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Show DEMONSTRA TION OF NEW FLAME-MONITORING SYSTEM AT A PILOT-SCALE, GAS-FIRED COMBUSTION TEST FACILITY Mark Khesin, MK Engineering Inc., N. Andover, MA Rob Girvan, Forney Corporation, Carrollton, TX Abstract The new Burner Diagnostic System (BDS) for flame monitoring and combustion diagnostics is based on analysis of burner flame signatures in the frequency domain. Extensive testing of this system yielded proof that the temporal frequency component of flame radiation (as measured by flame sensors), when properly processed, provides a repeatable, useful indication of combustion parameters. This paper presents results of the pilot-scale testing of the new BDS on a well-instrumented combustion test facility (CTF). The 1.O-MBtu/hr, single-burner, gas-fired CTF was equipped with analytical instrumentation to measure NOx, 02, CO2, CO, and air and gas flows. Three different types of flame sensors were tested in the full range of load changes. The test results demonstrated that the new system can generate four groups of output signals that correlate well with measured burner parameters (NOx, CO, air-fuel ratio), and with flame stability and afford better understanding of the physical nature of these correlations. Introduction To determine the optimum settings for individual burners and continuously maintain these settings, the boiler operator needs an on-line flame-quality monitor that indicates when indi vidual burners are out of tune. If one burner is out of tune, it needs to be identified rapidly and adjusted (using available means of burner adjustment such as burner register settings, register shrouds, or spin vanes); then, NOx, combustibles, and excess air can be minimized. Identifying the out-of-tune burners and correcting air- and fuel-flow distributions will improve the boiler performance and lead to lower prices on future 10w-NOx burner retrofits. With the support of Fireye Inc. and selected electric utilities, MK Engineering Inc. and Forney Corporation are currently developing a new method of combustion diagnostics based on analysis of flame turbulence in the frequency domain. In this paper, we describe results of our recent tests on a pilot gas burner and suggest likely practical applications of the new system. |