Energy storage systems for drilling rigs

Energy storage systems are an important component of the energy transition, which is currently planned and launched in most of the developed and developing countries. The article outlines development of an electric energy storage system for drilling based on electric-chemical generators. Description and generalization are given for the main objectives for this system when used on drilling rigs isolated within a single pad, whether these are fed from diesel gensets, gas piston power plants, or 6–10 kV HV lines. The article studies power operating modes of drilling rigs, provides general conclusions and detailed results for one of more than fifty pads. Based on the research, a generic architecture of the energy storage module is developed, and an engineering prototype is built. The efficiency of using a hybrid energy accumulation design is proven; the design calls for joint use of Li-ion cells and supercapacitors, as well as three-level inverters, to control the storage system. The article reviews all possible options for connecting the system into a unified rig power circuit, and the optimum solution is substantiated. The research into the rig operating modes and engineering tests yielded a simplified mathematical model of an energy storage unit integrated into the power circuit of a drilling rig. The model is used to forecast the payoff period of the system for various utilization options and rig operating modes. The findings of this study can help to better understand which type of storage system is the most efficient for energy systems with temporary high load peaks, like drilling rigs.

Methodology for Assessing the Stability of Drilling Rigs Based on Analytical Tests

Underground mining machines, such as wheel-tyre drilling rigs, are articulated and equipped with booms that project far beyond the undercarriage. Such a structure makes these machines prone to losing stability. Hence, it is necessary to analyse the distribution of masses and geometry as well as their broadly understood stability during the entire design process, taking into account many factors resulting from the manner and conditions of their operation. However, there are no appropriate computational models that would enable analytical tests to be carried out for machines with this kind of construction. This article is concerned with the author’s computational model, which allows the stability of single- and twin-boom drilling rigs to be quickly assessed. The model makes it possible to perform analyses without having to solve differential equations that are present in dynamic models or using specialist software based on CAD and CAE tools. The developed model allows determination of the pressure of wheels and jacks as a function of many important parameters and variables. Additionally, the distances of the centre of gravity from the tipping edge are calculated. The developed computational model was verified by comparing the obtained results with the results of the full dynamic model, the results of model tests carried out in the CAD/CAE program, and the results of empirical tests of wheel and jack pressures on the ground for the selected drilling rig. The model was subjected to verification and validation, which proved that it was fully correct and useful. The model was used to prepare a practical and user-friendly calculation sheet. Apart from the numerical values, the calculation sheet contains a graphical representation of the machine, the location of the centre of gravity, the tipping edges, as well as graphs of the wheel and jack pressures. Next, analytical tests of the stability of the selected drilling rig were carried out. The obtained calculation results are consistent with the results of empirical research. The computational model and the spreadsheet provide handy tools used during the design process by one of the Polish company’s producing drilling rigs.

Seismic-while-drilling by drill-bit source and large-aperture ocean-bottom array

Seismic while drilling (SWD) by drill-bit source has been successfully used in the past decades and is proven using variable configurations in onshore applications. The method creates a reverse vertical seismic profile (RVSP) dataset from surface sensors deployed as arrays in the proximity of the monitored wells. The typical application makes use of rig-pilot reference (pilot) sensors at the top of the drill-string and also downhole. This approach provides while-drilling checkshots as well as multioffset RVSP for 2-D and 3-D imaging around the well and prediction ahead of the bit. For logistical (sensor deployment) and cost (rig time related to technical installation) reasons the conventional drill-bit SWD application is typically much easier onshore than offshore. We present a novel approach that uses a network of passive-monitoring sea bottom nodes pre-deployed for microseismic monitoring to simultaneously and effectively record offshore SWD data. We study the results of a pilot test where we passively monitored the drilling of an appraisal well at the Wisting discovery in the Barents Sea with an ocean-bottom cable deployed temporarily around the drilling rig. The continuous passive recording of vibration signals emitted during the drilling of the well provides the SWD data set, which is treated as a reverse vertical seismic profile. The study is performed without rig-pilot signal. The results are compared with legacy data and demonstrate the effectiveness of the approach and point to future applications for real-time monitoring of the drilling progress, both in terms of geosteering the drill bit and predicting formation properties ahead of the bit by reflection imaging.

Internet of Things IoT Edge Computer Vision Systems on Drilling Rigs

This study focuses on the design and infrastructure development of Internet-of-Things (IoT) edge platforms on drilling rigs and the testing of pilot IoT-Edge Computer Vision Systems (ECVS) for the optimization of drilling processes. The pilot technology presented in this study, Well Control Space Out System (WC-SOS), reduces the risks associated with hydrocarbon release during drilling by significantly increasing the success and time response for shut-in a well. Current shut-in methods that require manual steps are prone to errors and may take minutes to perform, which is enough time for an irreversible escalation in the well control incident. Consequently, the WC-SOS enables the drilling rig crew to shut-in a well in seconds. The IoT-ECVS deployed for the WC-SOS can be seamlessly expanded to analyze drillstring dynamics and drilling fluid cuttings/solids/flow analysis at the shale shakers in real-time. When IoT-ECVSs communicate with each other, their value is multiplied, which makes interoperability essential for maximizing benefits in drilling operations.

Retrofitting Offshore Drilling Rigs with Islanded DC Grids and Energy Storage

The paper presents a novel approach for modernizing/retrofitting offshore drilling rig power plants with islanded direct current (DC) power grids and energy storage. The concept has been successfully applied on several offshore rigs which are in operation today and is applicable to jack-ups, semi-submersibles, drill ships, as well as other types of marine support vessels for oil and gas platforms and wind farms. The approach aims to enhance the feasibility of leveraging energy storage solutions on offshore drilling rigs and marine vessels by making use of the existing power plant footprint. Unique measures have also been incorporated into the electrical system architecture to ensure that the reliability and safety of the existing alternating current (AC)-based system are not compromised. This enables operators to capitalize on the numerous benefits of energy storage (e.g., reduced emissions, enhanced dynamic performance for drilling and dynamic positioning, etc.) without having to perform a "rip and replace" of the entire power plant and electrical infrastructure.

World's First Successful Coiled Tubing Intervention to Stimulate Four Laterals in a Single Trip

Drilling a multilateral well is generally recommended for several reasons such as achieving higher productivity indices and improving recovery in tight, low-permeable zones. While the many benefits of multilateral wells are attractive, they also have drawbacks which make these wells challenging. A key challenge is how to effectively stimulate all the laterals after they have been drilled. This paper presents the application of a unique intervention technique in a multilateral well to stimulate several laterals in a single run. To increase reservoir contact area the operator drilled a multilateral well composed of 4 legs. This was carried out despite the absence of proven ways to stimulate each lateral individually. This intervention would also present the following challenges: Well displacement and stimulation would require multiple re-entries into each lateral, all conducted from a drilling rig. All the laterals were known to branch off from the low side of the bore, so individual lateral and main-bore selection would be complex. Extended reach laterals require accurate friction lockup modelling and mitigations. The unique solution presented in this paper includes the use of real-time Hybrid cable coiled tubing (RTHCT) technology. This incorporates a hybrid cable installed in the coiled tubing (CT) string and a modular sensing bottom-hole assembly (MSBHA). Electrically controlled indexing tool, inclination sensor, tool-face sensor, and hydraulic knuckle joint were used as part of the BHA to enable real-time diagnostics and dynamic controls from surface to successfully enter the lateral legs. The MSBHA enabled the orientation of the BHA electrically to any position required using software to determine and control the exact position of the BHA. This paper presents a solution to all the above-mentioned challenges. It discusses the successful implementation of the RTHCT to displace and stimulate all the 4 laterals in a single CT trip in less than seven days, pumping over 7,000 bbls of various chemical systems and covering an open-hole length of 11,176 ft. Unlike other technologies, the RTHCT technology confirmed entries into the laterals without the need to tag the bottom of the lateral, saving substantial time. Enabling re-entry in these 4 laterals represented a world record translating into major efficiency improvements and cost savings for the project. This intervention also represented the first time in Kuwait that more than 2 laterals have been accessed in a CT run.

Measuring and Analyzing the Magnetic Content of Drilling Fluid

Magnetic contamination of drilling fluid can impact the accuracy of a directional survey by shielding the magnetic field. Additionally, this contamination, such as swarf or finer magnetic particles, can agglomerate on the downhole tool or BOP and cause tool failure in the worst-case scenario. Thus, it is necessary to measure the magnetic content of drilling fluid. However, there is no recommended practice in API or ISO for this purpose. A simple experimental setup and measurement system was developed that can be easily deployed in the rig site to measure the magnetic contamination of drilling fluid. 47 drilling fluid samples were collected from a multilateral production well drilled with a semi-submersible drilling rig located in one of the North Sea's fields. The magnetic content of these samples was measured using the established method, and the microstructure of the collected content was analyzed using a scanning electron microscope (SEM) and x-ray diffraction analysis (XRD). Ditch magnets are commonly installed in the flowline on the rig to remove the swarf and finer magnetic particles, if the design is optimized. Ditch magnet measurement data of the well that the drilling fluid samples were collected from is presented. Operational details and common factors that might increase the production of the magnetic content were also investigated. By comparing the measured magnetic contamination of the drilling fluid samples and ditch magnet measurement data, it was possible to evaluate the efficiency of the ditch magnet system.

First Ever Gas Simops Implementation In Abu Dhabi Offshore: A Success Story

Gas SIMOPS is a concurrent execution of two or more activities at same time, i.e., Drilling Operation, Oil Production & Gas Injection on an offshore wellhead tower thereby ensuring uninterrupted oil production and continuous reservoir pressure management from gas injection. The alternative to gas injection in this scenario was gas flaring, which has major environmental and financial impact. Considering continuous presence of personnel on drilling rig working over wellhead tower with high pressure gas injection; extensive Risk Analysis were conducted, and additional control/Mitigation measures were implemented. This initiative also contributed to the zero Gas flaring vision of the company by achieving a huge quantity of CO2 emission reduction. This successful Gas SIMOPS model is already being extended to other fields. To achieve this objective and keeping with 100% HSE, an in-house multi-disciplinary team collaborated and successfully executed Gas SIMOPS for the first time in UAE Offshore. Execution of Gas SIMOPS has brought major economic benefits to the company with additional Gas savings incurred.

Understanding the Impact of Monsoon Season in Malaysia Water Based on Data Analytics for Planning and Executing Drilling Operation

Drilling operation in Malaysia are typically from offshore, thus offshore weather condition does contributed to the success or delay of a drilling operation. Wait on Weather (WOW) especially during monsoon season in Malaysia has impacted Operator's drilling operation, thus incurring additional cost to Operator. Monsoon season in Malaysia is typically from November to February every year. This paper will discuss and share the statistics of actual WOW happening from 2008 to 2019 in Malaysia water especially for jack-up rig (JUR) and tender assisted drilling rig (TADR) which are two common rigs in Malaysia water. The data was collected from one of the drilling operator in Malaysia. These data will be of assistance to Operator in better planning and executing drilling operation with the actual statistics as the risk factor. WOW is considered as non-productive time (NPT), thus NPT data gathering from Operators in Malaysia water were conducted. Data was then filtered to achieve the WOW data. WOW data was segregated between region in Malaysia which are Peninsular Malaysia (PM), Sabah (SB) and Sarawak (SK) as well as rig type, which are JUR and TADR. Distribution analysis were made to calculate the average and observe the maximum numbers of actual WOW occurrence. Further analysis was made to zoom into monsoon season in Malaysia which typically in November to February. 11 years data is generally good coverage for the analysis since it covers the up and down of oil and gas industry. Analysis was also done for both mob/demob and operation stage where it can be observed that WOW for mob/demob stage during monsoon season is significantly higher compared to operation stage. At the end of the analysis, the average or maximum numbers of WOW will be shared, and it will be used as recommendation for future projects to consider these figures as WOW risk factor and embed in the planning stage. This paper will help not only Operators in Malaysia water but the host authority on understanding the WOW risk factor during monsoon season. As WOW is not something that can be predicted, utilizing the standard results from actual statistic data for the past 11 years will assist engineers to incorporate the WOW risk factor during planning and execution stage. Rig and project sequencing can be optimized with understanding of WOW impact thus reducing the value leakage during operation due to WOW.