EFFECT OF VARIATIONS IN A PULP FLOW ON SAMPLING AND PROCESS MEASUREMENTS
Tuomo Timonen, Jouko Halttunen
Abstract:
A pulp suspension flowing in a pipe has a tendency to form a profile: The properties of the pulp vary significantly in a cross-section of the flow. This causes problems both in online-measurements and sampling. The importance of representative sampling is further emphasized by the fact that samples taken are often used as reference in calibration of measurement instruments.
The problem of representative sampling and the variation of quality in a pulp flow were studied using equipment with which it was possible to take samples from different depths in the flow and thus determine the variations.
Experimental testing was conducted in different process conditions and with different pulp types. The results of the tests showed that the quality variations in a pulp flow were more profound than initially thought: Several pulp properties have significant profiles within the flow that depend on the type of the pulp and the flow conditions. The variation of pulp properties is large enough to somewhat affect all measurements made from the flow in question.
The findings of the study suggest new guidelines for sampling and installing instrumentation when a pulp suspension flow is measured.
Keywords:
Pulp, Flow, Sampling
Download:
PWC-2003-TC9-009.pdf
DOI:
-
Event details
Event name:
XVII IMEKO World Congress
Title:

Metrology in the 3rd Millennium

Place:
Dubrovnik, CROATIA
Time:
22 June 2003 - 28 June 2003
 Back