31results about How to "Meet the requirements of fracturing construction" patented technology

The invention relates to a fracturing fluid system used in an oil and gas field, in particular to a fracturing fluid system of CO2 cleaning foam. The fracturing fluid system comprises the following components in percentage by weight: 0.3-0.8 percent of water-soluble hydrophobic association polymer, 0.25-0.55 percent of rheological auxiliary agent, 0.5-3.0 percent of clay stabilizer, 0.1-0.5 percent of foaming agent, 0.01-0.2 percent of gel breaker, 30.0-80.0 percent of liquid CO2 and the balance of water. Compared with the prior art, in the fracturing fluid system of the CO2 cleaning foam, a cross-linking agent is not needed, the foamability is good, the foam stability is high, the sand-carrying capability is strong, gel breaking is easy to control, no residue is generated after gel breaking, the superficial/interfacial tension of gel-breaking liquid is low, and the damage to the formation is less, and therefore, the fracturing fluid system can be used for fracturing modification of hypoisotonic, low-pressure and water-sensitive storage layers at the temperature of 60-140 DEG C.

The invention relates to a high temperature resistant cleansing emulsion or microemulsion fracturing fluid and a preparation method thereof. The emulsion fracturing fluid is composed of a continuous oil phase, a polymer (I)-containing dispersed water phase and an emulsifier. The preparation method of the emulsion fracturing fluid includes: preparing a mixed solution of the oil phase and the emulsifier, preparing a four-monomer containing water phase, conducting a polymerization reaction in the presence of an initiating agent, and other steps. The product provided in the invention has low apparent viscosity, and can dissolve rapidly. When the emulsion dissolves into gel, the emulsifier can have a synergistic effect with an association polymer, thus further improving and maintaining the viscosity, and helping to prevent leak-off and help flowback. An oxidation gel breaking way is employed for gel breaking, the gel can be completely broken, and the gel breaking solution has low viscosity and contains no residue. The emulsion fracturing fluid is easy to undergo flowback, and has low damage to the stratum.

The invention relates to an ultralow-temperature guanidine gum fracturing fluid comprising 0.3%-0.45% of hydroxypropyl guar gum, 1-15% of KCl, 1-3% of a discharge aiding agent, 0.5-2% of a demulsifying agent, 0.5-2%% of a clay stabilizer, 0.1-0.5% of a fungicide, 0.01-0.03% of a pH value regulator, 0.002-0.008% of an activator, 0.1-0.3% of a crosslinking agent, 0.04-0.1% of a gel breaker, and the balance being water. The using effect of the fracturing fluid can be improved to a great extent, and the fracturing fluid can completely break gel and flow back at a low temperature of 15 DEG C-35 DEG C.

The invention relates to a fracturing fluid thickening agent and preparation and application thereof. The thickening agent is mainly prepared from the following components in percentage by weight: 15-20% of acrylamide monomer, 6-10% of acrylic monomer, 3-6% of sodium carbonate, 3-8% of 2-acrylamide-2-methylpropanesulsonic acid, 1-4% of dimethyldiallylammonium chloride (60% aqueous solution), 0.03-0.08% of potassium persulfate and the balance of water. The preparation comprises the following steps of: adding the acrylic monomer and water into a reaction kettle; starting stirring and slowly adding sodium carbonate, wherein the adding speed is proper when the bubbles generated by the reaction do not overflow out of the reaction kettle; stirring till sufficient dissolution; adding 2-acrylamide-2-methylpropanesulsonic acid, and stirring till sufficient and uniform mixing; adding the acrylamide monomer and dimethyldiallylammonium chloride, and stirring till sufficient dissolution; heating the reaction liquid to 40 DEG C, introducing nitrogen, and performing thermal insulation stirring for 20 minutes; adding potassium persulfate; continuously introducing nitrogen, and stirring for 30 minutes; stopping the stirring, and reacting for 4 hours to obtain gel; and grinding the reaction product, drying and granulating to obtain the thickening agent.

The invention discloses a high-temperature-resistance low-friction weighted clean fracturing fluid which is suitable for high-temperature and high-pressure reservoir reconstruction at 170 DEG C and a preparation method thereof.The fracturing fluid is prepared from, by weight, 0.2%-0.8% of high-temperature-resistance thickening agent, 0.1%-0.8% of system synergist, 0.1%-0.3% of high temperature stabilizer, 0%-42% of weighting agent and the balance fresh water.The high-temperature-resistance low-friction weighted clean fracturing fluid has the following functions and advantages that the weighting agent can be adopted for weighting, and the density is adjustable between 0 and 1.32 g/cm<3>; good temperature-resistance and anti-shearing properties are achieved, and the requirement of high-temperature deep well fracturing construction at 170 DEG C can be met by adjusting a formula; a good resistance reduction property is achieved, pipeline friction resistance can be effectively reduced, and the resistance reduction rate can reach 70%; the fracturing fluid is a fluid with a reversible structure, and the structure damage after high shearing is small; the residue content of the fracturing fluid is decreased to below 10 mg/L, damage to a reservoir and supporting cracks is reduced, the fracturing effect is improved, and the reservoir productivity is increased.

The present invention relates to a gel breaking and emulsion breaking oil-in-water emulsification fracturing fluid, which comprises, by mass, 0.5-0.65% of hydroxypropyl guar gum, 1-15% of KCl, 0.1-2% of OP-10, 0.5-3% of WT-1, 1% of a cleanup additive, 0.5-2% of an emulsion breaker, 0.5-2% of a clay stabilizer, 0.01-0.1% of a bactericidal agent, 0.01-0.03% of sodium hydroxide, 5-40% of diesel fuel, and the balance of water. With the gel breaking and emulsion breaking oil-in-water emulsification fracturing fluid, a use effect of the fracturing fluid can be substantially increased, such that the fracturing fluid can be subjected to complete gel breaking, and emulsion breaking can be performed under the stratum condition.

The invention discloses a nano liquid destroying agent for fracturing fluid and a preparation method thereof. The nano liquid destroying agent for the fracturing fluid is prepared from, by weight, 5.2-16.4% of peroxide, 2.3-10% of a gemini surfactant, 8.4-16.0% of a nonionic emulsifier, 1.9-4.4% of an auxiliary additive and 62.5-78.5% of a solvent; the structure of the nano liquid destroying agentfor the fracturing fluid is that the nonionic emulsifier and the gemini surfactant form a mixed micelle or vesicle having a closed double layer structure, and the peroxide and the inner layer structure constitute an ion pair and are wrapped inside the micelle or vesicle; the mixed micelle or vesicle size of the nano liquid destroying agent is nanometer-scale and specifically is between 15 and 100nanometre. The agent can meet the gel breaking requirements of the polymer fracturing fluid and the silicone fracturing fluid, and has the advantages of good storage stability at room temperature, weak corrosiveness, long storage period and good delayed gel breaking effect.

The invention provides a fracturing fluid and a preparation method thereof. The fracturing fluid comprises vegetable gum, a synergist, a cross-linking agent, an optional clay stabilizer, a cleanup additive, water and an optional bactericide. The fracturing fluid comprises the following components in percentage by mass: 0.2%-0.75% of vegetable gum, 0.1%-10% of a synergist, 0.25%-0.65% of a cross-linking agent, 0-2% of a clay stabilizer, 0.05%-1% of a cleanup additive, 0-0.1% of a bactericide and the balance of water.

The invention provides a polymer acidic cross-linking agent, which is prepared from the following raw materials in percentage by weight: 20-30% of a complexing agent, 0.1-5% of nanoparticles with core-shell structure, 5-10% of a zirconium compound, 1-3% of a stabilizer, 3-5% of a corrosion inhibitor and the balance of deionized water, wherein the nanoparticles with the core-shell structure take sulfide-loaded amorphous alumina as a core and oligomeric chitosan as a shell material, and the particle size of the nanoparticles is 50-500 nm. According to the cross-linking agent, the problem of more residues after gel breaking of a zirconium cross-linking agent is remarkably improved, the flowback rate is remarkably increased, and the damage to a reservoir is remarkably reduced.

The invention discloses a method for preparing fracturing fluid by utilizing polymer type fracturing flow-back fluid, and relates to the technical field of fracturing flow-back fluid reutilization. The invention aims to solve the problem of pollution of fracturing flow-back fluid to the environment and reduce the fracturing construction cost. The method comprises the following steps of: mixing 0.2-0.4 parts of base fluid, 0.002-0.004 parts of a cross-linking agent, 0.00002-0.00005 parts of a gel breaker and 99.6-99.8 parts of fracturing flow-back fluid subjected to reverse osmosis treatment, and fully stirring to obtain fracturing fluid. The base fluid is prepared from 25 parts of guanidine gum, 5 parts of a cleanup additive, 4 parts of a demulsifying agent, 5 parts of sodium carbonate, 1 part of sodium bicarbonate, 50 parts of a liquid clay stabilizer, 3 parts of a defoaming agent, 5 parts of a vegetable gum stabilizer and 3 parts of a sterilizing agent. The method for preparing fracturing fluid by utilizing polymer type fracturing flow-back fluid is obtained.

The invention provides epoxy succinic acid modified mannoside, a preparation method and application thereof, a fracturing fluid cross-linking agent and a fracturing fluid, and relates to the technical field of cross-linking agents. When the epoxy succinic acid modified mannoside with the structure as shown in the formula I provided by the invention can be used as a ligand to be applied to a fracturing fluid cross-linking agent, adjacent carboxyl and hydroxyl of the epoxy succinic acid modified mannoside can form a five-membered ring with a stable structure with central particles (zirconium ions, titanium ions, aluminum ions or boron atoms); compared with gluconate and modified gluconic acid, the alpha-methyl-D-mannoside has a better chelation effect and longer delayed cross-linking time, and has a very good application prospect in the aspects of preparation of chelates, cross-linking agents, detoxification drugs, foods or functional materials by using the alpha-methyl-D-mannoside as a ligand or a cross-linking agent.