Since 1993, I have been developing instrumentation for measuring
ultra-trave levels of sulfur dioxide in the atmosphere. I was a co-developer
of the Diffusion Denuder/Sulfur Chemiluminescence Detector (DD/SCD). The
DD/SCD has a detection limit of < 20 parts-per-trillion by volume (pptv)
for a 10 minute measurement. The DD/SCD has been validated as a sensitive,
interference-free technique in an experiment sponsored by the National
Science Foundation (NSF).
Currently, a new version of the DD/SCD called the Continuous Sulfur
Dioxide Detector (CSD) is being developed by myself and my advisor, Dr.
Richard Benner. The CSD benefits from a redesigned denuder manifold and
optimized fluid dynamics within manifold and SCD burner. Novel digital
signal processing and phase-locked amplification of the detector signal
enhances the precision and temporal resolution of the CSD. What this means
is that the CSD is capable of measuring low level sulfur dioxide (<
20 pptv) in less than one minute. The high temporal resolution and sensitivity
of the CSD allows for more detailed study of the atmosphere form a moving
platform such as an airplane. The DD/SCD and CSD have applications in many
fields where sulfur dioxide is found in air, including process stream monitoring,
pollution source monitoring and pollution receptor/compliance monitoring
as required by the Clean Air Act.