bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel System for Mitigating Sand Production Using Surface Modified Nanoparticle
Authors: Kalgaonkar Rajendra Arunkumar , Chang Fakuen
Published: November 2020

Sanding in hydrocarbon producing and water injection wells has been a severe problem in unconsolidated formations. Many technical solutions have been evaluated by the industry. These solutions encompass mechanical sand exclusion methods such as screen, gravel packing, and frac and pack. Various production and completion practices such as controlling the production rate and following specific well completion guidelines to minimize sand production have failed to provide satisfactory returns. Several limitations such as screen plugging and high costs associated with deploying expandable screens make the current mechanical sand control practices more expensive. With both cost and treatment effectiveness in mind, chemical sand consolidation could present the most cost effective remediation and prevention opportunity. Additionally this would also allow the wellbore to be free of tools, screens and pack sands.

In this paper we describe the development of a unique chemistry for mitigating sand production in unconsolidated formations. This chemistry involves using cationically-modified nanoparticles that can self-assemble over loose formation sand to form a layer of consolidating material thus preventing any unwanted sand production. The new consolidation treatment material consists of colloidal nanoparticles modified using a cationic modifier and oligomeric activator that is initially low viscosity fluid. The fluid has high affinity to the solid surface therefore less prone to build up in the pore space. Once cured at reservoir temperature it forms a thin layer of hard gel around the surface of the sand particles, thus cementing the sand grains together at the same time maintaining open porosity to ensure easy flow of hydrocarbons and injected water.

The ability of the new fluid to consolidate loose sand and at the same time maintain good permeability was investigated. Various oligomeric activators were studied with particular focus on effect of concentration temperature and shear. The ability of the cationic modified nanoparticles to self-assemble around unconsolidated sand and eventually cure to form a consolidated sand pack was investigated. Regain permeability studies showed excellent regain permeability of the consolidated sand pack. It was also shown that the new sand control fluid system provides a controllable curing time, thus avoiding any premature setting of the nanoparticles in the wellbore.

The novelty of the newly developed sand consolidation system is its ability to self-assemble around unconsolidated sand and eventually cure to form a consolidated sand pack while maintaining good permeability.
Application of Compressive Seismic Imaging Technology for Multi Component Ocean Bottom Nodes Seismic Survey Acquisition in K Field, Sabah Offshore and Reconstruction of Multi Component Data
Authors: Abdul Rahim Abdul Aziz , Zainal Nur Fitri , Li Chengbo , Mosher Chuck C. , Janiszewski Frank D.
Published: November 2020

An illumination forward modelling feasibility study conducted in year 2017 over K-field, Offshore Sabah has demonstrated multi-component Ocean Bottom Node (OBN) seismic as a viable method in achieving the subsurface objectives particularly utilising mode-converted shear waves (Ps) that will not be affected by the gas overburden; thus, allowing imaging the structure and characterizing the reservoir underneath it. The seismic survey design was optimized further through Compressive Seismic Imaging (CSI) where seismic sampling is unregularized to improve imaging based on the increase in fold, trace density and bandwidth while optimizing cost through reduced sail line kilometers. The acquired data was then reconstructed to enables denser sampling and higher unaliased bandwith.
Integration of Casing Wear Simulation in Well Design and Casing Stress Analysis for Lateral Wells
Authors: Rosland Habil Akram , Tengku Majid Tengku Khairi , Rosli Azlesham
Published: November 2020

A casing wear assessment was implemented as part of the workflow and methodologies for an operator well design process to better anticipate the critical failure mode of a tubular string. Because the reduction in tubular string wall thickness as a result of drilling and workover operations has been an ongoing concern within oil and gas field development, casing wear modeling with a workflow to accurately predict wear and minimize uncertainties is vital to maintaining well integrity throughout its lifespan with minimal or zero intervention. Because of multiple high-angle lateral branches drilled in lateral wells, the wear factor should be understood while managing casing wear. Wellbore and drillstring geometry can incur high lateral loads on tool strings and production casing, causing possible excessive casing wear. This wear reduces both burst and collapse ratings of the casing and can wear through the casing, resulting in costly remedial intervention measures for mitigation.

This paper provides an integral insight for production casing wear focusing on a lateral well simulations study of the underlying wear factors ranging from the base case to the worst case. This enables a proper assessment in the well design by means of casing integrity, particularly for multilaterals and deep and/or long horizontal wells. A simulation and detailed workflow on how to incorporate its results into a multilateral/highly deviated casing design and stress analysis are discussed, thus providing an integration process resulting in improved anticipation of the critical failure mode for the investigated tubular string for this type of well.
Artificial Intelligence Assisted Production Forecasting and Well Surveillance
Authors: Masini Shashipal Reddy , Goswami Shubham , Kumar Aditya , Chennakrishnan Balaji , Baghele Abhishek
Published: November 2020

In oil and gas, Production forecasting is the most vital process required for all the operational and investment decisions. The basis for any project-based resource estimation is a good production forecast. The objective of this paper is to demonstrate assisted production forecasting from the real-time data using AI (Artificial Intelligence) Techniques.

Decline curve analysis is one of the most used production forecasting methodology. Conventional Production Forecasting involves anomaly removal and applying best method for DCA (decline curve analysis). These processes are combined and automated Using Big data and AI techniques, in this method. The algorithm used clustering techniques like isolation forest and density-based clustering to automatically remove the anomalies and later uses neural network / conventional curve fitting (depending upon data frequency) for production forecasting. It also used LSTM (Long Short-term memory cells algorithm) neural network to predict the flowing bottom-hole pressure with the rates forecasted using automated production forecasting. This in-turn was used along with VFP (Vertical Flow Performance) curves of the well to assess the well ceasure date under existing condition. The algorithm also has a module to recommend the decline rates of workover wells based on the similar past events by using unsupervised clustering techniques.

The algorithm removed the anomalies data and perform production forecasting in a scalable manner. The actual and calculated EURs were matching very closely (very less root mean square error and a maximum deviation of 8%).

This approach is useful to debottleneck the processes involved in production forecasting like identifying the rate changes, production forecasting and FBHP prediction. This information can be coupled with an interactive dashboard to support quick diagnostics, easy interpretations and prompt business decisions.
First Successful Utilisation of High Density Micronised Ilmenite in South East Asia
Authors: A Razak M Solehuddin , Ezani Farah Shakina
Published: November 2020

The objective of this paper is to share the Operator's first experience in utilizing ilmenite in an offshore HPHT well as part of a low cost well initiative and the value obtained by utilization of such a weighting agent in particular towards lowering ECD. After extensive testing micronized ilmenite was used as the weighting agent for the synthetic based drilling fluid (SBM) for the B1 well. This well was classified as high complexity with a narrow margin window and with predicted maximum bottom hole pressure of 12,013 psi at 3,990 m TVDDF.

Extensive laboratory testing was conducted to determine the optimum formulation for a 16 ppg SBM. Part of the methodology in the testing was conducting rheology comparisons between various weighting agents, manganese tetraoxide, barite and micronized ilmenite. The subsequent results were then run through hydraulics simulations to determine the best formulation for optimized hydraulics. Additional testing was conducted to determine the overall stability of the system including conducting static sag tests with a similar duration to the planned wireline logging operation.

The primary drivers for using this fluid were to reduce ECD in a narrow margin environment and facilitate the taking of good wireline logs by providing optimum hole conditions without any sag. The micronized ilmenite system successfully achieved a similar rheology to manganese tetraoxide with low PV's of less than 50 cP at 17 ppg and a sag index of less than 0.52. These properties were at an OWR of 80:20. This led to both the successful drilling of the well and completing the required wireline logging with no fluids related NPT or issues related to sag. During logging, the mud was static for 5 days without problems. The mud weight of 17 ppg was the highest density, at that time, at which the micronized ilmenite system had been used.
Pulsed–Neutron Log Design for Uncertain Water Salinity Reservoirs in an Oil Producer Offshore
Authors: Tao Bin , Zhou Jiheng , Wu Ke , Zhang Zhongqing
Published: November 2020

When an offshore oilfield enters its secondary development stage, the formation residual oil saturation is the crucial information for development planning. Pulsed-neutron logs can accomplish the task of residual oil saturation investigation in cased hole. Building on the various types of nuclear reactions between neutrons and formation, multiple pulse neutron logging modes were developed and are applied in different logging environment. How to choose the most appropriate log mode to improve work efficiency is particularly important for offshore operations.

The capture cross-section log (SIGMA) is the best choice in high water salinity reservoirs. It can be recorded with relatively faster speed and need single pass only, saving lots of operation time. But sometimes the formation behind casing may be polluted by the low-salinity water injected during the past oilfield development, the uncertainties of the water salinity always act an important role effecting the accuracy of interpretation results. The carbon/ oxygen ratio log (C/O) can overcome the water salinity problem, because it is salinity-independent log. However, due to the measurement physics, a C/O log usually requires multiple passes with lower logging speeds, cost significant amounts of operation time.

This paper introduces a novel pulsed-neutron log design that was successfully practiced in North Asia, where it took the advantages from both Sigma and C/O log modes to efficiently overcome the challenges of residual oil investigation in an injection polluted formation. The core method of this log design is "C/O calibrated Sigma". We use C/O log results to calibrate the formation sigma water, then apply it to calculate the water saturation of full interval. Field engineer log a short interval in C/O mode with multiple passes. Then log only a single pass with full target formation in SIGMA mode. Once the geoscientist received the data, firstly process C/O data to work out the water saturation of that short interval. Secondly, use the saturation result of C/O along with SIGMA log data to inverse-calculate the formation water sigma. Finally, apply the water sigma to calculate the water saturation of full interval.

By applying this methodology, the calibrated formation water salinity was calculated and proved to be lower than the original formation water. The full scope formation water saturation was successfully determined within an acceptable operating time (6 hours), compared with conducting the C/O log across the full interval which required more than 18 hours, increased the offshore operations efficiency as well as minimized the interpretation result uncertainties.
A Truly Multi Cycle, Remotely Activated Barrier Valve Boosts Reliability in Subsea Applications
Authors: Croucamp Leandre , Munro Christopher Robert , Murdoch Euan Martin
Published: November 2020

The reliability of subsurface barrier valves has long been an industry problem. This can lead to costly interventions, especially apparent in deep-water subsea markets. This paper describes the world's first deployment of multicycle barrier valves in 2 subsea wells in Australia that uses innovative methods of both remote activation and triggering, that have been previously unavailable on the market, and attain a step change in reliability.

The remote activated barrier valves were deployed as part of a subsea gravel pack system. They were initially run in hole (RIH) open as part of the lower completion, then closed mechanically. The valve was subsequently opened via Radio Frequency Identification (RFID) tags and then closed again mechanically to allow the running of the upper completion. Frequency modulated pressure cycles were applied to the well to open the valve and allow the well to flow.

The valve functioned exactly as planned, and it was demonstrated that it could be closed multiple times on a semi-sub vessel. The valve was then opened via RFID tags conveyed on wash pipe. This is a much more reliable method when in high debris environments. The valve was opened for the final time via frequency modulated pressure cycles. These are better able to be transmitted through debris and are not affected by other hydraulic events in the well.

The hydraulic pump that is used to actuate the tool provides a constant force directly to the ball valve mechanism and is not subject to failures over time like existing gas charges, ratchet mechanisms or springs. The RFID, Mechanical or pressure cycles used to trigger the valve offer a huge increase in operational flexibility that have never been able to be realized with existing technologies.
Application of Intelligent Sliding Sleeves to Improve Reservoir Management, Operation Efficiency and Well Economics
Authors: Wei Ping , Zeng Fanqian , Wang Kai
Published: November 2020

The sliding sleeve has been widely used in upper completions as a useful flow management device to enable selective communications between the production tubing and the annulus. Traditional sliding sleeves are mechanically operated by standard wireline method, which not only results in non-productive time and potential operational risks but also restricts sliding sleeve applicable in vertical wellbores only.

To overcome the limitations, this paper introduced an innovative Hydraulic Controlled Sliding Sleeve (HCSS), which eliminates interventions with conventional wireline shifting tools. HCSS offers instant open/close operation by surface controlled hydraulic pressure through a single control line. HCSS features unique advantages over mechanical sliding sleeves, by its operational simplicity, independence on wireline units, and applicability in deviated wells and horizontal wells. The application of HCSS could save non-productive time, reduce operational risks and improve operational efficiency and economics.

This paper will give a comprehensive demonstration of HCSS and illustrate the working principle in detail. Unique features and capabilities over traditional sleeves will be discussed explicitly. HCSS will be opened by applying hydraulic pressure from the surface control unit to activate the movement of the inner sleeve, and it will be closed simply by releasing the pressure, which will allow the inner sleeve to return to its original position. In the case of hydraulic control failure, HCSS also equipped with a secondary open/close mechanism by the special shift tools operated by coiled tubing. The authors conducted two representative case studies of HCSS application in offshore upper completion in Bohai bay in China to further highlight the improvement of operational efficiency and well economics.
Artificial Neural Network Surrogate Reservoir Proxy Modeling for Generating Pressure and Gas Saturation at the Grid–Block Level in Shale Gas Reservoirs
Authors: Maula Azman , Rofieq Shodiq , Sabila Tsani , Lestariono Yuli
Published: November 2020

Core reservoir management studies involving sensitivity, history matching, predictive forecast, optimization and uncertainty tasks require hundreds of numerical simulations. To enhance reservoir descriptions; more data acquisition, computational power and complex models are engineered. This creates an unstainable time consuming, computationally expensive cyclical process to which the industry could not yet realize the true potential of such full-field reservoir models [1].

In line with the upcoming fourth paradigm shift involving data driven science, this study aims to use data mining and artificial intelligence to investigate the conceptual framework, development and feasibility of data-driven approach in Artificial Neural Network based Grid-block Surrogate Reservoir Model (GSRM) Smart Proxy. The Smart Proxy model is applied for unconventional shale gas reservoirs with dynamic property response prediction output of grid-block pressure and gas saturation.

The GSRM Smart Proxy was developed based on data mining and artificial intelligence technique using VBA programming language in Excel and MATLAB Neural Network Toolbox. Validation of the Smart Proxy model is conducted against commercial simulator unconventional benchmark model in Computer Modelling Group (CMG). Data gathering of the benchmark numerical shale gas model was first conducted followed by the sensitivity analysis of parameters. Most sensitive parameters were identified and brought forward to the design of experiment task to generate a total of 58 datasets covering the solution space. The datasets were run, and simulator output results of grid gas saturation were extracted and deconvoluted using Excel VBA program. The scenarios database is then utilized in MATLAB Neural Network Toolbox to construct GSRM Smart Proxy through data science tasks such as feature engineering, neural net architecture design, model training, validation and testing.

Results of the developed GSRM Smart Proxy test predictions of grid-block pressure and grid-block gas saturation neural network models were compared to have a sufficiently acceptable match accuracy and validated to the benchmark numerical reservoir model solution with R2of 0.947 and R2of 0.934 respectively, also with MSE of 2.52E-03 and MSE of 2.55E-03 respectively for the test sets. GSRM outputs are found to be obtained with minimal computation power and runtime (seconds).
Fatigue Analysis of Flexible Riser Using Hybrid Machine Learning
Authors: Bhowmik Subrata
Published: November 2020

This paper presents a novel hybrid machine learning methodology for evaluating the fatigue life of a flexible riser on long term environmental loading. Flexible risers are multi-layered structures made of several layers including pressure armour and tensile armour layers, out of which tensile armour layer is more prone to fatigue damage of flexible riser on long term environmental loading. The evaluation of stresses on the tensile armour layer is a complicated method due to friction acting between the internal layers. The friction coefficients between layers are calculated using analytical method proposed by Saevik [1] and used as a training data set for the Artificial Neural Network(ANN) model. Hybrid Machine Learning (Back Propagation Neural Network + Generic Algorithm) is used in the proposed fatigue damage estimation method.

Global fatigue analysis of a flexible riser has been performed with environmental loading. The effective tension and bending moments are evaluated in the global analysis and used as inputs to the proposed Hybrid Machine Learning model to calculate the stresses in the tensile armour layer. The fatigue life of the riser based on the predicted stresses is computed using the rainflow counting method. A case study is described for a 12" diameter flexible riser with from turret moored FPSO with typical north-sea environmental loading is applied for demonstrating the methodology.

The proposed hybrid method is a nonlinear parametric model where the parameters are optimised based on Genetic Algorithm based ANN model and the to predict stress on tensile armour from two primary input; bending moment and effective tension. The hybrid model is quite useful to evaluate the fatigue damage prediction on tensile armour layer. Comparing the fatigue life calculated from the proposed hybrid method and the analytical approach focuses on a nonlinear, friction coefficient dependent model [1], it is clearly visible that there is good agreement between both results. The proposed method is a Machine Learning based predictive model and can be used as an alternative tool for predicting fatigue damage in the flexible riser
Advanced Pipeline Isolation Solutions to Enhance Valve Change Outs Minimizing Downtime
Authors: Lie Rolf Gunnar , Anderson Gary , Liao Jane , Rong Chang Roger Ren
Published: November 2020

In order to stabilize the supply of gas to its domestic market, China Petroleum Corporation (CPC), Taiwan, the sole natural gas supplier, has established an integrated gas distribution network in the western part of Taiwan with an inland transmission trunk line, offshore transmission trunk line and regional transmission loops. CPC's gas pipeline planning is based on the concept of forming a ring-shaped gas transmission network along the island. The 36-inch diameter Yung-An to Tung-Hsiao offshore pipeline (Figure 1) is the largest and longest transmission pipeline in the entire network, delivering gas from southern Taiwan to northern Taiwan, where the dominant gas market is located. It was discovered that the emergency shutdown valves (ESDV) at both the Yung-An LNG terminal and the Tung-Hsiao gas transfer station, which are connected by a 237.7-km (147.7-mi), 36-inch offshore pipeline, required replacement or maintenance so that

CPC could resume operational pigging of the pipeline and carry out regular in-line inspection (ILI), as required by regulations.

Methods, Procedures, Process: For this project, CPC decided to apply advanced isolation technology known as SmartPlug® in-line isolation and hot tapping and STOPPLE® isolation technology to isolate the pipeline pressure at 60 bar (870 psi) before executing the repair work. The isolation enabled the operator to avoid depressurizing and purging their entire 237.7-km (147.7-mile) gas export pipeline while mitigating safety concerns associated with defective ESDVs and corroded components. This paper describes the steps taken from planning, to site visit and engineering, to safely and successfully executing the isolation.

Novel/Additive Information: Continued operation with defective pipeline isolation valves and corroded components would have been highly undesirable and would have caused many safety concerns for the pipeline's owner. Using SmartPlug with hot tapping and STOPPLE technology allowed the operator to avoid depressurizing and purging the entire gas export line, which would have meant flaring venting a large quantity of natural gas, a huge business opportunity loss and an event of significant environmental impact. It would have taken several days to fully depressurize and flare the entire pipeline, and several more days to reintroduce hydrocarbons into the pipeline before gas deliveries could resume. The project schedule allowed for only seven days of work during the 2019 Chinese New Year holidays, when energy consumption in Taiwan is lower than usual. While the 36-inch pipeline was isolated, CPC also took the opportunity to replace some leaking valves at both the launching and receiving ends of the pipeline.
Study on Viscosity Reduction Mechanism for Offshore Heavy Oil Under the Synergistic Action of Nanocatalyst and Ultrasound
Authors: Li Hanyong , Wang Yunlong , Qin Shouqiang , Cao Shuofang , Yu Bo , Sun Dongliang
Published: November 2020

Heavy oil resources are abundant all over the world, but its content of resin and asphaltene is high. Heavy oil has high viscosity and poor fluidity at room temperature, which brings great difficulties to heavy oil recovery and pipeline transportation. At present, the commonly used technologies of heavy oil pipeline transportation are heating transportation, emulsification viscosity reduction transportation and heavy oil mixed with dilute transportation, which have the shortcomings of high energy consumption and poor stability. In this paper, the structure and properties of a blank oil sample from offshore heavy oil and the oil samples dealt with the optimal experimental parameters were characterized by using the methods of ultrasonic alone, nano catalyst alone and synergistic action of nano catalyst and ultrasonic respectively. By means of four-component separation, elemental analysis and full two-dimensional gas chromatography and infrared spectroscopy analysis of light components, the changes of the contents of resins, asphaltenes, trace elements and light components as well as the types of functional groups in oil samples were measured. The results showed that the content of macromolecule such as resin and asphaltene in heavy oil was almost unchanged under the action of ultrasonic alone and the synergistic action of nano catalyst and ultrasonic. The content of saturated hydrocarbon in small molecule decreased to a certain extent, while the content of aromatic component decreased by 5.27% and 6.22% respectively. The peak values of infrared spectra changed slightly under three treatment modes. Among them, the peak values on the left side of the oil sample under the synergistic action of nano catalyst and ultrasonic decreased by 0.24 cm−1, and the peak values on the middle peak changed the most and increased by 0.95 cm−1 under the action of ultrasonic alone. Elemental analysis showed that the sulfur content of oil samples disappeared under the synergistic action of nano catalyst and ultrasonic and the action of ultrasonic alone, and the H/C increased most under the synergistic action of nano catalyst and ultrasonic, from 0.1310 to 0.1457. Two-dimensional gas chromatography showed that aromatic hydrocarbon content decreased, while alkanes (including C7-C40) and holosterols content increased under the synergistic action of nano catalyst and ultrasonic. It could be concluded that the viscosity reduction effect of heavy oil was the best under the synergistic action of nano catalyst and ultrasonic, and the viscosity reduction rate could reach 49.64%.

The above experimental results revealed to some extent the mechanism of viscosity reduction of heavy oil under the synergistic action of nano catalyst and ultrasonic, and provided reliable data reference and theoretical basis for submarine heavy oil pipeline transportation technology.
Delivering Best-in-Class Shallow Water Wellhead Platform, and Beyond
Authors: Loh Khian Aik , Chow Wan Han , Ngiam Shih Ming
Published: November 2020

While industrial revolution 4.0 transforming the manufacturing industry with the adoption of computers and enhanced with smart and autonomous system that comes with big data and machine learning capability, operators in oil and gas industry also embarked on its evolution, advancing in end-to-end project delivery efficiency through simplification and transformation, with the objective to deliver best-in-class project in a consistent manner.

This paper demonstrates a few key changes implemented by Civil, Structural and Offshore Engineering discipline to support the project delivery evolution by referring to a recent wellhead platform project Shell delivered. The principles of simplification and transformation were embraced since the early front end development phase, started from competitive scoping through the development of an intent/requirements-based technical requirements tailored to the project, considered all the key and relevant lessons learnt from respective operator combined with widely referred industry specifications. An intend-based design driven by efficient execution strategy has also shorten the fabrication and installation duration where early Mechanical Completion can be achieved by carefully bringing forward certain scope to front-end loading (FEL) with contractor's commitment to work within a stretched, proper-defined boundaries.

Another key change project implemented is through the enhancement in supply chain model that aims to accelerate the delivery schedule. Contractors were empowered and took full accountability under the EPC contract, after alignment of project intent, goals and owner/contractor interest. Cross-organization collaboration between operating units also allow project and/or sub-systems across projects to approach market in a joint campaign, benefits all parties from economy of scale.

The ultimate purpose of having efficient project delivery is to drive CAPEX down, enable more marginal fields development become economically feasible. Through the standardization of design requirements and smart replication, this will become the new baseline (in term of cost and schedule) to deliver future standard wellhead platform and transforming wellhead platform delivery to something like block manufacturing industry.
Extreme Ocean Current Profiles Classification in South China Sea
Authors: Loh Weitian , David Daniel , Anokhin Vadim
Published: November 2020

The objective of this paper is to derive representative vertical extreme current profiles for a location offshore Borneo continental shelf using statistical methods. Firstly, 95th percentile was used on one-year through the water column current measurements in 140 m of water to identify extreme current profiles. Principal Component Analysis (PCA) was then applied to the extremes to retain fundamental modes of the current dataset. The statistical approach was followed by K-means clustering analysis to objectively group the extreme current profiles. Lastly, actual weather and sea state conditions are examined to validate and explain each extreme current profile. Extreme currents are typically observed during the Northeast monsoon in South China Sea (boreal winter). From the statistical analysis, there are two prominent ocean current profiles observed at the location, (1) sheared profile with strong surface currents and (2) mid-depth current maxima. Type 1 profile is typically observed during strong winds, which lead to the formation of a wind-driven sheared profile with maxima at the surface. In contrast, Type 2 current profile has relatively weak near sea surface currents, while strong currents are observed at 60-100 m water depth. This profile is accompanied by a formation of mixing layer within a thermocline region and might be associated with the formation of basin-wide Kelvin wave in response to north-easterly monsoon.
Innovative Asset Integrity Management to Drive Operational Effectiveness
Authors: Constantinis Danny , Davies Peter
Published: November 2020

The floating Gas industry is growing rapidly. As with all sectors in boom times, the focus is firmly on output. We need to ensure safety, compliance and profitability of what are high value, complex assets some of which operate close to high population densities.

The speed of growth must be matched by an equivalent effort to maintain asset integrity while continuing production. Put simply, existing inspection and maintenance methods are not fit for purpose.

This paper describes a joint industry approach for addressing these challenges that has proved successful for FPSOs.

The industry needs to operate with high levels of asset integrity, with a programme of continuous improvement and with a long-term planning view. Effective Asset Integrity programmes are a key part of the strategy, and it is widely agreed that better use of data and robotics will help reduce unnecessary work and human risk.

The HITS (Hull Inspection Techniques and Strategy) JIP, part of the FPSO Forum, has a membership made up of oil majors, service providers, classification societies and regulators. It has encouraged the development of new technologies, which have significantly improved safety and reduced operational costs.

Drawing on experiences of other industries, the HITS JIP has driven innovation; safer, more cost-effective, more efficient technology, which has led to less impact on core operations of floating production assets: these include:

The gas industry provided a means of placing nuclear industry miniature cameras into sea chests and isolation valves so that they can be inspected without affecting operations; Hull inspections were improved using deck launched, remotely operated underwater vehicles (ROVs) adapted to carry out cavitation cleaning of sea chest inlet grids, impressed current cathodic protection (ICCP) anodes and points of structural interest, such as bilge keel end connections; The forestry industry provided the idea for chain crawlers for inspection and repair of deep-water moorings; From the Nuclear industry, robotic inspections using high performance cameras, adapted to be inserted through Butterworth hatches or purpose-fitted ports in the deck enabling general and close visual inspection to meet regulatory requirement without the need for confined space entry; To protect the hull, diverless ICCP systems, deploying retractable anodes through the hull; and For pressure systems, using data more effectively; inputting inspection data to confirm fitness for service to an agreed level of confidence.

This paper describes a joint industry approach for addressing these challenges that has proved successful for FPSOs.

It will describe the steps that have already been taken to create an industry wide group including operators, class, regulators and service providers, to agree the primary challenges and to encourage development of solutions in a cost-efficient way.

It will describe how innovations developed and proven in the FPSO and other sectors can be successfully introduced to this sector.
Innovative Analysis Approach for Installation of Flow–Line End Termination Structure in Rough Weather
Authors: Shahyarfar Shahreyar , Sinha Ritesh Kumar
Published: November 2020

The installation of subsea structures in deep water comes with a variety of associated challenges. These installation operations usually weathered sensitive. One of the important factors for project success is to have an allowable weather window (to carry out the operation safely) as wide as possible. TechnipFMC installed two rigid pipelines and four FLETs (Flowline end termination structure) for a project offshore North West of Australia. Installation of the pipeline and structures were carried out by DP2 pipelay vessel "Global 1201". The weather in North West Australian waters is known for high swells with long period and cyclones throughout the year. It leaves a limited time window for operations and demands a robust and efficient installation methodology.

This paper presents the innovative installation techniques and analysis approach adopted to overcome the challenges faced for the installation of the FLETs (Flowline end termination structure) in rough weather conditions.
Floating LNG 1 Relocation: Another World's First
Authors: Jais Muhammad Fakhruddin , Wan Hashim Wan Mahsuri , Ayadali Ariff Azhari , Idrus Aishah
Published: November 2020

Floating Liquefied Natural Gas (FLNG) allows for the processing of LNG to be done offshore, hundreds of kilometers away from land. Its versatility enables the unlock the gas reserves in remote and stranded fields that were previously uneconomical to explore, making it possible to monetize those fields far out at sea. In order to fast track the project, an evaluation of the new feed gas composition and modification of both upstream and FLNG facilities was conducted. The identified Long Lead Items (LLI) initiated and studies being conducted in-house to secure the items. An integrated upstream facilities and FLNG team had been established for the execution of the project. In March 2019, the floating LNG unit embarks to fulfill its technological life cycle and was relocated to monetize another stranded field some 450km away from its original location. The overall journey of the relocation took 13 months to complete, right from the inception of the idea to the first drop of LNG in Sabah waters. This paper serves to share Petronas experience in overcoming the challenges of the facility's relocation, starting from selecting the new field until the loading of LNG at the new location.
Directional Casing While Drilling : Challenges and Constraints in Drilling into Carbonate Reservoir through a Dual Splitter Wellhead System
Authors: Majid Allapitchai M Shahril , Wong Han Sze
Published: November 2020

Casing while drilling is seen as a cutting edge technology which enables operators to save time and successfully deliver a well's objective. The reliability of the system often results in the technology to be deployed in challenging environments. In this campaign, operator encountered an unforeseen layer of carbonate (thief zone) during the first well of the campaign which resulted in a change of direction in the well planning and engineering of subsequent 2 wells which were drilled through a dual splitter wellhead system. This paper will discuss on the strategies, challenges and operational steps taken to successfully drill through and cased off the said carbonate formation, by using Directional Casing while Drilling (DCwD) in dual splitter wellhead system.

Casing while drilling has shown high reliability in combating top hole section drilling with fluid losses and hole stability issues. However, there are only a handful of cases worldwide where DCwD has been deployed in managing severe losses conditions such as total loss. The presented case took place in a matured development field where severe losses occurred after unexpectedly penetrating a carbonate formation in top hole section which was not experienced in any of the nearby offset wells. To mitigate the wellbore issues, DCwD was utilized for the subsequent wells.

Several different approaches were taken in completing both wells in a dual splitter wellhead system. The engineering design, drilling practices, cementing strategies and best practices which were refined over time based on lessons learnt during the campaign will be shared in this paper. This information is coupled with analysis and reasoning behind each procedure that were used to complete these wells.

Both wells were successfully drilled and cased off, with less time spent to combat formation related challenges compared to conventional drilling. Intended top of cement in the annulus was achieved by improving the cementing strategy which minimizes time and cost to seal the thief zone. A few new challenges emerged during the execution and these challenges are discussed and addressed in this paper.

Even though there are numerous challenges in completing both wells, it can be concluded that DCwD is a viable technology in helping to mitigate wellbore issues (total loss carbonate section). The change of strategies to deploy DCwD has proven to be viable with 2 wells successfully drilled and cased off under splitter wellhead system. The concept, challenges and best practices presented in this paper will help to provide valuable reference as well as a guideline for future similar operations.
Understanding Compartmentalization of Deepwater Reservoirs
Authors: Shoup Robert Charles , Jong John , Barker Steven M. , Khamis Mohd Asraf
Published: November 2020

Objective/Scope

The high cost of deepwater developments and the limited reach from offshore platforms requires operators to have a good understanding of the expected reservoir compartmentalization in the field before the first well is drilled. Deepwater reservoirs can be compartmentalized both structurally and stratigraphically. This paper will briefly address the structural compartmentalization and discuss the stratigraphic baffling that occurs in deepwater depositional settings.

Methods, Procedures, Process

The distribution of reservoir facies within deepwater depositional settings is well-understood from outcrop studies, seismic facies mapping, and exploration and development drilling. This understanding can be used to predict where stratigraphic compartmentalization is likely to occur.

Results Observations and Conclusions

Channel levee complexes and crevasse splays are deposited principally on the slope. Deposits are typically characteristic of a meandering river. Fluid flow in channel levee complexes occurs principally along the channel thalweg. Small-scale slumps within the channel levee complex may baffle flow from the levee into the channel thalweg. Crevasse splays are deposited when there has been a breach in the levee. The reservoir distribution in a crevasse splay deposit is characteristic of a river-dominated delta. Fluid flow in a crevasse splay will be generally toward the channel breach.

Submarine fans are deposited in structurally restricted basins on the slope or on the basin floor. Interbedded shales baffle vertical fluid flow, with lower or distal lobe deposits more vertically baffled than upper lobe deposits. Lateral baffling of fluid flow in lower fan deposits is generally caused by small faults. In the middle to upper fan lateral erosional channels as well as small faults can baffle lateral fluid flow.

Gorges or canyons are incisional events. They can occur anywhere on the system but are more common and more deeply incised in the upper fan and slope. The reservoir facies that fill the gorge are typically sand-prone, with sand more prevalent in the lower gorge-fill.

Debris flows and slumps can occur anywhere in the system. Since reservoir connectivity within the debris flow is minimal, these should not be targeted for development.
Application of the Micro Biological Survey analytical method for the determination of bacterial load in cow raw milk
Authors: Cornacchia Alessandra , Saletti Maria Antonietta , Di Marzio Violeta , Salini Romolo , Marfoglia Cristina , Tieri Elga , D’Alterio Nicola , Marri Nicla , Losito Francesca , Arienzo Alyexandra , Murgia Lorenza , Antonini Giovanni , Amatiste Simonetta , Leboffe Loris , Pomilio Francesco
Published: November 2020

The aim of this study was to evaluate the performance of “Micro Biological Survey – MBS Test” in the enumeration of bacterial load in cow raw milk. The MBS test is based on a colorimetric method recently developed and patented by “Roma Tre” University, Italy. The evaluation of the performance of the MBS method was carried out by comparison with plate count at 30°C (gold standard) and flow cytometry. Thirteen independent set of experiments were performed analyzing a total of 104 samples of cow raw milk with the selected methods. Results obtained using the MBS method are comparable with those obtained with the plate count method at 30°C (CFU/mL) and flow cytometry technology; in particular, the results obtained with the MBS method are very close to plate count’s at 30°C. On the other hand, there are statistically significant differences between these two methods’ and flow cytometry technology’s results that could be due to the different experimental conditions.
Trauma, violence and recovery in the life stories of people who have injected drugs
Authors: Hammersley Richard , Reid Marie , Dalgarno Phil , Wallace Jason , Liddell Dave
Published: November 2020

This paper reports qualitative data about violence and trauma amongst drug injectors in Scotland, collected using a life story method with 55 drug injectors currently in recovery. It focusses on different types of violence and trauma that occurred whilst using drugs. Stories told of very severe and repeated traumas often involving extreme violence. One motive for escalating and continuing drug use was avoidant coping to deaden the emotions and thoughts regarding these traumas. Many traumas were due partly to the criminal drug milieu, so respondents were in a vicious cycle of using opiates and other sedative drugs to cope with the consequences of being involved in a lifestyle of using, supplying and obtaining illegal sedative drugs. Drugs were used as a dynamic method of self-medication or avoidant coping to cope with life in a criminal milieu. Traumatic events were more often described as worsening the lifestyle than as being motives for quitting. Amongst the traumas recounted were many incidents of extreme violence. Using drugs to block the psychological effects of such traumas may help explain why people persist using opiates despite experiencing evident serious harms. Interventions need to recognise this, be trauma-aware and appreciate that violence and trauma have severe adverse effects on drug injectors even when they are themselves hardened and violent.
Central giant cell granuloma in a child
Authors: Kumari Nisha , Sarangal Heena , Beniwal Disha , Namdev Ritu
Published: November 2020

An intraosseous lesion of jaws called central giant cell granuloma (CGCG), is significantly found in children and young adults and most of the cases are nonaggressive, asymptomatic, and slow growing. Approximately 30% of cases show an aggressive and progressively devastating nature with tendency to recur. We present a case of slow growing CGCG in mandible in a 10-year-old male managed by curettage along with preservation of tooth germ.
Conservative treatments for acute nonarteritic central retinal artery occlusion
Authors: Sharma Rahul A. , Newman Nancy J. , Biousse Valérie
Published: November 2020

Acute central retinal arterial occlusion has a very poor visual prognosis. Unfortunately, there is a dearth of evidence to support the use of any of the so-called “conservative” treatment options for CRAO, and the use of thrombolytics remains controversial. In this review, we address a variety of these “conservative” pharmacologic treatments (pentoxifylline, isosorbide dinitrate, and acetazolamide) and nonpharmacologic approaches (carbogen, hyperbaric oxygen, ocular massage, anterior chamber paracentesis, laser embolectomy, and hemodilution) that have been proposed as potential treatments of this condition. We conclude that the available evidence for all treatments is insufficient to conclude that any treatment will influence the natural history of this disorder. Management of CRAO patients should instead focus on reducing the risk of subsequent ischemic events, including cerebral stroke. Certain patients may be considered for acute treatment with thrombolytics, although further research must clarify the efficacy, safety, and optimal use of these therapies.