Delicate Fins on ACC Protected by Online Cleaning Technology
Safety was paramount when one of Britain’s newest power stations chose descaling and inspection specialist Tube Tech to clean its massive Air Cooled Condenser (ACC).
The Apex finned ACC was one of the largest in Europe when it was commissioned in February 2001.
With a 260-acre surface area for the heat exchanger, the ACC takes up nearly one third of the site of the Combined Cycle Gas Turbine Station operation which is owned by a subsidiary of the Texas-based Energy Corporation.
- Lowered performance on the steam driven turbine prompted DCL to consider an additional clean of the finned tube bundles from inside. This would deal with debris sucked up by the 36 enormous cooling fans when construction work was still being completed during commissioning.
- Tube Tech was the only company in the competitive tender which could satisfy the desired criteria of using the existing walkways to clean the tubes 35ft above. “Other companies had advised the use of rope access methods or secondary staging to reach the full extent of the tube surfaces,” explained a DCL spokesman.
- Only Tube Tech advised they would be able to carry out the cleaning in the way considered the safest option. Faced with the largest and highest Apex Air Cooled Condenser (ACC) it has tackled – covering 34,000 square metres of bare surface – Tube Tech used several different systems and also developed an additional technique which involved a hi-tech light weight alloy system and a handling process specific to the site.
- Mike Watson, Managing Director of Tube Tech said: “We created a mock-up prototype and tested its effectiveness on a lifesize replica at our premises. The final result exceeded expectations.”
DCL acknowledges that the effectiveness of the clean has brought measurable performance improvement and more than justified the cost. The client was impressed by Tube Tech’s own safety approach. The spokesman added; “The Tube Tech and DCL safety procedures were strictly adhered to. There was not a single incident or near-miss report.” Since then Tube Tech has again competed successfully to win a term agreement to carry out further maintenance cleaning at the site. Tube Tech carried out the first clean in 16 days and has guaranteed to complete further cleaning of the ACC in 10 days.