Yueyang Forest & Paper’s papermaking line PM 11: World record start-up through great cooperation

From the very beginning, the 11.15-meter-wide paper machine PM 11 has performed well, achieving a series of impressive accomplishments. The machine started up in December 2024, 80 days ahead of schedule, reaching one of the best start-up curves so far. According to Liu Lixin, General Manager, Yueyang Forest & Paper, there has not been a single major injury since PM 11’s start-up, which reflects the excellent equipment safety and provides a strong foundation for Yueyang Forest & Paper’s production.

Yueyang Forest & Paper’s management and project team with Valmet’s team celebrating PM 11’s exceptional start-up curve achieving 1,700 m/min in 80 days.

Long partnership a basis for successful cooperation 

The successful cooperation between Yueyang Forest & Paper and Valmet during PM 11’s start-up comes as no surprise: Their collaboration started decades ago. The partnership has continued to be strong in this project as well. “The cooperation was very successful! From project negotiation to start-up and production optimization, the entire process exceeded expectations, and the goals of each stage of the project were successfully achieved,” says He Ganghui, Project Consultant at PM 11, Yueyang Forest & Paper.

Liu Lixin, General Manager of Yueyang Forest & Paper, giving a speech at the plaque ceremony.

Choosing a well-established technology supplier can also help a papermaker stand out in the industry and maintain technological leadership. “The key is to establish deep cooperation with high-end technology suppliers like Valmet. We can thus obtain cutting-edge technology, improve the automation and intelligence level of the equipment, and maintain a leading position in the fierce market competition,” explains Zhu Hongwei, Chief Engineer, Yueyang Forest & Paper.

The cooperation between Yueyang Forest & Paper’s and Valmet’s experts was close at every step of the project.

With active participation throughout the project, both Valmet’s local project team and global experts were able to help Yueyang Forest & Paper solve all the challenges ahead efficiently. “Valmet’s technical team had a comprehensive understanding of the project and technology, and precise control of the details,” explains Zhou Shenshu, Mill Manager at PM 11, Yueyang Forest & Paper.

Complete stock preparation line boosts efficiency and quality

PM 11 has a complete stock preparation line and approach flow system from Valmet, including a Valmet cleaner plant equipped with Valmet Twister Hydrocyclone and Valmet Hydrocyclone Cleanpac 700MCD cleaners, Valmet Disc Filter, and Valmet Conical Refiner Conflo units. A stock preparation line has enhanced the paper machine’s performance and operability, delivering both superior efficiency and product quality.

“When we chose the stock preparation line, we definitely considered the entire production line’s overall efficiency. A single supplier has a better understanding of their own equipment, and this can lead to better quality and operational efficiency, Chen Liqun, Process Manager at PM 11 explains.

Ten Valmet Conical Refiner Conflo units are used for the fiber treatment of bleached softwood kraft pulp (NBKP), bleached hardwood kraft pulp (LBKP), and mechanical pulp. The low-consistency refiners have performed strongly, contributing significantly to improved pulp quality and refining efficiency. Compared to earlier refiners, Valmet Conical Refiner Conflo units offer better overall efficiency, enhance fiber treatment, and increase the refining rate. The system has also enabled a substantial reduction in freeness levels from the original design value of approximately 300 to around 230, improving end-product quality even further.

“In terms of the entire stock preparation process, I believe that Valmet’s system is truly something to be proud of. Time has proven that Valmet’s refiners are world class in terms of energy consumption, performance, maintainability for our maintenance personnel, and operational reliability,” says Wang Jie, Senior Manager at PM 11.

Wet-end technologies for high-quality paper production

PM 11’s wet end includes an OptiFlo Gap headbox and OptiFormer Gap forming section with shoe and blade technology that contribute to the machine’s energy efficiency and help ensure the uniform quality of the paper. The new forming section has been especially important for the machine’s energy efficiency. “OptiFormer Gap forming technology can accommodate good formation levels with higher headbox consistency, which means significant pumping energy savings,” explains Zhu Hongwei. 

PM 11’s wet end includes an OptiFlo Gap headbox and OptiFormer Gap forming section with shoe and blade technology.

PM 11’s press section includes a new OptiPress Linear press. According to Zhou Shenshu, the optimized shoe nip lengths and high linear loads used in the press section result in high dewatering. Moreover, the dryness after the press section has reached 54 percent without significant bulk loss. “The press section brings flexibility to paper production, adapting to various production needs. Maintenance is simple, operation is easy, and safety isn’t compromised,” explains Wang Jie.

Improved efficiency with drying and finishing technologies 

The OptiRun Hybrid dryer section is equipped with Hirun Runnability System, ensuring high drying efficiency and effectively reducing paper breaks. “Thanks to the advanced Hirun runnability components, increased Vac Roll suction hole diameter, and the Vac Roll’s design with arc-shaped grooves, there are no issues with paper lint clogging. Downtime has also been reduced significantly,” says Wang Jie. Maintenance of the dryer section and changing the dryer fabric are safe and practical. “Currently, with movable equipment, changing a dryer fabric is fast and takes only 1.5 to two hours,” Wang Jie adds.

OptiCalender Hard enhances the paper’s smoothness and ensures its surface properties.

To ensure the paper’s smoothness and surface properties, Yueyang Forest & Paper invested in OptiCalender Hard calendering technology. “The application of hard nip calendering technology enhances paper smoothness while ensuring bulk stability,” says Zhu Hongwei. “Operating at loads of 40–50 kN/m and a temperature of 120 °C, the calender achieves paper Bekk smoothness over 40 seconds and a bulk of 1.28 cm³/g,” explains Chen Liqun.

PM 11’s winding capacity was ensured with two state-of-the-art OptiWin Drum two-drum winders which have fulfilled the safety and quality requirements of Yueyang Forest & Paper. “Operation is easy, the set change time is short, running is very smooth, and the quality of the rolls is excellent. The improvement in tail threading speed and the reduction in the workload of winder operators further optimize production efficiency,” Wang Jie underlines.

  Two OptiWin Drum two-drum winders ensure PM 11’s winding capacity.   

Scope of supply

Valmet’s delivery for the papermaking line PM 11 consisted of a complete stock preparation line and approach flow system, including Valmet cleaner plant equipped with Valmet Twister Hydrocyclone and Valmet Hydrocyclone Cleanpac 700MCD cleaners, Valmet Disc Filter and Valmet Conical Refiner Conflo units, an OptiFlo Gap headbox, an OptiFormer Gap forming section with shoe blade technology, an OptiPress Linear press section, OptiRun Hybrid dryer section with Valmet Hirun System, an OptiSizer Film size press and supply system for the sizer, an OptiCalender Hard calender, an OptiReel Center reel, process ventilation systems – including an OptiAir Hood high-humidity hood and OptiAir Recovery heat recovery – an OptiCart Stream parent roll cart and horizontal transfer rails, and two new OptiWin Drum two-drum winders.

The supplied process technology was supported with services and automation systems with industrial internet solutions.

Text: Veera Silakoski, Miia Kaisanlahti