Home Health Case Studies in Maintenance and Reliability: A Wealth of Best Practices
The power plant was required to produce
The designers planned to install three gas turbines (LM 2500 units, 19 MW). The hot exhaust gases from the turbines would be heated further in three heat recovery steam generators (HRSG) and used for raising high-pressure steam at 125 barg. Each gas turbine (GT) would be integrated with its dedicated HRSG. While the bulk of the HP steam would be used in the process, a part of it would be let down to the medium pressure (MP) steam header at 42 barg., using a back pressure steam turbine (ST 1). This would produce 16 MW. Some of the MP steam would be used to drive a condensing steam turbine (ST 2), which had two stages. At the end of the first stage the steam pressure is at 10 barg, some of which would be extracted and supplied to the low-pressure (LP) steam header. The remainder would drive the second (condensing) stage of the turbine ST 2, generating 17 MW of additional power.
There are four boiler feed water (BFW) pumps to supply water at high-pressure to the HRSGs. Two of these are motor-driven and two are steam turbine- driven. These pumps are large complex equipment, rated at 800 kW, provided with minimum flow controls and other protective devices. Figure 34.1 shows a schematic drawing of the original design.
|< Prev||CONTENTS||Next >|