ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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SECTION 2.0:PROJECT DESCRIPTION Intermediate-pressure feedwater will flow through the IP economizers to the IP steam drum,where a saturated liquid state will be maintained. Next,the saturated water will flow from the steam drum through downcomers to the inlet headers of the IP evaporator. The saturated water will flow upward through the IP evaporator tubes by natural circulation. Saturated steam will form in the tubes while energy from the combustion turbine exhaust gas is absorbed. The IP-saturated liquid/vapor mixture will then return to the steam drum, where the two phases will be separated by the steam separators in the drum. The saturated water will return to the IP evaporator while the vapor passes to the IP superheater inlet. The saturated steam (vapor) will pass through the IP superheaters to the IP steam turbine inlet. High-pressure feedwater will flow through the HP economizers to the HP steam drum, where a saturated liquid state will be maintained. Next,the saturated water will flow from the steam drum through downcomers to the inlet header of the HP evaporator.The saturated water will flow upward through the HP evaporator tubes by natural circulation. Saturated steam will form in the tubes while energy from the combustion turbine exhaust gas is absorbed. The HP-saturated liquid/vapor mixture will then return to the steam drum, where the two phases will be separated by the steam separators in the drum. The saturated water will return to the HP evaporator while the vapor passes to the HP superheater inlet. The saturated steam(vapor) will pass through the HP superheaters to the HP steam turbine inlet. The LP evaporator will function similarly to the HP and IP evaporators. The saturated LP steam (vapor) will pass through the LP superheater to the LP steam turbine inlet. A duct burner system will be installed in the HRSG that can be used to increase steam generation and operating flexibility and will improve steam temperature control. The duct burner system will burn natural gas. The duct burner system for the HRSG will be sized to release up to approximately 220 million British thermal units per hour (MMBtu/hr) on an HHV basis. The HRSG will be equipped with an SCR emission control system that will use ammonia vapor in the presence of a catalyst to reduce the NO,,concentration in the exhaust gases. The catalyst module will be located in the HRSG casing. Diluted ammonia vapor (NH3)will be injected into the exhaust gas stream through a grid of nozzles located upstream of the catalyst module. The subsequent chemical reaction will reduce most of the NOX to nitrogen and water. An oxidation catalyst will control CO emissions. 2.1.6.2.1 Steam Turbine System The steam turbine system will consist of a condensing steam turbine, gland steam system, lubricating oil system,hydraulic control system, and steam admission/induction valving. The steam turbine will drive a hydrogen-cooled, synchronous generator. Steam from the HRSG HP, IP,and LP superheaters will enter the respective steam turbine sections through the inlet steam system. The steam will expand through the turbine blading, driving the generator. On exiting the turbine, the steam will flow into the condenser. 2.1.6.2.2 Auxiliary Boiler The auxiliary boiler will be used during pre-start activities and during the initial phases of start-up to generate steam for sealing,heating/re-heating the hotwell condensate (condenser 2-16 SAC/371322/082340003(LEC_2.0_PROJECT_DESC.DOC)