Precision of on-line analysers and sampling systems
As on-line analysers grow in popularity as a quality control tool in bulk materials handling, so does the discussion around precision of such instruments and the precision of the sampling systems to which they are calibrated. This topic will be explored during plenary sessions at this years World Conference on Sampling and Blending in Bordeaux, France, in June.
Real Time Instruments CEO, Dr James Asbury, in collaboration with Geoffrey J Lyman of Materials Sampling and Consulting, will present a paper that details a simple and relatively inexpensive way of determining the precision of sampling systems and on-line analysers.
The methodology can be applied to applications where a data base of output values from the sampling system or online analyzer can be accessed and where there exists serial (auto) correlation in the data sets. When error terms from different (usually adjacent) time periods are correlated, we say that the error term is serially correlated. Serial correlation occurs in conveyor belt sampling systems when the errors associated with a given time period carry over into future time periods. This is almost always the case with crossbelt sampling, sample preparation and analysis.
The method that will be described at the conference will illuminate attendee’s to the importance of ensuring that the sampling system that the online analyser is referenced too is unbiased and very precise. An appreciation of such is key to gaining the full value of online technologies such as prompt gamma neutron activation analysis (PGNAA) duel energy (DUET), and natural gamma.
Further information is available from RTI.