In a giant offshore UAE carbonate oil field, challenges related to advanced maturity, presence of a huge gas-cap and reservoir heterogeneities have impacted production performance. More than 30% of oil producers are closed due to gas front advance and this percentage is increasing with time. The viability of future developments is highly impacted by lower completion design and ways to limit gas breakthrough. Autonomous inflow-control devices (AICD's) are seen as a viable lower completion method to mitigate gas production while allowing oil production, but their effect on pressure drawdown must be carefully accounted for, in a context of particularly high export pressure. A first AICD completion was tested in 2020, after a careful selection amongst high-GOR wells and a diagnosis of underlying gas production mechanisms. The selected pilot is an open-hole horizontal drain closed due to high GOR. Its production profile was investigated through a baseline production log. Several AICD designs were simulated using a nodal analysis model to account for the export pressure. Reservoir simulation was used to evaluate the long-term performance of short-listed scenarios. The integrated process involved all disciplines, from geology, reservoir engineering, petrophysics, to petroleum and completion engineering. In the finally selected design, only the high-permeability heel part of the horizontal drain was covered by AICDs, whereas the rest was completed with pre-perforated liner intervals, separated with swell packers. It was considered that a balance between gas isolation and pressure draw-down reduction had to be found to ensure production viability for such pilot evaluation. Subsequent to the re-completion, the well could be produced at low GOR, and a second production log confirmed the effectiveness of AICDs in isolating free gas production, while enhancing healthy oil production from the deeper part of the drain. Continuous production monitoring, and other flow profile surveys, will complete the evaluation of AICD effectiveness and its adaptability to evolving pressure and fluid distribution within the reservoir. Several lessons will be learnt from this first AICD pilot, particularly related to the criticality of fully integrated subsurface understanding, evaluation, and completion design studies. The use of AICD technology appears promising for retrofit solutions in high-GOR inactive strings, prolonging well life and increasing reserves. Regarding newly drilled wells, dedicated efforts are underway to associate this technology with enhanced reservoir evaluation methods, allowing to directly design the lower completion based on diagnosed reservoir heterogeneities. Reduced export pressure and artificial lift will feature in future field development phases, and offer the flexibility to extend the use of AICD's. The current technology evaluation phases are however crucial in the definition of such technology deployments and the confirmation of their long-term viability.

Abu Dhabi National Oil Company (ADNOC) is expanding the use of DIAL (Digital Intelligent Artificial Lift) technology, across its assets, through a range of different oil production applications. These include gas lifted single and dual completions, Extended Reach Drilling (ERD) wells and In-Situ gas lift. DIAL is a first-of-kind technology that enhances the efficiency of gas lift through downhole data, surface control and digital operations. This data driven approach enables production automation and minimizes well intervention requirements. This paper will present four different applications for the technology. These applications were selected by ADNOC assets, as they were deemed to bring the most value for DIAL implementation. The paper will describe technical details for each application, including gas lift designs, completion specificities, installation procedures and benefits observed or anticipated. A summary of the value add for each of the four applications are listed below. Gas lifted single completion is the most common application for the DIAL system. The benefits of the application have been described in previous papers and range from intervention savings to production optimization. This paper will highlight the additional benefit of automation, making full use of the system digital features. Gas lifted dual string completion, where the technology enables efficient lift of both strings, improving well production in the range of 40 to 100%. API (American Petroleum Institute) does not recommend pressure operated gas lift in dual wells. DIAL offers stability, simultaneous lifting of both strings through surface control and downhole data. ERD gas lifted well required flexibility for its gas lift operations. DIAL enables real time changes of injection depths based on reservoir response, and units can be installed deeper into the deviated section of the well without any deviation limits. In-Situ gas lift is a specific application where a gas zone is used to lift production from the oil zone in the same well. DIAL enables measurement of the gas injection rate at the point of injection, and adjustment of the flow area to optimize production. This is a world's first use of the technology for this type of application. A range of applications are described in this paper with many technical details, recommendations and lessons learnt to enable replication within the industry. Some of these applications are world first.

A major Abu Dhabi oil and gas producer targeted an increase in production from their major offshore oilfields. Better optimization of the reservoir through advanced well architecture was considered an option. One way to achieve this objective was through accessibility and hydraulic control of all horizontal drains. Multilateral technology is commonly used to increase the production per well and reduce drilling time while optimizing production facilities. The project targeted multiple reservoirs with two separate laterals to meet reservoir requirements. The application required individual through tubing access for intervention into each lateral. Multilateral technology has been traditionally limited to commingled production with limited or no access to the laterals. To help address and overcome these challenges, the operator planned and installed their first Level 5 multilateral tieback system (MLTBS).

Field presented here is located in the southern part of the Arabian Gulf approximately 135 km north-west of Abu Dhabi city. This giant heterogeneous carbonate field consists of multi-stacked reservoirs. The presented reservoir is highly fractured, it measures 9 km by 11.5 km. The reservoir has an original oil in place estimated at 2,240 MMstb of 35°API oil with saturation gas of 400 SCF/bbl. The reservoir pressure is +/− 2,700 psi and the sealine pressure in the field is +/− 1100 psi. The wells completed in T reservoir are unable to flow naturally against the high sealine pressure. Some wells are producing against by-pass line at 600 psi. Crestal gas injection was introduced to maintain the reservoir pressure. To produce the reservoir at its potential, it is required to use some artificial lift techniques. ESP was finalized to install for overcoming the high sea line pressure. As mentioned earlier the T reservoir is naturally fractured and has crestal gas injection, which lead towards 3,500 – 4,000 SCF/bbl and beyond the ESP limit. This requires some solution to handle the gas. A collaborative team of engineers was assigned to design and meet the challenge of such a premier application. The team conducted a detailed and comprehensive analysis of the T reservoir's fracture and fault characterization: the aim was to deliver an optimal well design meeting the requirement of ESP gas handling with minimum cost. A unique, fit-for-purpose dual completion (4-1/2" × 2-3/8") was finalized. The rigless ESP will be run through 4-1/2" tubing and 2-3/8" tubing will be utilized for gas handling and re-injecting gas in the sealine at surface. The dual completion will allow to handle high GOR through short string, which will lead towards the long ESP runlife. Before commencing the full development plan for T reservoir, this will be a pilot for better understanding the reservoir and its behavior. Rigless ESP was selected due to the advantages compared with conventional ESP: POOH and RIH of retrievable ESP parts through a conventional slickline unitPumps can be replaced during the well life without rig workover.Low OPEX cost.

The giant heterogeneous carbonate field presented here consists of multi-stacked reservoirs and is located in the Arabian Gulf approximately 135 km north-west of Abu Dhabi. The reservoir named "T" measures 9 km by 11.5 km, with large accumulation of 35 °API oil with initial gas oil ratio of about 400 scf/STB. The current reservoir pressure is around 2,700 psi; many of wells are unable to flow naturally against the high sealine pressure, due to low productivity and relatively low GOR. To produce these wells, "artificial lift" or lower sealine pressure are required. A collaborative team of Reservoir Engineers, Petroleum Engineers and Geoscientists was assigned to find a sustainable and cost-effective solution to produce reservoir "T" in order to evaluate its potential. The team conducted a detailed and comprehensive study of the field starting from reservoir "T" and then expanded to the other reservoirs. As a result, the proposal of an "Auto Gas Lift" (AGL) pilot was formulated to use gas from the reservoir "C" (underlying reservoir T) to artificially lift the oil produced from reservoir T. AGL is a cost-effective artificial lift system, directly replacing for conventional gas-lift equipment, gas compression facilities, gas transport pipelines and ancillary equipment. This technique has been identified as the most suitable for such mature offshore field, where existing platforms have limited spare load and space capacity and could not accommodate gas-lift compression facilities or ESP topside equipment. The first pilot completion has been designed. It consists of a perforated downhole high GOR zone from which gas is bled into the tubing at a rate controlled by a downhole gas lift valve. The gas produced from high GOR reservoir C will allow reservoir T to flow by reducing the hydrostatic head of the fluid column in the well. Artificial lift has not been implemented yet in the field. However, several artificial lift techniques, such as Electrical Submersible Pumps or conventional gas lift, are foreseen in long term development plans. "AGL" technique, if successful, could represent a cost-effective solution for further appraisal of this reservoir, without waiting for the implementation of large-scale artificial lift techniques.