A dispersant, a suspension containing the same, a water-based drilling fluid, and a water-based fracturing fluid

Abstract

The present invention provides a dispersant, a suspension containing the same, a water-based drilling fluid and a water-based fracturing fluid. The dispersant comprises diethanolamide of linoleic acid, sodium dodecyl sulfate, isomeric tridecanol polyoxyethylene ether, triethylene glycol butyl ether, a tackifier and a solvent.

Description

Technical Field

[0001] This invention relates to the field of oil and gas extraction, and particularly to a dispersant for suspended water-soluble polymers. Background Technology

[0002] Water-soluble polymers have become indispensable processing agents in oil and gas extraction technology. They are usually in powder form and are widely used in working fluids such as drilling fluids, fracturing fluids, and well-killing fluids. Under normal circumstances, water-soluble polymers have a high molecular weight. In order to fully exert their performance, they need to be dissolved in water in advance. Only after they are fully dissolved can they be mixed with other processing agents to form a working fluid. However, in field applications, there are problems such as easy formation of "fish eyes", long dissolution time, and incomplete dissolution. They cannot be prepared and used immediately, and the polymer dosage cannot be adjusted in real time according to the needs of the site to change the performance of the working fluid. Their application has great limitations.

[0003] Currently, there is no method to overcome the shortcomings of existing mature polymer products in field applications and improve the efficiency of polymer product use. Summary of the Invention

[0004] One aspect of the present invention provides a dispersant for suspensions comprising linoleic acid diethanolamide, sodium dodecyl sulfate, isotridecyl alcohol polyoxyethylene ether, triethylene glycol butyl ether, a thickener, and a solvent.

[0005] In one specific embodiment, the thickening agent is organic bentonite.

[0006] In one specific embodiment, the solvent is white oil.

[0007] In one specific embodiment, the solvent is at least one of No. 3 white oil, No. 5 white oil, and No. 15 white oil.

[0008] In one specific embodiment, based on 100 parts by mass of the dispersant, the following components are present: 1 to 2 parts of linoleic acid diethanolamide, 1 to 3 parts of sodium dodecyl sulfate, 2 to 3 parts of isomeric tridecyl alcohol polyoxyethylene ether, 0.4 to 0.6 parts of triethylene glycol butyl ether, 1 to 3 parts of the thickening agent, and the remainder being solvent.

[0009] The second invention provides a suspension comprising a water-soluble polymer and a dispersant as described in any one of the inventions.

[0010] In one specific embodiment, the water-soluble polymer is at least one of xanthan gum, sodium carboxymethyl cellulose, polyanionic cellulose, hydrolyzed polyacrylamide, hydrolyzed potassium polyacrylamide, hydrolyzed polyacrylonitrile, zwitterionic polymer FA367, potassium polyacrylamide, and guar gum.

[0011] In one specific embodiment, the degree of hydrolysis of the hydrolyzed polyacrylamide and the hydrolyzed polyacrylamide potassium salt is independently between 20% and 40%, and the relative molecular weights of the hydrolyzed polyacrylamide and the hydrolyzed polyacrylamide potassium salt are independently between 100,000 and 5,000,000.

[0012] In one specific embodiment, the degree of hydrolysis of the hydrolyzed polyacrylamide or the hydrolyzed polyacrylamide potassium salt is 30%, the relative molecular weight of the hydrolyzed polyacrylamide is 3 million, and the relative molecular weight of the hydrolyzed polyacrylamide potassium salt is 5 million.

[0013] In one specific embodiment, the hydrolyzed polyacrylonitrile salt is a hydrolyzed polyacrylonitrile ammonium salt and / or a hydrolyzed polyacrylonitrile potassium salt.

[0014] In one specific embodiment, the degree of hydrolysis of the hydrolyzed polyacrylonitrile salt is 50% to 60%, and the relative molecular weight of the hydrolyzed polyacrylonitrile salt is 10,000 to 100,000.

[0015] In one specific embodiment, the degree of hydrolysis of the hydrolyzed polyacrylonitrile salt is 50%, and the relative molecular weight of the hydrolyzed polyacrylonitrile salt is 10,000.

[0016] In one specific embodiment, the guar gum is at least one of natural guar gum, hydroxypropyl guar gum, carboxymethyl guar gum, and hydroxypropyl carboxymethyl guar gum.

[0017] In one specific embodiment, the ratio of the water-soluble polymer to the dispersant is (30 to 55): 50.

[0018] The third invention provides a drilling fluid comprising a suspension as described in any one of the second inventions.

[0019] In one specific embodiment, the drilling fluid is a water-based drilling fluid.

[0020] The fourth invention provides a fracturing fluid comprising a suspension as described in any one of the second inventions.

[0021] In one specific embodiment, the fracturing fluid is a water-based fracturing fluid.

[0022] The beneficial effects of this invention are:

[0023] The suspension dispersant of this invention utilizes the synergistic effect of linoleic acid diethanolamide, sodium dodecyl sulfate, isomeric tridecyl alcohol polyoxyethylene ether, and triethylene glycol butyl ether to transform powdered water-soluble polymer products into a suspension with high dispersibility, high stability, high solid content, and good fluidity without altering the properties of the water-soluble polymer. This improves the dissolution rate of the water-soluble polymer in water, overcomes the shortcomings of water-soluble polymer products during use, and enhances the efficiency of their use. After the water-soluble polymer is suspended in the dispersant to form a suspension, when the suspension is then dissolved in water, the complete dissolution time of the water-soluble polymer can reach less than 60 seconds, significantly improving the dissolution rate. Furthermore, the transformed water-soluble polymer suspension does not affect the performance of drilling fluids or fracturing fluids during use, and can be prepared and used immediately as needed, meeting the requirement of adjusting the performance of drilling fluids or fracturing fluids at any time. Detailed Implementation

[0024] The present invention will be further described below with reference to the embodiments. However, the embodiments of the present invention are merely illustrative examples and should not be construed as limiting the present invention under any circumstances.

[0025] Anhydrous sodium carbonate, potassium chloride, ferric chloride, calcium chloride, magnesium chloride, and sodium chloride are all chemically pure.

[0026] The bentonite used for drilling fluid test slurry preparation was purchased from Bohai Drilling Engineering Company.

[0027] The zwitterionic polymer FA367, sulfomethylphenol resin SMP-2, and lignite resin SPNH were all purchased from Chengdu Chuanfeng Chemical Co., Ltd.

[0028] The sulfonated asphalt FT-3 was purchased from Xinxiang No. 7 Chemical Co., Ltd., Henan Province.

[0029] Organic bentonite, polyanionic cellulose, drilling fluid lubricant RH220, ultrafine calcium carbonate, plugging agent FDM, plugging agent FDFT-1, and barite were all purchased from Chengdu Xiyou Huawai Technology Co., Ltd.

[0030] Hydrolyzed polyacrylonitrile ammonium salt with a degree of hydrolysis of 50% and a relative molecular mass of 10,000 was purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd.

[0031] Hydrolyzed polyacrylonitrile potassium salt with a degree of hydrolysis of 50% and a relative molecular mass of 10,000 was purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd.

[0032] Hydrolyzed polyacrylamide potassium salt with a degree of hydrolysis of 30% and a relative molecular mass of 5 million was purchased from Sichuan Xinchuangneng Petroleum Engineering Technology Co., Ltd.

[0033] Hydrolyzed polyacrylamide with a degree of hydrolysis of 30% and a relative molecular mass of 3 million was purchased from Sichuan Guangya Polymer Chemical Co., Ltd.

[0034] Hydroxypropyl guanidine gum was purchased from Dongying Shipuri Petroleum Engineering Technology Co., Ltd.

[0035] Preparation of dispersants

[0036] Example 1

[0037] 1): Add 1g of linoleic acid diethanolamide, 1g of sodium dodecyl sulfate, 2g of isotridecyl alcohol polyoxyethylene ether and 0.4g of triethylene glycol butyl ether to 94.6g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0038] 2): Add 1g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 1# for suspension.

[0039] Example 2

[0040] 1): Add 2g of linoleic acid diethanolamide, 3g of sodium dodecyl sulfate, 3g of isotridecyl alcohol polyoxyethylene ether and 0.6g of triethylene glycol butyl ether to 88.4g of No. 3 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0041] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 2# for suspension.

[0042] Example 3

[0043] 1): Add 1.5g of linoleic acid diethanolamide, 2g of sodium dodecyl sulfate, 2.5g of isotridecyl alcohol polyoxyethylene ether and 0.5g of triethylene glycol butyl ether to 91.5g of No. 5 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0044] 2): Add 2g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 3# for suspension.

[0045] Example 4

[0046] 1): Add 2g of linoleic acid diethanolamide, 3g of sodium dodecyl sulfate, 3g of isotridecyl alcohol polyoxyethylene ether and 0.6g of triethylene glycol butyl ether to 88.4g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0047] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 4# for suspension.

[0048] Example 5

[0049] 1): Add 1g of linoleic acid diethanolamide, 1g of sodium dodecyl sulfate, 2g of isotridecyl alcohol polyoxyethylene ether and 0.4g of triethylene glycol butyl ether to 94.6g of No. 3 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0050] 2): Add 1g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 5# for suspension.

[0051] Example 6

[0052] 1): Add 2g of linoleic acid diethanolamide, 2g of sodium dodecyl sulfate, 3g of isotridecyl alcohol polyoxyethylene ether and 0.4g of triethylene glycol butyl ether to 91.6g of No. 5 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0053] 2): Add 1g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant 6# for suspension;

[0054] Example 7

[0055] 1): Add 1g of linoleic acid diethanolamide, 2g of sodium dodecyl sulfate, 2g of isotridecyl alcohol polyoxyethylene ether and 0.6g of triethylene glycol butyl ether to 91.4g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0056] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant #7 for suspension.

[0057] Example 8

[0058] 1): Add 2g of linoleic acid diethanolamide, 1g of sodium dodecyl sulfate, 2g of isotridecyl alcohol polyoxyethylene ether and 0.6g of triethylene glycol butyl ether to 92.4g of No. 3 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0059] 2): Add 2g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant #8 for suspension.

[0060] Example 9

[0061] 1): Add 1g of linoleic acid diethanolamide, 1g of sodium dodecyl sulfate, 2g of isotridecyl alcohol polyoxyethylene ether and 0.4g of triethylene glycol butyl ether to 94.6g of No. 5 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0062] 2): Add 1g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain suspension dispersant 9#;

[0063] Comparative Example 1

[0064] 1): Add 2g of linoleic acid diethanolamide, 3g of sodium dodecyl sulfate, 3g of isotridecyl alcohol polyoxyethylene ether, and 0.6g of triethylene glycol butyl ether to 91.4g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain dispersant D1# for suspension.

[0065] Comparative Example 2

[0066] 1): Add 3g of sodium dodecyl sulfate, 3g of isotridecyl alcohol polyoxyethylene ether, and 0.6g of triethylene glycol butyl ether to 90.4g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture.

[0067] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant D2# for suspension.

[0068] Comparative Example 3

[0069] 1): Add 2g of linoleic acid diethanolamide, 2g of isotridecyl alcohol polyoxyethylene ether, and 0.6g of triethylene glycol butyl ether to 92.4g of No. 3 white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture;

[0070] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant D3# for suspension.

[0071] Comparative Example 4

[0072] 1): Add 2g of linoleic acid diethanolamide, 3g of sodium dodecyl sulfate and 0.6g of triethylene glycol butyl ether to 91.4g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture;

[0073] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant D4# for suspension.

[0074] Comparative Example 5

[0075] 1): Add 2g of linoleic acid diethanolamide, 3g of sodium dodecyl sulfate and 3g of isotridecyl alcohol polyoxyethylene ether to 89g of 15# white oil, and stir for 30 minutes at 400-1000r / min to obtain a mixture;

[0076] 2): Add 3g of organic bentonite to the mixture and stir for 60 minutes at 400-1000r / min to obtain dispersant D5# for suspension.

[0077] Preparation of suspension

[0078] Example 10

[0079] Add 110g of polyanionic cellulose to 100g of dispersant 1# and stir for 60 minutes at 400-1000r / min to obtain suspension 1#.

[0080] Example 11

[0081] Add 80g of zwitterionic polymer FA367 to 100g of dispersant 2#, and stir for 60 minutes at 400-1000r / min to obtain suspension 2#.

[0082] Example 12

[0083] Add 100g xanthan gum to 100g dispersant 3# and stir for 60 minutes at 400-1000r / min to obtain suspension 3#.

[0084] Example 13

[0085] Add 90g of hydrolyzed polyacrylamide with a degree of hydrolysis of 30% and a relative molecular mass of 3 million to 100g of dispersant 4#, and stir for 60 minutes at 400-1000r / min to obtain suspension 4#.

[0086] Example 14

[0087] Add 60g of hydroxypropyl guanidine gum to 100g of dispersant 5#, and stir for 60 minutes at 400-1000r / min to obtain suspension 5#.

[0088] Example 15

[0089] Add 70g of sodium carboxymethyl cellulose to 100g of dispersant 6# and stir for 60 minutes at 400-1000r / min to obtain suspension 6#.

[0090] Example 16

[0091] Add 110g of hydrolyzed polyacrylonitrile ammonium salt with a degree of hydrolysis of 50% and a relative molecular mass of 10,000 to 100g of dispersant 7#, and stir for 60 minutes at 400-1000r / min to obtain suspension 7#.

[0092] Example 17

[0093] Add 80g of hydrolyzed polyacrylonitrile potassium salt with a degree of hydrolysis of 50% and a relative molecular mass of 10,000 to 100g of dispersant 8#, and stir for 60 minutes at 400-1000r / min to obtain suspension 8#.

[0094] Example 18

[0095] Add 60g of potassium polyacrylamide with a degree of hydrolysis of 30% and a relative molecular mass of 5 million to 100g of dispersant 9#, and stir for 60 minutes at 400-1000r / min to obtain a suspension.

[0096] Comparative Example 6

[0097] Add 110g of polyanionic cellulose to 100g of dispersant D1# and stir for 60 minutes at 400-1000r / min to obtain a suspension.

[0098] Comparative Example 7

[0099] Add 80g of zwitterionic polymer FA367 to 100g of dispersant D2# and stir for 60 minutes at 400-1000r / min to obtain a suspension.

[0100] Comparative Example 8

[0101] Add 100g xanthan gum to 100g dispersant D3# and stir for 60 minutes at 400-1000r / min to obtain a suspension.

[0102] Comparative Example 9

[0103] Add 90g of hydrolyzed polyacrylamide with a degree of hydrolysis of 30% and a relative molecular mass of 3 million to 100g of dispersant D4#, and stir for 60 minutes at 400-1000 r / min to obtain a suspension.

[0104] Comparative Example 10

[0105] Add 60g of hydroxypropyl guanidine gum to 100g of dispersant D5# and stir for 60 minutes at 400-1000r / min to obtain a suspension.

[0106] Preparation of water-based drilling fluid:

[0107] Example 19

[0108] The weighting material used in this embodiment is barite, with a density of 4.3 g / cm³. 3 .

[0109] Step 1: Measure 400 mL of water, add 0.64 g of anhydrous sodium carbonate and 16 g of bentonite for drilling fluid preparation under high-speed stirring at (11000±300) r / min, stir at high speed for 20 min, stop the stirrer halfway, scrape off the bentonite adhering to the container wall and stirring rod with a glass rod, seal and cure at 25℃±3℃ for 24 h to obtain bentonite-based slurry;

[0110] Step 2: Under high-speed stirring conditions of (11000±300) r / min, 1.8g of Suspension 2# of Example 11 was added to the bentonite-based slurry in sequence. After complete dissolution, 5.4g of Suspension 1# of Example 10 was added. After complete dissolution, 4.6g of Suspension 7# of Example 16 was added. After complete dissolution, the first mixture was obtained. The complete dissolution time was measured when each suspension was added.

[0111] Step 3: Under high-speed stirring conditions of (11000±300)r / min, add 6g of drilling fluid lubricant RH220 to the first mixture, and stir at high speed for 10min to obtain the second mixture;

[0112] Step 4: Under high-speed stirring at (11000±300) r / min, add 20g KCl to the second mixture and stir at high speed for 30min to obtain the third mixture;

[0113] Step 5: Under low-speed stirring conditions of (1200±300) r / min, add 486g of weighting material to the third mixture, stir for 30min, mix evenly, and obtain the water-based drilling fluid.

[0114] Example 20

[0115] The weighting material used in this embodiment is barite, with a density of 4.3 g / cm³. 3 .

[0116] Step 1: Measure 400 mL of water, add 0.24 g of anhydrous sodium carbonate and 6 g of bentonite for drilling fluid preparation under high-speed stirring at (11000±300) r / min, stir at high speed for 20 min, stop the stirrer halfway, scrape off the bentonite adhering to the container wall and stirring rod with a glass rod, seal and cure at 25℃±3℃ for 24 h to obtain bentonite-based slurry;

[0117] Step 2: Under high-speed stirring conditions of (11000±300) r / min, 2.7g of Suspension 2# of Example 11 was added to the bentonite-based slurry in sequence. After complete dissolution, 5.4g of Suspension 1# of Example 10 was added. After complete dissolution, the first mixture was obtained. The complete dissolution time was measured when each suspension was added.

[0118] Step 3: Under high-speed stirring conditions of (11000±300) r / min, add 16g of lignite resin SPNH, 12g of sulfonated phenolic resin SMP-2, 12g of sulfonated asphalt FT-3, 6g of plugging agent FDM, 6g of plugging agent FDFT-1, and 12g of drilling fluid lubricant RH220 to the first mixture in sequence to obtain the second mixture. After each material is added, the mixture should be stirred at high speed for 10 minutes before adding the next material.

[0119] Step 4: Under high-speed stirring at (11000±300) r / min, add 20g KCl to the third mixture and stir at high speed for 30min to obtain the third mixture;

[0120] Step 6: Under high-speed stirring at (11000±300) r / min, add 8g of ultrafine calcium carbonate to the third mixture and stir at high speed for 10min to obtain the fourth mixture;

[0121] Step 7: Under low-speed stirring conditions of (1200±300) r / min, add 1795g of weighting material to the third mixture, stir for 30min, mix evenly, and obtain the water-based drilling fluid.

[0122] Comparative Example 11

[0123] The weighting material used in this embodiment is barite, with a density of 4.3 g / cm³. 3 .

[0124] Step 1: Measure 400 mL of water, add 0.64 g of anhydrous sodium carbonate and 16 g of bentonite for drilling fluid preparation under high-speed stirring at (11000±300) r / min, stir at high speed for 20 min, stop the stirrer halfway, scrape off the bentonite adhering to the container wall and stirring rod with a glass rod, seal and cure at 25℃±3℃ for 24 h to obtain bentonite-based slurry;

[0125] Step 2: Under high-speed stirring conditions of (11000±300) r / min, 0.8 g of zwitterionic polymer FA367 was added to the bentonite-based slurry in sequence. After complete dissolution, 2.8 g of polyanionic cellulose was added. After complete dissolution, 2.4 g of hydrolyzed polyacrylonitrile ammonium salt with a degree of hydrolysis of 50% and a relative molecular mass of 10,000 was added. After complete dissolution, the first mixture was obtained. The complete dissolution time of each water-soluble polymer was measured when it was added.

[0126] Step 3: Under high-speed stirring conditions of (11000±300)r / min, add 6g of drilling fluid lubricant RH220 to the first mixture, and stir at high speed for 10min to obtain the second mixture;

[0127] Step 4: Under high-speed stirring at (11000±300) r / min, add 20g KCl to the second mixture and stir at high speed for 30min to obtain the third mixture;

[0128] Step 5: Under low-speed stirring conditions of (1200±300) r / min, add 486g of weighting material to the third mixture, stir for 30min, mix evenly, and obtain the water-based drilling fluid.

[0129] Comparative Example 12

[0130] The weighting material used in this embodiment is barite, with a density of 4.3 g / cm³. 3 .

[0131] Step 1: Measure 400 mL of water, add 0.24 g of anhydrous sodium carbonate and 6 g of bentonite for drilling fluid preparation under high-speed stirring at (11000±300) r / min, stir at high speed for 20 min, stop the stirrer halfway, scrape off the bentonite adhering to the container wall and stirring rod with a glass rod, seal and cure at 25℃±3℃ for 24 h to obtain bentonite-based slurry;

[0132] Step 2: Under high-speed stirring conditions of (11000±300) r / min, 1.2g of zwitterionic polymer FA367 was added to the bentonite-based slurry in sequence. After complete dissolution, 2.8g of polyanionic cellulose was added and dissolved completely to obtain the first mixture. The complete dissolution time of each water-soluble polymer was measured when it was added.

[0133] Step 3: Under high-speed stirring conditions of (11000±300) r / min, add 16g of lignite resin SPNH, 12g of sulfonated phenolic resin SMP-2, 12g of sulfonated asphalt FT-3, 6g of plugging agent FDM, 6g of plugging agent FDFT-1, and 12g of drilling fluid lubricant RH220 to the first mixture in sequence to obtain the second mixture. After each material is added, the mixture should be stirred at high speed for 10 minutes before adding the next material.

[0134] Step 4: Under high-speed stirring at (11000±300) r / min, add 20g KCl to the third mixture and stir at high speed for 30min to obtain the third mixture;

[0135] Step 6: Under high-speed stirring at (11000±300) r / min, add 8g of ultrafine calcium carbonate to the third mixture and stir at high speed for 10min to obtain the fourth mixture;

[0136] Step 7: Under low-speed stirring conditions of (1200±300) r / min, add 1795g of weighting material to the third mixture, stir for 30min, mix evenly, and obtain the water-based drilling fluid.

[0137] Preparation of water-based fracturing fluid:

[0138] Example 21

[0139] Step 1: Add approximately 500 mL of deionized water to a 1000 mL beaker. While stirring at 400 rpm, add 0.058 g of FeCl3 and stir until dissolved. Then add 2.25 g of CaCl2 and 1.442 g of MgCl2 and stir until dissolved. Add 26.25 g of NaCl. Once the added salts have completely dissolved and formed a homogeneous liquid, transfer the solution to a 1000 mL volumetric flask. Rinse the beaker three times with deionized water and transfer all the rinsing solution to the volumetric flask. Add deionized water to bring the volume to 1000 mL to obtain the first mixture.

[0140] Step 2: Measure 500 mL of the first mixture, add 0.6 g of the suspension #4 from Example 13 at (400±5) r / min, mix thoroughly to obtain the water-based fracturing fluid. Measure the complete dissolution time when the suspension is added.

[0141] Example 22

[0142] Measure 500 mL of distilled water and pour it into the Wu Yin mixer. Adjust the mixer speed until the liquid forms a vortex that can be seen at the top of the agitator blades. Then add 10 g of the suspension #5 from Example 14, and adjust the speed to ensure it remains in a vortex state. Continue stirring for 5 minutes to form a homogeneous solution. Stop stirring, pour the solution into a beaker, cover it, and place it in a 30°C water bath for 4 hours to obtain the water-based fracturing fluid. Measure the complete dissolution time when the suspension is added.

[0143] Comparative Example 13

[0144] Step 1: Add approximately 500 mL of deionized water to a 1000 mL beaker. While stirring at 400 rpm, weigh 0.058 g of FeCl3 and stir until dissolved. Then add 2.25 g of CaCl2 and 1.442 g of MgCl2 and stir until dissolved. Add 26.25 g of NaCl and wait until the added salts are completely dissolved to form a homogeneous liquid. Transfer the solution to a 1000 mL volumetric flask and rinse the beaker three times with deionized water. Transfer all the rinsing solution to the volumetric flask and add deionized water to bring the volume to 1000 mL to obtain the first mixture.

[0145] Step 2: Measure 500 mL of the first mixture, add 0.28 g of hydrolyzed polyacrylamide with a degree of hydrolysis of 30% and a relative molecular mass of 3 million at (400±5) r / min, mix thoroughly to obtain the water-based fracturing fluid. Measure the complete dissolution time of the hydrolyzed polyacrylamide upon addition.

[0146] Comparative Example 14

[0147] Measure 500 mL of distilled water and pour it into a Wu Yin mixer. Adjust the mixer speed until the liquid forms a vortex that is visible at the top of the agitator blades. Then add 3.75 g of hydroxypropyl guar gum and adjust the speed to maintain a vortex state. Continue stirring for 5 minutes to form a homogeneous solution. Stop stirring, pour the solution into a beaker, cover, and place in a 30°C water bath for 4 hours to obtain the water-based fracturing fluid. Measure the complete dissolution time after adding the material.

[0148] Performance testing

[0149] (1) Viscosity determination of dispersants and suspensions

[0150] Measurement method: Transfer the dispersants of Examples 1 to 9 and Comparative Examples 1 to 5, or the suspensions of Examples 10 to 18 and Comparative Examples 6 to 10, into the sample cup of a direct-reading viscometer, and measure the reading θ at 100 r / min. 100 Viscosity is calculated using the following formula:

[0151] AV = θ 100 ×3

[0152] The results are shown in Table 1.

[0153] (2) Sedimentation stability of suspension

[0154] Measurement method: Pour the suspensions prepared in Examples 10 to 18 and Comparative Examples 6 to 10 into a 50 mL graduated cylinder, place at room temperature for 30 days, and record the height of the supernatant.

[0155] The results are shown in Table 1.

[0156] Table 1 Performance Evaluation of Dispersants and Suspensions

[0157]

[0158]

[0159] (3) Performance testing of water-based drilling fluids

[0160] Test method: The performance of the water-based drilling fluids prepared in Examples 19 and 20 and Comparative Examples 11 and 12 was determined according to GB / T 16783.1-2014 "Field testing of drilling fluids for the oil and gas industry - Part 1: Water-based drilling fluids". The results are shown in Table 2.

[0161] Table 2 Drilling Fluid Properties

[0162] Performance indicators Example 19 Example 20 Comparative Example 11 Comparative Example 12 Dissolution time of suspension #2, s 55 55 — — Dissolution time of suspension #1, s 50 50 — — Dissolution time of suspension #7, s 45 — — — Dissolution time of zwitterionic polymers, s — — 1800 1800 Dissolution time of polyanionic cellulose, s — — 1500 1500 Dissolution time of hydrolyzed polyacrylonitrile ammonium salt, s — — 1000 1000 <![CDATA[Density, g / cm 3 > 1.38 2 1.38 2 Initial shear force 3 4 3 4 Final shear force 8 10 7.5 10 Apparent viscosity, mPa·s 31 51 30.5 52 Plastic viscosity, mPa·s 21 43 21 44 Dynamic shear force, Pa 10 9 9.5 8 Medium pressure filtration loss / mL 4.4 3.2 4.6 3.4 High-temperature and high-pressure filtration loss (130℃) / mL — 8.6 — 8.8

[0163] (4) Measurement of apparent viscosity of water-based fracturing fluid

[0164] Measurement method: The water-based fracturing fluids prepared in Examples 21 and 22 and Comparative Examples 13 and 14 were transferred into the sample cup of a direct-reading viscometer, and the reading θ at 100 r / min was measured. 100 Viscosity is calculated using the following formula:

[0165] AV = θ 100 ×3

[0166] The results are shown in Table 3.

[0167] (5) Indoor drag reduction rate determination of water-based fracturing fluid

[0168] Add the required amount of clean water to the storage tank of the pipe friction tester (reference pipe friction tester inner diameter 15.8mm, displacement 90±3L / min), start the circulation, and slowly adjust the speed of the power pump to fill the entire test pipeline with the test liquid. Adjust the displacement according to the set parameters and read the value for 4000 seconds. -1 The frictional resistance of the water under shear rate was recorded as data N1.

[0169] Clean the equipment pipelines, filling the entire test pipeline with the water-based fracturing fluids prepared in Examples 21 and 22 and Comparative Examples 13 and 14. Adjust the flow rate as set and read the data for 4000 seconds. -1 The drag reduction water friction at the shear rate was recorded as data N2.

[0170] The drag reduction rate is calculated using the following formula:

[0171]

[0172] In the formula:

[0173] DR—Resistance reduction rate of indoor water to clean water, %;

[0174] N1—Frictional resistance of clean water flowing through the pipeline, kPa / m;

[0175] N2 — Frictional resistance of water flowing through the pipeline, kPa / m

[0176] 1.12 — Drag reduction correction coefficient.

[0177] The results are shown in Table 3.

[0178] (6) pH value measurement of water-based fracturing fluid

[0179] The pH values ​​of the water-based fracturing fluids prepared in Examples 21 and 22 and Comparative Examples 13 and 14 were determined using precision pH test paper.

[0180] Table 3 Fracturing Fluid Properties

[0181]

[0182] As shown in Table 1, the dispersants prepared in Examples 1 to 9 of the present invention can transform powdered water-soluble polymer products into a suspension with high dispersibility, high stability, high solid content and good fluidity. However, the dispersants prepared in Comparative Examples 1 to 5, which are made by reducing some raw materials, have a large volume of clear liquid in the upper layer of the suspension, indicating that the suspension has poor sedimentation stability.

[0183] As shown in Tables 2 and 3, when the suspensions prepared in Examples 10, 11, and 16 of this invention are used to prepare water-based drilling fluids in Examples 19 and 20, and when the suspensions prepared in Examples 13 and 14 are used to prepare water-based fracturing fluids in Examples 21 and 22, the dissolution rate is fast, fisheyes do not form during the preparation process, and the preparation time for water-based drilling fluids and water-based fracturing fluids is saved. In contrast, in Comparative Examples 11 to 14, the water-soluble polymers have a long dissolution time and are prone to forming fisheyes during the preparation process.

[0184] As shown in Tables 2 and 3, the water-based drilling fluids prepared in Example 19 and Comparative Example 11 exhibit consistent performance; the water-based drilling fluids prepared in Example 20 and Comparative Example 12 exhibit consistent performance; the water-based fracturing fluids prepared in Example 21 and Comparative Example 13 exhibit consistent performance; and the water-based fracturing fluids prepared in Example 22 and Comparative Example 14 exhibit consistent performance. This indicates that the modification of the water-soluble polymer material into a suspension by the dispersant of this invention has no impact on the performance of the prepared water-based drilling fluids and water-based fracturing fluids. Furthermore, it can improve the dissolution rate of the water-soluble polymer, overcome the shortcomings of water-soluble polymers during use, and improve the utilization efficiency of water-soluble polymer products.

[0185] In summary, through comparative analysis of the examples and comparative examples, the dispersant of the present invention produces better technical effects, which is the result of the synergistic effect between the components in the dispersant of the present invention.

[0186] While the present invention has been described with reference to specific embodiments, those skilled in the art will understand that various changes can be made without departing from the true spirit and scope of the invention. Furthermore, numerous modifications can be made to the subject, spirit, and scope of the invention to suit specific situations, materials, material compositions, and methods. All such modifications are included within the scope of the claims of the present invention.

Claims

1. A dispersant for water-soluble polymer suspensions, comprising linoleic acid diethanolamide, sodium dodecyl sulfate, isotridecyl alcohol polyoxyethylene ether, triethylene glycol butyl ether, a thickener, and a solvent; Based on 100 parts by weight of the dispersant, the composition includes 1 to 2 parts of linoleic acid diethanolamide, 1 to 3 parts of sodium dodecyl sulfate, 2 to 3 parts of isomeric tridecyl alcohol polyoxyethylene ether, 0.4 to 0.6 parts of triethylene glycol butyl ether, 1 to 3 parts of the thickening agent, and the remainder being solvent. The viscosity enhancer is organic bentonite; The solvent is white oil.

2. The dispersant according to claim 1, characterized in that, The solvent is at least one of No. 3 white oil, No. 5 white oil and No. 15 white oil.

3. A suspension comprising a water-soluble polymer and a dispersant as described in claim 1 or 2.

4. The suspension according to claim 3, characterized in that, The water-soluble polymer is at least one of xanthan gum, sodium carboxymethyl cellulose, polyanionic cellulose, hydrolyzed polyacrylamide, hydrolyzed polyacrylonitrile salt, zwitterionic polymer FA367, and guar gum.

5. The suspension according to claim 3, characterized in that, The water-soluble polymer is potassium polyacrylamide.

6. The suspension according to claim 4, characterized in that, The degree of hydrolysis of the hydrolyzed polyacrylamide is 20% to 40%, and the relative molecular weight of the hydrolyzed polyacrylamide is 100,000 to 5,000,000.

7. The suspension according to claim 6, characterized in that, The degree of hydrolysis of the hydrolyzed polyacrylamide is 30%, and the relative molecular weight of the hydrolyzed polyacrylamide is 3 million.

8. The suspension according to claim 4, characterized in that, The hydrolyzed polyacrylonitrile salt is hydrolyzed polyacrylonitrile ammonium salt and / or hydrolyzed polyacrylonitrile potassium salt.

9. The suspension according to claim 4, characterized in that, The degree of hydrolysis of the hydrolyzed polyacrylonitrile salt is 50% to 60%, and the relative molecular weight of the hydrolyzed polyacrylonitrile salt is 10,000 to 100,000.

10. The suspension according to claim 9, characterized in that, The degree of hydrolysis of the hydrolyzed polyacrylonitrile salt is 50%, and the relative molecular weight of the hydrolyzed polyacrylonitrile salt is 10,000.

11. The suspension according to claim 4, characterized in that, The guar gum is at least one of natural guar gum, hydroxypropyl guar gum, carboxymethyl guar gum, and hydroxypropyl carboxymethyl guar gum.

12. The suspension according to claim 3, characterized in that, The ratio of the water-soluble polymer to the dispersant is (30 to 55):

50.

13. A drilling fluid comprising a suspension as described in any one of claims 3 to 12.

14. The drilling fluid according to claim 13, characterized in that, The drilling fluid is a water-based drilling fluid.

15. A fracturing fluid comprising the suspension as described in any one of claims 3 to 12.

16. The fracturing fluid according to claim 15, characterized in that, The fracturing fluid is a water-based fracturing fluid.

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