111results about How to "Good temperature and shear resistance" patented technology

The invention discloses a seawater-based fracturing fluid for fracturing a sea high-temperature oil-gas reservoir and relates to the technical field of cross-linked gel fracturing fluid. The seawater-based fracturing fluid comprises a base solution, a cross-linking agent and a thickening agent, wherein the base solution comprises the components (in percentage by weight) in terms of the weight of the prepared seawater-based fracturing fluid total solution as follows: 0.3%-0.8% of thickening agent, 0.1%-0.3% of pH regulating agent, 0.1%-0.5% of discharge aiding agent and the balance being seawater; relative to the mass fraction of the base solution, the cross-linking agent is 0.4%-0.6%; and the thickening agent refers to guar gum, carboxy-methyl hydroxypropyl guar gum, hydroxypropyl guar gum, fenugreek gum or sesbania gum. The seawater-based fracturing fluid is adopted, so that the dissolving speed of the thickening agent is quick, and therefore, direct mixing and continuous constructing can be realized, and therefore, the seawater-based fracturing fluid is in particular suitable for the fracturing construction of the sea high-temperature oil-gas reservoir. Meanwhile, the fracturing fluid can be continuously sheared for 90 minutes under the conditions of 150 DEG C and 170s<-1>, so that the viscosity is kept to be 70mPa.s or more.

The invention provides high-temperature resistant CO2 foam cleaning and associated fracturing fluid and a preparation method and application thereof. The high-temperature resistant CO2 foam cleaning and associated fracturing fluid comprises a fracturing fluid base solution, a cross-linking agent, a gel breaker and liquid CO2, wherein the cross-linking agent and the gel breaker account for 0.3%-0.8% and 0-0.05% of the fracturing fluid base solution in parts by weight separately; and the liquid CO2 accounts for 30%-70% of total volume of the CO2 foam cleaning and associated fracturing fluid. The high-temperature resistant CO2 foam cleaning and associated fracturing fluid provided by the invention has the characteristics of being few in additive types, simple in preparation, controllable in crosslinking, low in residue, low in damage, low in friction, high in foaming efficiency, high in flowback rate and resistant to high temperature.

The invention relates to a fracturing fluid which comprises a base fluid A and a base fluid B, wherein the base fluid A is prepared from a thickening agent, a hydrotropy thickening agent, a clay stabilizer, a discharge aiding agent, a sterilizing agent, a demulsifying agent, a low-temperature activator and water; the base fluid B is prepared from a low-molecular weight polymer, the clay stabilizer, the discharge aiding agent, the sterilizing agent, the demulsifying agent, the low-temperature activator and the water. When fracturing construction is carried out, the base fluid A and the base fluid B are mixed in proportion, the low-molecular weight polymer and a thickening agent molecule are mutually wound in a stirring process to form a certain space reticular structure for effective thickening, and the hydrotropy thickening agent compresses a winding structure through electric repulsion so that a gel is further thickened and forms good solid carrying capacity; the shearing is carried out at 50 DEG C and 170S-1,3.5MPa for 60 minutes, the viscosity is more than 50 mPa.s, an oxidized type gel breaker is added according to the proportion of 0.01%-0.20% in a wedge shape, the gel can be thoroughly broken within 2 hours, and the viscosity of gel breaking liquid is less than 5 mPa.s.

The invention provides high-temperature-resistant ground cross-linked acid liquor. The acid liquor comprises the following components in percentage by mass: 15-28 weight percent of acid, 0.4-1.0 weight percent of polyacrylamide polymer, 0.1-0.5 weight percent of aldehyde cross-linking agent, 0.05-0.25 weight percent of phenol cross-linking agent, 0.05-0.02 weight percent of crosslinking promoter, 0.5-2.0 weight percent of corrosion inhibitor, 0.5-2.0 weight percent of ferric ion stabilizer, 0.01-0.1 weight percent of ammonium persulfate and the balance of water, wherein the acid is calculated based on pure substances. The invention also provides a method for preparing the high-temperature-resistant ground cross-linked acid liquor. Industrial raw materials which are low in toxicity and low in price are taken as cross-linking agents and cross-linking promoter, the toxicity of the cross-linking agents can be reduced, the process for preparing the high-temperature-resistant ground cross-linked acid liquor is simple, further synthesis is not needed, the field operability is high, the cost is effectively reduced, and application of acid fracturing is further widened.

The invention discloses a dry fracturing fluid anti-drag thickening agent and a preparation method thereof. The dry fracturing fluid anti-drag thickening agent comprises, by mass, 45-65% of carbon-dioxide-philic solvent, 10-15% of oil-soluble solvent, 5-10% of hydrotropy monomer, 15-20% of tackifier monomer, 3-5% of structural monomer, 1-3% of super-carbon-oxide-philic monomer, 0.5-1% of oil-soluble chain transfer agent and 0.5-1% of oil-soluble initiator. The dry fracturing fluid anti-drag thickening agent is convenient to prepare and use, has super-fast solubility, efficient thickening performance, excellent temperature and shear resistance capacity, excellent sand carrying capacity and efficient drag reduction performance.

The invention relates to a high-temperature water base fracturing fluid and a preparation method thereof. The fracturing fluid is prepared from the following additives by weight: 0.45-1.0% of a thickening agent, 0.6-1.5% of a clay stabilizer, 0.6-1.5% of an emulsion breaking cleanup additive, 0.01-0.03% of a gel breaking agent, 0.6-2.0% of a crosslinking agent and the balance of sea water, wherein the total sum weight percentages of the components is 100%. The fracturing fluid has the advantages of good sand carrying capability, good heat resistant and shearing resistant performances, good compatibility with formation fluid and small reservoir damage; seawater can be used directly to prepare the solution; and conventional liquid dispensing equipment and process are employed to solve the problem of lack of freshwater in offshore fracturing construction. The invention improves working efficiency of offshore fracturing, reduces the cost, and lays the foundation for the large-scale offshore fracturing operation.

The invention discloses a gel fracturing fluid prepared from oilfield sewage and a preparation method thereof. The gel fracturing fluid comprises the following components in percentage by weight: 0.01-1% of water quality regulator, 0.01-0.5% of bactericide, 0.1-0.8% of thickener, 0.1-0.5% of crosslinking agent, 0.01-0.5% of viscosity breaker and the balance of oilfield sewage. The gel fracturing fluid prepared from oilfield sewage has favorable temperature resistance and shear resistance, and satisfies the demands for on-site construction. The gel fracturing fluid prepared from oilfield sewage relieves the demands of hydraulic fracturing for water resources, and solves the problem of treatment of oilfield sewage. The gel fracturing fluid prepared from oilfield sewage has the advantages of favorable clay swelling resistance and low formation damage rate, thereby reducing the use of the antiswelling agent and saving the cost. The gel fracturing fluid prepared from oilfield sewage has wide formation application range, avoids damage to the formations which are sensitive to alkali, acid and the like, has favorable economic benefit and environmental benefit, and is suitable for popularization and application.

The invention discloses a temperature-resistant salt-resistant quick-dissolving thickening agent used for a seawater-based fracturing fluid and a preparation method thereof. The temperature-resistant salt-resistant quick-dissolving thickening agent comprises the following components in percentages by mass: 6% to 8% of acrylic acid, 5% to 6% of sodium hydroxide, 18% to 23% of acrylamide, 1% to 2% of an isolation monomer, 3% to 4% of a functional anion monomer, 3% to 5% of a functional cationic monomer, 4% to 6% of an association intermediate, and 0.4% to 0.8% of an ammonium persulfate-sodium bisulfite redox system or 0.6% to 1.0% of azobisisobutyronitrile which is used as an initiator, with the balance being deionized water. The preparation method for the temperature-resistant salt-resistant quick-dissolving thickening agent comprises the following steps: 1, synthesis of the association intermediate; 2, synthesis of a thickener colloid; and 3, colloid postprocessing. The thickening agent provided by the invention has the following advantages: salt resistance is excellent; the degree of mineralization of a solution has little influence on the rate of swelling; the viscosity-increasing capacity in seawater is strong; antibacterial stability of the solution is strong; the solution has excellent temperature resistance and shearing resistance; and the content of an insoluble substance is extremely small and can not be measured with a conventional method, so the damage of residues on reservoir strata is almost eliminated.

The invention relates to guar gum cleaning fracturing fluid with micro residue and weak damage. The guar gum cleaning fracturing fluid with micro residue and weak damage is composed of base liquid, a cross-linking agent and a gel breaker, the base liquid is composed of hydroxypropyl guar gum, a cleanup additive, an anti-swelling stabilizing agent, a fracturing bactericide, a fracturing de-emulsifier, a scale inhibitor and water. According to the invention, a guar gum multinucleated cross-linking agent with low amount is used, delay crosslinking effect is strong, guar gum concentration is greatly reduced, glue breaking residue amount is reduced, a multifunctional scale inhibitor is cooperated for preventing fouling generated by water used for fracturing liquid and stratum water, a selective polymer fracturing catalyst capable of thoroughly breaking glue and no generating sulfate radical is selected, liquid viscosity and residue content are reduced, the surface tension of the gel breaker after gel is broken is lower, the gel breaker is easily discharged, the formed guar gum multinucleated cross-linking agent has good temperature and shearing sustainability, and excellent proppant carrying capacity.

An emphasized fracturing liquid formula consists of water 500 proportion, emphasizing agent 180-483 proportion, gelatinizer hydroxypropyl guar gum 2-3 proportion, pH value adjuster sodium carbonate 0.8-1 proportion, pH value adjuster sodium hydrate 0.15-0.27 proportion, auxiliary 3.0-3.3 proportion, and emphasized fracturing liquid density is between 1.25-1.5g/cm3. It can be used to increase liquid column pressure in well and decrease construction pressure on well opening and finish oil-well fracture of deep well, super-deep well, abnormal high-pressure well and realize storage-layer transformation.

The invention relates to a vegetable gelatin fracturing fluid and a preparation method thereof. The fracturing fluid used by the oil field at present mostly adopts hydroxypropyl guar gum as a thickening agent, and has high cost. The preparation method for the vegetable gelatin fracturing fluid comprises the following steps of: reacting water, glycerol and borax to obtain an organic-boron cross-linking agent; reacting butyl titanate, triethanolamine and glycerol to obtain an organic titanium high-temperature stabilizer; mixing water with konjac glucomannan to obtain a base solution; and adding the organic-boron cross-linking agent and the organic titanium high-temperature stabilizer to prepare the vegetable gelatin fracturing fluid. The fracturing fluid provided by the invention adopts the konjac glucomannan as the thickening agent which has good viscosity and temperature and shearing resistance, adopts the self-prepared organic-boron cross-linking agent which has high cross-linking density and strength, and is additionally added with the organic titanium high-temperature stabilizer, so that the konjac glucomannan fracturing fluid has good temperature and shearing resistance. Moreover, the content of the rubber-crushed residues is extremely low, and the damage degree to the earth surface is extremely low.

The invention relates to a high-density fracturing fluid capable of slowing crosslinking and resisting high temperature. The fracturing fluid is composed of a stock solution and a crosslinking liquid with a volume ratio of 10 : 1, wherein the stock solution comprises, by weight percent, 0.5-0.65 % of hydroxypropyl guar gum, 8-45 % of a weighting agent A, 6-30 % of a weighting agent B, 0.5-2 % of a ZJ-07 cleanup additive, 0.01-0.04 % of a pH-value conditioning agent A, and the balance being water; the crosslinking liquid comprises, by weight percent, 0.5-3 % of a cross-linking agent YGB, 1-2 % of a cross-linking agent HT, 0.1-0.4 % of a pH-value conditioning agent B, 0-0.35 % of a gel breaker and the balance being water. The fracturing fluid is good in temperature-resistance and shearing-resistance performances, wherein the temperature-resistance performance is up to 145 DEG C, and a viscosity is still more than 120 Pa*S after the liquid is sheared for 90 minutes under 145 DEG C and 170 S<-1>.

The invention provides a guar gum grafted copolymer nanocomposite gel fracturing fluid and a preparation method thereof. The fracturing fluid comprises the following components in percentage by mass:0.4-1.2% of a guar gum grafted copolymer thickening agent, 0.05-0.5% of a nanomaterial and 0.2-1% of a cross-linking agent, with the balance being water. According to the invention, guar gum or a derivative thereof and acrylamide monomers are used as raw materials to synthesize a guar gum graft copolymer, the guar gum graft copolymer is used as the thickening agent, a nanomaterial dispersion liquid is added, and the nanocomposite gel fracturing fluid is prepared under the action of the cross-linking agent. Hydrophilic flexible polymer branched chains are introduced to semi-rigid macromolecularchains of guar gum, so mutual entanglement and adsorption between the guar gum and the nanomaterial are facilitated, the compatibility of the guar gum and the nanomaterial can be greatly improved, and interaction between the nanomaterial and a polymer matrix is further improved; and the prepared nanocomposite gel fracturing fluid has better temperature resistance, shearing resistance, sand carrying property and filtrate loss reduction property.

The invention relates to a boron cross-linking agent for a fracturing fluid in the technical field of oil-gas field development and an ultralow hydroxypropylguar gum concentration fracturing fluid prepared from the boron cross-linking agent. The cross-linking agent comprises the following ingredients (by weight): 20-30 parts of an amide compound, 40-60 parts of water, 50-100 parts of glycol, 13-25 parts of boric acid, 20-30 parts of n-butanol and 30-40 parts of an aldehyde compound. The ultralow hydroxypropylguar gum concentration fracturing fluid contains (by volume): 98.6-98.9 parts of a hydroxypropylguar gum aqueous solution and 0.6-0.9 part of the boron cross-linking agent for a fracturing fluid. By the use of the cross-linking agent and under the precondition of guaranteeing performance of the fracturing fluid, hydroxypropylguar gum concentration can be reduced by more than 30%, thus lowering costs of the fracturing fluid and decreasing damage to the bottom layer.

The invention discloses a low-concentration hydroxypropyl guanidine gum fracturing fluid and a preparation method thereof. The fracturing fluid comprises the following components in parts by weight: 100 parts of a hydroxypropyl guanidine gum aqueous solution, and 0.1-0.5 part by weight of a nano silicon dioxide organic boron cross-linking agent, wherein the weight concentration of the hydroxypropyl guanidine gum in the hydroxypropyl guanidine gum aqueous solution is 0.15-0.5%, the nano silicon dioxide organic boron cross-linking agent is nano silicon dioxide with the surface modified with an organic phenylboronic acid group, and the organic boric acid group and the nano silicon dioxide are combined in a covalent bond mode through amino. According to the invention, the fracturing fluid system with low hydroxypropyl guanidine gum concentration is formed, effective cross-linking of the fracturing fluid system is achieved under the low hydroxypropyl guanidine gum concentration of 0.15-0.5%, and the fracturing fluid system has good temperature resistance, shearing resistance and filtration performance and can meet fracturing of oil and gas fields at the temperature of 80-170 DEG C.

The invention relates to the technical fields of oilfield chemistry, reservoir reconstruction and fracturing production increase and particularly relates to multifunctional reservoir reconstruction liquid and a preparation method therefor. The weakly-acidic multifunctional reservoir reconstruction liquid provided by the invention contains a base solution for the reservoir reconstruction liquid, a structure reinforcing agent for the reservoir reconstruction liquid and ammonium persulfate, wherein the base solution for the reservoir reconstruction liquid is prepared from the following ingredients in percentage by weight: 0.3-0.6% of thickening agent for the reservoir reconstruction liquid, 0.3-0.4% of regulator for the reservoir reconstruction liquid, 1% of potassium chloride and the balance of water. The multifunctional reservoir reconstruction liquid and the preparation method therefor have the following advantages that the multifunctional reservoir reconstruction liquid has efficient swelling resistance and a precipitate generation preventing function, and damage caused by the action between reservoirs and reservoir fluid can be effectively lowered; the viscosity is relatively low, so that seam height is effectively controlled; the viscous elasticity is excellent, so that the sand carrying performance of a system is improved; and the multifunctional reservoir reconstruction liquid has the characteristics that the damage is low, no residue is caused, and flowback fluid can be recovered and reused.

The invention relates to a phosphate anhydrous fracturing fluid gelling agent and a preparation method thereof. The preparation method comprises the following steps: by taking phosphoric acid, phosphorus pentoxide and C12-C18 alcohol as raw materials, reacting for 4-6 hours at a temperature of 60-70 DEG C so as to obtain a monoalkyl phosphate ester, wherein the molar ratio of phosphoric acid to phosphorus pentoxide to the C12-C18 alcohol is (1.3 to 1.3 to 1)-(1.1 to 1.1 to 1); and reacting the monoalkyl phosphate ester with a mixed alcohol of propyl alcohol or/and butyl alcohol, amyl alcohol, hexyl alcohol or/and capryl alcohol so as to obtain a dialkyl phosphate ester, wherein the molar ratio of the mixed alcohol to the monoalkyl phosphate ester is (4 to 1)-(2 to 1), and the mixed alcohol comprises 7-10% of propyl alcohol and/or butyl alcohol, 20-40% of amyl alcohol, and 50-60% of hexyl alcohol or/and capryl alcohol in percentage by mass. The phosphate gelling agent is good in flowability, suitable for continuous fracturing construction, and low in cost, and can, with short-carbon-chain alkanes, form an anhydrous fracturing fluid with a viscosity of 90-140 mPa.s.

The invention discloses an acid polymer weighted fracture fluid and a preparation method thereof, wherein the acid polymer weighted fracture fluid comprises a base fluid and a crosslinked fluid, the base fluid comprises components with percentage by quality: weighting agents 20%-50%, polymer thickening agent 0.8%-1.20% and discharge aiding agent 0.2%-0.5%, and the allowance is water. The crosslinked fluid comprises an acid polymer delayed crosslinked agent and an acid polymer crosslinked agent, wherein the weight radio of the acid polymer delayed crosslinked agent and the acid polymer crosslinked agent is (1.5-2.5): (3.5-5), and the quality of the crosslinked fluid is 0.6%-0.8% of the quality of the base fluid. The acid polymer weighted fracture fluid achieves to adjust density in 1.10g/cm3-1.50g/cm3, meets the density demands for the scene, improves pressure of fluid columns in shafts, reduces construction pressure of wellheads, and is suitable to remould fracture reservoirs of deep wells, superdeep wells, abnormal high pressure wells and dense wells.

The invention discloses a high temperature resistant nanometer zirconium boron cross-linking agent and a preparation method thereof. The preparation method of the cross-linking agent is characterizedin that (1) a lauryl sodium sulfate solution and a zirconium oxychloride octahydrate solution are respectively prepared; (2) the zirconium oxychloride octahydrate solution is dropwise added into the lauryl sodium sulfate solution; then, cyclohexane is added; next, the mixed solution is put into a reaction kettle; a sodium hydroxide solution is added; reaction is performed for 24h to obtain a nanometer zirconium dioxide emulsion; (3) glycerol, borax, beta-diketone and triethanolamine are sequentially added into the nanometer zirconium dioxide emulsion; reaction is performed under the conditionthat the pH value is 10, so that the nanometer zirconium boron cross-linking agent is prepared. The nanometer zirconium boron cross-linking agent prepared by the method has excellent temperature resistant and shearing resistant performance; the cost is low; the gel breaking and flowback are easy.

The invention provides a method for preparing an acid liquid system. The method comprises the following steps: 1) adding a thickening agent into a hydrochloric acid solution at a first stirring speed,and stirring at a second stirring speed to obtain a first acid liquid; 2) sequentially adding an iron ion stabilizer, a corrosion inhibitor and a demulsification cleanup additive into the first acidliquid, uniformly stirring at a third stirring speed, and standing to obtain a base solution; and 3) adding a tackifier into the base solution, and stirring at a fourth stirring speed to obtain the acid liquid system.

The invention discloses preparation of a sulfonic acid amphoteric double-ion viscoelastic surfactant and application in fracturing fluid. The preparation method includes: firstly subjecting long-chainaliphatic tertiary amine and epichlorohydrin to quaternization reaction on obtain an intermediate DNPC; and then reacting the DNPC with sodium sulfanilate to obtain the sulfonic acid amphoteric double-ion surfactant VBS. The preparation method disclosed by the invention has the characteristics of high yield, no industrial waste residue and environmental friendliness. In addition, the sulfonic acid amphoteric double-ion viscoelastic surfactant VBS is compounded with an inorganic salt counter ion to obtain a clean fracturing fluid system with excellent rheological properties. The system has theadvantages of strong sand suspending performance, simple on-site preparation, automatic gel breaking and small stratum damage. After 90min of shearing at 90DEG C and under 170s<-1>, the 10mmol/L VBSfracturing fluid system can maintain the viscosity at about 50mPa.S, and can meet the viscosity requirement of site construction for clean fracturing fluid.

The invention relates to guar gum clean fracturing fluid for an oil well and a preparation method of the guar gum clean fracturing fluid. The guar gum clean fracturing fluid is composed of the following components in percentage by mass: 0.25 to 0.28% of hydroxypropyl guar gum; 0.25 to 0.40% of multi-effect fracturing auxiliary agent; 0.015 to 0.04% of chelating agent; 0.20 to 0.35% of cross-linking agent; 0.01 to 3% of gel breaker; and the balance being water. The selected multi-effect fracturing additive has good foaming capacity and is beneficial to flowback, meanwhile, a water locking effect can be reduced through low surface and interface tension, reservoir clay expansion can be prevented, multiple effects can be realized with such an agent is achieved, the overall performance of the fracturing fluid is improved, and operation is easy. The chelating agent improves the compatibility of the fracturing fluid and formation water; and the gel breaker can solve the problem of corrosion of ammonium persulfate to equipment. The guar gum clean fracturing fluid system is low in use concentration and good in temperature resistance and shearing resistance, and has the advantages of low residue, small damage to a reservoir stratum, and bright application and popularization prospect.

The invention discloses a preparation method of a surfactant fracturing fluid capable of recycling. The preparation method comprises the following steps: after uniformly mixing organic acid with N,N-dimethyl-1,3-propane diamine compound, heating to 150 to 180 DEG C for carrying out a reaction for 4 to 6 hours, cooling to room temperature, and carrying out a reaction to obtain an intermediate; uniformly mixing the intermediate with a dihalide in an ethanol water solution, stirring and warming to 60 to 90 DEG C, carrying out a reaction for 3 to 5 hours, and cooling to room temperature to obtaina surfactant; adding 2% to 4% of the surfactant and 1% to 3% of a dihalide water solution into water in sequence in percentage by weight for uniform stirring so as to obtain the surfactant fracturingfluid. The surfactant fracturing fluid is simple in formula and high in temperature resistance and shearing resistance, a chemical gel breaker does not need to be added, gel can be broken when suffering from oil or water, the surfactant fracturing fluid is high in flowback capacity and free of residue, clay can be effectively stabilized, the formation damage is low, a flowback fluid can be recycled through simple treatment, a large quantity of water and additives can be saved, and the cost is reduced.