Patent ID: 8855809

Claim:
A material sorting system, comprising: a conveyor configured to convey pieces of metal; an x-ray source configured to irradiate one or more of the pieces of metal with incident x-rays as they are conveyed by the conveyor to generate fluoresced x-rays from the one or more pieces of metal and transmitted x-rays transmitted through the one or more pieces of metal; an x-ray fluorescence detector array configured to detect the fluoresced x-rays and produce x-ray fluorescence data for at least a first piece of metal of the one or more pieces of metal; an x-ray transmission detector configured to detect the transmitted x-rays and produce x-ray transmission data for at least the first piece of metal; and at least one processor configured to: obtain data for a plurality of characteristic x-ray fluorescence peaks; identify a plurality of peaks of the x-ray fluorescence data as corresponding to respective ones of the characteristic x-ray fluorescence peaks; determine, using the peak identification, the presence of a plurality of materials in the first piece of metal; obtain data for a plurality of predetermined sorting categories, at least two of the sorting categories being associated with one or more materials; and identify at least one sorting category for the first piece of metal based at least in part on the x-ray transmission data and by comparing the determined plurality of materials in the first piece of metal with the sorting categories.