The Thermal Gelation Behavior and Performance Evaluation of High Molecular Weight Nonionic Polyacrylamide and Polyethyleneimine Mixtures for Indepth Water Control in Mature Oilfields

A delayed crosslinked polymer gel was developed for indepth water control in mature oilfields. The thermal gelation behavior of nonionic polyacrylamide (NPAM) and PEI was investigated, and sodium citrate (NaCit) was selected as a new retarder to prolong the gelation time. The gelation performance of NPAM/PEI gel system can be adjusted by the variation of NPAM or PEI concentration, and a quadratic model was developed by statistical analysis, which predict the gelation time of NPAM/PEI gel system. The obtained model showed high significance and good reliability as suggested by the F-ratio of 175.16 and high adjusted R-square value (0.9732). The decrease of the initial pH value of gelling solution leads to the weaker gel viscosity and longer gelation time due to the protonation of amine groups on the PEI chains. Increasing temperature resulted in higher gel viscosity but shorter gelation time. The addition of NaCit showed a good delayed gelation effect on the NPAM/PEI gel system, and the gel system in the presence of NaCit exhibited a good compatibility with injected and formation water. A dense three-dimensional structure was observed in matured NPAM/PEI/NaCit gel, and it could keep stable below 150℃. The gel system could effectively reduce the permeability (>95%) and restricted the flow of water after matured in natural cores.

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The Thermal Gelation Behavior and Performance Evaluation of High Molecular Weight Nonionic Polyacrylamide and Polyethyleneimine Mixtures for In-Depth Water Control in Mature Oilfields

Materials ◽

10.3390/ma13184142 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4142

Author(s):

Yi Qin ◽

Ruiquan Liao ◽

Shunshe Luo ◽

Junliang Li

Keyword(s):

Ph Value ◽

Gelation Time ◽

Quadratic Model ◽

Dimensional Structure ◽

Polymer Gel ◽

Water Control ◽

Thermal Gelation ◽

Gelation Behavior ◽

Depth Water ◽

Gel System

A delayed crosslinked polymer gel was developed for in-depth water control in mature oilfields. The thermal gelation behavior of nonionic polyacrylamide (NPAM) and PEI was investigated, and sodium citrate (NaCit) was selected as a new retarder to prolong the gelation time. The gelation performance of NPAM/PEI gel system can be adjusted by varying NPAM or PEI concentration, and a quadratic model is developed by statistical analysis, which predicts the gelation time of NPAM/PEI gel system. The obtained model shows high significance and good reliability, as suggested by the F-ratio of 175.16 and high adjusted R-square value (0.9732). The addition of NaCit exhibits a good delayed gelation effect on the NPAM/PEI gel system, better than that of NaCl. The decrease of the initial pH value of the gelling solution leads to the weaker gel viscosity and longer gelation time due to the protonation of amine groups on the PEI chains. Increasing temperature results in higher gel viscosity but shorter gelation time. The gel system in the presence of NaCit exhibits good compatibility with injection and formation water. A dense three-dimensional structure was observed in matured NPAM/PEI/NaCit gel, and it could keep stable below 160 °C. The gel system could effectively reduce the permeability (>95%) and restricted the flow of water after matured in natural cores.

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Delayed Crosslinking Amphiphilic Polymer Gel System with Adjustable Gelation Time Based on Competitive Inclusion Method

Polymers ◽

10.3390/polym11020381 ◽

2019 ◽

Vol 11 (2) ◽

pp. 381 ◽

Cited By ~ 4

Author(s):

Bin Xu ◽

Huiming Zhang ◽

He Bian

Keyword(s):

Gelation Time ◽

Salt Resistance ◽

Amphiphilic Polymer ◽

Polymer Gel ◽

Polymer Backbone ◽

Temperature Resistance ◽

Inclusion Method ◽

Profile Control ◽

Resistance Performance ◽

Gel System

Delayed crosslinking polymer gel systems are widely utilized in deep profile control processes for water production control in oilfields. In this paper, a kind of delayed crosslinking amphiphilic polymer gel system with adjustable gelation time based on competitive inclusion was prepared and its delayed crosslinking gelling properties were studied. The amphiphilic polymer of P(acrylamide (AM)–sodium acrylate (NaA)–N-dodecylacrylamide (DDAM)) was synthesized and it showed much better salt resistance, temperature resistance, and shear resistance performance compared with hydrolyzed polyacrylamide (HPAM). Phenol can be controlled released from the the cavity of β-cyclodextrin (β-CD) ring in the presence of the hydrophobic group used as the competitive inclusion agent in the amphiphilic polymer backbone. Accordingly, the gelation time of the delayed crosslinking amphiphilic polymer gel system is closely related to release rate of the crosslinker from the the cavity of β-CD ring. This study screened an amphiphilic polymer with good salt resistance and temperature resistance performance, which can be used in high temperature and high salinity reservoirs, and provided a feasible way to control the gelation time of the polymer gel system by the competitive inclusion method.

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A Novel Branched Polymer Gel System with Delayed Gelation Property for Conformance Control

SPE Journal ◽

10.2118/206742-pa ◽

2021 ◽

pp. 1-11

Author(s):

Tao Song ◽

Qi Feng ◽

Thomas Schuman ◽

Jie Cao ◽

Baojun Bai

Keyword(s):

Gelation Time ◽

Polymer Gels ◽

Environmental Concerns ◽

Water Production ◽

Polymer Gel ◽

Conformance Control ◽

Branched Polymer ◽

Chelating Ability ◽

Hydrolyzed Polyacrylamide ◽

Gel System

Summary Excessive water production from oil reservoirs not only affects the economical production of oil, but it also results in serious environmental concerns. Polymer gels have been widely applied to decrease water production and thus improve oil production. However, traditional polymer gels such as partially hydrolyzed polyacrylamide (HPAM)/chromium (III) gel systems usually have a short gelation time and cannot meet the requirement of some conformance control projects. This paper introduces a novel polymer gel system of which crosslinking time can be significantly delayed. A branched polymer grafted from arginine by the surface initiation method is synthesized as the backbone, chromium acetate is used as the crosslinker, and no additional additives are used for the gel system. The results show that the gelation time of this system can be delayed to 61 days at 45°C and 20 days at 65°C because of the rigid structure of the branched polymer and the excellent chromium (III) chelating ability of arginine. The polymer gels have been stable for more than 150 days at 45 and 65°C. Coreflooding and rheology tests have demonstrated that this branched polymer has good injectivity and shear resistance in high-permeabilityrocks.

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An Optimization Study of Polyacrylamide-Polyethylenimine-Based Polymer Gel for High Temperature Reservoir Conformance Control

International Journal of Polymer Science ◽

10.1155/2018/2510132 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Zulhelmi Amir ◽

Ismail Mohd Saaid ◽

Badrul Mohamed Jan

Keyword(s):

High Temperature ◽

Raw Materials ◽

Gelation Time ◽

Quadratic Equation ◽

Quadratic Model ◽

Polymer Gel ◽

Performance Information ◽

Conformance Control ◽

Crosslinked Polymer ◽

Optimization Study

This paper presents optimization formulation of organically crosslinked polymer gel for high temperature reservoir conformance control using response surface methodology (RSM). It is always desirable to approach an optimal polymer gel formulation study with adequate performance information related to viscosity and gelation time to minimize excessive water production. In this paper, the effects of polymer and crosslinker concentrations and their influences on gelation time and viscosity were investigated. Central composite design (CCD) was used to determine the optimized organically crosslinked polymer gel formulation. Concentrations of two main raw materials, namely, polyacrylamide (PAM) and polyethylenimine (PEI), were varied in a suitable range. This was to obtain the formulation with the desirable two vital responses, which are viscosity and gelation time. It was found that the results fitted the quadratic equation. Statistically, the quadratic model is reliable and adequate perfectly the variability of the responses obtained from the experimental data. In addition, gelation time and gel viscosity may be controlled by adjusting both polymer and crosslinker concentrations. The optimum formulated organically crosslinked polymer gel with significant desirability factor conditions was achieved at 1.5% w/v of PAM and 0.3% v/v of PEI.

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Dynamic and static gelation behavior of phenol formaldehyde resin gel system in ampoule bottles and porous media

Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles ◽

10.2516/ogst/2020055 ◽

2020 ◽

Vol 75 ◽

pp. 55

Author(s):

Haiyang Yu ◽

Wenjuan Ji ◽

Jiapeng Zheng

Keyword(s):

Porous Media ◽

Phenol Formaldehyde ◽

Gelation Time ◽

Quantitative Relationship ◽

Phenol Formaldehyde Resin ◽

Formaldehyde Resin ◽

Polymer Gel ◽

Gel Treatment ◽

Key Factor ◽

Gelation Behavior

The dynamic and static gelation process in porous media of the phenol formaldehyde resin gel was studied for successful application in conformance control and water shutoff. Shear rate was the most important factor affecting the dynamic gelation in porous media. Compare to static gelation in ampoule bottles and in porous media, the dynamic gelation time in porous media was extended by 2–6 times. The ability of migration and plugging after dynamic gelation was controlled by system concentration. The porous media permeability was the key factor for dynamic gelling time and strength. The quantitative relationship equation was established between dynamic gelling strength and permeability to choose the appropriate permeability for polymer gel treatment.

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Modeling of Partially Hydrolyzed Polyacrylamide-Hexamine-Hydroquinone Gel System Used for Profile Modification Jobs in the Oil Field

Journal of Petroleum Engineering ◽

10.1155/2013/709248 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Upendra Singh Yadav ◽

Vikas Mahto

Keyword(s):

Gelation Time ◽

Temperature Stability ◽

Oil Field ◽

Polymer Gel ◽

High Temperature Stability ◽

Injection Wells ◽

Profile Modification ◽

Partially Hydrolyzed Polyacrylamide ◽

Hydrolyzed Polyacrylamide ◽

Gel System

The cross-linked polymer gel systems are being used increasingly to redirect or modify reservoir fluid movement in the vicinity of injection wells for the purpose of permeability/profile modification job in the oil field due to their high temperature stability and capability to provide rigid gel having high mechanical strength. In this study, a partially hydrolyzed polyacrylamide-hexamine-hydroquinonegel is used for the development of polymer gel system. The experimental investigation demonstrates that the gelation time varies with polymer and crosslinker concentration and the temperature. The mathematical model is developed with the help of gelation kinetics of polymer gel and using Arrhenius equation, which relates the gelation time with polymer, crosslinker concentrations, and temperature. The developed model is solved with the help of multivariate regression method. It is observed in this study that the theoretical values of gelation time have good agreement with the experimental values.

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Gelation Behavior of Polyacrylamide Reinforced with Nano-Silica for Water Shutoff Treatment in Oil Field

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.307.252 ◽

2020 ◽

Vol 307 ◽

pp. 252-257

Author(s):

Nurhazwane Abdul Fadil ◽

Sonny Irawan ◽

Nur Amelia Mohd Isa ◽

Siti Rohaida Shafian

Keyword(s):

Gelation Time ◽

Silica Content ◽

Oil Field ◽

Nano Silica ◽

Water Shutoff ◽

Silica Concentration ◽

Gelation Behavior ◽

Hydrolyzed Polyacrylamide ◽

Placement Depth ◽

Gel System

Polyacrylamide gel system is widely been used in oilfield for water shutoff treatment. Gelation behavior such as proper gelation time provides a basic guideline on gel placement depth in reservoir layers. In this study, the gelation behavior of partially hydrolyzed polyacrylamide crosslinked with chromium(III) acetate (PHPA/Cr3+) reinforced with nano-silica was studied in term of gelation time and gel stability. The gelation time of PHPA/Cr3+ gel could be controlled with the addition of nano-silica where the gel has shown a delay in gelation time at low concentration of nano-silica. At 0.3 wt.% of nano-silica concentration, the gelation time has shown two times delay compared to the original gel system. The gel at the formulations of 0.7 wt.% and 1.0 wt.% nano-silica content remained stable with H code after 24 hours observation.

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Gelation Performance and Microstructure Study of Chromium Gel and Phenolic Resin Gel in Bulk and Porous Media

Journal of Energy Resources Technology ◽

10.1115/1.4027570 ◽

2014 ◽

Vol 136 (4) ◽

Cited By ~ 9

Author(s):

Jian Zhang ◽

Hong He ◽

Yefei Wang ◽

Xiaoli Xu ◽

Yuejun Zhu ◽

...

Keyword(s):

Porous Media ◽

Phenolic Resin ◽

Cluster Structure ◽

Gelation Time ◽

Polymer Gel ◽

3D Network ◽

Shape Structure ◽

Gelation Behavior ◽

Gel Membranes ◽

Off Time

Polymer gel has been widely used to control excessive water production in many mature oilfields; however, there still exist some problems concerning the differences between gelation behavior in bulk and porous media. In this paper, the gelation time and microstructures of chromium gel and phenolic resin gel in bulk and porous media were studied. Results showed that for chromium gel, the initial gelation time in porous media was about 2.5–3.5 times of that in bulk and final gelation time in porous media was about 6.0–7.0 times of that in bulk. While for phenolic resin gel, the initial gelation time in porous media was about 1.0–1.5 times of that in bulk, and final gelation time in porous media was about 1.5–2.0 times of that in bulk. The morphology of chromium gel and phenolic resin gel in bulk were dendritic shape structure and 3D network structure, respectively. However, the morphology of chromium gel and phenolic resin gel in porous media were both dense gel membranes at low magnification. While at higher magnification, compared with the branchlike cluster structure of chromium gel in porous media, the network of phenolic resin gel was more developed. The experimental results can provide the basis for determining well shut off time and reveal the differences of gel microstructures between the chromium gel and phenolic gel in bulk and porous media.

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