Assessing simultaneous-separate production in a multilayer reservoir

First posted January 12, 2016 For additional information, contact: Director, Western Fisheries Research CenterU.S. Geological Survey6505 NE 65th StreetSeattle, Washington 98115http://wfrc.usgs.gov/ The biological and hydraulic performance of a new portable floating fish collector (PFFC) located in a cul-de-sac within the forebay of Cougar Dam, Oregon, was evaluated during 2014. The purpose of the PFFC was to explore surface collection as a means to capture juvenile salmonids at one or more sites using a small, cost-effective, pilot-scale device. The PFFC used internal pumps to draw attraction flow over an inclined plane about 3 meters (m) deep, through a flume at a design velocity of as much as 6 feet per second (ft/s), and to empty a small amount of water and any entrained fish into a collection box. Performance of the PFFC was evaluated at 64 cubic feet per second (ft3/s) (Low) and 109 ft3/s (High) inflow rates alternated using a randomized-block schedule from May 27 to December 16, 2014. The evaluation of the biological performance was based on trap catch; behaviors, locations, and collection of juvenile Chinook salmon (Oncorhynchus tshawytscha) tagged with acoustic transmitters plus passive integrated transponder (PIT) tags; collection of juvenile Chinook salmon implanted with only PIT tags; and untagged fish monitored near and within the PFFC using acoustic cameras. The evaluation of hydraulic performance was based on measurements of water velocity and direction of flow in the PFFC. The PFFC collected 156 juvenile Chinook salmon and 280 individuals of other species, primarily dace (Cyprinidae) and largemouth bass (Micropterus salmoides). The collection included one of the 212 acoustic+PIT-tagged fish detected near the PFFC and two of the 1,505 PIT-tagged fish released near the head of the reservoir. No juvenile salmonids were collected between early July and early September when water temperatures near the water surface were greater than about 16 degrees Celsius (°C). Depths of acoustic+PIT-tagged fish indicated a preferential selection of water temperature of 13–15 °C, which was often deeper than the entrance to the PFFC, and those fish rarely were at depths with water temperatures greater than 16 °C. Dam passage of acoustic+PIT-tagged fish was similar to previous years, but much of the passage occurred prior to the date the PFFC began operation. Discovery Efficiency, the proportion of acoustic+PIT-tagged fish detected in the cul-de-sac that were within 10 m of the PFFC entrance and 0–6 m deep (the Discovery Zone), was 0.736 during the Low treatment and 0.639 during the High treatment. Entrance Efficiency, the proportion of fish in the Discovery Zone that were collected by the PFFC, was 0.007 during the Low treatment and 0.000 during the High treatment. Fish Collection Efficiency, the proportion of acoustic+PIT-tagged fish collected of those detected in the cul-de-sac, was 0.005 and 0.000 during the Low and High treatments, respectively. The areas of highest use by acoustic+PIT-tagged fish were between the stern of the PFFC and the outlet of the reservoir (a water temperature control tower), with the greatest use being near the tower. Results from untagged fish detected with acoustic cameras indicated that most fish near and within the PFFC were in the 90–250-millimeter length bin and few were less than 60 millimeters long; most fish were present during crepuscular periods; trajectories of fish outside the PFFC were rarely directed toward the entrance; and many fish entering the PFFC swam back out before they could be collected. The hydraulic performance of the PFFC did not achieve the design goals of smooth acceleration of inflow culminating in a peak water velocity of 6 ft/s and, as a result, the hydraulic performance likely contributed to the low biological performance. The greatest water velocity measured in the PFFC (1.87 ft/s) was lower than designed due at least in part to the PFFC being lower in the water column than expected. Additionally, difficulties during anchor deployment prevented placement of the PFFC as near to the reservoir outlet as planned, resulting in a PFFC position outside the prevailing flow field and known areas of high fish densities. Overall, the results indicate that location, hydraulic conditions, water temperature, and shallow depth of the entrance were among the factors contributing to the low biological performance of the PFFC in 2014.

In recent years, the production of tight reservoirs with waterflooding in China has entered a progressively declining phase with unstable oil rate and higher water cut, rising challenges to any further enhancement of oil recovery. Targeting the high water cut and complex pore structure characteristics typical of these reservoirs, this work evaluates the reservoir compatibility of a microspheres-alternating-nanoemulsion flooding process and optimizes its injection strategy. Representative reservoir scenarios were first established; laser-particle-size analyzers and other laboratory instruments were then employed to quantify formulation-reservoir compatibility. A multiscale numerical study has been performed with CMG-STARS v.2022. The core-scale simulations systematically examined the influence of key factors on displacement efficiency improvement and water cut reduction, matched with the experimental results of core flooding tests. The combined experimental/numerical workflow furnishes a theoretical framework for optimizing the injection scheme. Beyond assessing formulation compatibility, the study delivers optimized injection parameters and strategies for microspheres-alternating-nanoemulsion flooding, providing both theoretical analysis and practical technology reference for improving oil recovery in tight reservoirs with higher water cut. Specifically, when the microsphere concentration increased from 0.1% to 0.3%, the minimum water cut was reduced by approximately 5%, while further concentration increases showed no significant additional impact on water content. Compared with water flooding, the relative permeability curve of the microspheres-alternating-nanoemulsion flooding system shifted entirely to the right. Numerical simulation of representative well groups revealed that a slug design with a microsphere-to-nanoemulsion ratio of 1:3 yielded the optimal enhanced oil recovery effect, and after ten years of production, the recovery factor increased by 0.46%.

We will discuss issues in developing a production-injection surface facility model to optimize both oil production and water injection strategy in a mature giant oil field. Surface facility modeling was done using commercially available software, which was coupled to Saudi Aramco's in-house reservoir simulator POWERS1. Multiple integrated strategies for analyzing production can be considered with such models. In this paper, we evaluate a facility optimization perspective where many wells are rerouted between multiple gas-oil separation plants (GOSPs) to maintain adequate reservoir pressure to deliver required oil production volumes at the lowest operating cost. We also consider cases where the objective is to evaluate injection allocation strategies, which honors surface constraints, especially surface flow lines’ maximum operating pressure restrictions. Results presented in this paper include a subsurface reservoir coupled surface facility model where proposed strategies are designed to reroute wells from five existing GOSPs producing at high water cuts to two remaining GOSPs for production consolidation. Such strategy allows for an immediate cost savings, since it reduces the number of plants while at the same time producing the required volumes of oil, at reduced water cut, while at the same time maintaining reservoir sweep and recovery since wells which otherwise might have been shut-in are kept on active production. Simultaneously with the option of optimizing oil production, rerouting offers the opportunity to examine water disposal strategies since water can be injected near locations where there might be either a need for additional sweep or simply for reservoir pressure control and redistribution without compromising overall oil production. We built a surface facility model consisting of five active GOSPs with a few hundred producers and injector (disposal) wells. The surface model is coupled to an over a million-cell reservoir model, containing a sub-set of all the wells available in the POWERS simulation model. Previous work had relied on describing exclusively the production system, leaving the injection system to be handled by POWERS’ well management rules and not subject to optimization or reconfiguration based on reservoir strategies. In this study, both the production and injection model have been constructed and calibrated using the latest available field data and history matched to field performance current at the time of calibration. Model calibration has been assisted by using automated scripts that transfer the relevant production and technical data from a corporate database to the individual model well files and which provide initial estimates for appropriate calibration parameter, such as productivity index, gradient curve matching or reservoir pressure at the time of a rate test, to current or historical field data. Those initial matches are later reviewed and validated on a well by well basis prior to use for prediction runs.

Experimental evaluation of thermal and hydraulic performance in multi-layer microchannel heat sinks with various flow configurations

Sewer system plays an essential task in urban cities by protecting public health and the environment. The operation, maintenance, and rehabilitation of this network have to be sustainable and scientifically. For this purpose, it is crucial to support operators, decision makers and municipalities with performance evaluation procedure that is based on operational factors. In this paper, serviceability and performance indicator (PI) principles are employed to propose methodology comprising two enhanced PI curves that can be used to evaluate the individual sewers depending on operational factors such as flowing velocity and wastewater level in the sewers. To test this methodology; a case study of al-Rusafa in Baghdad city is studied in which two combined trunk sewers are serving (Zeblin and ET-trunks). Hydraulic analysis for two scenarios (average and peak dry weather flows) is performed; afterward, performance evaluation showed a sub-index ranging from 0.5 (minimum level of performance) to one (excellent performance) which implicate that these two trunks, if well maintained will provide sufficient service to the catchment. By applying the serviceability and PI principles; a prioritizing tool is provided which help decision makers towards better management of the sewerage system.

Asri basin has been on producing since July 1989, currently there are 9 fields has been developed with strong water drive reservoir driving mechanism characteristic. Peak production was 196,000 bopd, presently producing 34,000 bopd with water cut of 99 %. Challenge faced in the studies had to deal with mature reservoir, declining production, depleted reservoir pressure, unrealistic recovery factor and the need to enhance asset value. Beyond that complexity, commercial challenge in rejuvenating the field becoming more critical due to falling oil prices. This paper present how integrated evaluation of mature offshore oil field performance and investigated various scenarios could add more value to the asset. Water flood, water shut off, and single field revitalization project has been implemented and it shows satisfaction result in reducing and maintaining production decline rate even increasing oil production volume. Recommendations also made to sustain and gain oil production by implementing successful projects to other field and also trying to implement Polymer Injection pilot project in Indonesia. The important thing in revitalizing a mature field is to define a customized asset evaluation approach to managed large amounts of data and identify the most important mechanisms in creating value-added solutions, while minimizing costs. The team captured this through innovative systems planning and operation, displacing the traditional lab-to-field R&D search in that multiple options were generated from within functional technology contributions. As expected, the results of full project implementation are satisfying. Depleted reservoir problem in major field producer has been solved by water flood project, the pilot project has been conduct in 1999 and shows great result in increasing oil production rate, within 2 years the oil production rate increase from 2,000 bopd to 12,000 bopd. Another project has been implemented in this major field is facies re-analysis, from this analysis new map are created, therefore new point of view can be extracted to support more comprehensive analysis, and the new analysis are very useful to gain oil production. Marginal field also part of the revitalization program in Asri Basin, in 2012 rejuvenation project has been conducted, and the result shows 4 times oil rate incremental, from 264 bopd to 908 bopd. One of other successful project is water shutoff, 2 wells are implemented for this project, and it can reduce water cut up to 17%, from 99% to 82% water cut. Those successful projects will be implemented for other field in Asri basin North Business Unit Area to Sustain and Gain Oil Production Rate.

<div class="htmlview paragraph">The antiwear results of a series of hydraulic fluids were determined using various bench wear tests including: Shell 4-Ball, Pin-on-V-Block Falex Wear Test, SRV Ball-on-Disk, Timken Block-on-Ring and a recently developed cyclic contact stress (3-vane-on-ring) test and the ASTM D-2882 Sperry-Vickers V-104 vane pump test. These bench tests were selected since they are used in the fluid power industry for fluid selection, qualification and performance troubleshooting. The results of this work showed that none of the bench tests evaluated provided any correlation with the wear rates obtained with the ASTM D-2882 pump test. Comparison of these results relative to fundamental lubrication principles and published literature on similar problems showed that bench wear test correlations are possible only if the conditions of the wear test, such as wear contact geometry, loading, speeds, and materials reasonably model the specific wear contact of interest in the hydraulic pump. Even then, the general reliability of the bench testing conditions should first be demonstrated by hydraulic pump testing.</div>

Evaluation of hydraulic fracture (HF) performances is critical to develop unconventional resources such as tight oil and gas. We present a probabilistic evaluation approach that integrates ensemble machine learning with Monte Carlo simulation. In the method, we employ the ensemble learning to develop a predictive model between well productivity and its influential factors including both geological properties and HF treatment parameters. Next, coupling the built prediction model with Monte Carlo simulation, an empirical cumulative probability distribution of the well productivity is generated. The well HF performance is assessed by estimating its cumulative probability value. The proposed method is applied to evaluate the HF performances in a developed block of the eastern Sulige region. The study shows that 19% of the wells were fractured with good quality and 55% of the wells were fractured with average quality, while the rest were stimulated with poor quality. The evaluations provide a guideline for optimization of HF designs of wells that have not been hydraulically stimulated in the region.

There are a large number of factors influencing the performance of hydraulic oils, and many of them can not be quantified. Currently, the evaluation indices of hydraulic oils are contamination, physical and chemical performance. In this paper, a new fuzzy comprehensive evaluation method is put forward, by which the oil can be synthetically evaluated from the aspects of physical and chemical indices, simulant indices and performance test indices.

Here we report the key success factors of the first polymer pilot at YPF in the south of Argentina and the consensus shifting strategy for polymer expansion in the current oil price context. We calculated water flow velocities in the reservoir using three multiscale history matched simulation models. We found that more than 80% of water velocities across the complete field are below1ft/day [normally assumed reservoir water velocity for calculating the resistance factor in laboratory experiments].We increased polymer concentration in 10 to 30% to ensure good mobility ratio in the high permeability streaks possibly located in the channel bars. This is very important because low end point water permeability (<0.09) could explain the success of water flooding in friable formation with viscous oil. This challenges the common assumption of poor performance because adverse mobility ration (> > 10). High permeability streaks (above 10 Darcy) are not characterised because they are often lost during coring or they are not suitable for coreflooding experiments. Instead, stochastic history matching supports the idea of greater water end point permeability (>0.2) in the high perm streaks. Then, the target resistance factor for polymer could be underestimated (underestimation of polymer concentration) and polymer injection might not perform as expected. Simulation-based analysis of flows in the pilot zone strongly suggests that one of the key success factors was pattern confinement. The pilot configuration is five-spot with 4 injectors, 1 confined producer and 9 offsets producer wells. After injecting 0.15 pore volumes of 2500/3000ppm polymer we recovered more than 11% ooip incremental oil above waterflooding from the central pattern and more than 6% of the ooip from offset producers in contacted zone. The water cut reduced from 90% to 45% in the confined producer and from 87% to 67% in the offset producers. Water cut reduction and therefore the oil response is greater than best pilots in the literature. This can be explained because of the cross flow between fluvial layers in the inter-well region. Our simulations indicated that there was no out-flow of the central pattern. The very good performance in terms of low utility factor obtained so far (2.9 kg per incremental barrel of oil above water flooding) supports the hypothesis of the good confinement. The accurate simulation model allowed us to conceptualise a pattern rolling strategy for the polymer expansion that makes this technology economic for this low oil price context.

Maintaining efficient oil production from horizontal wells with varying reservoir properties is a significant challenge. In such scenarios, water breakthroughs can occur prematurely, hindering hydrocarbon recovery. Traditional completion techniques often lack the ability to effectively address this heterogeneity and achieve optimal water control. Autonomous Inflow Control Devices (AICDs) offer an innovative solution for mitigating water influx in horizontal wells. This downhole device automatically regulates fluid flow based on predefined parameters, enabling proactive water control and improved sweep efficiency. This paper presents a successful field case study utilizing RCP AICDs to control water production in a low-viscosity oil reservoir (1.47 cP) offshore China. The paper explores not only the optimal design workflow and value justification for AICDs but also the challenges that led operators to embrace this technology. This paper also emphasizes that to achieve the best results from the use of such technologies, it is essential not only to ensure optimal design but also to operate the wells under conditions that allow the AICD to perform at its highest efficiency. Notably, when AICDs were operated under optimum conditions in this study, the water cut exhibited a continuous declining trend since then, indicating sustained and greater water control effectiveness. This case study demonstrates the effectiveness of AICD technology in controlling water production as water cut reduction was observed at both the mid and later production stages in edge and bottom water reservoirs with low-viscosity crude oil. The well with AICD completion has managed, so far, to deliver 310% increase in cumulative oil production from the well compared to basecase/analogue wells while also extending the well life twice as much than expected. The well's actual cumulative oil production significantly surpassed pre-drilling predictions, reaching over 63,500 m3 and continuing. The implemented RCP AICDs played a crucial role in enhancing water control, improved reservoir management and oil production throughout the well's lifecycle. By effectively controlling water influx in a reservoir with exceptionally low oil viscosity, this pushes the boundaries of AICD applicability. This study offers valuable insights into how these devices can improve field development strategies by mitigating water production and reducing operating costs for lifting, processing and disposal of water plus greenhouse gas emission and energy consumption associated with the operations.

The Bahrain Oil Field was the first oil discovery in the Gulf Region in 1932 and is now in a mature stage of development. Crestal gas injection in the oil bearing, under saturated, layered and heavily faulted carbonate Mauddud reservoir has continued to be the dominant drive mechanism since 1938. Thirty eight 40 acre 5-spot waterflood patterns were implemented from 2011 to 2012. These patterns were located in both the South East and North West part of the Mauddud reservoir with a maximum injection rate of 80,000 bbl/day. With less than 10% PV water injected as of December 2012, premature water breakthrough was observed in most of the producers. Rapid water breakthrough in Mauddud A (Ba) is attributed to presence of high permeability vugs and layers resulting in water cycling and poor sweep in the matrix leaving bypassed oil. Following recommendations from the 2013 partner Peer Assist, the South East and North West waterfloods have been converted from pattern to peripheral with downdip wells providing water injection. Peripheral re-alignment has arrested the production decline, reduced water cut and stabilized production. Surveillance data such as bottomhole pressure data, production logs, reservoir saturation logs, temperature logs and tracer data form the basis of understanding waterflood performance. Additionally, an array of analytical tools were used for diagnosis and analysis. Amongst the diagnostic tools, the Y- function helped to understand water cycling and sweep; the modified-Hall plot assisted in understanding the high-permeability channel or lack thereof and the water-oil-ratio (WOR) provided the clue on fluid displacement. Additional plots such as the "X" plot, decline curve, Cobb plot, pore volume injected vs. recovery, Jordan plot, and Stagg's plot were generated to gain insight on the waterflood. Based on the waterflood analysis, a field study was initiated in December 2016 by shutting more than 80% of water injection followed by complete shut-in in September 2017. The purpose was to reduce the water cut, improve production taking advantage of gravity drainage effect of gas injectors located up dip of waterflood areas. The implementation of water injection shut-in is still ongoing in the Bahrain Field and pressure/production performance is being closely monitored. Improved production performance is observed following water injection shut-in. This study underscores the importance of modern analytical tools to diagnose and analyze waterflood performance. This understanding also paves the way for much improved learning to take appropriate actions and help devise long-term reservoir management strategy.

Scheduling scientific workflows in cloud environments is challenging due to the need to balance multiple objectives while satisfying various constraints. In this paper, we propose a Hybrid cloud Economic and Secure workflow scheduling system (HyEcoSec) designed to minimize makespan and cost while ensuring security and meeting budget and deadline constraints. HyEcoSec comprises two modules: a Security Compliance Module to manage user-defined security requirements, and a Scheduling Module integrating a static scheduler based on the Multi-Portions Slime Mould Algorithm (MPSMA) and a dynamic re-scheduler to handle runtime failures. MPSMA, an enhanced version of the Slime Mould Algorithm (SMA), balances makespan and cost using a modified Pareto approach under budget and deadline constraints. Performance evaluation using the WorkowSim demonstrates the effectiveness of HyEcoSec. Compared to baseline methods, MPSMA achieves a competitive execution time, reduces makespan by 26% and cost by 43%, and improves resource utilization by 22%. It ensures compliance with budget and deadline constraints in almost all cases, outperforming the compared algorithms. The integration of security services shows minimal cost and time impact, confirming HyEcoSec's suitability for secure environments. Furthermore, the dynamic re-scheduler enhances execution efficiency, reducing makespan by 61% and cost by 49% in failure scenarios.

Landscape irrigation systems serve the purpose of lifeline for urban agriculture and horticulture activities such as golf courses, theme parks, airport turfing, traffic islands, surface and rooftop gardening in commercial complexes. A Landscape irrigation system is essentially a pressure irrigation system comprising pop up sprinklers, micro sprinklers and hydrants. The hydraulics involved is very complex due to undulating nature of landscapes. The performance of the pop-up sprinkler used in irrigation of landscaping project (University Auditorium, TNAU) was evaluated. The main analysis examined the relationship between flow-pressure, profile of distribution of water and Christiansen's Uniformity Coefficient (CUC) related with flow pressure. The value of CUC was observed more than 94 percent.

Gravity drip system of irrigation is a cheap, efficient and precised way of providing irrigation water for the kitchen garden. The system is simple to develop, install, operate and very much cater to the need of urban as well as rural kitchen gardening and needs of small and marginal farmers under Badi system of cultivation. It is especially suitable for un-electrified as well as unreliable electric supply area. However, its hydraulic performance needs to be assessed before being used in the kitchen garden for smooth and precise application of water and nutrient. In this study a gravity drip system of irrigation was developed and its hydraulic performance has been evaluated. The system was developed with a platform supported by a frame of 2.55 m height, an overhead tank of 750 liter, 20 m sub main of 63 mm diameter, 200 m lateral of 16 mm with 1.3 lph rated discharge, control valve, flush valve, 10 nos. lateral filters, 10 nos. lateral valves, end caps etc. for a plot of 100 sq. m. (20m × 5m). Hydraulic performance of the system was then evaluated on levelled field at Department of Soil and Water Engineering, IGKV, Raipur, in terms of effect of pressure (head) on discharge, manufacturing coefficient of variation, mean flow rate deviation, uniformity coefficient, application efficiency and distribution efficiency at the falling head of 3.55 m to 2.60 m from the emitting surface. Coefficient of variation, emitter flow variation, uniformity coefficient, application efficiency and distribution efficiency was found to be 4.77%, 14.54%, 95.23%, 91.21% and 95.97% which are in the acceptable limits.