Production Optimization Challenges and Solutions for Heavy Oil - North Kuwait

Because of the high cost associated with tubing replacement, rodwear tubing leaks are one of the most costly types of subsurface failures on sucker rod pumped wells. However, many rodwear tubing 1eaks can be prevented by properly identifying the cause of tubing leaks and taking the appropriate corrective measures. While severe hole deviation is most often blamed for rodwear tubing leaks, case studies show that most rodwear leaks are caused by accelerated corrosion which is the result of the removal of a protective corrosion scale from the inside of the tubing. For this reason, the key to economically eliminating rodwear tubing leaks is correctly identifying the problem as either mechanical wear or corrosion wear and then implementing the appropriate corrective measures. Four case histories, involving a total of nearly 100 problem wells, are presented to illustrate the methods used to differentiate between corrosion-wear and mechanical wear. In these fields, tubing leaks were reduced by as much as 80% by properly identifying the cause of the leaks. Introduction Approximately 100 wells in five (5) different fields were investigated to determine the cause of their excessive downhole wear. Many of the subject wells were experiencing tubing leaks as often as once every six months. Without exception, every problem well had been labeled as a "crooked hole". Upon further investigation, it was found that only one well out of the group had a problem that could be attributed solely to a crooked hole. That well had a 25° average deviation from vertical and still had a projected life without tubing leaks of three years. From this investigation, it was determined that other factors, most importantly corrosion, have a much greater effect on downhole tubing wear than well deviation. Even mild corrosion, when combined with wear can result in a tubing life as short as two months. For this reason, it is important that corrosion-wear leaks be identified and treated as such. Mechanical Wear Mechanical wear is the removal of metal due to the frictional rubbing of the sucker rod string upon the tubing. The softer of the two metals should suffer the most weight loss. With nearly every combination of tubing and couplings, the tubing is the softer metal. (Table 1) However, from the field studies, it can be shown that on wells with J-55 grade tubing, T-grade sucker rod couplings, and a mechanical wear problem, the sucker rod coupling will usually fail first. This can be attributed to the fact that the tubing is wearing over the full length of the stroke where the sucker rod coupling is only wearing over its short 4-inch length. An effective method for reducing downhole mechanical wear is the use of soft rod guides to prevent the rod coupling from contacting the tubing wall. Rod rotators can also extend the life of rod guides and rod boxes by distributing the box or guide wear more evenly.

Abstract: In the oil and gas sector, supervisory control and data acquisition (SCADA) systems have become a revolutionary force that are transforming operations throughout the whole value chain. This in-depth analysis looks at the development, design, and various uses of SCADA systems in the upstream, middle, and downstream domains. It projects that the global SCADA market for oil and gas will grow to $4.52 billion by 2026. Real-time well monitoring, production optimization, and remote operations are made possible by SCADA systems in upstream operations, which greatly increase output and efficiency. The goal of midstream applications is to increase pipeline efficiency and safety by using predictive maintenance, enhanced leak detection, and flow optimization. By streamlining quality assurance, energy management, and process control, SCADA systems can completely transform refinery operations. SCADA deployments are not without difficulties, though, including data management complications, cybersecurity threats, and legacy system interoperability. In addition to addressing these problems, the study looks at new developments that could improve SCADA capabilities, such as edge computing, digital twins, AI and machine learning integration, and 5G technology. According to the research, SCADA is essential for promoting efficiency, safety, and innovation in the oil and gas industry. Businesses that successfully integrate SCADA technologies while overcoming implementation obstacles will be best positioned to prosper in the complicated and fiercely competitive energy market.

In view of the insufficient informationization of the stainless steel pipe production line., such as the inability to collect the machine tool's processing data in real time, the inaccurate production information feedback, and the insufficient monitoring of the equipment status, a SCADA (Supervisory Control And Data Acquisition) system is designed to effectively control and monitor the entire stainless steel pipe production line to achieve the information construction of the factory. Siemens S7-1500 series PLC is used as the lower computer of this system, and communicates with the upper computer software through Siemens S7 protocol. The SCADA system is developed in C# language, and its functions include equipment status monitoring, production process monitoring, production statistical analysis and electronic board display. The SCADA system can realize the automation of data collection, data processing and data analysis, which improves the production efficiency and management level of the production line.

Introduction Economical heavy oil production is possible by allowing formation sand to be produced along with fluid. Cold production has potential to increase subsequent enhanced oil recovery (EOR) efficiency, operating new technological possibilities for continuedeconomical oil production from these reservoirs. Heavy oil (10–15 ºAPI) in cohesionless sandstones (>30% porosity) can be exploited by permitting sand to enter the wellhole along with fluids. Information from Lloydminster and North Primrose areas is given in Table 1. To achieve sustained production, sand production must be encouraged through use of closely spaced high-energy perforations and through application or work over strategies that re-initiate sand production if it has stopped. Sand exclusion is disastrous; free sand flow is vital production mechanism, as yet incompletely understood(1). Blocking it by gravel packs or screens simply reduces the oil now below economical levels. Lowering Cold Production Costs To compete with offshore oil and absorb price differences between heavy and conventional oil production cost minimization is vital for the shallow (300 – 800 m) heavy oil reservoirs typical of Alberta and Saskatchewan Cretaceous deposit. Drilling costs can be lowered by using coiled tubing and smaller diameter drill hole; there is little evidence that a larger hole is better for cold production. Workover costs can be lowered by using better pumps that do not sand in, and by better workover methods to reduce service TABLE 1: Enhancement of oil rate through cold production. Table Available In Full Paper. rig time and re-establish sand production. Economic and environmentally acceptable sand disposal methods must be implemented(2). Finally, initial development must be planned with EOR production in mind to minimize additional redevelopment costs. Cold Production Mechanisms In these wells, conventional well theory predicts production rates of 0–2 m3/day, rather than the 5– 15 m3/day commonly obtained. Why does heavy oil flow more efficiently if 1–3% sand enters the wellbore with the fluids? A complete answer remains elusive, but the four major factors are likely enhanced drainage radius, grain movement, gas bubble expansion and continuous pore deblocking. Quantitative analyses have been developed for the first two(3, 4), and partly for the third mechanism(5). The fourth remains a qualitative concept. Enhanced drainage arises because thousands of cubic metres of reservoir are affected by large-scale sand production. Discrete cavities may exist, piping tubes may develop, and zones dilated from 30% to 36–40% porosity may all accompany massive sand production. Each of these will increase well flow capacity. Closed-form solutions for piping tube or general yield models show that a factor of 3 to 4 in sustained rate productivity can be expected (3). However, improvement factors of 4 to 10 and more are common in cold production. Grain mobility facilitates liquid movement, independent of permeability enhancement effects. A theoretical model of local fluid rate enhancement in mobile grain systems shows that increased flow rates up to a factor of two can be expected because of the reduction of drag forces(4). There is a variant of the gas bubble theory which may help explain improved production(5).

In rod pump applications around the world heavy oil and sand production is believed to be a dangerous combination. This paper highlights a case study of a heavy oil well in the North Kuwait field where sand production was monitored closely to avoid flow line choke and down hole failures. This case study was used as a pilot for the neighboring wells producing from the same reservoir. In case of wells producing heavy oil with considerable sand production and that undergo cyclic steam stimulation the challenge is often at the end of the production cycle. While the oil is thin and has good viscosity the sand settles itself at the bottom. However, with time as the oil gets colder and thereby heavier, it carries the sand along with it to the surface causing plug in the flow line. This is due to the high viscosity of the oil. This is believed to be the end of production period beyond which it would have been impossible to produce any further even after sand cleanup. Certain operational procedures were established to ensure the integrity of the down-hole equipment and to avoid the failures. It has been observed that by effective sand monitoring it was possible to determine the next injection cycle with more precision. This standardized the injection and production cycle. The flow line choke up problems were completely eliminated as the production period would cease as soon as some sand would begin to appear at the surface. It was possible to establish API gravity cutoff for oil production thus avoiding rod and pump failures. This implementation has been undertaken for the entire field and has shown significant operational efficiency. A pilot was conducted to justify the use of sand production as an indication for the next production cycle for heavy oil well under cyclic steam stimulation.

The number of real-time supervisory control and data acquisition (SCADA) measurements in power distribution systems is scarce. This limits the reliability of state estimation (SE) results for distribution systems. Therefore, some studies seek to enhance the observability and SE accuracy of distribution systems by incorporating advanced metering infrastructure (AMI) data with the SCADA measurements. However, the hourly updated AMI data may be too coarse to capture system changes, especially in the presence of intermittent renewable energy sources. This issue is addressed by proposing a hybrid SE framework integrating a data-driven estimator and a model-based estimator. To be specific, the data-driven estimator combined with a topology identification method is presented to solve the DSSE problem between AMI scans, and the model-based estimator is employed to ensure robust estimation results against gross errors at a lower time scale. The proposed hybrid SE switches from the data-driven estimator to the model-based estimator once the AMI data is updated. Such a solution allows for capturing system changes at different time scales and improving the real-time and reliability of distribution system state estimation. Simulations are conducted on a sample distribution system to illustrate the characteristics of the proposed hybrid SE.

Cold production as a new primary production process can be used successfully in heavy oil unconsolidated sandstones. Ideal reservoirs are 5–15 m thick uncemented sands with high saturations of <20°API oils with gas in solution without free water or gas zones. However, application of Cold Production to many other cases in other parts of the world imust be investigated. Strategies to initiate sand production involve aggresive perforation and swabbing measures. Keeping sand production stable after initiation requires pumps to cope with large initial sand ratios in a foamy oil form for several weeks, and smaller amounts of sand and foamy fluid continuously for many months. Restoring stable sand production after blockage is currently an "art", and various workover methods are used: better controlled work-over approaches and new technologies are needed. Sand and "gorp" separation from oil at surface is necessary, economic and environmentally sound disposal of these materials probably involves re-injection into depleted reservoirs.

The convergence of Supervisory Control and Data Acquisition (SCADA) systems with the Internet of Things (IoT) and Machine Learning (ML) is redefining automation, security, and operational efficiency across industries. Traditional SCADA systems, widely used in critical infrastructure such as energy, water management, and industrial processes, are undergoing a transformative shift with the integration of IoT. IoT-enabled sensors and devices provide real-time data streams from diverse operational environments, enabling SCADA systems to achieve enhanced situational awareness and remote monitoring capabilities. Machine Learning further augments SCADA systems by introducing advanced analytics for predictive maintenance and anomaly detection. ML algorithms analyse vast datasets collected through IoT devices to forecast system failures, optimize resource utilization, and ensure uninterrupted operations. This predictive approach minimizes downtime, reduces maintenance costs, and improves overall efficiency. Cloud-driven security frameworks are pivotal in addressing the growing cybersecurity challenges associated with SCADA and IoT integration. These frameworks provide scalable and resilient solutions for protecting data integrity, preventing unauthorized access, and mitigating cyber threats. The deployment of ML-driven cybersecurity solutions enhances the ability to detect and respond to sophisticated attacks targeting SCADA environments. This paper examines the evolution of SCADA systems in the era of IoT, focusing on the transformative role of ML and cloud-driven security. It explores innovative applications, highlights the challenges of integrating these technologies, and provides insights into future advancements for creating robust and secure automated systems.

The key objective of the project is to process the real time data acquisition wirelessly using SCADA system. In large industries several processes are carried on concurrently, so there is a necessity to observe all the processes and govern the factors affecting the process. By using a technology like Wireless SCADA (Supervisory Control and Data Acquisition) we can meet the goal successfully. To manifest this real-time situation, a temperature recording system for a remote plant set-up is developed by Visual Studio. Temperature sensors are interfaced to the AT89S52 microcontroller. Information collected from the sensors is continuously sent over 2.4GHz trans-receiver wirelessly to the microcontroller which is then received at the corresponding 2.4 GHz USB type trans-receiver connected to a PC / Laptop. In the computer “DAQ System” (software) is loaded which takes the collected data and presents them on PC / Laptop’s front panel, and also logs them into the database. We can customize parameters like set point, lower limit and higher limit on the SCADA screen. As the temperature of a sensor goes below set point the microcontroller issues command to the respective relay. The field devices interfaced through relay contacts (with respect to their sensors) are turned OFF (or ON in vice versa). Higher limit and lower limit features are present for producing an alarm on the PC in the event of breakdown of system. Therefore, processes at dangerous places can be controlled with good accuracy and enhanced safety using SCADA.

SCADA (Supervisory Control and Data Acquisition) is one of the systems used to monitor and control ESP (Electric Submersible Pump) offshore in real time. SCADA system consists of three main parts, namely MTU (Master Terminal Unit), RTU (Remote Terminal Unit) and communication media (link). MTU or Master, functions as a communication controller by sending commands (queries) while RTU or Slave, functions to respond to the Master's command about the condition of the plant. Communication between Master and Slave uses Modbus protocol communication rules. Background of the problems faced by monitoring and control system for ESP wells offshore is the unstable quality of SCADA system communication network (intermittent), multiple delays causing data from ESP well is not fully stored in the database. In current condition, communication media on ESP controller uses serial RS-485 while in the implementation of SCADA system using Ethernet communication media. Purpose of this research is to analyze the improvement of communication network reliability by comparing technology and empirical testing on SCADA system. Results of this research have an impact on production optimization, reduction of operational and equipment maintenance costs and allow for the development offuture technologies such as the Internet of Things (IoT).

This paper presents an implementation of automation scheme for control of three phase Permanent Magnet Synchronous Motor (PMSM) drive. Performance evaluation and monitoring of drive is described using Supervisory Control and Data Acquisition (SCADA) and Programmable Logic Controller (PLC) system. The control, operation and monitoring of PMSM drive in three basic modes, i.e. position, speed and torque modes is achieved through PLC programming and SCADA. A Human Machine Interface (HMI) control is also developed for operation of drive system at field level controls. Ladder logic programs according to desired control mode of operations are developed to control and monitor the status of PMSM drive. SCADA screens have been developed to control and monitor the status of the motor and for field level control HMI touch screens are designed. The real time data related to PMSM drive such as output of position encoder, torque developed by motor, power input to motor, speed etc. are accessed for supervisory control of drive.

The advent of microgrids and increased utilization of renewable energy sources (RESs) contributed to the uncertainty of power generation in hybrid power systems (HPSs), which necessitated stringent monitoring and control of grid conditions. The large power swings in RESs cause significant deviations in frequency that can disrupt the stability of the system in case timely control actions are not initiated. Therefore, frequency control is of prime importance and has been handled by different levels of controllers in power systems. Data acquisition plays a major role in frequency control of HPSs for performing real-time control. In this context, supervisory control and data acquisition (SCADA) systems and phasor measurement units (PMUs) are studied based on their dynamic performance in real-time data acquisition. Additionally, the role of PMUs in frequency stability has been reviewed and the challenges faced in enabling PMUs for frequency control of HPSs has been presented.

ABSTRACT: Hydrothermal sandstone is an important form of geothermal energy, which is usually distributed in areas with shallow formation water and obvious geothermal activities, and has great potential for exploitation. However, the exploitation of hydrothermal sandstone reservoirs is often accompanied by severe sand production, which reduces the heat exchange efficiency and the service life of the devices. This paper presents the prediction method of sand production in hydrothermal sandstone reservoirs. Firstly, we conducted mechanical tests on hydrothermal sandstone cores. Secondly, the criteria for judging hydrothermal reservoir stability were proposed and the wellbore-reservoir coupling model was established. Finally, the influence of different reservoir and perforation parameters on sand production was analyzed. The results show that: 1) the interface between the borehole wall and perforation is the weakest place in the well, and the risk of sand production is the maximum; 2) the reservoir parameters (cohesion, friction angle, Poisson's ratio) and perforation parameters (phase angle, length, diameter, density) affect sand production; 3) the perforation phase angle of 60° is the best for sand control. This paper provides valuable insights and guidance for sand production and sand control in the development of sandstone geothermal reservoirs. 1. INTRODUCTION Geothermal energy is a renewable resource obtained from the Earth's internal heat (Fridleifsson, 2001). Hydrothermal sandstone, primarily consisting of sandstone and carbonate rock, constitutes a significant geothermal reservoir, containing enormous amounts of energy (Gallup, 2009; Zhang et al., 2019). However, the high sand content presents a considerable challenge during reservoir exploitation, causing adverse impacts on exploitation efficiency, equipment longevity, and production safety (Ahad et al., 2020; Song et al., 2021). Managing sand production is critical for successful geothermal resource development, making reliable prediction studies essential (Sun et al., 2023). At present, research on sand production prediction mainly focuses on laboratory experimental and numerical simulation. Through research, it has been observed that reservoir parameters (Shahsavari et al., 2021) and perforation parameters (Shabdirova et al., 2019) significantly impact sand production. Nouri (Nouri et al., 2006) investigated the influence of perforation and reservoir conditions on sand production, proposing specific criteria to ascertain sand production occurrence and extent. Bai (Bai et al., 2011) introduced equivalent plastic strain to enhance the accuracy of sand production prediction. Some scholars have developed erosion models or employed techniques such as ALE and FEM to account for rock erosion effects in sand production issues (Gravanis et al., 2015; Li et al., 2018). Zamani (Zamani&Knez, 2021) introduced a novel Safety Factor Index specifically designed to assess the influence of mechanical stresses and hydrodynamic forces on sand production in sandstone reservoirs. Khamitov (Khamitov et al., 2022) employed a CFD-DEM coupled model to examine the sand production mechanisms in the perforation zone. These studies have provided crucial references and theoretical foundations for dealing with sand production prediction issues in sandstone reservoir exploitation.

In the majority of public utilities, achieving optimum utilisation of existing capital assets for meeting future predicted demand is a major function at all levels of management. In this paper, a set of maintenance strategies and a computerised Supervisory Control and Data Acquisition (SCADA) system for achieving an integrated maintenance management is described. The objective of the integrated system is to enable maintenance projects to be better controlled and resources to be properly utilised. A case study is used to illustrate the proposed maintenance strategies which include the identification of real time and historical data required to measure, visualise and quantify the progress of maintenance activities. Existing and proposed systems and procedures are analysed and discussed with major recommendations included for the design and implementation of this integrated system.

Challenging aspects to heavy oil field development are the large volume of data which is collected, in particular from cored evaluation wells, and the difficulty in evaluating of the quality of such data. This paper outlines an approach to summarize coring data and procedures from two heavy oil fields in North Kuwait, and then to compare those summaries with similar heavy oil operations in other countries, in order assess their quality and degree of representativeness. For two North Kuwait heavy oil fields, data was tabulated for the cumulative amounts of core cut and recovered relative to their field areas. This data was then further analyzed to summarize recovery by rock type, and assess the quality and quantity of plug samples collected. Benchmarks were established by summarizing core data from similar heavy oil operations in other countries, and the North Kuwait heavy oil data was then compared with those benchmarks. In a similar manner, documented core handling procedures for North Kuwait Heavy Oil operations were compared with procedures from similar heavy oil operations in other countries. The benchmarks which were used to compare North Kuwait Heavy Oil data summaries with other countries include the following: 1) Coring Well Area Coverage Densities; 2) Coring Well Vertical Coverage of Cap Rock and Reservoir Intervals; 3) Core Plug Sample Rate and Survival Rate; and 4) Core Handling Procedures and Volume of Coring. For many of the benchmarks used, North Kuwait heavy oil operations compare favorably with similar operations from other countries. However areas of improvement were identified from these benchmarks in terms of areal core coverage, vertical core coverage, core plug rates and core handling procedures. It is expected that these improvements, when implemented, will lead to a more representative sampling of the areas and rock types (reservoir rocks, baffles and cap rocks) in North Kuwait. This in turn should lead to a better understanding of fluid volumetrics, reservoir characterization and subsequent life of field development. As well by applying a focused approach to future coring operations, a significant cost savings is expected relative to original evaluation well plans. A significant product from this study is a large summary database of all coring information for two North Kuwait heavy oil fields, which can be queried by area, rock type and sample type. This data base has been compared with similar operations in other countries using a series of benchmarks. Planned future coring and sampling operations have been modified through the use of this benchmarking tool.