b'DRYER SECTION INNOVATIONSEfficiency in the Dryer SectionPocket ventilation offers great potentialBy Sven Bauchmller, Leader TASK, Heimbach GmbHFigure 1. Unfavourableundercurrent.Whenever energy savings aremachine has been regularly measured1). This meant it flowed past the concerned, the focus is on the dryerand successively optimised bymachine but does not contribute to section. As is well known, nearly 65%Heimbach TASK.the drying process.of total energy demand comes from drying. It is therefore imperative that,LASTING IMPROVEMENT BLOW PIPES SHOWING THE WAYfor example, air inflow and outflowFollowing measurements taken, aConsequently the drying performance are correct in the hooda placestep-by-step restructuring of the dryerwas still not sufficient to be able to where analysis can often highlightsection from conventional to Slalomproduce heavier grades (60 g/m2) at bottlenecks or areas for improvement.was recommended. This was tackledmaximum speed. The solution was the This is one measure among many thatover the following years; first the third,use of blow pipes, which significantly can help papermakers not only savethen the fourth dryer group (groupsimproved drying capacity. Blow pipesThe first costs, but also increase productivityone and two were already runningare built into the cylinder pockets,success which similarly relies heavily on a fine- as a slalom). The first success waswhich often leads to both higherwas much tuned dryer section. The Heimbachmuch improved runability with visiblyproductivity and energy savings perimproved TASK-Force will investigate andfewer sheet breaksand at the sameton of paper at the same timeonerunability focus on pocket ventilation: anyoneproduction speed as before! Thomasmeasure, two benefits. This was alsowith visibly approaching this correctly is likely toFischer, Leader of TASK summarises:the outcome with customer, though offewer sheet reap considerable rewards!More productivity, more quality,course all the optimisations should bebreaksand more efficiency. However, this wasconsidered as a whole in this case. Inat the same The first case study is a customernot the end of the optimisation plantotal, the Slalom conversions and blowproduction producing newsprint (40-60 g/m2)as the air inflow was still directed intopipe installations took place over a tenspeed as at 1,000 m/min. For a long time, thethe basement as undercurrent (Fig.year period. before!34 WORLD PULP&PAPER'