THE NEW TMP PLANT
By Pulp & Paper Canada
By Pulp & Paper Canada
Paprican is in the final stages of installing the latest generation thermomechanical pulping (TMP) pilot plant, complete with a screening and cleaning system, at its Pointe-Claire, QC, facility. The T…
Paprican is in the final stages of installing the latest generation thermomechanical pulping (TMP) pilot plant, complete with a screening and cleaning system, at its Pointe-Claire, QC, facility. The TMP pilot plant is supplied by Andritz and consists of a chip bin, impregnation screw that can be used to add chemicals for CMP and CTMP experiments, and a 22-inch single disk refiner. This equipment complements the existing 36-inch diameter Bauer double-disk atmospheric refiner.
Paprican has a strong tradition in mechanical pulping. It stems from Douglas Atack’s work on fundamental mechanisms to Mustafa Stationwala’s films taken inside refiners, from Alkis Karnis’ understanding of the development of fibre properties to Keith Miles’ and Don May’s theoretical work leading to the definition of refining intensity. Mechanical pulping pilot plants have been part of this tradition. The next generation of mechanical pulping facilities will be commissioned in the fall of 2000.
The new screening and cleaning pilot plant in Pointe-Claire mirrors a similar installation in the Vancouver laboratory giving added flexibility to our experimental programs. It builds on Paprican’s expertise in the fundamentals of fractionation, the characterization of screen performance from an engineering perspective, and the modeling and control of screen rooms. The screening and cleaning pilot plant has a Hooper PSV 2100 screen with a wide variety of different screen plates containing holes or slots of varying size. All fluid and feed flows, tank levels and stock temperatures are monitored continuously using advanced data acquisition systems. This allows a single person to operate the process. Under closed loop control the fractionated pulps are recycled back to the feed tanks. This mode is used to calculate reject rates or determine fractionation efficiency. The open loop mode is used to prepare pulp for a paper machine trial or for reject refining by using the Thune press to thicken the fractionated pulp before a subsequent refining stage.
The new TMP and screening pilot plants combined with debarking and chipping equipment make it possible to go from logs to chips to pulp, and finally to paper on the pilot paper machine. This is important because quality will be the key industry driver in the coming years. Paprican has the pilot equipment to optimize unit operations and evaluate pulp and fibre properties from new mechanical pulping processes. Coupled with the pilot paper machine it is also possible to evaluate the paper machine runnability and end-use properties of papers made from these pulps.