Reduction of impacts of oil and gas operations through intelligent maintenance solution

Impacts of oil and gas production operations are always very obvious when there is imbalanced operation, uncontrolled stoppage or catastrophic failure of the system during normal operations. These impacts may range from high flaring and venting of associated petroleum gas, oil release or spillage, equipment damage, fire outbreak to even fatality. Possible causes of imbalanced operations or system failure are categorised into process upset, system degradation, ineffective operation and maintenance procedures and human errors. Effective maintenance strategy integrates major components of the system; people (human factors), operation and maintenance procedures (process) and production plant (technology) to develop an intelligent maintenance solution that is capable of monitoring and detecting fault in the system at incipient stage before operational integrity is compromised. This paper deploys data-based analytics technique to develop condition-based predictive maintenance system to monitor, predict and classify performance of gas processing system. Exhaust gas temperature (EGT) of Gas Turbine Engine (GTE) is one of the operating and control parameters associated with efficiency of the GTE operation. The EGT is measured using several thermocouples, temperature sensors spaced equidistant around the circumference of the exhaust duct of the GTE. Neural network technique of multisensory data fusion is integrated with intelligent maintenance system to monitor performance of GTE, detect fault and classify performance of GTE to optimal, average and abnormal performance

Underwater Central California: A Guide to Saving Your Ocean Heritage

Describes the state of the wildlife and habitats inside the three national marine sanctuaries that stretch along the coast of central California, and identifies key threats to the future of California's coast

Alternative applications of wired drill pipe in drilling and well operations

Master's thesis in Petroleum EngineeringOil and gas companies target to carry out drilling and other well operations in a safe and cost-effective manner with focus on the long-term integrity of the wells. Well operations become more challenging in environments such as depleted formations, extended reach horizontal well and deep-waters. In the recent years, the industry developed new technologies and methods to manage and enhance the efficiency of drilling operations in these environments. However, there are still challenges faced by the industry. For this, the industry developed a wiredpipe (WDP) technology to improve the data quality, quantity as well as speed of transfer. As a result, WDP technology improved the drilling activity significantly. The recently approved plan for development and operation (PDO) has granted Snorre field expansion project (SEP) to Equinor ASA. The field being depleted has planned equal number of injection and production wells, which could have both the pore pressure and formation stress altered. In general, one may expect operational challenges in the field. A total of eight field case studies were conducted on the application of WDP technologies. Based on the lessons learnt, problems associated with the conventional method and the corresponding possible WDP solutions to be utilized in SEP or future field development activities are proposed. Results from the field case study shows that the valued contributions of wiredpipe are faster drilling rate, time-efficient rig operations, risk reduction, enhanced well placement/quality and reduction in mud losses. Results from the possible alterative WDP solution for SEP are with regards to tripping, cementing, wellbore cleanout, perforation, completion and side-tracking operations. The author believes that integrating the solutions will enhance SEP operations, reduce non-productive time and therefore will be cost-effective.submittedVersio

Natural and anthropogenic fluid migration pathways in marine sediments

Fluids are an important agent in nearly all geologic processes that shape the planet Earth. Fluid abundance and composition are governed by flow along permeable beds or natural and anthropogenic structures in the subsurface including faults, wells, and chimneys/pipes. Spatial and temporal variations in fluid flow activity modify total fluxes between geosphere, cryosphere, hydrosphere, and atmosphere. These fluxes have broad implications for geological processes including the formation of natural resources or the occurrence of geohazards including landslides, earthquakes and blowouts. They further play a crucial role for the global carbon cycles and the climate system. A qualitative and quantitative understanding of fluid flow in the subsurface is therefore important to assess the role of fluids in the Earth system and to quantify fluxes from the geosphere into the hydro- and atmosphere. In this Ph.D. thesis I use an integrated, interdisciplinary approach to study natural and anthropogenic fluid migration pathways in marine sediments in the North Sea, the convergent Hikurangi margin, and a section of the ancient Tethys margin which is now exposed near Varna, Bulgaria. The applied methods include conventional 3D seismic, high-resolution 3D seismic, and 2D seismic data as well as hydroacoustic, sedimentological, unmanned aerial vehicle-based photogrammetric and geochemical data. In each of the studied systems, natural and/or anthropogenic fluid migration pathways allow the transport of significant amounts of fluids through marine sediments towards the seafloor. Often the co-existence of multiple pathways enables the fluids to bypass permeability barriers within the Earth’s crust resulting in the formation of structurally complex flow systems. Focused fluid flow along normal faults in the Hikurangi margin likely plays an active role in the subduction drainage system, influences the slope stability and the morphotectonic evolution of the margin. Results from the Eocene Tethys margin show that focused fluid flow in marine sediments is possible in unconsolidated sands if seepage is focused at the top of faulted units and the flux rate is high enough. This stands in contrast to the general assumption that focused fluid flow in marine sediments is limited to low-permeable sediments. In the marine environment the term fluid flow is often used to exclusively refer to the flow of hydrocarbons. However, geochemical data from the North Sea and the Tethys margin indicate that the involved fluids are of different origin including compaction-related dehydration and submarine groundwater discharge. In each of the investigated cases, the temporal and spatial evolution of fluid flow is not fully addressed yet, especially with regard to vertical fluid conduits or the safety of subsurface drilling and storage operations. The results of my thesis highlight that the investigation of fluid migration pathways requires an interdisciplinary approach which may indicate the origin of the fluids, help understand the fluxes of fluids from the geosphere into the hydrosphere and atmosphere of the past, present and future and reveal the resulting consequences for the global carbon cycles and the climate system

Modeling and control of managed pressure drilling operations

The upstream oil and gas industry has witnessed a marked increase in the number of wells drilled in areas with elevated subsurface formation pressures and narrow drilling margins. Managed Pressure Drilling (MPD) techniques have been developed to deal with the challenge of narrow margin wells, offering great promise for improved rig safety and reduced non-productive time. Automation of MPD operations can ensure improved control over wellbore pressure profiles, and there are several commercial solutions currently available. However, these automation efforts seldom take into account the uncertainty and complex dynamics inherent in subsurface environments, and usually assume ideally functioning sensors and actuators, which is rarely the case in real-world drilling operations. This dissertation describes a set of tools and methods that can form the basis for an automation framework for MPD systems, with specific focus on the surface back-pressure technique of MPD. Model-based control algorithms with robust reference tracking, as well as methods for detecting system faults and handling modeling uncertainty, are integrated with a novel multi-phase hydraulics model. The control system and event detection modules are designed using physics-based representations of the drilling processes, as well as models relating uncertain variables in a probabilistic fashion. Validation on high-fidelity simulation models is conducted in order to ascertain the effectiveness of the developed methods.Mechanical Engineerin

Advances in Condition Monitoring, Optimization and Control for Complex Industrial Processes

The book documents 25 papers collected from the Special Issue “Advances in Condition Monitoring, Optimization and Control for Complex Industrial Processes”, highlighting recent research trends in complex industrial processes. The book aims to stimulate the research field and be of benefit to readers from both academic institutes and industrial sectors

Expert-based development of a standard in CO2 sequestration monitoring technology

Bureau of Economic Geolog

Microseismic activity and fluid fault interactions: some results from the Corinth Rift Laboratory (CRL), Greece

International audienceThe Gulf of Corinth, in western-central Greece, is one of the fastest continental rifts in theworld. In its western section near the city of Aigion, the previous work has outlined theexistence of a shallow dipping seismogenic zone between 5 and 12 km. This seismic activityhas been monitored with a network of 12 three-component stations for the period 2000–2007. Three, few months long, seismic swarms have been observed. They mobilize a complexstructural fault system that associates both shallow dipping elements and subvertical structureswith very different azimuths, some of which extend to depths greater than that of the shallowdipping zone. The swarm activity associates intensely active, short crises (a few days) withmore quiescent periods. The long-term growth velocity of the seismically activated domainsis compatible with a fluid diffusion process. Its characteristics are discussed in the context ofthe results from the 1000 m deep AIG10 well that intersects the Aigion Fault at 760 m. Thevertical growth directions of the seismically activated volumes outline two different sources forthe fluid and imply non-steady pressure conditions within the seismic domain. The diffusivityalong the cataclastic zone of the faults is in the order of 1 m2s−1, while faults act as hydraulicbarrier in the direction perpendicular to their strike. If the vertical direction is a principalstress component, the high pore pressure values that must be reached to induce slip on theshallowly dipping planes can result only from transitory dynamic conditions. It is argued thatthe shallow dipping active seismic zone is only local and does not correspond to a 100 kmscale decollement zone. We propose to associate the localization process with deep fluid fluxesthat have progressively modified the local stress field and may be the cause for the quiescenceof the West Heliki Fault presently observed