Decommissioning Guidelines for North Sea Subsea

Wednesday, November 09, 2011
Anthony Onukwu, senior technology analyst from ITF

A new study which aims to inform UK government guidelines on environmentally responsible methods for decommissioning offshore pipeline bundles will be launched in Aberdeen this month. The study was secured with assistance from ITF, the technology facilitator for the global oil and gas industry, following membership support for the project. It will be led by project management and engineering consultancy PDi, with assistance from eight operating companies.
Currently, there is no guidance for the industry on decommissioning pipeline bundles and the study aims to provide a basis for the Department of Energy and Climate Chance (DECC) and stakeholders to assess decommissioning proposals. There are a growing number of North Sea offshore installations due to be decommissioned in the next few years and the topic has been the focus of extensive discussion within the oil and gas industry. More than 470 offshore installations, 10,000 kilometers of pipelines, 15 onshore terminals and around 5,000 wells constitute part of the North Sea infrastructure which will eventually need to be decommissioned in the UK  Continental Shelf (UKCS) at an estimated cost of £20-25 billion. Pipeline bundles allow all of the flow lines, water injection, gas lift, chemical injection and control systems required for a subsea development to be incorporated into one carrier pipe, and offer a number of benefits including protection against external hazards, a reduction in the pipeline corridor and cost savings.
Anthony Onukwu, senior technology analyst from ITF said: “Pipeline bundles may only represent a small percentage of the total length of installed pipeline in the North Sea, but it is essential they are decommissioned in asafe and environmentally responsible manner. “The Department of Energy and Climate Change’s guidelines for the decommissioning of offshore oil and gas installations and pipelines indicate that any new pipeline bundles should be designed for future removal. However, more than 60 pipeline bundles have already been installed in the North Sea, with an estimated combined length of 250km. “Some of these are now approaching decommissioning and currently there are no guidelines on how to do this. This study should be of value to asset owners developing bundle decommissioning programmes and will hopefully provide guidance for DECC and stakeholders when assessing decommissioning proposals.”
A variety of factors, including the type of pipeline and individual circumstances, have to be considered when assessing the options for decommissioning a subsea pipeline. In some cases pipelines may be decommissioned in-situ although complete removal may be the preferred option depending on the circumstances.  Pipeline bundles, however, may present particular issues when it comes to decommissioning which require specific consideration. Graeme MacDougall, operations manager at PDi said: “When it comes to decommissioning, pipeline bundles are substantially different from other pipelines and although they may appear similar to trunk lines, as they have a large diameter and sit on the seabed, unlike trunk lines pipeline bundles are all less than 7.5km long.
“Taking into account their relatively short length, they may seem to have more decommissioning synergies with in-field lines than with trunk lines, but their large diameter generally rules out burial, refloating bundles for recovery poses significant engineering and operational challenges, and cutting it into sections for recovery will involve an extensive subsea intervention campaign and multi-handling of abnormal loads.”  

Maritime Reporter August 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Technology

N-Sea Completes Inaugural System Diving Scope

Inspection, maintenance and repair (IMR) specialist N-Sea has recently completed its inaugural diving scope with the TUP Diving System (Transfer Under Pressure).

Schlumberger Releases 2014 Software Platforms

Schlumberger has released the 2014 versions of its industry leading software platforms. The Petrel* E&P software platform, Techlog* wellbore software platform,

EDGE Facility to Develop, Deliver Security Capabilities

Center in Nova Scotia will focus on rapidly delivering new technologies and capabilities to the Royal Canadian Navy as they transition to future fleet.    General

Offshore

Norvestor to Become PG’s Largest Shareholder

Norvestor VI, L.P., a fund advised by Norvestor Equity AS, announced it has signed an agreement to invest in Ing Per Gjerdrum AS including its subsidiaries PG Hydraulics AS and PG Construction AS.

Crowley Receives Heavy-Lift Deck Barge in Singapore

Crowley Maritime Corporation’s solutions group announced today that it has received the first two of potentially four, new heavy-lift, ballastable deck barges (HDBs)

Signet Transports Second LLOG Rig to GofM

On September 14, five Signet Maritime ASD/Z-Drive tugboats, the SIGNET ENTERPRISE, SIGNET RELIANCE, SIGNET MAGIC, SIGNET WEATHERLY, and SIGNET VOLUNTEER successfully

Consulting

DMR Examines Container Terminal Congestion Issues

Container port congestion has been hitting the headlines recently, but the reasons for it vary widely and in many cases it is only a short term issue. Certain world

IMO Takes Important Step Towards Electronic Certificates

In the future, the IMO member States should accept the use of electronic certificates. This is the request of the Facilitation Committee (FAL) and, hence, the road is paved for less paperwork,

ISS Chile Advising on Oil spill at Quintero Bay

Inchcape Shipping Services (ISS) Chile is advising of an oil spill at Quintero Bay, Nr Valparaiso, Chile, following an incident on Thursday 24th September at

 
 
Maritime Careers / Shipboard Positions Maritime Contracts Maritime Security Navigation Offshore Oil Pipelines Pod Propulsion Port Authority Salvage Sonar
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1339 sec (7 req/sec)