Wärtsilä Ship Design has unveiled a new Aframax tanker design said to be highly efficient to meet current and upcoming emissions legislation.
The new double hull, single screw crude oil tanker design features a Computational Fluid Dynamics (CFD) optimized hull for less resistance and higher efficiency, with special consideration given to flow lines and pressure distribution along the hull. Meanwhile a cylindrical bow accommodates a range of operational draughts even in rough weather conditions.
The propulsion system is based upon Wärtsilä’s new high performance 2-stroke X62 main engine, with an extra long stroke and low rpm. It also has a minimized physical width to allow a slimmer aft body design, offering further propulsion efficiency.
Compared to currently available main engine options, Wärtsilä says the X62 engine can achieve fuel savings of seven percent on the specific vessel design, and the same vessel speed can be reached using one less cylinder, i.e. six instead of seven cylinders.
For emissions compliance, an integrated Wärtsilä exhaust gas scrubber has been placed on the funnel and connected to the main engine, auxiliary engines and auxiliary boilers. The scrubber effectively reduces sulphur oxide (SOx) emissions, and meets the 0.1 percent sulphur limit even with HFO (Heavy Fuel Oil) having a sulphur content of 3.5 percent.
Meanwhile, a Wärtsilä SCR (Selective Catalytic Reduction) system has been placed before the turbocharger turbine for the main engine. The SCR is a post combustion nitrogen oxides (NOx) abatement system that permits optimised combustion, in terms of efficiency, while reducing NOx emissions by more than 90 percent. The abatement equipment is tuned with the main and auxiliary engines for effective operations across the complete load range and to meet IMO Tier III requirements.
Aframax Tanker Particulars:
Length overall: 253.20 m approx.
Max draught: 15.2 m
Carrying capacity: abt. 117,000t dwt
Net cargo: abt. 134,250m3 in 12 cargo tanks
Loading/discharge rate at the manifold: 9000m3/hr
Bow loading system: 8000m3/hrs
Download: Wärtsilä Aframax Leaflet