Control of Major Accident Scenarios in the Åsgard Subsea Compression Project

The world?s first subsea compression system will be installed at the Åsgard field in the Norwegian sea. This will be done to maintain the flow rates of the hydrocarbons above their critical minimum and to maximise reservoir recovery. Because this is the first subsea compression system in the world,...

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Bibliographic Details
Main Author: Berggård, Linn Ingrid
Other Authors: Onshus, Tor Engebret
Format: Master Thesis
Language:English
Published: NTNU 2012
Subjects:
Online Access:http://hdl.handle.net/11250/2400584
Description
Summary:The world?s first subsea compression system will be installed at the Åsgard field in the Norwegian sea. This will be done to maintain the flow rates of the hydrocarbons above their critical minimum and to maximise reservoir recovery. Because this is the first subsea compression system in the world, there are uncertainties as to the risks involved in the installation and operation of the system. This thesis adresses the part of the risk picture which involves major accident risk. An identification and description of the major accident scenarios related to the new subsea equipment at Åsgard has been given. In order to control the risk, Statoil will prepare emergency preparedness plans for the identified major accident scenarios. As a preliminary work, this thesis identifies the different risk reducing measures/barriers which are relevant for each scenario. The overall risk level for the Åsgard Subsea Compression project is low, but operational procedures must be followed in order to keep the risk at this level. The risk related to the different major accident scenarios are all within Statoil?s risk acceptance criteria. The different barriers in place for controlling each major accident scenario has been identified and described. The most important barriers were found to be: ? The process shutdown (PSD) system, which shuts down the production after a significant leak has been detected. ? That the installation and maintenance vessels have a reliable dynamic positioning system. ? Positioning installation or maintenance vessels at a safe distance from subsea hydrocarbon equipment during lifts. ? Relocation of installation or maintenance vessel after a significant subsea leak is detected.