Attero Steam Turbine in Moerdijk

The assignment

The assignment involved the construction of a 30-metre-tall steam turbine. We also built an adjacent transformer building and a cooling water intake and discharge structure, including the water piping. The steam turbine and generator, providing more than 120 MW of electricity, consists of three sections. The combined section for high- and medium-pressure steam weighs 159 tonnes and was placed on a turbine table.

Special applications

Special aspects of the project involve the following:

• Turbine Table: The turbine table consists of a 2.5-metre-thick concrete slab that rests on a spring assembly on top of concrete columns 13 metres in height. This high-grade concrete structure was poured entirely on-site.
• Cooling water intake and discharge structure: This system consists of several levels that start 10 metres below the water surface. The sheet pile pit with an underwater concrete floor is anchored with tensile anchors. The concrete structure of the intake building itself was poured entirely in situ and the wide-slab floors were produced in our own factory. Three large tail pumps were installed in the intake building. The arrangement includes a fish-return system with filter screens to prevent entrainment of fish by the cooling water setup.
• Cooling water pipe: The glass-reinforced epoxy (GRE) cooling water pipe (2-metre diameter) was installed partly above ground (on prefab concrete sleepers supported by piles) and partly underground. The cooling water intake pipe transports the water from the harbour to the steam turbine to cool it.
• Micro tunnel: A drilled tunnel measuring 160 metres in length and 2.5 metres in diameter at a depth of approximately 11 metres below Middenweg and the adjacent railway track. The cooling water pipe was constructed through this tunnel.