Oil reservoir energy enhancement, unblocking, viscosity reduction and drainage aid composite agent, its preparation method and application

Abstract

This invention discloses a composite agent for enhancing oil reservoir capacity, unblocking, reducing viscosity, and aiding drainage, along with its preparation method and application. The composite agent comprises agent A, agent B, agent C, and agent D. Agent A consists of urea, urease, and sodium bicarbonate in a mass ratio of (4.5-5.5):(0.8-1.2):(3.5-4.5); agent B consists of p-aminobenzenesulfonic acid, ethylenediaminetetramethylenephosphonic acid, and polydimethylsiloxane in a mass ratio of (8-10):(0.8-1):(1-1.2); agent C consists of sodium dodecyl sulfonate and diethylenetriamine in a mass ratio of (0.8-1):(1.8-2.2); and agent D consists of polyvinylpyrrolidone and sodium dodecyl sulfate in a mass ratio of (1-1.2):(2-3). This invention reacts under oil reservoir conditions to form a high-pressure multiphase foam system, temporarily plugging and sealing high-permeability layers, and then sequentially utilizing and tapping into secondary high-permeability layers and low-permeability layers, thereby improving the effectiveness of various oil well production enhancement measures.

Description

Technical Field

[0001] This invention belongs to the field of oilfield development technology. Specifically, this invention relates to an integrated composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage, as well as its preparation method and application. Background Technology

[0002] As oilfields are continuously developed and reservoir fluids (oil, gas, and water) are continuously extracted, reservoir energy decreases in a gradient manner. When the reservoir energy decreases to a certain level, due to capillary flow resistance, the existing reservoir energy can no longer drive the formation fluids, causing a sharp drop in the produced fluid volume. In some cases, due to the difference in oil and water mobility ratios, although the fluid volume decrease is not significant, the water cut increases significantly. In other words, due to the decrease in reservoir energy, the pores that were originally able to flow become blocked, or due to the decrease in formation pressure, the droplet diameter that was originally compatible with the formation pore diameter no longer matches, thereby damaging the reservoir and significantly reducing production capacity.

[0003] Meanwhile, during the displacement and extraction of crude oil, the relatively lighter components in the crude oil preferentially flow and are extracted. The longer the extraction time, the greater the retention and deposition of the relatively heavier components in the crude oil in the near-wellbore zone during the flow and extraction of fluids (such as "dead oil" near the well), causing "secondary" damage to the oil well. Furthermore, the damage caused during drilling, completion, and perforation processes after the oil layer is opened is also one of the main reasons for the decline in oil well productivity. In addition, during the development of the oil field, the introduction of incompatible fluids into the well can easily generate various types of scale (inorganic scale such as calcium, magnesium, and iron, and organic scale such as asphalt, gum, and wax) that clog the reservoir and reduce oil well productivity.

[0004] Therefore, it is evident that declining reservoir productivity, thick and difficult-to-flow oil, and various blockages are the key factors causing the decline in oil well production, and also the true root cause of oil well blockages. The key to fundamentally resolving these blockages and restoring and increasing oil well production lies in technological breakthroughs in restoring reservoir energy, reducing crude oil viscosity, decreasing oil flow resistance, and resolving various blockages in the reservoir. This will fundamentally restore oil well production and ultimately improve crude oil recovery rate and extraction rate. Summary of the Invention

[0005] The present invention aims to at least partially solve one of the technical problems in the related art. To this end, the present invention provides an integrated composite agent for oil reservoir energy enhancement, unblocking, viscosity reduction and drainage, as well as its preparation method and application.

[0006] The present invention adopts the following technical solution:

[0007] Firstly,

[0008] This invention provides a composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage, comprising:

[0009] Agent A: The components are urea, urease, and sodium bicarbonate, with a mass ratio of (4.5-5.5):(0.8-1.2):(3.5-4.5).

[0010] Agent B: The components are p-aminobenzenesulfonic acid, ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane, with a mass ratio of (8-10):(0.8-1):(1-1.2).

[0011] Agent C: The components are sodium dodecyl sulfonate and diethylenetriamine, with a mass ratio of (0.8-1):(1.8-2.2).

[0012] Agent D: The components are polyvinylpyrrolidone and sodium dodecyl sulfate, with a mass ratio of (1-1.2):(2-3).

[0013] In some embodiments, the integrated oil layer energy-enhancing, unblocking, viscosity-reducing, and drainage-aiding compound agent comprises:

[0014] Agent A: The components are urea, urease and sodium bicarbonate, with a mass ratio of 5:1:4;

[0015] Agent B: The components are p-aminobenzenesulfonic acid, ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane, with a mass ratio of 8:1:1;

[0016] Agent C: The components are sodium dodecyl sulfonate and diethylenetriamine, with a mass ratio of 1:2;

[0017] Agent D: The components are polyvinylpyrrolidone and sodium dodecyl sulfate, with a mass ratio of 1:2.5.

[0018] Secondly,

[0019] This invention also provides a method for preparing the above-mentioned integrated composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage, comprising:

[0020] Preparation of Agent A: First, add urea and sodium bicarbonate to the reaction vessel and stir at 23-27℃ for 30-45 minutes at a stirring speed of 30-60 r / min; then add urease to the reaction vessel and continue stirring at 23-27℃ for 45-60 minutes to obtain Agent A.

[0021] Preparation of Agent B: First, add p-aminobenzenesulfonic acid to the reaction vessel and stir at 23-27℃ for 30-45 minutes at a stirring speed of 30-60 r / min; then add ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane to the reaction vessel and continue stirring at 23-27℃ for 45-60 minutes to obtain Agent B.

[0022] Preparation of Agent C: First, add sodium dodecyl sulfonate to the reaction vessel and stir at 45-55℃ for 30-45 min at a stirring speed of 30-60 r / min; then add diethylenetriamine to the reaction vessel and continue stirring at 45-55℃ for 45-60 min, cool to room temperature to obtain Agent C;

[0023] Preparation of Agent D: First, add polyvinylpyrrolidone to the reaction vessel and stir at 45-55℃ for 30-45 min at a stirring speed of 30-60 r / min; then add sodium dodecyl sulfate to the reaction vessel and continue stirring at 45-55℃ for 45-60 min, and cool to room temperature to obtain Agent D.

[0024] In some embodiments, the preparation method of the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid includes:

[0025] Preparation of Agent A: First, add urea and sodium bicarbonate to the reaction vessel and stir at 25°C for 30 minutes at a stirring speed of 45 r / min; then add urease to the reaction vessel and continue stirring at 25°C for 45 minutes to obtain Agent A.

[0026] Preparation of Agent B: First, add p-aminobenzenesulfonic acid to the reaction vessel and stir at 25°C for 30 min at a stirring speed of 45 r / min; then add ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane to the reaction vessel and continue stirring at 25°C for 45 min to obtain Agent B.

[0027] Preparation of Agent C: First, sodium dodecyl sulfonate was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 60 r / min; then, diethylenetriamine was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent C was obtained.

[0028] Preparation of Agent D: First, polyvinylpyrrolidone was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 45 r / min; then sodium dodecyl sulfate was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent D was obtained.

[0029] Thirdly,

[0030] The present invention also provides an application method for the above-mentioned oil layer energy enhancement, unblocking, viscosity reduction and drainage aid composite integrated agent, wherein the mass ratio of the applied agent A, agent B, agent C and agent D is (3-4): (3-4): (1.5-2.5): (1.5-2).

[0031] In some implementations, the mass ratio of Agent A, Agent B, Agent C, and Agent D used is 3.5:3:2:1.5.

[0032] In some application method embodiments, agent A is prepared with water to form a 10% solution, i.e., solution A, for later use; agent B is prepared with water to form a 12% solution, i.e. solution B, for later use; agent C is prepared with water to form a 5% solution, i.e. solution C, for later use; and agent D is prepared with water to form a 5% solution, i.e. solution D, for later use.

[0033] In some application embodiments, the application method includes:

[0034] S1: Inject solution A into the oil layer;

[0035] S2: After solution A is injected, a mixture of solutions B and C is injected into the oil layer. The amount of solution B used in the mixture is 50% of the total amount of solution B.

[0036] S3: Continue to inject the mixture of solution B and solution D, in which the amount of solution B used is 50% of the total amount of solution B.

[0037] In some implementations of the application methods,

[0038] The preparation method of solution A includes the following steps: adding a portion of water to a mixing tank, maintaining the temperature at 25-28℃, preferably 25℃, adding agent A to the mixing tank at an addition rate of 45-55 kg / min, preferably 50 kg / min, then adding the remaining water to make the concentration of agent A 10%, maintaining the temperature at 25-28℃, preferably 25℃, and stirring at 45-65 r / min, preferably 60 r / min, to prepare solution A;

[0039] The preparation method of solution B includes the following steps: adding a portion of water to a mixing tank, maintaining the temperature at 25-30℃, preferably 25℃, adding agent B to the mixing tank at an addition rate of 45-55 kg / min, preferably 50 kg / min, then adding the remaining water to make the concentration of agent B 12%, maintaining the temperature at 25-30℃, preferably 25℃, and stirring at 45-65 r / min, preferably 60 r / min, to prepare solution B;

[0040] The preparation method of solution C includes the following steps: adding some water to a mixing tank, maintaining the temperature at 25-30℃, preferably 25℃, adding agent C to the mixing tank at an addition rate of 15-25 kg / min, preferably 20 kg / min, adding water to make the concentration of agent C 5%, maintaining the temperature at 25-30℃, preferably 25℃, and stirring at 45-65 r / min, preferably 60 r / min, to prepare solution C;

[0041] The preparation method of solution D includes the following steps: adding some water to a mixing tank, maintaining the temperature at 25-30℃, preferably 25℃, adding agent D to the mixing tank at an addition rate of 10-15 kg / min, preferably 10 kg / min, adding water to make the concentration of agent D 5%, maintaining the temperature at 25-30℃, preferably 25℃, and stirring at 45-65 r / min, preferably 60 r / min, to prepare solution D.

[0042] In some application embodiments, the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid is suitable for the exploitation of oil reservoirs in the mid-to-late stages of oilfield development. The integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid of this invention, when applied to the exploitation of low-yield, inefficient, and difficult-to-access oil reservoirs in the mid-to-late stages of oilfield development, can still achieve significant production increases.

[0043] This invention relates to a composite agent for enhancing oil reservoir capacity, unblocking, reducing viscosity, and aiding drainage.

[0044] In solution A, urea undergoes a chemical reaction under reservoir conditions, aided by urease, to produce gas and replenish reservoir energy. However, urea typically decomposes slowly under reservoir conditions with the aid of urease, producing very little gas. Therefore, its effect on replenishing reservoir reserves and improving oil recovery is not significant, mainly because urease struggles to maintain high activity under reservoir conditions, and its activity is greatly affected by the ambient pH. This invention creatively adds sodium bicarbonate and adjusts the ratio of urea, urease, and sodium bicarbonate to maintain the pH within the optimal range of 6.8-7.8, ensuring that urease maintains maximum activity under reservoir conditions and thus improving energy enhancement and oil recovery.

[0045] The reaction mechanism involved in Agent A is as follows: Under the conditions of pH 6.8-7.8, urea decomposes with the help of urease to generate CO2, H2O, N2, and NO2.

[0046] In solution B, p-aminobenzenesulfonic acid dissolves reservoir rocks (carbonate rocks, clay minerals, etc.), increasing permeability. It also forms a surfactant with the aromatic components of crude oil (furans, ketones), reducing oil flow resistance. Furthermore, p-aminobenzenesulfonic acid disperses and dissolves reservoir clay minerals, preventing clay swelling and migration damage (clogging). Ethylenediaminetetramethylenephosphonic acid complexes iron, magnesium, and calcium ions, preventing acid-sensitive damage (clogging). Polydimethylsiloxane disperses and dissolves asphalt resin wax, removing organic blockage. These three components work synergistically to form a protective closed loop targeting different types of reservoir damage. The unblocking and surface-active effects (p-aminobenzenesulfonic acid), the complexing effect (ethylenediaminetetramethylenephosphonic acid), and the dispersing and dissolving effect (polydimethylsiloxane) collectively improve the oil-water-rock interface properties, synergize fluid flow channels, reduce flow resistance, and increase reservoir productivity.

[0047] In solution C, the surface activity of sodium dodecyl sulfonate disperses and dissolves the reservoir crude oil, allowing the crude oil molecular chains to fully extend and expose more metal ion binding sites. With the help of diethylenetriamine's complexation effect on transition metal ions, the content of target elements (such as nickel) in the crude oil molecular structure is reduced. After the removal of transition metal ions, the cross-linking effect between crude oil molecules is weakened, and sodium dodecyl sulfonate can more easily penetrate and disperse the remaining molecular clusters, ultimately changing the occurrence state of crude oil molecules, reducing the number of single molecules aggregated in crude oil molecular clusters, and thus reducing the viscosity of crude oil.

[0048] In solution D, a low-density foam system (0.65-0.85 g / cm³) is formed by dynamic action. 3 After implementing these measures, wells are opened to increase recovery speed and recovery rate.

[0049] The present invention has the following advantages and beneficial effects;

[0050] This invention is a composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage. It can be widely applied throughout the entire oilfield development process to relieve reservoir damage (blockage) at various stages and increase single-well production. By leveraging the comprehensive properties of the agent, it can tap the potential of the blocked "target layer," fundamentally solving the technical difficulties of "difficulty in the agent entering the target layer, low reaction degree, and inability to expel reaction products," thereby maximizing the production-increasing effect of the measures.

[0051] This invention relates to a composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage. Under reservoir conditions, it reacts to form a high-pressure multiphase foam system, temporarily plugging and sealing high-permeability layers, then sequentially activating and tapping into secondary high-permeability layers and low-permeability layers, thereby improving the effectiveness of various oil well production enhancement measures. Specifically, the multiphase foam's temporary plugging and sealing effect has the following significant characteristics: First, the foam has excellent fluidity, allowing it to penetrate deep into every corner of the reservoir, ensuring a sealing effect; second, the multiphase foam system has strong stability, maintaining its effectiveness for a long time under formation temperature, high pressure, and high salinity environments; finally, after the treatment, the multiphase foam's temporary plugging effect is easily removed, without causing permanent blockage to the oil well, thus fully utilizing the reservoir's potential. Attached Figure Description

[0052] Figure 1 The diffusion of the droplet when it was dropped into the beaker in Experiment 5-1;

[0053] Figure 2 The extent of reaction 15 minutes after the liquid droplets of Experiment 5-1 were added to the beaker;

[0054] Figure 3 The diffusion of the droplet in Experiment 5-2 when it was dropped into the beaker;

[0055] Figure 4 The degree of reaction is shown 15 minutes after the droplets of Experiment 5-2 were added to the beaker. Detailed Implementation

[0056] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0057] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0058] Unless otherwise specified, the materials, reagents, and apparatus used in the following examples can be obtained commercially or prepared according to methods published in the literature.

[0059] In this document, when values ​​are described as ranges, it should be understood that such disclosure includes disclosure of all possible subranges within that range, as well as the specific numerical values ​​falling within that range, regardless of whether the specific numerical value or specific subrange is explicitly specified.

[0060] Unless otherwise defined, all technical and scientific terms used herein have the meanings commonly understood by one of ordinary skill in the art to which this invention pertains.

[0061] Unless otherwise specified, all solutions mentioned in this article are aqueous solutions, and all concentrations mentioned are mass concentrations.

[0062] Example 1

[0063] The integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid includes:

[0064] Agent A: The components are urea, urease (Beijing Solarbio Technology Co., Ltd., urease activity: ≥50u / mg) and sodium bicarbonate, with a mass ratio of 5:1:4;

[0065] Agent B: The components are p-aminobenzenesulfonic acid, ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane, with a mass ratio of 8:1:1;

[0066] Agent C: The components are sodium dodecyl sulfonate and diethylenetriamine, with a mass ratio of 1:2;

[0067] Agent D: The components are polyvinylpyrrolidone and sodium dodecyl sulfate, with a mass ratio of 1:2.5.

[0068] This integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid comprises:

[0069] Preparation of Agent A: First, add urea and sodium bicarbonate to the reaction vessel and stir at 25°C for 30 minutes at a stirring speed of 45 r / min; then add urease to the reaction vessel and continue stirring at 25°C for 45 minutes to obtain Agent A.

[0070] Preparation of Agent B: First, add p-aminobenzenesulfonic acid to the reaction vessel and stir at 25°C for 30 min at a stirring speed of 45 r / min; then add ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane to the reaction vessel and continue stirring at 25°C for 45 min to obtain Agent B.

[0071] Preparation of Agent C: First, sodium dodecyl sulfonate was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 60 r / min; then, diethylenetriamine was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent C was obtained.

[0072] Preparation of Agent D: First, polyvinylpyrrolidone was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 45 r / min; then sodium dodecyl sulfate was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent D was obtained.

[0073] Example 2

[0074] The application method of the integrated composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage, wherein the mass ratio of agent A: agent B: agent C: agent D is 3.5:3:2:1.5. Agents A, B, C, and D were all prepared in Example 1.

[0075] Preparation of solution A: Add 3m to the mixing tank 3 Water, kept at a constant temperature of 25℃, was added to the mixing tank at a rate of 50 kg / min, until the water level reached 3.5 m. 3 At a constant temperature of 25℃ and a stirring speed of 60 r / min, a 3.5m solution was prepared. 3 10% A solution (into storage tank).

[0076] Preparation of solution B: Add 2.5m to the mixing tank. 3 Water, kept at a constant temperature of 25℃, was used to uniformly add 360 kg of agent B to the mixing tank at a rate of 50 kg / min; water was added until the volume reached 3 m³. 3 Maintain a constant temperature of 25℃ and a stirring speed of 60 r / min; prepare a 3m solution. 3 12% B solution (input into storage tank).

[0077] Preparation of solution C: Add 1.5m to the mixing tank. 3 Water, kept at a constant temperature of 25℃, is used to uniformly add 100 kg of agent C to the mixing tank at a rate of 20 kg / min; water is added until it reaches a depth of 2 m. 3 Maintain a constant temperature of 25℃ and a stirring speed of 60 r / min; prepare a 2m solution. 3 5% C solution (into storage tank).

[0078] Preparation of solution D: Add 1m to the mixing tank 3Water, kept at a constant temperature of 25℃, was used to uniformly add 75 kg of agent D to the mixing tank at a rate of 10 kg / min; water was added until the volume reached 1.5 m. 3 The mixture was kept at a constant temperature of 25℃ and stirred at a speed of 60 r / min to prepare a 1.5 m solution. 3 5% D solution (input into storage tank).

[0079] When adding to the oil layer,

[0080] S1: Inject solution A into the oil layer. A large amount of solution A enters the high-permeability layer, and a small amount of solution A enters the secondary high-permeability layer and the low-permeability layer.

[0081] S2: After solution A is injected, a mixture of solutions B and C is injected into the oil layer. The amount of solution B in the mixture is 50% of the total amount of solution B. Similarly, a large amount of agents B and C preferentially enter the high-permeability layer. After agents A, B, and C are mixed, a large amount of gas is released by the reaction of agent A, forming a high-pressure multiphase foam system. The high-permeability layer generates a large amount of gas and a large pressure increase, forcing the subsequently injected solutions B and C to enter the secondary high-permeability layer and the low-permeability layer, greatly improving the utilization potential of the secondary high-permeability layer and the low-permeability layer. At the same time, during the injection of solution A, a small amount will enter the secondary high-permeability layer and the low-permeability layer. After mixing with the later injected solutions B and C, the gas generation process by the reaction of agent A plays a dynamic stirring role, improving the reaction degree, and ultimately achieving the purpose of temporarily plugging the high-permeability layer and tapping the potential of the low-permeability layer.

[0082] S3: Continue injecting the mixture of solution B and solution D, with solution B accounting for 50% of the total amount of solution B used in the mixture; fully utilize the composite properties of the integrated agent to maximize the production of a single oil well, providing strong technical support for the high-quality, high-efficiency, and sustainable development of the oilfield.

[0083] Experiment Example 1: Evaluation of the gas production effect of urea decomposition under different indoor conditions

[0084] Experimental apparatus: TCY-WK1000 thermo-pressure reactor (pressure range 0.1-5.0MPa, temperature range 0-350℃, volume 1000ml)

[0085] Experimental Example 1-1: Weigh 100 ml of 10% urea solution and 200 ml of 1% urease solution, add them to a thermo-pressure reactor, set the temperature to 25℃, measure the pH value, record the time it takes for the pressure of the thermo-pressure reactor to rise to 0.5 MPa, and record the time it takes for the reaction to start and end.

[0086] Experimental Example 1-2: Weigh 100ml of 10% urea solution, 200ml of 1% urease solution, and 160ml of 5% sodium bicarbonate solution, add them to a thermo-pressure reactor, set the temperature to 25℃, measure the pH value, record the time taken for the thermo-pressure reactor pressure to rise to 0.5MPa, and record the time taken from the start of the reaction to the end of the reaction.

[0087] Experimental Examples 1-3: Weigh 100 ml of 10% urea solution, 200 ml of 1% urease solution, and 160 ml of 5% ammonium bicarbonate solution, add them to a thermo-pressure reactor, set the temperature to 25℃, measure the pH value, record the time taken for the pressure of the thermo-pressure reactor to rise to 0.5 MPa, and record the time taken from the start of the reaction to the end of the reaction.

[0088] Experimental Examples 1-4: Weigh 100 ml of 10% urea solution, 200 ml of 1% urease solution, and 160 ml of 5% potassium bicarbonate solution, add them to a thermo-pressure reactor, set the temperature to 25℃, measure the pH value, record the time taken for the thermo-pressure reactor pressure to rise to 0.5 MPa, and record the time taken from the start of the reaction to the end of the reaction.

[0089] Experimental Examples 1-5: Weigh 100 ml of 10% urea solution, 200 ml of 1% urease solution, and 160 ml of 5% calcium bicarbonate solution, add them to a thermo-pressure reactor, set the temperature to 25℃, measure the pH value, record the time taken for the pressure of the thermo-pressure reactor to rise to 0.5 MPa, and record the time taken from the start of the reaction to the end of the reaction.

[0090] The evaluation results are shown in Table 1 below.

[0091] Table 1 Evaluation of the gas production effect of urea decomposition under different conditions

[0092]

[0093] As can be seen from Table 1, urea decomposes into gas at the fastest rate and in the largest amount under the conditions of urease and sodium bicarbonate solution, which best meets the actual application requirements of oilfield development, while the other similar salts cannot meet the actual application requirements of oilfield development.

[0094] Experiment Example 2: Viscosity Reduction Effect Evaluation Experiment

[0095] Dehydrated oil samples were taken from three wells: Jin 45-2-7, Leng 37-10, and Du 32-1-3.

[0096] The oil sample was kept at a constant temperature of 50℃, and its viscosity was determined in accordance with the petroleum industry standard SY / T0520-2008.

[0097] The oil sample was mixed with 1.0% EDTA solution, 1.0% sodium dodecyl sulfonate solution, 1.0% C solution, 1.0% C1 solution, 1.0% C2 solution, 1.0% C3 solution, and 1.0% C4 solution respectively, with a volume ratio of 3:7. The mixture was kept at a constant temperature of 50℃, and the viscosity was measured according to the petroleum industry standard SY / T0520-2008. The viscosity reduction rate was calculated, and the results are shown in Table 2.

[0098] Table 2 Evaluation of viscosity-reducing effects of different reagents on crude oil (heavy oil)

[0099]

[0100] Agent C in solution C consists of sodium dodecyl sulfonate and diethylenetriamine in a mass ratio of 1:2.

[0101] The C1 agent in the C1 solution consists of sodium dodecyl sulfonate and diethylenetriamine in a mass ratio of 1:1.

[0102] The C2 agent in the C2 solution consists of sodium dodecyl sulfonate and diethylenetriamine in a mass ratio of 2:1.

[0103] The C3 agent in the C3 solution consists of p-aminobenzenesulfonic acid and diethylenetriamine in a mass ratio of 1:2.

[0104] The C4 agent in the C4 solution consists of sodium dodecyl sulfonate and sodium diethyldithiocarbamate in a mass ratio of 1:2.

[0105] As can be seen from Table 2, Agent C has the best viscosity-reducing effect on crude oil, which is significantly better than the viscosity-reducing effect of other groups. This shows that the combination of sodium dodecyl sulfonate and diethylenetriamine with a mass ratio of 1:2 has the best viscosity-reducing effect.

[0106] Experiment Example 3: Evaluation of the effect of assisted ovulation

[0107] Measure 200 ml of each of the following solutions: 0.5% sodium dodecyl sulfate solution, 0.5% polyvinylpyrrolidone solution, 0.5% agent D solution, 0.5% agent D1 solution, 0.5% agent D2 solution, 0.5% agent D3 solution, 0.5% agent D4 solution, and 0.5% agent D5 solution. Add each solution to a corresponding 1000 ml beaker. Place the beakers in a constant temperature water bath, stir at 30 rpm, and maintain the temperature at 50°C for 24 hours. Then, measure the total foam volume according to the ASTM D1173-07 standard specification. The evaluation results are shown in Table 3.

[0108] Table 3 Evaluation of the drainage-aiding effects of different agents

[0109]

[0110] Agent D in solution D consists of polyvinylpyrrolidone and sodium dodecyl sulfate in a mass ratio of 1:2.5.

[0111] The D1 agent in the D1 solution consists of polyvinylpyrrolidone and sodium dodecyl sulfate in a mass ratio of 1:1.5.

[0112] The D2 agent in the D2 solution consists of polyvinylpyrrolidone and sodium dodecyl sulfate in a mass ratio of 1:1.

[0113] The D3 agent in the D3 solution consists of polyvinylpyrrolidone and sodium dodecyl sulfate in a mass ratio of 1.5:1.

[0114] The D4 agent in the D4 solution consists of polyvinylpyrrolidone and sodium dodecyl sulfonate in a mass ratio of 1:2.5.

[0115] The D5 agent in the D5 solution consists of sodium diethyldithiocarbamate and sodium dodecyl sulfate in a mass ratio of 1:2.5.

[0116] As can be seen from Table 3, Agent D had the best excretion-aiding effect, which was significantly better than the excretion-aiding effect of other groups. This shows that when polyvinylpyrrolidone and sodium dodecyl sulfate are combined at a mass ratio of 1:2.5, the excretion-aiding effect is the best.

[0117] Experiment Example 4: Evaluation of Temporary Blocking Effect

[0118] Experimental instruments and equipment:

[0119] HA-P100 horizontal flow pump: flow rate 0.1-600 ml / min, pressure 0.1-10 MPa;

[0120] Vacuum dryer: temperature 20-100℃, vacuum degree ≤100Pa;

[0121] Core measuring instrument: temperature 20-100℃, pressure 0.1-12MPa;

[0122] Experimental sample preparation:

[0123] Six standard core samples: diameter × length = 2.5cm × 5cm; two samples each with permeability of 500mdc, 50mdc, and 5mdc.

[0124] Preparation of simulated formation water: Prepare an aqueous solution with a mineralization of 5000 mg / L using sodium chloride:potassium chloride:sodium bicarbonate in a mass ratio of 1:1:1. This is the simulated formation water.

[0125] Experimental process and steps:

[0126] Experimental Example 4-1

[0127] (1) Take one core of each of the above three types of permeability and saturate it with simulated formation water;

[0128] (2) Place the saturated core into a core measuring instrument and keep it at a constant temperature of 25℃ for 30 minutes;

[0129] (3) Displace 10% BCD solution with a horizontal flow pump (B agent:C agent:D agent is mixed in a mass ratio of 6:4:3 to form BCD agent, and then added to water to prepare 10% BCD solution), and record the flow rate through different osmosis intervals;

[0130] (4) Calculate the percentage of flow through different infiltration intervals.

[0131] Experimental Example 4-2

[0132] (1) Saturate one core of each of the above three types of permeability with 10% A solution;

[0133] (2) Place the saturated core into a core measuring instrument and keep it at a constant temperature of 25℃ for 30 minutes;

[0134] (3) Displace 10% BCD solution with a horizontal flow pump (B agent:C agent:D agent is mixed in a mass ratio of 6:4:3 to form BCD agent, and then added to water to prepare 10% BCD solution), and record the flow rate through different osmosis intervals;

[0135] (4) Calculate the percentage of flow through different infiltration intervals.

[0136] The test results are shown in Table 4 below.

[0137] Table 4 Evaluation of the effect of Agent A in temporarily plugging high-permeability layers and tapping potential in secondary high-permeability and low-permeability layers during the unblocking process.

[0138]

[0139] As shown in Table 4, Agent A has a sealing and temporary plugging effect on high-permeability layers (deficient layers), significantly improving the ability of Agents B, C, and D to enter the secondary high-permeability layers and low-permeability layers in sequence, fully tapping the potential of the "target layer", increasing the production increase, and realizing the effective exploitation of low-yield, inefficient, and difficult-to-exploit oil layers in the middle and late stages of oilfield development.

[0140] Experiment Example 5: Evaluation Experiment on Improving the Degree of Reaction

[0141] Experimental Example 5-1

[0142] (1) Measure 200 ml of 0.3% partially hydrolyzed polyacrylamide (HPAM, molecular weight 2000) solution (viscosity at 50℃ is 50 mPa.s) and put it into a beaker. Place the beaker in a constant temperature water bath and keep it at 50℃ for 30 min.

[0143] (2) Add 2 drops of BCD solution to the beaker and observe the reaction diffusion during the droplet falling.

[0144] The diffusion of the droplet upon being added to the beaker and the degree of reaction in the beaker after 15 minutes were observed respectively. The results are as follows: Figure 1 , Figure 2 As shown, through Figure 1 It can be seen that after the BCD solution is added dropwise, the diffusion is slow and the degree of reaction is low. Figure 2 It can be seen that the degree of reaction remained basically unchanged after 15 minutes.

[0145] Experimental Example 5-2

[0146] (1) Measure 200ml of HPAM and Agent A mixture (HPAM accounts for 0.3% and Agent A accounts for 10% in the mixture) and put it into a beaker. Place the beaker in a constant temperature water bath at 50℃ for 30min.

[0147] (2) Add 5 drops of BCD solution to the beaker and observe the reaction diffusion during the droplet falling process.

[0148] The diffusion of the droplet upon being added to the beaker and the degree of reaction in the beaker after 15 minutes were observed respectively. The results are as follows: Figure 3 , Figure 4 As shown, through Figure 3 It can be seen that after the BCD solution is added dropwise, it diffuses rapidly and the degree of reaction is high. Figure 4 It can be seen that after 15 minutes, the diffusion spreads to the entire reaction system, and the degree of diffusion reaches almost 100%.

[0149] pass Figures 1-4 The observation results show that when the oil layer energy-enhancing, unblocking, viscosity-reducing, and drainage-aiding composite integrated agent of the present invention is used for unblocking and production-increasing measures, it releases a large amount of gas by utilizing the energy-enhancing properties of agent A, which plays a dynamic stirring role and greatly improves the reaction degree of the production-increasing agent. This fundamentally solves the technical difficulties of production-increasing agents in "entering the target layer and having a low reaction degree", and maximizes the production-increasing effect.

[0150] Experiment Example 6: Evaluation Experiment of Acid Sensitivity

[0151] Take containers 1-1, 1-2, 2-1, 2-1, 3-1, and 3-2 at room temperature;

[0152] Add 20g of Zhoufu 60-46 core powder to container 1-1, then add 100ml of 10% hydrochloric acid solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0153] Add 20g of Zhoufu 60-46 core powder to container 1-2, then add 100ml of 10% B solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0154] Add 20g of Zhou 602-7 core powder to container 2-1, then add 100ml of 10% hydrochloric acid solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0155] Add 20g of Zhou 602-7 core powder to container 2-2, then add 100ml of 10% B solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0156] Add 20g of Zhao 33-Ping 28 core powder to container 3-1, then add 100ml of 10% hydrochloric acid solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0157] Add 20g of Zhao 33-Ping 28 core powder to container 3-2, then add 100ml of 10% B solution. After the reaction is complete, measure the pH value and observe the precipitation of the reaction solution.

[0158] The results are shown in Table 5.

[0159] Table 5. Evaluation and Analysis of Acid Sensitivity Effect

[0160]

[0161] As shown in Table 5, when Agent B is used to enhance production, even in reservoirs with high iron-rich chlorite content (greater than 2.5%), it will not produce iron ion precipitation, will not cause acid-sensitive damage (blockage) to the reservoir, and will improve the production enhancement effect of the measure.

[0162] Experimental Example 7: Conventional Vertical Well

[0163] After indoor analysis and evaluation, well Nan 208-286 was found to have low formation energy and severe depletion. Incompatible materials were introduced into the reservoir, resulting in severe blockage by inorganic scale. Blockage by organic matter such as asphalt, gum, and wax was the main cause of the decline in reservoir energy. The production enhancement measures using the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid prepared in Example 2 of this application can achieve significant production enhancement effects, as shown in Table 6 below.

[0164] Table 6. Analysis of the Production Enhancement Effect of Integrated Energy-Enhancing, Unblocking, Viscosity-Reducing, and Drainage-Assisting Agents on Conventional Vertical Wells

[0165]

[0166] Example 8 Horizontal Well

[0167] After indoor analysis and evaluation, well 10H92-A48 was found to have low reservoir permeability, low formation energy, severe depletion, severe inorganic scale blockage, thick oil, and blockage by organic matter such as asphalt, gum, and wax, which were the main reasons for the decline in reservoir energy. The production enhancement measures using the integrated oil layer energy enhancement, unblocking, viscosity reduction, and drainage aid prepared in Example 2 of this application can achieve significant production enhancement effects, as shown in Table 7 below.

[0168] Table 7. Analysis of the Production Enhancement Effect of Integrated Energy-Enhancing, Unblocking, Viscosity-Reducing, and Drainage-Assisting Agents on Horizontal Wells

[0169]

[0170] Example 9: Well Opening

[0171] After indoor analysis and evaluation, it was found that the formation energy of well Nan 272-P254 was low, the formation was severely depleted, the formation was intermittent, and the fluid supply capacity was poor. These were the main reasons for the decline in reservoir energy. The production enhancement measures using the integrated oil layer energy enhancement, unblocking, viscosity reduction and drainage aid prepared in Example 2 of this application can achieve significant production enhancement effects, as shown in Table 8 below.

[0172] Table 8. Analysis of the Production Enhancement Effect of Integrated Energy-Enhancing, Unblocking, Viscosity-Reducing, and Drainage-Assisting Agents on Intermittent Wells

[0173]

[0174] In this invention, the term "some embodiments" means that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiments. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments. Moreover, those skilled in the art can combine and integrate the different embodiments and features described in this specification without contradiction.

[0175] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. The application method of a composite agent for enhancing reservoir capacity, unblocking, reducing viscosity, and aiding drainage, characterized in that: The integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid comprises: Agent A: The components are urea, urease and sodium bicarbonate, with a mass ratio of 5:1:4; Agent B: The components are p-aminobenzenesulfonic acid, ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane, with a mass ratio of 8:1:1; Agent C: The components are sodium dodecyl sulfonate and diethylenetriamine, with a mass ratio of 1:2; Agent D: The components are polyvinylpyrrolidone and sodium dodecyl sulfate, with a mass ratio of 1:2.5; The mass ratio of agent A, agent B, agent C, and agent D is (3-4):(3-4):(1.5-2.5):(1.5-2). Agent A is prepared with water to form a 10% solution, i.e., Solution A, for later use; Agent B is prepared with water to form a 12% solution, i.e. Solution B, for later use; Agent C is prepared with water to form a 5% solution, i.e. Solution C, for later use; Agent D is prepared with water to form a 5% solution, i.e. Solution D, for later use. Application methods include: S1: Inject solution A into the oil layer; S2: After solution A is injected, a mixture of solutions B and C is injected into the oil layer. The amount of solution B used in the mixture is 50% of the total amount of solution B. S3: Continue to inject the mixture of solution B and solution D, in which the amount of solution B used is 50% of the total amount of solution B.

2. The application method of the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid according to claim 1, characterized in that, include: Preparation of Agent A: First, add urea and sodium bicarbonate to the reaction vessel and stir at 23-27℃ for 30-45 minutes at a stirring speed of 30-60 r / min; then add urease to the reaction vessel and continue stirring at 23-27℃ for 45-60 minutes to obtain Agent A. Preparation of Agent B: First, add p-aminobenzenesulfonic acid to the reaction vessel and stir at 23-27℃ for 30-45 minutes at a stirring speed of 30-60 r / min; then add ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane to the reaction vessel and continue stirring at 23-27℃ for 45-60 minutes to obtain Agent B. Preparation of Agent C: First, add sodium dodecyl sulfonate to the reaction vessel and stir at 45-55℃ for 30-45 min at a stirring speed of 30-60 r / min; then add diethylenetriamine to the reaction vessel and continue stirring at 45-55℃ for 45-60 min, cool to room temperature to obtain Agent C; Preparation of Agent D: First, add polyvinylpyrrolidone to the reaction vessel and stir at 45-55℃ for 30-45 min at a stirring speed of 30-60 r / min; then add sodium dodecyl sulfate to the reaction vessel and continue stirring at 45-55℃ for 45-60 min, and cool to room temperature to obtain Agent D.

3. The application method of the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid according to claim 2, characterized in that, include: Preparation of Agent A: First, add urea and sodium bicarbonate to the reaction vessel and stir at 25°C for 30 minutes at a stirring speed of 45 r / min; then add urease to the reaction vessel and continue stirring at 25°C for 45 minutes to obtain Agent A. Preparation of Agent B: First, add p-aminobenzenesulfonic acid to the reaction vessel and stir at 25°C for 30 min at a stirring speed of 45 r / min; then add ethylenediaminetetramethylenephosphonic acid and polydimethylsiloxane to the reaction vessel and continue stirring at 25°C for 45 min to obtain Agent B. Preparation of Agent C: First, sodium dodecyl sulfonate was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 60 r / min; then, diethylenetriamine was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent C was obtained. Preparation of Agent D: First, polyvinylpyrrolidone was added to the reaction vessel and stirred at 50°C for 30 min at a stirring speed of 45 r / min; then sodium dodecyl sulfate was added to the reaction vessel and stirred at 50°C for another 45 min. After cooling to room temperature, Agent D was obtained.

4. The application method of the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid according to claim 1, characterized in that, The mass ratio of the applied agents A, B, C, and D is 3.5:3:2:1.

5.

5. The application method of the integrated oil reservoir energy enhancement, unblocking, viscosity reduction, and drainage aid according to claim 1, characterized in that, The preparation method of solution A includes the following steps: adding some water to a mixing tank, maintaining a constant temperature of 25-28℃, adding agent A to the mixing tank at an addition rate of 45-55 kg / min, adding the remaining water to make the concentration of agent A 10%, maintaining a constant temperature of 25-28℃, stirring at 45-65 r / min, and thus preparing solution A. The preparation method of solution B includes the following steps: adding some water to a mixing tank, maintaining a constant temperature of 25-30℃, adding agent B to the mixing tank at an addition rate of 45-55 kg / min, adding the remaining water to make the concentration of agent B 12%, maintaining a constant temperature of 25-30℃, stirring at 45-65 r / min, and thus preparing solution B. The preparation method of solution C includes the following steps: adding some water to a mixing tank, maintaining the temperature at 25-30℃, adding agent C to the mixing tank at an addition rate of 15-25 kg / min, adding water to make the concentration of agent C 5%, maintaining the temperature at 25-30℃, stirring at 45-65 r / min, and thus preparing solution C. The preparation method of solution D includes the following steps: adding some water to a mixing tank, maintaining a constant temperature of 25-30℃, adding agent D to the mixing tank at an addition rate of 10-15 kg / min, adding water to make the concentration of agent D 5%, maintaining a constant temperature of 25-30℃, and stirring at 45-65 r / min to prepare solution D.

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