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Title: MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED PHOTOACOUSTIC EFFECT TO MEASURE UNBURNED CARBON

Technical Report ·
DOI:https://doi.org/10.2172/835636· OSTI ID:835636

Three test instruments are being evaluated to determine the feasibility of using photoacoustic technology for measuring unburned carbon in fly ash. The first test instrument is a single microwave frequency system previously constructed to measure photoacoustic signals in an off-line configuration. A second off-line instrument was constructed based in part on lessons learned with the first instrument, but which also expands the capabilities of the first instrument. Improvements include a control loop to allow more constant microwave power output and an ability to operate over a range of microwave frequencies. The third instrument, the on-line version of the fly ash monitor, has been designed, constructed, and initial efficiency tests have been conducted on the monitor's electrical components. Off-line photoacoustic microwave spectra of fly ash and coal were collected and analyzed, and the spectra demonstrated a linear correlation between the photoacoustic response and the carbon content in either fly ash or coal. Modifications were made to the on-line fly ash monitor to incorporate a dual-accelerometer system that would provide active noise control. Several experiments were conducted with flowing and non-flowing fly ash samples.

Research Organization:
Iowa State University (US)
Sponsoring Organization:
(US)
DOE Contract Number:
FC26-01NT41220
OSTI ID:
835636
Resource Relation:
Other Information: PBD: 1 Oct 2004
Country of Publication:
United States
Language:
English