Improved method of and apparatus for determining the shives content or the content of fibre bundles of a pulp

摘要

1100128 Determining consistency of pulp suspension OSAKEYHTIO KESKUSLABORATORIO CENTRALLABORATORIUM AKTIEBOLAG 8 April 1965 14927/65 Headings D2A and A8B Apparatus for the determination of the shives content or content of the fibre bundles of a pulp, provides a restricted path including a slit 10, the slit being dimensioned to retain particles exceeding a pre-selected size, pressure air for passing a liquid suspension of pulp at a selected flow-rate through the slit 10, and means for widening the slit when a pre-selected decrease in flow through the slit 10 has been detected. In operation, the width of the slit 10 between a body 9 and tube wall 8 is adjusted to the pre-selected width and the height of an overflow tank 4 is adjusted to set the liquid level in tube 7. The pulp is fed from a storage chamber 1 through a dilution chamber 4 to the tube 7 where it is drawn down by air pressure towards the slit 10. If there are shives greater than the pre-selected size present in the suspension, the slit will become clogged up causing the liquid level to rise in the tube 7 actuating a switch 18 to operate a relay 20 opening a valve 15 which controls an air pressure supply supporting the body 9. The body 9 then falls thus widening the slit 10, the shives are rinsed away by the flowing liquid, and the level of the liquid falls to its original level. The time taken for the equilibrium level to be reached is a measure of the consistency of the pulp. The number of rinsings during the passage of the pulp suspension, each being indicated by operation of the relay 20, are connected by a counter 22 as a measure of the shive content of the pulp.