Analysis of Solid Waste Samples per Chinese Method HJ 781

Importance of the Topic

Accurate determination of trace and major elements in solid waste is essential for environmental monitoring and pollution control. Regulatory agencies rely on standardized methods to assess contamination levels and ensure safe disposal or remediation of industrial wastes.

Aims and Study Overview

This study evaluates the performance of the Agilent 5800 Vertical Dual View ICP-OES fitted with an AVS 7 switching valve for the analysis of 22 elements in solid waste samples following Chinese national standard HJ 781-2015. The objectives were to streamline method development, identify and correct spectral interferences, and demonstrate reliable results for industrial sludge reference materials.

Methodology and Instrumentation

Solid waste samples were digested using a four acid microwave program combining nitric acid hydrochloric acid hydrofluoric acid and perchloric acid in two stages. The digests were brought to a final matrix of 5 percent HNO3 and 15 percent HCl. An Agilent 5800 VDV ICP-OES with AVS 7 seven port switching valve and SPS 4 autosampler provided rapid sample uptake and reduced carryover. Key software features included IntelliQuant for semiquantitative screening and interference identification Outlier Conditional Formatting for result validation and Early Maintenance Feedback for scheduling consumable replacement. Automated background correction was achieved using Fitted Background Correction and Fast Automated Curve fitting Technique models.

Main Results and Discussion

Method detection limits for all 22 elements were well below those specified in HJ 781-2015. Analysis of NIST SRM 2782 industrial sludge yielded certified element recoveries within ±10 percent. Semiquantitative IntelliQuant screening of additional elements delivered results within ±30 percent of expected concentrations. Spike recovery tests for non certified elements also fell within ±10 percent. A six hour stability test with a quality control solution measured every ten samples showed recoveries within ±10 percent and relative standard deviations below 2.2 percent, confirming excellent precision and robustness.

Benefits and Practical Applications of the Method

• High throughput enabled by rapid sample switching and integrated AVS 7 valve
• Reduced unplanned downtime through early maintenance alerts based on sample count
• Enhanced accuracy via automatic interference detection and correction using IntelliQuant and background correction tools
• Full compliance with Chinese HJ 781-2015 standard for environmental solid waste analysis
• Consistent analytical performance demonstrated by long term QC stability

Future Trends and Potential Applications

Advances in spectroscopic data analytics and machine learning could further automate interference correction and predictive maintenance. Potential extensions include analysis of soils sediments and other complex matrices. Digital twin models may streamline method optimization and reduce calibration efforts.

• Integration of real time data analytics for smart method development
• Automation of sample handling and instrument tuning
• Application to broader environmental and industrial monitoring programs

Conclusion

The Agilent 5800 VDV ICP-OES with AVS 7 switching valve and ICP Expert software provides a robust sensitive and reliable workflow for analyzing solid waste per HJ 781-2015. Automated interference management and maintenance feedback enhance confidence in results and reduce downtime for routine environmental laboratories.

References

1. Solid Waste Determination of 22 metal elements Inductively coupled plasma optical emission spectrometry HJ 781 Standardization Administration of the Peoples Republic of China 2016
2. Agilent IntelliQuant Software Agilent publication 5994-1516EN
3. Fitted Background Correction Rapid automated background correction Agilent publication 5991-4836EN
4. Fast Automated Curve fitting Technique spectral correction Agilent publication 5991-4837EN