Cardboard

Investing in quality

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Located near the White Sea, Arkhangelsk Pulp and Paper Mill (APPM) is the largest producer of cardboard in Russia, as well as a key player in bleached market pulp. Creativity compliments major rebuilds at Appm, adding 30% capacity with little investment

Located near the White Sea, about 1000 kilometers northeast of St. Petersburg, Arkhangelsk Pulp and Paper Mill (APPM) is one of the largest producers of containerboard in the country. They produce over 500 000 TPY of fluting and kraft linerboard and have a total mill capacity of over 900,000 TPY, including bleached market pulp. An important player in the European market, their containerboard is considered a benchmark for quality, having a “noble” brown color, reaching over 60 countries. Their domestic market share has risen along with export markets in Italy, Spain and Turkey being strong as well.

Over the past several years, they have invested over EUR 100 million on both board machines, improving quality and reducing environmental impact. BM2’s rebuild for linerboard and corrugating medium started up in 2016, including a new wet end, improvements to the drying section, a new pope reel, slitter, and wrapping and handling system. A new control system was also put in place. Earlier, in 2014, BM1 underwent a comprehensive rebuild, including a new wire section for kraftliner production. From 2014-2016 refining and stock preparation were completely updated. Within the framework of each of these projects, all guarantees for end products were met. Environmental goals from 2013 to 2021 include water consumption cut in half, pollutant emissions down by 65%, discharge water reduced by 75% and greenhouse gas emissions lowered by 18,000 tons of CO2 equivalent.

Alongside the significant containerboard investment, the mill is always in search of ways to improve quality and increase capacity with little money spent. Dmitry Khrapach, board production manager, challenged his team to wonder: what if the bottleneck in BM1 screening could be overcome to open the way for higher productivity.

Focus on thick stock screening for the bottom ply

Says Khrapach, «We need strategic flexibility because packaging is always changing. Fiber yield and optimization is a must. Easy changes from one grade to another have to be smooth. Product appearance must be consistent. Yet, sometimes we had flakes and shives in the pulp causing problems on BM1. Quality problems, too».

«As a result of comprehensive measures performed on the machine, we increased the production rate above design capacity. However, this caused limitations in thick stock screening capacity. So, we needed to increase the screening capacity, which was accomplished without big capital investments. For this purpose we chose AFT, knowing that they have the knowledge and experience in tackling such tasks».

AFT’s Roman Smorgunov, Jussi Karppinen and Tarmo Karioja helped APPM with modelling BM1’s bottom-ply thick stock screening  and mapping out flow changes inside the screens. A SimAudit™ mass and flow balance analysis revealed that major productivity and quality gains were possible. The screen room was limited by inefficient rotors and insufficient open area in the cylinders.

AFT recommended changing over to new high efficiency GHC2™ rotors and cylinders with optimized open area and profile in all three stages to improve pulp throughput, while not sacrificing the accept pulp quality. All three stages employ MacroFlow™ cylinders and high efficiency GHC2™ rotors.

APPM went with the recommendations and also made necessary engineering modifications to the BM1 thick stock screening system, including pumps, pipes, valves. The project was completed in 2018 with all expectations met.

Says Khrapach, “Who says screening is boring? Sometimes you win big by being creative. Simple, bold moves inside our screens improved flow to allow us to maximize output and quality. We achieved a 30% gain in screening capacity, and stable properties of the end product – that’s a big win!”

Intelligence inside existing screens

Roman Smorgunov, sales manager at AFT, points out that the new rotors achieve lower reject thickening than the OEM rotor, meaning that rejects are reduced despite similar reject flows. APPM still closely monitors for fluctuating consistency, but can do so calmly, even during peak production of the board machine.

Khrapach says «Since making the changes, the screens have run smoothly for over a year, so far. Operators and the maintenance team can focus on other jobs».

Khrapach continues «Our discussions with AFT applications experts are always productive because of the way we brainstorm ideas. The best results are reached through creative problem solving and cooperation. We know our mill well and AFT has an in-depth understanding of pulp and paper processes».

Maximizing fiber for market pulp

Producing over 1,000 t/day of pulp, including ECF (Elemental Chlorine Free) since 2019, they cook, screen, wash and bleach birch and aspen for their own machines and produce bleached market pulp for customers. When they bleach, they use hydrogen peroxide as a bleaching agent, replacing sodium hypochlorite.

According to Vadim Moseev, head of APPM pulp production, their ecologically pure product allows for greener, safer pulp production and end products. He considers this to be a competitive advantage of Arkhangelsk APPM on both the Russian and world market. Of note, however, he believes that market pulp requirements demand constant attention to even the smallest issues in the process.

Recently, Moseev and his team decided to reduce fiber deposits on evaporation equipment and increase fiber recovery.

Moseev remarks «Small problems can become big problems, so we address them early. We decided to repurpose an old screen to handle all black liquor flow for our hardwood and softwood Kraft production, which runs at 80-110°C. The goal of the conversion was to recover more fiber from the black liquor stream and meet capacity objectives. We looked to AFT to make this happen».

According to Tarmo Karioja, AFT project manager, who provided technical support for the project, «With our Russian team, we reconfigured the inside of the screen and how the unit was controlled. The upgrade included an AFT GHCb rotor and Electrobeam drilled cylinder along with preliminary layout, piping and process engineering. In addition, new control valves and operating logic were built around the old Hooper pressure screen and existing DCS system».

All objectives for this screen conversion project were achieved, including:

  • reduction of fiber deposits on the evaporation equipment
  • Increased fiber recovery and returning the fiber to the pulp output
  • Running the system in a hermetic environment, without any emissions
  • Running a single screen to handle all of the mill’s black liquor flow

Continues Moseev «Because AFT has been a partner for a long time, our pulp mill has gained many advantages from their know-how, especially around cylinders for screening. Their knowledge is valued by our team as an extension of us».

Back to the point about problems, Moseev quips, «When unsolved problems and little issues are accumulated, it gets messy. I will say it another way… there are no “little issues” in our business. All the issues that arise in the course of our business require a prompt response».

What’s next at APPM?

«Looking ahead, optimization could include replacing screens for paper production – Says Khrapach – «With our productivity gains helping pay for next steps, we are always looking for new ways to meet market needs as they change».

«Every production site is a living organism. There are always never-ending challenges. That’s why we count on the AFT people to discuss problems, and help us solve them. Our recent advances make it possible to figure out the next steps».

According to Risto Weckroth, general manager with AFT, «APPM has become a star in packaging in Russia. They are part of an increasingly dynamic and exciting marketplace. We plan to support their growth with innovation, especially with existing equipment that can reach a higher level of performance».

 

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