Flow Assurance in Subsea Pipeline Design for Transportation of Petroleum Products

Son Tung Pham; Minh Huy Truong; Ba Tuan Pham

doi:10.4236/ojce.2017.72021

Flow Assurance in Subsea Pipeline Design - A Case Study of Ghana’s Jubilee and TEN Fields

Ghana Mining Journal ◽

10.4314/gm.v19i1.9 ◽

2019 ◽

Vol 19 (1) ◽

pp. 72-85

Author(s):

S. A. Marfo ◽

P. Opoku Appau ◽

J. Acquah ◽

E. M. Amarfio

Keyword(s):

Flow Rate ◽

Hydrate Formation ◽

Flow Assurance ◽

Processing Plant ◽

Subsea Pipeline ◽

Gas Processing ◽

Parallel Pipeline ◽

Exploration And Production ◽

Insulation Thickness ◽

Pipeline Design

The increasing exploration and production activities in the offshore Cape Three Point Blocks of Ghana have led to the discovery and development of gas condensate fields in addition to the oil fields which produce significant amount of condensate gas. These discoveries require pipelines to transport the fluids avoiding hydrates and wax formation. This paper focuses on subsea pipeline design using Pipesim software that addresses flow assurance problems associated with transporting condensate gas from the Jubilee and TEN Fields to the Atuabo Gas Processing Plant. It also considered an alternate design that eliminates the need for capacity increase of flowlines for the futuristic highest projected flow rates in 2030. The design comprises of two risers and two flowlines. Hydrate formation temperature was determined to be 72.5 ˚F at a pressure of 3 000 psig. The insulation thickness for flowlines 1 and 2 were determined to be 1.5 in. and 2 in. respectively. The pipe size for flowlines 1 and 2 were determined to be 12 in. and 14 in. respectively. The maximum designed flow rate was determined to be 150 MMSCFD. To meet the highest projected flow rate of 700 MMSCFD in the year 2030 at the processing plant, a 16 in. ID pipeline of 44 km length was placed parallel to the 12 in. ID flowline 1. This parallel pipeline increased the designed flow rate by approximately 4.7 times (705 MMSCFD). The alternate design employs 18 in. and 20 in. ID pipes for flowlines 1 and 2 respectively. Keywords: Condensate Gas; Flowline; Flow Assurance; Hydrate; Pipesim

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Case Studies Highlighting Rapid Repair Methods of Pressurised Pipelines Damaged by Anchors

Volume 2: Pipeline Safety Management Systems; Project Management, Design, Construction, and Environmental Issues; Strain Based Design; Risk and Reliability; Northern Offshore and Production Pipelines ◽

10.1115/ipc2018-78105 ◽

2018 ◽

Author(s):

Dale Millward

Keyword(s):

Case Studies ◽

Health And Safety ◽

Cost Effective ◽

Pipeline System ◽

Subsea Pipeline ◽

Damage Scenarios ◽

Fail Safe ◽

Subsea Pipelines ◽

Marine Vessels ◽

Pipeline Design

Effective pipeline design and regular maintenance can assist in prolonging the lifespan of subsea pipelines, however the presence of marine vessels can significantly increase the risk of pipeline damage from anchor hazards. As noted in the Health and Safety Executive – Guideline for Pipeline Operators on Pipeline Anchor Hazards 2009. “Anchor hazards can pose a significant threat to pipeline integrity. The consequences of damage to a pipeline could include loss of life, injury, fire, explosion, loss of buoyancy around a vessel and major pollution”. This paper will describe state of the art pipeline isolation tooling that enables safe modification of pressurised subsea pipelines. Double Block and Bleed (DBB) isolation tools have been utilised to greatly reduce downtime, increase safety and maximise unplanned maintenance, providing cost-effective solutions to the end user. High integrity isolation methods, in compliance with international subsea system intervention and isolation guidelines (IMCA D 044 / IMCA D 006), that enable piggable and unpiggable pipeline systems to be isolated before any breaking of containment, will also be explained. This paper will discuss subsea pipeline damage scenarios and repair options available to ensure a safe isolation of the pipeline and contents in the event of an incident DNV GL type approved isolation technology enables the installation of a fail-safe, DBB isolation in the event of a midline defect. The paper will conclude with case studies highlighting challenging subsea pipeline repair scenarios successfully executed, without depressurising the entire pipeline system, and in some cases without shutting down or interrupting production.

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Subsea Gas Well Late Life Restart Lesson Learned: Failure Analysis and Operating Strategy

10.2118/208620-ms ◽

2021 ◽

Author(s):

Song Wang ◽

Lawrence Khin Leong Lau ◽

Wu Jun Tong ◽

Kun An ◽

Jiang Nan Duan ◽

...

Keyword(s):

Failure Analysis ◽

Late Life ◽

Flow Assurance ◽

Gas Well ◽

Subsea Pipeline ◽

Operating Strategy ◽

Root Cause ◽

Financial Impacts ◽

Transient Multiphase Flow

Abstract This paper elucidates the importance of flow assurance transient multiphase modelling to ensure uninterrupted late life productions. This is discussed in details through the case study of shut-in and restart scenarios of a subsea gas well (namely Well A) located in South China Sea region. There were two wells (Well A and Well B) producing steadily prior to asset shut-in, as a requirement for subsea pipeline maintenance works. However, it was found that Well A failed to restart while Well B successfully resumed production after the pipeline maintenance works. Flow assurance team is called in order to understand the root cause of the failed re-start of Well A to avoid similar failure for Well B and other wells in this region. Through failure analysis of Well A, key root cause is identified and associated operating strategy is proposed for use for Well B, which is producing through the same subsea infrastructure. Transient multiphase flow assurance model including subsea Well A, subsea Well B, associated spools, subsea pipeline and subsea riser is developed and fully benchmarked against field data to ensure realistic thermohydraulics representations of the actual asset. Simulation result shows failed restart of Well A and successful restart of Well B, which fully matched with field observations. Further analysis reveals that liquid column accumulated within the wellbore of Well A associates with extra hydrostatic head which caused failed well restart. Through a series of sensitivity analysis, the possibility of successful Well A restart is investigated by manipulating topsides back pressure settings and production flowrates prior to shut-in. These serve as a methodology to systematically analyze such transient scenario and to provide basis for field operating strategy. The analysis and strategy proposed through detailed modelling and simulation serves as valuable guidance for Well B, should shut-in and restart operation is required. This study shows the importance of modelling prior to late life field operations, in order to avoid similar failed well restart, which causes significant production and financial impacts.

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Overpressure Protections in Liquid Pipeline Hydraulic Design

Volume 3: Operations, Monitoring and Maintenance; Materials and Joining ◽

10.1115/ipc2016-64687 ◽

2016 ◽

Author(s):

Alan X. L. Zhou ◽

David Yu ◽

Victor Cabrejo

Keyword(s):

New Technologies ◽

Pressure Control ◽

Petroleum Products ◽

Integrated System ◽

Operating Conditions ◽

Design Stage ◽

Pipeline System ◽

Protection Measures ◽

Pipeline Systems ◽

Pipeline Design

Continuous economic development demands safe and efficient means of transporting large quantities of crude oil and other hydrocarbon products over vast extensions of land. Such transportation provides critical links between organizations and companies, permitting goods to flow between their facilities. Operation safety is paramount in transporting petroleum products in the pipeline industry. Safety can affect the performance and economics of pipeline system. Pipeline design codes also evolve as new technologies become available and management principles and practices improve. While effective operation safety requires well-trained operators, adequate operational procedures and compliance with regulatory requirements, the best way to ensure process safety is to implement safety systems during the design stage of pipeline system. Pressure controls and overpressure protection measures are important components of a modern pipeline system. This system is intended to provide reliable control and prevent catastrophic failure of the transport system due to overpressure conditions that can occur under abnormal operating conditions. This paper discusses common pressure surge events, options of overpressure protection strategies in pipeline design and ideas on transient hydraulic analyses for pipeline systems. Different overpressure protection techniques considered herein are based on pressure relief, pressure control systems, equipment operation characteristics, and integrated system wide approach outlining complete pressure control and overpressure protection architecture for pipeline systems. Although the analyses presented in this paper are applicable across a broad range of operating conditions and different pipeline system designs, it is not possible to cover all situations and different pipeline systems have their own unique solutions. As such, sound engineering judgment and engineering principles should always be applied in any engineering design.

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Subsea Pipeline Design Automation Using Digital Field Twin

10.2118/197394-ms ◽

2019 ◽

Cited By ~ 1

Author(s):

Subrata Bhowmik ◽

Gautier Noiray ◽

Harit Naik

Keyword(s):

Design Automation ◽

Subsea Pipeline ◽

Pipeline Design

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Development of a simulation method for the subsea production system

Journal of Computational Design and Engineering ◽

10.7315/jcde.2014.017 ◽

2014 ◽

Vol 1 (3) ◽

pp. 173-186 ◽

Cited By ~ 3

Author(s):

Jong Hun Woo ◽

Jong Ho Nam ◽

Kwang Hee Ko

Keyword(s):

Production System ◽

Deep Sea ◽

System Integration ◽

Integrated Design ◽

Flow Assurance ◽

Production Plant ◽

Simulation Technology ◽

Subsea Pipeline ◽

Pipeline Network ◽

Production Processes

Abstract The failure of a subsea production plant could induce fatal hazards and enormous loss to human lives, environments, and properties. Thus, for securing integrated design safety, core source technologies include subsea system integration that has high safety and reliability and a technique for the subsea flow assurance of subsea production plant and subsea pipeline network fluids. The evaluation of subsea flow assurance needs to be performed considering the performance of a subsea production plant, reservoir production characteristics, and the flow characteristics of multiphase fluids. A subsea production plant is installed in the deep sea, and thus is exposed to a high-pressure/low-temperature environment. Accordingly, hydrates could be formed inside a subsea production plant or within a subsea pipeline network. These hydrates could induce serious damages by blocking the flow of subsea fluids. In this study, a simulation technology, which can visualize the system configuration of subsea production processes and can simulate stable flow of fluids, was introduced. Most existing subsea simulations have performed the analysis of dynamic behaviors for the installation of subsea facilities or the flow analysis of multiphase flow within pipes. The above studies occupy extensive research areas of the subsea field. In this study, with the goal of simulating the configuration of an entire deep sea production system compared to existing studies, a DES-based simulation technology, which can logically simulate oil production processes in the deep sea, was analyzed, and an implementation example of a simplified case was introduced.

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