Mammoet was called upon to replace reactors at an active methanol plant in Germany.
TotalEnergies Raffinerie Mitteldeutschland is replacing all reactor units at the methanol plant at a site in Leuna, Germany. A complete shutdown of the plant was not possible, as the production volumes had to be guaranteed. Therefore, only one reactor could be removed and replaced at a time.
A preliminary engineering study carried out by Mammoet concluded that the most efficient solution to replace the reactor unit would be to use a Liebherr LR 1750 crawler crane. It can lift and move a load of 140 tonnes, as well as perform all other lifting operations. This was necessary because, due to space limitations, the pre-assembly and storage area for the components was located approximately 200 m from the installation position.
In order to safely lift the construction module, which was completely fitted with equipment resulting in an offset center of gravity that could not be precisely calculated, Mammoet used its specially developed COGAS winch with four-point rigging, which acted as a balancing system. The operator controls the winch via a remote control and can change the length of the individual rope strands so that the crane hook exactly matches the component`s center of gravity.
By offering everything from a single source, from engineering to crawler crane delivery with rigging to execution with its own personnel and special equipment, Mammoet was able to reduce the number of interfaces and contribute to safe project execution while the plant was in operation.
Firstly, the old reactor and sub-reactor were removed one by one, transported by the crawler crane to the laydown area about 200 m away, and stored there. Special demolition chains were used for rigging. The heavy-duty rigging was then modified, and the new components were lifted into place with the LR 1750.
The new sub-reactor, weighing 120 tonnes, was already stored upright at the pre-assembly area. It was attached, lifted, moved to the plant on the hook of the crawler crane and pivoted into place. The new reactor, weighing 140 tonnes, followed in the same way. Finally, the steel construction module, weighing 100 tonnes, was lifted and moved safely into position using the Mammoet COGAS winch.
