Intelligent release self-assembly bridging particle adjusting and plugging system with high plugging performance
By using an intelligent release self-assembly bridging particle plugging system, the self-assembly particles and suspending agents are used to form bridging plugs in the reservoir, which solves the problems of reservoir damage and low recovery rate of traditional plugging agents and achieves efficient and selective plugging effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHONGQING UNIVERSITY OF SCIENCE AND TECHNOLOGY
- Filing Date
- 2025-12-03
- Publication Date
- 2026-04-14
AI Technical Summary
Traditional inorganic particulate plugging agents lack selectivity in oil reservoir sealing, easily causing irreversible damage to the reservoir. Furthermore, long-term water and gas flooding leads to the formation of fractures and high-permeability channeling in the reservoir, resulting in low recovery rates.
A smart release self-assembly bridging particle plugging system is adopted, which includes self-assembly particles and a suspending agent. The suspending agent carries the self-assembly particles to the target location to self-assemble and form a bridging plug. The injection rate, volume, concentration and suspending agent concentration are optimized to improve the plugging performance.
It achieves efficient and selective plugging in oil reservoirs, reduces reservoir damage, and improves recovery rate. It is suitable for formations with a permeability of 10000×10-3μm2.
Smart Images
Figure CN121852018A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of oil and gas field enhanced oil recovery technology, specifically to an intelligent release self-assembly bridging particle plugging system with high plugging performance. Background Technology
[0002] Given the widespread distribution and low cost of water resources, as well as their significant production-enhancing effects in oil reservoir development, waterflooding technology has been widely adopted.
[0003] Meanwhile, gas-driven technology utilizes the physical and chemical properties of gases to improve reservoir fluid flow and further enhance oil recovery, attracting increasing attention in recent years. However, long-term water-drive and gas-drive operations have led to the formation of numerous fractures and high-permeability channeling pathways in the reservoir, resulting in ineffective water / gas circulation and low recovery rates. In practical development, to avoid problems such as high-temperature oxidative degradation, shear degradation, and short sealing time of plugging agents under reservoir conditions, inorganic particle-based modulating displacement technology is typically employed.
[0004] Traditional inorganic particulate plugging agents have advantages such as high stability, high plugging strength, wide availability and low price, but their prominent drawback is that the plugging is not selective and can easily cause irreversible damage to the entire reservoir, "blocking" the reservoir.
[0005] Therefore, in order to improve the poor development results caused by water / gas channeling in low-permeability and ultra-low-permeability reservoirs, a new solution is needed to address the above problems. Summary of the Invention
[0006] The purpose of this invention is to provide an intelligent release self-assembly bridging particle plugging system with high plugging performance to solve the technical problems mentioned in the background art.
[0007] To achieve the above objectives, the present invention provides the following technical solution: a smart release self-assembly bridging particle plugging system with high plugging performance, comprising smart release self-assembly particles and a suspending agent;
[0008] The suspending agent is used to carry the self-assembled particles into the formation, and the self-assembled particles can self-assemble at the target location to form a bridging seal.
[0009] The optimal application parameters for the plugging system are: injection rate 1.5 ml / min, injection volume 1.25 PV, self-assembled particle concentration 4%–6%, and suspending agent concentration 0.15%–0.25%.
[0010] Furthermore, the suspending agent is a polymer solution or a guar gum solution.
[0011] Furthermore, the mass concentration of the polymer solution is 0.2%.
[0012] Furthermore, the mass concentration of the guar gum solution is 0.4%.
[0013] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembled particle plugging system was investigated at different injection rates (0.5ml / min, 1.0ml / min, 1.5ml / min, 2.0ml / min, 2.5ml / min, 3.0ml / min).
[0014] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembly particle plugging system under different injection volumes (0.5PV, 0.75PV, 1.0PV, 1.25PV, 1.5PV) was investigated.
[0015] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembled particle plugging system with different self-assembled particle concentrations (0%, 2%, 4%, 6%) was investigated.
[0016] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembly particle plugging system was investigated at different suspending agent concentrations (0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, 0.40%).
[0017] Using a sand tube model, the plugging performance of the intelligent release self-assembly particle plugging system under different permeabilities (5000, 10000, 15000, 20000, 25000, 30000×10-3μm2) was investigated.
[0018] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the smart release self-assembly particle plugging system under different types of suspending agents (3% starch, 0.4% guar gum, 0.2% polymer) was investigated.
[0019] Compared with the prior art, the beneficial effects of the present invention are:
[0020] The optimal injection rate of the self-assembled particle plugging system selected through dynamic plugging experiments is 1.5 ml / min, the optimal injection volume is 1.25 PV, the optimal particle concentration is 4%–6%, and the optimal suspending agent concentration is 0.15%–0.25%. Using the above parameters, reservoir permeability adaptability studies were conducted. The experimental results show that the permeability suitable for self-assembled particles is around 10000×10-3 μm2. At this point, the diameter of the sand tube pore throat and the particle size of the self-assembled particles form an optimal match. Under the "dragging" effect of the suspending agent, the self-assembled particles are transported into the sand tube, forming an effective and stable plug. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a flowchart of the sealing performance test of the present invention;
[0023] Figure 2 The figures show the plugging rate statistics at different injection rates and the physical simulation curves of the pressure gradient versus injection rate after plugging, as presented in this invention.
[0024] Figure 3 The figures show the plugging rate statistics and the physical simulation curves of pressure gradient versus injection volume after plugging under different injection volumes according to the present invention.
[0025] Figure 4 The figures show the plugging rate statistics for different particle concentrations and the physical simulation curves of pressure gradient versus particle concentration after plugging, as presented in this invention.
[0026] Figure 5 The figures show the plugging rate statistics for different suspending agent concentrations and the physical simulation curves of pressure gradient versus suspending agent concentration after plugging, as presented in this invention.
[0027] Figure 6 The figures show the plugging rate statistics under different permeabilities and the pressure gradient versus permeability physical simulation curve after plugging, as presented in this invention.
[0028] Figure 7 The diagram shows the blockage rate statistics under different injection methods of the present invention, and the pressure gradient after blockage versus the physical simulation curve of the injection method. Detailed Implementation
[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0030] This invention, through indoor experimental research, determines the effectiveness of intelligent release self-assembly bridging particle plugging technology in deep well plugging, identifies the technical limits of specific applications, provides relevant basis for well selection of this technology, and further improves the application effect of deep well plugging technology.
[0031] Using a sand-filled pipe model, the plugging effect of the granular system was evaluated. The effects of factors such as injection method, injection rate, injection volume, permeability, particle concentration, and suspension system concentration on the plugging effect and deep migration performance of the granular system were investigated. The optimal scheme for applying particles to the sand-filled pipe model with the best plugging effect was selected.
[0032] Specifically as follows:
[0033] Example 1:
[0034] A smart release self-assembly bridging particle plugging system with high plugging performance includes smart release self-assembly particles and a suspending agent;
[0035] The suspending agent is used to carry self-assembly particles into the formation, and the self-assembly particles can self-assemble at the target location to form a bridging seal.
[0036] The optimal application parameters for the plugging system are: injection rate 1.5 ml / min, injection volume 1.25 PV, self-assembled particle concentration 4%–6%, and suspending agent concentration 0.15%–0.25%.
[0037] The suspending agent is a polymer solution or a guar gum solution.
[0038] The polymer solution has a mass concentration of 0.2%.
[0039] Example 2:
[0040] Based on the above embodiment 1, a method for regulating blockage in oil and gas fields is further proposed;
[0041] The plugging system is suitable for formations with a permeability of approximately 10,000 × 10⁻³ μm².
[0042] The system comprises 4%–6% self-assembled particles and 0.15%–0.25% suspending agent for clogging control;
[0043] The aforementioned plugging system was injected at a rate of 1.5 ml / min into a formation with a permeability of approximately 10000 × 10⁻³ μm², with a permeability of 1.25 PV.
[0044] The suspending agent is a polymer solution with a mass concentration of 0.2% or a guar gum solution with a mass concentration of 0.4%.
[0045] Example 3:
[0046] See Figure 1 Based on the above embodiments one and two, the following specific detection applications are proposed:
[0047] Preferred injection speed
[0048] Injection rate has a certain impact on the plugging performance of the intelligent release self-assembly particle plugging system. As the injection rate increases, the particles can migrate to a greater distance.
[0049] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembled particle plugging system was investigated at different injection rates (0.5ml / min, 1.0ml / min, 1.5ml / min, 2.0ml / min, 2.5ml / min, 3.0ml / min).
[0050] Results: Subsequent water flooding curves showed that a 1.5 ml / min injection rate of the plugging agent resulted in better particle migration and adhesion, and the water flooding curve quickly reached a plateau. With increasing injection rate, the plugging efficiency of the particulate plugging agent system increased, then decreased. At an injection rate of 1.5 ml / min, the plugging efficiency reached 97.82%. Therefore, 1.5 ml / min is selected as the optimal injection rate for the particulate system. (See reference...) Figure 2 .
[0051] Preferred injection volume
[0052] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembly particle plugging system under different injection volumes (0.5PV, 0.75PV, 1.0PV, 1.25PV, 1.5PV) was investigated.
[0053] Results: The plugging capability of the self-assembled particle plugging system increases with increasing injection volume. At an injection volume of 0.5 PV, the plugging rate of the particle plugging agent was 73.27%; at 0.75 PV, the plugging rate was 84.33%; at 1 PV (particle volume accounting for more than 5% of pore volume), the plugging rate reached over 90%; at 1.25 PV, the plugging rate was 96.61%; and when the injection volume increased to 1.5 PV, the plugging rate rose to 97.78%. With increasing injection volume, the plugging rate of the particle plugging agent system showed a trend of first rapidly increasing and then slowly increasing. When the particle plugging agent was injected at a volume of 1.25 PV, the plugging rate of the particle plugging agent system changed from a relatively rapid increase to a slow increase; therefore, 1.25 PV was selected as the optimal injection volume for the particle system. (See also...) Figure 3 .
[0054] Preferred particle concentration
[0055] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembled particle plugging system with different self-assembled particle concentrations (0%, 2%, 4%, 6%) was investigated.
[0056] Results: Dynamic experiments in the blank control group (without particles) showed that the polymer suspension had almost no blocking effect. Evaluation experiments on the blocking effect with particles showed that the higher the particle concentration, the higher the blocking rate of the particle plugging system. This is because high particle concentrations increase the number of adhesive assemblies between particles, achieving stable adhesive bridging and blocking capabilities. When the particle concentration reached 4%, the blocking rate was consistently above 90%. Therefore, a particle concentration of 4%–6% was ultimately selected for the intelligent release self-assembly particle system. (See also...) Figure 4 .
[0057] Example 4:
[0058] Preferred suspending agent concentration
[0059] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of the intelligent release self-assembly particle plugging system was investigated at different suspending agent concentrations (0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, 0.40%).
[0060] Results: The plugging rate increased with increasing suspending agent concentration. However, both excessively high and low polymer concentrations negatively impacted the plugging effect of the particle system. The former affected the adhesion between particles, while the latter resulted in low viscosity of the suspension system, which failed to provide sufficient "dragging and carrying" effect on the self-assembled particles during injection. When the polymer concentration was above 0.15%, sufficient "dragging and carrying" effect was achieved on the self-assembled particles, allowing them to penetrate deeper into the sand pipe, with plugging rates exceeding 90%. However, at a concentration of 0.25%, the excessive polymer began to negatively affect the probability of particle collision and adhesion. Considering economic costs, the optimal concentration for intelligent release of self-assembled bridging particles was ultimately 0.15%–0.25%.
[0061] Analysis of the plugging pressure gradient and plugging pressure under different suspending agent concentrations showed that polymer concentration had little effect on the plugging effect of particulate plugging agents. (See also...) Figure 5 .
[0062] Optimal penetration rate
[0063] Using a sand tube model, the plugging performance of the intelligent release self-assembly particle plugging system under different permeabilities (5000, 10000, 15000, 20000, 25000, 30000×10-3μm2) was investigated.
[0064] Results: When the permeability was around 10000×10⁻³ μm², the sand pipe plugging rate reached 97.87%, and the plugging pressure gradient reached 140.31 kPa / m. Self-assembled particles showed the best plugging effect. (See also...) Figure 6 .
[0065] Preferred injection method
[0066] Using a sand tube model (permeability 10000×10-3μm2), the plugging performance of a smart release self-assembly particle plugging system under different types of suspending agents (3% starch, 0.4% guar gum, 0.2% polymer) was investigated.
[0067] Results: Using guar gum or polymer solution as the particulate suspending agent resulted in better blocking performance than using starch as the particulate suspending agent. (See also...) Figure 7 .
[0068] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
Claims
1. A smart release self-assembly bridging particle plugging system with high plugging performance, characterized in that: Includes smart-release self-assembling particles and suspending agents; The suspending agent is used to carry the self-assembled particles into the formation, and the self-assembled particles can self-assemble at the target location to form a bridging seal. The optimal application parameters for the plugging system are: injection rate 1.5 ml / min, injection volume 1.25 PV, self-assembled particle concentration 4%–6%, and suspending agent concentration 0.15%–0.25%.
2. The intelligent release self-assembly bridging particle plugging system with high plugging performance according to claim 1, characterized in that: The suspending agent is a polymer solution or a guar gum solution.
3. The intelligent release self-assembly bridging particle plugging system with high plugging performance according to claim 1, characterized in that: The polymer solution has a mass concentration of 0.2%.
4. The intelligent release self-assembly bridging particle plugging system with high plugging performance according to claim 1, characterized in that: The mass concentration of the guar gum solution is 0.4%.