19 November, 2016

Calibration

Daily composite samples are collected in pots on the backside of the xrf instruments secondary sampling tanks

Calibration maximizes productivity

How often it is needed to collect a series of calibration samples depends on the process and the ore. Some of our customers do it several times each week and others do it on a monthly bases or even more rarely.

Trend curves from EDXRF analyzer, shows high correlation between online analysis and laboratory analysis of the same sample

The diagram shows Boxray measurements on copper, zink, lead and silver as as curves. Spot samples for corresponding elements is shown as dots. The data was collected over a period of three weeks on a lead and zink ore. The lead contained some copper and silver as well. The Boxray measurements correspond very well to the laboratory evaluated spot samples. During a period this long it covers both high and low grade samples, high and low percent solids and differences in ore composition. The Boxray on-stream analyzer can accommodate for these variations and deliver accurate assays in every case.

Regardless of the time interval we strongly recommend to do this on a regular basis. The Boxray on-stream analyzer is a fine tuned instrument. It makes sense to keep it precisely trimmed in order to maximize the productivity.

Remote desktop connection for convenience

When the calibration samples have been collected and analyzed at the lab the personnel use the remote desktop connection from the convenience of their office to enter the results into the analyzers sample database. When this is completed the operator can select which samples to use. Usually the latest few samples, and the analyzer will then suggest what multiplying factor to adjust in order to get analyses tuned.

The same procedure can be used for the daily composite samples.

Go through collected data

We also recommend going over the collected data and calculating new regressions once or twice a year. This is a specialist task and can be performed by a trained person on site or by one of our service engineers. Once again the remote desktop connection can be used. Either from the lab personnel’s offices or from our local or global headquarters.