Borregaard installs first Valmet Inlet PF
Borregaard in Norway is the first to equip its TwinRoll press with the new Inlet PF. The press has now been running for half a year without a single disturbance – and with gentler handling of both fiber and equipment.
Pulp distribution from the previous inlet boxes on the press was uneven across the whole width of the roll under certain process conditions. This meant the roll had to be cleaned during operation, which is difficult depending on the temperature and chemical composition of the pulp. Given the risks of cleaning under these circumstances, an external company with experience of this type of task was hired to complete the job.
Valmet Inlet PF – the new inlet box
Dealing with this problem was a cooperative effort. Valmet, together with Borregaard, developed a new type of inlet box which, by means of a distribution screw, distributes the pulp evenly across the whole width of the roll. In mid-October 2016, during the regular autumn shutdown, installation was carried out on their TwinRoll DPB-935 roller press. The existing inlet boxes and piping were disassembled and saved to reinstall if the Inlet PF did not operate according to plan.
Valmet Inlet PF worked immediately. With help from the new pressure sensors it is now possible to see that pulp is distributed uniformly across the whole width of the roll. What’s more, solids content has increased by about 4%. These factors have led to clearly improved washing efficiency. The press can now be run at lower torque at the desired solids content. And this results in more gentle handling of both fiber and equipment.