Gels for Oil Drilling and Enhanced Recovery (2nd Edition)

A special issue of Gels (ISSN 2310-2861). This special issue belongs to the section "Gel Applications".

Deadline for manuscript submissions: closed (31 January 2024) | Viewed by 13934

Special Issue Editors


E-Mail Website
Guest Editor
College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing 102249, China
Interests: microscopic seepage; EOR; unconventional reservoir
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 257099, China
Interests: polymer gel; drilling fluid; lost circulation control; conformance control; water shutoff; enhanced oil recovery
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue is focused on the study of organic and inorganic gels in oil–gas fields to improve drilling efficiency and enhance oil recovery. A broad range of topics will be discussed, including, but not limited to, novel gel synthesis, the mathematical simulation and experimental evaluation of gel performance, the application of gels for improving drilling efficiency and enhancing oil recovery, etc.

Gels are elastomers with a three-dimensional (3D) network structure that is composed of polymers and cross-linkers as the main agents, along with other additives. They have been widely used in various aspects of oil–gas drilling and production engineering, such as drilling fluid, lost circulation control, fracturing, acidizing, conformance control, water shutoff, and enhanced oil recovery.

Gels in oil–gas reservoirs are often subjected to high temperatures and salinity, and excessive temperatures and salinity can destroy the structural integrity of the polymer chains, resulting in a substantial decrease in stability. Therefore, maintaining the good properties of gels under high-temperature and high-salinity conditions is extremely difficult. Therefore, efforts should be made to synthesize novel gels, evaluate the physical and chemical properties of gels in high-temperature and high-salinity conditions, and investigate the application effects of gels in the drilling and enhanced oil recovery processes in the lab. In addition, owing to the complexity of the reservoirs, some gels may perform differently in the field than in the lab. In this case, the experiences gained from field application studies are very valuable for future gel development, evaluation, and application.

We are looking forward to the submission of new studies on organic or inorganic gels to improve drilling efficiency and enhance oil recovery.

Prof. Dr. Junjian Li
Dr. Yingrui Bai
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Gels is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • gel synthesis
  • gel evaluation
  • gel drilling fluids
  • gel plugging
  • gel fracturing fluid
  • gel acid
  • gel conformance control
  • gel displacement
  • gel application

Related Special Issue

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

16 pages, 3806 KiB  
Article
An Innovative High-Strength Double-Network Hydrogel for Use as a Drilling Fluid Plugging Agent
by Yanfeng He, Jing Guo, Jinmei Bai, Le Hua, Yisong Zhang, Zhiqiang Huang, Letian Pan and Zhan Hong
Gels 2024, 10(4), 224; https://doi.org/10.3390/gels10040224 - 25 Mar 2024
Viewed by 557
Abstract
The problem of wellbore leakage is a key challenge in the petroleum industry, limiting drilling progress and increasing drilling costs. Plugging agents play a role in repairing leaks and fractures; however, traditional plugging materials generally have low mechanical strength, poor adaptability to permeable [...] Read more.
The problem of wellbore leakage is a key challenge in the petroleum industry, limiting drilling progress and increasing drilling costs. Plugging agents play a role in repairing leaks and fractures; however, traditional plugging materials generally have low mechanical strength, poor adaptability to permeable strata, limited water absorption and expansion capabilities, and poor temperature and salt resistance. To address these limitations, a pioneering polyacrylic acid-polyacrylamide (PAA/PAM) double-network hydrogel was synthesized through aqueous solution polymerization in this study. Its strength, water absorption, expansion, temperature resistance, salt resistance, and plugging effectiveness were comprehensively evaluated. The results demonstrate that good mechanical performance is exhibited by the synthesized hydrogel, capable of withstanding a maximum stress of approximately 3.5 MPa at a 90% strain. Excellent water absorption and expansion are observed in the synthesized double-network hydrogel, with a maximum expansion of 6 times within 30 min and 8 times after 2 h. Test results show that the hydrogel had good temperature resistance and salt resistance, maintaining a strength grade E within the experimental range. The simulated evaluation of the plugging experiment indicates that, under conditions of 130 °C and 6 MPa, the leakage rate of the drilling fluid is maintained below 5 mL/min when the double-network hydrogel is utilized. From the above experimental results, it can be illustrated that excellent mechanical properties, impressive water absorption, and expansion capabilities are exhibited by the synthesized double-network hydrogel. Furthermore, the high-temperature resistance and salt resistance of the double-network hydrogel were also demonstrated. Therefore, In comparison to traditional plugging materials, significant promise is held by this newly synthesized double-network hydrogel material as a plugging agent in drilling fluids. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

22 pages, 6454 KiB  
Article
Use of Self-Generating Foam Gel Composition with Subsequent Injection of Hydrogel to Limit Gas Inflow in Horizontal Wells of Vostochno-Messoyakhskoye Field
by Aleksey Telin, Dmitriy Karazeev, Sergey Vezhnin, Vladimir Strizhnev, Aleksey Levadsky, Anton Mamykin, Lyubov Lenchenkova, Ravil Yakubov, Alsu Fakhreeva, Alfir Akhmetov, Aleksey Oleynik, Anton Shirobokov, Bulat Minnebaev, Ilyas Mullagalin and Ramil Bakhtizin
Gels 2024, 10(4), 215; https://doi.org/10.3390/gels10040215 - 22 Mar 2024
Viewed by 725
Abstract
Gas inflow control in oil wells is one of the most challenging types of repair and sealing operations, the success rate of which does not exceed, as a rule, 30%. Conventional shutoff methods are often ineffective for this purpose. For instance, cement solutions [...] Read more.
Gas inflow control in oil wells is one of the most challenging types of repair and sealing operations, the success rate of which does not exceed, as a rule, 30%. Conventional shutoff methods are often ineffective for this purpose. For instance, cement solutions cannot be injected into wells in the required volumes, while gel screens can only temporarily block the breakthrough zones, as gas easily seeps through the gel, forming new channels for gas inflow. Technology for the two-stage injection of gas-insulating gel systems for gas control in horizontal wells was developed. At the first stage, a self-generating foam gel composition (FGC), consisting of gel-forming and gas-forming compositions, was used. A foam gel structure with enhanced rheological and flow characteristics was formed over a controlled time as a result of the interaction between the gel-forming and gas-forming compounds. A PAM-based hydrogel crosslinked with an organic crosslinker was added to the FGC at the second stage of treatment. The laboratory experiments substantiated the technology of well gas and water shutoff by the sequential injection of self-generating foam gel composition and hydrogel. Field tests confirmed the correctness of the chosen concept. It is very important to clearly identify the sources of gas inflow for the success of this well intervention and take into account the well design, as well as the reservoir geological structure and characteristics. The gas shutoff operation can be properly designed for each well only by comparing all these factors. The validity of the selected technology was tested through a series of laboratory experiments. Successful laboratory tests allowed for the application of the studied technology in a field setting, where the gas shutoff agent was injected into three horizontal wells. As a result of the field application, the gas inflow was successfully isolated in two wells. However, the application of the technology failed in the third well which gave an opportunity to revisit the technology’s design and to review the sources of gas inflow. Overall, the achieved success rate of 66% demonstrated the high efficiency of the studied technology and supported its wider application in the field. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

16 pages, 7885 KiB  
Article
The Simulation of Ester Lubricants and Their Application in Weak Gel Drilling Fluids
by Yao Dai, Fuwei Lu, Yuhua Tang, Yuanyuan Wang, Xinyi He, Tengfei Wang and Juan Wu
Gels 2024, 10(3), 178; https://doi.org/10.3390/gels10030178 - 03 Mar 2024
Viewed by 830
Abstract
To enhance the performance and reduce the amount of ester-based lubricants used in weak gel drilling fluids, a shear dynamics simulation under extreme pressure conditions was employed to refine the formulation of the base oil and pressure additives. The simulation results were validated [...] Read more.
To enhance the performance and reduce the amount of ester-based lubricants used in weak gel drilling fluids, a shear dynamics simulation under extreme pressure conditions was employed to refine the formulation of the base oil and pressure additives. The simulation results were validated using fatty acid methyl, ethyl, and butyl esters. Fatty acid methyl ester demonstrated the lowest temperature increase and the highest load-bearing capacity post-shear. The four-ball friction test revealed that methyl oleate had a coefficient of friction of 0.0018, approximately a third of that for butyl oleate, confirming the simulation’s accuracy. By using methyl oleate as the base oil and oleamide as the pressure-resistant component, the optimal shear stress was achieved with a 10% addition of oleamide. A lubricant composed of 90% methyl oleate and 10% oleamide was tested and showed a coefficient of friction of 0.03 when 0.5% was added to bentonite slurry, indicating a strong lubricating film. Adding 1% of this lubricant to a low gel drilling fluid system did not affect its rheological properties, and the gel structure remained stable after seven days of aging. Field tests at the Fu86-3 well in the Jiangsu Oilfield of Sinopec confirmed that adding 1% of the ester-based lubricant to the drilling fluid significantly improved drilling efficiency, reduced drag by an average of 33%, and increased the drilling rate to 22.12 m/h. This innovation effectively prevents drilling complications and successfully achieves the objectives of enhancing efficiency. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Graphical abstract

15 pages, 6110 KiB  
Article
Preparation and Performance Evaluation of Ionic Liquid Copolymer Shale Inhibitor for Drilling Fluid Gel System
by Zhiwen Dai, Jinsheng Sun, Zhuoyang Xiu, Xianbin Huang, Kaihe Lv, Jingping Liu, Yuanwei Sun and Xiaodong Dong
Gels 2024, 10(2), 96; https://doi.org/10.3390/gels10020096 - 26 Jan 2024
Viewed by 896
Abstract
An inhibitor that can effectively inhibit shale hydration is necessary for the safe and efficient development of shale gas. In this study, a novel ionic liquid copolymer shale inhibitor (PIL) was prepared by polymerizing the ionic liquid monomers 1-vinyl-3-aminopropylimidazolium bromide, acrylamide, and methacryloyloxyethyl [...] Read more.
An inhibitor that can effectively inhibit shale hydration is necessary for the safe and efficient development of shale gas. In this study, a novel ionic liquid copolymer shale inhibitor (PIL) was prepared by polymerizing the ionic liquid monomers 1-vinyl-3-aminopropylimidazolium bromide, acrylamide, and methacryloyloxyethyl trimethyl ammonium chloride. The chemical structure was characterized using fourier transform infrared spectroscopy (FT-IR) and hydrogen-nuclear magnetic resonance (H-NMR), and the inhibition performance was evaluated using the inhibition of slurrying test, bentonite flocculation test, linear expansion test, and rolling recovery test. The experimental results showed that bentonite had a linear expansion of 27.9% in 1 wt% PIL solution, 18% lower than that in the polyether amine inhibitor. The recovery rate of shale in 1 wt% PIL was 87.4%. The ionic liquid copolymer could work synergistically with the filtrate reducer, reducing filtration loss to 7.2 mL with the addition of 1%. Mechanism analysis showed that PIL adsorbed negatively charged clay particles through cationic groups, which reduced the electrostatic repulsion between particles. Thus, the stability of the bentonite gel systems was destroyed, and the hydration dispersion and expansion of bentonite were inhibited. PIL formed a hydrophobic film on the surface of clay and prevented water from entering into the interlayer of clay. In addition, PIL lowered the surface tension of water, which prevented the water from intruding into the rock under the action of capillary force. These are also the reasons for the superior suppression performance of PIL. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Graphical abstract

16 pages, 7192 KiB  
Article
A Self-Healing Gel with an Organic–Inorganic Network Structure for Mitigating Circulation Loss
by Cheng Wang, Jinsheng Sun, Yifu Long, Hongjun Huang, Juye Song, Ren Wang, Yuanzhi Qu and Zexing Yang
Gels 2024, 10(2), 93; https://doi.org/10.3390/gels10020093 - 25 Jan 2024
Viewed by 948
Abstract
Lost circulation control remains a challenge in drilling operations. Self-healing gels, capable of self-healing in fractures and forming entire gel block, exhibit excellent resilience and erosion resistance, thus finding extensive studies in lost circulation control. In this study, layered double hydroxide, Acrylic acid, [...] Read more.
Lost circulation control remains a challenge in drilling operations. Self-healing gels, capable of self-healing in fractures and forming entire gel block, exhibit excellent resilience and erosion resistance, thus finding extensive studies in lost circulation control. In this study, layered double hydroxide, Acrylic acid, 2-Acrylamido-2-methylpropane sulfonic acid, and CaCl2 were employed to synthesize organic-inorganic nanocomposite gel with self-healing properties. The chemical properties of nanocomposite gels were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, X-ray photoelectron spectroscopy and thermogravimetric analysis. layered double hydroxide could be dispersed and exfoliated in the mixed solution of Acrylic acid and 2-Acrylamido-2-methylpropane sulfonic acid, and the swelling behavior, self-healing time, rheological properties, and mechanical performance of the nanocomposite gels were influenced by the addition of layered double hydroxide and Ca2+. Optimized nanocomposite gel AC6L3, at 90 °C, exhibits only a self-healing time of 3.5 h in bentonite mud, with a storage modulus of 4176 Pa, tensile strength of 6.02 kPa, and adhesive strength of 1.94 kPa. In comparison to conventional gel, the nanocomposite gel with self-healing capabilities demonstrated superior pressure-bearing capacity. Based on these characteristics, the nanocomposite gel proposed in this work hold promise as a candidate lost circulation material. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

22 pages, 12110 KiB  
Article
Evaluation of Novel Preformed Particle Gel System for Conformance Control in Mature Oil Reservoirs
by Abdulaziz Almakimi, Ahmed Ben Ali, Ibnelwaleed A. Hussein and Baojun Bai
Gels 2024, 10(1), 70; https://doi.org/10.3390/gels10010070 - 17 Jan 2024
Viewed by 920
Abstract
To address challenges associated with excessive water production in mature oil reservoirs, this study introduces a carboxymethyl cellulose (CMC)-based material as a novel preformed particle gel (PPG) designed to plug excessive water pathways and redistribute the subsequent injected water toward unswept zones. Through [...] Read more.
To address challenges associated with excessive water production in mature oil reservoirs, this study introduces a carboxymethyl cellulose (CMC)-based material as a novel preformed particle gel (PPG) designed to plug excessive water pathways and redistribute the subsequent injected water toward unswept zones. Through microwave-assisted grafting copolymerization of CMC with acrylamide (AM), we successfully generated multi-sized dry particles within the range of 250–800 µm. Comprehensive analyses, including Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), have confirmed the chemical composition and morphology of the resulting carboxymethyl cellulose-grafted crosslinked polyacrylamide (CMC/PAMBA). Swelling kinetics and rheology tests were conducted to confirm the ability of this novel PPG system to perform at different reservoir conditions. The results of core flooding experiments showed that the CMC/PAMBA PPG is capable of plugging open fractures with a water breakthrough pressure gradient of up to 144 psi/ft. This preformed particle gel (PPG) system was designed specifically for application in Middle East reservoirs, which are distinguished by high salinity and elevated temperature levels. This PPG system is able to swell up to 10 times its original size in seawater and maintain a strength of about 1300 Pa at a temperature of 80 °C. Further optimization is conceivable to enhance injection efficiency and achieve superior plugging outcomes. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

15 pages, 4810 KiB  
Article
Preparation and Performance of Resin-Gel–Rubber Expandable Lost Circulation Material Blend
by Jinzhi Zhu, Erbiao Lou, Shaojun Zhang, Haiying Lu and Ziwu Wang
Gels 2023, 9(11), 862; https://doi.org/10.3390/gels9110862 - 30 Oct 2023
Viewed by 919
Abstract
Aiming at the complex strata, lost circulation often occurs. and lost circulation control becomes a difficult issue. A drilling fluid loss accident delays the drilling progress and even causes major economic losses. If we take a self-made sodium polyacrylate grafting and modify a [...] Read more.
Aiming at the complex strata, lost circulation often occurs. and lost circulation control becomes a difficult issue. A drilling fluid loss accident delays the drilling progress and even causes major economic losses. If we take a self-made sodium polyacrylate grafting and modify a starch water absorbent resin, using an amphiphilic compatibilizer as raw material through mechanical blending and chemical compatibilization, we can synthesize a resin–rubber blend swelling lost circulation material. This material presents a good resistance to anti-high-temperature performance, but the quality declines while the temperature is higher than 363 °C, and with the increasing temperature, the water-swelling expansion ratio becomes higher. The range of the water-swelling expansion ratio is 8 to 25 times and the water swelling rate becomes larger along with the reduced diameter of the lost circulation materials and decreases with the increasing salinity. The resin-rubber blend swelling lost circulation material after water swelling has excellent toughness and high elastic deformation capacity, thus, forming a 7 Mpa to 2 mm fracture via expansion, extrusion, deformation, and filling, which presents a good performance for fracture plugging and realizes the purpose of lost circulation control. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

13 pages, 6374 KiB  
Article
Development of a Low-Molecular-Weight Filtrate Reducer with High-Temperature Resistance for Drilling Fluid Gel System
by Fengbao Liu, Jinsheng Sun, Xianbin Huang and Yuan Geng
Gels 2023, 9(10), 805; https://doi.org/10.3390/gels9100805 - 07 Oct 2023
Viewed by 945
Abstract
Currently, conventional polymeric filtrate reducers with high-temperature resistance for use in drilling fluids have high molecular weights, which greatly affects the rheological properties. Therefore, to address the challenges in regulating the rheology and filtration performance of high-density drilling fluids at high temperatures, it [...] Read more.
Currently, conventional polymeric filtrate reducers with high-temperature resistance for use in drilling fluids have high molecular weights, which greatly affects the rheological properties. Therefore, to address the challenges in regulating the rheology and filtration performance of high-density drilling fluids at high temperatures, it is essential to develop low-molecular-weight filtrate reducers with high-temperature resistance. In this study, a low-molecular-weight filtrate reducer with high-temperature resistance (LMF) was prepared via free radical polymerization from acrylamide and 2-acrylamido-2-methyl-1-propanesulfonic acid as monomers, tertiary dodecyl mercaptan as a chain transfer agent, and ammonium persulfate as the initiator. LMF was then characterized by infrared spectroscopy, thermogravimetric analysis, and gel permeation chromatography. The obtained filtrate reducer exhibits a weight-average molecular weight (Mw) of 3819 and an initial thermal decomposition temperature of 300.7 °C, indicating good thermal stability. The effects of LMF dosage, temperature, and NaCl dosage on the rheology and filtration performance of mud samples were also investigated, and the mechanism of action was revealed by zeta potential, particle size distribution, scanning electron microscopy, and adsorption measurements. The results reveal that LMF increases the mud sample viscosity and reduces its filtration. For example, the filtration of the mud sample with 2 wt% LMF was 7.2 mL, a reduction of 70% compared to that of a blank mud sample. Further, after aging at 210 °C for 16 h, the filtration of the same sample was 11.6 mL, and that of a mud sample with 2 wt% LMF and 35 wt% NaCl after aging at 180 °C for 16 h was 22 mL. Overall, we have reported a scheme to prepare a low-molecular-weight filtrate reducer with high-temperature resistance and superior filtrate-reducing effects, laying the foundation for the investigation and development of low-molecular-weight filtrate reducers. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Graphical abstract

15 pages, 5600 KiB  
Article
Use of Highly Dispersed Mixed Metal Hydroxide Gel Compared to Bentonite Based Gel for Application in Drilling Fluid under Ultra-High Temperatures
by Bowen Zhang, Qingchen Wang, Xiaofeng Chang, Weichao Du, Fan Zhang, Michal Kuruc, Michal Slaný and Gang Chen
Gels 2023, 9(7), 513; https://doi.org/10.3390/gels9070513 - 25 Jun 2023
Cited by 1 | Viewed by 1311
Abstract
In order to solve the problem of poor dispersion and stability of mixed metal hydroxide (MMH), a kind of mixed metal hydroxide-like compound (MMHlc) gel was synthesized for use as the base mud in drilling fluid instead of bentonite gel. Na2CO [...] Read more.
In order to solve the problem of poor dispersion and stability of mixed metal hydroxide (MMH), a kind of mixed metal hydroxide-like compound (MMHlc) gel was synthesized for use as the base mud in drilling fluid instead of bentonite gel. Na2CO3, Na2SiO3, and C17H33CO2Na were used as precipitants to form MMHlc with larger interlayer spacing and smaller particle size. MMHlc was synthesized by the coprecipitation method at 25 °C with a metal molar ratio of Mg:Al:Fe = 3:1:1. The performance evaluation of the treated drilling fluid showed that MMHlc (S2) synthesized using Na2SiO3 as the precipitant had the characteristics of low viscosity, low filtration, and a high dynamic plastic ratio at 25 °C, which fully met the requirements of oil field application, and it maintained its excellent properties after being aged at 250 °C for 16 h. Linear expansion and rolling recovery experiments showed that the S2 sample had excellent rheological properties and good inhibition. X-ray diffraction and FT-IR experiments showed that S2 had the most complete crystal structure, its interlayer distance was large, and its ion exchange capacity was strong. The thermogravimetric experiment showed that the S2 crystal was stable and the temperature resistance of the crystal could reach 340 °C. Zeta potential, particle size analysis, SEM, and TEM results showed that S2 is a nanomaterial with a complete morphology and uniform distribution. The drilling fluid of this formula had the characteristics of low viscosity, low filtration loss, and a high dynamic plastic ratio, and it met the conditions for oil field application. Considering these results, the new MMH prepared by our research institute is a drilling fluid material that can be used at ultra-high temperatures and can provide important support for drilling ultra-deep wells. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

13 pages, 11488 KiB  
Article
Preparation of Encapsulated Breakers for Polymer Gels and Evaluation of Their Properties
by Kaihe Lv, Guodong Zhang, Yingrui Bai and Jingbin Yang
Gels 2023, 9(5), 387; https://doi.org/10.3390/gels9050387 - 08 May 2023
Cited by 3 | Viewed by 1662
Abstract
A common problem associated with conventional gel breakers is that they can cause a premature reduction in gel viscosity at high temperatures. To address this, a urea-formaldehyde (UF) resin and sulfamic acid (SA) encapsulated polymer gel breaker was prepared via in situ polymerization [...] Read more.
A common problem associated with conventional gel breakers is that they can cause a premature reduction in gel viscosity at high temperatures. To address this, a urea-formaldehyde (UF) resin and sulfamic acid (SA) encapsulated polymer gel breaker was prepared via in situ polymerization with UF as the capsule coat and SA as the capsule core; this breaker was able to withstand temperatures of up to 120–140 °C. The encapsulated breaker was characterized using scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), and thermogravimetric (TG) analysis. Meanwhile, the dispersing effects of various emulsifiers on the capsule core, and the encapsulation rate and electrical conductivity of the encapsulated breaker were tested. The gel-breaking performance of the encapsulated breaker was evaluated at different temperatures and dose conditions via simulated core experiments. The results confirm the successful encapsulation of SA in UF and also highlight the slow-release properties of the encapsulated breaker. From experimentation, the optimal preparation conditions were determined to be a molar ratio between urea and formaldehyde (nurea:nformaldehyde) of 1:1.8 for the capsule coat, a pH of 8, a temperature of 75 °C, and the utilization of Span 80/SDBS as the compound emulsifier; the resulting encapsulated breaker exhibited significantly improved gel-breaking performance (gel breaking delayed for 9 days at 130 °C). The optimum preparation conditions determined in the study can be used in industrial production, and there are no potential safety and environmental concerns. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

Review

Jump to: Research

50 pages, 15295 KiB  
Review
Application of Hydrogels and Hydrocarbon-Based Gels in Oil Production Processes and Well Drilling
by Aleksey Telin, Lyubov Lenchenkova, Ravil Yakubov, Kira Poteshkina, Polina Krisanova, Andrey Filatov and Aleksandr Stefantsev
Gels 2023, 9(8), 609; https://doi.org/10.3390/gels9080609 - 28 Jul 2023
Cited by 3 | Viewed by 2100
Abstract
The use of gels in oil production processes has become a regular practice in oilfield operations and is constantly developing in all oil-producing countries of the world, as evidenced by the growth of publications and patent activity on this topic. Many oil production [...] Read more.
The use of gels in oil production processes has become a regular practice in oilfield operations and is constantly developing in all oil-producing countries of the world, as evidenced by the growth of publications and patent activity on this topic. Many oil production processes, such as hydraulic fracturing, conformance control, water, and gas shutoff, cannot be imagined without the use of gel technologies. Inorganic, organic, and hybrid gels are used, as well as foams, gel-forming, and gel-dispersed systems. The possibility of a broad control of structural and mechanical properties, thermal stability, and shear resistance by introducing microscale and nanoscale additives made hydrogels and hydrocarbon-based gels indispensable tools for oil engineers. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

23 pages, 6859 KiB  
Review
Application and Research Prospect of Functional Polymer Gels in Oil and Gas Drilling and Development Engineering
by Yingrui Bai, Yuan Liu, Keqing Yang and Youming Lang
Gels 2023, 9(5), 413; https://doi.org/10.3390/gels9050413 - 16 May 2023
Cited by 4 | Viewed by 1474
Abstract
Polymer gel materials are formed by physically crosslinking and chemically crosslinking to form a gel network system with high mechanical properties and reversible performance. Due to their excellent mechanical properties and intelligence, polymer gel materials are widely used in biomedical, tissue engineering, artificial [...] Read more.
Polymer gel materials are formed by physically crosslinking and chemically crosslinking to form a gel network system with high mechanical properties and reversible performance. Due to their excellent mechanical properties and intelligence, polymer gel materials are widely used in biomedical, tissue engineering, artificial intelligence, firefighting and other fields. Given the current research status of polymer gels at home and abroad and the current application status of oilfield drilling, this paper reviews the mechanism of polymer gels formed by physically crosslinking and chemically crosslinking, summarizes the performance characteristics and the mechanism of action of polymer gels formed by non-covalent bonding, such as hydrophobic bonding, hydrogen bonding, electrostatic and Van der Waals interactions interactions, and covalent bonding such as imine bonding, acylhydrazone bonding and Diels-Alder reaction. The current status and outlook of the application of polymer gels in drilling fluids, fracturing fluids and enhanced oil recovery are also introduced. We expand the application fields of polymer gel materials and promote the development of polymer gel materials in a more intelligent direction. Full article
(This article belongs to the Special Issue Gels for Oil Drilling and Enhanced Recovery (2nd Edition))
Show Figures

Figure 1

Back to TopTop