39results about How to "Good temperature resistance and shear resistance" patented technology

The invention relates to a fracturing fluid capable of resisting high salinity water quality. The fracturing fluid is characterized by being composed of a base fluid and a cross-linking fluid which are fully mixed in proportion. The base fluid contains a chelate cosolvent and a chelate stabilizer, wherein the chelate cosolvent can restrain high salinity of water quality and promote swelling of guanidine gum. The base fluid comprises 98.2-98.65 parts of high salinity surface water, 0.1-0.15 part of the chelate cosolvent,0.3-0.4 part of thickener, 0.1-0.15 part of bactericide, 0.3-0.5 part of clay stabilizer, 0.5 part of demulsifying cleanup agent and 0.05-0.1 part of the chelate stabilizer; the cross-linking fluid comprises 50 parts of water, 50 parts of organic cross-linking agents and 0.35 part of gel breaker; and the fracturing fluid comprises 99.2-99.5 parts of the base fluid and 0.5-0.8 part of the cross-linking fluid. By aid of the fracturing fluid, water resources can be saved effectively, and the success rate for fracturing construction can be improved.

The invention relates to a carboxymethyl hydroxypropyl guanidine gum fracturing fluid which is used for fracturing reformation of a high-temperature and low-permeability reservoir. The carboxymethyl hydroxypropyl guanidine gum fracturing fluid comprises the components by weight percent: 0.25-0.6% of carboxymethyl hydroxypropyl guanidine gum, 0.2-0.6% of cross-linking agent, 0.2-0.4% of cross-linking regulator, 0.5-1% of clay stabilizer, 0.05-0.1% of bactericidal preservative, 0.2-0.5% of discharge aiding agent, 0.0001-0.15% of ammonium persulfate and the balance of water. A preparation method of the fracturing fluid comprises the steps of: adding clear water into a large tank, adding the carboxymethyl hydroxypropyl guanidine gum into the large tank under the stirring condition, and then sequentially adding the clay stabilizer, the discharge aiding agent, the cross-linking regulator and the bactericidal preservative into the large tank; and stirring for 10 minutes until the concentration or the viscosity of liquid at the upper part and the lower part of the large tank is uniform and consistent. During fracturing construction, the cross-linking agent and gel breaker are added into the large tank according to the requirement. The carboxymethyl hydroxypropyl guanidine gum fracturing fluid has the effects of being suitable for the reservoir temperature of 80-200DEG C, reducing the residue of the fracturing fluid and the construction friction, and meeting the demand of fracturing reformation of the high-temperature and low-permeability reservoir.

The invention relates to a high-concentration water-in-oil emulsion-state associating polymer fracturing fluid and a preparation method thereof. The fracturing fluid comprises the following components in mass fraction: 38.7-45.18% of water, 25.30-28.67% of diesel oil, 25-30% of a fracturing fluid thickening agent and 2.53-2.88% of an emulsifier. The high-concentration water-in-oil emulsion-state associating polymer fracturing fluid disclosed by the invention has a stable time greater than 15 days at 0 DEG C-40 DEG C and has the characteristics that the fracturing fluid is easy to prepare, dissolve and disperse and the like, and rapid mixing, construction and fracturing on the spot can be achieved.

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 super a guanidine gum fracturing fluid, which is used for the fracturing modification of a high-temperature and low-permeability water-sensitive storage layer. The super guanidine gum fracturing fluid comprises the following components in percentage by weight: 0.25-0.6% of super guanidine gum, 0.5-2% of potassium chloride, 0.5-1.0% of organic clay stabilizing agent, 0.05-0.1% of JA-1 sterilizing preservative, 0.2-0.5% of non-ionic discharge aiding agent, 0.1-0.2% of crosslinking regulator, 0.0001-0.15% of ammonium persulfate, 0.2-0.6% of organic boron and zirconium compound crosslinking agent and the balance of water. The super guanidine gum is added into clear water ,followed by circulating for 15 minutes at a big displacement; and then, the potassium chloride, the organic clay stabilizing agent, the discharge aiding agent, sodium thiosulfate, triethanolamine, the crosslinking regulator and sterilizing preservative are successively added to cause the concentration or the viscosity of liquid to be consistent. During the fracturing construction, the crosslinking agent and the ammonium persulfate are added. The super guanidine gum fracturing fluid has the effects that a super guanidine gum fracturing fluid series formula suitable for the temperature of the reservoir stratum is formed, the residues of the fracturing fluid are reduced, and the modification requirement on the high-temperature and low-permeability water-sensitive storage layer can be satisfied.

At present, more than 90 percent of fracturing fluids used in the fracturing improvement of oil and gas fields are water-based fracturing fluids with water as dispersion medium, and as a result, for gas reservoirs with low formation pressure, low permeability and strong water-locking characteristic, particularly highly water-sensitive gas reservoirs, the difficulty of fluid flowback can be easily caused because the formation pressure coefficient is greatly smaller than the pressure coefficient of water in a shaft; and formation pores can be easily blocked due to the water-locking effect of formations to cause the failure of fracturing improvement. Because low-molecular weight alcohol, particularly methanol, has a lot of excellent physical and chemical properties, the low-molecular weight alcohol can be used in the improvement of low-pressure, water-sensitive formations for stimulation, and compared with conventional water-based fracturing fluids, methanol-based fracturing fluid has the characteristics of low surface tension, good water-solubility, low freezing point, high steam, high compatibility with formation rocks and the like. The invention relates to a thickening agent for methanol-based fracturing fluid, which is used in the fracturing stimulation process of natural gas wells or oil wells; because methanol and water can be formed into any proportions of mixtures, the methanol-based fracturing fluid can absorb the water constrained by water-locking formations to the maximum limit after entering the formations, and moreover, as the fracturing fluid is drained out of the ground, the water locking of the formations is released, which is favorable for the flowback of the fluid.

The invention belongs to the technical field of petrochemical engineering, and particularly relates to an anhydrous fracturing fluid suitable for shale gas and a preparation method of the anhydrous fracturing fluid. The anhydrous fracturing fluid suitable for shale gas is prepared from the following raw materials in percentage by mass: 0.5-2% of a crosslinking agent, 2-6% of a complex iron activator and the balance of a low carbon hydrocarbon; in a pressure vessel with a pressure of 0.8-3.0 MPa, the crosslinking agent is added into the low carbon hydrocarbon to be uniformly mixed, the complex iron activator is added to be stirred for 2-5 min, so that the anhydrous fracturing fluid suitable for shale gas is obtained; and the low carbon hydrocarbon is one or a mixture of more of propane, butane, n-hexane, n-heptane and kerosene. The anhydrous fracturing fluid suitable for shale gas easily flows back, has a good sand-carrying property, does not harm reservoirs, and can satisfy the needs of fracturing reconstruction of shale oil and gas and strong water-sensitive compact oil and gas reservoirs. A synthetic method is simple, and the content of an effective component dialkyl phosphate in a product is high, thereby facilitating the industrialization production of the anhydrous fracturing fluid.

The invention discloses a high density fracturing fluid and further provides a method for preparing the fracturing fluid. To solve the technical problem, the following technical scheme is adopted, wherein a formula of the high density fracturing fluid comprises, by weight, 0.4-0.5% of a thickening agent, 25-47% of a weighting agent, 0.2-0.4% of a multi-effect additive, 0.4-0.6% of a cleanup additive, 0.4-0.6% of a cross-linking agent, 0.001-0.1% of a gel breaker, and the balance of water.

The invention discloses an oil-gas field fracturing fluid, a temporary plugging agent and a well cementing agent containing a PVA (Polyvinyl alcohol) fiber. The PVA fiber is prepared by spinning PVA being 1000 to 3500 in polymerization degree, and 80 to 99.9 mole percent in alcoholysis degree. The oil-gas field fracturing fluid has the advantages of higher temperature resistance and shearing resistance, small environmental damage, low cost, environmental friendliness, very good sand carrying function and facilitation of fracturing fluid flowback; the oil-gas field well cementing agent can enhance the strength and the toughness of a well cementing material, can play a role in preventing leakage, is degradable and has low environmental damage; the oil-gas field fracturing temporary plugging agent has a good filtration reduction effect, forms a shielding layer at a position to be plugged temporarily to realize successful steering of the fracturing fluid, and is degradable; components left underground do not cause environmental pollution.

The invention belongs to the field of oil field production, and specifically relates to a high temperature resistant crosslinked acid system for acid fracturing and a preparation method thereof. An improved high temperature resistant crosslinked acid thickener is adopted, the temperature resistance and stability of an acid solution are improved, a corresponding additive with good compatibility andthe crosslinked system with controllable delay, temperature resistance and shear resistance are adopted, and good rheological performance and corrosion inhibition performance at the temperature of 160 DEG C are realized. Compared with the prior art, the high temperature resistant crosslinked acid thickener adopted in the invention has the advantages of high dissolving speed, complete dissolutionin hydrochloric acid with the mass fraction of 15-31% for 20 min and stable performance in the acid solution within 10 days; through the added concentrations of a high-temperature corrosion inhibitorand a corrosion inhibition synergist, the corrosion inhibition performance at different temperatures is adjusted; and by adjusting the concentration of the crosslinked agent, different delay, temperature resistance and shear resistance performances can be realized, so that deep acid fracturing transformation of an oil-gas reservoir is realized.

The invention belongs to the field of oil field production enhancement, and particularly relates to an adsorption slow-release acid system for acid fracturing. The adsorption slow-release acid systemfor acid fracturing comprises the following raw material composition in percent by mass: 0.3%-1.0% of a slow-release acid thickener, 5.0%-60.0% of an adsorbent, 0.5%-1.5% of a synergist, 1.0%-5.0% ofa corrosion inhibitor, 0.5%-1.0% of an iron ion stabilizer, and the balance hydrochloric acid of 15-28%. A multi-component copolymerized polymer is used as the thickener of a slow-release acid, and the thickener and the synergist can produce viscoelastic effects, so that the slow-release acid has relatively good rheological properties at a high temperature. According to reservoir geological characteristics, construction displacement and the like, a sand addition ratio of the adsorbent is adjusted, and adjustment of a total amount of the slow-release acid is realized while sand blockage is effectively prevented. The system not only makes full use of performance advantages of an existing acid solution system, but also originally uses the solid adsorbent to transport a high-concentration acidsolution to the front of an acid-fracturing fracture, and at the same time, the adsorbent can also play multiple functions such as temporary blocking and direction changing.

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.