Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid
Deep wells and ultra-deep wells often encounter cracks, karst caves, and other developed strata, which can lead to leakage during drilling. Conventional bridge slurry plugging technology is prone to leaking due to the poor plugging effect of the plugging agent. The gel plugging agent possesses chara...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-02-01
|
| Series: | Gels |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2310-2861/10/2/112 |
| _version_ | 1827343532426264576 |
|---|---|
| author | Quanyang Wang Chenghua Zhou Honghu Zhang Xue Zhang Xinxin Wen Jiexin Bai Hui Mao |
| author_facet | Quanyang Wang Chenghua Zhou Honghu Zhang Xue Zhang Xinxin Wen Jiexin Bai Hui Mao |
| author_sort | Quanyang Wang |
| collection | DOAJ |
| description | Deep wells and ultra-deep wells often encounter cracks, karst caves, and other developed strata, which can lead to leakage during drilling. Conventional bridge slurry plugging technology is prone to leaking due to the poor plugging effect of the plugging agent. The gel plugging agent possesses characteristics of flexible plugging and adaptive matching of formation leakage channels. It can fill cracks or caves and enhance the pressure-bearing capacity of the formation. A controllable crosslinking plugging agent based on low-molecular-weight polyacrylamide was studied. Polyacrylamide with different molecular weights is synthesized from acrylamide and an initiator. A crosslinking time-controllable polymer is synthesized from low-molecular-weight polyacrylamide by adding crosslinking agent and retarder. The low-molecular-weight polyacrylamide plugging agent has low viscosity before gelation and good fluidity in the wellbore. After being configured on the ground, it is transported by pipeline and sent underground to reach the thickening condition. The gel solution rapidly solidifies, and its strength improves after high-temperature crosslinking. The synthesis conditions of the polymer were as follows: a monomer concentration of 9%, initiator 3.5%, synthesis temperature of 65 °C, and hydrogen peroxide initiator. The optimal formula of the gel plugging agent is as follows: a polymer concentration of 6%, a crosslinking agent concentration of 1%, and a retarder concentration of 8%. The generated polymer molecular structure contains amide groups. This crosslinking time-controllable plugging agent based on low-molecular-weight polyacrylamide has stable rheology, and its temperature resistance can reach 150 °C. At 150 °C, the gelation time can be controlled by adjusting the concentration of retarder, and the longest can reach 4 h. The plugging efficiency of the gel plugging agent is more than 95%. With the increase in seam width, the pressure of the gel plugging agent gradually decreases. |
| first_indexed | 2024-03-07T22:31:42Z |
| format | Article |
| id | doaj.art-7b11dc1ce9304e859072807535a50d16 |
| institution | Directory Open Access Journal |
| issn | 2310-2861 |
| language | English |
| last_indexed | 2024-03-07T22:31:42Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Gels |
| spelling | doaj.art-7b11dc1ce9304e859072807535a50d162024-02-23T15:17:29ZengMDPI AGGels2310-28612024-02-0110211210.3390/gels10020112Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling FluidQuanyang Wang0Chenghua Zhou1Honghu Zhang2Xue Zhang3Xinxin Wen4Jiexin Bai5Hui Mao6Drilling Engineering Research Institute, Sinopec Xinan Oilfield Service Corporation, Deyang 618000, ChinaDrilling Engineering Research Institute, Sinopec Xinan Oilfield Service Corporation, Deyang 618000, ChinaDrilling Engineering Research Institute, Sinopec Xinan Oilfield Service Corporation, Deyang 618000, ChinaDrilling Engineering Research Institute, Sinopec Xinan Oilfield Service Corporation, Deyang 618000, ChinaCollege of Energy Resources, Chengdu University of Technology, Chengdu 610059, ChinaCollege of Energy Resources, Chengdu University of Technology, Chengdu 610059, ChinaCollege of Energy Resources, Chengdu University of Technology, Chengdu 610059, ChinaDeep wells and ultra-deep wells often encounter cracks, karst caves, and other developed strata, which can lead to leakage during drilling. Conventional bridge slurry plugging technology is prone to leaking due to the poor plugging effect of the plugging agent. The gel plugging agent possesses characteristics of flexible plugging and adaptive matching of formation leakage channels. It can fill cracks or caves and enhance the pressure-bearing capacity of the formation. A controllable crosslinking plugging agent based on low-molecular-weight polyacrylamide was studied. Polyacrylamide with different molecular weights is synthesized from acrylamide and an initiator. A crosslinking time-controllable polymer is synthesized from low-molecular-weight polyacrylamide by adding crosslinking agent and retarder. The low-molecular-weight polyacrylamide plugging agent has low viscosity before gelation and good fluidity in the wellbore. After being configured on the ground, it is transported by pipeline and sent underground to reach the thickening condition. The gel solution rapidly solidifies, and its strength improves after high-temperature crosslinking. The synthesis conditions of the polymer were as follows: a monomer concentration of 9%, initiator 3.5%, synthesis temperature of 65 °C, and hydrogen peroxide initiator. The optimal formula of the gel plugging agent is as follows: a polymer concentration of 6%, a crosslinking agent concentration of 1%, and a retarder concentration of 8%. The generated polymer molecular structure contains amide groups. This crosslinking time-controllable plugging agent based on low-molecular-weight polyacrylamide has stable rheology, and its temperature resistance can reach 150 °C. At 150 °C, the gelation time can be controlled by adjusting the concentration of retarder, and the longest can reach 4 h. The plugging efficiency of the gel plugging agent is more than 95%. With the increase in seam width, the pressure of the gel plugging agent gradually decreases.https://www.mdpi.com/2310-2861/10/2/112delayed crosslinkinglow viscosityplugging materialpolymer gelwell leakage |
| spellingShingle | Quanyang Wang Chenghua Zhou Honghu Zhang Xue Zhang Xinxin Wen Jiexin Bai Hui Mao Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid Gels delayed crosslinking low viscosity plugging material polymer gel well leakage |
| title | Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid |
| title_full | Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid |
| title_fullStr | Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid |
| title_full_unstemmed | Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid |
| title_short | Preparation of Low-Molecular-Weight Polyacrylamide as the Delayed Crosslinking Plugging Agent for Drilling Fluid |
| title_sort | preparation of low molecular weight polyacrylamide as the delayed crosslinking plugging agent for drilling fluid |
| topic | delayed crosslinking low viscosity plugging material polymer gel well leakage |
| url | https://www.mdpi.com/2310-2861/10/2/112 |
| work_keys_str_mv | AT quanyangwang preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT chenghuazhou preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT honghuzhang preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT xuezhang preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT xinxinwen preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT jiexinbai preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid AT huimao preparationoflowmolecularweightpolyacrylamideasthedelayedcrosslinkingpluggingagentfordrillingfluid |