Marchwood CCGT Power Station In The UK Saves Circa 300000 Dollars Per Year

Power stations originally designed for base load applications are now increasingly being asked to operate on a two shift stop/start regime. This is more commonly known in the industry as dual shifting

by Brian Woolley | Wednesday 18 February 2015

The consequences of the change in plant operation cannot be ignored. If the plant is not operated correctly or, more importantly, modified properly to handle these changes the lifetime of the components within the plant will decrease enormously.

The changing operational requirements of the plant require that the steam coolers, de-superheater valves, drains, feed water control valves, main steam isolation valves and the turbine quick closing valves are reviewed. These critical pieces of equipment have to be specifically designed to take the new dual shifting process requirements into consideration.

Once this has been done the operational performance of the plant can be improved and wear and tear of systems and components can be controlled and significantly reduced.

• HRSG final desuperheaters (HP & IP) failing in service
• Life expectancy < 12 months
• Expensive to replace and overhaul
• High cost due to plant unavailability

• High quality, well-engineered desuperheaters
• Protected by a steam cooled jacket
• Life expectancy > 12 YEARS!

The problem for James Brown, the Mechanical Engineer at Marchwood Power Station, was that the desuperheater valves installed would fail on average once a year leading to plant unavailability with all the obvious associated costs and some less obvious engineering issues. James had worked with our engineer on a previous project so had confidence in our capabilities and the products that we had previously installed.

The installed desuperheaters were replaced with our cooled desuperheaters each protected by a unique steam cooled jacket. The inspection cycle for the desuperheaters is now greater than 6 years and replacement is now greater than 12 years. Project payback was 1 year.

To arrange a presentation to understand more about the Marchwood cooled desuperheater project and how the cost savings and payback may benefit you please contact Brian Woolley - details below


Brian Woolley
Chase International (CS) Ltd
+44 (0) 1925 755221

Wednesday 18 February 2015 / file under Utilities | Power | Engineering