For over half a year, engineers, technicians and welders have been constructing the membrane tank at the HuaRun DaDong Dockyard in Shanghai. The “Sajir” has been moored there since the beginning of the month while being prepared for the tank’s installation. A floating crane has now hoisted the tank into the belly of the vessel – which marks one of the most important milestones in the process of converting the “Sajir” to operate using LNG propulsion.
The sun was shining, and there was no wind. The second factor was the most important prerequisite for the successful insertion of the tank in Shanghai, as the floating crane had to hoist both the 1,300-tonne tank and the weight of the carrying device, position them over the part of the ship into which they would be inserted, and then lower them down gently. Special trusses (AKA beams) were used to lift the tank, and these were connected to the crane hook and the tank with 32 wire cables. If there had been wind, it might have led the load to shift, and the tank might have gotten stuck and been deformed.
“It was really a delicate piece of manoeuvring,” says Lutz-Michael Dyck, Senior Director Strategic Asset Projects of Hapag-Lloyd. “The tide was a crucial factor, as well, as we had to make sure that the ship was in a stable condition. At the time of the operation, we had a low tidal range and a low current velocity in the river. So, we were dependent not only on the precise preparation of the tank installation, but especially on external factors.”
Before that, the container guide rails and other fixtures were removed from Hold 9 in order to make room for the tank that would be inserted into it. What’s more, the hold’s floor structure was reinforced to be able to bear the weight of the tank and subsequently the LNG, as well. The tank fills almost the entire width and length of the 40-foot-long bay.
The 35 million USD conversion of the “Sajir” is a key element of Hapag-Lloyd’s sustainability strategy. Using LNG has the potential to reduce CO2 emissions by 15 to 30 percent and sulphur dioxide and particulate matter emissions by more than 90 percent. “With this unique pilot project, we hope to learn for the future and to pave the way for large ships to be retrofitted to use this promising alternative fuel. However, our long-term goal continues to be CO2-neutral shipping operations using synthetic natural gas (SNG),” said Richard von Berlepsch, Managing Director Fleet at Hapag-Lloyd.