38results about How to "EOR effect" patented technology

The invention discloses a method for improving the carbon dioxide displacement yield by using surfactants. The method comprises the following steps of: uniformly mixing selected surfactants and supercritical carbon dioxide according to a mass ratio being (0.00061:1) to (0.00338:1) under the conditions of the pressure being 8MPa and the temperature being 50 DEG C to be used as displacement agents; and injecting the displacement agents into an oil reservoir. The method has the advantages that the surfactants capable of reducing the minimum miscibility pressure of carbon dioxide and crude oil can be preferably selected; and when the surfactants are added in the injected carbon dioxide for carbon dioxide displacement operation, the carbon dioxide displacement yield can be improved.

The invention relates to an oil-displacing agent and an oil-displacing method for enhancing the recovery ratio of high-temperature, high-salinity and high-hardness reservoir crude oil. The oil-displacing agent is composed of the following components in percentage by mass: A, 0.05-0.07% of an amine oxide type amphoteric surfactant; B, 0.15-0.20% of alkylphenol ethoxylate carboxylate; and C, the balance of water. The oil-displacing method disclosed by the invention is implemented through injecting the oil-displacing agent into a natural core subjected to oil-displacing under the conditions that the oil reservoir temperature is 100-120 DEG C, the total salinity of formation water is (10-15)*10<4> mg/L, and the amount of calcium-magnesium divalent metal ions is 7000-10000 mg/L, so that residual oil is in contact with the oil-displacing agent, and then the residual oil is fully displaced. The oil-displacing agent provided by the invention reaches the magnitude order of 10<-3> mN/m under the condition of high-temperature, high-salinity and high-hardness salt reservoirs, and the interfacial tension still can be maintained in an ultra-low interfacial tension state after the oil-displacing agent is aged for a long time under the condition of oil reservoirs, therefore, the oil-displacing agent is applied to the tertiary oil recovery production of oil fields.

The invention discloses an experimental device for simulating substrate-crack static/dynamic imbibition and oil discharge and method of the experimental device. The experimental device for simulatingsubstrate-crack static/dynamic imbibition and oil discharge comprises a high-pressure gas cylinder, an injection pump, an intermediate container, a core holder and a back pressure pump, wherein the lower end of the intermediate container is connected with the injection pump, and the upper end of the intermediate container is connected with the high-pressure gas cylinder; a compact core is arrangedat the inner bottom of the core holder; a fracturing proppant compaction belt is arranged at the upper end of the compact core; a left through hole and a right through hole are separately formed in the position, located on the end surfaces of the cylinder wall of the core holder, of the left end surface and right end surface of the fracturing proppant compaction belt; and a first through hole andthe left through hole are both connected with the upper end of the intermediate container, a second through hole and the right through hole are both connected with the right end of the back pressurepump, and an oil-gas separation and metering device is arranged at the upper end of the back pressure pump. The experimental device for simulating substrate-crack static/dynamic imbibition and oil discharge is used for studying the phenomenon of imbibition and diffusion of injected fluid from cracks to dense substrate under the condition of high temperature and high pressure, and the law of mass transfer between substrate-crack in the fractured dense oil reservoir is determined through the device and the experimental method, and reference is provided for enhancing oil recovery in the dense oilreservoir.

The invention discloses a blocking system and a blocking method for channeling inhibition in carbon dioxide non-miscible flooding of a low permeability reservoir. The system is mainly prepared from the following raw materials in percentage by weight: 1%-2% of fine mineral particles, 0.2%-0.3% of polymer, 0.01%-0.02% of compound crosslinking agent, 0.04%-0.1% of retarder, 0.01% of deoxidant, 0.1%-0.5% of surfactant and the balance of water. By virtue of monitoring the steam injection pressure of a wellhead in real time and adjusting the system, graded control of high-pressure steam injection, 'gas channeling' and 'escape channeling' processes in the carbon dioxide non-miscible flooding is realized and the development effect of the carbon dioxide non-miscible flooding of the low permeability reservoir is improved.

The invention relates to a heavy oil displacement method using a wedged vicious slug. The method includes the steps of 1, dividing a nonhomogeneous reservoir into a plurality of layers according to water absorbing capacities, and acquiring permeability Ki of each reservoir; 2, designing three slugs, namely a pre-slug, a main wedged slug and a trailed slug, according to the permeabilities Ki and the physical properties in heavy oil and reservoirs; 3, alternately injecting the heavy oil reservoir with the pre-slug which is prepared with low-concentration B III-type poly-surfactant and which enters a high permeability layer to emulsify crude oil; 4, injecting the reservoirs with the main wedged slug for multiple rounds; and 5, injecting the trailed slug with low-concentration B III-type poly-surfactant or fresh water generally. In each round, the main wedged slug is divided into three small slugs; the small slugs in each round are combined by regulating the corresponding concentrations by the B III-type poly-surfactant according to formation permeability. According to the method, the nonhomogeneous heavy oil reservoirs are emulsified to reduce viscosity, the wedged equivalent vicious slug is used for equi-fluidity displacement, and swept volume is increased; accordingly, recovery efficiency of heavy oil can be further increased, investment can be reduced and operation can be simplified.

The invention relates to a petroleum sulfonate anionic surfactant and a preparation method thereof. The method comprises the following steps: mixing a crude oil fraction and a solvent phase, and carrying out sulfonation reaction at -20-30 DEG C by using liquid sulfur trioxide or fuming sulfuric acid as a sulfonating agent; aging the sulfonated product, and carrying out neutralization reaction until the reaction product becomes neutral or slightly alkaline; and separating the product of the neutralization reaction to obtain the petroleum sulfonate anionic surfactant. The invention also provides a petroleum sulfonate anionic surfactant prepared by the method. The preparation method has the characteristics of simple preparation technique, low investment cost and the like. The petroleum sulfonate anionic surfactant prepared by the method has higher adaptability and oil displacement efficiency than other chemical oil displacement agents.

The invention discloses carboxylic acid higher alcohol ester-trimethyl ammonium chloride and application thereof in a clay stabilizer. The carboxylic acid higher alcohol ester-trimethyl ammonium chloride has double functions of oil displacement and swelling prevention, is particularly suitable for a low-permeability and water-sensitive crude oil reservoir, and consists of the following main components in percentage by mass: 10 to 30 percent of carboxylic acid higher alcohol ester-trimethyl ammonium chloride, 1 to 20 percent of trimethylamine hydrochloride and 50 to 90 percent of water. The carboxylic acid higher alcohol ester-trimethyl ammonium chloride is realized by the technical scheme of: adding an excessive trimethylamine aqueous solution and alpha-chlorinated fatty acid into a pressure reaction kettle; under the condition of the stirring, controlling the reaction temperature to between 50 and 100 DEG C, the reaction pressure to be between 1 and 0.2 MPa, and the reaction time to be between 3 and 5 hours; after the reaction is finished, reducing the temperature to between 40 and 50 DEG C; dripping 30 percent hydrochloric acid into a reaction solution so as to control the pH value of the reaction solution to between 6 and 8; and then diluting the reaction solution to certain concentration by using clear water to obtain an oil displacing type surfactant used for preventing swelling.

The invention discloses a nano material which is prepared by carrying out polymerization reaction on a mixture containing coupled montmorillonite, an organic hydrophobic monomer, an organic hydrophilic monomer and an initiator. The nano material used in a low-permeability oil field is provided, after the nano material and a surfactant generate a synergistic effect, a gain effect is reflected, and a nano-oil displacement agent is obtained. The nano material has the advantages of good long-term stability, low interfacial tension and recovery efficiency improvement.

The invention discloses a gas injection oil well selecting method. The gas injection oil well selecting method comprises the step of selecting oil well gas injection effect influence factors, wherein the gas injection influence factors comprise construction positions, reservoir body types, well storage relations, remaining oil types, reserve sizes and water cut rising rules; and the step of conduction gas injection potential estimation on all oil wells in a working section sequentially according to the construction positions, the reservoir body types, the well storage relations, the remaining oil types, the reserve sizes and the water cut rising rules, and therefore the oil well to be subjected to gas injection primarily is selected. By means of the gas injection oil well selecting method, the oil well with gas injection potential can be rapidly selected, the gas injection periodic average oil increment is increased by years, up to now, the gas injection periodic average oil increment is greatly improved, and the gas injection effective rate can reach 96.1%. As a whole, by means of the gas injection oil well selecting method, ultra-deep layer fracture-cavity type oil deposit gas injection is greatly improved, the oil recovery effect is improved, and therefore the production benefits are greatly improved.

The invention discloses a viscous-elastic particle oil-displacing agent with a fluorescence characteristic and a preparation method therefor. The oil-displacing agent is a terpolymer composed of three structural units: acrylamide, N-vinyl carbazole and 2-(dimethylamino)ethyl methacrylate. The preparation method is as follows: 100 parts of acrylamide is dissolved in 250-290 parts of water to prepare a solution, 0.3-0.5 part of 2-(dimethylamino)ethyl methacrylate is dissolved in 40-60 parts of water to prepare a solution, 0.0004-0.025 part of N-vinyl carbazole is dissolved in 0.2-4 parts of ethanol to prepare a solution, the solutions are added in a three-necked bottle in order, and the three-necked bottle is placed in water-bath at a temperature of 15-25 DEG C; after nitrogen input is carried out for 20min, a solution prepared after 0.015-0.035 part of potassium peroxodisulfate is dissolved in 20-40 parts of water is added into the three-necked bottle; when the temperature rise of the reaction solution is more than 1 DEG C, nitrogen input is stopped, after the reaction is finished, the three-necked bottle is placed in a water bath kettle, thermal insulation is carried out for 3-5h, then gel is taken out, cut into pieces, dried, crushed and screened, and a powdery product can be obtained.

The invention relates to a method for extracting oil by utilizing indigenous microbes of an oil pool subjected to polymer flooding. In the method, a method activating the indigenous microbes of the oil pool is adopted, and an activating agent comprises diammonium phosphate, sodium nitrate, molasses or cane sugar, compound amino acid, ammonium molybdate, copper sulfate, ferric chloride and zinc sulfate; and plugging can be further carried out on a deep channel and a roaring channel of the oil pool by injecting controlled-release nutritional agents and inorganic gel slugs. The method for extracting oil by utilizing the indigenous microbes of the oil pool subjected to the polymer flooding has obvious extraction rate enhancement effect, relatively low-cost used raw material and ground and underground dual environmental protection without increasing the difficulty of the post processing of produced fluids.

The invention discloses a method for performing thick oil huff-puff cold recovery by using bio-nano materials. The method comprises the following steps of: respectively preparing bio-nano slug liquids by using different bio-nano materials to form combined slugs, wherein the combined slugs are at least two of BioNanoEM bio-nano materials of A series, F series, L series and J series, and respectively stirring or stirring after diluting with water to form different bio-nano slug liquids; and during oil displacement treatment, sequentially injecting the different bio-nano slug liquids into an oil-containing porous medium according to the sequence, promoting seepage of an oil phase in pores, then performing water-phase oil displacement, pushing the bio-nano slug liquids to go deep into the oil-containing porous medium, expanding the sweep range of the bio-nano slug liquids, enabling the oil phase to flow out of the porous medium along with bio-nano emulsion for extraction and recovery, and realizing oil phase yield increase and recovery efficiency improvement. The method disclosed by the invention has the advantages of high efficiency, energy conservation, simple construction process, convenience in industrial application and the like, can improve the yield of a thick oil reservoir and has broad application prospects in the field of oil exploitation.

The invention discloses a method for measuring flow controlling particle density under simulated real reservoir conditions. The method comprises the following steps: step 1: determining the mass M1 ofthe simulated container; step 2: introducing a reservoir simulation liquid into the measuring system until no bubbles appear, and determining the total mass M2 of the simulation unit; step 3: calculating the mass M3 of the simulated container filled with the reservoir simulation liquid; step 4: drying the flow controlling particles to be treated and determining the mass M4 after drying; step 5: adding the dried treated flow controlling particles to the simulated container, and heating and pressing the simulated container to a preset temperature value and a preset pressure value, and then measuring the total mass M5 of the simulation unit in this state; step 6: calculating the density value of the flow controlling particles under simulated real reservoir conditions based on the measured masses of M1, M2, M3, M4 and M5. The measurement method can be measured under the real conditions of a simulated high temperature and high pressure reservoir, and the density of the particles under reservoir conditions can be tested.

The invention relates to a low-temperature high-salt-resistant deep profile control and displacement crosslinking system as well as a preparation method thereof. The crosslinking system comprises the following components in percentage by mass: 0.1-0.7% of a polymeric flocculant, 0.1-0.8% of hexamethylenetetramine, 0.01-0.2% of resorcinol, and 0.05-1.0% of micromolecular organic acid, with the balance being water. The cross-linking system can be suitable for deep profile control and flooding of low-temperature (20-40 DEG C) high-salinity (the degree of mineralization is larger than 6.0*10<5> mg/L) oil reservoirs, the gelling time is controllable in 36-96 h, the freezing strength E-H level is adjustable. The preparation method is simple and practical, non-flowing high-strength gel can be formed at the low temperature, and the cross-linking system is good in stability and high in plugging strength under the high-salinity condition, effective plugging can be formed on a high-permeability stratum or a dominant channel, and the effect of improving the recovery ratio is remarkable.