bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrity Assurance of Critical Common Pipelines of Two ADNOC OPCO's. A Success Story
Authors: Sabry Houssam
Published: November 2016

Das Island facilities are operated by two OPCO's namely ADGAS and ADMA OPCO. ADGAS receives it sgas for processing through its sister company ADMA-OPCO. ADGAS and AMA-OPCO have joined forces to ensure the integrity of the common piping. Common piping is of high criticality. High criticality is driven by the high consequence of failure of these common lines. A task force was created to review the battery limit definition hence allocate the accountability of each section, this is in addition to risk assess all common lines.

Task force started its works on the 6th of April 2015 and concluded its works in December 2015.

Task force established a common piping asset register, this was followed by desk top demarcation followed by physical demarcation. Afterwards, risk assessment was done jointly on all common facilities. Inspection strategies was greed between the two teams. Results and findings of integrity management would be conducted on quarterly bases.

We hereby thank both sister company's management for their support towards the success of this exercise which we see as a role model of cooperation between the two sister companies.
Innovative Cutter Layout Technology Minimized PDC Bit Vibrations with RSS Tool and Helped in Placing Borehole Accurately While Drilling in Tight Reservoirs
Authors: El-Gayar Mahmoud , Horra Hichem , Maouche Zakaria
Published: November 2016

Exploration and production of horizontal unconventional tight reservoirs is a growing market in the Middle East. Drilling challenges require precise horizontal steering control relative to the severe formation tendency to achieve higher degrees of accuracy in borehole placement while improving the overall rate of penetration (ROP). This paper discusses the interaction between the polycrystalline diamond compact (PDC) bit cutting structure and rotary steerable systems (RSSs) with respect to vibration alleviation.

Steering using a RSS requires a special bit design to enhance the dogleg capability and ensure minimum vibration levels. A new PDC bit was designed using innovative multilevel force balancing technology—a new theory on PDC cutters layout in force-balanced groups. A group of three or four single-set cutters on a bit profile form a force-balanced cutter group; by carefully selecting the order of layout cutter groups, a new feature of the PDC bit is obtained, ensuring the efficient removal of any ring of rock in a balanced environment.

The new PDC bit design and the implementation of the integrated engineering softwares used to analyze offset wells vibration data, drilling parameters, bit walk tendency, and rock mechanics had a significant effect on the run performance. The clear reduction in the vibration levels enabled more parameters to be applied; thus, helping overcome the formation tendency of the tight reservoir and finishing the run with a good ROP. The even distribution of the cutting forces as a result of the multilevel force balancing of the bit cutting structure reduced the imbalance forces induced as the bit entered transit formation. This increased the overall bit stability, reduced vibration levels, and increased drilling efficiency.
Jet Mill Bit for Improving Cuttings Carrying Capacity in Horizontal Gas Drilling
Authors: Chen Xuyue , Gao Deli
Published: November 2016

Cuttings accumulation is a major challenge in horizontal gas drilling, it may lead to accidents such as wellbore plugging and pipe sticking. The newly-developed jet mill bit (JMB) may overcome the challenge fundamentally by comminuting cuttings into dusk-like scale right after the cuttings are generated. In this paper, the JMB is investigated as an innovative method to improve cuttings carrying capacity in horizontal gas drilling. It presents the JMB's working principle and cuttings-comminuting mechanism, and explains why it is developed based on the analysis of cuttings carrying capacity in horizontal gas drilling. Analysis using field data in the published article demonstrates that the max cuttings that can be carried by the annular gas are dust-like and much smaller than the initial cuttings size in the high angle build section and horizontal sections, it needs several times as much gas injection volume as the current annular gas injection volume to eliminate cuttings accumulation. JMB can comminute cuttings in dusk-like scale and may eliminate cuttings accumulation fundamentally, meanwhile drilling complications such as near bit hole washout, hole deviation, and ice-balling (frozen) of bit can also be avoided in horizontal gas drilling.
Adapting Field Development Plan of Compartmentalized Oil Rim Reservoir with Significant Gas Cap and Water Aquifer - Case Study
Authors: Gazar Ashraf Lotfy , Shabibi Tariq Ali , Loredo Lenin , Kumar Ravi , Syofyan Syofvas , Al-Naqbi Sheikha , Alklih Yousef
Published: November 2016

The paper is continuation of SPE-177659, This work illustrates adapted field development plan and optimization studies conducted on a Middle-Eastern compartmenlized complex carbonate oil rim reservoir with significant gas cap and water aquifer. The need to expedite the field development was realized based on increasing gas demand for the country as well as fast pace of urbanization in area which can potentially complicate the field development in future with regard to availability and accessibility of drilling sites. The surrounding fields have seen ranges of H2S concentartion in compositionhence, public safety is a major concern. PVT studies indicate a wide range of compositions which further complicates the development plan considering the surrounding sensitive environment. The reservoir exhibits relatively fair to poor reservoir characteristics, variable contacts and composition variation across the reservoir due to faulting- suggesting the presence of multiple reservoir compartments. To exploit the sweet spots of a thin oil rim in highly faulted reservoir is a major challenge considering limitation on drilling location and horizontal reach. The scenarios of field development and economics were created for developing the reservoir as oil as well as gas development.

A total of 10 wells had penetrated the reservoir out of which 8 wells tested oil and suggested a significant initial gas cap while 2 others penetrated water leg. Six years of early production scheme (EPS, 4 producers, 1993 to 1998) data in addition to production testing, core (2 wells), MDT (3 wells), PVT (4 wells) data were gathered in order to identify the main uncertainties and test the feasibility of the full field development. EPS indicated production decline coupled with severe increase in GOR and water cut in some wells, after which the producing wells and facilities were P&A due to safety concerns and low productivity.

A number of parameters were addressed and optimized as a part of full field development plan. The dynamic modeling suggests that an ultimate recovery of 70% can be achieved by the different injection scenarios. However, considering the complexity of the surrounding environment and the size of the prize, it is recommended that the field development should be consideredfor a period of 10 years under natural depletion considering economically viability, provided the most effective development strategy in terms of number, location, orientation and horizontal reach is adopted.

Initially it was planned to develop the field as oil rim development however the development strategy was adopted to develop the gas cap instead of the oil rim considering urgency of development, low oil price forecast in short term, better economics and the country gas demand. This work discusses the influence of different parameters including the human landscape on decision making.
Overcoming Hazards in Sour Gas Sampling by Controlled Measures
Authors: Haji Abdirehman , Veerakumar Ukkirapandian
Published: November 2016

Objective

Sampling and analysis of sour gas is hazardous and can lead to fatality if appropriate safety precautions are not taken. Similarly if improper technique or instrument is used for measurement, it might lead to high error and the results will be unreliable for process control. The prime objective of this paper is to develop safe sampling and lab analysis procedure and adapt right analytical technique and instruments for accurate measurement of chemical composition of sour natural gas.

Method, process

Sour gas contains hydrocarbons ranging from C1 up to C9+, carbon dioxide, oxygen, hydrogen sulfide etc. and its composition depends on the source, operating conditions etc. A novel technique of sample collection with strict safety regulations and adequate protective equipment's are implemented to avoid exposure to toxic H2S gas. Right configuration of sampling point connected to flare system with control valves and tools help us to extract a representative sample without any leak into atmosphere. An extended training in handling such toxic gas is provided to the staff performing sample collection and analysis. The conventional method for analysis of sour gas composition is GPA 2261 using gas chromatograph which is inadequate and the gas composition is incorrect due to fractionation or condensation of heavier fractions.

Results, discussion and conclusions

We have changed the configuration of the gas chromatograph adapted a modern technique of sample stabilization using a temperature controlled oven and enable automatic injection of several samples through programmed sequential operation. The results show good repeatability and high sensitivity for heavier fractions and other components. The equipment is calibrated before testing the sample with a primary standard of known composition. The results of both detectors (TCD for inert and permanent gases and FID for hydrocarbons) are combined using i-pentane and n-pentane as bridge compounds and calculated the relative response factors for each component and the gas composition. Applying the novel techniques of designing proper sample points, using right tools and modern instrumentation, we could ensure that the sample is homogenous and representative of the bulk supply in plant. We could completely eliminate exposure to toxic H2S gas by using personnel protective equipments and avoid any leak in to atmosphere by connecting it to flare. Changes in the configuration of gas chromatograph, test conditions and parameters helped us to improve the accuracy and precision of measurement. These simple methods of sampling and analysis of sour feed gases is applicable to all oil and gas industries and sharing these safety guidelines and right approach for accurate analysis will help the operations team. This is an effort towards our commitment to safety of personnel and operational excellence.
Identifying the Cause of Unexpected Solids Deposition from a Sodium Bromide Completion Brine in a Giant Field, Offshore Abu Dhabi
Authors: Aouda Abdel Hakim , Monem Alaa Abdel , Daghar Tariq Al , Stalker Robert
Published: November 2016

To achieve the new increased production rate of a giant oilfield offshore Abu Dhabi, the operator started implementing a number of new technologies which push back the boundaries of technical expertise. Foremost among these is the construction of four artificial islands from which wells are being drilled using extended reach drilling (ERD) technology and the use of maximum reservoir contact (MRC) wells to maximise potential production.

To ensure that the maximum benefit was obtained from these MRC wells, an extensive research and testing program was conducted to select an optimised completion fluid for use in the island wells to improve and maximise production. The resulting selected sodium bromide/sodium chloride (NaBr/NaCl) based completion fluid was used in the pilot MRC wells and is now being used successfully in new wells on the islands with significant improvement in production. However, shortly after the start of production from one well, an unexpected production upset occurred with the appearance of significant quantities of solids at the surface non-return valve (NRV). Laboratory analysis of these solids confirmed that they consisted primarily of mineral scales, with sodium bromide (NaBr) and sodium chloride (NaCl) predominant.

To avoid major disruptions in the production system, the following key questions during the investigation required urgent answers: Why were these salts depositing in this production system?Why were similar issues not reported in other wells using the same completion brine?Were there any specific differences in this well or its operation that could cause the solids being formed?Are any mitigation measures required for the continued use of the NaBr/NaCl completion brine in the island wells?

This paper describes the detective work undertaken to investigate the unexpected appearance of these solids in the production system. This involved a combination of field data review, mineral scale prediction modelling and laboratory tests and analysis. The cause of the solids deposition was identified as being due to the interaction of the completion brine with the hydrocarbon phase at very low water cuts. It should be noted that other wells are also being produced at low water cuts without any similar issues occuring. By investigating and understanding this problem more fully, a set of guidelines and improved testing protocol could be developed to use in any repeat investigation. At the time of writing this paper no further problems have occurred in any of the subsequent wells drilled and produced.
Novel Approach to Restore Integrity to Downhole Safety Valves from Damaged Landing
Authors: AL-Mutairi Ali , Sayed Mohamed El , Ali Mohamed Saleh , Bhatti Ali
Published: November 2016

Well Integrity management standards require wells to be equipped with two independent barriers to protect against uncontrolled flow of hydrocarbons from the reservoir to the environment. For producing wells the two barriers are usually the downhole safety valve and the surface X-mas tree. I-DHSVC is integral solution, implemented 1st time in region, for wells suffering from damaged DHSV landing nipple profile. Damage could be related to lock profile, seal bore profile or both. It's a perfect solution for the wells with damaged DHSV landing nipple but with integral control line.

Sometimes, DHSV cannot be stay in the landing nipple due to damaged lock profile, causing it to pop up during the production. This situation leads to high risk scenario (risk rank-1). IDHSVC does not use damaged nipple profile for anchoring as its slips anchor in the flow coupling above & below the landing nipple. A standard DHSV is connected to bottom of IDHSVC, which sets by either Slick line or by E-wireline utilizing nitrogen charged hydraulic setting tool. DHSV can be operated normally using existing control line. IDHSVC can be retrieved utilizing slick line with GS pulling tool without any Barge/Rig.

The benefits from the project are sustained "year-on-year" with the restoration of full integrity to the wells which enables ADMA-OPCO to meet its production targets in a cost effective manner.
HSE Governance Concerns and Challenges in a Potential Oil and Gas Producer
Authors: Ibrahim Assem Abou , Sheikh Rola , Rachid Grace
Published: November 2016

With the latest discovery of oil and gas fields in the Eastern Mediterranean region, the concern about safety accidents and oil spills in this fragile social and natural ecosystem is continuously increasing. This paper discusses the approach of the Lebanese Petroleum Administration (LPA), as the upstream oil and gas regulator in Lebanon, towards proper health, safety and environment (HSE) management of the upcoming oil and gas sector. The potential challenges to the sector are excacerbated with existing inconsistencies in regulations, conflicting mandates, weak enforceability, lack of resources and political conflicts. A review of the existing HSE legal and regulatory framework was undertaken to identify gaps and challenges in addition to the mapping of relevant stakeholders. In parallel, a benchmarking of international HSE goverance and management systems in the oil and gas sector was necessary to gauge latest approaches and best practices in the industry to guide the development of a HSE framework in Lebnaon. The analysis covered the characteristics and implications of each of the prescriptive, risk-based and hybrid approaches to HSE management. It highlighted the importance of a very clear distinction between the authority that issues the operating licenses and the authorities that regulate safety and environment in order to prevent conflict of interest and install a natural checks-and-balance system. The study proposes a risk based hybrid HSE governance framework for implementation in Lebanon, as well as, develop a roundmap for the development of this HSE regulatory framework. In parallel, and based on lessons learnt from the Jiyeh 2006 oil spill, the largest oil spill in the Eastern Mediterranenan, an update of the national oil spill contingency plan is undertaken in light of IMO and IPIECA guidelines. This study reconfirms how benchmarks, case studies and context analysis can effectively inform governance in emerging structures facilitating necessary mindset shifts and mainstreaming the needed HSE culture.
Uncertainty Quantification in the EUR of Eagle Ford Shale Wells Using Probabilistic Decline-Curve Analysis with a Novel Model
Authors: Zhukovsky Isaac D. , Mendoza Ruben C. , King Michael J. , Lee W. John
Published: November 2016

This paper proposes a Bayesian decline curve methodology, using Markov Chain Monte Carlo (MCMC) simulation and a novel empirical decline curve equation (Zhang et al., 2015) to better quantify uncertainty in estimated ultimate recovery (EUR) for oil shales. The methodology was calibrated using hindcasting of production data from an area of the Eagle Ford oil window. Hindcasting, on an areal basis with 254 wells has demonstrated good results, with a coverage rate of true reserves of 78% for an 80% confidence interval (P90-P10) or 199 of the 254 wells tested. The novelty of the new model is in the implementation of the empirical decline curve equation for shale wells in Bayesian decline curve analysis with fast per well solution time on typical engineering computers

This method offers many benefits. Principally, the method quantitatively assesses uncertainty and avoids subjective estimates of uncertainty. The results the method generates are accurate for shale wells because the decline curve equation was empirically designed for such wells. Furthermore, it generates replicable results for given wells regardless of the forecasting engineer and offers a fast calculation time of 5-10 seconds per well in the data set.

The novel decline curve equation used in this methodology accommodates both early steep rate decline and later shallower decline with a smooth transition. Coupled with a Bayesian decline curve analysis process, the decline behavior of shale wells was assessed probabilistically with accuracy. The decline curve parameters are random variables with defined prior distributions. A MCMC simulation was performed to obtain the posterior distribution of well EUR's. Wells in the sample set had >36 months of production with the first 12 months used as simulation input. The method was calibrated (hindcasted) on an areal basis by measuring the coverage rate of "true reserves." The method, when applied to the Eagle Ford oil shale production data, demonstrated good convergence to stationary posterior distributions of the parameters. This is important because field development of the Eagle Ford and other shale plays is improved when uncertainty is accurately quantified. By quantifying uncertainty and moving away from deterministic decline curve analysis using equations designed for conventional reservoirs, a better understanding of shale well EUR and behavior throughout a play is obtained.
Integration and Data Analysis of Conventional Core Data with NMR and CT Data to Characterize An Evaporitic Carbonate Reservoir.
Authors: Fitzsimons Daniel , Oeltzschner Gunnar , Ovens Christopher , Radies Dirk , Schulze Frauke
Published: November 2016

Acquisition of whole core data allows detailed rock typing profiles to be defined which are required to assign flow properties for dynamic reservoir simulation. Conventional core analysis provides lab measurements of porosity, permeability and pore size distribution sampled at plug locations with a limited sampling increment. Whole core CT scanning allows for a more continuous detailed evaluation of the cored intervals which allow the precise boundaries of specific Rock Types to be defined. This paper illustrates how novel techniques of data analysis and graphic displays of both whole core CT data and wireline NMR have been used to aid the definition of Rock Types and Flow Units.

Rock Types have been categorized based on flow properties using plug porosity, permeability and MICP data. Processing of whole core CT data and wireline NMR has been performed in order to assess the heterogeneity measured by both acquisition methods. For the CT data set Heterogeneity Logs have been generated, these logs display the variation of CT density of the whole core. The logs have enabled very fine scale definition of lithotypes. In a similar manner the NMR logs were also analyzed and processed to extract specific statistical moments such as modes, magnitudes and skewness. Both sets of data were then integrated with core analysis data and thin sections. Excellent correlation between core plug, CT Heterogeneity Logs, NMR and thin section pore size distribution was observed and this has enabled the definition of Rock Types from the fine scale CT Heterogeneity Logs and Flow Units from the coarser scale wireline NMR data.

The techniques described are applied to data from a heterogeneous evaporitic carbonate reservoir, where pore size distribution has a major effect on permeability and productivity. Eight Rock Types have been categorized from core analysis and these have been propagated from plug locations using the CT Heterogeneity Logs to assist manual interpretation. Neural Network and geostatistics were applied to propagate to uncored wells and throughout the geocellular model.

The acquisition of core data and subsequent Heterogeneity Logs from whole core CT has proved very beneficial in the understanding of the wireline NMR tool response and has given confidence in the predictive ability of NMR to distinguish reservoir Flow Units in uncored intervals or wells.
First Successful Cuttings Reinjection CRI Operation in Ecuador: An Alternative to Help Minimize the Environmental Impact in a Protected Area
Authors: Romero Luis , Ramirez Orlando , Hernandez Rubys , Bastidas Alejandro
Published: November 2016

This paper discusses a technology for waste management and disposal through cuttings reinjection (CRI). The fully integrated process was successfully applied in the Ecuador Apaika-Nenke field, which is an area with significant oil potential located in the heart of a protected biodiverse zone. The advantage of the applied process, from candidate selection screening to the detailed implementation phase, represents a permanent drilling solution in environmentally sensitive areas.

This paper presents a case study of CRI in an Apaika injection well. The well was chosen based on feasibility tests and previous injectivity test results, making it the first drilled waste reinjector well in Ecuador supported by best practices. This paper describes injection equipment used for the slurry process and injection into the formation, waste collection and transportation from the rig site to the CRI facilities, slurrification process describing how the cuttings are treated for reinjection, injection parameters given by the feasibility study, and pressure response to injection explaining how the formation will react in time to the slurry injection. Each slurry injection was performed in 12-hour cycles instead of continuous injection, allowing the formation to reach pseudoequilibrium stages while the cuttings migrated within the selected structure through fracturing conduits.

From June 2014 through December 2015, 209,000 bbl of slurry from 11 drilled wells were injected into the disposal well. All the waste fluids (dewatering water, cutting pits rainwater, and rig wash) were used for the preparation of injection slurry, reducing chemical use for the dewatering process. The well was also used for disposal of produced water with more than 400,000 bbl injected. The cyclic injections were conducted in three stages: preflush, post-flush, and slurry injection pumping to displace the entire tubing volume and minimize well plugging risks. During the first stage, wellhead pressure and slurry properties were monitored to help establish accurate injection parameters. No significant changes were observed in terms of pressure performance at a maximum pressure differential of 2,000 psi during the three stages. The first CRI met all expectations of not leaving any cutting on surface. All the cuttings and drilling waste from the Apaika-Nenke pads were reinjected without any operational inconvenience. For future wells, deforestation will not be necessary for new cutting pits in this sensitive area, helping minimize the environmental impact and addressing social challenges and inherent risk present within the oil industry.

The application of CRI in the Apaika-Nenke field demonstrated that drilling in a sensitive area could be performed with high environmental standards and in compliance with local environmental laws with excellent results.
Timelapse Borehole CSEM for HC-Saturation Monitoring in the Bockstedt Oilfield Onshore NW Germany
Authors: Tietze K. , Ritter O. , Patzer C. , Veeken P. , Verboom B.
Published: November 2016

Production from oil fields requires monitoring of hydrocarbon saturation in the reservoir. In the Bockstedt oilfield there exists a substantial difference in resistivity between oil-filled (approx. 100-16 Ohmm) and brine-filled (0.6 Ohmm) reservoir. Electromagnetic method is chosen to test whether sufficient resistivity differences can be observed via surface measurements. The target is a Lower Cretaceous clastic interval located at an approximate depth of 1200 metres.

Forward modelling demonstrates that the expected resistivity changes at reservoir level cannot be resolved with a survey setup of only surface electrical sources and sensors. Therefore a borehole-to-surface technique has been developed, whereby the metal casing of an abandoned production well serves as input electrode. CSEM surveys were acquired in 2014 and 2015 as timelapse baseline and monitor for both Ex and Ey components. Forward modelling indicates that induction effects from metal objects like casings of production wells cannot be ignored in the EM modelling. A shallow observation well was drilled in 2015 to make collection of Ez datasets possible. A new downhole sensor was developed for this purpose. Numerical simulations suggests Ez data is more sensitive to the anticipated resistivity changes. Since Ez is two orders of magnitude smaller than the horizontal components, verticality is of great importance to avoid masking the Ez signal by interference from unwanted horizontal components.

Similar acquisition parameters are adopted for 2014 baseline and 2015 monitor surveys to facilitate the comparisons. The repeatability is good, generating comparable response functions. The earth model, retained so far by the inversion algorithm, confirms the main resistivity units seen by the resistivity logs in the calibration well. Incorporation of the metal casings in the EM modelling scheme increases the lateral continuity of inverted resisitivity bodies.

This study is a follow-up of work presented in the 2015 ADIPEC conference. In November 2016 a new acquisition campaign will be undertaken to collect a second Ex – Ey monitor and the first monitor survey for the Ez component. A limited time-lapse test has been performed in spring 2016 to monitor Ez with only 1 source station incorporating the borehole electrode Bo-23.
Practice and Lessons Learned for the Development of Naturally Fractured Carbonate Gas Reservoir in Weiyuan Gas Field of Sichuan Basin, China
Authors: Wan Yujin , Su Yunhe
Published: November 2016

Dengying gas reservoir in Weiyuan Gas Field is classified as a fractured dolomite gas reservoir with extreme low matrix permeability and bottom water. The ultimate gas recovery is only 37% in the wake of 50 years’ exploitation. By integrating core analysis, well logging interpretation and dynamic performance analysis, we investigate the key factors affecting gas recovery. Firstly, fractures are the main pathway both for gas to flow into the wellbore and water to invade into the gas reservoir. Secondly, the great amount of water produced from gas wells boosts liquid loading and therefore increases the additional pressure loss in the borehole dramatically. Thirdly, the trapped gas, isolated in the matrix from intermittent production after watered-out owing to non-uniform water flow through the fractures, could not be recovered. For this reason, some imperative measures should be taken to improve the gas recovery. On the one hand, a reasonable flow rate of the gas well should be optimized for preventing from water invasion and extending water-free production period. On the other hand, dewatering is a practical method to extend the life span of the producing well and to improve the gas recovery.
Innovative Geo-Steering Approach with Reservoir Bed Boundary Mapping Impacts Drilling Performance
Authors: Almusallam Ali A. , Yahya Hany A. , Hamid Ab , Halim Abdul , BinAli Ali N. , Ashraf Omar T. , Ghazzawi Ayman A. , Balka Muhammad S. , Samaroo Rajeev B. , Mohiuddin Mohammed A. , Alatiyyah Ahmed S.
Published: November 2016

Combination of well design practices, geo-steering with neutron-density and multilayer bed boundary mapping tools with a motorized rotary-steerable service (RSS) bottom-hole assembly (BHA) has been successfully used in the Ghawar field to accurately detect multiple formation layers enabling drilling performance improvement and optimized well placement services in challenging carbonate wells. The objective of the work-over program is to establish water-free gas production from the reservoir, especially as the gas-water contact (GWC) rises with on-going production. The Ghawar field is located in the eastern part of Saudi Arabia which contains non-associated gas in the target formation varying greatly in depth from the North and South of the field. The target formation consists of major gas bearing intervals, known as Carbonate Layer A and Carbonate Layer B. The Carbonate Layer-A averages about 120 ft in gross thickness and consists primarily of dolomite capped by anhydrite. The Carbonate Layer-B formation, like the Carbonate Layer-A, consists mainly of dolomites capped by tight anhydritic dolomites.

In addition, these wells are drilled in the minimum horizontal stress directional for the advantages of optimized hydraulic fractures during stimulation phase and thus improved productivity. But these wells are notorious for stuck pipe risks, tripping difficulties and slow drilling penetration rates (ROP) with high shocks and vibrations. These risks are primarily due to geo-mechanical wellbore instability and uncertainty in both GWC depth and reservoir pressures arising from the strategy of drilling through multiple layers. With very low contrast in resistivity and the complex nature of the targeted reservoir, steering with only resistivity contrast using conventional bed boundary techniques would not suffice. Ideally, steering in a single layer of the target formation will eliminate the risks associated with the traditional steering method of passing multiple layers.

Neutron-density combined with a new multilayer bed boundary mapping service were successfully deployed in deep gas Udhailiyah on four different wells. This service provided precise delineation of targeted reservoir layers in addition to giving an estimate of formation dip resulting in faster and more accurate geosteering. Steering effectively in these complex thinly bedded reservoir layers has shown improved drilling and tool reliability indicators, including incremental ROP improvement, zero stuck-pipe incidents, stick-slip and shock reduction, and the confidence to push with maximum parameters with a motorized RSS BHA to minimize open hole exposure and avoid borehole deterioration effects with time.
Successful Application of Wireless Bottomhole Data Transmission in the UAE—Bringing Certainty During Well Test Operations
Authors: Mustafa H. , Al Shateri A. A. , Kuliyev M. U. , Kutty S. M. , Chitre S. N. , Al-Marzooqi A. M. , Iabbassen N. , Cesetti M. , Baslaib A. , Hollaender F.
Published: November 2016

As part of ongoing efforts to develop greater gas and oil resources in the UAE, appraisal of several fields discovered decades ago accelerated in 2015 and 2016. Drill stem tests (DSTs) during appraisal are of particular importance; the production and reservoir data gathered during DSTs help determine commercial viability and support the planning of field development and facilities design. Abu Dhabi Marine Operating Company (ADMA-OPCO) was looking for a solution that allows continuous real-time monitoring and well performance evaluation and ensures that test objectives are being met, thus optimizing the test program for best operational efficiency.

A wireless acoustic telemetry system was chosen and successfully deployed for the first time in several ADMA-OPCO projects to provide surface readout of bottomhole gauge data and two-way communication control of tools, such as test valves, fluid samplers, and perforating guns. With the telemetry system, bottomhole data was rendered available throughout operations, from run-in-hole to well killing operations, and was transmitted along with surface measurements to a data repository that was concurrently accessible to operating company engineers as well as the service company support personnel. The availability of real-time bottomhole pressure and temperature readings at the rig and to offsite engineers for analysis and in-time decision-making ensured that tests were executed in the safest and most efficient way while also maximizing the value of information gathered.

Real-time transmission of test data enabled early diagnostic assessment of reservoir behavior and performance and identified deviations from expected responses as they developed. For example, the expected well response following matrix acid stimulation could be estimated from early prestimulation data, even when the well did not actually achieve stable flow to surface. These early diagnostic data helped to justify running stimulation operations and provided a first reasonable estimate of target rates during the main test sequences as well as the opportunity to continuously update the test plan.

The data available for monitoring and initial interpretation during operations was of equal quality to that gathered by memory pressure recorders, and the use of a flexible data transmission plan focusing on key test sequences provided a descriptive capability equal to that conventionally available only after test completion.

The deployment of surface readout of downhole data combined with real-time data transmission and remote support was performed for the first time in the UAE during those appraisal tests and has since become a standard practice as a result of the operational benefits achieved as well as the enhanced interpretability of data gathered.
A Reliability Based Approach to Assess Pressure Relieving Device Testing Frequency
Authors: Islam Abidul
Published: November 2016

Pressure Reliving Devices (PRD) forms the last line of defenses in a Process Safety system. Their performance is often tested only during the scheduled testing opportunities. A review process of validating the adequacy of the testing frequency is deemed to be of paramount importance from a Process Safety and Integrity perspective. A set of 351 PRD test data from crude unit of three refineries were studied to develop a reliability based model using three different approaches.

Risk based approach using API 581, Normal Exponential Reliability equations and 2 Parameter Weibull Analysis (using industry standard software) were used to calculate the reliabilities of the set of sample PRDs with different testing frequencies and benchmarked against the desired level of reliability.

The testing data of 351 PRD test data were analyased through the three techniques and reliability values calculated. The sample refineries used frequencies of 2, 4 & 5 years and 99% desired reliability. With the sample failure data, the plant using 4 years frequency was be closest to the desired level of Reliability. 2 years frequency was found to be too conservative (over Inspection) while the plant with 5 year frequency showed less then desired level of PRD reliability, thereby compromising Process Safety.

The assessment demonstrated usefulness of normal Exponential equation based calculations, which is reasonably consistent with the complex calculations done through the API 581 or the Weibull Software generated reliability values. It was evident that the Normal Exponential Equation with simple failure rate as the only critical input, was adequately robust to carryout preliminary assessment of adequacy of the PRD testing frequencies. The size and homogeneity of the database is critical in increasing the accuracy of the assessments. This approach would assist scientific validation of PRD testing frequencies. Potential for a software based platform for PDR reliability assessment also is an opportunity.
State-of-the-Art Environmentally Friendly Stimulation Technology Applied on Tight Carbonates on the Black Sea Yields Higher Production Than Expected
Authors: Ulloa Joel , Abdellatif Ibrahim
Published: November 2016

An initiative of a major E&P operator on the Black Sea led to the redesign and optimization of completion and stimulation of important offshore carbonate reservoirs. The wells in this study are characterized by low permeability and heterogeneous properties across the layers. These wells have been producing gas and condensate since the 1990s, and the hydrocarbon production must be maximized.

This paper describes overcoming the challenge of redesigning the stimulation fluid systems to create uninterrupted "wormholes" and remove the damage to improve the productivity of the offshore wells.
The Effectiveness and Evaluation of Road Traffic Accident Reduction Measures in UAE
Authors: Okomgboeso Samuel
Published: November 2016

Objectives/Scope

This paper examined road traffic accident reduction measures in the United Arab Emirates (UAE) between year 2007 and 2011. There are three (3) main objectives of this paper. Firstly, the paper aims to ascertain if the measures put in place by UAE government and other non-governmental agencies (NGOs) towards the reduction of accidents on UAE roads were successful. Secondly, is to investigate why some measures were successful and why others failed. Thirdly, is to establish better ways on how to reduce road traffic accidents in UAE.

Methods, Procedures, Process

Quantitative data was gotten from survey questionnaires sent to 308 people of which 88% of the respondents were drivers and 12% were non-drivers. Qualitative data was gotten from interviews of ten employees of a transport organization in Abu Dhabi. The results of the content analysis of the interview answers were used to triangulate the results from the qualitative data. The UAE RTA statistics gotten was used to compare with the results of the obtained quantitative and qualitative data. Surveyconsole web-based survey software was used to distribute the survey questions. The descriptive analysis method was used to analyse the raw data that it generated.

Results, Observations, Conclusion

The result showed that accident reduction measures put in place in the UAE have been mildly successful and that more work is required to bring down the number of road traffic accidents that occur on UAE roads. The study revealed that persistent adverts utilizing posters and bill boards (in both English and Arabic language) made a significant impact on the drivers while the use of flyers and leaflets made the least impact. RTA adverts that are persistent, constant and persuasive are vital in educating and creating awareness programs on better ways to reduce accidents on UAE roads. This paper advocates for more studies into finding out better ways of educating and communicating road accident reduction messages to the UAE population in order to create the desired personal safety consciousness among drivers. Furthermore, more studies is canvased to ascertain the impact of social culture on drivers’ behaviours and to determine how it can contribute to either an increase or a reduction in RTAs.

Novel/Additive Information

It is considered that the recommendations posited will be used by the transport authorities in the Gulf region to advance their efforts towards achieving their goals with respect to RTA reduction.
Simultaneous Operations For Cantilever Drilling Jack-Ups
Authors: Baan R , van der List R
Published: November 2016

Since the sharp decline in the Oil prices every element in the value chain of producing oil and gas has been looked at in search of reducing cost. It is not so much the end user, the consumer complaining about a too high gasoline price but in general the big hydrocarbon producers fighting over market share with no intention to give in on any gained ground. Apart from that tug of war the US tight oil and Iran upcoming production capacity has made the more than halfed oil price a given which will still last for some time.

To keep the offshore oil and gas industry turning the total well cost equation has more than ever become the key performance indicator for making development and related investment decisions. Oil companies are setting up tenders such to get competitive bids in with the latest equipment. A bottom in dayrates are almost achieved when considering the latest fixutres of the last 6 months as reports from the well established brokers.

Drilling contractors can only compete on price. Efficiency is assumed similar or expected to be reflected in a lower dayrate. Due to the natural resistance of scrapping jack-ups the jack-up portfolio shows a broad band in efficiencies. For example, reviewing the approximately 150 rigs situated in the Middle East the average age is about 22 years with rigs from the early ’70 up to modern rigs just delivered. Still, the spread in efficiency across modern rigs is considerable due to a lack of efficiency drive during the construction boom some years ago.
Using Thomeer Hyperboles for Rocktyping in a Tight Carbonate Reservoir
Authors: Pinto Pedro , Belhaj Hadi , Oriyomi Raheem
Published: November 2016

Rocktyping is a crucial part of static and dynamic reservoir modelling. By grouping together rocks with the same characteristics, models construction is both simplified and improved. Several types of rocktyping techniques exist, focusing on different aspects such as petrophysical properties like porosity and permeability, or sedimentary facies. This paper presents a simple petrophysical rocktyping methodology based on pore size distributions instead or their resulting properties, by using Thomeer hyperboles and multivariate clustering techniques. A set of sixty four Mercury Injection Capillary Pressure curves from a Middle East tight carbonate reservoir were modelled with Thomeer hyperboles and grouped using K-medoids clustering. The number of groups in which to divide the sample was experimented upon by grouping the samples into several numbers of groups and its effects on the saturation model resolution were assessed by the means of the covariance between the original and the grouped dataset. The result of this comparison showed that the ideal number of rocktypes is seven, allowing a good reproduction of saturations in the original dataset and still maintaining a low number of rocktypes which favours dynamic simulation models. The comparison of the grouped data with the petrophysical properties showed that different pore size distributions can yield similar porosity and permeability values, reinforcing the importance of grouping rocks based on pore systems instead of their resulting properties. This method also assists in determining the most relevant samples to define the rocktypes.
Achieving Substantial Cost Savings through a Holistic Asset Replacement Strategy
Authors: Awda H. , Al-Sayed T. , Azouz A. , Al-Hammadi H. , Omar T. , Abdel Hakim M.
Published: November 2016

A holistic asset replacement strategy is developed to produce a master asset replacement plan for a significant number of ageing offshore structures and subsea pipelines in order to meet the business objectives in terms of production from ADMA-OPCO offshore fields over the next 30 years and beyond. The developed strategy follows an integrated approach that covers the entire cycle starting from evaluation and selection, phasing of replacement campaigns and integration with planned development projects. A holistic set of criteria are established for evaluation and selection of asset replacement covering integrity condition (License to Operate), code compliance, technology obsolescence, component replacement, capacity limitation and network optimization.

The developed process for asset replacement master planning is a dynamic and continuous process. The replacement plans are constantly reviewed and updated based on new information and changes in various factors such as business plan, operational requirements, new inspection, technology development etc.

Substantial cost savings can be achieved through developing an integrated asset replacement strategy. The main areas for cost savings include optimization of asset life extension, optimization of CAPEX expenditure associated with asset replacement and optimization of production outage due to asset replacement. The key factors for successful implementation of such a strategy are evaluation of the integrity status of the assets based on an integrated assessment of technical, economic and HSE aspects and optimizing the phasing and integration of the asset replacement campaigns.

This paper presents an integrated asset replacement strategy to achieve substantial cost savings in replacement of ageing offshore structures and subsea pipelines. The key elements and process for developing the asset replacement master plan are presented through a case study. The application of the presented strategy can be extended to other types of oil and gas production assets.
Metal Organic Framework Mixed Matrix Membranes for CO2 Separation
Authors: Anastasiou Stavroula , Bhoria Nidhika , Pokhrel Jeewan , N. Karanikolos Georgios
Published: November 2016

Efficient carbon capture and storage (CCS) approaches are needed to significantly reduce CO2 emissions in the atmosphere. The present work focuses on development of polysulfone (PSF) based mixed-matrix-membranes (MMMs) with Metal Organic Frameworks (MOFs), for enhanced CO2 separation. ZIF-8 synthesized using in-situ hydrothermal method, was incorporated as filler in the polymeric PSF matrix using solution casting. The resulting membranes were characterized for their morphology, structure and stability. The MMMs provide flexibility to effectively tune permeance and selectivity towards acid gas removal by tuning the structure-property relationship of polymer and MOF. SEM, XRD, and FTIR results confirmed that the characteristics of the MOF were preserved in the MMM. The BET surface area of ZIF-8 filler was 1318 m2/g. Based on ongoing work, a suitable combination between the PSF with MOF, and functional amines can open the prospect for efficient MMMs integration towards industrial CO2 capture and separation applications.