Posted to News on 27th Apr 2022, 14:42
Sulzer supplies pump technology to combined cycle gas turbine power plant
In a fast-changing energy market, the Keadby 2 power station in Lincolnshire, UK has been designed to offer class-leading efficiency, flexibility, and reliability, with Sulzer’s innovative pump technology playing a key role.
Built by SSE in collaboration with Siemens, the 840 MW Keadby 2 power station is one of the most advanced gas-fired power plants in the world. Scheduled to commence operation in 2022, the facility will be the first commercial deployment of the 50 Hz version of Siemens’ SGT-9000HL gas turbine.
To achieve its overall efficiency target of 63%, Keadby 2 is using a 1-on-1 design, with a single gas turbine linked to a single steam turbine. The equipment and all critical ancillary components must be able to offer extremely high efficiency levels across a wide range of loads. When it came to the major pumping applications, the Keadby team turned to Sulzer for the most advanced technology available.
The plant will use two of Sulzer’s state-of-the-art feedwater pumps, MD200-400, which have been upgraded in close collaboration with leading gas turbine manufacturers, including Siemens, specifically to meet the requirements of the new generation of H-class turbines. The pumps are set up in a 2x100% configuration, with one duty unit and the other on standby.
Patrick Welz, EMEA head of tendering for Sulzer, explains: “Thanks to their advanced hydraulic and mechanical design, our pumps will operate at an efficiency of more than 81%, requiring a rated power of only 5.1 MW to achieve suction and discharge flows of 860 m3/hour and 730 m3/hour respectively at a head of 2,200 m.”
One key feature of the Sulzer pump is its hydraulic thrust balancing system, which includes a balance drum and thrust bearing that have been developed for a long life under extreme operating conditions. Combined with bearings and a lubrication system that have both been optimized for the application, this greatly improves the ability of the pump to manage overrun situations where it may be required to operate outside its normal performance envelope.
The balance drum and bearing arrangement also help the feedwater pumps to achieve class-leading reliability and availability, with a longer service life and less requirement for maintenance than alternative designs. That is an especially important attribute for the Keadby 2 project, which will feature the first HL-class turbine in Europe to be operated under a 15-year long-term service contract.
Sulzer was also selected to deliver condensate extraction pumps and cooling water pumps as part of the same project. Sulzer’s expertise in pump design and its ability to engineer every pump to exactly match the specific application within a short timeframe meant the new pumps could manufactured and delivered quickly.
The condensate extraction pumps came from the SJD-CEP series of vertical pumps and offer low net positive suction head (NPSH) as well as high head per stage and excellent efficiency figures. Specifically designed for this application, the Sulzer pumps are designed for extended, maintenance-free operation and have been installed in many power generation plants.
The cooling water pumps were selected from Sulzer’s SJT/SJM-CWP range, which as a fabricated pump offers much lower weight and higher efficiency compared to equivalent cast iron designs. These pumps can be quickly manufactured to meet the performance requirements of the cooling system and also delivery high efficiency figures and decades of reliable service.
