GT26 CCGT Power Plant - HRSG Casing Pumpable Hotspot Repair in Ireland - DEKOMTE de Temple Kompensator-Technik GmbH

GT26 CCGT Power Plant – HRSG Casing Pumpable Hotspot Repair in Ireland

Whilst regular insulation repairs and maintenance can be intrusive, laborious and time-consuming, pumpable insulation lowers cost and shortens downtime.

Client: Dublin Bay Power Plant

Dublin Bay is a single-shaft combined cycle gas turbine power plant with a capacity of 417 MW. Total output is equal to about 9% of peak demand in Ireland, and has an efficiency of 50%. It consists of one Alstom GT26B, 265 MW gas turbine and one Alstom 152 MW steam turbine.

Total Output:	417 MW
Date Operational:	2002
Location:	Dublin Bay, Ireland
Primary Fuel:	Natural Gas

Original: Breakdown of Insulation in HRSG Casing

Dublin Bay discovered insulation loss in the internally insulated casing of HRSG. The plant had repaired the liner plate issues and renewed the insulation, but the location was still showing hotspots.

Regular problems caused by hot-spots:

Contact and deformation of the liner plates
Casing integrity and deformation
Surrounding overheating of adjacent equipment

Solution: DEKOMTE Hotspot Repair Technology - Pumpable Insulation

Whilst regular insulation repairs and maintenance can be intrusive, laborious and time-consuming, pumpable insulation lowers cost and shortens downtime. Pumpable mastic is delivered in 20kg shipping containers. It is removed from these containers and emptied into the hopper of the pump. Movement or breakdown of mineral wool and ceramic fibres will leave a void that will create the hot spot. The mastic that is pumped in is relatively heavy, which compresses the remaining fibre blankets, causing more mastic to be used to fill the void.

In the progression photos below, you can see the pumpable insulation has successfully reduced the external surface of the door casing. In the last sequence, the nozzle of the pump is still attached, demonstrating just how quickly pumpable insulation cools an area. DEKOMTE successfully pumped 19 x 20kg containers of pumpable insulation into the GT exhaust duct, eliminating the hot spots.