Ostfriesland lies in northern Germany. It is a wide, green land, with beautiful sky, cows, clouds, beaches, and sea. This picturesque spot attracts numerous tourists year after year for relaxation. But that is only one side of this fascinating and attractive landscape. Ostfriesland is also a focal point for one of the most important and cleanest energy carriers: natural gas. For over 30 years, Norwegian gas has been landed, stored, and transported in this region and has proven to be an important economic factor in the area. Natural gas consumption in Germany is now around 100 billion cubic meters per year; about 30 percent of this is imported from gas fields in the North Sea.
Hidden potential used wisely
As a hub for natural gas, a former salt dome in Etzel plays a crucial role. Due to its geological characteristics, this place is perfectly suited for storing raw materials such as natural gas. In the eighties, when Norway and Germany closed a new gas contract and the demands for natural gas in Germany rose, the Etzel storage facility was erected by the Norwegian energy company Statoil. The Etzelfacility is tied to the receiving facilities in Emden and the NETRA pipeline.
After many years of successful gas storage, several energy companies such as E.ON, Statoil, Total and ConocoPhillips partnered with the facility. These companies agreed to expand the facility in 2006. The Etzel gas capacity had to grow from around 500 million to over 1.2 billion cubic meters, which corresponds to the annual consumption of about 400,000 single-family homes. With this capacity, the Etzel gas storage facility makes a decisive contribution to the safe and reliable supply of gas to Germany and throughout Europe in the future.
Heavy units, heavy equipment
Wagenborg was awarded the contract by Statoil to lift and install six adsorbers for the expansion of their part of the plant. These adsorbers all had the same dimensions and measured 13.5 m in length, 4.25m in width, and 4.12 m in height, and each weighs 98.5 tonnes. Besides the adsorbers, additional equipment also had to be installed by Wagenborg. For this special project Wagenborg put a 400 t crawler crane (LR1400) and a 500 t mobile crane into operation. All adsorbers were transported under the hook of the cranes by trailer, after which the two cranes lifted the adsorbers off the trailer. The 500 t mobile crane assisted the crawler crane as a tail crane to position the column from a horizontal position into a vertical position. The LR1400 then lifted the first column onto its foundation. For this lifting job, the crawler crane was mobilized in super lift configuration including lifting gear, like the spreader beams and slings for the columns. After the successful installation of the first adsorber, the other 5 columns followed.
A safe working method
The installation of all adsorbers was executed from the west to the east of the plant. This enabled the crane operator to have a permanent view of the load during the lifting operation. By following this sequence of installing the columns, Wagenborg started with the maximum required super lift counterweight. While working into the southern direction, the super lift counterweight was removed. From this point of view, the most efficient sequence of installation with a minimum risk of damage was chosen.
Again, this was a very impressive project and a great piece of workmanship in which Wagenborg showed her expertise in executing projects on this scale. The entire project was successfully closed within the previously-agreed deadline to the full satisfaction of our customer. The Wagenborg crew can look back on a great project.