Cost-effective tanker configurations for reduced oil outflow

• Main Author: See, Xue Yun
• Other Authors: Dimitrios Konovessis
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/68829
• Institution: Nanyang Technological University

Major shipping accidents resulted in huge amount of oil released into the sea, which damages the marine environment. Thus, conventions were adopted to mitigate oil spills. Despite the conventions, for example, introduction of a double hull tanker, it may still result in oil spills into the sea. Hence, action has to be taken to improve this environmental disaster. This report investigates the potential oil outflow from four types of tankers; Panamax, Aframax, Suezmax and VLCC with respect to the different types of Risk Control Options (RCOs), their corresponding cost of implementation on new built vessels and its cost effectiveness of implementing RCOs. RCOs were introduced to reduce the Potential Loss of Cargo (PLC) during accidents, which may have disastrous effects. The three RCOs that are addressed in this document are the enhanced cargo tank subdivision, increased double bottom height and increased side tank width. An event tree for collision, contact and grounding was developed for the four types of tankers to determine the PLC for each scenario. After implementing the RCO, the “new” PLC was determined to evaluate the reduction of PLC and comparison was made. In addition, the cost of implementing RCOs was evaluated for new built tankers in terms of construction, maintenance and operation cost for the vessel lifespan of 25 years. It is then compared against the CATS criterion to determine whether it is cost effective in implementing the RCOs. The RCO is considered cost effective if the CATS value is less than USD 60,000, whereby its benefit is higher than its implementing cost. The result shows that introducing of longitudinal bulkhead is more effective in reducing PLC as compared to transverse bulkhead. Furthermore, it indicates that the larger the double bottom height and side tank width increased, the more effective it is in reducing PLC. It had proven that RCO 1 is the most effective in reducing PLC and all the RCOs were cost effective to implement on new built tankers.