144results about How to "Improve sweeping efficiency" patented technology

The invention relates to a nanoparticle-added composite foam system used for an oil and gas field and a preparation method thereof. The composite foam system comprises components of, by mass, 0.3 to 0.5 parts of an anionic surfactant, 1 to 1.5 parts of modified silica nanoparticles, 0.03 to 2.3 parts of counter-ion salt, and 100 parts of water. The method comprises mixing the abovementioned components according to ratio, stirring by using a magnetic stirrer, standing, and then rapidly stirring to form well stable foam using a Waring Blender way. According to the composite foam system, the produced foam has a longer half life than that of foam stabilized by ordinary surfactant, and a larger start-foaming volume than that generated by adding a foam stabilizer The system has advantages of simple formula and preparation technology and good salt tolerance and temperature tolerance, can adapt to complex oil reservoir condition underground, does not pollute stratum, is capable of effectively blocking large channels and improving sweeping efficiency, and thus has good application prospects in oil field exploitation, especially in foam displacement.

The invention provides an artificial foaming-oil huff and puff oil production method for a heavy oil reservoir. The method comprises the following steps: filling aqueous solution of foaming oil accelerant and nitrogen into the heavy oil reservoir, wherein the foaming oil accelerant comprises a foaming oil accelerant A, a foaming oil accelerant B and a foaming oil accelerant C of which the mass ratio is 1:1:1; soaking for 1 to 5 days; opening a well to produce oil in a certain production differential pressure range and stopping producing oil when the single-well daily oil production reaches single-well economic limit; repeating the step 1 to the step 3 and stopping production until the single-well cyclic oil production reaches cyclic economic limit, wherein the heavy oil reservoir has a reservoir thickness of over 2m, reservoir permeability of over 10*10<-3> mu<m2>, a reservoir temperature of lower than 120 DEG C, viscosity of crude oil of over 50mPas, oil saturation of over 30 percent and water saturation of over 50 percent. According to the artificial foaming-oil huff and puff oil production method for the heavy oil reservoir, which is provided by the invention, the viscosity of crude oil can be reduced and elastic energy of fluid can be increased so as to increase single-well productivity and a recovery ratio of an oil field.

The invention discloses an air foam slug flow driving process for the oil recovery of an oil field, comprising the following steps of: 1 determining type and proportion of the used foam liquid, slug volume ratio and on-site injection manner of the used air and the foam liquid during the air foam slug flow driving by an indoor test; and 2 carrying out the air foam liquid slug flow driving on site,wherein the oil flow driving process comprises the following steps of: preparation before the oil flow driving; slugging a pad fluid; slugging the air foam; alternatively injecting the air and foam liquid slug from a specially manufactured device to a target well for many times; and continuously carrying out the oil flow driving on the target well by a water or air injection method according to the dynamic change condition of the target well and a conventional oil displacement method after the injection of the air foam slug is finished. The invention has the advantages of reasonable design, simple and convenient construction steps, good use effect and convenience of realizing, can effectively solve various practical problems of poor water injection effect, difficult improvement on the water injection capability, poor oil flow driving efficiency and the like during the ultralow reservoir waterflooding.

The invention discloses a submicron polymer active microsphere profile-control oil-displacement agent which is an active polyacrylamide gel with a molecular weight of 1-8 million, and the agent is prepared through a dispersion-polymerization synthesizing method, wherein a novel transportable oil displacement agent is obtained.

The invention discloses an optical device spectrum response measurement method based on double sideband modulation and stimulated Brillouin scattering effect, comprising steps of dividing an optical carrier wave which is outputted by a light source into two paths, performing frequency-beating in a photoelectric detector by a scanning frequency double sideband signal and a carrier having the frequency shifted after the signal passes through the optical device to be detected, obtaining two radio frequency signals which have two different frequencies and carry spectral response information of the optical device to be detected at the scanning frequency double sideband signal frequency position, using a radio frequency amplitude phase extraction module to respectively extract amplitude phase information of two radio frequency signals to obtain an amplitude-frequency response and a phase frequency response of the optical device to be detected at the optical detection signal frequency, changing the wavelength of the optical detection signal and repeating the above process to obtain the spectral vector response information of the optical device to be detected. The invention also discloses an optical device spectrum response measurement device based on the double sideband modulation. Compared with the prior art, the optical device spectrum response measurement method and measurement device greatly improve the measurement range and the measurement efficiency.

The present invention provides an eluent for repairing contaminated soil. The eluent comprises, by weight, 50-70 parts of a nonionic biosurfactant and 5-30 parts of an anionic surfactant. The compounding synergism of the nonionic biosurfactant and the anionic surfactant enhances the solubilizing effect of the eluent on organic pollutants in soil, especially polycyclic aromatic hydrocarbons, so theelution efficiency of the eluent is significantly improved; and the components of the elutent are biodegradable, so the eluent does not cause secondary damage to the environment in the use process, and is an efficient, clean and environmentally-friendly in situ eluent for repairing contaminated soil. The eluent provided by the invention is firstly foamed in the use process, so the spreading efficiency of an eluent solution in the soil medium is increased, the migration of the eluent in the horizontal direction is enhanced, and the uniformity and the repairing efficiency of the eluent in the soil are further improved.

The invention relates to the field of foam flooding and discloses a foamer and a foam gas flooding method. The foamer comprises a weak-cationic amphoteric surfactant, water and at least one of cationic surfactant, amphoteric surfactant and alcohol. The foam gas flooding method comprises the steps of injecting the weak-cationic amphoteric surfactant containing foamer and gas into an oil reservoir, and carrying out foam profile control and oil displacement. According to the foamer and the method, disclosed by the invention, the foamer has high foamability, stability and profile control and oil displacement capability, so that the corrosion action on injection equipment and an oilfield injection-production system caused by air foam in an air foam flooding profile control and oil displacement process can be obviously lowered; and the foamer not only can be applied to a foam profile control and oil displacement process of ordinary strata, but also can be applicable to the foam profile control and oil displacement process under the condition that stratum water is high in degree of mineralization and high in calcium and magnesium ion content.

The invention provides a method for increasing the oil recovery rate through a self-generation carbon dioxide system after polymer flooding. The method for increasing the oil recovery rate through the self-generation carbon dioxide system after polymer flooding comprises the step that the self-generation carbon dioxide system and spacer fluid are injected into an oil well after polymer flooding. The self-generation carbon dioxide system and the spacer fluid are alternately injected into the oil well multiple times. According to the method for increasing the oil recovery rate through the self-generation carbon dioxide system after polymer flooding, various yield increasing principles are combined, and various technical problems are effectively solved; (1) decompression and injection augmenting effects are achieved, specifically, alkaline blockage relieving and acid blockage relieving of zones near a water injection well are achieved by injecting chemical solutions into the water well, and thus the decompression and injection augmenting effects are achieved; and (2) a heat releasing effect is achieved, so that the viscosity of crude oil is decreased, and the oil displacement efficiency is improved.

The invention discloses a foam flushing technology for polychlorinated biphenyls (PCBs) polluted soil. The technology comprises the following steps of: manufacturing ectopic foam by using surfactant and nitrogen, controlling the property of the foam by controlling the gas-liquid ratio and the particle diameter of the foam, and performing foam flushing in a pressed injection mode by using the foam, wherein the gas-liquid ratio of the foam is 100:35-100:0.2, the particle diameter is 10 to 3,500 microns, and the injection pressure is 0.1 to 15 meters water columns. Compared with the conventional foam flushing technology, the technology has the advantages of improving the wave and the efficiency of a flushing fluid in a soil medium by controlling the property of the foam and finally improving the removal efficiency of the PCBs.

The invention discloses a viscoelastic weak gel profile control agent which is applied in oil field and oil well water injection operation. The viscoelastic weak gel profile control agent comprises the following components in parts by weight: 0.15-0.25 part of viscoelastic surface activity polymer, 0.05-0.15 part of cross-linking agent, 0.001-0.005 part of conditioning agent, and 99.8-99.6 parts of water. The viscoelastic surface activity polymer comprises the following components in parts by weight: 20-30 parts of acrylic amide, 1-2 parts of 3,3-dimethylacrylic acid, 1.5-3.5 parts of 2-acrylamido-2-dodecyl ethanesulfonic acid and/or 1-4 parts of N,N-dimethyl-allyl-hexadecyl ammonium chloride, 60-75 parts of deionized water and 0.3-1 part of initiating agent. The initiating agent comprises the following components in parts by weight: 2.5-3.5 parts of ammonium persulphate and 1 part of sodium sulfite. The viscoelastic weak gel profile control agent of the invention has a certain gel strength, capacity for lowering oil-water surface tensility and adjustable gel forming time, can improve water injection profile, lower oil-water surface tensility, wash away residual oil in a pore canal and improve water injection recovery ratio.

The invention discloses a conveyor belt type sweeper for a flat ground. The sweeper comprises a rechargeable battery, a sweeping roller support, a sweeping roller motor, a sweeping roller and transmission rollers. A universal wheel stand and a fixed wheel stand are arranged under a base, land wheels are installed on the universal wheel stand and the fixed wheel stand respectively, and a handle is arranged on the right side of the base; a supporting plate is arranged on the handle, an electronic control switch is installed on the supporting plate, a garbage can is arranged at the left side of the handle, and conveyer belt upper supports are arranged at the two sides of the garbage can respectively; chain wheels are installed at the ends of the transmission rollers and on conveyer belt power motors respectively, the chain wheels are connected through a chain, and a conveyer belt is installed on the transmission rollers; a partition board is arranged on the conveyer belt, and a tool box is arranged at the left side of each conveyer belt upper support. By the adoption of the sweeper, sweeping efficiency can be improved, structure is simple, investment cost is low, maintenance is convenient, operation is easy, the ground can be well cleaned, and labor intensity can be relieved.

The invention provides a process of deep profile control over a low-permeability oil reservoir. The process comprises the steps that firstly, an RD movable jelly profile control agent is injected into an oil layer; secondly, retarding swelling soft particles are carried by the RD movable jelly profile control agent in a suspended mode and injected into the oil layer; thirdly, a composite particle profile control agent is injected into the oil layer so as to block a high-permeability channel; fourthly, an RD movable jelly profile control agent is injected into the oil layer again to push the particles to the deep so as to perform deep profile control. The RD movable jelly profile control agent comprises, by mass, 0.05%-0.25% of amphoteric ionic polymer, 0.05%-0.25% of cross-linking agent A, 0.05%-0.25% of gel promoting agent B and the balance of water. The composite particle profile control agent comprises, by mass, 0.2%-2% of retarding swelling soft particles, 0.05%-0.25% of amphoteric ionic polymer, 0.1%-0.5% of cork particles and the balance of water. By means of the process, the gelling performance and gelling strength of a profile control system under the low-permeability oil reservoir condition can be improved, so that deep profile control over the low-permeability oil reservoir is achieved, and the crude oil recovery ratio is increased.

The invention discloses a gel breaking liquid based modifying and flooding agent, which mainly comprises the following raw materials in percentage by weight: 0.1-0.4% of thickened water/clean fracturing fluid/gel breaking liquid, 0.004%-0.01% of a co-surfactant, and the balance of oilfield injected water. The preparation method of the modifying and flooding agent comprises the following steps: preparing thickened water/clean fracturing fluid/gel breaking liquid, and adding a co-surfactant and oilfield injected water into the gel breaking liquid, so that the modifying and flooding agent is obtained. The prepared modifying and flooding agent can be directly injected into a water injection well, and then enters an oil well through the water injection well, so that the oil-water interfacial tension can be effectively reduced; an oleophyllic rock surface is converted into a weak hydrophilic surface, so that the capillary force is reduced; and remaining oil is activated, so that the oil recovery is greatly enhanced.

The invention provides a method for improving the recovery ratio of a sensitive heavy oil reservoir. The method utilizes combined application of a high-temperature clay stabilizer, a sustained-release acidizing fluid system, an efficient oil-displacing agent and carbon dioxide in the development of the sensitive heavy oil reservoir to improve the single-well development effect and the recovery ratio of the sensitive heavy oil reservoir. The technical scheme is that the method comprises the steps of first utilizing the temperature-sensitive sustained-release acidizing fluid system to treat a polluted treat near-well-bore zone, then injecting the liquid carbon dioxide, utilizing the high-temperature clay stabilizer to protect an oil layer before steam injection and injecting a high-temperature oil-displacing agent system while the steam injection; then performing well shut-in for soaking and well opening for gushing and putting a pump into a well to perform continuous oil extraction. A field test shows that the oil-steam ratio of an average period of a vertical well reaches to 0.4, the oil-steam ratio of an average period of a horizontal well reaches to 0.6, and the periodic oil yield exceeds 1000t. A laboratory test shows that the final recovery ratio can reach to higher than 35% by adopting a process related to the method for improving the recovery ratio of the sensitive heavy oil reservoir.

The invention provides an exploitation method and device for a low-pressure compact oil reservoir. The method comprises the following steps: arranging a horizontal well row according to a distributionsituation of geological pressure of an area where an oil reservoir to be exploited is located, wherein the horizontal well row comprises a huff and puff well and an oil exploitation well, and the huff and puff well and the oil exploitation well are arranged in a spacing manner; performing volume fracturing reservoir reconstruction on the huff and puff well and the oil exploitation well; and performing water injection and seepage oil exploitation by using the huff and puff well, and displacing the oil exploitation well adjacent to the huff and puff well by using a displacement effect between the wells so as to realize displacement oil exploitation. By use of the embodiments in the invention, the advantages of a seepage oil exploitation technology are exerted; meanwhile, exploitation of low-seepage or ultralow-seepage oil reservoirs is accelerated to the maximum extent by using the displacement between the wells, and the overall exploitation degree and the recovery rate of the low-pressure compact oil reservoir are increased.

The invention provides an authigenic heat injection composition for underground catalytic oxidation of crude oil. The injection composition is a three-phase stable disperse system composed of water phase (anionic surfactant), an auxiliary agent, solid phase (nano-catalyst) and gas phase (air); the injection composition comprises the following raw materials: 0.1-1% of anionic surfactant taken as water phase, 0.1-1% of auxiliary agent, 0.1-1% of nano-catalyst taken as solid phase, and the balance of water, wherein the sum of the mass percent of the water phase, the auxiliary agent, the solid phase and the water is 100%; the volume ratio of the adding amount of the air to the total amount of the water phase, the auxiliary agent, the solid phase and the water is (3-7): 1. After the injection composition is adopted, the sweep efficiency of the air can be improved, the synchronous carrying of the catalyst and the air can be realized, and the problem of separation of underground air and catalyst can be avoided; the composition contains the efficient nanometer oxide catalyst, and the crude oil can be catalyzed to have oxidation reaction under the mild conditions, and therefore the problem that the stratum is blocked by coking caused by severe oxidation reaction is effectively avoided.

The invention discloses a selective plugging agent for a horizontal well and a preparation method thereof, which belong to the technical field of oil field chemistry. The plugging agent comprises the following components in part by weight: 6.50 to 7.50 parts of polymer monomer, 4.50 to 5.75 parts of surface active intermediate, 0.85 to 1.00 part of modifier, 85.75 to 88.15 parts of water. The method comprises the following steps of: adding the surface active intermediate into water, adding the polymer monomer and uniformly stirring; making the surface active intermediate react with the polymer monomer, adding the modifier and stirring to react; and drying a reaction product, grinding the dry product into particles, and screening to obtain selective plugging agent particles for the horizontal well. The plugging agent provided by the invention has the advantages of high oil and water selectivity, convenience in synthesizing and producing, stable chemical properties, high adaptability and simple construction technology; simultaneously, the sweep efficiency of the development of a high-water-cut old oilfield horizontal well is improved, the swept volume is expanded, and the petroleum recovery ratio is increased.

The invention discloses a frequency sweeping method of a user terminal and a frequency sweeping device of the user terminal. The frequency sweeping method of the user terminal comprises the following steps that: when historical valid frequency points in all frequency bands to be searched are invalid frequency points, valid frequency points are searched in each frequency band to be searched sequentially according to preset search priority; and one valid frequency point in valid frequency points of a frequency band to be searched in which a first valid frequency point is searched is selected as a current valid frequency point. Compared with the prior art, the frequency sweeping method and device of the user terminal provided by the invention can shorten the frequency sweeping time of the user terminal and the frequency sweeping efficiency of the user terminal.

The invention discloses a frequency sweeping method and device for a small bandwidth communication system. A to-be-swept band is divided into a plurality of subbands according to system performance; frequency points in each subband are determined according to the minimum bandwidth of a system; FFT operation, slide accumulation operation and grid deviation accumulation operation are carried out ontime domain signals according to fixed gain; and after power distribution of all frequency points on the to-be-swept band are obtained, whether to adjust gain values to recalculate the power of each frequency point is decided according to a threshold demand. All frequency points of which power satisfying the threshold demand are screened according to the method, namely, all resident frequency points are obtained. According to the method and the device, the collected time domain signals are processed according to the fixed gain; the AGC (Automatic Gain Compensative) convergence time does not need to be reserved; and the integrated data processing time is greatly reduced. According to the method and the device, the frequency point distribution in each subband is determined according to the minimum bandwidth of the system and the power of each real frequency point is directly calculated in an bandwidth mode, so the sweeping omission condition resulting from the fact that calculated central frequency points are not the real frequency points is avoided.

The invention provides a displacement exploitation method for heavy oil reservoir after artificial foam primer and steam flooding. The method comprises: selecting a target oil reservoir and a target well group; stopping a well group steam injection and oil exploitation process, and injecting an artificial foam oil primer slug and a gas slug into injection wells; opening wells to exploit oil when formation pressure rises so that bottom-hole static pressure of a production well reaches a set value; after injecting the gas slug, continuing the inject steam to the injection wells, judging whether injection transfer conditions and lower economic limit are satisfied or not, and determining whether to continue oil exploitation or stop oil exploitation. By using an artificial foam oil primer in the method, it is possible to reduce crude oil viscosity and surface tension for a near-wellbore formation, gas is dispersed in micro bubble form in oil-in-water emulsion, rheological properties of crude oil are improved, oil-gas-water to-be-mixed phase fluid is formed, elasticity energy is supplemented to the formation, overall mobility of fluid in the oil reservoir is improved, mobility of crude oil is improved, and single-well productivity and final recovery are increased.

The invention discloses a small-sized belt type sweeper car, comprising a clutch of the main body part, a special conveyor belt and a trash collecting box. A sweeping part comprises a front sweeping head and rear sweeping wheels; a convey and transmission part comprises a front sweeping head, a rear sweeping wheel transmission device and a transmission device of the special conveyor belt which are connected with the clutch by each transmission part. The sweeper car not only backwards sweeps the trash to an arc plate according to needs but also forwards sweeps the trash to the arc plate on a rear sweeping wheel box after the structure is changed simply and throws out the trash backwards; the special conveyor belt conveys the trash to the trash collecting box, thereby being different from other types of sweeper cars that dedusters are used in. When encountering large block trashes such as beverage bottles, the small-sized belt type sweeper car is not easy to block and is applicable to the trash sweeping operation in a narrow place.

The invention provides an injecting method of an underground modifying and viscosity-reducing nano catalyst for thickened oil. The method is characterized in that the precursor micro-emulsion of the modifying and viscosity-reducing nano catalyst for the thickened oil is injected into a stratum first, the precursor micro-emulsion is water-in-oil type micro-emulsion, the precursor micro-emulsion can automatically enter oil phase and evenly dispersed after being injected into the stratum due to the fact that the the outer phase of the micro-emulsion is oleophylic hydrogen donor, nano reaction occurs when the temperature of inner phase rises to 160-200 DEG C, and no extra energy needs to be injected due to the fact that the decomposition temperature is lower than the modifying temperature of the thickened oil. Compared with a method directly injecting the nano catalyst, the injecting method has the advantages that the automatic oil finding function of the nano catalyst can be achieved, the problem that nano catalyst is easy in absorption and blocking during injection can be avoided, effective injecting of the nano catalyst is achieved, and the modification and viscosity reduction of crude oil can be effectively catalyzed under a medium-temperature condition.

The invention relates to a ground control time-sharing separated layer water injection method for oil fields as well as cable control water distribution devices and an application method thereof. Theground control time-sharing separated layer water injection method comprises the following steps: in a ground process of water injection wells, a flow control device is installed and connected with aground control box, a layered packer separates water injection layers, the cable control water distribution devices corresponding to the water injection layers are installed in an underground water injection tube pillar, and corresponding cable control water distribution device of each water injection layer in the underground water injection string is collected with the ground control box througha control cable; the ground control box controls the injected water volume and injection time of each water injection layer on the ground in real time, and the cable control water distribution deviceof each water injection layer underground finishes the injection allocation water volume and injection allocation time of the corresponding water injection layer under the coordination of the flow control device according to programs and instructions set by the ground control box. The ground control time-sharing separated layer water injection method is not limited by the number of the water injection layers, repeated opening and closing can be realized, the control is accurate, and the intelligent degree is high.