Advanced Laser-Photoionization Scheme of Separation of Heavy Isotopes in the Gases Separator Devices

An effective approach to determining the parameters of the optimal schemes of the method of laser selective photoionization of atoms (elements and isotopes) with finite ionization due to collisions, ionization by a pulsed electric field, ionization through high (Rydberg) states and narrow autoionization resonances for the separation of heavy isotopes has been proposed. in gas separator devices. On the basis of the theory of optimal control and previously developed quantum models for calculating the characteristics of elementary atomic processes, optimization models of isotope separation are numerically implemented in the scheme of selective laser photoionization with ionization due to collisions in gas mixtures, ionization by a pulsed electric field, autoionization, etc. etc. The data obtained quantitatively confirm the promise of the method of laser photoionization with finite ionization due to collisions, ionization by a pulsed electric field, ionization through high-lying (Rydberg) states and narrow autoionization resonances and give a set of parameters for the desired optimal schemes, in particular, the laser pulse optimal shape for rubidium and uranium isotopes.

Unlocking ESP Potential in High Gas/Liquid Ratio Wells Using Gas Lock Prevention Control in West Java Field, Indonesia

West Java field operated 60 electric submersible pumps (ESPs) as a lifting method with 2.850 BOPD production contribution. These ESP wells produce from a mature structure. At one point, 48% of ESP operation were shut down due to ESP non-optimum operation. The challenges in ESP operations in the asset are high gas-liquid ratio (GLR), impurities, sand and scale buildup, and well integrity where high GLR was deemed as the major problem that deteriorated the ESP's performance. Conventional ESPs gas separator were installed in the field, but the gas-handling device could not handle more than 45% free gas while some wells have more than 50% free gas. Three wells in particular were assessed, Well A, Well B, and Well C, which have 585, 1196, and 1690 average GLR respectively. These wells had problem with reduced pump efficiency and very low run life due to frequent ESP trips which were caused by the gas lock problem. A solution to maintaining oil production was by changing the production zone to zone that producing less gas and by installing more advanced gas-handling device. However, the probability of experiencing high gas production from new zones can't be ruled out therefore other mitigation plan had to be found. Gas lock protection control is an algorithm that manipulates ESP real-time rotational speed to prevent gas interference inside pump. The algorithm was introduced as a mitigation measure and commissioned in July 2020 at Well A where it directly optimized production by 16%. To prove the robustness of the gas lock prevention control, the project was then extended to Well B and Well C which began to implement gas lock prevention control in August 2020 to handle the increase of their gas production. Thanks to this gas lock prevention control, the wells have been able to maintain production without spending either time or money to change production zone or to change the ESP completion. Going forward, gas lock protection control will be set as an option on ESP devices. Thus, unplanned gas interference effects may be reduced in other wells that being produced by ESP thereby helping to maintain production at an optimum level.

An Overview of Surmont SAGD ESP Gas Handling Project to Mitigate Production Effects of NCG Co-Injection

NCG (Non-Condensable Gas) co-injection with steam has been in operation at Surmont SAGD field since 2017. After a significant number of operational attempts to mitigate ESP no flow events (deadheading) suspected to be instigated by increased production of gas (typical SAGD GOR 5-10 m3/m3) a strategy was developed to focus on completion adjustments to the ESP on candidate SAGD producers. These changes were completed in late 2019 to help reduce the loss of production, which could impact viability of NCG co-injection at Surmont. Three separate completion adjustments were made: an inverted shroud installation, a larger OD pump with a gas separator, and lowering of an ESP to the lowest possible TVD. A comparison of the production and operational performance before and after each completion adjustment was completed. In-depth design reviews between CPC and the equipment vendor were done to ensure maximum chance of positive benefit. The inverted shroud installation was expected to improve gas separation efficiency, leading to a reduction in the frequency of No Flow Events (NFEs), which were impacting production rates. The shrouded ESP performance on the first candidate well showed no NFEs with a significant increase in production rates compared to the baseline before the completion adjustment. The larger OD pump with gas separator install was also expected to reduce or completely prevent NFEs. the results were also positive, with an increase in production and no further NFEs recorded. Lowering of a third ESP to a point as close as possible to the liner hanger did not achieve any long-term change in production performance. With the success of the inverted shroud, a second installation was completed on the third well where the ESP was being lowered. A production increase and prevention of NFEs were documented like the first shroud installation, confirming the benefit of the shrouded ESP design. The completion changes confirmed that suitable adjustments to mitigate the effects of NCG injection are possible, with further development on design required to optimize for production capacity and long-term performance. With the results seen so far, further installations will be completed in the future on appropriate candidates to continue to mitigate the effect on ESPs of produced NCG volumes.

Recent Enhancements for Coiled Tubing Descaling Treatments in Middle East

Successful coiled tubing (CT) descaling interventions require control of several key aspects, including fluid leakoff into the formation, proper surface solids handling, and controlled hydrogen sulfide (H2S) release at the surface. Successful treatment control is achieved by monitoring the surface and downhole parameters. The recently introduced pressure and fluid management system, crosslinked foam-based fluid, and a fluid mixing system for CT descaling treatments pose challenges that require enhancements to these elements for successful treatment. The pressure and fluid management system was enhanced to include a new high-rate mud/gas separator to 1) increase gas/fluid separation capacity and avoid foam flowing to flare, 2) rig up the flare line with inclination to allow all water to be drained and prevent formation gas flowing to flare lines, and 3) increase retention time for better foam breaking and material settling. A liquid flowmeter was also added to improve influx and leakoff control by monitoring the volume of liquid injected and matching the volume of liquid returned on surface in addition to the level gauges on the return tanks of the pressure and fluid management system. The foamed-based fluid breaking system and H2S presence in returns were mitigated by removing crosslinker and introducing an H2S scavenger on returns whereas foam breaking was enhanced by additional breaker injection points on returns. Fluid mixing capabilities were enhanced by the introduction of an on-the-fly continuous mixing system that sped up and simplified the mixing process. The mud/gas separator efficiently separated the gas from liquid, leading the gas to be burnt at flare and the liquid to be processed in the pressure and fluid management system. It further helped in preventing the liquid flowing to flare, which lessened the risk of flare shutdown and H2S ventilation. The on-the-fly continuous mixing system provided a faster and more-efficient mixing process as an alternate to batch mixing. These system-controlled metering, mixing, and monitoring capabilities significantly reduced the crew and equipment footprint, leading to minimizing the health, safety, and environment (HSE) concerns and cost savings. The fluid flowmeter allowed efficient choke and bottom-hole pressure control. Fluid flowmeter readings helped in choke and bottom-hole pressure reading adjustments based on amount of fluids pumped and matching the same amount of fluids returned at the surface. It prevented the fluid leakoff into the formation or influx of gas into the wellbore. Additionally, this new process created better control of downhole differential pressure during the scale cleanup and transportation. This project integrated different technologies and techniques that can be utilized for descaling treatment enhancements. The recent enhancements to the CT descaling operation resulted in greater efficiency, cost savings, reduced formation damage, and safe operations.

Introducing the Application of Hybrid Gas and Sand Control in Sucker Rod Pump (SRP) Case Study Old Rimau Mature Field South Sumatera

Objective/Scope: Challenges of sucker rod pumping operation in high gas and solid production;The implementation of integrated down-hole gas and solid separation in one device. Method procedure/processes: Old Rimau Fields in South Sumatera produce oil from sandstone reservoir with GOR above 800 scf/stb and solid production resulted from fracturing proppant flow back. Due to these conditions, some problems such as gas lock or interference, pump leakage, and rod parted were discovered which resulting in low SRP run life. The installation of sand screen and gas anchor has been implemented to encounter this issue. However, this initiative still ineffective due to limited conditions. If the sand screen was installed to control the sand, then the gas anchor to control the gas could not be installed and vice versa.Results, observations, conclusions: Integrated solid and gas handling called "hybrid" device has been introduced. The device is connected directly at the bottom of down-hole pump consist of three section, the upper section for intake and gas separator, the middle section for gas and solid separator, and lower one for solid container. The first utilization was conducted in three SRP wells, which are KG-09, LKP-21, and KG-10. Previously, these wells were shut-in due to down-hole problem. After installing the device while well service, the SRP run normally to produce the oil. The increasing of pump load performance was also obtained, indicated by the dyna card. At this time, the SRP is still running and run life is still under surveillance. This paper will explain the new technology end-to-end implementation of the integrated down-hole sand and gas control in one device for Sucker Rod Pump (SRP) system.

Numerical Modelling of Two-Phase Flow in a Gas Separator Using the Eulerian–Lagrangian Flow Model

Gravity-driven separators are broadly used in various engineering applications to remove particulate matters from gaseous fluids to meet legislation demands. This study represents a detailed numerical investigation of a two-phase cyclone separator using the Eulerian–Lagrangian gas flow method. The turbulence is modelled using the Reynolds stress model (RSM). The technique has successfully predicted the typical trends and variations seen in such gas separators with an average error of approximately 5.5%. Also, the computed results show a realistic agreement with the experimental measurements.

Gain scheduling control applied to oil and gas separator level loop

Modeling and simulation applied to level control of oil and gas separators in production facilities is a very important tool because makes possible to perform tests that probably could not be viable due to operation and safety constraints. Asides the level dynamics can be well understood regarding the physical model, there will always be non-linearities to approach using a system identification procedure, requiring reasonable care on linear model identification. In order to assure a desired control performance, an adaptive control strategy has been proposed for level control for an oil and gas separator using the gain scheduling technique. Based on a first order process without time delay, the static gain and time period were determined for each point inside the operational space range of the equipment and by Internal Model Control (IMC), the tuning matrix found and converted into a function of operational parameters using polynomial interpolation methodology for future application in a real commercial PI controller. The horizontal separator was simulated using MATLAB/SIMULINK® and data from a real separator vessel were used to identify and validate the proposed process modeling in attempt to test an adaptive control strategy for practical applications. Once the GSC was implemented, simulations were performed over the non-linear system and results have shown better performance indexes for GSC while compared to the conventional PI controller for both servo and regulatory problems with reductions up to 17.65% for IAE, 29.88% for ISE, 16.38% for ITAE, 29.00% for ITSE and 13.20% for Control Effort (CE).