Analysis of Direct Reduced Iron and Hot Briquetted Iron with ARL EQUINOX 100 Benchtop XRD

Significance of the Topic

Steel production continues to grow globally, driven by industrial demand. Traditional blast-furnace routes require high temperatures and premium coke, whereas direct reduction of iron (DRI) offers an energy-efficient alternative. Monitoring the quality of DRI and subsequent Hot Briquetted Iron (HBI) is critical for consistent downstream steelmaking. Key parameters include total iron content, metallic iron fraction and ferrous oxide concentration, which are challenging to determine by rapid spectroscopic methods.

Aims and Study Overview

This work demonstrates a rapid, reliable approach to quantify phase composition in iron ores and briquettes using the Thermo Scientific ARL EQUINOX 100 benchtop X-ray diffractometer. The goal is to replace time-consuming wet chemistry assays for Fe(total), Fe(metallic) and FeO(total) by applying Rietveld refinements of XRD patterns.

Methodology and Instrumentation

Fine-powdered samples of sinter and HBI were measured in reflection geometry over a five-minute scan using Co Kα radiation. Phase identification and quantification were conducted with MDI JADE 2010 software and the ICDD PDF4+ database. Instrumentation details:

• ARL EQUINOX 100 benchtop XRD with micro-focus Co tube (15 W)
• Curved position sensitive detector for simultaneous, real-time peak acquisition
• No external cooling or peripheral systems required

Main Results and Discussion

Rietveld refinements revealed that the sinter sample contains 16.5 wt % FeO(total) with major phases including magnetite and silico-ferrite. The HBI showed total iron content of 97.1 wt %, metallic iron (including cementite) at 91.4 wt % and 1.2 wt % carbon. These values align with expected quality parameters for production control.

Benefits and Practical Applications

The benchtop XRD methodology enables routine, on-site quality control of iron feedstocks without wet chemistry. Fast, automated data collection and processing reduce manual errors and improve laboratory throughput. Users can integrate this system directly into production environments for real-time monitoring.

Future Trends and Potential Applications

Advances in detector technology and automated Rietveld workflows will further decrease analysis time and increase precision. Portable benchtop XRD units could enable in-field monitoring at mining sites and reduction plants. Integration with digital quality management systems offers potential for predictive process control in steelmaking.

Conclusion

The ARL EQUINOX 100 benchtop XRD coupled with Rietveld refinement software provides a rapid, accurate alternative to wet chemical assays for evaluating Fe(total), Fe(metallic) and FeO(total) in sinter and HBI samples. Its ease of use, portability and automated data processing make it well suited for routine industrial quality control.

References

No external literature references were listed in the original application note.