AN IMPROVED BULK MATERIAL ANALYSER FOR ON-CONVEYOR BELT ANALYSIS

摘要

The present invention relates generally to bulk material analysers suitable for the direct on-line analysis of materials such as coal and minerals. It is targeted particularly at direct on-conveyor belt analysis. It includes: a shielded enclosure defining an analysis zone within it and having a passageway through it to allow transport of bulk material through the analysis zone. At least one neutron source (1, 4) and at least two gamma-ray detectors (3, 5) are disposed within the enclosure to measure gamma-rays produced in the bulk material by both the neutron inelastic scatter and thermal neutron capture processes. A neutron source and a gamma-ray detector are arranged in either a transmission or backscatter geometry. A second gamma-ray detector is arranged either in a transmission or backscatter geometry with or without using a second neutron source. The arrangement of detectors is such that the bias in the spatial response of each, that is caused by the relative attenuation of neutrons and gamma-rays in the bulk material, at least partly compensates for bias in the spatial response of the other.