310 likes | 568 Views
Project POP&C (Pollution Prevention & Control) A Rational Risk Based Approach For Design And Operation Of Tankers. By Dr Seref AKSU Department of Naval Architecture & Marine Engineering, Universities of Glasgow and Strathclyde. International Workshop on Marine Pollution Control,
E N D
Project POP&C (Pollution Prevention & Control) A Rational Risk Based Approach For Design And Operation Of Tankers By Dr Seref AKSU Department of Naval Architecture & Marine Engineering, Universities of Glasgow and Strathclyde International Workshop on Marine Pollution Control, Athens , 9 June 2006
Presentation Outline • Background • Project Pollution Prevention and Control Objectives Technical Work Areas Some findings / Expected Outcomes / Dissemination Activities • Concluding Remarks
Background to Tanker Safety Stricter International Regulations enacted in the early 90s, improved the tanker industry safety record but societal concern is ever present. Despite these efforts, tanker accidents continue to occur Erika and Prestige incidents have had major political, social and economical implications. As a result, new accelerated phase-out of single hull tankers was introduced. Despite the political and economic importance of these issues, some of the relevant new regulation still tends to be made before incidents have been properly investigated. A proper risk analysis may determine which types of oil tanker pose the highest pollution risk, the relative safety of new tanker designs, or the most appropriate response to an evolving oil pollution incident.
Pollution Prevention and Control - POP&C Project FP6 - Strategic Targeted Research Project (STREP) Start date :January 2004 Duration :3 years Total Budget :2.2 mEuros Consortium consists of 4 Universities 5 Research Institutions 2 Classification Societies 2 Ship yards 2 Ship Operators, and IMO (External)
Consortium Partners Participant name Short name Country INTERTANKO INTERTANKO Norway, UK University of Strathclyde NAME-SSRC UK Bureau Veritas BV France Sirehna SIREHNA France Center of Maritime Technologies CMT Germany National Tech. Univ. of Athens NTUA Greece Gdynia Shipyard GDY Poland Maritime Simulation Rotterdam MSR Netherlands Lloyd’s Register lloyd’s Register UK Navantia NAV Spain SSPA Sweden AB SSPA Sweden Istanbul Technical University ITU Turkey Herbert Software Solutions - EU HSSE UK Souter Shipping (OSG) OSG UK Univ. of Newcastle Upon Tyne UNEW UK
POP&C Objectives • To develop a risk-based methodology to assess the oil spill potential of tankers • To develop a risk-based passive pollution prevention methodology (design and operational lines of defence) • To develop a risk-based active post-accident pollution mitigation and control framework
POP&C – Focus of Application To demonstrate the developed methodology, POP&C consortium agreed to consider AFRAMAX class of tankers. However the methodology is applicable to any type or size of tanker. Therefore, the foregoing discussion will be specific to AFRAMAX class of tankers.
Hazard Identification and Ranking Objective: To identify hazards such as grounding and collision, fire and explosion, structural failure with potential to lead to vessel’s loss of watertight integrity and consequently to pollution and environmental damage. • Compilation and analysis of tanker accidents database • Identification and selection of method(s) suitable for the hazards identification and ranking (techniques such as tabular HAZID, FT/ET analysis, and networks will be considered). • Identification and ranking of relevant hazards • Selection of critical scenarios
Outcomes of HAZID Analysis • An AFRAMAX tanker incidents database was compiled and a comprehensive analysis was performed. • Historical Data Analysis yielded that most important Hazards for Tankers are • Collisions, Contact, Grounding, • Fire, Explosions, and Non-accidental Structural failure • A method utilising both Fault Trees and Event Trees was chosen. Fault Trees and Event Trees were developed for these Hazards • FTs and ETs were populated based on historical data analysis and expert judgment
Example-Grounding Fault Tree Example-Grounding Event Tree
Loss of Damage Stability Objective: To assess the survivability performance of a tanker following breach of watertight integrity of the hull from damage stability and sinkage points of view.
Specific Work Performed/Required • Existing probabilistic survivability assessment models were evaluated for tanker ships • Damage extents for Non-accidental structural failure, Fire, and Explosions were developed. • Population of AFRAMAX tanker fleet configurations were identified • A survivability index (Attained Index of Subdivision - A) is determined for the critical scenarios identified in Hazard Identification and Ranking study • Index A is calibrated against the derived historical risk
Example Damage Scenario Figure : Damage to transverse bulkhead between tanks 2 and 3
Sample Calculations Probability of Survival after damage Oil outflow capacity Aframax Tanker Configuration Data
Structural Reliability Objective: To determine the probability that the hull structural integrity will be lost in the event of the watertight integrity of the hull being breached.
Specific Work Areas of Structural Integrity • Development of specific scenarios for loss of structural integrity • Collision Analysis of single hull and double hull tankers • Residual strength analysis using non-linear FE, • Development of simplified model to account for damage ship structural strength • Assessment of residual structural strength for critical damage scenarios
Overall Passive Pollution Risk Objective: To determine an overall risk index through • Determining consequences of oil outflow, loss of vessel and loss of lives /injuries (and other pertinent costs) in the form of an Index • Developing risk acceptance criteria for each risk element or the combined risk • Developing a Risk-Based Design and Assessment Methodology
Structural Integrity Consequence Analysis Damage survivability RISK Risk = Frequency of Occurrence x Consequence Frequencies of main Hazards i=collision, contact, grounding, fire, explosions, structural failure.
Pollution Prevention Objective: To identify a risk reduction index (or reduction in frequency of events leading to major hazards) if active measures are taken to prevent oil spills through • - Identification of measures to reduce pollution risk by prevention • - Examination of scenarios and developing counter measures • - Identification of generalised scenarios and counter measures.
Pollution Mitigation and Control Objective: To formulate a pollution mitigating and control framework capable to cover adequately oil spill incidents/accidents generated from maritime transport players, namely vessels (tankers) through • identification, ranking and assessing a critical mass of RCOs and PCOs • pinpoint on-board (and nearshore) procedures, processes, policies, guidelines, technologies, innovations and practices, along with human factor aspects • post-accident pollution control activities, such as on-board confinement, safe refuge operations • Risk reduction by reducing consequences
Reduction in frequencies of main Hazards (Prevention) Reduction in consequences Reduction in frequencies of capsize or loss of structural integrity RISK Reduction ΔR = Δ(Pi) x ΔCj
Concluding Remarks • The POP&C project aims to improve the overall safety in transportation of hazardous goods through the development of a risk-based methodology that encompasses ship design and operation (passive and active safety). • In this respect, the focus is twofold: - Existing tankers: to contain risk through identifying/evaluating cost-effective measures of pollution prevention/mitigation by active means. - New designs: to approach design of new tankers rationally byintegrating systematically risk analysis in the design process, addressing prevention/ reduction of pollution risk by passive and active meansby a direct (first-principles) approach.