CN106279509B - Oily double suction resin and preparation method and application are met suitable for the chance water of oil-well cement - Google Patents

Abstract

The invention discloses a water-meets-oil double-absorbing resin suitable for oil well cement and its preparation method and application. The body, the oil phase cross-linking agent, the emulsifier, the co-emulsifier and the initiator are sequentially added into the reaction vessel, stirred and mixed evenly to form a single-phase colorless transparent double continuous microemulsion, and then carry out the polymerization reaction. The synthesis process of the invention is stable, the microemulsion can be kept from delamination during the polymerization process, and the synthesis time is short; the synthesized water-meeting double-absorbent resin has a fast liquid absorption rate. When the downhole cement sheath of an oil well is damaged and micro-cracks occur, the double-absorbent resin that encounters water and oil meets the water flow or oil flow through the micro-cracks and can quickly absorb water and oil to expand, forming a physical seal at the place where the cement sheath is damaged.

Description

Water and oil double-absorbent resin suitable for oil well cement, preparation method and application

technical field

The present invention relates to a method for preparing a water-meets-oil double-absorbent resin, and also relates to a water-meets-oil double-absorbent resin prepared by the preparation method, and the water-meets-oil double-absorbent resin used as a water-oil-absorbing swelling component in oil well cement in the application. The invention belongs to the fields of oil and gas well cementing and oil field chemistry.

Background technique

The cement sheath of oil and gas wells is subjected to complex downhole conditions such as high temperature and high pressure. After it is put into production, it will inevitably face various complex operations such as well testing, testing and production. The channel of formation fluid channeling causes the failure of interlayer isolation.

The water-absorbing and oil-absorbing expansion resin is added to the cement as an additive. When micro-cracks or micro-annulus are formed inside the cement stone, whether formation water or formation oil flows into the micro-cracks or micro-annulus, the micro-cracks or micro-annulus The water- and oil-absorbing double-absorbent resin will absorb water or oil and swell. The expanded water-absorbing and oil-absorbing resin has a certain strength and can block micro-cracks or micro-annulus, forming a physical plug in the cement failure layer to prevent formation fluid channeling. Therefore, the development of oil well cement that can realize the early diagnosis of the internal damage of the cement sheath and automatically repair and heal it—especially the workover problem of thin oil-water interlayer that cannot be well solved by the current workover technology, is of great help to improve the complex conditions of the cement sheath. long-term stability is of great importance.

Chinese patent CN102887978A prepared a cross-linked cassava starch type super absorbent and oil-absorbing resin, and Chinese patent CN102603978A prepared a cellulose-based water-absorbing and oil-absorbing material, but tapioca starch and cellulose have poor thermal stability under high temperature conditions and are easy to degrade , not suitable for high temperature environment of oil well cement; Chinese patent CN102850483A uses emulsion copolymerization to prepare water-absorbing oil-absorbing bifunctional resin, but the preparation time of this method is long, which is not conducive to industrial production, and the water-absorbing component in this material is not continuous and cannot be realized Rapid water absorption and expansion cannot achieve rapid plugging of micro-fractures in the cement sheath. The double continuous microemulsion system is a thermodynamically stable system, which can be polymerized at a higher temperature and shorten the synthesis time; in addition, the water-absorbing and oil-absorbing resins prepared by the double-continuous microemulsion method have both water-absorbing and oil-swelling components. It is a continuous structure, and the resin is porous inside, which can achieve the purpose of rapid water and oil absorption.

Contents of the invention

The object of the present invention is to provide a kind of water and oil double absorption resin suitable for oil well cement, its preparation method and application.

In order to achieve the above object, according to the present invention, a kind of water and oil double absorption resin is proposed, including distilled water, water phase monomer, water phase crosslinking agent, oil phase monomer, oil phase crosslinking agent, emulsifier, co-emulsifier, initiator The amount of water phase monomer added is 12.5% to 20% of the mass of distilled water, the amount of water phase crosslinking agent added is 5% to 15% of the mass of water phase monomer, and the amount of oil phase monomer added is the same as that of distilled water and water phase. The mass ratio of the total mass of the body is 1:1, the amount of the oil phase crosslinking agent is 0.3% to 1% of the mass of the oil phase monomer, and the amount of the initiator is 1% to 1% of the sum of the mass of the water phase monomer and the oil phase monomer 4%, the amount of emulsifier added is 15% to 20% of the mass sum of distilled water and water phase monomers, and the amount of co-emulsifier added is 300% to 400% of the mass of emulsifier.

Preferably, the water phase monomer is acrylamide, the water phase crosslinking agent is N, N-methylenebisacrylamide, and the oil phase monomer is methyl methacrylate and lauryl methacrylate The mixture, the mass ratio of methyl methacrylate and lauryl methacrylate is (20～100): 100, the oil phase crosslinking agent is divinylbenzene, and the emulsifier is sodium lauryl sulfate , the co-emulsifier is n-butanol, and the initiator is azobisisobutyronitrile.

Preferably, it is prepared by the double continuous microemulsion method, that is, in the preparation process of the double continuous microemulsion polymerization method, the distilled water, the water phase monomer, the water phase crosslinking agent, the oil phase monomer, the oil phase crosslinking agent, the emulsifier , co-emulsifier and initiator are sequentially added into the reaction vessel, stirred and mixed evenly to form a single-phase colorless transparent double continuous microemulsion, and then carry out polymerization reaction.

The present invention also provides a preparation method for the above-mentioned water-meets-oil double-absorbent resin, wherein distilled water, water phase monomers, water phase crosslinking agents, oil phase monomers, oil phase crosslinking agents, emulsifiers, co-emulsifiers, and initiators are sequentially Add it into the reaction vessel, discharge the oxygen in the reaction vessel, stir and mix it at a speed of 400-600 rpm to form a single-phase colorless transparent double continuous microemulsion, react statically in a water bath at 40-80°C, and the obtained product is dried After being pulverized, a water-meets-oil double-absorbent resin is obtained.

Preferably, the stirring speed is 500 rpm.

Preferably, the temperature of the water bath is 60° C., and the static reaction is performed for 3 hours.

Preferably, the drying is at 80° C. for 24 hours.

The present invention further provides the application of the above-mentioned water-meets-oil double-absorbent resin as a water-absorbing and oil-absorbing swelling component in oil well cement.

The preparation method of the present invention utilizes a double continuous microemulsion as a template. In this microemulsion, the water phase and the oil phase are continuous, and the water phase polymerized monomer and the oil phase polymerized monomer are respectively added into the water phase and the oil phase. , a polymerization reaction occurs under the action of an initiator to obtain a water-in-oil double-absorbent resin with a bicontinuous structure, that is, the water-swellable component and the oil-swellable component in the water-in-oil double-absorbent resin are continuous Structure, and the resin is porous inside, so it can prevent the resin from not absorbing water or oil, and can achieve the purpose of rapid water and oil absorption.

The synthesis process of the invention is stable, the microemulsion can be kept from delamination during the polymerization process, and the synthesis time is short; the synthesized water-meeting double-absorbent resin has a fast liquid absorption rate. The water-meets-oil double-absorbent resin prepared by the preparation method of the present invention is added to the oil well cement, and when the downhole cement sheath of the oil well is damaged, the water-meets-oil double-absorbent resin can absorb oil or It absorbs water and swells, forming a physical seal at the place where the cement sheath is damaged, sealing the cracks, and preventing fluid channeling between different layers in the well. In the application of water and oil double absorption resin in oil well cement, the liquid absorption ratio of the resin is required to be between 5 and 6. If the resin absorption rate is too low, the resin cannot effectively seal the crack after the resin absorbs liquid expansion; if the resin absorption rate is too high, the expansion force generated by the resin absorption expansion is too large, which may damage the integrity of the cement stone.

A method for measuring the liquid absorption multiple of a water-meets-oil double-absorbent resin suitable for oil well cement according to the present invention is as follows:

Weigh a certain amount of water-in-oil double-absorbent resin powder, record it as W1, put it into a white non-woven bag, weigh the total mass of the resin and the bag, record it as W2, and then put it into a beaker filled with distilled water or toluene In the process, considering the downhole temperature, the liquid absorption test was carried out at 75°C, and the non-woven bag was taken out every 5 minutes, and hung until there was basically no liquid drop, and the total mass of the non-woven bag and the resin after liquid absorption was weighed, recorded as W3, calculate the liquid absorption rate of the water-in-oil double-absorbent resin, the formula is: liquid absorption rate (g/g)=(W3-W2)/W1.

A method for measuring the liquid absorption rate of a water-meets-oil double-absorbent resin suitable for oil well cement according to the present invention is as follows:

The liquid absorption rate refers to the ratio of the liquid absorption rate (W4) and the saturated liquid absorption rate (W5) at a given time. In order to realize rapid liquid absorption expansion, the given time in the present invention is 10 minutes. Liquid absorption rate = W4/W5.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

Fig. 1 is the photogram of water encountering oil double absorption resin, wherein A is the resin obtained in embodiment 2, and B is the resin obtained in embodiment 9;

Fig. 2 is the scanning electron micrograph of water-meets-oil double-absorption resin, wherein A is the resin obtained in Example 2, and B is the resin obtained in Example 4.

Detailed ways

The present invention will be described in detail below in conjunction with specific examples.

Example 1:

Add 8g of distilled water, 1g of acrylamide, 0.1g of N,N-methylenebisacrylamide, 4.5g of methyl methacrylate, 4.5g of lauryl methacrylate, 0.05g of divinylbenzene, 1.8 1g sodium lauryl sulfate, 5.5g n-butanol, 0.3g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix at a speed of 500 rpm to form a single-phase colorless transparent double continuous The microemulsion was statically reacted in a water bath at 60°C for 3 hours, and the product was dried at 80°C for 24 hours, and then pulverized to obtain a water-meets-oil double-absorbent resin.

Example 2:

Add 7.5g distilled water, 1.5g acrylamide, 0.15g N,N-methylenebisacrylamide, 4.5g methyl methacrylate, 4.5g lauryl methacrylate, 0.05g divinylbenzene to the reaction vessel , 1.8g sodium lauryl sulphate, 5.9g n-butanol, 0.315g azobisisobutyronitrile, nitrogen discharge oxygen in the reaction vessel, stirring and mixing at a speed of 500 rpm to form a single-phase colorless and transparent Double continuous microemulsion, react statically in a water bath at 60°C for 3 hours, dry the product at 80°C for 24 hours, and pulverize to obtain a water-meets-oil double absorbent resin.

Example 3:

Add 7g of distilled water, 2g of acrylamide, 0.2g of N,N-methylenebisacrylamide, 4.5g of methyl methacrylate, 4.5g of lauryl methacrylate, 0.05g of divinylbenzene, 1.8 1g sodium lauryl sulfate, 6.2g n-butanol, 0.33g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix under the rotating speed of 500 rpm to form a single-phase colorless transparent double continuous The microemulsion was statically reacted in a water bath at 60°C for 3 hours, and the product was dried at 80°C for 24 hours, and then pulverized to obtain a water-meets-oil double-absorbent resin.

Example 4:

Add 6.5g distilled water, 2.5g acrylamide, 0.25g N,N-methylenebisacrylamide, 4.5g methyl methacrylate, 4.5g lauryl methacrylate, 0.05g divinylbenzene to the reaction vessel , 1.8g sodium lauryl sulfate, 6.4g n-butanol, 0.345g azobisisobutyronitrile, vent the oxygen in the reaction vessel with nitrogen gas, and stir and mix at a speed of 500 rpm to form a single-phase colorless and transparent Double continuous microemulsion, react statically in a water bath at 60°C for 3 hours, dry the product at 80°C for 24 hours, and pulverize to obtain a water-meets-oil double absorbent resin.

Example 5:

Add 8g of distilled water, 1g of acrylamide, 0.1g of N,N-methylenebisacrylamide, 3g of methyl methacrylate, 6g of lauryl methacrylate, 0.05g of divinylbenzene, 1.8g of Sodium dialkylsulfate, 5.5g n-butanol, 0.3g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix at a speed of 500 rpm to form a single-phase colorless transparent double continuous microemulsion , reacted statically in a water bath at 60°C for 3h, dried the product at 80°C for 24h, and pulverized to obtain a double-absorbent resin when meeting water and oil.

Embodiment 6:

Add 8g of distilled water, 1g of acrylamide, 0.1g of N,N-methylenebisacrylamide, 1.5g of methyl methacrylate, 7.5g of dodecyl methacrylate, 0.05g of divinylbenzene, 1.8 1g sodium lauryl sulfate, 5.5g n-butanol, 0.3g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix at a speed of 500 rpm to form a single-phase colorless transparent double continuous The microemulsion was statically reacted in a water bath at 60°C for 3 hours, and the product was dried at 80°C for 24 hours, and then pulverized to obtain a water-meets-oil double-absorbent resin.

Embodiment 7:

Add 8g of distilled water, 1g of acrylamide, 0.1g of N,N-methylenebisacrylamide, 6g of methyl methacrylate, 3g of lauryl methacrylate, 0.05g of divinylbenzene, 1.8g of Sodium dialkylsulfate, 5.5g n-butanol, 0.3g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix at a speed of 500 rpm to form a single-phase colorless transparent double continuous microemulsion , reacted statically in a water bath at 60°C for 3h, dried the product at 80°C for 24h, and pulverized to obtain a double-absorbent resin when meeting water and oil.

Embodiment 8:

Add 8g of distilled water, 1g of acrylamide, 0.15g of N,N-methylenebisacrylamide, 3g of methyl methacrylate, 6g of lauryl methacrylate, 0.072g of divinylbenzene, 1.8g of Sodium dialkylsulfate, 5.5g n-butanol, 0.4g azobisisobutyronitrile, the oxygen in the reaction vessel is exhausted by nitrogen gas, stirring and mixing at a speed of 500 rpm to form a single-phase colorless transparent double continuous microemulsion , reacted statically in a water bath at 60°C for 3h, dried the product at 80°C for 24h, and pulverized to obtain a double-absorbent resin when meeting water and oil.

Embodiment 9:

Add 7.5g distilled water, 1.5g acrylamide, 0.075g N,N-methylenebisacrylamide, 1.5g methyl methacrylate, 7.5g lauryl methacrylate, 0.03g divinylbenzene to the reaction vessel , 1.5g sodium lauryl sulfate, 6g n-butanol, 0.11g azobisisobutyronitrile, blow nitrogen to discharge the oxygen in the reaction vessel, stir and mix at a speed of 500 rpm to form a single-phase colorless transparent double Continuous microemulsion, static reaction in a water bath at 60°C for 3 hours, the product was dried at 80°C for 24 hours, and pulverized to obtain a double-absorbent resin when meeting water and oil.

The liquid absorption ratio and liquid absorption rate of the water-oil double-absorbent resins obtained in Examples 1 to 4 are shown in Table 1.

Table 1 embodiment 1～embodiment 4 gained resin liquid absorption rate and liquid absorption rate test result

test item Water absorption rate Oil absorption ratio Water absorption rate Oil absorption rate Example 1 5.7 5.8 98.5% 97.6% Example 2 5.9 5.3 95.9% 95.1% Example 3 6.4 5.1 95.1% 94.3% Example 4 6.6 4.5 92.7% 91.9%

It can be seen from Table 1 that in Examples 1 to 4, as the amount of acrylamide added to the water phase monomer increases, the water-absorbing component in the water-meets-oil double-absorbent resin increases, thus increasing the water-absorbing ratio of the resin and increasing the oil-absorbing ratio. The ratio is reduced. In order to achieve the water absorption ratio and oil absorption ratio of the resin at 5 to 6 times, it is preferred that the amount of acrylamide added is 12.5% to 28.6% of the quality of distilled water; This is because when the amount of acrylamide is less, a porous structure will be formed inside the resin, increasing the contact area between the liquid and the resin and the transmission rate of the liquid inside the resin, but this porous structure will increase with the acrylamide The increase of the amount of acrylamide decreases, so the increase of the amount of acrylamide will reduce the liquid absorption rate of the resin. In order to achieve the purpose of rapid liquid absorption of the resin, the liquid absorption rate of the resin should reach more than 95%. The preferred amount of acrylamide is distilled water. 12.5% to 20%. Based on the above, the preferred amount of acrylamide added is 12.5% to 20% of the mass of distilled water.

The liquid absorption ratio and liquid absorption rate of the obtained water and oil double-absorbent resins obtained in Example 7, Example 1, Example 5, and Example 6 are shown in Table 2.

Table 2 embodiment 7, embodiment 1, embodiment 5, embodiment 6 gained resin liquid absorption rate and liquid absorption rate test result

test item Water absorption rate Oil absorption ratio Water absorption rate Oil absorption rate Example 7 5.5 4.1 96.3% 95.2% Example 1 5.7 5.8 98.5% 97.6% Example 5 5.7 5.9 98.3% 97.5% Example 6 5.6 5.5 97.6% 96.5%

As can be seen from Table 2, from Example 7, Example 1, Example 5 to Example 6, the mass ratio of the oil phase monomer methyl methacrylate and lauryl methacrylate gradually decreases, and when water meets oil, the mass ratio decreases gradually. The oil absorption times of the absorbent resin first increased and then decreased. This is because lauryl methacrylate is a long-chain soft component monomer, and its addition can increase the oil absorption ratio of the resin, but when the addition is too large, the resin is soft, which is not conducive to the oil absorption of the resin. Methyl methacrylate is preferred. The mass ratio of ester to lauryl methacrylate is (20-100):100.

Table 3 shows the liquid absorption ratio and liquid absorption rate of the water and oil double-absorbent resin obtained in Example 8 and Example 9.

Table 3 embodiment 8, embodiment 9 gained resin liquid absorption rate and liquid absorption rate test result

Example 8 5.5 5.7 97.7% 96.9% Example 9 5.9 5.5 95.7% 95.1%

Fig. 1 is the photogram of embodiment 2 and embodiment 9 met water encounter oil double absorption resin, can find out from A that the water encounter oil resin obtained by embodiment 2 is a white massive solid, can see from B The water-meets-oleoresin obtained in Example 9 is a colorless transparent massive solid. The preparation processes of the two examples were stable without delamination.

Fig. 2 shows the scanning electron micrographs of the obtained water-meets-oil double-absorbent resins obtained in Example 2 and Example 4. As can be seen from the figure, microscopically, the water-meets-oil double-absorbents prepared by the double continuous microemulsion method Only less granular substances are produced in the resin, while the water-absorbing and swelling components of the water-absorbing and oil-absorbing dual-functional resin prepared in the Chinese patent CN102850483A are all granular and dispersed in the oil-absorbing and swelling components in a discontinuous form. The prepared double-absorbent resin with water and oil has a continuous structure of water-swellable components and oil-swellable components; in addition, when the amount of acrylamide is small, more micropores are formed inside the resin, while acrylamide When the amount added is large, the micropores formed inside the resin are less, so the preferred amount of acrylamide added is 12.5% to 20% of the mass of distilled water, which is beneficial to increase the number of micropores inside the resin and increase the liquid absorption rate of the resin.

Claims (6)

1. a double-absorbing resin meeting water and oil, is characterized in that, comprises distilled water, water phase monomer, water phase cross-linking agent, oil phase monomer, oil phase cross-linking agent, emulsifier, co-emulsifier, initiator, wherein The amount of water phase monomer added is 12.5%~20% of the mass of distilled water, the amount of water phase crosslinking agent added is 5%~15% of the mass of water phase monomer, the amount of oil phase monomer added is the same as the total mass of distilled water and water phase monomer The mass ratio of the oil phase crosslinking agent is 1:1, the amount of the oil phase crosslinking agent is 0.3%~1% of the mass of the oil phase monomer, and the amount of the initiator is 1%~4% of the sum of the mass of the water phase monomer and the oil phase monomer. The amount of emulsifier added is 15%~20% of the mass sum of distilled water and water phase monomers, and the amount of co-emulsifier added is 300%~400% of the mass of emulsifier; The water phase monomer is acrylamide, the water phase crosslinking agent is N, N-methylenebisacrylamide, and the oil phase monomer is a mixture of methyl methacrylate and lauryl methacrylate, The mass ratio of methyl methacrylate to lauryl methacrylate is (20~100): 100, the oil phase crosslinking agent is divinylbenzene, the emulsifier is sodium lauryl sulfate, and the Co-emulsifier is n-butanol, and the initiator is azobisisobutyronitrile; It is prepared by double continuous microemulsion polymerization, that is, adding distilled water, water phase monomer, water phase crosslinking agent, oil phase monomer, oil phase crosslinking agent, emulsifier, co-emulsifier and initiator into the reaction vessel in sequence, stirring and mixing After uniformly forming a single-phase colorless and transparent bicontinuous microemulsion, the polymerization reaction is carried out. 2. the preparation method of water encountering oil double absorption resin according to claim 1, is characterized in that, distilled water, water phase monomer, water phase cross-linking agent, oil phase monomer, oil phase cross-linking agent, emulsifier, The auxiliary emulsifier and the initiator are added into the reaction vessel in sequence, and the oxygen in the reaction vessel is discharged, stirred and mixed at a speed of 400-600 rpm to form a single-phase colorless and transparent double continuous microemulsion, and placed in a 40-80°C water bath Static reaction, the obtained product is dried and pulverized to obtain a water-meets-oil double-absorbent resin. 3. The preparation method of the water-meets-oil double-absorbent resin according to claim 2, characterized in that, the stirring speed is 500 rpm. 4 . The preparation method of water-oil double-absorbent resin according to claim 2 , characterized in that, the temperature of the water bath is 60° C., and the reaction is static for 3 hours. 5 . The preparation method of water and oil double-absorbent resin according to claim 2 , wherein the drying is at 80° C. for 24 hours. 6. The application of the water and oil double-absorbent resin according to claim 1 as an expansion component of water and oil absorption in oil well cement.