| dc.description.abstract | Competition has been a prime mover in the energy industry and there is the drive to increase performance of steam turbine-driven equipment. Availability of a unit is also critical to the operation of a plant and has also provided the fundamental reason why many utilities have chosen to upgrade existing steam turbines rather than replace obsolete components. Retrofitting older generation turbine plants with present day steam-path, can yield substantial performance improvement, giving extra revenue from increased generation, reducing fuel consumption while also benefiting the environment through reduced emissions. Also as competition revolutionizes, the power generation industry is taking a close look at aging steam turbines. They are evaluating whether refurbishment or upgrades to aging steam turbines represent cost effective opportunities for lowering maintenance cost and avoiding forced outages as well as increasing unit output. This has called for the improvement of the unit heat rate, increased capacity and improving reliability of the unit in other to stay competitive. The unit turbine at ABC Plant has experienced solid particle erosion (SPE) which has increased the cost to operate the unit, decreased efficiency, and caused degradation in heat rate and unit availability. solid particle erosion has caused the station millions of dollars loss in revenue from steam turbine operation, maintenance and reliability. Solid Particle Erosion occurs when exfoliated particles from boiler tubes, super heater and reheater tubes are carried over to the turbine through the steam path and the cost that is associated with regular inspection, repair or replacement of damaged components has been high. The station has been urged to come up with a solution to minimize or reduce the solid particle erosion effects on the turbine. As part of the solution, the station is looking at the different most accepted means of combating Solid Particle Erosion. They are steam turbine blade coating, improved nozzle design and modification in the steam path which is the dense pack design. The dense pack turbine section performance is the latest evolution proposed by General Electric and the design limit does not change with the dense pack design. The design goal is to put the most efficient steam path into an existing high pressure shell. The high-efficiency steam path will produce a lower heat rate and increased output for the same steam flow. The design parameters utilized to increase efficiency such as bucket, nozzle solidity and reduced rotor diameters also had the benefit of reducing solid particle erosion. The dense pack supplies the user which is the station with a redesigned steam path including a new bucketed rotor, diaphragms, and an inner shell. The XYZ Power Station was originally owned by BBB Company and subsequently purchased by ABC Energy Generating in 2002. The station is located near ABC, Illinois, west of the Illinois River. It has one steam turbine generator with a net generation of 366MW.
This project is divided into three phases; the first phase of this project involves looking at the problem statement which is the effects of solid particle erosion (SPE) and propose a solution for SPE problem by implementing one of the proposed solutions to combat Solid Particle Erosion, part of the solution which will involve turbine blade coating also called sandblasting will be implemented during the fall 2005 outage and the final solution which will involve the installation of the dense package will be implemented in 2007. The first part of the project was implemented during the fall 2005 outage in conjunction with generator electrical testing and inspection. The second phase of the field project will look at the proposed boiler modification project in 2007 and the dense pack project in 2007 which all when implemented will help achieve the end results of this project which is improving the performance of the steam turbine generator. The third phase will look at how the output of the steam turbine generator can be increased or improved by operating at design values and improving the heat rate and efficiency using past standard heat rate testing results assuming the boiler modification project has been completed and the dense pack project has also been completed. | |
