阅读说明：本技术 一种适用于sagd微压裂的封堵剂及其制备方法 (Plugging agent suitable for SAGD micro-fracturing and preparation method thereof ) 是由 刘亮亮 赵玲莉 柯迪昕 李嘉玮 邵炜 李国安 张胜 贾紫轩 王海峰 高伟 张乐 于 2021-10-11 设计创作，主要内容包括：本发明提供了一种适用于SAGD微压裂的封堵剂及其制备方法,涉及封堵剂制备技术领域。本发明的封堵剂是利用磺化聚丙烯酰胺、交联剂、稳定剂、促进剂、抗老剂、增强剂和水按一定配比制备而成。本发明适用于SAGD微压裂的封堵剂具有耐高温及可反复承压的性能,在封堵剂成胶或凝固后,能够有效封堵气窜通道,建立一个相对密闭的提压空间,为微压裂措施提供提压保障,有效提升压力,提高微压裂效果。(The invention provides a plugging agent suitable for SAGD micro fracturing and a preparation method thereof, and relates to the technical field of plugging agent preparation. The blocking agent is prepared from sulfonated polyacrylamide, a cross-linking agent, a stabilizer, an accelerator, an anti-aging agent, a reinforcing agent and water according to a certain proportion. The plugging agent suitable for SAGD micro-fracturing has the performances of high temperature resistance and repeated pressure bearing, and can effectively plug a gas channeling channel after the plugging agent is gelatinized or solidified, so that a relatively closed pressure boosting space is established, a pressure boosting guarantee is provided for micro-fracturing measures, the pressure is effectively boosted, and the micro-fracturing effect is improved.)

1. The blocking agent suitable for SAGD micro fracturing is characterized by comprising the following raw materials in percentage by weight:

sulfonated polyacrylamide: 0.3-0.5%;

a crosslinking agent: 0.2-0.45%;

a stabilizer: 0.1-0.25%;

accelerator (b): 0.1-0.6%;

anti-aging agent: 0.01-0.2%;

reinforcing agent: 0 to 7 percent.

The balance being water.

2. The plugging agent suitable for SAGD micro fracturing of claim 1, wherein the sulfonated polyacrylamide is polymerized from methyl propane sulfonic acid and acrylamide, the molecular weight is 500-2500 ten thousand, and the degree of hydrolysis is 10-22%.

3. The plugging agent suitable for SAGD micro fracturing of claim 1, wherein the cross-linking agent is one or more of chromium formate, chromium acetate, chromium amino acid, formaldehyde, chromium nicotinate, hexamethylenetetramine, paraformaldehyde.

4. The plugging agent suitable for SAGD microfracture of claim 1, wherein the stabilizer is one or more of ammonium chloride, sodium chloride.

5. The plugging agent suitable for SAGD microfracture of claim 1, wherein the accelerator is one or more of urea, xylenol, resorcinol, hydroquinone.

6. The plugging agent suitable for SAGD micro fracturing of claim 1, wherein the anti-aging agent is one or more of thiourea, fumed silica, granulated blast furnace slag, silica fume.

7. The plugging agent suitable for SAGD micro-fracturing of claim 1, wherein said reinforcing agent is one or more of nano-based clay, larch tannin extract, bayberry tannin extract.

8. A preparation method of the plugging agent suitable for SAGD micro fracturing of any one of claims 1 to 7 is characterized by comprising the following steps:

(1) weighing the raw materials according to the weight percentage;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15-20 minutes until the sulfonated polyacrylamide mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the anti-aging agent, the reinforcing agent, the accelerator and the stabilizer with water to prepare anti-aging agent mother liquor, reinforcing agent mother liquor, accelerator mother liquor and stabilizer mother liquor with mass concentrations of 4-6%, uniformly stirring and standing for later use;

(4) mixing a cross-linking agent with water to prepare a cross-linking agent mother solution with the mass concentration of 8-12%, uniformly stirring, and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a drying oven at 100-150 ℃ for 60-120 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

Technical Field

The invention relates to the technical field of preparation of plugging agents, in particular to a plugging agent suitable for SAGD micro fracturing and a preparation method thereof.

Background

SAGD is called steam for short and assists gravity drainage, it is a steam from a straight well or a horizontal well above the horizontal production well near the bottom of the oil reservoir to inject into the oil reservoir, crude oil and steam condensate heated produce oil recovery method from the horizontal well at the bottom of the oil reservoir, have high oil recovery ability, high oil-gas ratio, higher final recovery ratio and reduce the interwell interference, avoid too early interwell channeling.

The micro-fracturing measure is implemented on the SAGD well, so that the expansion volume of a steam cavity can be effectively improved, an oil drainage channel is increased, the production time is reduced, and steam can be saved. However, wells for general SAGD micro fracturing are new wells which are not put into production, micro fracturing is carried out in the original stratum energy state, when micro fracturing measures are carried out, because stratum energy is sufficient, micro fracturing is relatively easy, at present, micro fracturing measures are still required to be carried out on wells with partial put into production, and because the stratum energy is lacked after production, a channeling channel exists in the stratum, effective pressure raising cannot be carried out when fracturing reconstruction is directly carried out, so that micro fracturing cannot be carried out normally or the micro fracturing effect is poor.

Disclosure of Invention

In view of the above, the invention provides a plugging agent suitable for SAGD micro-fracturing, which has high temperature resistance and repeated pressure bearing performance, and after the plugging agent is gelled or solidified, the plugging agent can effectively plug a gas channeling channel, establish a relatively closed pressure lifting space, provide pressure lifting guarantee for micro-fracturing measures, effectively lift pressure, and improve the micro-fracturing effect.

The invention relates to a plugging agent suitable for SAGD micro-fracturing, which comprises the following raw materials in percentage by weight:

sulfonated polyacrylamide: 0.3-0.5%;

a crosslinking agent: 0.2-0.45%;

a stabilizer: 0.1-0.25%;

accelerator (b): 0.1-0.6%;

anti-aging agent: 0.01-0.2%;

reinforcing agent: 0 to 7 percent.

The balance being water.

Preferably, the sulfonated polyacrylamide is polymerized by methyl propanesulfonic acid and acrylamide, the molecular weight is 500-2500 ten thousand, and the hydrolysis degree is 10-22%.

Preferably, the cross-linking agent is one or more of chromium formate, chromium acetate, chromium amino acid, formaldehyde, chromium nicotinate, hexamethylenetetramine and paraformaldehyde.

Preferably, the stabilizer is one or more of ammonium chloride and sodium chloride.

Preferably, the accelerator is one or more of urea, xylenol, resorcinol and hydroquinone.

Preferably, the anti-aging agent is one or more of thiourea, fumed silica, granulated blast furnace slag and silicon micropowder.

Preferably, the enhancer is one or more of nano-clay, larch tannin extract and bayberry tannin extract.

Another object of the present invention is to provide a method for preparing a plugging agent for SAGD micro fracturing, comprising the steps of:

(1) weighing the raw materials according to the weight percentage;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15-20 minutes until the sulfonated polyacrylamide mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the anti-aging agent, the reinforcing agent, the accelerator and the stabilizer with water to prepare anti-aging agent mother liquor, reinforcing agent mother liquor, accelerator mother liquor and stabilizer mother liquor with mass concentrations of 4-6%, uniformly stirring and standing for later use;

(4) mixing a cross-linking agent with water to prepare a cross-linking agent mother solution with the mass concentration of 8-12%, uniformly stirring, and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a drying oven at 100-150 ℃ for 60-120 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The conventional heavy oil well old well cannot be subjected to SAGD micro-fracturing measures due to the fact that a channeling channel exists, after the blocking agent blocks the stratum channeling channel, the blocking barrier is built after the blocking agent is gelatinized or solidified, the channeling channel is blocked, pressure raising micro-fracturing measures can be effectively built, and the old well can be changed into effective micro-fracturing measures from the original condition that pressure cannot be built. The invention adopts a plugging agent or a modified plugging agent thereof, and the plugging agent has certain temperature resistance and pressure bearing capacity through reasonable sectional plugging system design, meets the pressure increasing requirement of SAGD micro fracturing, and ensures the measure effect of the SAGD micro fracturing.

Compared with the prior art, the invention has the following beneficial effects:

the blocking agent disclosed by the invention is adjustable in strength and section design, can meet flexible adjustment under various construction requirements, breaks through pressure of 3-20 MPa, has extremely high bearing capacity and high construction success rate, and can meet the requirements of micro-fracturing measures under various pressure-raising backgrounds by adjusting the strength. The temperature resistance is strong and adjustable, and the design of temperature resistance adjustment (temperature resistance of 120-160 ℃) can be carried out according to different temperature conditions.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1:

a plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.3 percent;

crosslinking agent chromium acetate: 0.2 percent;

stabilizer ammonium chloride: 0.2 percent;

accelerator urea: 0.1 percent;

age resister fumed silica: 0.1 percent;

reinforcing agent nano clay: 1 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the age resister weather-method white carbon black, the reinforcing agent nano-clay, the accelerating agent urea and the stabilizing agent ammonium chloride with water to prepare an age resister weather-method white carbon black mother liquor, a reinforcing agent nano-clay mother liquor, an accelerating agent urea mother liquor and a stabilizing agent ammonium chloride mother liquor with mass concentrations of 5%, uniformly stirring and standing for later use;

(4) mixing a crosslinking agent chromium acetate with water to prepare a crosslinking agent chromium acetate mother liquor with the mass concentration of 10%, uniformly stirring, and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 120 ℃ oven for 90 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the plugging agent is 120-130 ℃, wherein the temperature resistance is stable for 3 months at 120 ℃ and stable for 1 month at 130 ℃. The breakthrough pressure is more than 6 MPa.

Example 2

A plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.35 percent;

crosslinking agent chromium acetate: 0.22 percent;

stabilizer ammonium chloride: 0.25 percent;

accelerator urea: 0.1 percent;

age resister fumed silica: 0.01 percent;

anti-aging agent granulated blast furnace slag: 0.09%;

reinforcing agent nano clay: 1 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the age resister weather white carbon black, the age resister granulated blast furnace slag, the reinforcing agent nano-clay, the accelerator urea and the stabilizer ammonium chloride with water to prepare an age resister weather white carbon black mother liquor, an age resister granulated blast furnace slag mother liquor, a reinforcing agent nano-clay mother liquor, an accelerator urea mother liquor and a stabilizer ammonium chloride mother liquor with mass concentrations of 5%, uniformly stirring and standing for later use;

(4) mixing a crosslinking agent chromium acetate with water to prepare a crosslinking agent chromium acetate mother liquor with the mass concentration of 10%, uniformly stirring, and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 120 ℃ oven for 60 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the plugging agent is 120-130 ℃, wherein the temperature resistance is stable for 3 months at 120 ℃ and stable for 1 month at 130 ℃. The breakthrough pressure is more than 10 MPa.

Example 3

A plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.4 percent;

crosslinking agent chromium acetate: 0.2 percent;

crosslinking agent chromium formate: 0.05 percent;

stabilizer ammonium chloride: 0.25 percent;

accelerator urea: 0.1 percent;

age resister fumed silica: 0.1 percent;

intensifier larch tannin extract: 5 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the age resister weather-process white carbon black, the reinforcing agent larch tannin extract, the accelerant urea and the stabilizing agent ammonium chloride with water to prepare an age resister weather-process white carbon black mother liquor, a reinforcing agent larch tannin extract mother liquor, an accelerant urea mother liquor and a stabilizing agent ammonium chloride mother liquor with mass concentrations of 5%, uniformly stirring and standing for later use;

(4) respectively mixing a crosslinking agent chromium acetate and a crosslinking agent chromium formate with water to prepare a crosslinking agent chromium acetate mother liquor and a crosslinking agent chromium formate mother liquor with mass concentrations, uniformly stirring, and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 120 ℃ oven for 90 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the plugging agent is 120-140 ℃, wherein the temperature resistance is stable for 3 months at 120 ℃ and stable for 1 month at 140 ℃. The breakthrough pressure is more than 20 MPa.

Example 4

A plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.3 percent;

crosslinker hexamethylenetetramine: 0.29 percent;

cross-linking agent formaldehyde: 0.01 percent;

stabilizer ammonium chloride: 0.1 percent;

accelerator hydroquinone: 0.3 percent;

accelerator urea: 0.1 percent;

age resister fumed silica: 0.01 percent;

anti-aging agent thiourea: 0.09%;

reinforcing agent nano clay: 5 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) mixing the anti-aging agent thiourea, the anti-aging agent fumed silica, the reinforcing agent nano-clay, the reinforcing agent hydroquinone, the reinforcing agent urea and the stabilizing agent ammonium chloride with water respectively to prepare anti-aging agent fumed silica mother liquor, reinforcing agent nano-clay mother liquor, reinforcing agent hydroquinone mother liquor, reinforcing agent urea mother liquor and stabilizing agent ammonium chloride mother liquor with mass concentration of 5%, uniformly stirring and standing for later use;

(4) respectively mixing a crosslinking agent hexamethylene tetramine and a crosslinking agent formaldehyde with water to prepare a crosslinking agent hexamethylene tetramine mother liquor and a crosslinking agent formaldehyde mother liquor with mass concentrations of 10%, uniformly stirring and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 140 ℃ oven for 120 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the blocking agent is 140-160 ℃, wherein the blocking agent is stable for 3 months at 140 ℃ and stable for 1 month at 160 ℃. The breakthrough pressure is more than 3 MPa.

Example 5

A plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.4 percent;

crosslinker hexamethylenetetramine: 0.37 percent;

cross-linking agent formaldehyde: 0.03 percent;

stabilizer ammonium chloride: 0.1 percent;

accelerator urea: 0.05 percent;

accelerator resorcinol: 0.4 percent;

anti-aging agent thiourea: 0.09%;

age resister fumed silica: 0.01 percent;

intensifier bayberry tannin extract: 5 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the anti-aging agent weather-process white carbon black, the anti-aging agent thiourea, the reinforcing agent bayberry tannin extract, the accelerator urea, the accelerator resorcinol and the stabilizer ammonium chloride with water to prepare an anti-aging agent weather-process white carbon black mother liquor, an anti-aging agent thiourea mother liquor, a reinforcing agent bayberry tannin extract mother liquor, an accelerator resorcinol mother liquor, an accelerator urea mother liquor and a stabilizer ammonium chloride mother liquor with mass concentrations of 5%, uniformly stirring and standing for later use;

(4) respectively mixing a cross-linking agent formaldehyde and a cross-linking agent hexamethylene tetramine with water to prepare a cross-linking agent hexamethylene tetramine mother liquor and a cross-linking agent formaldehyde mother liquor with mass concentrations of 10%, uniformly stirring and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 140 ℃ oven for 100 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the blocking agent is 140-160 ℃, wherein the blocking agent is stable for 3 months at 140 ℃ and stable for 1 month at 160 ℃. The breakthrough pressure is more than 5 MPa.

Example 6

A plugging agent suitable for SAGD micro fracturing comprises the following raw materials in percentage by mass:

sulfonated polyacrylamide: 0.5 percent;

crosslinker hexamethylenetetramine: 0.37 percent;

cross-linking agent formaldehyde: 0.03 percent;

stabilizer ammonium chloride: 0.1 percent;

accelerator resorcinol: 0.5 percent;

anti-aging agent thiourea: 0.19 percent;

age resister fumed silica: 0.01 percent;

intensifier bayberry tannin extract: 2 percent;

reinforcing agent nano clay: 5 percent;

the balance being water.

The preparation method comprises the following steps:

(1) weighing the raw materials according to the proportion;

(2) mixing sulfonated polyacrylamide with water to obtain a sulfonated polyacrylamide mother liquor with the mass concentration of 1%, stirring for 15 minutes until the mother liquor is uniform, and standing for 1 hour until the sulfonated polyacrylamide is fully swelled;

(3) respectively mixing the anti-aging agent weather-process white carbon black, the anti-aging agent thiourea, the reinforcing agent bayberry tannin extract, the reinforcing agent nano-clay, the reinforcing agent resorcinol and the stabilizing agent ammonium chloride with water to prepare anti-aging agent weather-process white carbon black mother liquor, anti-aging agent thiourea mother liquor, the reinforcing agent resorcinol mother liquor, the reinforcing agent bayberry tannin extract mother liquor, the reinforcing agent nano-clay mother liquor and the stabilizing agent ammonium chloride mother liquor with the mass concentration of 5%, uniformly stirring and standing for later use;

(4) respectively mixing a cross-linking agent formaldehyde and a cross-linking agent hexamethylene tetramine with water to prepare a cross-linking agent hexamethylene tetramine mother liquor and a cross-linking agent formaldehyde mother liquor with mass concentrations of 10%, uniformly stirring and standing for later use;

(5) and (3) mixing and stirring the mother liquor prepared in the steps (2) to (4) for 5 minutes until the mother liquor is uniform, adding the rest water, continuing stirring for 5 minutes, and after the mixed liquor is uniformly stirred, putting the mixed liquor into a 140 ℃ oven for 90 minutes to obtain the plugging agent suitable for SAGD micro-fracturing.

The temperature resistance of the blocking agent is 140-160 ℃, wherein the blocking agent is stable for 3 months at 140 ℃ and stable for 2 months at 160 ℃. The breakthrough pressure is more than 8 MPa.

The plugging agent suitable for SAGD new well micro-fracturing and the plugging agent with the formation temperature of about 100 ℃ are generally adopted as comparative examples, a component raw material manufacturer of the plugging agent is Xinjiang Clay, Milli chemical industry, Limited liability company, and 6 plugging agents with different proportions are selected as the comparative examples:

comparative example 1

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: anionic polymer: 0.5 percent; crosslinking agent potassium dichromate: 0.15%, reducing agent anhydrous sodium sulfite: 0.18 percent and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

Comparative example 2

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: anionic polymer: 0.45 percent; crosslinking agent potassium dichromate: 0.22%, reducing agent anhydrous sodium sulfite: 0.25 percent and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

Comparative example 3

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: polyacrylamide: 0.35 percent; crosslinker hexamethylenetetramine: 0.25 percent; accelerator resorcinol: 0.05 percent; stabilizer ammonium chloride: 0.12 percent; anti-aging agent thiourea: 0.05% and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

Comparative example 4

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: polyacrylamide: 0.45 percent; crosslinker hexamethylenetetramine: 0.3 percent; 0.05% of cross-linking agent formaldehyde; accelerator resorcinol: 0.05 percent; regulator phosphoric acid 0.012%; anti-aging agent thiourea: 0.05% and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

Comparative example 5

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: sulfonated polyacrylamide: 0.35 percent; crosslinking agent chromium acetate: 0.2 percent; stabilizer ammonium chloride: 0.12 percent; anti-aging agent granulated blast furnace slag: 0.05% and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

Comparative example 6

A micro-fracturing plugging agent suitable for a new well which is not put into production in SAGD comprises the following raw materials in percentage by weight: sulfonated polyacrylamide: 0.35 percent; crosslinking agent chromium acetate: 0.25 percent; stabilizer ammonium chloride: 0.2 percent; anti-aging agent granulated blast furnace slag: 0.07% and the balance of water.

Weighing the raw materials, adding the raw materials into water, and uniformly stirring to obtain the plugging agent.

The plugging agent prepared in example 1 and suitable for SAGD micro-fracturing was applied to Xinjiang oil field heavy oil company for 2 wells (HWT98003, HWT 98016). The daily oil production of the HWT98003 well is increased by 5.6t compared with that before the measure, and is increased by 5.9t compared with that of an adjacent well of the same reservoir, and the accumulated oil is increased by 706 t. The daily oil production of the HWT98016 well is increased by 3t compared with that before the measure, the daily oil production is increased by 21.2t compared with that before the measure, and the oil production is increased by 348t cumulatively.

Performance testing

The blocking agents prepared in examples 1 to 6 were subjected to viscosity and breakthrough pressure measurement according to the method in SY/T5590-2004 "method for evaluating Performance of Profile control agent"; the plugging agents prepared in examples 1-6 were subjected to core plugging rate performance detection according to the method in SY/T5107-2016 Water-based fracturing fluid performance evaluation method, and the results are shown in Table 1.

TABLE 1

Comparative blocking agents were tested as described above and the results are shown in table 2:

TABLE 2

The artificial rock core simulation plugging condition of the plugging agent is performed in the embodiments 1-6, the artificial sandstone rock core is generally composed of quartz sand with different particle sizes, a small amount of dispersed clay and a cementing material, the sand is fully mixed and then is heated and mixed with the cementing material to be ground, rubbed and stirred, the sand and the cementing material are uniformly mixed as far as possible, a thin layer of colloidal film is formed on the sand, the sand with the colloidal film is filled into a mold, compacted and cemented, and finally the mold is heated and shaped to form the artificial rock core. In examples 1 to 6, the main experimental material for the performance measurement of the core plugging rate is the core, the core is divided into a natural core and an artificial core, and due to the limitation of the source and the limitation of the quantity of the natural core, most of experiments adopt the artificial core, the artificial core simulation experiment is performed on the plugging agent of examples 1 to 6 according to the methods in SY/T5107-2016 (water-based fracturing fluid performance evaluation method) and SY/T5590-2004 (profile control agent performance evaluation method), and the performance measurement of the breakthrough pressure and the core plugging rate is performed, and the results are shown in table 3:

TABLE 3

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.