CN1425738A - Cation polymer oil-displacing agent and its preparing method - Google Patents
Cation polymer oil-displacing agent and its preparing method Download PDFInfo
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- CN1425738A CN1425738A CN 02151528 CN02151528A CN1425738A CN 1425738 A CN1425738 A CN 1425738A CN 02151528 CN02151528 CN 02151528 CN 02151528 A CN02151528 A CN 02151528A CN 1425738 A CN1425738 A CN 1425738A
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Abstract
The present invention relates to the preparation of water soluble cation polymer and its application in oil displacement in oil field. The compound is obtained through grafting quaternary ammonium salt type cation to active hydrogen-containing group in natural high molecular guar gum, cellulose, xanthan gum, starch or polymer or is water soluble cationic polymer obtained through homopolymerization or copolymerization. The compound can increase the viscosity of water drive, weaken the adsorption of crude oil to stratum and reach high oil displacing effect. It may be used alone as oil displacing agent or matched with polymer oil displacing agent or surfactant. The cationic polymer has high temperature resistance and excellent salt tolerance and may be used also in petroleum deposit not suitable for available polymer drive.
Description
(1) technical field
The present invention relates to the oil-displacing agent in petroleum industry field, be specifically related to cation high molecular oil-displacing agent NCP (newcationic polymer) and preparation method thereof.
(2) technical background
The water-soluble cationic polymer has purposes widely in fields such as papermaking, oil, water treatment and daily-use chemical industries.Particularly in petroleum industry, from drilling mud, chemical agent for oil recovery the important application of cation high molecular is arranged all to aspects such as disposing polluted water in oil, but, limited being extensive use of of it because the price of domestic this series products is higher at present.The present invention. middle NCP is a kind of New Cationic Polymer that widespread use is worth that has.
The method for preparing cation high molecular mainly contains two kinds: a kind of is to be that raw material makes by homopolymerization or copolyreaction with the cationic polymerization monomer; Another kind is to carry out chemical reaction and get with the reactive group on cationic reagent and the macromolecular chain such as hydroxyl, amino etc., and the latter abbreviates the high molecular weight reactive method as.
In the oilfield chemistry field, present all research signs and domestic and international pertinent data show, the research of oil field chemical has non-ionic type from the past, anionic to having the trend that cationic compound ion type transforms transition, the oil field chemical that contains positively charged ion or compound ion group is one of important directions of research at present, and cation high molecular and Amphiphatic high polymer have in oil-field development widely to be used.As chemical displacement of reservoir oil method, polymer flooding and surfactant flooding and binary, ternary composite driving have all carried out long-term both at home and abroad and extensive studies is not seen new breakthrough at present.
(3) summary of the invention
At the deficiencies in the prior art, the invention provides a kind of water-soluble cationic macromolecule oil-displacing agent and preparation method thereof, be applied in and improve oil recovery factor in the oil field.
Water-soluble cationic macromolecule oil-displacing agent of the present invention, can be in natural polymer such as guar gum, Mierocrystalline cellulose, xanthan gum, perhaps synthetic polymer such as polyacrylamide or polyvinyl alcohol contains the compound that inserts the positively charged ion of quaternary on the active hydrogen group and obtain; Or be the water-soluble cationic polymer that raw material makes by homopolymerization or copolyreaction with the cationic polymerization monomer.The cationic quaternary ammonium unit structure that inserts is as follows:
Water-soluble cationic polymer of the present invention can increase the viscosity of water, with stratum and crude oil stronger interaction is arranged, and weakens the absorption of crude oil to the stratum, improves the displacement effect.
Be the preparating mechanism of example explanation cation high molecular below with the Mierocrystalline cellulose.
Cellulosic general molecular formula is [C
6H
7O
3(OH)
2]
n, molecular weight is at 108-109, and introducing quaternary ammonium cation group (is example with the epoxypropyl trimethylammonium chloride ammonium) can make Mierocrystalline cellulose react and obtain the water-soluble cationic Mierocrystalline cellulose on hydroxyl, and the high molecular preparating mechanism of water-soluble cationic of the present invention is as follows:
Epoxypropyl trimethylammonium chloride ammonium Mierocrystalline cellulose cationic polymers NCP
Mierocrystalline cellulose can use guar gum, xanthan gum, starch, xylogen, chitin to substitute in the above-mentioned reaction mechanism formula, and the epoxypropyl trimethylammonium chloride ammonium can substitute with following positively charged ion:
Above-mentioned synthetic method is the high molecular weight reactive method, and this method has two kinds of reaction paths usually: solid phase method and liquid phase method.Can adopt solid phase method also can adopt liquid phase method, and all can obtain the cationic polymers of high-cation degree by these two kinds of methods.Concrete synthetic method is as follows:
In reactor, add the Mierocrystalline cellulose of 100 weight parts, add 3～7% activator Na that are equivalent to natural polymer or polymer weight
2CO
3With 5 ‰-11 ‰ catalyzer perchloric acid, at room temperature stirred 20～40 minutes, add cationic reagents such as equivalent (3-chloro-2-hydroxyl) oxypropyl trimethyl ammonium chloride again, at room temperature continue to stir 3～4 hours, reacted 2～4 hours down at 70 ℃～90 ℃, can obtain the cation high molecular polymer oil-displacing agent.Reaction process as shown in Figure 1.
The factor that influences the cationic polymers quality product respond medium, temperature of reaction, reaction times, feed ratio and pH value etc., owing to can determine reaction medium and material ratio according to reaction mechanism before the experiment, so main influence of considering temperature of reaction, catalyzer add-on and reaction times to the reaction efficiency (RE) and the substitution value (DS) of cationic polymers in desk research, we adopt orthogonal experiment method, and experimental result is as shown in table 1:
Table 1 orthogonal experiment is measured top condition
| Sequence number | Catalyzer/g | Time/h | Temperature/℃ | ?DS | ?RE/％ |
| ?1 | ??0.05 | ??1.5 | ?80 | ?0.425 | ?63.6 |
| ?2 | ??0.05 | ??2.5 | ?95 | ?0.470 | ?70.0 |
| ?3 | ??0.05 | ??3.5 | ?110 | ?0.446 | ?68.8 |
| ?4 | ??0.08 | ??1.5 | ?95 | ?0.486 | ?72.8 |
| ?5 | ??0.08 | ??2.5 | ?110 | ?0.508 | ?70.0 |
| ?6 | ??0.08 | ??3.5 | ?80 | ?0.554 | ?82.9 |
| ?7 | ??0.11 | ??1.5 | ?110 | ?0.489 | ?73.2 |
| ?8 | ??0.11 | ??2.5 | ?80 | ?0.543 | ?81.3 |
| ?9 | ??0.11 | ??3.5 | ?95 | ?0.489 | ?73.2 |
By our best as can be seen catalyst levels (about 0.08), optimum reacting time (3h) and optimal reaction temperature (70 ℃-90 ℃) of table 1 data.
Cationic polymers NCP is used as the indoor natural core oil displacement experiment of oil-displacing agent.Method one: the oil displacement experiment that on the oil field output sand of granularity, carries out the NCP of different concns (1%, 0.5%) less than 0.5mm; Method two: after polymer anion (1500ppm) displacement of reservoir oil, use the experiment of positively charged ion displacement again.Experimental temperature is 80 ℃, and experimental water is a laboratory simulation oil field stratum water, and 80 ℃ viscosity is 0.47mPaS.
Different recovery ratio (the long-pending 65cm that are of the original eleoplast of rock core that inject under the pv number of table 2
3)
| The experiment sequence number | Rate of permeation um 2 | Cation concn | Anion concentration ppm | Water drive | Negatively charged ion drives end | Positively charged ion drives end | Water drive 2To moisture=98% | ||||
| Cumulative injection pv | Recovery ratio η 1％ | Cumulative injection pv | Recovery ratio η 2％ | Cumulative injection pv | Recovery ratio η 3％ | Cumulative injection pv | Recovery ratio η 4％ | ||||
| 1 | 0.458 | 1％ | / | 0.47 | 30.25 | / | / | 1.213 | 56 | 2.5 | 64.15 |
| 2 | 1.46 | 1％ | / | 1.75 | 50.6 | / | / | 2.1 | 53.7 | 4.6 | 68.6 |
| 3 | 1.44 | 0.5％ | / | 2.6 | 46.3 | / | / | 3.5 | 49.5 | 5.1 | 64 |
| 4 | 1.24 | 0.5％ | 1500 | 1.84 | 52.2 | 2.34 | 53.6 | 3.27 | 71.1 | 4.8 | 80.2 |
The raising of recovery ratio after the positively charged ion displacement of table 3 polymkeric substance and different concns
| The experiment sequence number | Cation concn | Anion concentration ppm | Water drive 1 | Negatively charged ion drives | Positively charged ion injects the pv number | Recovery ratio improves (η after annotating the positively charged ion slug 4-η 1)％ | ||
| Cumulative injection pv | Water ratio % | Inject the pv number | Recovery ratio improves η 2-η 1 | |||||
| 1 | 1％ | / | 0.47 | 76.6 | / | / | 0.47 | 33.9 |
| 2 | 1％ | / | 1.75 | 98 | / | / | 0.47 | 18 |
| 3 | 0.5％ | / | 2.6 | 98 | / | / | 0.94 | 17.7 |
| 4 | 0.5％ | 1500 | 1.84 | 98 | 0.47 | 1.4％ | 0.94 | 28 η 4-η 2＝26.6 |
Can obtain to draw a conclusion from indoor oil displacement experiment result:
Under experiment condition, 1% the positively charged ion slug 0.47pv of reinjecting behind the water drive 0.47pv, recovery ratio can improve 33.9%;
After water drive arrives moisture 98%, the cationic polymers that reinjects, recovery ratio still has by a relatively large margin and improves.After positively charged ion displacement for some time, recovery ratio obviously raises;
After the negatively charged ion displacement, use the displacement of positively charged ion slug again, the recovery ratio of raising crude oil that also can be by a relatively large margin.
The cation high molecular oil-displacing agent both can use as oil-displacing agent separately, also can cooperate polymer oil-displacing agent or tensio-active agent to use.And this cation high molecular has higher temperature tolerance, good salt resistance, and the oil reservoir that is not suitable for present polymer flooding also had important meaning
(4) description of drawings
Fig. 1 is the reacting flow chart of the inventive method.
(5) embodiment embodiment 1. cationic polymers NCP
In reactor, add the Mierocrystalline cellulose of 100 grams, add the 5% wetting agent Na that is equivalent to cellulose
2CO
3With 8 ‰ catalyzer perchloric acid, at room temperature stirred 25 minutes, and added equivalent cationic reagent epoxypropyl trimethylammonium chloride ammonium again, at room temperature continue to stir 3 hours, reacted 3 hours down at 80 ℃, can obtain cation high molecular Polymer NCP oil-displacing agent.Embodiment 2. cationic polymers NCP
In reactor, add the guar gum of 100 grams, add the 6% wetting agent Na that is equivalent to guar gum weight
2CO
3With 9 ‰ catalyzer perchloric acid, at room temperature stirred 30 minutes, and added equivalent cationic reagent (3-chloro-2-hydroxyl) oxypropyl trimethyl ammonium chloride again, at room temperature continue to stir 3 hours, reacted 3 hours down at 80 ℃, can obtain cation high molecular Polymer NCP oil-displacing agent.Embodiment 3. cationic polymers NCP
In reactor, add the xanthan gum of 100 grams, add the 3% wetting agent Na that is equivalent to xanthan gum weight
2CO
3Catalyzer perchloric acid with 7 ‰ at room temperature stirred 30 minutes, added equivalent cationic reagent chloroethyl trimethyl ammonium chloride again, at room temperature continued to stir 4 hours, reacted 3 hours down at 80 ℃, can obtain cation high molecular Polymer NCP oil-displacing agent.Embodiment 4. cationic polymers NCP
In reactor, add the xylogen of 100 grams, add the 5% wetting agent Na that is equivalent to xylogen weight
2CO
3With 8 ‰ catalyzer perchloric acid, at room temperature stirred 30 minutes, and added equivalent cationic reagent (3-chloro-2-hydroxyl) oxypropyl trimethyl ammonium chloride again, at room temperature continue to stir 4 hours, reacted 4 hours down at 85 ℃, can obtain cation high molecular Polymer NCP oil-displacing agent.Embodiment 5. cationic polymers NCP
In reactor, add the W-Gum of 100 grams, add the 7% wetting agent Na that is equivalent to its weight
2CO
3With 5 ‰ catalyzer perchloric acid, at room temperature stirred 40 minutes, and added equivalent cationic reagent diallyldimethylammonium chloride again, at room temperature continue to stir 3 hours, reacted 4 hours down at 85 ℃, can obtain cation high molecular Polymer NCP oil-displacing agent.Embodiment 6. usefulness cation high molecular NCP do indoor oil displacement experiment:
(1) with well head output sandfilling basket;
(2) rock core saturation water, water is surveyed rate of permeation, calculates volume of voids and porosity;
(3) rock core saturated oil;
(4) each experiment of following steps is all different:
Experiment 1: carry out water drive (volume of water input 37.5ml) with the speed of 1ml/min; With same speed, inject 1% cation high molecular 37.5ml; Water drive is to moisture 98%.
Experiment 2: carry out water drive to moisture 98% with the speed of 1ml/min; With same speed, inject 1% cation high molecular 37.5ml; Water drive is to moisture 98%.
Experiment 3: carry out water drive to moisture 98% with the speed of 1ml/min; With same speed, inject 0.5% cation high molecular 75ml; Water drive is to moisture 98%.
Experiment 4: carry out water drive to moisture 98% with the speed of 1ml/min; With same speed, inject the anionic polymer 37.5ml of 1500ppm; Then inject 0.5% cation high molecular 75ml; Water drive is to moisture 98%.Water drive writes down accumulation produce oil, water production rate and the pressure of different time to a certain water ratio;
Above result of experiment has provided shown in top table 2 table 3.
Claims (3)
1. the cation high molecular oil-displacing agent is characterized in that, at natural polymer guar gum, Mierocrystalline cellulose, xanthan gum or starch, perhaps inserts the positively charged ion of quaternary on the group that contains reactive hydrogen of polymkeric substance such as polyacrylamide or polyvinyl alcohol and the compound that obtains; Or be the water-soluble cationic polymer that raw material makes by homopolymerization or copolyreaction with the cationic polymerization monomer.
2. cation high molecular oil-displacing agent as claimed in claim 1 is characterized in that, the cationic quaternary ammonium unit structure that is inserted is as follows:
3. the preparation method of the described cation high molecular oil-displacing agent of claim 1 comprises the steps:
In reactor, add natural polymer such as guar gum, Mierocrystalline cellulose, xanthan gum, starch or the xylogen of 100 weight parts, add 3～7% wetting agent Na that are equivalent to natural polymer or polymer weight
2CO
3With 5 ‰-11 ‰ catalyzer perchloric acid, at room temperature stirred 20～40 minutes, add cationic reagents such as equivalent epoxypropyl trimethylammonium chloride ammonium, chloroethyl trimethyl ammonium chloride, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride, diallyldimethylammonium chloride again, at room temperature continue to stir 3～4 hours, reacted 2～4 hours down at 70 ℃～90 ℃, obtain the cation high molecular polymer oil-displacing agent.
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| CN102051165A (en) * | 2009-10-27 | 2011-05-11 | 中国石油化工股份有限公司 | Xanthan gum graft copolymer oil displacement agent as well as preparation method and application thereof |
| CN102453167A (en) * | 2010-10-25 | 2012-05-16 | 中国石油化工股份有限公司 | Polymer displacement agent, preparation method thereof, and oil displacement method for oil reservoirs |
| CN102794133A (en) * | 2012-05-08 | 2012-11-28 | 内蒙古大学 | Cationic surfactant and preparation method thereof |
| CN104327821A (en) * | 2014-09-15 | 2015-02-04 | 西南石油大学 | Amphiphilic modified chitosan degradable oil displacement agent and preparation method thereof |
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- 2002-12-31 CN CNB02151528XA patent/CN1189533C/en not_active Expired - Fee Related
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| CN102453167B (en) * | 2010-10-25 | 2013-09-04 | 中国石油化工股份有限公司 | Polymer oil displacement agent, preparation method thereof, and oil displacement method for oil reservoirs |
| CN102794133A (en) * | 2012-05-08 | 2012-11-28 | 内蒙古大学 | Cationic surfactant and preparation method thereof |
| CN105980656A (en) * | 2013-10-23 | 2016-09-28 | 国际壳牌研究有限公司 | Process for recovery of oil from an oil-bearing formation |
| CN104632151A (en) * | 2013-11-12 | 2015-05-20 | 中国石油天然气股份有限公司 | Method for improving recovery efficiency by ion matching water drive |
| CN104327821A (en) * | 2014-09-15 | 2015-02-04 | 西南石油大学 | Amphiphilic modified chitosan degradable oil displacement agent and preparation method thereof |
| CN104327821B (en) * | 2014-09-15 | 2015-08-19 | 西南石油大学 | Amphiphilic modified chitosan degradable oil-displacing agent and preparation method thereof |
| CN105622451B (en) * | 2015-12-29 | 2017-09-29 | 四川光亚聚合物化工有限公司 | A kind of long chain alkyl ammonium salt monomer, its preparation method and association polymer |
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| CN114133922A (en) * | 2020-09-04 | 2022-03-04 | 中国石油化工股份有限公司 | Water-soluble oil washing agent and preparation method and application thereof |
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