The Stena Impeccable, the tenth of 13 IMOIIMAX tankers ordered from the Chinese shipyard in Guangzhou, China, has been delivered to Stena Bulk. The chemical and product tanker Stena Impeccable has a length of 183 metres, a beam of 32 metres and a deadweight of 50,000 tons. The tanker, which is wholly owned by Stena Bulk, will be operated by Stena Weco and will sail in the company’s logistics system, which currently employs more than 60 vessels.
Images courtesy of Stena Bulk
IMOIIMAX is a further development of an already well-established concept. The innovative technical design was developed by Stena Teknik together with the shipyard Guangzhou Shipbuilding International (GSI). This MR tanker is characterised by extra large cargo flexibility, a high level of safety and low fuel consumption, i.e. 10-20% lower than that of equivalent vessels when sailing at service speed.
Some of the technical solutions that will result in more efficient energy consumption and greater logistic flexibility:
Main engine auto-tuning
With an auto-tuning system, the combustion process in each cylinder is continuously automatically controlled for optimal main engine performance.
More efficient boiler with recovery from multiple heat sources
The vessel is also equipped with a so-called exhaust gas multi-inlet composite boiler, one of the very first to be installed. This boiler not only recovers energy from the main engine’s exhaust gas but also recovers the exhaust gas energy from the auxiliary engines. In addition the boiler has an oil-fired section that can be used in port, thus avoiding the need to run the larger oil-fired boilers to heat the vessel. This, together with main engine auto-tuning and part-load optimization of the auxiliary engines, will result in very efficient energy consumption.
Recovery of propeller energy loss
All propellers lose some of the energy input in the rotating water behind the propeller. With the IMOIIMAX, the energy loss is recovered by fitting a Hub Vortex Absorbing Fin.
Aerodynamic design of the accommodation and bridge
In heavy weather, wind resistance can be significant. The streamlined design of the accommodation and the bridge means that the IMOIIMAX is less affected by wind resistance than other similar vessels.
All cargo tanks are designed to accept any type of cargo the vessel can transport
An IMOIIMAX has 18 cargo tanks. They are all the same and are designed to hold a maximum of 3,000 m3, i.e. the maximum volume permitted for the special-type cargoes the ship can transport.
Effective tank-cleansing system
The flushing system installed ensures that the cleansing process is optimised and since four tanks at a time can be flushed, the time between discharge and loading can be minimized.
Source: Stena Bulk