A distance correction method for improving the accuracy of particle coal online X-ray fluorescence analysis - Part 2: Method and experimental investigation

The distance from X-Ray Fluorescence (XRF) spectrometer to sample surface always changes with the different coal's particle sizes, resulting in the inaccuracy of online XRF measurement. To improve the accuracy of particle coal online XRF analysis, a distance correction method was established elaborated by iteration, which was based on the relationship between the XRF intensity and the distance. In order to verify the effectiveness of this method, five different particle size coal samples with same components have been measured by the online XRF analyzer directly above the conveyor belt, in the meanwhile, the distances between XRF spectrometer and samples' surface were obtained by a laser rangefinder. The results showed that the average distances are decreased with decreasing the particle size. By comparing the results of before and after applying the distance correction method, we demonstrated that the measurement accuracy of online XRF analysis for particle coal can be significantly increased. The distance correction method can be used for the development of online XRF analysis techniques applicable for real-time industrial processes.