Aardgasbuffer Zuidwending

Aug 20, 2009 | Amsterdam Unique ‘maintenance tower’ for Zuidwending natural gas buffer

For the Zuidwending natural gas buffer Nuon and Gasunie have installed a specially developed working platform (‘workover rig’) in the first cavern in which the brine is to be replaced by natural gas. The gas pipes will be brought into the caverns (salt cavities) by means of this tower, which is as high as a five-storey apartment block.

This rig is the first anywhere in the world. The rig makes our work better, safer, more sustainable and more efficient’, says natural gas buffer project leader Leo Gitsels. "In addition, the workers can carry out their tasks in a better protected environment."

The rig will remain in use for a long while, because several caverns will have to be prepared consecutively for gas storage. "Given the number of caverns it was worthwhile designing a special installation", Gitsels explains. After the work in one of the caverns is complete, the tower will be dismantled and erected again in the next cavern. The rig will be relocated within one day. The total duration of the work with the rig will be around one year.

Using the rig, the pipes with which the brine is to be extracted from the underground will be replaced by pipes that are suitable for injecting natural gas into and extracting it from the cavern. These gas pipes have to be welded to each other in lengths van approximately 10 metres, reaching an overall length of around 1,000 metres. The total weight of the pipes is about 75 tons. "Which for the equipment in the workover rig, designed to retain a weight of up to 270 tons vast, is a 'simple job'!" says Gitsels.

Zuidwending natural gas buffer

The Zuidwending natural gas buffer is being realised by Zuidwending V.O.F., a partnership firm of Nuon Zuidwending B.V. and Gasunie Zuidwending B.V. The purpose of the buffer is to respond to sudden peak demand for natural gas. To this end, natural gas is stored temporarily in underground salt cavities. This will increase the security of supply for Dutch consumers.

AkzoNobel is responsible for leaching these salt cavities.