SS field is located offshore East Malaysia. 2 exploration wells discovered multiple dipping reservoirs, with oil column of about 40 m. The heterogeneous reservoirs, combined with a very large gas cap (i.e. m size of 2) and moderate aquifer strength impose challenges to maximize recovery from this field. Field development study has formulated 14 horizontal wells with 3 water injectors to achieve recovery factor of 30%. Optimum reservoir management strategy requires a delicate balance of gas cap expansion and water injection drive, where the optimum voidage replacement ratio is only 0.25. However, reservoir dynamic modelling shows that all the wells will get early gas and water breakthrough. ICD technology is therefore evaluated to address the above production and recovery dilemma while prolonging the production life.In this paper, optimization of 12 horizontal ICD wells out of 14 wells will be discussed. This includes the process of qualifying and designing the ICD application in each candidate through static modelling. Full field dynamic modelling was also conducted to quantify the real benefits of ICD, and confirming the robustness of the design throughout field life. In view of high uncertainty of fluid contacts and reservoir quality in unappraised areas, the team has adopted the unique yet challenging approach of field appraisal from pilot holes during the initial implementation stage. This has provided valuable data prior to horizontal drilling and final optimization of ICD. Subsequently, the production performance from the first ICD wells will also be discussed to provide evidence on its effectiveness and lessons learned.Finally, the paper highlights the importance of seamless teamwork and coordination between project team and service providers to deliver superior performance. This can be an informative workflow source for future applicants of such technology with similar fields' nature and risks.

Intelligent Completions (IC) are deployed with the high hopes of frequent data utilization and zonal selectivity maneuver to optimize production continuously. The permanent downhole presence of measurements like pressure, temperature, rate, water-cut, gas-break provide downhole indicators and trending analysis of production performance and injection conformance. These are utilized not only to maximize hydrocarbon production but also to reduce surface handling of water and/or gas, improve injection efficiency, and reduce carbon and environmental footprint. However, the reality could be different from the evaluation stage to the application stage. The asset production engineers or the reservoir engineers face real challenges when it comes to design, downhole installation, data transmission, real-time analysis, and optimization to deliver the real value of the initial investment. These suboptimal application factors, multiplied by the complexity of IC deployment and execution with existing hardware constraints, have limited the progression towards digital well technology. By analyzing such trends, a new advanced completion optimization methodology has been devised, leveraging the latest technology and innovation, IC deployment simplification, and electrification efforts in the industry. This paper analyses the underutilization reasons of digital well technology, such as - the ability of design and implementation, the downhole data measurement, complexity of modeling and optimization, and the bottlenecks in applying the learning from the Intelligent Completions data to optimize production. It is then compared to the easing transition to the future digital-wells, advanced modeling capabilities that are driving the oilfield digitalization by next-generation Intelligent Completion. This digital transition ranges from ease-of-deployment to ease-of-optimization and eventually towards cloud-enabled decision making. The new era of IC electrification deployment and digital solutions are twinning to provide an integrated platform to maximize value and justification for more future digital wells. A fully digital system to control reservoir and optimize the product is becoming a reality with the transformation of modeling capability and enabled by simplification of IC deployment, and this is the digital future of IC optimization. This digital solution is continuously feeding asset subsurface, modeling, and optimization team with productivity or injectivity indexes and other inputs required for reservoir steady-state and transient evaluation. The IC industry continues to be integrating into the new solution frontiers of logging-while-producing, the testing-while-producing capability to the eventual optimizing, modeling-while-producing future, leading towards a true digital oilfield of the future.

The horizontal wells side-track campaign at CACT’s H fields in South China Sea has been very successful and challenging over the last two years. Horizontal wells are well-recognized in developing thin-oil column within multi-stacked reservoir by exposing wellbore to maximum reservoir contact and drainage area. The lateral targets and remaining oil reserves are in attic thin oil columns in clean sands and shaly sands. Since the oil column is thin at the top of a clean sandstone reservoir with strong bottom water drive, early water break through can occur even when the lateral is well placed on the top of the reservoir. To further optimize the reserves recovery, horizontal trajectories are placed near the top of the reservoir, and the well is completed with stand-alone screen combines with downhole inflow control devices (ICD’s). This combination provides the horizontal well optimum completion for draining and further prolongs the life of the well. The application of the field-adjustable nozzles based on real-time Logging-while-Drilling (LWD) data updates into ICD’s predrilled model, together with the precise well placement have enabled horizontal wells to be economically developed in a thin oil-bearing layer. In this paper, some of the technical assessment and collaboration workflow between the multi disciplinary team of technology users and service providers, enrooting to the successful implementation of the first nozzle-type ICD’s installation and Distance-to-Boundary Well Placement technology in China will be highlighted. The success of the first ICD’s well completions installation was proven with better Productivity Index (PI) based on initial well performance. The first ICD’s well produced ~100% oil for almost two months since early Mar 2009. Meanwhile, a second ICD’s well with thinner net oil pay produced 100% oil for 20 days clearly showed the benefit of ICD later when water break through and increased to 85%. The mentioned integrated Nozzle-ICD’s design with precise Distance-To-Boundary Well Placement solution have shifted the conventional application of ICD’s, which is hardware-orientated, from being dictated one-way by hardware supplier, towards a holistic reservoir-centric design. It has become an operation that keeps all-party informed and always in communication. The "real-time" add-value of LWD and well placement data in updating the predrilled ICD’s well model has benefitted horizontal wells inflow control design. This integrated and reservoir-centric solution has optimized horizontal well application successfully in one well, but facing some reservoir and structural challenges in another well; which has provided valuable lesson-learned for future drilling.

The 'S' field, located offshore East Malaysia, consists of multiple-dipping heterogeneous sandstone reservoirs with unconsolidated formation. These multi-stacked reservoirs have an overall 40m thick oil column with marginal Oil-Initial-In-Place (OIIP). A large gas cap, i.e. twice the OIIP equivalent, also exists. Scenarios of zonal gas-out leaving huge oil bypass and moderate aquifer strength with inevitable water invasion cautioned the asset team to consider intelligent zonal flow control especially in its horizontal producing wells.Two of the 14 horizontal producer wells in this marginal field have been screened to apply the modular integrated intelligent completions system (IICS) to actively control and permanently monitor zonal inflow for optimal production. Future selective production control and data surveillance enabled by the IICS are essential to fulfill the needs for delicate downhole zonal flow balance for ultimate oil incremental and recovery. It provides control against the aggressive gas cap expansion at the heels while addressing the moderate aquifer coning-up problems from the dipping toes as the field depletes. This paper highlights the successful implementation of the next generation intelligent completions system in a complicated, highly-dipping, multi-layered sandstone reservoir with commingled production. In this multi-zonal production solution, the conventional surface-controllable downhole zonal flow control valves are now integrated with data surveillance gauges, intelligent sensors and isolation packers all into one single completion joint, instead of the precedent multi-joints system (i.e. splicing required up-to 3 joints per zone conventionally). This single modulated joint system has reduced installation time substantially in comparison to conventional intelligent completions installations. The risk of surface completions make-up damage before run-in-hole is also greatly reduced with less connecting components. This robust yet compact system has made on-site completions tally adjustment easier and is enabled with LWD data update while drilling. As a result, intelligent completions design becomes more flexible and responsive to actual reservoir challenges and drilling surprises -providing an all together "intelligent" solution.This paper also discusses the screening process from simulation performed for candidate evaluation to the resulting impact on production post-installation. Future applicants of such technology with similar fields' nature and risks can benefit from the discussed lesson-learnt; best-practice workflow and seamless teamwork and coordination between the project team and service providers in delivering an advanced fit-for-purpose solution.

The first horizontal oil well was drilled through an anticline structure in the Block-7E of East Flank, S-field, penetrating three production sands Sand I, Sand II and Sand III. Based on a comprehensive pre-drill study through steady-state and 3D dynamic time lapse simulation, Inflow Control Device (ICD) with integral sleeve (on/off function) attached to the ICD's joint is the optimum development of the fault block that maximizes zonal control for contrasting water encroachments. Due to the unconsolidated nature of the target reservoir, this well is designed for Open-Hole Gravel Pack (OHGP) with specialty 3D filtration screen to manage sanding issue. This paper highlights 2-in-1 application of ICD with enabled zonal shut-off sleeves and the OHGP completions with external screen. A pre-drilled ICD dynamic modeling is constructed to evaluate the well performance with ICD configuration. The design criteria for an optimum ICD design configuration is based on number of compartments and size, packer placement, ICD nozzle sizes and numbers. This dynamic single well model was used to justify the technology value which resulted in production improvement (maximizing oil and minimizing/delaying water). However, during the drilling of this well, the pre-drilled model is then updated in real time with the input of actual petrophysical data from Logging While Drilling (LWD) measurements along the OH section. Actual well trajectory and structure adjustment encountered while drilling were also co-utilized to determine the final optimum ICD design for the field run-in-hole (RIH) completion. Target fault block in S-Field East Flank requires optimum development strategy for its economic viability (Kumaran, P. N et al. 2017). Only one open-sea discovery well proved the oil bearing sands to-date, but a lot of uncertainties remains: geological structure, fluid contacts, fluid characterization, existence and nature of an aquifer, etc. Hence, all these uncertainties are incorporated in the ICD optimization through sensitivity analysis and uncertainty range estimation. Oil production improvement with water reduction while delaying water encroachment are key in the optimization of the ICD design, which is achieved by evaluating the impact of ICD's influx balancing throughout the horizontal section. Study shows that water encroachment is effectively controlled with 9 compartmentalization zones along the horizontal section, each one separated using oil swellable packer. After 7 months of stable flow, well test is showing zero-water and zero-sanding to surface with well controlled production rate that can produce more if required. This is the testimonial of the deployment success from its initial conceptual design to its ultimate completion.