The Potential for XRF & LIBS Handheld Analyzers to Perform Material Characterization in Scrap Yards

Scrap yards have long been responsible for identifying and sorting specific alloys from large quantities of mixed metals by means of visual and cognitive recognition with the aid of a few standard tools (a magnet, file, acids, and/or grinding wheel). Performing visual inspection successfully requires extensive knowledge obtained through years of experience physically handling material. This level of expertise cannot reasonably be expected of all those in the operations process but, the right instrumentation in capable, well-trained hands could work to bridge the difference between an expert and a novice. Handheld analyzers (HHs) that utilize X-ray fluorescence (XRF) and laser induced breakdown spectroscopy (LIBS) technology offer a level of technological assistance that could improve identification during the inspection process. Although the technology harnessed by these instruments is not new, the accessibility of it is- which has allowed the functionality, performance, and purpose of these HHs to expand. Subsequently, the attractiveness of these instruments goes beyond being able to obtain results similar to laboratory analysis. HHs are in-field ready, and the ergonomics, safety settings, read times, data sharing and accessibility are continually improving. Additionally, the costs of HHs are shrinking; this coupled with the opportunity to improve profit and avoid loss through reducing incorrect identification produces the more immediate return on investment (ROI) that yards require. Currently, we have a good indication of how HHs perform on material that has clean, smooth, uncoated surfaces but, what we aim to find is their response when used on “unprepared materials,” like those coming out of stock that are old, used, weathered, and/or warped. For these instruments to be deemed useful for inbound inspection/ identification purposes, it is crucial to understand and evaluate their limitations on scrap that is not altered and thus, true to a yard setting. Our results indicate that in their current state, HHs can inform and verify content for a significant range of materials, but there are still metal types and conditions that exist that lead to unreliable reporting of compositional percentages. Graphical Abstract