skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A CAVITY RING-DOWN SPECTROSCOPY MERCURY CONTINUOUS EMISSION MONITOR

Technical Report ·
DOI:https://doi.org/10.2172/823949· OSTI ID:823949

The construction of the sampling system was completed during the past quarter. The sampling system has been built on a 3 feet x 4 feet x 2 inch breadboard table. The laser system, all the associated optics, and the mounts and hardware needed to couple the UV light into the fiber optic have also been condensed and placed on an identical 3 feet x 4 feet x 2 inch breadboard table. This reduces the footprint of each system for ease of operation at a field test facility. The two systems are only connected with a fiber optic, to bring the UV light to the CRD cavity, and a single coaxial cable used to apply a voltage to the diode seed laser to scan the frequency over the desired mercury transition. SRD software engineers applied a couple of software fixes to correct the problems of the diode seed laser drifting or mode hopping. Upon successful completion of the software fixes another long-term test was conducted. A nearly 3 day long, 24 hours/day, test was run to test out the new subroutines. Everything appeared to work as it should and the mercury concentrations were accurately reported for the entire test, with the exception of a small interval of time when the intensity of the UV light dropped low enough that the program was no longer triggering properly. After adjusting the power of the laser the program returned to proper operation. With the successful completion of a relatively long test SRD software engineer incorporated the new subroutine into an entirely new program. This program operates the CRD instrument automatically as a continuous emissions monitor for mercury. In addition the program also reports the concentration of SO{sub 2} determined in the sample flue gas stream. Various functions, operation of, and a description of the new program have been included with this report. This report concludes the technical work associated with Phase II of the Cavity Ring-Down project for the continuous detection of trace levels of mercury. The project is presently gearing up for additional testing in preparation for a field test to be conducted at the DOE/NETL pilot plant facility in Pittsburgh, Pennsylvania.

Research Organization:
Sensor Research and Development Corporation (US)
Sponsoring Organization:
(US)
DOE Contract Number:
FC26-01NT41221
OSTI ID:
823949
Resource Relation:
Other Information: PBD: 31 Mar 2004
Country of Publication:
United States
Language:
English