Layer | Fill | Outline |
---|
Map layers
Theme | Visible | Selectable | Appearance | Zoom Range (now: 0) |
---|
Fill | Stroke |
---|---|
Collaborating Authors
_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 211570, “Maximizing Reserves Value Using Multilateral Wells: A Decision Support Tool and Key Applications,” by Eglier Yanez, SPE, Luigi Saputelli, SPE, and Fahad Alhosani, SPE, ADNOC. The paper has not been peer reviewed. _ In the complete paper, the authors review advances in selected completions to provide insight into adoption of multilateral technology (MLT), including lessons learned and recommendations. Six demonstrative applications were reviewed to validate technical assumptions for selecting particular MLT concepts. The authors write that MLT completions can reduce between 10 and 30% of drilling and completion (D&C) cost requirements while enhancing field-development net present value (NPV) in the range of 1–21%, with the potential of promoting fields that were otherwise uneconomic. This synopsis is devoted to the authors’ proposed technoeconomic assessment of MLT. Part 1: Economic Assessment of Dual and Trilateral Wells A simplified performance assessment was conducted to determine the economic effect of adding multilateral wells into a particular development plan. In this case, the following four well configurations or well types were considered: - Two single-lateral horizontal wells - One dual-lateral well with independent access to each lateral - Three single-lateral horizontal wells - One trilateral well completed with single controlled, commingled completion This analysis aims to produce insights from the following two comparison cases: - Comparison 1: Two single horizontal wells vs. one dual-lateral well - Comparison 2: Three single horizontal wells vs. one trilateral well The well design assumed for the cases can be found in the appendix of the complete paper. The production and reserves drained are maintained the same for each of the laterals; thus, those are considered controlled variables. To understand the effect of adding laterals to a motherbore, three cases have been selected for each of the previously mentioned well configurations by varying drilling depths for each typical cost environment to specify the areas with more potential for multilateral application and, conversely, the areas where single wells might appear to be more convenient. The analysis is broken down into onshore and offshore-shallow-water environments, where the main difference is the drilling cost per foot. The three cases are as follows: - Short-footage well: Motherbore depth of 5,000 ft and lateral length of 4,000 ft - Medium-footage well: Motherbore depth of 7,000 ft and lateral length of 8,000 ft - Long-footage well: Motherbore depth of 9,000 ft and lateral length of 12,000 ft The well costs considered for the study can be seen in Tables B-1 and B-2 of the appendix. In this simplified example, the capital costs included are limited to well-construction costs. Every lateral has a post-stimulation initial rate of 800 STB/D, which is expected to accumulate approximately 1.5 million STB on a 20-year horizon (Fig. 1). One should assume that, in this case, the equivalent rate of the dual-lateral well is exactly double of the one horizontal well and that of a three-lateral well is triple of one horizontal well.
Abstract Drilling several branches into a reservoir from a main wellbore (multi-lateral/multi-branch wells) offers potential benefits in terms of improving drainage, productivity and well economics. This technique has become increasingly popular since the 1990's to the extent that multi-lateral/multi-branch well technology has now become one of the most important innovations within the oil industry. In the paper, the authors review and summarize multi-lateral/multi-branch wells as a development option for oil and gas fields. The process of screening multi-lateral/multi-branch wells applications is discussed, identifying not only the potential benefits of economics and efficient access to reserves, but also the risk associated with both the reservoir application and mechanical systems. Emphasis is placed on providing guidelines for each stage of this evaluation and design processes for these wells, incorporating a multi-disciplinary understanding of the reservoir geology, reservoir dynamics, completion design and operational management of the well. The importance of contingency planning in the process is highlighted, as a means of risk management. Introduction The application of horizontal wells in developing oil and gas fields has dramatically increased and become increasingly important in recent years. The Technology Research Center of Japan National Oil Corporation and The Horizontal Well Technology Unit at Herriot-Watt University initiated in 1993 a collaborative work program for study of horizontal wells. The objectives of this work program were to review and analyze strategically important well technologies, with a view to developing a framework for optimum selection and design progress. The initial phase of work addressed horizontal well issues and their application, resulting in the publication of a Design Guide Book in 1994. An extension of the work was formulated to address multi-lateral/multi-branch wells which have a potentially important role in current, new and existing oilfield developments, and which are rapidly becoming an accepted technology for developing oil and gas reservoirs world wide. They may also promote a reduction in well numbers, and improvements in both productivity and ultimate recovery leading to enhanced economics in both new and mature fields. The rapid evaluation of multi-lateral/multi-branch wells promoted the study which was initiated in 1995 and published in 1996. A database of multi-lateral/multi-branch wells worldwide was compiled and a strategy for the planning and design of multi-lateral/multi-branch wells was encapsulated in tabular and flow chart format in the study. Summary results of this study follow in the remaining sections of this paper. What are Multi-Lateral/Multi-Branch Wells? This chapter examined the definition and the multi-lateral/multi-branch configuration options which are currently available and emphasized the economic and technical benefits which can be derived from their application. P. 135^
- North America > United States (0.46)
- Asia > Middle East (0.28)
- Asia > Middle East > Saudi Arabia > Saudi Arabia - Kuwait Neutral Zone ("Partitioned Zone") > Arabian Gulf > Arabian Basin > Arabian Gulf Basin > Khafji Field (0.99)
- Asia > Middle East > Kuwait > Saudi Arabia - Kuwait Neutral Zone ("Partitioned Zone") > Arabian Gulf > Arabian Basin > Arabian Gulf Basin > Khafji Field (0.99)
Efficient and Reliable Multilateral Coiled Tubing Intervention Technique for Acid Stimulation: A Case History in the Middle East
Alnasser, Hassan Basim (Baker Hughes) | Okeke, Ugochukwu Maria (Baker Hughes) | Zhang, Zhiheng (Baker Hughes) | Veen, Ronnie Van Der (Baker Hughes) | Chishti, Sadaf Shoukatali (Baker Hughes) | Umirshin, Saken (Baker Hughes)
Abstract In recent years, multilateral wells have become more predominant enabling either improved recovery or injectivity depending on the well type. The process of timely accessing the correct lateral with coiled tubing (CT) is still one of the greatest challenges relative to the well intervention. This paper presents a case history in which a flawless 2.375-in CT intervention was performed to stimulate laterals with a proprietary multilateral entry bottom hole assembly (BHA) that steered the CT efficiently into the laterals. The injector well has a natural and un-natural lateral, both of which required stimulation. A proprietary hydraulic multilateral entry tool was selected for the job which reliably locates and enters multiple lateral junctions in a single run. The special working mechanism of the tool circumvents any need for an electrical control or steering system. Along with this tool, a casing collar locator (CCL) was incorporated into the BHA, powered by a proprietary CT conductor telemetry system. Real time data enabled confirmation relative to access into the correct lateral to save time without the need to tag the bottom. A gamma ray (GR) sub can also be incorporated into the BHA to correlate depth where needed. A major challenge for multilateral intervention is time on location. The multilateral entry tool searches for the lateral by rotating 360° until it reaches the desired kick off angle which is confirmed by a surface pressure indication signifying that the correct lateral has been located. The simple yet effective operational mechanism of the multilateral tool allows each lateral to be found and entered in less than 30 minutes once it is positioned at the window. Depth correlation is confirmed with use of either the CCL or GR subs or a combination of the two and the multilateral entry tool is resettable easily by pressurizing, which enables any number of laterals to be located & stimulated. The job was completed safely as per program with more than 4,000 bbl of acid pumped to stimulate both the laterals. The entire operation was conducted efficiently, flawlessly, and post injectivity results of the stimulation resulted in significant incremental injection drainage capability. This combination of BHA's options and the efficient mechanism of the multilateral entry tool to find and enter multiple laterals quickly and reset without the need to pull out of hole, enables the Operator to intervene in any number of branches of a multilateral well in a timely and efficient manner. This is a very important case history for other complex multilateral wells in the region which could benefit from this technology and approach
- Asia > Middle East > Saudi Arabia (0.68)
- North America > United States > Texas (0.47)
Abstract Multilateral wells have been proven over decades and have developed into a reliable and cost effective approach to mature field rejuvenation and extended commercial viability. This paper will discuss case studies demonstrating a number of techniques used to create infill multilateral wells in existing fields with a high level of reliability and repeatability. Techniques reviewed will cover cutting and pulling production casing to drill and case a new mainbore versus sidetracking and adding laterals to an existing mainbore. Discussion will also cover completion designs that tie new laterals into existing production casing providing significantly greater reservoir contact. Temporary isolation of high water-cut laterals brought into production later in the well's life through bespoke completion designs will also be discussed. Case studies will include discussion of workover operations, isolation methods, and lateral creation systems. Where available, resulting field performance improvements will also be discussed. In Norway, slot recoveries are commonly performed by cutting and pulling the 10-3/4" casing, redrilling a new mainbore, and running new casing. This enables junction placement closer to unswept zones and easier lateral drilling to targets. It does have drawbacks, however, related to the additional time required to pull the subsea xmas tree and challenges associated with pulling casing. In 2019, Norway successfully completed a 10-3/4" retrofit installation, whereas a sidetrack was made from the 10-3/4" and an 8-5/8" expandable liner was run down into the reservoir pay zone where two new laterals were created. The 8-5/8" liner saved time otherwise spent having to drill the section down to the payzone from the laterals. These wells have a TAML Level 5 isolated junction, Autonomous Inflow Control Devices (AICDs) in each lateral, and an intelligent completion interface across the junction, enabling active flow management and monitoring of both branches. In Asia, infill laterals were added to existing wellbores by sidetracking 9-5/8" casing and tying production back to the original mainbore. These dual laterals were completed with intelligent completions to enable lateral flow management and monitoring of both laterals. In Australia, dual laterals were created in a similar fashion; laterals are added to existing wells; however, a novel approach was used to manage water from existing lower mainbore laterals whereby they are shut in at completion and opened later when the new lateral is watered out. The older lateral now produces at lower water cut given the time allowed for water coning in the lateral to relax. Using this practice, production is alternated back and forth between the two laterals. In the Middle East, an older well has been converted from TAML Level 4 to Level 5 in order to prevent detected gas migrating into the mainbore at the junction. This conversion of a cemented junction well has enabled production to resume on this well. The well was converted to incorporate an intelligent completion to enable flow control of each lateral. This paper intends to provide insights into the various mature field re-entry methods for multilateral well construction, and a review of the current technology capabilities and well designs through the review of multiple case histories.
- Oceania > Australia > Western Australia > North West Shelf > Carnarvon Basin > Exmouth Basin > Kangaroo Trough > Block WA-35-L > Novara Field (0.89)
- Oceania > Australia > Western Australia > North West Shelf > Carnarvon Basin > Exmouth Basin > Kangaroo Trough > Block WA-155-P1 > Novara Field (0.89)
- Oceania > Australia > Western Australia > North West Shelf > Carnarvon Basin > Exmouth Basin > Block WA-44-R > Coniston Field (0.89)
- (3 more...)
Identify and Recommend High-Value Improvement Opportunities in a Geologically Challenging Reservoir
Al Dhanhani, Helal (ADNOC Offshore) | Fazal, Ayub (ADNOC Offshore) | Selvam, Balakrishnan (ADNOC Offshore) | Obeta, Chukwudi (ADNOC Offshore) | Herrmann, Rolf (ADNOC Offshore) | Kosik, Ivan John (ADNOC Offshore)
Abstract This abstract proposes an optimum plan for offshore Abu Dhabi carbonate reservoir capitalizing on all historic and ongoing lessons learned and defining clear actions, pilots and completion technologies to achieve and sustain desired production target. Different completion designs will be discussed in this paper to define the optimum completion strategy per well and area. The completion designs were as follows: Single completion with 10000ft (10k') lateral length Tri lateral with 10k’ branch (total 30k') Fishbone with 6×6k’ branches (total 18k') Long standing strategy to develop this reservoir with line drive depletion. The base plan is to drill a single lateral with 10k’ lateral length and 1 km spacing with a plan to convert the base producer to an injector while the line drive spacing is downsized to 500m. The total footage of reservoir contact in this case is 10K’ in base case followed by 20K’ in the infill timing. The other completion designs are suggested to increase the reservoir contact at initial times to reduce the pressure drawdown in the production wells. Fishbone consists of a cemented motherhole with 6 branches 3K’ laterals at 30° angle (total footage ~18K'). Another completion design is the tri-lateral which consists of three branches parrelel to each other with reservoir contact ~30K'. The conversion strategy is not possible by the application of multilateral production wells due to the wellbore collision concern with infill drilling adjacent to multilateral wells. Note that branches in the fishbone and tri-lateral well designs are left as open hole due to liner access concern. For production performance comparison, due to well management logic of the model it was necessary to normalize the individual well profiles to attain an equivalent online date and equivalent amount of production days. The objective of normalization was to provide a fair and unbiased comparison of the competing completion types. Calculation of the net present value (NPV) and comparing it for each well while taking into consideration the cumulative oil recovery results in a hybrid development scenario with preferred multilateral and preferred Monobore development wells. The dynamic model results were used to compare well by well the cum recovery and the NPV, which led to create an economical development scenario without jeopardizing the ultimate recovery.