Smurfit Westrock, a world-leading manufacturer of paper-based packaging, has committed to reducing CO2 emissions by 55 percent before 2030. At the company’s flagship Roermond paper mill in the Netherlands, innovation and continuous improvement measures support the progress toward that goal and beyond.
“The best projects for us are the ones where we can actually lower our energy consumption – says Wouter Lap, Managing Director at Smurfit Westrock Roermond Papier. This is one reason why the PM 1 at the Roermond paper mill became the first-ever paper machine to install the groundbreaking HighPerformance Press solution from Voith and with resounding success. After installing HighPerformance Press, we have seen a higher dry content after the press section and lower steam consumption, which helps us reduce our carbon emissions – explains Lap. But the advantages don’t end there for the PM 1, which has an operating speed of 1,250 m/min, a sheet width of 5,000 mm and an annual production capacity of 275,000 tons of highperformance lightweight packaging paper with basis weights between 80 and 135 g/m². This solution also has a cost-price benefit – Lap adds – and it has increased our machine capacity”.
This full range of customer benefits is exactly what Richard Horn, Global Product Manager Press Section at Voith, was aiming for when an interdisciplinary team of Voith experts first set about improving the energyefficiency and performance of the already world-beating NipcoFlex shoe press technology. As mechanical dewatering is a much more energyefficient process compared to thermal drying, enhancing the process would reap greater benefits for customers, particularly as mechanical dewatering can be powered solely by electricity, unlike conventional thermal drying systems which still mostly rely on fossil fuels.
“With our HighPerformance Press we have optimized all relevant shoe press components to make papermaking more effective and sustainable – explains Horn. For Roermond, HighPerformance Press achieved a 1 percent increase in dry content, which translates into a 4 percent reduction in steam consumption in the dryer section. A higher dry content improves machine runability – adds Horn. Customers can also choose to take advantage of the higher dry content to speed up the paper machine by 4 percent, which allows an increase in production capacity”.
Customized modifications, maximum results
The pilot installation on the Roermond PM 1 was the final step in the intensive development process for the innovative solution. It followed tomographic scans, advanced computer and flow simulations, laboratory experiments, working prototypes and pilot machine trials at the Voith Technology Center, the company’s innovation hub in Heidenheim.
The whole process drew extensively on the full-line supplier expertise of Voith engineers and research and development (R&D) centers. As a result, HighPerformance Press is a finely tuned combination of modifications to the NipcoFlex shoe press and customized Voith press fabrics and QualiFlex press sleeves that work seamlessly together to achieve the desired pressure gradient for optimized mechanical dewatering.
The choice of press fabrics is crucial to success as their dynamic properties impact the compression performance. Simulations show that, depending on the initial conditions, up to a 3 percent increase in dry content can be achieved, which reduces the steam consumption by up to 12 percent. Most notably, the new solution is easily tailored to the specific conditions of any paper machine and is quick to install.
At the Roermond paper mill, the upgrade took under 40 hours and maximized mechanical dewatering functions immediately after start-up.
“HighPerformance Press is a relatively easy modification with an interesting payback – Lap confirms. It’s another valuable step in decarbonizing our heat needs and achieving challenging sustainability goals”.
Mastering performance at the headbox
“The MasterJet 4Tec is another big step forward in paper machine technology – highlights Markus Häussler, Product Manager for Headboxes at Voith Paper. After hundreds of successful installations of the MasterJet Pro, it’s time for a new headbox generation to take over”.
The number four in the name has special significance. It stands for the fourth generation of MasterJet headboxes, following on from MasterJet, MasterJet II and MasterJet Pro. It also features four innovative improvements – covering formation, pulsation damping, ease of operation and energy efficiency – that set the MasterJet 4Tec apart.
Next-level functions and operation
“For many paper grades, sheet formation is a key quality parameter and the headbox has a considerable impact on it – explains Häussler. We are therefore very proud that we made a big step forward with the MasterJet 4Tec. A combination of a newly designed turbulence tube and a new lamella concept ensures that the homogeneity of the headbox jet has reached a new level”.
Compared to the already very good performance of the MasterJet Pro, the MasterJet 4Tec provides up to 50 percent improvement of fiber distribution and streak elimination in the jet. This is an excellent basis for best formation levels and avoidance of any streakiness in paper. Today’s new paper machines do not require pulsation damping anymore as approach flow screens and pumps provide very low pulsation levels in stock suspension that are uncritical for sheet quality.
However, there are cases when pulsation damping is still necessary. For instance, when existing approach flow components are reused during headbox replacements, when production capacity is increased or when the flow components are in poor mechanical condition and show higher pulsation levels.
For such applications, Voith has developed a new pulsation damper for the MasterJet 4Tec that offers, no surprise, four considerable advantages. First, it features a flexible membrane that separates the air volume and stock suspension, which eliminates deposits on the tank wall. This is crucial as such deposits can come off and end up in the headbox, increasing the risk of holes in the paper sheet or even production loss due to sheet breaks.
Second, as there is no diffusor plate installed, this damper creates no pressure loss, which reduces energy consumption of the headbox fan pump. Third, it does not need any cleaning showers, so there is no fresh water consumption. And fourth, it is also more compact and easier to install, even on existing machines. In addition, the MasterJet 4Tec ensures simple operation and clean surfaces around the headbox, which are two key topics of interest for any papermaker.
“We have received a lot of positive feedback from our customers regarding our current MasterJet Pro headboxes, but still we wanted to make further improvements – says Häussler. We therefore focused our attention on these two topics during the whole development process.”
One key innovation is the new EdgeMaster, which prevents the stock suspension from bleeding at the sides. The latest generation has the same innovative features as the EdgeDeckle-S, including a new Teflon sealing concept, easy-to-adjust S-shape zones and an intuitive design.
Now, it’s no longer necessary to remove the EdgeMaster when the wire is changed. The EdgeMaster is simply swiveled upwards, and, after the wire change, it is returned to the same position and no further adjustment is needed. “The new design ensures a clean wire edge and easier operation – adds Häussler. And it is effective in the elimination of the edge wave effect”.
Four energy-efficiency levers and a great design
“Typically, energy consumption is not a focus topic for headboxes, but this is not right – says Häussler. The fan pump contributes significantly to the electrical energy consumption of a paper machine, and its energy consumption depends a lot on the headbox. This is why we have put a high priority on reducing the energy consumption of the MasterJet 4Tec”.
The new MasterJet 4Tec uses four levers to reduce energy consumption, which build on proven MasterJet technology. One design feature of the MasterJet Pro has been further developed, namely the absence of a recirculation header. Eliminating the recirculation header leads to a 10 percent reduced flow volume to the headbox.
On top, as mentioned above, the new pulsation damper reduces pressure loss. The new turbulence tube not only improves formation, but it also allows a lower flow speed at specific flows and reduces pressure loss by 0.1 bar. Finally, the new turbulence tube allows a new layout for the turbulence generator. The reduction of pressure loss across the MasterJet 4Tec reduces overall energy consumption.
For example, in one pilot trial with a MasterJet 4Tec, the four levers realized overall annual savings of €103,000 in energy consumption. Further pilot installations are underway that are showing similar results. On top of all the functional improvements and energy-efficient features, Voith also incorporated industrial design principles into the innovation process.
“From the beginning it was clear that just looking nice would be not enough – says Häussler. Industrial design needed to be fully integrated in the headbox development work so that we could identify a solution that combines appealing visual appearance with high functionality and value for our customers, adds Häussler. The excellent result is proof that it was worth the extra effort”.
Torna indietro
