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Stora Enso is piloting MV Titanium™ in Varkaus Mill
PAPER INDUSTRY NEWS
Jino John
10/12/20263 min read
Stora Enso, the renewable materials company, is piloting ABB’s MV Titanium™ technology - the world’s first medium voltage motor with built-in speed control – to operate a primary air blower at its Varkaus Mill in Finland. The new unit has been installed as an upgrade of an existing direct-on-line (DOL) motor and is already delivering energy savings.
Stora Enso, as part of the global bio-economy, is a leading provider of renewable products in packaging, biomaterials, and wooden construction. Varkaus Mill produces around 420000 tonnes of containerboard a year for the manufacture of corrugated boxes, which provide durability and strength in shipping and packaging applications. Stora Enso aims to continuously improve energy efficiency, strives towards energy self-sufficiency, and low carbon solutions at its operations.
In Stora Enso’s quest to improve energy efficiency at Varkaus Mill, one focus area was the primary air blower for the fluidized bed boiler that produces steam and energy for the factory. With the old DOL motor, the output was throttled by a damper. This method of control was inefficient.
“It was clear that installing a speed-controlled motor for the primary air blower was vital to cut our energy consumption. And we already had experience with using ABB variable speed drives (VSDs). The challenge was that we had no space in our electrical room to install another drive, so after we saw the MV Titanium™ concept on the factory floor, we recognized it as the ideal solution. This installation is in its early days of operation. However, it is already providing valuable data, that will help us to further optimize the motor’s setup to deliver additional benefits,” said Tarmo Saukkonen, Production Superintendent, Varkaus Mill, Stora Enso
The power of innovation
MV Titanium™ revolutionizes how electricity is converted into motion. ABB is the first to offer a medium voltage motor where speed control is brought right next to the process. The simplicity of the installation is groundbreaking: a compact motor and speed control solution that doesn’t require an electrical room, separate HVAC systems or an additional transformer. This eliminates the need for long cabling runs, enabling significant installation savings. It is an ideal solution for pumps, fans and compressors.
Fast installation and commissioning
A major benefit of MV Titanium™ is that the whole electromechanical powertrain is designed, factory tested and delivered as one package. This enables a new speed-controlled motor to be brought online on a fast-track basis. The whole process was completed in three weeks in Stora Enso Varkaus Mill.
Contributing to their energy saving goals
The pilot MV Titanium™ unit delivered to Stora Enso is rated at 6.3 kV, 1.25 MW and 1490 rpm. ABB’s advanced engineering capabilities and energy efficiency expertise have proven themselves again in this installation, as data calculated showed potential energy savings over the DOL motor of around 47 percent.
The source of the energy savings is shown in Figure 1, where the gray bars indicate the energy consumption of the throttled DOL motor setup, while the green bars are the lower consumption of the MV Titanium™ speed-controlled setup. The primary air blower was found to run mainly between 40 to 60 percent flow, with the largest saving at the 50 percent mark, where it operates for the majority of the time.
Figure 1 – Energy consumption for the primary air blower powered by the new MV Titanium™ controlled-speed motor
Projected over a year, the MV Titanium™ will cut the energy consumption of the primary air blower from 5300 MWh to 2900 MWh. That is an annual saving of approximately 2500 MWh – enough energy to drive an electric vehicle for 14 million kilometers, or more than 300 times round the world.
Targeting emissions
In addition to boosting productivity, the MV Titanium™ is also helping Stora Enso to reduce CO2 emissions. Based on the figure provided by Fingrid for the CO₂ emission factor for electricity consumed in Finland (including imports) of approximately 26 g CO₂/kWh, then the annual amount of CO2 reduced is around 65 tonnes. That is the same as 18 gasoline powered passenger vehicles driven for a year.
The potential savings will vary in different areas of the world according to the local energy mix and the consequent carbon intensity. For example, in Germany it could be around 822 tonnes of CO2, while in India the figure could be as high as 1,800 tonnes of CO2.
Motor is quieter
The MV Titanium™ is also quieter than the DOL design it has replaced. Its lower noise level contributes to a safer working environment.
For more information on MV Titanium™
