Yangtze University

Huan Yang

Xiaorong Yu

Gaoshen Su

PeiYue Wu

Kailu Wang

Wei Wang

ZhaoFei Ma

XueMin Yan

ZhongFu Cheng

Fei Deng

Hao Li

Lei Zhang

Yang Li

Weichu Yu

Ying Zhang

Wenming Shu

Aibin Wu

Hui Zhao

Fei Ding

Dongkui Zhou

Wenjie Xia

Pingtian Fan

Zhuyang Jiang

Qiang Li

Chang Xiao

Wenchuan Wu

Jianglu Jing

Jieqiong Cheng

Chunyuan Wu

Zhengdong Lei

Zhixue Huang

Chaoyi She

Shuaishuai Li

Zhenhu Lv

Beibei Zhang

A combined catalytic viscosity reducing system includes a catalyst slug, a heat generating system slug, a gas injection slug, and a water-soluble viscosity reducing system slug. The catalyst slug includes 10%-15% of azacarbene iron, 15%-30% of tert-butyl hydroperoxide, 2%-5% of phosphoric acid, 2%-5% of hydrogen donor, and 0.5%-1% of emulsifier agent, and the others are solvent. The heat generating system slug includes 10%-30% of NaNO%-25% of NHCl, and 3%-10% of acid initiator, and the others are water, totaling 100%. The water-soluble viscosity reducing system slug, according to mass percentage, includes 0.2%-0.5% of surfactant and 2%-10% of alkali, and the others are water. The combined catalytic viscosity reducing system can effectively reduce viscosity without injecting steam, and the viscosity reduction rate can reach 96.5%.

Combined catalytic viscosity reducing system and a use of the combined system

Disclosed are a double-response self-degradable temporary plugging agent and a preparation method thereof. The double-response self-degradable temporary plugging agent is prepared by compounding a crosslinkable monomer with a temperature-sensitive degradability and an inorganic material with an acid solubility with a first monomer, a dispersant, an initiator and water, and subjecting the resulting mixture to a polymerization.

Double-response self-degradable temporary plugging agent and preparation method thereof

A pH-sensitive temporary plugging agent and its preparation method, and the use thereof in exploitation of a low-permeability oil reservoir are disclosed. The temporary plugging agent is prepared by raw materials including, in percentages by mass, 3-8% of carboxymethyl chitosan, 0.2-0.7% of gelatin, 0.1-0.6% of an initiator, 5-15% of a toughener, and a balance of water, wherein the initiator is a solution of AgNOin ammonia water having a concentration of 0.1-0.3 mol/L, and the toughener is a carboxyl-terminated hyperbranched polyester.

pH-sensitive temporary plugging agent, preparation method thereof, and use thereof in exploitation of low-permeability oil reservoir

Disclosed is catalyst composition, a process for preparing the catalyst composition, and a use of the catalyst composition. The catalyst composition comprises 1 wt % to 4 wt % of free azacarbene, 1 wt % to 2 wt % of azacarbene iron, 15 wt % to 30 wt % of a phase transfer catalyst, 1 wt % to 5 wt % of a hydrogen donor, 5 wt % to 10 wt % of phosphoric acid, 0.5 wt % to 1 wt % of emulsifier, with the rest being solvent. This disclosure also provides a process for preparing the catalyst composition, comprising: mixing the free azacarbene and the azacarbene iron with the solvent according to a ratio, then adding and mixing the phase transfer catalyst and the hydrogen donor, then adding and mixing the phosphoric acid and the emulsifier to obtain the catalyst composition. The beneficial effect of this disclosure is: only less azacarbene iron and free azacarbene are needed to achieve rapid and efficient viscosity reduction of heavy oil.

Catalyst composition, a process for preparing the catalyst composition, and a use of the catalyst composition

The present disclosure relates to a profile control and oil displacement agent for an oil reservoir and a preparation method thereof. The profile control and oil displacement agent is prepared by uniformly dispersing polymer microspheres, an activator and a solvent. The polymer microspheres are micron-sized dry-powdered microspheres, which are prepared by stirring and polymerizing a first monomer, a second monomer, an initiator, a hydrophobic nano-powder and water in a specific proportion. The profile control and oil displacement agent of the present disclosure can reduce the oil-water interfacial tension, has good long-term stability, simple preparation and low cost, avoids solvent waste, and can be applied to the deep profile control and oil displacement system of oil fields.

Profile control and oil displacement agent for oil reservoir and preparation method thereof

The present disclosure provides a temperature-responsive self-degradable temporary plugging agent and a preparation method thereof as well as its application in plugging the wellbore, which relates to the technical field of oilfield exploitation. The temporary plugging agent provided in the present disclosure includes preparation raw materials of the following mass percentages: monomer 4-6%, crosslinker 0.2-1%, initiator 0.02-0.06%, degradation catalyst 0.05-0.1%, chain transfer agent 0.01-0.05%, and the balance water. The temporary plugging agent of the present disclosure is liquid before gelling, with a low viscosity and a good fluidity, and easy to be pumped. When being pumped into the wellbore, the temporary plugging agent may crosslink at the temperature of the reservoir section, with good gelling properties. At the end of the operations, it can be degraded by itself, without drilling tools, with no need for gel breaking, and with no need for additional degradation promoters.

Temperature-responsive self-degradable temporary plugging agent and preparation method thereof as well as its application in plugging the wellbore

An enhanced oil recovery method includes: screening out implementation well that meet the requirements of a preset standard; selecting the target interval that can be used for enhanced oil recovery in the implementation well; obtaining the reservoir parameters and perforation parameters of the target interval, so as to divide the target interval into several groups of swallowing and exhaling segments, injecting the infection liquid containing and simmer the well for a period of time; and after the well simmering, the oil-water mixture replaced by the injection fluid is produced from each exhaling segment.

Enhanced oil recovery method with single well huff and puff and inter-segment oil displacement after horizontal well fracturing

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Jingzhou, China

Huan Yang