DIAGNOSING DISTURBANCES IN THE WET PART CHEMISTRY OF A PAPER MACHINE

摘要

A procedure and apparatus for locating the pieces of apparatus and/or unit processes causing disturbances in the wet part of a paper machine, said apparatus comprising detectors (1, 2, 3) for detecting consistency, pH and conductivity of the pulp slurry, detectors (4, 5, 6) for detecting the Ca, Al and silicate ion concentrations of the slurry, continuously on line, members (13 to 21) for detecting the periodicity of pieces of apparatus and/or unit processes, and a calculating unit (30) disposed to determine the normal levels of the signals, their normal characteristics and/or the transfer characteristics between signals and to determine the signal deviating from normal and to compare it with the detected periodicities of pieces of apparatus and/or unit processes in the preceding process phase, in order to locate the source causing the disturbance in the quantity in question.