures around 350 °C. After the dry chips have been bound together, they are pressed to form the actual board. This requires temperatures of up to 285 °C.

To be able to use such high temperatures continuously and evenly, thermal oils are used. At Kronospan the oil is heated up using recycled wood, which is burnt in a special wood energy production system. Once the oil is heated, it is transported to the production facility.

In the Kronospan facilities in Menznau, located in the Lucerne hinterland, more than 50 heat transfer fluid pumps made by KSB carry out their responsible task. The heating and control circuits alone are fitted with 40 Etanorm SYA and Etanrom RSY pumps of various sizes. In the main energy centre, which was inaugurated in February 2010, the modern plant is equipped with another six Etanorm SYA and three Etanorm RSY pumps as well as pumps of the new KSB type series Etanorm SYT. Another four Etanorm SYA and Etanorm RSY pumps were installed as part of modification work at the heat energy supply system in the production facilities.

Kronospan Schweiz AG is part of the Swiss Krono Group, a leading company specialised in producing and refining wood-based materials. The company's facilities in Menznau produce particleboard and fibreboard for furniture and interior finishings as well as high-density fibreboard (HDF) for laminate flooring. Since 1969, when the first chipboard left the factory, the company has trusted in KSB pumps for handling thermal oils – a long partnership that is still going strong.

What was special about this project were the tough demands the production process places on the thermal circuit – especially the high temperatures that would be enormously challenging for any pump system. The fluid to be handled was mineral thermal oil of the type Transcal N, which is characterised by a high thermal stability and a good thermal conductivity. Transporting such thermal oils in these temperature ranges requires pumps of extraordinary robustness and maximum operating reliability.

When the heat is on, experts are needed – for example Etanorm SYT with the new VenJet® venting feature. These systems are perfectly prepared for their hot and oily work. KSB’s patent-pending VenJet® venting contour ensures that the gases contained in the fluid handled can be separated and collected in a different chamber. This allows them to be released in a controlled manner via a screw plug. The pumps are especially sturdy in design and remain torsion-resistant, also in hot temperatures. Further benefits of Etanorm are its low heat transfer to the bearing bracket, low maintenance requirements and, as a result, its excellent operating reliability.

The pilot pump is an Etanorm SYT 150-400 with a flow rate of 470 m³/h, a head of 46 m and a remarkable efficiency of 83.8 %. For decades KSB service specialists have been supporting the site with great care to prevent failures and costly downtimes. The proven benefits of Etanorm SYT are more than ready for the future.

The company: Kronospan Schweiz AG

Founded: 1966

Employees: 434 (April 2010)

Production of particleboard: 410,000 m³/year

Production of medium-density fibreboard (MDF): 223,000 m³/year

Engineering contractor: Ness Wärmetechnik GmbH, Remshalden

General planning: Richard Kablitz & Mitthof GmbH, Lauda-Königshofen

KSB type series used: Various Etanorm models, some with VenJet® venting contour

Fluid handled: Thermal oil type Transcal N

Operating temperature: 280 to 290 ºC

Commissioned: February 2011