Valmet Steam Separator PV saves energy at BHW Beeskow, case study

In January 2015, Valmet’s first mechanical steam separator for fiberboard production, Valmet Steam Separator PV, was installed at BHW Beeskow Holzwerkstoffe GmbH, Germany. Valmet Steam Separator PVis specially designed for positioning in the blow line after the Defibrator.

Valmet has extensive experience with mechanical steam separators used in the mechanical pulping process. This experience played a key role during construction of the new mechanical steam separator for BHW Beeskow.

What is a mechanical steam separator?

During the defibration process in fiberboard production, a large amount of steam is generated from the moisture present in the chips when they are broken down and the fibers exposed. The mechanical steam separator can divert up to 50% of the generated steam from the fiber flow for recycling in the presteaming bin. This steam replaces a corresponding amount of fresh steam - making great savings possible.

Valmet Steam Separator PV mechanical steam separator

How does it work?

Valmet Steam Separator PV separates the steam from the fiber to allow recovered steam from the blow line to be used for presteaming or in other applications where low pressure steam is required. The separator works on the principle that fibers will be separated from steam if sufficient centrifugal force is imposed on the fibers. To accomplish this the design incorporates a rotor with radial blades designed so that the fibers and steam must accelerate to the same rotation speed as the rotor to reach the exhaust opening. This ensures maximum separation at various production levels without any fiber buildups.

Great savings in energy

At BHW Beeskow, the Valmet Steam Separator PV mechanical steam separator recycles 4-5 tonnes (about 6 bar) steam per hour. The mill has its own facility for producing steam for a turbine producing electricity. The reduced amount of steam the presteaming bin requires is now passed to the steam turbine. Today about 1.4 MW/h more electricity is produced in the steam turbine. This electricity can be sold to the grid as green electricity at a favorable price.

Optimization continues...

After the installation of Valmet Steam Separator PV, the mill's emission levels, quality of the final product and resin consumption remained unchanged. An additional benefit that was immediately seen is the inlet temperature in the dryer. It was reduced by 5-8 ºC. If the dryer becomes a bottleneck, this temperature drop may enable an increase in the production. The BHW Beeskow production manager looks forward to continued optimization during winter months.

For more information on improving improving your mechanical pulping process, contact your Valmet representative.