Keadby Power Station

Scottish & Southern Energy (SSE) is a major energy supply company in the UK serving customers from more than 150 sites across the UK, operating over 10,000 MW of generation capacity. SSE are the UK’s second largest generation business, with ownership interest in over 100 thermal and renewable power stations. SSE are the UK’s leading generator of renewable energy, owning and operating almost half of the UK’s total renewable generation capacity, including the UK’s largest wind farm.

The gas fired SSE Keadby power plant, based in England operated 2 x General Electric (GE) Fs9FA gas turbines each generating 255.6 MW (iso), the combined total generation is 720 MW. Since the plant start-up, more than 10 years ago, gas turbine compressor cleaning has been performed using the standard wash system offering from GE for both online (fired) compressor washing and offline (on-crank) compressor washing. The online wash system has had limited use because of a partial ban by GE on online compressor cleaning due to potential compressor blade erosion and liberation as a result of poor online wash injection processes. Offline washing using the GE system has its own set of issues and in 2003 SSE issued a tender to implement improvements to the current wash system.

The GE offline wash system problems are as follows:

• Flooding of the exhaust duct resulting in premature damage and failure of the exhaust bellows.
• Flooding of the lower half fuel nozzle pig tails – 2 x 8 hours of labour time
• High volume of wash system waste fluid requiring local storage and disposal
• Wash delivery system very labour intensive and many components obselete

The prime objective of the SSE Keadby tender were to resolve the listed issues above while improving the overall washing efficiency of the system and utilise as much equipment as possible from the existing wash system.