A 20 Years Systemic Study of Drilling Practices in a Geothermal Venture Reveals Insightful Findings

2021 ◽  
Author(s):  
Abdullah AlMuhaideb ◽  
Sam Noynaert

Abstract Geothermal drilling has increased in the recent years with the renewable energy initiatives. Geothermal plants provide more than 6% of California's electricity. A large sum from the development budget is consumed by the drilling. This paper systematically analyzes and reviews the drilling activities and operations in a geothermal venture in Hawaii for more than 20 years to enhance the drilling operations and save costs. The paper starts by studying the geology of the area, which is located in an active volcanic region. Then, an extensive data collection was performed that went back to more than 20 years. The data was preprocessed and cleaned to be used in the analysis. The well designs were analyzed and the distribution of the drilling time was determined. After that, the performance of the geothermal drilling was benchmarked with the oil and gas drilling and the geothermal drilling in different parts around the world. The geology of the area is challenging with basaltic formation and tectonic movements. Volcanic eruptions that leads to closing wells were encountered in the recent years. As for the drilling, six challenges were identified and deeply analyzed. These challenges include: lost circulation, stuck pipe, cementing, low rate of penetration (ROP), logistics issues, and safety concerns. Each of these challenges was intensely investigated and solutions were proposed. The benchmarking with the oil and gas industry and other geothermal drilling operations shows that the geothermal drilling operations can be enhanced significantly. This improvement in the drilling in the geothermal venture will result in huge cost savings. A set of recommendations to improve the performance is presented as new organizational and workflow changes, analysis and elimination of nonproductive time (NPT), and novel engineering redesigns.

Author(s):  
Maria V Clavijo ◽  
Adriana M Schleder ◽  
Enrique Lopez Droguett ◽  
Marcelo R Martins

Currently, a Dynamic Position (DP) System is commonly used for offshore operations. However, DP failures may generate environmental and economic losses; thus, this paper presents the Reliability, Availability and Maintainability (RAM) analysis for two different generations of DP system (DP2 and DP3) used in drilling operations. In addition to the RAM analysis, the approach proposed herein considers the uncertainties present in the equipment failure data and provides more information about criticality equipment ratings and probability density functions (pdf) of the repair times. The reliability analysis shows that, for 3 months of operation, the total failure probability of the DP2 system is 1.52% whereas this probability for the DP3 system is only 0.16%. The results reveal that the bus-bar is the most critical equipment of the DP2 system, whereas the wind sensor represents the priority equipment in the DP3 system. Using 90% confidence level, each DP configuration was evaluated for a 1-year operation, finding a reliability mean equal to 70.39% and 86.77% for the DP2 system and the DP3 system, respectively. The DP2 system asymptotic availability tends to present a constant value of 99.98% whereas for the DP3 system, it tends to be 99.99%. Finally, the maintainability analysis allows concluding that the mean time for system repair is expected to be 3.6 h. This paper presents a logical pathway for analysts, operators, and reliability engineers of the oil and gas industry.


2021 ◽  
Author(s):  
Fabio Sawada Cutrim ◽  
Charlton Okama De Souza ◽  
Bruno Sergio Pimentel De Souza

Abstract As a general practice in the oil and gas industry, the well foundation, composed by the conductor and the surface casing, is designed with a strict tolerance regarding cement shortfall on the surface casing. However, in a pre-salt scenario, in order to reduce the costs of well construction, the surface casing shoe generally reaches the top of salt. In this case, it is quite hard to make the cement job reach the mudline due to problems like salt dissolution (generating high calipers) and presence of many geological faults in the post-salt zone (which can work as a lost circulation area). Besides that, an evaluation of the wellhead movement is necessary so that the structural restrictions of subsea equipment connected to the wellhead are not violated. This work had the goal of presenting a coupled structural model to analyze the foundation of a subsea well with a partially cemented surface casing, where the safety factors of surface casing are evaluated in the whole well life cycle along with the wellhead movement due to the loads related to each step of this cycle. A sensitivity analysis on the top of cement (measured from the casing shoe) is made, varying it from 300 m to 800 m. The results showed wellhead movement consistent with what is observed in the field, once no axial movement has been reported. Additionally, it was highlighted that the foundation design depends on the operations during the well construction and its future purpose, production or injection, because the thermal loads associated with operations have different impacts.


2016 ◽  
Vol 56 (2) ◽  
pp. 559
Author(s):  
Brent Steedman

The Australian oil and gas industry is in a period of substantial challenges, including a significant decline in oil prices, fluctuating spot gas prices, a relentless drive for operating efficiency, and tight capital allocation, together with increased regulatory scrutiny and a reputation for below-standards productivity. On the upside, these market challenges provide significant opportunities for companies to bring in new investors, implement new operating models, apply innovation to update processes and practices, and restructure activities. Making material step-changes, requires companies to review, amend, and update joint venture operating agreements (JVOAs). KPMG has worked with many of Australia’s leading oil and gas companies on a range of joint venture engagements. This extended abstract outlines why JVOAs need to be reviewed with respect to the following key opportunities and challenges: Fast-changing global business operating models. Available cost savings by eliminating inconsistent management and operating models between joint ventures. Planning for potential restructuring, including separation of infrastructure (e.g. plants, pipelines, support) from reserve ownership. Sharing of services (e.g. maintenance and logistics) between unrelated joint ventures. Transparency of costs and asset performance. Improved joint venture governance (not more or over-governance) between participants to attract investment. Effective resourcing, noting the right transition of capabilities between deal-makers and joint venture operators. With this extended abstract the authors aim to provide ideas for consideration. Each of these ideas will impact JVOAs. The authors’ proposition is that now is the right time to complete a comprehensive review of JVOAs to enable organisations to move fast as new and innovative opportunities arise.


Author(s):  
Grethe O. Ose ◽  
Trygve J. Steiro

Abstract Integrated operations (IO) is an ongoing change process in the oil and gas industry. New technological opportunities enable working in new ways that involve an integration of onshore and offshore personnel. This paper analyzes the results of two rounds of data gathering in an onshore drilling support center, in terms of the development of resilience. The first round took place in 2004/2005 and the second in 2012. This study presents a framework for the analysis of resilience and has used the case company as a mean of testing the framework. Our findings indicate that the support center has taken a huge step in the direction of becoming more resilient. The drilling company has tested a number of designs and sizes of support centers, each of which has different pros and cons. For the drilling discipline to develop resilience, it is essential that the number of rigs supported by a center is not too large, as they must not become involved in too many rigs and drilling operations. Our findings also indicate that the suggested framework provides a good overall picture of the development of resilience in the case company.


Author(s):  
Ricardo de Lepeleire ◽  
Nicolas Rogozinski ◽  
Hank Rogers ◽  
Daniel Ferrari

Within the oil and gas industry, significant costs are often incurred by the operating company during the well-construction phase of drilling operations. Specifically, the operators cost to drill a well can cost tens or hundreds of millions of USD. One specific area where significant changes in drilling operations have occurred is in the offshore environment, specifically operations from mobile offshore drilling units (MODUs). With the ever-increasing demand for oil and gas, operators globally have increased drilling budgets in an effort to meet forecasted demand. However, the increased budgets are often eroded or offset by increasing drilling costs. Therefore, operators are continually in search of new technology, processes, or procedures to help improve drilling operations and overall operational efficiencies. One Latin America operator identified a common operation as a possible area where operational cost could be easily reduced through the implementation of systems that allow the manipulation of valve manifolds remotely. Additionally, operating such valve manifolds remotely enhanced operational safety for personnel, which was an equally important consideration. This paper details the evaluation of existing equipment and procedures and a process used to develop a new remote-control system using a machine logic control (MLC) that has been designed, built, tested, and deployed successfully on MODUs operating in Latin America.


Author(s):  
Sofia KAFKA

The article deals with the key issues concerning the system of security of fixed assets at the enterprises of the oil and gas industry. The purpose of the article is to investigate the fixed assets features and composition at the the enterprises of oil and gas industry, to determine the approaches to their assessment at the stage of their receipt by the enterprise. The state, dynamics of value and the degree of depreciation of fixed assets in Ukraine for the year 2017 have been analyzed, their features have been distinguished at the enterprises of different branches of the economy. To ensure the effective operation of the enterprises of the oil and gas industry, significant assets are required, and the results of their activities to a large extent depend on the availability and condition of fixed assets that ensure economic sustainability of economic entities. Oil and gas companies include pipelines and related equipment in fixed assets, oil and gas assets, machinery and equipment, buildings, buffer gas, drilling and reconnaissance equipment and other fixed assets. Among the assets of NJSC "NAFTOGAZ OF UKRAINE" for the year 2017, non-current assets occupied 86% of the total assets of the company, of which 94% were fixed assets, what determines the reliability of their accounting as an important element of effective management of enterprises. The dynamics of value and composition of fixed assets of enterprises of the oil and gas industry of Ukraine for 2016-2017 have been determined according to separate economic segments. The cost of fixed assets of NJSC "NAFTOGAZ OF UKRAINE" as of December 31, 2017 amounted to UAH 491 482 million, respectively, according to economic segments, it is structured in such a way that their largest share is concentrated in the system of transportation and distribution of natural gas - almost 48%, for storage of natural gas - 34%, production and sale of natural gas - 12%, and the rest belongs to the economic activities related to oil: the production of crude oil and gas condensate, transportation of crude oil. The composition of fixed assets of extractive enterprises differs from their composition in refineries. Industrial features of mining industry with significant volumes of work related to the disclosure of layers of minerals are characteristic to chemical production with a significant cost of equipment. The main approaches to the evaluation of fixed assets objects at the stage of their entrance to the enterprise have been investigated. The reliability of the accounting information on fixed assets depends on their assessment. When they are received, they are valued at their original cost, that is, by the amount of cash paid or their equivalents or fair value, another form of indemnity granted to obtain the asset at the time of its acquisition or creation, or, if accepted, the amount that is distributed to that asset in the original recognized in accordance with the specific requirements of other IFRSs. After recognition, the entity should choose either a cost model or a revaluation model in its accounting policies and should apply this policy to the entire group of fixed assets. A cessation of recognition occurs after the release of an object or when it does not expect future economic benefits from its use or disposal. In this case, it is recognized as profit or loss.


Author(s):  
Tobiloba Elusakin ◽  
Mahmood Shafiee ◽  
Tosin Adedipe

Abstract With the steadily growing demand for energy in the world, oil and gas companies are finding themselves facing increasing capital and operating costs. To ensure the economic viability of investments and improve the safety of operations, oil and gas companies are promoting their asset integrity management (AIM) systems. In the past, the oil and gas industry adopted reactive maintenance regimes, which involved recertification, testing and repair of faulty equipment while trying to achieve minimum downtime. As technology becomes more affordable, operators have been able to carry out improved fault diagnosis, prognosis and maintenance optimisation. As a result of this, condition-based maintenance (CBM) is being adopted more and more as the preeminent maintenance regime for oil and gas equipment. The blowout preventer (BOP) is one of the most expensive and safety critical drilling equipment in the oil and gas industry. However, there have been very few studies and best practices about how to develop a CBM policy and what specific monitoring techniques and devices will be required to implement it for the BOP system. This paper proposes a V-model based architecture for designing a CBM policy in BOP systems. As a result of the model proposed, gaps in implementation are identified and all the hardware, software and training requirements for implementing the CBM solution in BOP systems will be outlined in detail. Our proposed CBM framework will help BOP operators and maintenance personnel make cost savings through less repairs and replacements and minimal downtime.


2021 ◽  
Vol 11 (5) ◽  
pp. 2157-2178
Author(s):  
David Oluwasegun Afolayan ◽  
Adelana Rasak Adetunji ◽  
Azikiwe Peter Onwualu ◽  
Oghenerume Ogolo ◽  
Richard Kwasi Amankwah

AbstractSuccessful drilling operations are dependent on the properties of the drilling fluid used to drill wells. Barite is used as a weighting agent during the preparation of drilling fluid. Over the years, oil and gas industry in Nigeria has been depending mainly on imported barite for drilling operations, whereas the country has huge deposits of barite. There is the need to assess the properties of the locally sourced barite for their suitability in drilling fluid formulation. This study presents the local processing methods of barite and examines the crude and on-the-site processed barite’s physio-chemical properties. These parameters were compared with American Petroleum Institute and Department of Petroleum Resources standards. XRD results show that on-the-site beneficiated barite has 87.79% BaSO4, 6.66% silica, 0.03% total soluble salt, 1.39% Fe2O3, and 1.603% heavy metals. Chemical analysis indicated that the pH, moisture content, metallic content such as Ca, Pb, Zn, Mg, Cu, and Cd minerals, and extractable carbonates were within the standard specified for usage as a drilling fluid weighting agent. The analysed crude barite samples were basic, within the pH of 8.3 and 8.6. Locally processed barite has lower Fe, Pb, Cd, and Cu content compared to industrially accepted barite. The specific gravity increased from 4.02 ± 0.07 to 4.15 ± 0.13, and the hardness reduced potentially from 5 Mohr to 3.5 Mohr on the hardness scale. The amount of impurities was sufficiently low, and the specific gravity of the samples improved to meet the needs of any drilling operation and compare favourably with industrially accepted barite.


2021 ◽  
Author(s):  
Mario A. Rivas ◽  
Andres A. Ramirez ◽  
Bader S. Al-Zahrani ◽  
Khaled K. Abouelnaaj

Abstract One of the major challenges the Oil and Gas Industry faces nowadays during drilling operations is the twist-offs on Bottom Hole Assembly (BHA) components such as Drilling Jars, Shock Tools, Mud Motors, Roller Reamers, Stabilizers, Drill Collars, PBLs, Heavy Weight Drill Pipe (HWDP), Drill Pipe (DP), etc. To overcome this challenge, an initiative was proposed by performing a study based on twist-offs experienced on BHA components while drilling operations and recommendations are provided to reduce and eliminate twist-offs related to drilling with suboptimal drilling parameters. The statistical data for the twist-off events was collected coming from Daily Drilling Reports, and the analysis was limited to all wells which presented twist-offs on the drillstring and BHA components. Three examples of twist-offs due to drilling with erratic torque are discussed as well as a successful example of drilling parameters optimization. The three examples which presented drillstring and BHA twist-offs were analyzed using available BHA Dynamics and vibrations software and it was discovered that the parameters utilized (operational RPM) fell within the critical zone shearing force peaks (resonance vibrations). The components with the most twist-offs were identified. The hole size where we have the most twist-offs were also identified, which will help in focusing on these areas for the recommendations provided. This analysis will help Drilling Engineers and Foremen to foresee vibration dysfunctions and act accordingly by the use of available BHA Dynamics software in order to optimize drilling parameters before and during drilling. By drilling within a safe operating RPM window (away from resonant RPM), there will be reduction in the number of twist-offs and associated lost time.


2021 ◽  
Author(s):  
Gerard O'Reilly ◽  
Alvin W. Chan

Abstract Depleted Fracture Gradients have been a challenge for the oil and gas industry during drilling and cementing operations for over 30 years. Yet, year after year, problems related to lost circulation, borehole instability (low mud weight due a low fracture gradient), and losses during cementing operations leading to NPT and remedial work continue to rank as some of the top NPT events that companies face. This paper will demonstrate how the geomechanical modeling, well execution and remedial strengthening operations should be implemented to provide for a successful outcome. The use of a Fracture Gradient (FG) framework will be discussed, and the use of a negotiated fracture gradient will highlight how the fracture gradient can be changed during operations. This paper will also show actual examples from Deepwater operations that have successfully executed a detailed borehole strengthening program. Through our offset studies and operational experience, we will provide a format for navigating complex depleted drilling issues and show an example on recovering from low fracture gradients. This paper will demonstrate (1) how our framework facilitated multi-disciplinary collaborative discussion among our subsurface and well engineering communities; (2) how the impacts of drilling fluids and operational procedures can change this lost circulation threshold; and (3) how our negotiated FG approach has successfully delivered wells drilled in narrow margins.


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