The steam turbine in this offering/proposal is shown above without the electric generator and the exciter. The subcritical, superheated steam from the boiler enters the high pressure (HP) section of the turbine and then exits after expansion back to the reheater section of the boiler where it is superheated and then returns to the intermediate pressure (IP) section of the steam turbine where it expands and then exits directly to the low pressure (LP) section of the steam turbine where it flows in two directions in each of two-flow sections and finally exhausts into the condenser from four flow openings. The electric generator which converts the rotational mechanical work of the steam turbine into electricity is not shown above. Steam turbine generator and auxiliaries, brand new and never installed are stored in a climate-controlled warehouse awaiting shipment to the site of a new owner.
This turbine-generator unit selection is excellent because it is centered on General Electric Company’s philosophy of long-term service reliability and efficiency. The unit comes with single reheat, and seven steam extraction points for closed feedwater heaters and deaerator, all of which ensure excellent steam cycle efficiency and overall improvement in plant heat rate performance. Many units of this type are in service in the United States and throughout the world and have had good track records in service.
Available cooling system resources at the destination site may be significantly different from the site for which the system was originally designed in the United States. Stodad Corporation is in a position to advise any purchaser of this unit on the cooling system design at the destination site which will allow close approach to the original low-pressure exhaust design pressure unit rating of the turbine-generator. The cooling resources at the destination site are important consideration including proximity to the load, transmission system and other factors.
The Alstom Vertical Wall, Sliding Pressure Supercritical steam generator for this plant has been designed for combined operation using Once-Through Technology. This steam generator has no boiler drum and is of the vertical tube walls as opposed to spiral wound or helical tube furnace. The fuel handling includes conveying the coal from the plant yard for holding in bunkers, weighing, pulverization and feeding to conventional, tangential firing burners. This creates a
single rotating flame envelope (vortex) that produces a uniform and consistent heat profile across the furnace walls over the operating load range. Due to aerodynamics, the fuel and air are mixed throughout the furnace, resulting in high efficiency combustion. Tangential firing also provides the following advantages: