Application of Integrated Far-Field Diversion Technology in Multistage Acid-Fracturing: Lesson Learnings from Unconventional Field North Kuwait

2022 ◽  
Author(s):  
Abdullah Al-Enezi ◽  
Mohammed Al-Othman ◽  
Mishari Al-Shtail ◽  
Yousef Al-Sadeeqi ◽  
Kutbuddin Bhatia ◽  
...  

Abstract The unconventional Bahrah field is a high potential field which poses several challenges in terms of hydrocarbon flow assurance through highly heterogeneous tight carbonate intervals with poor reservoir quality and curtailed mobility. Due to this, the field development strategies have prioritized well completion using horizontal acid fracturing technology over vertical wells. During fracturing, the acid system tends to form highly conductive channels in the formation. Most of the fluid will flow into the path of least resistance leaving large portions of the formation untreated. As a result, the fracturing treatment options dwindle significantly, thus reservoir stimulation results are not optimum in each stage. Achieving complete wellbore coverage is a challenge for any acid frac treatment performed in long lateral with variations in reservoir characteristics. The multistage acid fracturing using Integrated Far-field Diversion (IFD) is performed using selective openhole completion, enabling mechanical annular segmentation of the wellbore using swellable packers and sliding sleeves. The mechanical as well as chemical diversion in IFD methodology is highly important to the overall stimulation success. The technique includes pumping multiple self-degrading particle sizes, considering the openhole annular space and wide presence of natural fractures, followed by in-situ HCL based crosslinked system employed for improving individual stage targets. A biomodal strategy is employed wherein larger particles are supplemented with smaller that can bridge pore throats of the larger particles and have the desired property of rigidity and develop a level of suppleness once exposed to reservoir conditions. The IFD diversion shifts the fracture to unstimulated areas to create complex fractures that increase reservoir contact volume and improving overall conductivity. This paper examines IFD in acid fracturing and describes the crucial diversion strategy. Unlike available diverters used in other fields, the particulates are unaffected at low pH values and in live acids. Proper agent selection and combination with in-situ crosslink acid effectively plug the fracture generated previously and generate pressure high enough to initiate another fracture for further ramification. The optimization and designing of the IFD diversion in each stage plays a key role and has helped to effectively plug fractures and realize segmentation. Concentration of diversion agents, volume of fluid system and open-hole stage length sensitivity plays vital role for the success of this treatment. The application of IFD methodology is tuned as fit-for-purpose to address the unique challenges of well operations, formation technical difficulties, high-stakes economics, and untapped high potential from this unconventional reservoir. A direct result of this acid fracturing treatment is that the post-operation data showed high contribution of all fractured zones along the section in sustained manner. Furthermore, this methodology can be considered as best practice for application in unconventional challenges in other fields.

2021 ◽  
Author(s):  
Abdullah Abu-Eida ◽  
Salem Al-Sabea ◽  
Milan Patra ◽  
Bader Akbar ◽  
Kutbuddin Bhatia ◽  
...  

Abstract The Minagish field in West Kuwait is a high potential field which poses several challenges in terms of hydrocarbon flow assurance through highly depleted tight carbonate intervals with uneven reservoir quality and curtailed mobility. These conditions have shifted the field development from vertical to horizontal wellbore completions. Achieving complete wellbore coverage is a challenge for any frac treatment performed in a long openhole lateral with disparities in reservoir characteristics. The fluid will flow into the path of least resistance leaving large portions of the formation untreated. As a result, economic fracturing treatment options dwindle significantly, thus reservoir stimulation results are not always optimum. A multistage fracturing technique using Integrated Dynamic Diversion (IDD) has been performed first time in West Kuwait field well. The process uses active fluid energy to divert flow into a specific fracture point in the lateral, which can initiate and precisely place a fracture. The process uses two self-directed fluid streams: one inside the pipe and one in the annulus. The process mixes the two fluids downhole with high energy to form a consistent controllable mixture. The technique includes pinpoint fluid jetting at the point of interest, followed by in-situ HCL based crosslinked systems employed for improving individual stage targets. The IDD diversion shifts the fracture to unstimulated areas to create complex fractures which increases reservoir contact volume and improved overall conductivity in the lateral. The kinetic and chemical diversion of the IDD methodology is highly critical to control fluid loss in depleted intervals and results in enhanced stimulation. Pumping a frac treatment in openhole without control would tend to initiate a longitudinal fracture along the wellbore and may restrict productivity. By using specialized completion tools with nozzles at the end of the treating string, a new pinpoint process has been employed to initiate a transverse fracture plane in IDD applications. Proper candidate selection and fluid combination with in-situ crosslink acid effectively plug the fracture generated previously and generate pressure high enough to initiate another fracture for further ramification. By combining these processes into one continuous operation, the use of wireline/coiled tubing for jetting, plug setting and milling is eliminated, making the new multistage completion technology economical for these depleted wells. The application of the IDD methodology is a fit-for-purpose solution to address the unique challenges of openhole operations, formation technical difficulties, high-stakes economics, and untapped high potential from intermittent reservoirs. The paper will present post-operation results of this completion from all fractured zones along the lateral and will describe the lessons learned in implementation of this methodology which can be considered as best practice for application in similar challenges in other fields.


2021 ◽  
Author(s):  
Salem Al-Sabea ◽  
Abdullah Abu-Eida ◽  
Milan Patra ◽  
Yousef Haider ◽  
Hasan Al Qattan ◽  
...  

Abstract The Minagish field in West Kuwait is a high potential field which poses several challenges in terms of hydrocarbon flow assurance through highly depleted tight carbonate intervals with uneven reservoir quality and curtailed mobility. These conditions have shifted the field development from vertical to horizontal wellbore completions. Achieving complete wellbore coverage is a challenge for any Matrix Acid treatment performed in a long openhole lateral with disparities in reservoir characteristics. The fluid will flow into the path of least resistance leaving large portions of the formation untreated. As a result, economic Acid treatment options dwindle significantly, thus reservoir stimulation results are not always optimum. A multistage acid stimulation technique using Integrated Dynamic Diversion (IDD) has been performed in a West Kuwait field well. The process uses active fluid energy to divert flow into a specific sweet point (high pressure point) in the lateral, which can pinpoint and precisely place acid treatment at the desired location. The process uses two self-directed fluid streams: one inside the pipe and one in the annulus. The process mixes the two fluids downhole with high energy to form a consistent controllable mixture. The technique includes pinpoint fluid jetting at the point of interest, followed by customized foamed HCL acid systems employed for improving individual stage targets in depleted reservoir. The IDD diversion shifts the acid treatment to unstimulated areas to create complex wormholes which increase reservoir contact volume and improve overall conductivity in the lateral. The kinetics and chemical diversion of the IDD methodology are highly critical to control fluid loss in depleted intervals and results in enhanced stimulation. The application of the IDD methodology is a fit-for-purpose solution to address the unique challenges of openhole operations, formation technical difficulties, high-stakes economics, and untapped high potential from intermittent reservoirs. By utilizing this application in one continuous operation, the use of chemical diverters, straddle packers and mechanical plugs for selective treatment in open hole is eliminated, making this multistage completion technology economical for these depleted wells. The paper presents results obtained after stimulating multiple zones along the lateral and describes the lessons learned in the implementation of this methodology. Going forward, the methods described, which can be considered a best practice for application to similar challenges in other fields. Proper candidate selection, optimum completion tools, and the fluid combination of in-situ gel-based diverter used to temporary plug the acid stimulated zone and foamed acid created an increase in the oil production of 430 BOPD.


2019 ◽  
Vol 11 (19) ◽  
pp. 5283 ◽  
Author(s):  
Gowida ◽  
Moussa ◽  
Elkatatny ◽  
Ali

Rock mechanical properties play a key role in the optimization process of engineering practices in the oil and gas industry so that better field development decisions can be made. Estimation of these properties is central in well placement, drilling programs, and well completion design. The elastic behavior of rocks can be studied by determining two main parameters: Young’s modulus and Poisson’s ratio. Accurate determination of the Poisson’s ratio helps to estimate the in-situ horizontal stresses and in turn, avoid many critical problems which interrupt drilling operations, such as pipe sticking and wellbore instability issues. Accurate Poisson’s ratio values can be experimentally determined using retrieved core samples under simulated in-situ downhole conditions. However, this technique is time-consuming and economically ineffective, requiring the development of a more effective technique. This study has developed a new generalized model to estimate static Poisson’s ratio values of sandstone rocks using a supervised artificial neural network (ANN). The developed ANN model uses well log data such as bulk density and sonic log as the input parameters to target static Poisson’s ratio values as outputs. Subsequently, the developed ANN model was transformed into a more practical and easier to use white-box mode using an ANN-based empirical equation. Core data (692 data points) and their corresponding petrophysical data were used to train and test the ANN model. The self-adaptive differential evolution (SADE) algorithm was used to fine-tune the parameters of the ANN model to obtain the most accurate results in terms of the highest correlation coefficient (R) and the lowest mean absolute percentage error (MAPE). The results obtained from the optimized ANN model show an excellent agreement with the laboratory measured static Poisson’s ratio, confirming the high accuracy of the developed model. A comparison of the developed ANN-based empirical correlation with the previously developed approaches demonstrates the superiority of the developed correlation in predicting static Poisson’s ratio values with the highest R and the lowest MAPE. The developed correlation performs in a manner far superior to other approaches when validated against unseen field data. The developed ANN-based mathematical model can be used as a robust tool to estimate static Poisson’s ratio without the need to run the ANN model.


2021 ◽  
Author(s):  
Ali Abdullah Al-Azmi ◽  
Thanyan Ahmed Al-Yaqout ◽  
Dalal Yousef Al-Jutaili ◽  
Kutbuddin Bhatia ◽  
Amr Abdelbaky ◽  
...  

Abstract Excessive water production from hydrocarbon reservoirs is a serious issue faced by the industry, particularly for mature fields. Higher water cut adversely affects the economics of the producing wells, thus it is undesirable. Disposal and reinjection of ever-increasing volumes of produced water poses additional liability. A significant challenge faced in the mature Umm Gudair field is assuring hydrocarbon flow through high water-prone intervals. In recent times, field development strategies have begun to prioritize new well intervention technology because of the advantages of minimized water cut, higher production rates, and improved overall reserve recovery (hydrocarbon in place). This paper discusses the field implementation of a downhole chemical methodology, "first of its kind" designed and applied, that has created a positive impact in overall productivity. To solve these challenges, the treatment was highly modified as fit-for-purpose to address the unique challenges of electric submersible pump (ESP)-driven well operations, formation technical difficulties, high-stakes economics, and high-water potential from these formations. A unique Organically Crosslinked Polymer (OCP) system with a tail-in Rigid Setting Material (RSM) system was implemented as a porosity-fill sealant in a high-water-cut well to selectively reduce water production. A pre-flush was pumped ahead of the treatment to remove deposits that could have prevented the polymer from effective gelation. The treatment was then overdisplaced with brine. The OCP system is injected into the formation as a low viscosity solution using the spot and hesitation squeeze method via bullheading. It activates at a predicted time to form a 3-D rigid hydrogel to completely shut off matrix permeability, fractures, fissures, and channels, thus creating an artificial barrier seal in the reservoir. The tail-in near wellbore RSM system rapidly develops a high compressive strength to avoid any formation loss before setting. This holistic approach helps to create a robust sealant for blocking the unwanted water-producing zone, impeding water flow, and facilitating increased hydrocarbon flow. A direct comparison of the application of this system with conventional cement squeeze treatments is presented to illustrate the advantage of having a deep matrix penetration for a more efficient water shutoff in this field. A direct result of the implemented treatment is that the post-operation well test and production data showed a high-sustained production at lower rate with significantly reduced watercut, confirming this technology is one of successful chemical water shut off techniques this field. This paper summarizes the candidate selection, design processes, challenges encountered, and production response, and can be considered a best practice for addressing high water production challenges in similar conditions in other fields.


1982 ◽  
Vol 14 (3) ◽  
pp. 33-39
Author(s):  
C Y Kuo

An existing, three-dimensional, Eulerian-Lagrangian finite-difference model was modified and used to examine the far-field transport processes of dumped sewage sludge in the New York Bight. Both in situ and laboratory data were utilized in an attempt to approximate model inputs such as mean current speed, vertical and horizontal diffusion coefficients, particle size distributions, and specific gravities. Concentrations of the sludge near the sea surface predicted from the computer model were compared qualitatively with those remotely sensed.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Juan Zhao ◽  
Hui Li ◽  
Guangxin Chen ◽  
Lijun Du ◽  
Peiyan Xu ◽  
...  

Abstract Background Aneuploidy is the most frequent cause of early-embryo abortion. Any defect in chromosome segregation would fail to satisfy the spindle assembly checkpoint (SAC) during mitosis, halting metaphase and causing aneuploidy. The mitotic checkpoint complex (MCC), comprising MAD1, MAD2, Cdc20, BUBR1 and BUB3, plays a vital role in SAC activation. Studies have confirmed that overexpression of MAD2 and BUBR1 can facilitate correct chromosome segregation and embryo stability. Research also proves that miR-125b negatively regulates MAD1 expression by binding to its 3′UTR. However, miR-125b, Mad1 and Bub3 gene expression in aneuploid embryos of spontaneous abortion has not been reported to date. Methods In this study, embryonic villi from miscarried pregnancies were collected and divided into two groups (aneuploidy and euploidy) based on High-throughput ligation-dependent probe amplification (HLPA) and Fluorescence in situ hybridization (FISH) analyses. RNA levels of miR-125b, MAD1 and BUB3 were detected by Quantitative real-time PCR (qRT-PCR); protein levels of MAD1 and BUB3 were analysed by Western blotting. Results statistical analysis (p < 0.05) showed that miR-125b and BUB3 were significantly down-regulated in the aneuploidy group compared to the control group and that MAD1 was significantly up-regulated. Additionally, the MAD1 protein level was significantly higher in aneuploidy abortion villus, but BUB3 protein was only mildly increased. Correlation analysis revealed that expression of MAD1 correlated negatively with miR-125b. Conclusion These results suggest that aneuploid abortion correlates positively with MAD1 overexpression, which might be caused by insufficient levels of miR-125b. Taken together, our findings first confirmed the negative regulatory mode between MAD1 and miR-125b, providing a basis for further mechanism researches in aneuploid abortion.


2020 ◽  
Vol 12 (17) ◽  
pp. 2861
Author(s):  
Jifu Yin ◽  
Xiwu Zhan ◽  
Jicheng Liu

Soil moisture plays a vital role for the understanding of hydrological, meteorological, and climatological land surface processes. To meet the need of real time global soil moisture datasets, a Soil Moisture Operational Product System (SMOPS) has been developed at National Oceanic and Atmospheric Administration to produce a one-stop shop for soil moisture observations from all available satellite sensors. What makes the SMOPS unique is its near real time global blended soil moisture product. Since the first version SMOPS publicly released in 2010, the SMOPS has been updated twice based on the users’ feedbacks through improving retrieval algorithms and including observations from new satellite sensors. The version 3.0 SMOPS has been operationally released since 2017. Significant differences in climatological averages lead to remarkable distinctions in data quality between the newest and the older versions of SMOPS blended soil moisture products. This study reveals that the SMOPS version 3.0 has overwhelming advantages of reduced data uncertainties and increased correlations with respect to the quality controlled in situ measurements. The new version SMOPS also presents more robust agreements with the European Space Agency’s Climate Change Initiative (ESA_CCI) soil moisture datasets. With the higher accuracy, the blended data product from the new version SMOPS is expected to benefit the hydrological, meteorological, and climatological researches, as well as numerical weather, climate, and water prediction operations.


2007 ◽  
Author(s):  
Ken E.T. Halward ◽  
Joe Emery ◽  
Rod Christensen ◽  
Daniel Joseph Bourgeois ◽  
Grant Skinner ◽  
...  

SPE Journal ◽  
2013 ◽  
Vol 18 (03) ◽  
pp. 440-447 ◽  
Author(s):  
C.C.. C. Ezeuko ◽  
J.. Wang ◽  
I.D.. D. Gates

Summary We present a numerical simulation approach that allows incorporation of emulsion modeling into steam-assisted gravity-drainage (SAGD) simulations with commercial reservoir simulators by means of a two-stage pseudochemical reaction. Numerical simulation results show excellent agreement with experimental data for low-pressure SAGD, accounting for approximately 24% deficiency in simulated oil recovery, compared with experimental data. Incorporating viscosity alteration, multiphase effect, and enthalpy of emulsification appears sufficient for effective representation of in-situ emulsion physics during SAGD in very-high-permeability systems. We observed that multiphase effects appear to dominate the viscosity effect of emulsion flow under SAGD conditions of heavy-oil (bitumen) recovery. Results also show that in-situ emulsification may play a vital role within the reservoir during SAGD, increasing bitumen mobility and thereby decreasing cumulative steam/oil ratio (cSOR). Results from this work extend understanding of SAGD by examining its performance in the presence of in-situ emulsification and associated flow of emulsion with bitumen in porous media.


2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Richard J. Lee ◽  
Laura A. Vallow ◽  
Sarah A. McLaughlin ◽  
Katherine S. Tzou ◽  
Stephanie L. Hines ◽  
...  

Ductal carcinoma in situ (DCIS) of the breast represents a complex, heterogeneous pathologic condition in which malignant epithelial cells are confined within the ducts of the breast without evidence of invasion. The increased use of screening mammography has led to a significant shift in the diagnosis of DCIS, accounting for approximately 27% of all newly diagnosed cases of breast cancer in 2011, with an overall increase in incidence. As the incidence of DCIS increases, the treatment options continue to evolve. Consistent pathologic evaluation is crucial in optimizing treatment recommendations. Surgical treatment options include breast-conserving surgery (BCS) and mastectomy. Postoperative radiation therapy in combination with breast-conserving surgery is considered the standard of care with demonstrated decrease in local recurrence with the addition of radiation therapy. The role of endocrine therapy is currently being evaluated. The optimization of diagnostic imaging, treatment with regard to pathological risk assessment, and the role of partial breast irradiation continue to evolve.


Sign in / Sign up

Export Citation Format

Share Document