Southwest Petroleum University

Tianfu Yongxing Laboratory

Tianjin University of Science and Technology

Wanfen Pu

Rui Liu

Daijun Du

Lin Sun

Jinzhou Zhao

Fayang Jin

Shishi Pang

Rui Jiang

Zijia Liao

Xing Zhao

Chao Shen

Zezhou Fang

Ying Xiong

Jintao Li

Yongming Li

Yijian Chen

Xiao Guo

Kun Wang

Quantang Fang

Yubin Yang

Xiang Li

Bo Zhou

Bing Wei

Wei Liao

Pengfei Chen

Shuai Zhao

Yan Shi

Jianyong Xie

Yanjie Chu

Huancai Fan

Binyang Zou

Bowen Chen

Ye Ju

Kexing Li

Shuyu Song

Yangyang Zhang

Yangbing Wen

Mian Wang

Qingyuan Chen

Xiaodong Tang

Peiwen Xiao

Shi Gao

Ziyuan Yi

Su Liu

Desheng Qian

Wenlian Xiao

Tao Wu

Yuanyuan Wang

Mingming Song

Jitian Ren

Yingxue Xu

Shuaishuai Liu

Shengen Chen

Lingli Zheng

The present invention discloses a POSS-based hybrid supercritical COthickener and a preparation method thereof, and relates to the technical field of oil and gas field development. The preparation method of the thickener comprises the following steps: reacting tetramethyl tetravinylcyclotetrasiloxane, trimethylolpropane trimethacrylate, perfluoroacrylate and POSS containing one double bond in a molar ratio of 1-5:1-2:1-2:0.005-0.01 under the action of a catalyst to obtain the thickener. The preparation method of the POSS-based hybrid supercritical COthickener of the present invention is a bulk reaction, does not require the addition of a solvent, and does not pollute the human body and the environment in the production process. The POSS-based hybrid supercritical COthickener of the present invention has a high thickening efficiency on supercritical carbon dioxide and can better increase the viscosity of the supercritical carbon dioxide, so that the carrying and supporting effects of the supercritical carbon dioxide are improved.

POSS-based hybrid supercritical COthickener and preparation method thereof

The present invention discloses a supercritical CO2 thickener for shale gas reservoir based on hollow mesoporous silica nanoparticles and a preparation method thereof, and relates to the technical field of oil and gas field development. The preparation method of the thickener includes: reacting a monomer consisting of fluoroacrylate, styrene and vinyl acetate in a molar ratio of 3-5:1-2:1-2 with 2%-5% of a total weight of hollow mesoporous silica nanoparticles with carbon-carbon double bonds under the action of an initiator to obtain the thickener. The preparation method of the present invention does not involve the addition of organic solvents during the reaction process and thus does not cause harm to the human body. The thickener of the present invention has good CO2 viscosity-increasing effect and good sand carrying performance, and can effectively improve the fracturing effect.

Supercritical CO2 thickener for shale gas reservoir based on hollow mesoporous silica nanoparticles and preparation method thereof

A displacement system designed for robust heterogeneous oil reservoirs and its application within the oil exploitation field. System comprises a polymer-enhanced foam plugging agent and an active polymer flooding agent. Plugging agent consists of 0.12% bio-polysaccharide polymer diutan gum foam stabilizer and 0.4% α-olefin sulfonate foaming agent by mass. The active polymer flooding agent is formulated through free radical polymerization, with components comprising a total monomer concentration of 27.5%, wherein monomer A to monomer B ratio is 7.5:2.5, monomer C constitutes 5.5% of the total monomer concentration, and water comprises the remaining. Monomer A is acrylamide, monomer B is 2-acrylamide-2-methyl propane sulfonic acid, and monomer C is a quaternary ammonium salt type active monomer. Demonstrated through parallel core displacement experiments, this displacement system exhibits effective displacement in heterogeneous oil reservoirs with a permeability gradation of 30 at 65° C., significantly enhancing oil recovery rates in robust heterogeneous oil reservoirs.

Displacement system suitable for strong heterogeneous oil reservoir and its application

The present invention discloses a CO2 responsive core-shell multi-stage swelling microsphere and a preparation method thereof. The preparation method comprises the following steps: adding a styrene monomer into a sodium dodecyl sulfate solution for emulsion polymerization to obtain a spherical polystyrene solution, taking azobisisobutyronitrile and ethylene glycol for Pinner reaction to obtain an azo compound with hydroxyl functional groups at two ends, taking the azo compound with the hydroxyl functional groups at two ends as a raw material for Schotten-Baumann reaction with methacryloyl chloride to obtain BPAB, adding the BPAB into the spherical polystyrene solution to prepare an active polystyrene core solution, and dissolving the active polystyrene core solution, acrylamide, a CO2 responsive monomer, a CO2 responsive cross-linking agent and a stable cross-linking agent into water to obtain a target product. The CO2 responsive core-shell multi-stage swelling microsphere of the present invention can remarkably improve the CO2 flooding sweep efficiency.

CO2 responsive core-shell multi-stage swelling microsphere and preparation method thereof

A tight oil reservoir COflooding multi-scale channeling control system and a preparation method, including nanoscale COresponsive worm-like micellar systems and micron-scale COresponsive dispersion gel, are provided. The nanoscale COresponsive worm-like micelle system is prepared by COreactive monomers and organic anti-ion monomers stirred in water. The micron-scale COresponsive dispersion gel is made of acrylamide, a responsive monomer, a silane coupling agent modified hydroxylated multi-walled carbon nanotubes as raw materials, cross-linked in water. The tight oil reservoir COmulti-scale channel control system, has strong flow control ability during COdisplacement, and high-strength carbon nanotubes are introduced into the micro-scale COresponsive dispersion gel, which effectively improves the strength and long-term stability of the dispersion gel, significantly enhances the sealing effect on cracks, and after displacement of the COof the system, the worm-like micelles revert to spherical micelles with good responsive reversibility.

Tight oil reservoir COflooding multi-scale channeling control system and preparation method

The present disclosure discloses methods for preparing an in-situ nano emulsifier. The preparation method may include obtaining a solution by dissolving hydrated ferric chloride (or ferric chloride) and hydrated ferrous sulfate (or ferrous sulfate) into deionized water at a first temperature; obtaining an ethanol solution dissolved with an oil-soluble surfactant by dissolving an oil-soluble surfactant into ethanol at a second temperature; and adding a certain volume of ammonia water and the ethanol solution dissolved with the oil-soluble surfactant in the solution to obtain an in-situ nano emulsifier. The in-situ nano emulsifier may be applied to development of the oil reservoir through an application process. The application process may include preparing a nano emulsifier solution and a surfactant solution; sequentially injecting the surfactant solution and the nano emulsifier solution into a formation; and injecting a spacer liquid slug into the formation for replacement.

Methods for preparing and applying a nano emulsifier

The present invention discloses a method for enhancing the recovery factor of heavy oil by in-situ oil-water emulsion with high phase inversion point, and the method is aimed at the development of heavy oil reservoir by water injection under the condition that the performance parameters of crude oil emulsion meet the following three specific requirements: (A) The viscosity of the crude oil is less than 6,000 mPa&#xb7;s; (B) At the reservoir temperature, the phase inversion point of the crude oil emulsion is greater than or equal to 70%, and the emulsion viscosity corresponding to the phase inversion point is 2-6 times of the crude oil viscosity; (C) At the reservoir temperature, when the water cut is less than or equal to the phase inversion point, the flow rate ratio of crude oil emulsion to crude oil is 0.2 to 0.9.

Method for enhancing the recovery factor of heavy oil by in-situ oil-water emulsion with high phase inversion point

The present invention discloses an in-situ emulsification and viscosity increase system with a high phase change point. The system consists of the following components in percentage by weight: 0.2&#x2dc;0.5% of water-soluble surfactant, 0.2&#x2dc;1.5% of oil-soluble surfactant, 0.02&#x2dc;0.5% of lipophilic colloidal particles, 0.02&#x2dc;0.2% of carrying agent and the balance of mineralized water. The water-soluble surfactant is one of or a combination of petroleum sulfonate, cocamidopropyl betaine, fatty alcohol ether sulfonate, alkanolamide and alkyl glycoside; the oil-soluble surfactant is one of or a combination of propylene glycol monostearate, fatty glyceride, polyoxyethylene sorbitan monostearate, polyoxyethylene fatty alcohol ether, oleic diethanolamide, dodecylamine, octadecyl primary amine, sodium oleate and petroleum acid; the lipophilic colloidal particles are one of liquid paraffin, graphite powder and polyhedral oligomeric silsesquioxane; the carrying agent is one of carboxymethyl-&#x3b2;-cyclodextrin, chitosan quaternary ammonium salt, chitosan hydrochloride, xanthan gum and guar gum. The system is used for water-flooding oil reservoirs and can significantly improve the development effect of water-flooding heavy oil reservoirs.

In-situ emulsification and viscosity increase system with high phase change point and application thereof in water-flooding oil reservoir

A high-temperature and high-pressure microscopic visual flowing device and an experimental method are provided by the present disclosure, comprising a seepage simulation system, a micro-displacement and metering system connected to the seepage simulation system, and an image acquisition and analysis system; the seepage simulation system consists of a visual high-temperature and high-pressure kettle, a microscopic core model placed in the visual high-temperature and high-pressure kettle, and glass carriers arranged above and below the microscopic core model; the glass carriers are provided with sealing rubber sleeves, and the visual high-temperature and high-pressure kettle is provided with an annular heating jacket; an outlet of the microscopic core model is provided with a microflow channel which is connected to the micro-displacement and metering system through a pipe, effectively reducing the metering error caused by the dead volume of the pipe.

High-temperature and high-pressure microscopic visual flowing device and experimental method

A lignocellulose nanofibril material, a stable foam system based thereon, a preparation method and an application thereof are provided. The lignocellulosic nanofibril material includes the following components: 0.5-20 wt % of wood flour, 0.1-10 wt % of (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl, 2-25 mmol/g of an oxidant, 6-15 wt % of NaBr, and the remaining is water. The stable foam system based on the lignocellulosic nanofibril material includes: 0.1-1.0 wt % of the lignocellulosic nanofibril material, 0.2-1.0 wt % of a surfactant, 0.1-10 wt % of sodium chloride, 0.1-1.0 wt % of calcium chloride, 0.1-1.0 wt % of magnesium chloride, 0.1-1.0 wt % of sodium sulfate, and a balance of water.

Lignocellulose nanofibril material, stable foam system based thereon, preparation method and application thereof

An amphoteric two-dimensional nanosheet and a preparation method thereof are provided. The amphoteric two-dimensional nanosheet is prepared by the following steps: uniformly dispersing few-layered graphene oxide into toluene and then adding alkylamine coupling agent to a mixture of the few-layered graphite oxide and the toluene for reaction; amine terminated graphite oxide dispersion that has been prepared is fully dispersed in toluene-dimethylformamide mixed solvent, and then, alkyl glycidyl ether is added into the above solution for reaction, so as to obtain the amphoteric two-dimensional nanosheet. The amphoteric two-dimensional nanosheet of the present disclosure can be prepared by modifying two-dimensional graphite oxide, to spontaneously form water-in-oil Pickering emulsion at an oil-water interface, compared with emulsion of conventional surfactants, the present disclosure can effectively stabilize the waterflooding front, improve the sweep volume of waterflooding, have a simple synthesis process for convenient large-scale production, and be widely used in waterflooding development reservoirs.

Preparation method of amphoteric two-dimensional nanosheet

An in-situ emulsification and viscosity increase system with controllable viscosity consists of the following components in percentage by weight: 0.3&#x2dc;1.5% of emulsifier, 0.05&#x2dc;0.5% of ultrafine colloidal particles, 0.01&#x2dc;0.1% of suspending agent and the balance of mineralized water. The emulsifier is one of or a combination of petroleum sulfonate, petroleum carboxylate, sodium dodecyl sulfate, sodium dodecyl benzenesulfonate, alkyl glycoside, aliphatic alcohol ether carboxylate, aliphatic alcohol ether sulfonate, hydroxysulfobetaine and alkanolamide. The ultrafine colloidal particles are one of ultrafine silicon dioxide, ultrafine montmorillonoid, ultrafine ferric oxide, ultrafine ferroferric oxide, ultrafine aluminum oxide and ultrafine titanium dioxide. The suspending agent is one of partially hydrolyzed polyacrylamide, amylose, carboxymethyl chitosan, hydroxymethyl cellulose, xanthan gum and sodium alginate. The system is applicable to a water-flooding oil reservoir with the viscosity of lower than 50 mPa&#xb7;s, has a very broad coverage scope and outstanding economic benefits and can effectively promote efficient development of water-flooding oil reservoirs.

Insatiability emulsification and viscosity system with controlled viscosity and its application in water-driven reservoir

Polymer-monodispersed nano-microspheres for deep profile control and flooding. The polymer-monodispersed nano-microspheres comprise (% wt.): 0.05 to 2.5% of macromolecules A, 0.05 to 2.5% of macromolecules B, 0.002 to 0.05% of an oxygen scavenger, and mineralized water. Macromolecules A comprise a straight-chain water-soluble polymer with an ethyl ether or propyl ether structure. Macromolecules B comprise a water-soluble polymer with a hydroxyl or polyphenolic structure. Macromolecules A and macromolecules B are intermolecularly assembled under the drive of extremely strong hydrogen bonds in aqueous solutions to rapidly construct monodispersed nano-microsphere dispersion glue with a controllable size. The monodispersed nano-microspheres have a good seepage in a porous medium and excellent deep profile control and flooding capabilities.

Polymer-monodispersed nano-microspheres for deep profile control and flooding, and preparation method thereof

A mine application method for in-situ nano-microspheres is provided. A water-soluble macromolecule A base fluid, a certain amount of isolation fluid (an isolation fluid slug can be designed according to actual conditions of the mine), and a water-soluble macromolecule B base fluid are pumped into the formulation in sequence; when macromolecules A and B are mixed or contacted with each other, they are assembled under the drive of an extremely strong hydrogen bonding effect and quickly constructed in-situ to form a nano-microscale spherical dispersion. The nano-microspheres have a certain fluidity control ability and excellent fluid flow diversion performance, which significantly improves a fluid absorption profile of the heterogeneous formation, exhibits deep intelligent profile control and flooding, and greatly increases the crude oil recovery rate.

Mine application method for in-situ nano-microspheres to increase crude oil recovery rate

A particulate profile control agent self-adaptive to a size of formation pore throat and a preparation method thereof include: raw materials and mass fraction for preparing a system including a main agent of 0.04&#x2dc;0.2%, a nucleating agent of 0.005&#x2dc;0.01%, a crosslinking agent of 0.002&#x2dc;0.04%, an additive of 0.005&#x2dc;0.01% and water. The preparation method includes: adding the main agent in proportion to the water and evenly mixing the mixture of the main agent and the water, and then adding the additive, the crosslinking agent and the nucleating agent in turn so as to form the profile control agent; pumping the profile control agent into the formation to be reacted at a reservoir temperature for a period of time to form colloidal particles on the spot for sealing off a high-permeability layer. The present disclosure is of easy operation and low cost, low initial viscosity and good injectivity.

Particulate profile control agent self-adaptive to size of formation pore throat and preparation method thereof

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Chengdu, China

Wanfen Pu