20 YEARS DECOMMISSIONING EXPERIENCE - EVOLUTION OF INNOVATIVE SOLUTIONS

Decommissioning is an increasing market sector which has been gradually gathering momentum particularly in the North Sea. The forecast expenditure for removing existing platforms increases with time. This comes together with the increasing complexity of the decommissioning operation. Experience and expertise in this field are key for success. Saipem have been contracted to perform a number of ‘removals’ ranging from subsea templates, subsea pipelines, seabed debris clearance, jacket structures and topside modules. This paper provides an account of our experience gained over the last 20 years performing decommissioning activities. The paper presents the evolution of the techniques developed and focuses in particular on the Lift and Tow method developed after 2004 for a number of subsea applications. Problems always materialise post contract award due to inadequate data. The paper gives a detailed description of the Lift and Tow method along with various innovative techniques developed for this method, ranging from lifting operations supported by motion forecasting through to personnel access onto the structures.

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20 Years Decommissioning Experience - Evolution of Innovative Solutions

10.3940/rina.ijme.2015.a4.344 ◽

2015 ◽

Vol 157 (A4) ◽

pp. 263-274

Keyword(s):

North Sea ◽

Market Sector ◽

The North ◽

Innovative Solutions ◽

Jacket Structures ◽

The North Sea ◽

Subsea Pipelines ◽

Innovative Techniques

"Decommissioning is an increasing market sector which has been gradually gathering momentum particularly in the North Sea. The forecast expenditure for removing existing platforms increases with time. This comes together with the increasing complexity of the decommissioning operation. Experience and expertise in this field are key for success. Saipem have been contracted to perform a number of ‘removals’ ranging from subsea templates, subsea pipelines, seabed debris clearance, jacket structures and topside modules. This paper provides an account of our experience gained over the last 20 years performing decommissioning activities. The paper presents the evolution of the techniques developed and focuses in particular on the Lift and Tow method developed after 2004 for a number of subsea applications. Problems always materialise post contract award due to inadequate data. The paper gives a detailed description of the Lift and Tow method along with various innovative techniques developed for this method, ranging from lifting operations supported by motion forecasting through to personnel access onto the structures."

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Epifauna associated with subsea pipelines in the North Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy196 ◽

2019 ◽

Vol 77 (3) ◽

pp. 1137-1147 ◽

Cited By ~ 2

Author(s):

Nichola C Lacey ◽

Peter Hayes

Keyword(s):

North Sea ◽

Economic Life ◽

Remotely Operated Vehicle ◽

The North ◽

The North Sea ◽

The Uk ◽

Central North Sea ◽

Subsea Pipelines ◽

First Time ◽

Substrate Depth

Abstract An increasing number of pipelines across the UK Continental Shelf are reaching the end of their economic life, resulting in a growing impetus on decommissioning. Implicit to the decommissioning process is the evaluation of the environmental impacts of the different decommissioning options, however little is known regarding the epifauna that interact with these structures. This study utilized industry-collected footage from remotely operated vehicle inspections of pipelines to assess the interactions of benthic epifauna with pipelines, and their associated structures, for the first time. Footage was analysed from across the northern and central North Sea to examine relationships between faunal community compositions and pipelines and their protective coverings. The complex habitat of concrete and Link-lok mattresses had the highest numbers of observable taxa. Differences in community composition were largely due to varying proportions of common epilithic species. There was a weak relationship between pipeline covering type and the species composition of the immediately neighbouring substrate. Depth and latitude were the strongest correlators with the observed community compositions. This study has compiled the first dataset on epifaunal associations with subsea pipelines in the North Sea.

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Introduction to this special section: Case studies: Conventionals

The Leading Edge ◽

10.1190/tle38010010.1 ◽

2019 ◽

Vol 38 (1) ◽

pp. 10-10

Author(s):

Shauna Oppert ◽

Matthew Casey ◽

Kyle T. Spikes

Keyword(s):

Case Studies ◽

North Sea ◽

Reservoir Characterization ◽

Special Section ◽

Data Sets ◽

The North ◽

The North Sea ◽

Well Data ◽

Conventional Systems ◽

Innovative Techniques

Case studies, with a focus on conventional systems, provide insight of seismic and well data sets in terms of characterizing reservoirs with innovative techniques and approaches. This special section contains three such papers from three different regions: offshore Brazil, the North Sea, and the Middle East. Each contribution presents a different geologic problem ranging from siliciclastics to volcanics to carbonates. The challenges faced in each paper were tackled using innovative approaches to reservoir characterization in complex geologic regions.

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