CN104926992A - Synthesis method for amphoteric ion copolymer for well drilling fluid - Google Patents
Synthesis method for amphoteric ion copolymer for well drilling fluid Download PDFInfo
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Abstract
The invention provides a synthesis method for an amphoteric ion copolymer for a well drilling fluid, wherein the synthesis method comprises the steps: respectively weighing N,N-dimethylallylamine and 1,3-propanesultone with the molar ratio of 2:1 to 8:1, adding 1,3-propanesultone to N,N-dimethylallylamine, carrying out a reaction for 0.5-4 h at the temperature of 10-60 DEG C, finally, filtering, extracting, and drying to obtain N,N-dimethylallyl propanesulfonate (DAPS); adding the obtained DAPS and AM into a solvent, dissolving, then transferring into a reactor, then introducing N2, carrying out a deoxygenation reaction, next adding an initiator, carrying out a reaction to obtain a colloidal solid, and precipitating with acetone to obtain a white precipitate; and drying the obtained precipitate, and then crushing to obtain the amphoteric ion copolymer. The copolymer obtained by the method can sustain a temperature as high as 180 DEG C, resists NaCl saturation, resists CaCl2 saturation, has the filtrate loss reduction amount of a polymer decreased along with the increase of the salt content, and besides has the advantages of excellent shale inhibition performance.
Description
Technical field
The present invention relates to for drilling fluid polymkeric substance and synthetic method thereof in Process of Oil Well Drilling, particularly relate to a kind of synthetic method of drilling fluid amphoteric ion copolymer.
Background technology
The kind complexity that polymer for drilling fluid relates to is various, Various Functions, but fluid loss agent is wherein the most important, is the maximum polymer treatment agent of consumption.Fluid loss agent ensures stabilizing mud properties, reduces harmful liquid invaded formation, and ensure the important additive for drilling fluid of hole diameter rule, stabilizing borehole.Along with drilling strata is increasingly sophisticated, and the increasing of exceptional well, ultra deep well and Holes of Complicated Wells quantity, have higher requirement to filtrate reducer for drilling fluid, to meet salt tolerance, (NaCl concentration is greater than 10%, CaCl
2concentration is greater than 5%) and the new demand of temperature tolerance (temperature is higher than 150 DEG C).Pasted starch, carboxymethyl cellulose, brown coal etc. are all the filtrate reducer for drilling fluid used the earliest.Along with deepening continuously and the increasingly sophisticated property of drilling strata of research, existing natural and natural modified fluid loss agent can not meet the needs of drilling condition, thus facilitates the research and development of artificial-synthetic copolymer's class fluid loss agent.
Due in amphoteric ion polymer both containing having absorption and the cation group of aquation dual function, again containing a large amount of aquation groups, fine and close hydration layer can be formed around clay particle, stop and delay water molecules and contact with surface of clay, playing the effect preventing clay particle hydration swelling; Cation group and anionic group ionize not by the impact of outside heating in water, and also likely stop the hydrolysis of amide group, therefore amphoteric ion polymer also has the advantage of temperature resistant antisalt, and its research and development application just progressively comes into one's own.Yang little Hua adopts MAOPS, AM and AA to synthesize amphoteric ion sulphonate polymer CPS-2000, all has stronger filtrate reducing, carries sticking and cut ability and inhibition effect, also have the stronger anti-salt of resistance to gentleness, anticalcium ability in various drilling fluid system.Yang Jinrong take redox system as initiator, adopt aqueous solution polymerization to synthesize zwitter-ion tetrapolymer: polyacrylamide-dimethyl diallyl ammonium chloride-2-acrylamide-2-methylpro panesulfonic acid sodium-methacrylic acid (PADAM), there is stronger dehydration ability of falling and inhibition, preferably salt tolerance and temperature tolerance.Zheng Haihong with acrylamide (AM), 2-acrylamide-2-methyl propane sulfonic (AMPS), dimethyl diallyl ammonium chloride (DMDAAC) and MALEIC ANHYDRIDE (MA) for monomer, adopt aqueous solution polymerization method, with ammonium persulphate/sodium bisulfite for initiator has synthesized amphoteric ion polymer fluid loss additive PA-1, Heat stability is good, filtrate reducing ability and temperature resistance ability strong.Yang Wen with dimethyl diallyl ammonium chloride (DMDAAC), 2-acrylamide-2-methylpro panesulfonic acid (AMPS), maleic anhydride (MA), acrylamide (AM) for monomer, redox system is initiator, the amphoteric ion polymer fluid loss additive PMADA that utilized water solution polymerization process to synthesize.He Aimin adopts the AEDMAC/AM/AA ampholyte copolymer fluid loss agent of aqueous solution polymerization method synthesis, and have good filtrate reducing, anti-collapse, reservoir protec-tion performance, temperature resistance, salt resistance are better.Chinese patent CN2008100472416 is with acrylamide 2-acrylamide-2-methylpro panesulfonic acid for monomer, and adopt aqueous solution polymerization to synthesize a kind of amphoteric ion polymer fluid loss additive, temperature resistance salt tolerance is stronger.
But the preparation of above-mentioned amphoteric ion polymer is all obtained by anions and canons monomer copolymerization.Due to restriction that is active by cationic monomers and reactivity ratio, in multipolymer, anion-content will much larger than cations, cause the quantity of positive and negative charge in multipolymer unequal, do not reach desirable " anti-polyelectrolyte " effect, polymkeric substance anti-calcium and anti-salt performance is limited.
Summary of the invention
For the deficiencies in the prior art, the invention provides a kind of synthetic method of drilling fluid amphoteric ion copolymer.The drilling fluid amphoteric ion copolymer that the inventive method obtains can heatproof up to 180 DEG C, saturated, the anti-CaCl of anti-NaCl
2saturated, and reduce with the filtrate reducing amount of the increase polymkeric substance of salt amount, also there is superior shale inhibition energy simultaneously.
The structure of the drilling fluid amphoteric ion copolymer of the present invention's synthesis is as follows:
The synthetic method of drilling fluid amphoteric ion copolymer of the present invention comprises the steps:
(1) N that mol ratio is 2:1 ~ 8:1 is taken first respectively, N-DMAA and 1,3-N-morpholinopropanesulfonic acid lactone, and to N, add PS in N-DMAA, then at the temperature of 10 ~ 60 DEG C, react 0.5 ~ 4h, finally by filtration, extracting, dry obtained N, N-dimethyl-allyl propanesulfonic acid salt;
(2) according to (5 ~ 2): the mol ratio of (5 ~ 8) takes the N obtained of step (1) respectively, N-dimethyl-allyl propanesulfonic acid salt and acrylamide, pass into N after adding dissolution with solvents
2deoxygenation reaction 0.5 ~ 1h, is warming up to 50 ~ 70 DEG C simultaneously, adds initiator for reaction 4 ~ 6h, obtain gelatinous solid after reaction, obtain white depositions with acetone precipitation after constant temperature 5 ~ 10min;
(3) throw out step (2) obtained is pulverized after dry 16 ~ 24h at 100 ~ 120 DEG C, final amphoteric ion copolymer.
In the inventive method, in step (1), the mol ratio of N, N-DMAA and PS is 3:1 ~ 5:1.
In the inventive method, PS is added drop-wise to N in step (1), in N-DMAA or directly disposablely join N, in N-DMAA, and preferably direct feed postition.Adopt and directly disposablely add the fashionable N taken, N-DMAA and PS mol ratio is 5:1 ~ 8:1.During employing dropping mode, N, N-DMAA and PS mol ratio are 2:1 ~ 5:1, can by PS heat fused before dropping.
In the inventive method, the reaction conditions of step (1) is react 1 ~ 3h at the temperature of 20 ~ 55 DEG C.
In the inventive method, in step (1), extraction solvent selects methyl alcohol or ethanol, preferred alcohol, and extraction times is 1 ~ 3h.Described drying is dry 10 ~ 20h under 30 ~ 50 DEG C of conditions.
In the inventive method, described in step (2), solvent is deionized water or salt solution, and after adding solvent, monomer total mass concentration is 20% ~ 40%, and the NaCl concentration added in described salt solution is 0 ~ 0.5mol/L.
In the inventive method, the initiator used in step (2) is Potassium Persulphate, in Sodium Persulfate, ammonium persulphate any one; Described initiator amount accounts for monomer total mass 0.4% ~ 0.7%.
Compared with prior art, the inventive method advantage is as follows:
(1) the inventive method is by 1,3-N-morpholinopropanesulfonic acid lactone joins excessive N, in N-DMAA, excessive N, N-DMAA not only can participate in reaction as raw material, and the effect of solvent can be played, avoiding in ordinary method and use poisonous acetone for solvent, is a kind of synthetic method of green.
(2) the inventive method is by control 1,3-N-morpholinopropanesulfonic acid lactone and N, mole when feeding mode of N-DMAA, solve 1,3-N-morpholinopropanesulfonic acid lactone and N, (be generally equimolar ratio reaction) when N-DMAA conventionally directly reacts, monomer N can not be obtained, the problem of N-dimethyl-allyl propanesulfonic acid salt.
(3) amphoteric ion copolymer prepared of the inventive method, because N, N-dimethyl-allyl propanesulfonic acid salt is macromolecular polymeric monomer, the polymkeric substance that its copolymerization obtains has long-chain branch.In aqueous due to the existence of long-chain branch, add the sterically hindered of polymkeric substance, increase the hydrodynamic volume of polymkeric substance, cause the trend of polymkeric substance temperature influence fracture hydrolysis to reduce, thus improve the performance of its heatproof, heatproof can reach 180 DEG C.
(4) amphoteric ion copolymer prepared of the inventive method belong in salt form amphoteric ion polymer, with traditional amphoteric ion polymer unlike, it due to electrostatic attraction effect, shows as molecular chain and curls between fresh water Middle molecule.And in high salt high calcium solution, due to the existence of small molecule salt, shield intermolecular association, intermolecular electrostatic attraction is changed into electrostatic repulsion forces, molecular chain is unfolded more.Obvious " anti-polyelectrolyte " effect that it shows makes the performance of polymkeric substance strengthen gradually with the increase of salt amount.Can the saturated and CaCl of anti-NaCl
2saturated, this is the anti-calcium and anti-salt performance that amphoteric ion polymer nearly all at present does not possess.Also containing a large amount of quaternary ammonium cationic groups in the amphoteric ion copolymer structure that the inventive method obtains, polymkeric substance is made to have superior shale inhibition energy.
Embodiment
Illustrate the effect of the inventive method below in conjunction with embodiment, but following examples do not form the restriction to the present invention program.
Embodiment 1
First N is prepared, N-dimethyl-allyl propanesulfonic acid salt.
Take 430g N, N-DMAA (DA) is poured in reactor, then puts into thermostat water bath, heats and starts to stir.Take 122g1 again, 3-N-morpholinopropanesulfonic acid lactone (PS), directly joins in DA, and temperature of reaction is 45 DEG C, obtains N after stirring reaction 3h, the thick product of N-dimethyl-allyl propanesulfonic acid salt (DAPS).Thick for DAPS transferred product wrapped in large stretch of filter paper, be positioned in Soxhlet extraction device, use ethanol is solvent extraction 3h, is placed in loft drier after extracting by filter paper packet, and dry at 50 DEG C, finally obtain pure DAPS monomer, productive rate is 94.3%.
Comparative example 1(direct reaction)
According to stoichiometric ratio DA:PS be 1:1 reaction.Taking 85gDA pours in reactor, then puts into thermostat water bath, heats and starts to stir.Take 122gPS again, directly join in DA, temperature of reaction is 20 DEG C, obtains mass polymerization product after stirring reaction 0.5h, and without DAPS monomer, productive rate is 0.During according to stoichiometric reaction, producing a large amount of heat in reaction cannot leave in time, and temperature moment sharply rises, and causes raw material DA and product D APS to be all polymerized.
Comparative example 2(ordinary method take acetone as solvent reaction)
Taking 90gDA pours in reactor, then puts into thermostat water bath, heats and starts to stir.Take 122gPS again and be dissolved in 650g acetone, directly joined in DA by mixing solutions, temperature of reaction is 60 DEG C, obtains the thick product of DAPS after stirring reaction 4h.Thick for DAPS transferred product wrapped in large stretch of filter paper, be positioned in Soxhlet extraction device, use ethanol is solvent extraction 2h, is placed in loft drier after extracting by filter paper packet, and dry at 35 DEG C, finally obtain pure DAPS monomer, productive rate is 81.7%.
Embodiment 2
Take 103gDAPS respectively, 35gAM, be transferred to reactor after adding a certain amount of deionized water dissolving, total monomer is 35%.Pass into N
2deoxygenation 1h, is warming up to 60 DEG C simultaneously, adds 0.7g Potassium Persulphate after keeping 30min, obtains gelatinous solid, obtain white depositions with acetone precipitation after reaction 6h.Pulverize after dry 24h at 110 DEG C, final DAPS/AM amphoteric ion copolymer.
Embodiment 3
Take 60gDAPS respectively, 50gAM, 15gNaCl, be transferred to reactor after adding a certain amount of deionized water dissolving, total monomer is 40%.Pass into N
2deoxygenation 1h, is warming up to 55 DEG C simultaneously, adds 0.75g ammonium persulphate after keeping 30min, obtains gelatinous solid, obtain white depositions with acetone precipitation after reaction 5h.Pulverize after dry 24h at 110 DEG C, final DAPS/AM amphoteric ion copolymer.
Comparative example 3
Tradition zwitterionic monomer A, AMPS/AM/DMDAAC terpolymer synthetic method presses document " AM/AMPS/DMDAAC multipolymer synthesis and filtrate loss controllability research thereof " (Wang Chunhua, 2012 " Shandong chemical industry ") report method preparation.
Comparative example 4
Tradition zwitterionic monomer B, AMPS/AM/AA/ cationic monomer tetrapolymer synthetic method presses the preparation of document " research of high temperature resistance resistant to sea water fluid loss agent and performance evaluation " (Wang Zhongguang, 2010 " Drilling and completion fluids ") report method.
Above-described embodiment and comparative example use the base slurry of saliferous calcic to evaluate filtrate loss controllability, and concrete evaluation method is as follows:
Fresh water-based slurry preparation: add 40g calcium bentonite and 5g sodium carbonate in 1000mL water, high-speed stirring 20min, ambient temperatare puts maintenance 24h, obtains fresh water-based slurry.
The water base slurry of saturated salt: add people 36%NaCl, high-speed stirring 20min, maintenance 24h under room temperature in 1000mL fresh water-based slurry, obtain the water base slurry of saturated salt.
Anti-salt property evaluation method: the fresh water-based slurry measuring 350mL, first adds a certain amount of NaCl, high-speed stirring 5min, then add the amphoteric ion copolymer of 1.5%, high-speed stirring 5min, press filtration vector in surveying after normal temperature maintenance 24h.By investigating the amount constantly increasing NaCl in fresh water-based slurry, measure the change of filtrate reducing amount.Wherein filtrate reducing amount is more low better.
Anticalcium method of evaluating performance: the water base slurry of saturated salt measuring 350mL, first adds a certain amount of CaCl
2, high-speed stirring 5min, then the amphoteric ion copolymer adding 2.0%, high-speed stirring 5min, press filtration vector in surveying after normal temperature maintenance 24h.Constantly CaCl is increased in the water base slurry of saturated salt
2amount, measure the change of filtrate reducing amount.
Table 1 different amphoteric ion polymer anti-salt property contrast table
Table 2 different amphoteric ion polymer anticalcium performance comparison table
Table 3 different amphoteric ion polymer heat-resisting property contrast table
| Aging temperature/DEG C | Embodiment 2 filter losses/mL | Embodiment 3 filter losses/mL | Comparative example 3 filter losses/mL | Comparative example 4 filter losses/mL |
| 120 | 7 | 6 | 33 | 11 |
| 150 | 13 | 10 | 57 | 19 |
| 180 | 22 | 18 | 126 | 47 |
Claims (12)
1. a synthetic method for drilling fluid amphoteric ion copolymer, is characterized in that: described synthetic method comprises the steps:
(1) N that mol ratio is 2:1 ~ 8:1 is taken first respectively, N-DMAA and 1,3-N-morpholinopropanesulfonic acid lactone, and to N, add PS in N-DMAA, then at the temperature of 10 ~ 60 DEG C, react 0.5 ~ 4h, finally by filtration, extracting, dry obtained N, N-dimethyl-allyl propanesulfonic acid salt;
(2) according to (5 ~ 2): the mol ratio of (5 ~ 8) takes the N obtained of step (1) respectively, N-dimethyl-allyl propanesulfonic acid salt and acrylamide, pass into N after adding dissolution with solvents
2deoxygenation reaction 0.5 ~ 1h, is warming up to 50 ~ 70 DEG C simultaneously, adds initiator for reaction 4 ~ 6h, obtain gelatinous solid after reaction, obtain white depositions with acetone precipitation after constant temperature 5 ~ 10min;
(3) throw out step (2) obtained is pulverized after dry 16 ~ 24h at 100 ~ 120 DEG C, final amphoteric ion copolymer.
2. in accordance with the method for claim 1, it is characterized in that: in step (1), the mol ratio of N, N-DMAA and PS is 3:1 ~ 5:1.
3. in accordance with the method for claim 1, it is characterized in that: PS is added drop-wise to N in step (1), in N-DMAA or directly disposablely join N, in N-DMAA.
4. according to the method described in claim 1 or 3, it is characterized in that: in step (1), PS is directly disposable joins N, in N-DMAA.
5. in accordance with the method for claim 3, it is characterized in that: adopt and directly disposablely add the fashionable N taken, N-DMAA and PS mol ratio is 5:1 ~ 8:1.
6. in accordance with the method for claim 3, it is characterized in that: during employing dropping mode, N, N-DMAA and PS mol ratio are 2:1 ~ 5:1.
7. in accordance with the method for claim 1, it is characterized in that: the reaction conditions of step (1) is react 1 ~ 3h at the temperature of 20 ~ 55 DEG C.
8. in accordance with the method for claim 1, it is characterized in that: described in step (1), extraction solvent selects methyl alcohol or ethanol, described extraction times is 1 ~ 3h.
9. in accordance with the method for claim 1, it is characterized in that: dry described in step (1) is 10 ~ 20h dry at 30 ~ 50 DEG C.
10. in accordance with the method for claim 1, it is characterized in that: described in step (2), solvent is deionized water or salt solution, the NaCl concentration added in described salt solution is 0 ~ 0.5mol/L.
11. in accordance with the method for claim 1, it is characterized in that: after adding solvent, monomer total mass concentration is 20% ~ 40%.
12. in accordance with the method for claim 1, it is characterized in that: the initiator used in step (2) is Potassium Persulphate, in Sodium Persulfate, ammonium persulphate any one, described initiator amount accounts for monomer total mass 0.4% ~ 0.7%.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002046253A2 (en) * | 2000-12-08 | 2002-06-13 | Hercules Incorporated | Polymeric fluid loss additives and method of use thereof |
| CN102875728A (en) * | 2012-10-30 | 2013-01-16 | 中国石油化工股份有限公司 | Zwitterionic polymer anti-collapse agent for foam drilling |
| CN103509535A (en) * | 2012-06-29 | 2014-01-15 | 中国石油化工股份有限公司 | Filtrate loss reduction method for water-based drilling fluid, and preparation method for filtrate loss reducer |
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2014
- 2014-03-19 CN CN201410100623.6A patent/CN104926992B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002046253A2 (en) * | 2000-12-08 | 2002-06-13 | Hercules Incorporated | Polymeric fluid loss additives and method of use thereof |
| CN103509535A (en) * | 2012-06-29 | 2014-01-15 | 中国石油化工股份有限公司 | Filtrate loss reduction method for water-based drilling fluid, and preparation method for filtrate loss reducer |
| CN102875728A (en) * | 2012-10-30 | 2013-01-16 | 中国石油化工股份有限公司 | Zwitterionic polymer anti-collapse agent for foam drilling |
Non-Patent Citations (1)
| Title |
|---|
| 丁伟 等: ""磺基甜菜碱型两性离子聚合物的合成"", 《化工科技》 * |
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