Ferrous scrap metals for remelting into new iron or steel products have historically been bought and sold on the basis of broad categories based mainly on physical properties of the materials, rather than the chemical properties. One of the most important considerations in the blending of scrap mate rials for remelting is their chemical composition, particularly with regard to residual elements that cannot be removed from the melt and can only be reduced in content by dilution. Given the heterogeneity of most common grades of scrap, it is very difficult to take representative samples that can be analyzed by spectrographic or other analysis methods to get any reasonable estimation of the overall chemistry of a lot of material, let alone an estimation of the chemistry of any charge-sized sample of the materials. Prompt Gamma Neutron Activation Analysis (PGNAA) has been used in the coal and cement industries for several years for on-line real-time analysis of materials, and research has been completed to apply this analysis technique to the analysis of ferrous scrap materials. This paper will describe the PGNAA process for chemical analysis and the pilot testing conducted for the proof of concept of its application to the analysis of ferrous scrap metals and the results from those pilot tests.
展开▼
