Spark-Induced Breakdown Spectroscopy: A New Technique for Monitoring Heavy Metals

Abstract

This paper presents the development and testing of a new real-time monitoring technique for heavy metal aerosols and particulates in air based on spark-induced breakdown spectroscopy (SIBS). The technique is based on temporally resolved atomic emission resulting from excitation of the aerosol-laden air sample in a high-energy electrically generated spark. A complete prototype monitor comprised of spark power supply, sample chamber, bandpass-filtered radiometric detector, and computer for real-time data acquisition and display has been assembled, calibrated, and tested. The lower limits of detection for lead and chromium are 10 μg/m3. The monitor has been successfully applied as a continuous emissions monitor for lead and chromium in a simulated combustion flue gas at a joint EPA/DOE test, for fugitive chromium emissions above a hard chrome plating tank, and for airborne particulate lead at an indoor firing range. The monitor has also demonstrated the capability to detect cadmium, mercury, selenium, antimony, arsenic, uranium, and thorium.