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Show A165E713.T • 3 characterize air toxics and other chemical emissions from gas-fued combustion turbines to provide data for EPRI's PISCES project, GRI, and participating utilities • obtain air toxic emissions data for use in anticipation of further regulation at the state and local level • evaluate the impact of unit design and operating parameters on air toxic emissions - unit type - fuel components - unit load - NOx control techniques - unit surfaces • perform a screening health risk assessment of the utility combustion turbines in order to place the emissions results into context GAS TURBINE DESCRIPTIONS Table 1 lists the manufacturer and model of the two utility combustion turbines and seven industrial gas turbines for which emissions measurements are presented. For the two utility combustion turbines, the maximum continuous rating (MCR) , in MWe, is the maximum electricity generated by the turbine/generator set. For the seven industrial gas turbines, the MCR, in units of MW eq' is the maximum power delivered to the pipeline compressor. The two utility combustion turbines tested by Carnot are used for electricity generation during times of peak load demand. The Westinghouse 501AA combustion turbine was commissioned in 1972 and is capable of burning either natural gas or distillate fuel oil. No NOx controls are installed on this unit. The General Electric Frame 7 was commissioned in 1992 and fues natural gas only. The unit is equipped with water injection into the front of the turbine combustor, cooling the combustion gases and reducing NOx emissions from the turbine. The seven industrial gas turbines drive compressor sets in the gas transmission market and are representative of the industrial turbine population. The only one of the seven turbines with NOx controls is the Solar Mars T14000 SoLoNOx'DI industrial gas turbine tested, which is equipped with the SoLoNOx'DI dry 10w-NOx combustor. The combustor operates in a turbulent diffusion mode during operation below 50 % MCR with NOx emissions increasing linearly with load. Above 50 % MCR, the combustor switches to lean premixed combustion, and NOx emissions decrease sharply and remain essentially constant up to peak load. OVERVIEW OF THE TESTING PROGRAMS AND TEST MATRICES USED The testing programs at the two utility combustion turbines included measurement of trace metals, semi-volatile organics, volatile organics and formaldehyde at 100% of MCR. Measurements of volatile organics and formaldehyde were conducted at three reduced load levels to determine the effect of turbine operation on the emissions of these species. For all test |