Pipeline Route Selection Research Articles

Optimal Route Selection of Offshore Pipelines Subjected to Submarine Landslides

Background: Offshore lifelines (i.e., pipelines and cables) are usually vulnerable to seabed deformations induced by earthquake-triggered geohazards, such as submarine landslides, soil liquefaction, and tectonic faulting. Since the complete avoidance of all areas characterized by offshore geohazards is not always techno-economically feasible, optimal lifeline route selection is deemed necessary for the safety and serviceability of every such infrastructure, in order to minimize the risk of severe environmental and economic consequences. Objective: The current study presents a decision-support tool for the design of offshore high-pressure gas pipelines, capable of performing: (a) the assessment of submarine landslides along a possible pipeline route (i.e., impact force and landslide width), (b) the assessment of their potential impact on the pipeline (i.e., pipeline strains), and (c) the optimal pipeline route selection. Methods: The advanced capabilities of GIS in lifeline optimal route selection are successfully combined with efficient (semi-)analytical models that realistically assess the response of offshore pipelines when subjected to axial or oblique loading conditions due to a submarine landslide. Results: The efficiency of the smart tool is presented through a case study of an offshore pipeline that is crossing potentially unstable slopes -under static and seismic conditions- in the Adriatic Sea. Five alternative routings are proposed based on the adopted design criteria when crossing the seismically unstable slopes and zones characterized by steep inclination. Conclusion: Provided that sufficient and reliable data are available, the developed decision-support tool can be efficiently used for deriving the potentially optimal route of an offshore pipeline.

Engineering Poster E6: Route selection with artificial intelligence: pseudocode and demonstration of a multi-use artificial intelligence algorithm to perform offshore pipeline, cable and umbilical route selection and optimisation

Poster E6 Routing pipelines, cables and umbilicals in offshore locations represents a key activity with potential impacts for design, installation and operation. Deficient routing may result in (a) increased offshore construction durations (b) requirements for engineered mitigations from geophysical/geotechnical constraints and (c) unforeseen requirements for intervention during operations. Despite this, offshore route selection is restricted to repetitive, inefficient, and iterative processes between draughters, engineers and asset owners. Now, digital technologies enable optimised solutions for cables and pipelines. This paper presents the development and application of a complex routing algorithm using modern software code frameworks. The algorithm serves as an artificial intelligence platform by replicating engineering expertise. This identifies commonly encountered routing constraints such as geophysical features, seabed gradients, existing offshore facilities. Ideal geometric parameters are then determined to minimise route costs. The algorithm structure will be presented in pseudocode, which will define/describe the digital simulation of route selection within the algorithm. This includes sequences such as (a) processing of offshore geotechnical survey data, (b) recreating offshore locales and routes in a data environment, (c) implementation of geospatial intersection detection, (d) 3-dimensional route length optimisation and (e) automated route selection criteria. This replicates the sequence of manual processes undertaken by engineering experts into a digital realm, thus eliminating time-consumption, repetition and human error. Finally, the algorithm will be demonstrated in offshore case studies with challenging conditions such as highly disturbed seabeds and routing obstacles. Thus, engineers in the future developments can better answer the question ‘What is the best route?’. To access the poster click the link on the right. To read the full paper click here

Route selection with artificial intelligence: pseudocode and demonstration of a multi-use artificial intelligence algorithm to perform offshore pipeline, cable and umbilical route selection and optimisation

Routing pipelines, cables and umbilicals in offshore locations represents a key activity with potential impacts for design, installation and operation. Deficient routing may result in (a) increased offshore construction durations (b) requirements for engineered mitigations from geophysical/geotechnical constraints and (c) unforeseen requirements for intervention during operations. Despite this, offshore route selection is restricted to repetitive, inefficient, and iterative processes between draughters, engineers and asset owners. Now, digital technologies enable optimised solutions for cables and pipelines. This paper presents the development and application of a complex routing algorithm using modern software code frameworks. The algorithm serves as an artificial intelligence platform by replicating engineering expertise. This identifies commonly encountered routing constraints such as geophysical features, seabed gradients, existing offshore facilities. Ideal geometric parameters are then determined to minimise route costs. The algorithm structure will be presented in pseudocode, which will define/describe the digital simulation of route selection within the algorithm. This includes sequences such as (a) processing of offshore geotechnical survey data, (b) recreating offshore locales and routes in a data environment, (c) implementation of geospatial intersection detection, (d) 3-dimensional route length optimisation and (e) automated route selection criteria. This replicates the sequence of manual processes undertaken by engineering experts into a digital realm, thus eliminating time-consumption, repetition and human error. Finally, the algorithm will be demonstrated in offshore case studies with challenging conditions such as highly disturbed seabeds and routing obstacles. Thus, engineers in the future developments can better answer the question ‘What is the best route?’.

Application of LIDAR Technology in Oil and Gas Pipeline Route Selection and Optimization

The far reaching advantage of Airborne LiDAR technology in the acquisition of highly dense 3D spatial data for hydraulic modelling and geomorphic studies as well as route analysis, selection and/or optimization etc. cannot be overemphasised. Our aim in this work is to show the significant of extracting coordinates of linear feature from Airborne LiDAR cloud data obtained at low altitude and how these can be used to procure gas pipeline corridor mapping for effective design and implementation. Although the data so obtained can be used invariably to derive various environmental components and derivatives like: DTM, DSM, DEM, TIN, LULC map, contour map, profile map, etc. in accordance with what is demanded or the requirement of the end users. The terrain of study spanning about 27km is (swampy and waterlogged) rendering ground survey methods ineffective. Hence, aerial survey expedition with the aid of Piper Navajo PA-34 airplane coupled with other accompanied equipment were flown. From the point cloud obtained, 1,340 coordinate points were used to generate gas pipeline route alignment, profile and right of way (ROW). Subsequently TIN for the project area was consequently derived. Five route options with total coordinates nodes listing of up to 44 in grand total were extracted and used in best route analysis. Option_5 was selected as the best route after satisfying the conditions imposed for selection.

Evolving a comprehensive geomatics multi-criteria evaluation index model for optimal pipeline route selection

Selection of pipeline routes is a geospatial multi-criteria evaluation problem since it involves the assessment of technical, environmental and safety-related factors that influence pipeline system operations. This study determines the optimal pipeline route for transmission of oil and gas products using the Dangote Refinery Project in Nigeria as a case study. Pertinent route selection factors were identified and structured into the expert feedback model of the Analytical Network Process (ANP) for accurate prioritization. LANDSAT 8 imageries of the study area were processed and classified into various land use and land cover types, which were further modelled in ArcMap 10.2 GIS software for routing analysis. Findings reveal that the most highly prioritized factors for proper route selection were the environmental and geological factors, while the least prioritized was the economic factor. In the end, alternative Route 2 was identified as the optimal route among the four evaluated alternative routes because of its minimum route length, minimum passage length through sensitive settlement areas, and less number of river, stream and existing platforms’ crossings.

Landslide Hazard and Risk Assessment for a Natural Gas Pipeline Project: The Case of the Trans Adriatic Pipeline, Albania Section

The paper focuses on the assessment of landslide hazard and risk along or across the Trans Adriatic Pipeline (TAP) natural gas pipeline project in Albania. TAP is a natural gas pipeline that will transport gas from the Caspian Sea to Europe, crossing Northern Greece and Southern Albania. It has long been recognised that landsliding is a major factor for TAP’s pipeline route selection in mountainous regions, especially the challenging area of central Albania. Experience from similar major pipelines has shown that hazard avoidance is generally the most cost- and time-efficient strategy to minimise the landslide risk since geohazard-related decision-making is usually risk-based. For landslides, the risk profile is expected to be dominated by the upslope expansion of existing landslides, resulting in a loss of ridge crest (where the Right of Way (RoW) is usually located), possibly leading to pipeline rupture. However, it is still possible that new landslides could develop under static and/or seismic conditions, especially on steep ridge flanks along the route. An expert determination approach was adopted to define a consensus for the estimate of the risk (i.e., chance of rupture) for the pipeline at eighty-two (82) identified landslide sites in Albania, to identify “hot spots” along the route, where risk-reduction measures could be prioritised. Ten landslides were characterised as “High Risk”, fifteen as “Medium Risk” and nineteen as “Low Risk”. Following this risk assessment, two large re-routings, as well as several local re-routings, were considered. Further investigation was required to identify the site-specific geotechnical conditions and probable remedial measures in cases where landslides could not be avoided by rerouting.

CO2 Pipeline Design: A Review

There is a need to accurately design pipelines to meet the expected increase in the construction of carbon dioxide (CO2) pipelines after the signing of the Paris Climate Agreement. CO2 pipelines are usually designed with the assumption of a pure CO2 fluid, even though it usually contains impurities, which affect the critical pressure, critical temperature, phase behaviour, and pressure and temperature changes in the pipeline. The design of CO2 pipelines and the calculation of process parameters and fluid properties is not quite accurate with the assumption of pure CO2 fluids. This paper reviews the design of rich CO2 pipelines including pipeline route selection, length and right of way, fluid flow rates and velocities, need for single point-to-point or trunk pipelines, pipeline operating pressures and temperatures, pipeline wall thickness, fluid stream composition, fluid phases, and pipeline diameter and pressure drop calculations. The performance of a hypothetical pipeline was simulated using gPROMS (ver. 4.2.0) and Aspen HYSYS (ver.10.1) and the results of both software were compared to validate equations. Pressure loss due to fluid acceleration was ignored in the development of the diameter/pressure drop equations. Work is ongoing to incorporate fluid acceleration effect and the effects of impurities to improve the current models.

Optimisation of pipeline route in the presence of obstacles based on a least cost path algorithm and laplacian smoothing

Subsea pipeline route design is a crucial task for the offshore oil and gas industry, and the route selected can significantly affect the success or failure of an offshore project. Thus, it is essential to design pipeline routes to be eco-friendly, economical and safe. Obstacle avoidance is one of the main problems that affect pipeline route selection. In this study, we propose a technique for designing an automatic obstacle avoidance. The Laplacian smoothing algorithm was used to make automatically generated pipeline routes fairer. The algorithms were fast and the method was shown to be effective and easy to use in a simple set of case studies.

Fuzzy MCDM-based GIS model for subsea oil pipeline route optimization: An integrated approach

ABSTRACTProper pipeline route selection is an integral component of a typical oil exploration and transportation project. Improperly selected routes could have severe consequences including pipe failures, oil spillage, and environmental disasters. Consequently, technologies like geographic information systems (GIS) are increasingly being used to facilitate the oil pipeline route selection procedure—especially for onshore routing projects. Surprisingly, not much has been documented on the application of GIS to offshore pipeline routing. With recent discoveries on the merits of offshore oil exploration, it is necessary to extend the analytical capabilities of GIS to the unique offshore domain. However, concerns have been raised regarding the limitations of GIS in accurately prioritizing diverse selection criteria in typical multi-criteria decision-making (MCDM) problems like route selection. Consequently, this paper addresses the offshore/subsea pipeline routing constraint using a hybrid decision support system (DSS), which integrates a GIS and fuzzy logic-based approximate reasoning (AR) models for optimal performance. The resultant spatial decision support system (SDSS) was successfully applied to a case study in Malaysia. The AR algorithm calculated the significance level of the multiple criteria using various fuzzy linguistic variables and membership functions. The aggregated priority ranking from different pipeline routing experts showed that the overall influence of the environmental criteria (61.4%) significantly exceeded that of other equally important criteria in the study area. These rankings were inputted into the SDSS to simulate various probable routes. Final results accurately highlighted an optimal route, which places a premium on the protection of environmental features in the subsea study area—in alignment with the preferences of majority of the experts.

Numerical analysis of submarine landslides using a smoothed particle hydrodynamics depth integral model

Submarine landslides can cause severe damage to marine engineering structures. Their sliding velocity and runout distance are two major parameters for quantifying and analyzing the risk of submarine landslides. Currently, commercial calculation programs such as BING have limitations in simulating underwater soil movements. All of these processes can be consistently simulated through a smoothed particle hydrodynamics (SPH) depth integrated model. The basis of the model is a control equation that was developed to take into account the effects of soil consolidation and erosion. In this work, the frictional rheological mode has been used to perform a simulation study of submarine landslides. Time-history curves of the sliding body’s velocity, height, and length under various conditions of water depth, slope gradient, contact friction coefficient, and erosion rate are compared; the maximum sliding distance and velocity are calculated; and patterns of variation are discussed. The findings of this study can provide a reference for disaster warnings and pipeline route selection.

Cost Effective Pipeline Route Selection: An Exact Analytical Solution

Cost Effective Pipeline Route Selection: An Exact Analytical Solution

Determination of Gradient and Curvature Constrained Optimal Paths

Abstract: This article provides an analysis of gradient and curvature constraints on path form and length, with particular reference to road, rail, and pipeline route selection. Initially, we examine the case of a single (global) gradient constraint and a planar surface, with or without boundaries and obstacles. This leads to a consideration of surface representation using rectangular lattices and procedures for determining shortest gradient-constrained paths across such surfaces. Gradient-constrained distance transforms are introduced as a new procedure to enable such optimal paths to be computed, and examples are provided for a range of landform profiles and gradients. Horizontal and vertical curvature constraints are then analyzed and incorporated into final solution paths at subsequent stages of the optimization process. Such paths may then be used as preanalyzed input to detailed cost and engineering models to speed up, and where possible improve, the quality and cost-effectiveness of route selection.

Geographic Information System-based Pipeline Route Selection Process

The Metropolitan Water District of Salt Lake and Sandy recently began construction of the Point of the Mountain Aqueduct. This 1,524 mm (60 in.) diameter pipeline will convey finished water approximately 9 km (12 mi) through mostly developed areas of two communities. Construction of a large-diameter transmission pipeline through heavily developed cities creates many engineering, construction, and public relations challenges. A geographic information system (GIS)-based route selection process was used to provide a rational basis for narrowing hundreds of potential alternatives into one final alignment corridor. The route selection process was based on construction costs as well as important noncost issues. The use of GIS data and GIS analysis software was critical to the success of this project. The GIS software allowed large amounts of pipeline cost-related data to be collected, stored, and documented for each alignment alternative. It was also used to analyze the network of possible alternatives to quickly determine the optimum route between two points based upon construction costs. This allowed for a logical selection and ranking of alternatives, resulting in one final alignment corridor that was acceptable to all of the stakeholders in the project.

Multiple attribute decision making approach to petroleum pipeline route selection

Petroleum pipelines are the nervous system of the oil industry, as this transports crude oil from sources to refineries and petroleum products from refineries to demand points. Therefore, the efficient operation of these pipelines determines the effectiveness of the entire business. Pipeline route selection plays a major role when designing an effective pipeline system, as the health of the pipeline depends on its terrain. The present practice of route selection for petroleum pipelines is governed by factors such as the shortest distance, constructability, minimal effects on the environment, and approachability. Although this reduces capital expenditure, it often proves to be uneconomical when life cycle costing is considered. This study presents a route selection model with the application of an Analytic Hierarchy Process (AHP), a multiple attribute decision making technique. AHP considers all the above factors along with the operability and maintainability factors interactively. This system has been demonstrated here through a case study of pipeline route selection, from an Indian perspective. A cost-benefit comparison of the shortest route (conventionally selected) and optimal route establishes the effectiveness of the model.

Pipeline route selection and ground characterization, Algeria

Purpose of the study A terrain evaluation of a remote area of hyperarid desert in central Algeria was undertaken as part of the frontend engineering design (FEED) studies for a gas field development. The work was part of the identification of suitable route options for a large buried pipeline between the gas fields and the existing pipeline network, some 500 km to the north. The results of the study provided information to support construction costings and preliminary engineering design and construction evaluation of potential geohazards and geotechnical issues, notably trench excavatability and dune mobility, and to help subsequent selection of a specific alignment within the corridor. Techniques used The stages involved in the study are summarized in Figure 1, the work formed part of a broader programme of geological studies to characterize ground conditions along a preferred pipeline route. The basis for the preliminary terrain evaluation was a combination of a desk study review and interpretation of a 1:100 000 scale composite (SPOT and Landsat TM) satellite image of the route corridor (approximately 100 km either side of the proposed route). This evaluation was carried out in the UK and was used to identify locations for a limited number of boreholes and trenches. The results from the boreholes and trenches were used, along with a limited ‘ground truthing’ programme in Algeria, to refine the terrain evaluation and provide typical engineering geological and geomorphological characteristics for each terrain unit. The terrain evaluation involved the identification of generic terrain models (i.e. landscape types) each with a characteristic assemblage of terrain units .

Quantitative Decision Making: A Case of Route Selection for Laying Cross Country Petroleum Pipelines

Selection of route for laying cross country petroleum pipeline is governed by the factors like shortest distance between supply and demand points, constructability, minimum effect on environment, approachability etc. This paper establishes a decision support system (DSS) for pipeline route selection with the application of Analytical Hierarchy Process (AHP), a multi-attribute decision making technique. AHP allows the consideration of all factors in interactive way with the intervention of decision-makers. The application of the model has been demonstrated through a case of pipeline route selection from Indian perspective. The cost- benefit comparison of shortest route (conventionally selected) and optimal route establishes the effectiveness of the model.

The Input of Geomorphology to Oil-related Developments in Shetland and Northeast Scotland

In essence, the input of coastal geomorphology to most oil-related developments at the coastline has been descriptive environmental classification. The uses to which this information has been put are twofold: (1) as background reconnaissance data that are prepared in advance of a development, such as the exploitation of a nearshore drilling lease or a pipeline landfall, and (2) as a basic element in oil spill contingency mapping. A more specialized use of geomorphology has been environmental management advice relating to the construction, restoration, and operation of large-diameter oil and gas pipeline landfalls - all of which make their approach in Northeast Scotland through beach and dune complexes. The techniques consist of traditional morphological mapping considering form, aspect, materials, energy, and estimations of contemporary processes. Implicit in this mapping is the recognition of vulnerability which, in turn, relates closely to habitat recognition. Time is rarely available for process-type measurements. There is also a dependence on existing maps, aerial photographs, and reports. The survey may be done on foot, from boats, fixed-wing aircraft, or helicopters. Airborne video is increasingly being used as a supplementary means of data acquisition. Vertical airborne video used with an image-processing and G.I.S. system shows great potential and more » has been used experimentally for pipeline route selection. « less

Pipeline route selection in an iceberg‐scoured seabed

Abstract This paper deals with the geotechnical considerations in selecting a pipeline route through a seabed subjected to iceberg scouring. Most of the continental shelf of the east coast of Canada has been subjected to ice scouring. Some of the scours are relict, having occurred during periods of lower sea levels, but modern scours can be found from the Grand Banks north to the Arctic. Scours are sporadic on the Grand Banks, where they range in depth from about 1.5 m to 2 m, whereas in places off the coast of Labrador the entire seabed has been reworked by ice scouring and the depths of the scours are greater. Localized pits created by icebergs impacting the seabed are also found over most of the continental shelf area. These are typically less than 5 m deep, but they have been documented up to 10 m in depth. Models that predict ice scour depths have been published over the past several years. These models all assume that the ice is much stronger than the seabed soils. Recent evidence and analysis, however, indicate that ice keels may fail while scouring the seabed, with the result that existing models are not adequate and may tend to overpredict scour depth. This paper deals with the various interacting forces during the scouring process in sloping seabed conditions and includes discussions of the loads that are transmitted to the seabed and the considerations required for constructing and operating pipelines safely in ice‐scoured topography.