الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
An oil tanker inert gas system is one of the most important parts of its design. Fuel oil itself is very difficult to ignite, but its hydrocarbon vapors are explosive when mixed with air in certain concentrations. The purpose of the system is to create an atmosphere inside tanks in which the hydrocarbon oil vapors cannot bum.Chapter one of this thesis has brief introduction to inert gas concept. Chapter two starts with discussing the principles of inert gas system, explosive limits, effect of inert gas on f1ammability and how to use the explosive range diagram. Also chapter two discusses the sources of inert gas system other than diesel engine exhaust gas which has too high oxygen content for use as inert gas, quality of inert gas, components of inert gas and fmally explain the tank atmosphere with inert gas in different condition. Chapter three deals with components of inert gas system such as inert gas plant, scrubber, demister unit, inert gas blower, inert gas regulating valves, deck water seal, inert gas distribution and venting, gas-analyzing, recording and indicating equipment Chapter four has the detailed description for the main operational modes during nonnal operation of oil tankers which frequently take place and are controlled from inert gas operational panel such as inerting of empty tanks, inerting during loading and simultaneous discharge of ballast, inerting duri.ng loaded sea voyage, inerting during discharging and ballasting, inerting during tank cleaning and purging prior to gas freeing and use of the IGS during gas freeing. Chapter five discusses maintenance and testing of different inert gas system components. Chapter six discusses safety considerations with inert gas system as backf10w of cargo gases or cargo from the tanks to the machinery spaces, health hazard, electrostatic hazards and repair of the inert gas system.Chapter seven deals with a case study carried out by OET ORSKE VERITAS (D V) research and innovation to complete Fonnal Safety Assessment (FSA) to assess the effectiveness of inert gas systems (IGS) in reducing the risk associated with cargo tank fire and explosions on oil tankers <20,000dwt. Two different IGSs are considered for two deadweight categories of 4,000-8,000 and 8,000-20,000 .The fmal recommendation is for IGS to be implemented on all new build80,000 20,OOOdwt and product tankers.