Method and apparatus for chromatic control of pulping process
Abstract
Abstract A METHOD AND APPARATUS FOR GENERATING A CONTROL SIGNAL BY CARRYING OUT A CHLORINATION REACTION ON A SAMPLE OF PULP SLURRY AT AN ELEVATED TEMPERATURE FOR A RELATIVELY SHORT PERIOD OF TIME AND MEASURING THE DIFFERENCE IN REFLECTANCE AT TWO PREDETERMINED WAVEBANDS. IN ONE EMBODIMENT THE PULP SAMPLE IS TAKEN FROM A PULP DIGESTER AND THE CONTROL SIGNAL IS REPRESENTATIVE OF THE COOKING DEGREE OF THE PULP, AS MEASURED BY THE KAPPA NO., CHLORINE NO. OR PERMANGANATE NO. THE CONTROL SIGNAL IS ELECTRONICALLY FED TO THE INPUT OF A DEVICE FOR AUTOMATICALLY CONTROLLING THE OPERATIONS OF THE DIGESTER TO MAINTAIN A DESIRED COOKING DEGREE. IN ANOTHER EMBODIMENT THE SAMPLE IS TAKEN IMMEDIATELY AFTER THE ADDITION OF CHLORINE IN THE CHLORINATION STAGE AND THE CONTROL SIGNAL IS ELECTRONICALLY USED TO AUTOMATICALLY VARY THE LEVEL OF CHLORINE APPLIED TO THE CHLORINATION STAGE.
Inventors
- 👤 J Histed
- 👤 W Lawford
- 👤 D Catford
- 👤 Leod M Mc
- 👤 R Wendeborn
Bibliographic Details
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