CN108410439B - Method for increasing production of oil well by combining gel foam and in-situ microemulsion - Google Patents
Method for increasing production of oil well by combining gel foam and in-situ microemulsion Download PDFInfo
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Abstract
The invention discloses a method for increasing the yield of an oil well by combining gel foam and in-situ microemulsion. The present invention can greatly raise crude oil yield of oil well and can reduce water yield of oil well.
Description
Technical Field
The invention belongs to the technical field of oilfield development and oil well production increase, and particularly relates to a method for increasing the oil well production by combining gel foam and in-situ microemulsion.
Background
Oil well water production is a common problem in the development of oil fields. Due to the heterogeneity of the oil reservoir and the further aggravation of the heterogeneity caused by long-term water drive, the difference of fluid flow and other reasons (such as operation failure, wrong production measures and the like), hypertonic channels or large channels are gradually formed in the oil reservoir, a formation flow line field is fixed, water flow dominant channels are formed among oil wells, water cones, water channeling and water fingering are further caused, and therefore some oil wells are subjected to early water breakthrough or flooding, and water drive is inefficient or ineffective in circulation, and the development effect of the oil reservoir water drive is seriously influenced.
The water shutoff profile control technology is always an effective means for improving the water injection development effect and realizing the stable yield of an oil reservoir in an oil field, after the oil field enters a high-water-content or ultra-high-water-content exploitation period, the water flooding problem of the oil field is more and more complicated, and the water shutoff profile control and other water control and oil stabilization technical difficulties and requirements are more and more high. In the initial research and application stage of water shutoff and profile control technology in China, high-strength plugging agents are mainly used, and the plugging agent materials mainly comprise cement, resin, active thick oil, water glass/calcium chloride and the like. Then, the strong gel plugging agent is mainly used, the action mechanism is mostly physical barrier type plugging, and the purpose of adjusting the water absorption profile and the fluid production profile of the near-well stratum is achieved. In recent years, many new advances are made in the aspects of deep profile control (profile control) liquid flow diversion research and application, a plurality of deep profile control (profile control) technologies including weak gel, Colloidal Dispersion Gel (CDG), bulk expanded particles, flexible particles and the like are formed, particularly a recently developed nitrogen foam system is rapidly developed and applied due to the unique selective plugging effect (large plugging, small plugging, water plugging and oil plugging), and plays an important role in improving the development effect of a water flooding oil field and improving the recovery ratio.
However, the application of nitrogen foam systems (nitrogen foam, polymer-reinforced foam, gel-reinforced foam) still only expands swept volume, and cannot improve the oil-washing efficiency of water flooding, and the oil-increasing effect of treating oil wells is affected.
Disclosure of Invention
The invention provides a method for increasing the yield of an oil well by combining gel foam and in-situ microemulsion, which can greatly improve the crude oil yield of the oil well and reduce the water yield of the oil well.
In order to solve the technical problems, the invention adopts the following technical scheme:
a method for increasing oil well production by combining gel foam and in-situ microemulsion comprises the following steps:
(1) injecting a certain volume of nitrogen into the oil well to form a preposed nitrogen slug;
(2) injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (1) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the gel foaming agent in the gel foaming agent aqueous solution comprises the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent, wherein the mass percent of each component is the percentage of each component in the total mass of the gel foaming agent aqueous solution;
(3) injecting a mixed system of a certain volume of nitrogen and a polymer foaming agent aqueous solution into the oil well in the step (2) according to the volume ratio of the nitrogen to the polymer foaming agent aqueous solution of 1: 1-3: 1 to form a polymer nitrogen foam slug, wherein the polymer foaming agent in the polymer foaming agent aqueous solution comprises the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN-and 0.1 to 0.3 percent of polymer, wherein the mass percent of each component is the percentage of each component in the total mass of the polymer foaming agent aqueous solution;
(4) injecting a certain volume of in-situ microemulsion aqueous solution into the oil well in the step (3) to form an in-situ microemulsion slug, wherein the in-situ microemulsion in the in-situ microemulsion aqueous solution consists of the following components in percentage by mass: 60.5-4% of in-situ microemulsion surfactant SH and 0.1-0.3% of polymer, wherein the mass percent of each component is the percentage of each component in the total mass of the in-situ microemulsion aqueous solution;
(5) injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (4) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the gel foaming agent in the gel foaming agent aqueous solution comprises the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent, wherein the mass percent of each component is the percentage of each component in the total mass of the gel foaming agent aqueous solution.
Further, in step (1), the oil reservoir and development parameters of the oil well are as follows: the oil reservoir temperature is 50-100 ℃, the porosity is 15-35%, the permeability is 30-1500 md, the water content is more than 90%, and the extraction degree is less than 37%.
Further, in the step (1), the volume of the injected nitrogen gas is 100m3～300m3。
Further, in the step (2), the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3。
Further, in the step (3), the volume of the aqueous solution of the polymer foaming agent in the mixed system is 400m3～800m3。
Further, in the step (4), the volume of the in-situ microemulsion water solution is injected to be 500m3～1000m3。
Further, in the step (5), the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3。
Further, the total volume of the aqueous gel foam solution in step (2), the aqueous polymer foam solution in step (3), the aqueous in-situ microemulsion solution in step (4) and the aqueous gel foam solution in step (5) is 1500m3～3000m3。
Further, the foaming agent HN-1 is sodium fatty alcohol polyoxyethylene ether carboxylate; the polymer is a temperature-resistant and salt-resistant polymer ZL-II, the relative molecular mass of the polymer is 2400 ten thousand, and the hydrolysis degree of the polymer is 22%; the cross-linking agent is an organic phenolic cross-linking agent; the in-situ microemulsion surfactant SH6 is prepared by mixing polyether carboxylate/sulfonate anionic-nonionic surfactant and cationic surfactant, and the ratio of the polyether carboxylate/sulfonate anionic-nonionic surfactant to the cationic surfactant is 1: 0.5-1: 2; the water used in preparing the gel foaming agent aqueous solution, the polymer foaming agent aqueous solution and the in-situ microemulsion aqueous solution is oil field injection sewage.
Compared with the prior art, the invention has the beneficial effects that:
the function of the preposed nitrogen section plug in the step (1) is to seal a nitrogen pressure water cone and isolate formation water, the function of the gel nitrogen foam section plug in the step (2) is to seal a dominant channel, a high permeability layer and a water outlet channel, the function of the polymer nitrogen foam section plug in the step (3) is to increase the sealing radius, the function of the in-situ microemulsion section plug in the step (4) is to solubilize crude oil, strip an oil film and start residual oil, and further increase the yield of the crude oil greatly, the function of the gel nitrogen foam section plug in the step (5) is to seal a near-wellbore area, and the effective periods of the functions of the in-situ microemulsion section plug in the step (4), the polymer nitrogen foam section plug in the step (3) and the gel nitrogen foam section plug in the step (2) are protected. The gel nitrogen foam system has strong effect of plugging a high permeable layer and obvious effect of expanding swept volume, and the in-situ microemulsion system has ultralow interfacial tension and stronger crude oil solubilizing capability, so the in-situ microemulsion system has higher oil displacement efficiency.
Drawings
FIG. 1 is a graph of NP23-2308 well development dynamics before and after nitrogen foam and microemulsion treatment;
FIG. 2 shows the influence of different gas-liquid ratios on the resistance factor of a gel nitrogen foam system (the experimental temperature is 100 ℃, and the gas injection speed is 1 mL/min);
FIG. 3 shows the particle size distribution of phase microemulsion droplets in the in-situ microemulsion surfactant SH6 (SH6 concentration 3%, oil-water ratio 1: 1).
Detailed Description
The following examples further illustrate the present invention but are not to be construed as limiting the invention. Modifications or substitutions to methods, procedures, or conditions of the invention may be made without departing from the spirit and scope of the invention.
First, the combined application of gel nitrogen foam system and in-situ microemulsion system slug has the field effect
The side water and bottom water reservoir types of the Zhongpetroleum Jidongnanbao oil field are more, the reservoir heterogeneity is serious, and the side water immersion and the bottom water coning under the action of water channeling cause the water content of the oil well to be increased rapidly at the initial stage of natural energy opening of the oil field, thereby seriously affecting the development effect of the oil field. The oil reservoir and development parameters of the oil well are that the oil reservoir temperature is 50-100 ℃, the porosity is 15-35%, the permeability is 30-1500 md, the water content is more than 90%, and the extraction degree is less than 37%.
1. Injection slug structural design
The water content of the oil wells constructed on site is more than 90 percent, and the water content of a part of the oil wells is 100 percent. Therefore, the injection slug structure design firstly plugs the dominant channel to inhibit the immersion of edge water bottom water, and then plays the role of high oil displacement efficiency of the microemulsion system. The designed injection slug structure and injection amount are as follows:
(1) injecting 100m into oil well3～300m3Forming a front nitrogen slug;
(2) injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (1) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3Wherein the gel foaming agent in the gel foaming agent aqueous solution consists of the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent, wherein the mass percent of each component is the percentage of each component in the total mass of the gel foaming agent aqueous solution;
(3) injecting a mixed system of a certain volume of nitrogen and a polymer foaming agent aqueous solution into the oil well in the step (2) according to the volume ratio of the nitrogen to the polymer foaming agent aqueous solution of 1: 1-3: 1 to form a polymer nitrogen foam slug, wherein the volume of the polymer foaming agent aqueous solution in the mixed system is 400m3～800m3Wherein the polymer foaming agent in the polymer foaming agent aqueous solution consists of the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN-and 0.1 to 0.3 percent of polymer, wherein the mass percent of each component is the percentage of each component in the total mass of the polymer foaming agent aqueous solution;
(4) injecting 500m into the oil well in the step (3)3～1000m3The in-situ microemulsion slug is formed by the in-situ microemulsion aqueous solution, wherein the in-situ microemulsion in the in-situ microemulsion aqueous solution consists of the following components in percentage by mass: 60.5 to 4 percent of in-situ microemulsion surfactant SH and 0.1 to 0.3 percent of polymer, and each groupThe mass percentages of the components are the percentage of all the components in the total mass of the in-situ microemulsion water solution;
(5) injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (4) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3Wherein the gel foaming agent in the gel foaming agent aqueous solution consists of the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent, wherein the mass percent of each component is the percentage of each component in the total mass of the gel foaming agent aqueous solution.
Wherein the total volume of the gel foaming agent aqueous solution in the step (2), the polymer foaming agent aqueous solution in the step (3), the in-situ microemulsion aqueous solution in the step (4) and the gel foaming agent aqueous solution in the step (5) is 1500m3～3000m3。
Wherein the foaming agent HN-1 is sodium fatty alcohol polyoxyethylene ether carboxylate; the polymer is a temperature-resistant and salt-resistant polymer ZL-II, the relative molecular mass of the polymer is 2400 ten thousand, and the hydrolysis degree of the polymer is 22%; the cross-linking agent is an organic phenolic cross-linking agent; the in-situ microemulsion surfactant SH6 is prepared by mixing polyether carboxylate/sulfonate anionic-nonionic surfactant and cationic surfactant, and the ratio of the polyether carboxylate/sulfonate anionic-nonionic surfactant to the cationic surfactant is 1: 0.5-1: 2; the water used in preparing the gel foaming agent aqueous solution, the polymer foaming agent aqueous solution and the in-situ microemulsion aqueous solution is oil field injection sewage.
2. Effect of field application
(1) Effect of single well application
FIG. 1 is a dynamic curve of NP23-2308 well development before and after treatment of a nitrogen foam system and a microemulsion system, and it can be seen that a gel nitrogen foam system slug and an in-situ microemulsion system slug are alternately injected into an oil well, open flow is carried out after a period of well closing, the water content is reduced from 99.3% to 72.3%, the water content is reduced by 27 points, the daily oil production is increased from 0t/d to 8.5t/d, the accumulated oil increase is 485t, and the oil increase effect is obvious.
(2) Statistics of annual oil-increasing effect
The gel nitrogen foam system slug and the in-situ microemulsion system slug are alternately injected into a treatment oil well, 9 well times in 2015, 20 well times in 2016, 34 well times in 2017, 63 well times in total, and 23618t of cumulative oil increment. The specific application effect is as follows:
in 2015, gel nitrogen foam and the in-situ microemulsion are applied to the oil well for 9 wells, 8 mouths of the well are opened, the effect is 7 wells, and the effective rate is 87.5%; the water content is reduced from 96.7 percent to 78.2 percent by 18.5 percent; the daily oil production of a single well is increased to 4.40t/d from 0.33t/d, the daily oil production is increased to 4.07t/d, and the cumulative oil gain is 3056t (Table 1).
Table 12015 years old oil Jidongnanburg oil field gel nitrogen foam and in-situ microemulsion implementation effect statistics
In 2016, gel nitrogen foam and in-situ microemulsion are implemented on an oil well for 20 times, 17 effective times are achieved, and the effective rate is 85.0%; the average water content is reduced to 70.7 percent from 96.2 percent and is reduced by 25.5 percent; the average daily oil production of a single well is increased from 0.96t/d to 5.36t/d, the daily oil production is increased by 4.4t/d, and the cumulative oil increase 10404t (Table 2).
TABLE 22016 years old oil Jidongnanbao oilfield gel nitrogen foam and in-situ microemulsion implementation effect statistics
In 2017, gel nitrogen foam and in-situ microemulsion are applied to the oil well for 30 well times, the effective number is 26 well times, and the effective rate is 86.7%; the average water content is reduced to 78.4 percent from 98.0 percent and is reduced by 19.6 percent; the average daily oil production of a single well is increased from 0.44t/d to 3.91t/d and increased by 3.47t/d, and the cumulative oil increase 10158t (Table 3) is still effective at present.
TABLE 32017 statistics of gel nitrogen foam and in-situ microemulsion implementation effect of petroleum Jidonnan castle oil field
In conclusion, the development phenomena of water content increase and oil yield decrease of the oil well can be effectively controlled by applying the gel foam and in-situ microemulsion combined oil well yield increasing method, and the oil field development effect is improved.
Evaluation of the Properties of the Nitrogen foam System
1. Relationship between nitrogen foam system performance and concentration
The relationship between the foam volume and the foam half-life period of the nitrogen foam system and the concentration of the foaming agent is shown in Table 4, the foam volume and the foam half-life period are increased along with the increase of the concentration of the foaming agent HN-1, the increase range of the foam volume and the foam half-life period is reduced when the concentration of the foaming agent HN-1 is more than 0.4%, the performance and the economic benefit are comprehensively considered, and the concentration of the foaming agent HN-1 is selected to be between 0.4% and 0.8% when the nitrogen foam system is applied.
TABLE 4 relationship of foam volume, foam half-life and blowing agent concentration for nitrogen foam systems
| Concentration of foaming agent/%) | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 |
| Foam volume/ml | 180 | 220 | 260 | 420 | 550 | 620 | 670 | 690 | 720 |
| Foam half life/ |
80 | 95 | 120 | 135 | 140 | 142 | 145 | 150 | 153 |
2. Relationship between performance and concentration of enhanced nitrogen foam system
The enhanced nitrogen foam system comprises a polymer enhanced nitrogen foam system and a gel enhanced nitrogen foam system, the relationship between the foam volume, the foam half-life period and the concentration is shown in Table 5, the foam volume is reduced to a certain extent along with the increase of the concentration of the polymer and the cross-linking agent, but the foam half-life period is obviously increased, the stability of the nitrogen foam is obviously improved, and the effective period can be effectively prolonged when the enhanced nitrogen foam system is applied on site. Comprehensively, the concentration of the polymer is selected to be between 0.1 and 0.3 percent, and the concentration of the cross-linking agent is selected to be between 0.025 and 0.075 percent.
The formula of the reinforced nitrogen foam system comprises: 0.4 to 0.8 percent of foaming agent HN-1, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent.
TABLE 5 foam volume, half-life and concentration relationship for enhanced nitrogen foam systems
3. Influence of gas-liquid ratio on resistance coefficient of gel nitrogen foam system
FIG. 2 shows the influence of different gas-liquid ratios on the resistance factor of a gel nitrogen foam system, wherein the experimental temperature is 100 ℃, and the gas injection speed is 1mL/min, and it can be seen that when the gas-liquid ratio is 1: 1-3: 1, the resistance factor is high, and the plugging effect on the stratum is good, so that when the gas-liquid ratio is applied on site, the gas-liquid ratio is 1: 1-3: 1.
4. Profile adjustment capability of gel nitrogen foam system
Table 6 shows the ability of the gel nitrogen foam system to adjust the profile, and it can be seen that the larger the difference in permeability, the larger the change in the split flow rate between the high permeable layer and the low permeable layer before and after the injection of the gel nitrogen foam system, i.e. the greater the seepage resistance established by the gel nitrogen foam system in the high permeable layer, the greater the resistance to large blockage. Therefore, the gel nitrogen foam system has strong capability of adjusting the profile, and the larger the permeability level difference is, the larger the profile improvement amplitude is. This property is very suitable for use in water shutoff in oil wells or in profile control in water wells.
TABLE 6 relationship between split flow rate and permeability before and after injection of gel nitrogen foam system
Third, evaluating the performance of the in-situ microemulsion surfactant
The microemulsion is a thermodynamic stable system formed by mixing components such as oil, water, surfactant, auxiliary agent and the like. Compared with emulsion, the microemulsion has stronger capability of solubilizing crude oil, smaller emulsified particle size, more stability, higher oil displacement efficiency and good adaptability to high-temperature and low-permeability oil reservoirs.
1. The in-situ microemulsion surfactant SH6 has high interfacial activity
The in-situ microemulsion surfactant SH6 has high interfacial activity. The SH6 solution prepared from the sewage generated by the oil field has the interfacial tension of 10 at the concentration of 100mg/L-2mN/m order of magnitude, and when the concentration is more than 300mg/L, the interfacial tension is 10-4In the order of mN/m, the SH6 solution has high interfacial activity in a low-concentration area and a wide window of ultralow interfacial tension concentration (Table 7).
TABLE 7 interfacial tension of SH6 solution as a function of concentration
2. Concentration range of in-situ microemulsion surfactant SH6 for forming microemulsion
Table 8 is the case where the in situ microemulsion surfactant SH6 produced microemulsions with crude oil in the concentration range of 0.2% to 5%. The experimental oil-water ratio was 1:1, and the volumes of the initial aqueous phase and the oil phase were 10 mL. As can be seen from Table 8, at a concentration of 0.2%, the SH6 solution was poorly able to solubilize the crude oil, failing to form a stable microemulsion, and the oil-water phase volume was still maintained at 10mL each. Within the range of 0.3-5% of the concentration of the in-situ microemulsion surfactant SH6, the SH6 solution and crude oil can form a middle-phase microemulsion. The volume of the formed microemulsion is increased along with the increase of the concentration of the in-situ microemulsion surfactant SH6, and the in-situ microemulsion surfactant SH6 is selected to be 0.5-4% in field application.
TABLE 8 Effect of in situ microemulsion surfactant SH6 concentration on microemulsion volume
3. Particle size and distribution of microemulsions
FIG. 3 is a particle size distribution diagram of Winsor type III microemulsion formed by 3% in situ microemulsion surfactant SH 6. As can be seen from the data in the figure, the microemulsion has small particle size and narrow distribution range, the particle size range is mainly distributed between 40 nm and 100nm, and the number of droplets with the particle size of 40 nm to 60nm is the largest, which accords with the particle size distribution range of the microemulsion. The microemulsion has small particle size, good long-term stability, belongs to a thermodynamic stable system, and has strong capability of solubilizing crude oil and much higher oil washing efficiency than emulsion. The conventional emulsion belongs to a thermodynamically unstable system, and the emulsion droplets have larger particle size and wide distribution range which is mainly distributed above 100 nm; along with the prolonging of the standing time, the liquid drops are gradually merged, and when the liquid drops are merged to a certain degree, the liquid drops are obviously layered, so that demulsification is generated.
4. Oil washing effect of microemulsion on oil layer sand
Oil layer sand of saturated crude oil soaked in different chemical systems can strip crude oil adsorbed in rock from the surface of the rock, and show different oil washing capacities (table 9). As can be seen from Table 9, the polymer system has no oil washing effect, the oil washing efficiency of the ternary composite system with low interfacial tension is 59.0%, the oil washing efficiency of the microemulsion system is high (more than 79%), and the oil washing efficiency of the serial in-situ microemulsion surfactant SH6 microemulsion system can reach more than 84%.
TABLE 9 oil wash efficiency for different chemical systems
5. Oil displacement experiment of combined application of foam system and in-situ microemulsion surfactant
Table 10 shows the results of the flooding experiments using a 3-fold permeability step (100md/300md) artificial interlaminar heterogeneous model, different single chemical systems, and their combined applications. The micro-emulsion flooding (5000mg/L in-situ micro-emulsion surfactant SH6+1000mg/L polymer) improves the recovery ratio by 15.31%, the gel foam flooding (0.5% foaming agent HN-1+ 0.2% polymer + 0.05% cross-linking agent) improves the recovery ratio by 17.24%, and the gel foam system and the micro-emulsion combined flooding mode improve the recovery ratio by 22.46%, which is far higher than that of single micro-emulsion flooding and gel foam flooding. The gel foam flooding plugging high-permeability layer has strong effect, the effect of enlarging swept volume is obvious, and the microemulsion flooding has ultralow interfacial tension, stronger capability of solubilizing crude oil and higher oil displacement efficiency; the gel foam system and the microemulsion combined displacement mode synergistically play a role in higher oil displacement efficiency of the microemulsion system on the basis of expanding swept volume, and the recovery ratio can be greatly improved. The injection mode of the gel foam system + microemulsion system + gel foam system is therefore recommended for field use.
Table 10 oil displacement experiment of gel foam system and microemulsion system and their combined application
Claims (3)
1. A method for increasing the production of an oil well by combining gel foam and in-situ microemulsion is characterized by comprising the following steps:
(1) injecting 100m into oil well3～300m3The nitrogen gas of (2) to form a front nitrogen gas slug, wherein the oil deposit and development parameters of the oil well are as follows: the oil reservoir temperature is 50-100 ℃, the porosity is 15-35%, the permeability is 30-1500 md, the water content is more than 90%, and the extraction degree is<37%；
(2) Injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (1) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3Wherein the gel foaming agent in the gel foaming agent aqueous solution consists of the following components in percentage by mass: 10.4-0.8% of foaming agent HN, 0.1-0.3% of polymer and 0.025-0.075% of cross-linking agent, wherein the mass percentages of the components are the percentages of the components in the total mass of the gel foaming agent aqueous solution, the foaming agent HN-1 is fatty alcohol polyoxyethylene ether sodium carboxylate, the polymer is a temperature-resistant salt-resistant polymer ZL-II, the relative molecular mass of the polymer is 2400 ten thousand, the hydrolysis degree of the polymer is 22%, and the cross-linking agent is an organic phenolic cross-linking agent;
(3) according to the volume ratio of 1: 1-3: 1 of nitrogen to polymer foaming agent aqueous solution, certain volume of nitrogen and polymer are mixedInjecting a mixed system of the polymer foaming agent aqueous solution into the oil well in the step (2) to form a polymer nitrogen foam slug, wherein the volume of the polymer foaming agent aqueous solution in the mixed system is 400m3～800m3Wherein the polymer foaming agent in the polymer foaming agent aqueous solution consists of the following components in percentage by mass: 10.4-0.8% of foaming agent HN-1 and 0.1-0.3% of polymer, wherein the mass percentages of the components are the percentages of the components in the total mass of the polymer foaming agent aqueous solution, the foaming agent HN-1 is fatty alcohol polyoxyethylene ether sodium carboxylate, the polymer is a temperature-resistant salt-resistant polymer ZL-II, the relative molecular mass of the polymer is 2400 ten thousand, and the degree of hydrolysis is 22%;
(4) injecting 500m into the oil well in the step (3)3～1000m3The in-situ microemulsion slug is formed by the in-situ microemulsion aqueous solution, wherein the in-situ microemulsion in the in-situ microemulsion aqueous solution consists of the following components in percentage by mass: 60.5-4% of in-situ microemulsion surfactant SH and 0.1-0.3% of polymer, wherein the mass percentages of the components are the percentage of the total mass of the in-situ microemulsion aqueous solution, the in-situ microemulsion surfactant SH6 is prepared by mixing polyether carboxylate/sulfonate anionic-nonionic surfactant and cationic surfactant, the ratio of the polyether carboxylate/sulfonate anionic-nonionic surfactant to the cationic surfactant is 1: 0.5-1: 2, the polymer is a temperature-resistant salt-resistant polymer ZL-II, the relative molecular mass of the polymer is 2400 ten thousand, and the hydrolysis degree is 22%;
(5) injecting a mixed system of a certain volume of nitrogen and a gel foaming agent aqueous solution into the oil well in the step (4) according to the volume ratio of the nitrogen to the gel foaming agent aqueous solution of 1: 1-3: 1 to form a gel nitrogen foam slug, wherein the volume of the gel foaming agent aqueous solution in the mixed system is 300m3～600m3Wherein the gel foaming agent in the gel foaming agent aqueous solution consists of the following components in percentage by mass: 10.4 to 0.8 percent of foaming agent HN-1, 0.1 to 0.3 percent of polymer and 0.025 to 0.075 percent of cross-linking agent, wherein the mass percent of each component is that each component accounts for the total mass of the gel foaming agent aqueous solution, the foaming agent HN-1 is fatty alcohol polyoxyethylene ether sodium carboxylate, the polymer is a temperature-resistant salt-resistant polymer ZL-II, and the polymer is a polymer with the characteristics of temperature resistance and salt resistanceThe relative molecular mass is 2400 ten thousand, the hydrolysis degree is 22 percent, and the cross-linking agent is an organic phenolic cross-linking agent.
2. The method of oil well stimulation using gel foam in combination with an in situ microemulsion of claim 1, wherein: the total volume of the gel foaming agent aqueous solution in the step (2), the polymer foaming agent aqueous solution in the step (3), the in-situ microemulsion aqueous solution in the step (4) and the gel foaming agent aqueous solution in the step (5) is 1500m3～3000m3。
3. The method of oil well stimulation using gel foam in combination with an in situ microemulsion of claim 1, wherein: the water used in preparing the gel foaming agent aqueous solution, the polymer foaming agent aqueous solution and the in-situ microemulsion aqueous solution is oil field injection sewage.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4389320A (en) * | 1979-12-04 | 1983-06-21 | Phillips Petroleum Company | Foamable compositions and formations treatment |
| CN101675140A (en) * | 2007-04-25 | 2010-03-17 | 贝克休斯公司 | Original position microemulsion as spacer pad |
| CN104152126A (en) * | 2014-07-24 | 2014-11-19 | 中国石油天然气股份有限公司 | Foam profile control system suitable for advanced profile control of oilfield and preparation method of foam profile control system |
| CN105038752A (en) * | 2015-06-16 | 2015-11-11 | 中国石油化工股份有限公司 | Compound oil-displacing agent for high temperature reservoir and compound oil-displacing system |
| CN106050202A (en) * | 2016-05-31 | 2016-10-26 | 张荣斌 | Gel-air foam oil displacement method |
| CN106150466A (en) * | 2016-08-23 | 2016-11-23 | 中国石油化工股份有限公司 | The thick oil thermal recovery method of gel foam suppression bottom water coning |
| CN107859507A (en) * | 2016-09-22 | 2018-03-30 | 中国石油化工股份有限公司 | Improve the method for increasing of oil well single well productivity |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103030916B (en) * | 2012-11-23 | 2015-08-05 | 中国石油天然气股份有限公司 | A kind of gelatinous composition and containing its nitrogen foam gel Complex Temporary Blocking agent |
| CN106867486A (en) * | 2017-04-21 | 2017-06-20 | 西南石油大学 | A kind of frothy gel well workover method for increasing made with water blockoff connection and its application |
-
2018
- 2018-04-25 CN CN201810378287.XA patent/CN108410439B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4389320A (en) * | 1979-12-04 | 1983-06-21 | Phillips Petroleum Company | Foamable compositions and formations treatment |
| CN101675140A (en) * | 2007-04-25 | 2010-03-17 | 贝克休斯公司 | Original position microemulsion as spacer pad |
| CN104152126A (en) * | 2014-07-24 | 2014-11-19 | 中国石油天然气股份有限公司 | Foam profile control system suitable for advanced profile control of oilfield and preparation method of foam profile control system |
| CN105038752A (en) * | 2015-06-16 | 2015-11-11 | 中国石油化工股份有限公司 | Compound oil-displacing agent for high temperature reservoir and compound oil-displacing system |
| CN106050202A (en) * | 2016-05-31 | 2016-10-26 | 张荣斌 | Gel-air foam oil displacement method |
| CN106150466A (en) * | 2016-08-23 | 2016-11-23 | 中国石油化工股份有限公司 | The thick oil thermal recovery method of gel foam suppression bottom water coning |
| CN107859507A (en) * | 2016-09-22 | 2018-03-30 | 中国石油化工股份有限公司 | Improve the method for increasing of oil well single well productivity |
Non-Patent Citations (2)
| Title |
|---|
| Water Control of Horizontal Wells Using Foam-Gel: Lessons Learnt in a Heavy Oil Reservoir with Strong Waterdrive;Bo Deng;《Society of Petroleum Engineers》;20171019;1-8 * |
| 多段塞泡沫凝胶调驱工艺参数优化研究;刘军龙;《地下水》;20170125;第39卷(第1期);133-135 * |
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