UPM-Biofore-Magazine-1-2016-ENG

Mika Hohti, Aki Korpela

Supervisor Mika Hohti monitors chlorine dioxide consumption. Bleacher Aki Korpela is on the right.

which look like large baking ovens. The difference between bleached and unbleached pulp is obvious from the two warm, wet, odourless samples we are handed from the birch line: one is brown and the other bright white. In addition to the modernisation of the fibre line, the third significant improvement made at the plant concerns energy efficiency, as explained by operations manager Matti Tikka at the chemical recovery plant. “Our energy utilisation is more efficient, and we are producing higher volumes of heat and energy. The mill’s self-sufficiency rate in terms of energy production has increased to more than 85%,” Tikka says. More heat is generated because more black liquor is combusted in the recovery boiler. The excess heat is sold to the district heating network. The heat and the ‘green electricity’ produced from renewable rawmaterials support the Group’s sustainability-based business. There is only one final place to visit: the drying machine. We walk another short distance in the clear autumn air to reach the most expensive investment, which is located on the paper mill side, on the site where paper machine no. 7 used to be before it was dismantled years ago. Efficient drying machine This time we enter a control room that is chock-full of bustling people. We watch the monitors and see how the pulp sheets move along the packaging line towards

robot claws. Bales ready for export are neatly packaged with wrapping and wire. Those without wrapping will be transported within Finland. There was a clear need for a new drying machine, as the old one was already more than 50 years old and is currently being dismantled. “The pulp mill can now operate at full capacity even if the paper mill is at a standstill. Production had to be slowed down before, but nowwe are able to even out the consumption,” explains operating engineer Jukka Flinkman . There are other benefits too: the current machine efficiently cools down the pulp web, which reduces the yellowing tendency of the pulp, which canmar the brightness of the end result. The bales also look more attractive now, which is important to customers. Our tour is nearing its end. We pass from the control room to the warehouse fromwhere the pulp is sent to end customers to be processed further. As steam rises from the water in the wastewater treatment plant, forklifts scurry about and trucks with licence plates from several countries are being loaded with brilliant white pulp bales. A train carriage has just been loaded: most of the pulp travels to customers by train. The autumn day draws to an end. The evening shift takes over from the morning shift. The pulp bubbles away, and the paper machines roar. All is well at the Kymi integratedmill site.

Matti Tikka

Energy efficiency has improved considerably. The mill self-generates higher volumes of heat and electricity, says Matti Tikka at the chemical recovery plant.

Hohti lists some of the improvements that have been achieved thanks to the modernisation of the softwood fibre line. “We replaced the old atmospheric diffuser in the brown pulp scrubber with a DD scrubber. As a result, pulp-scrubbing quality, runnability and capacity have improved.” Another improvement is that branches are efficiently sorted and separated, which reduces the amount of rejects and impurities and improves output. What this means in plain English is that the mill gets more high- quality pulp from a smaller amount of wood. Bleacher Aki Korpela explains the secrets of pulpmanufacture in metaphoric terms: “We make rice pudding out of barley porridge,” he jokes laconically. In essence, he’s right: when youmake pulp, you remove the brown colour, or lignin. The final result is a white, porous substance that you can scrape out of the scrubbers,

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