Yangtze University

Petrochina Company Limited

Jingzhou Modern Petroleum Technology Development Co. Ltd

Weichu Yu

Ying Zhang

Wenming Shu

Aibin Wu

Dongkui Zhou

Shanwen Yu

Fei Ding

Lei Zhang

Hui Zhao

Pingtian Fan

Wenjie Xia

Xiangsong Xiao

Huan Yang

Jingfeng Dong

Zhichen Wang

Chaoyi She

Shuaishuai Li

Zhenhu Lv

Jizhao Xing

Fengjuan Zhang

Baocheng Wu

Yaolu Li

Qingwen Zeng

Yumin Li

Lei Yu

Jianglu Jing

Yongtao Song

Zhenhu Lyu

Rui Li

Zhengdong Lei

Disclosed is a device for evaluating damage of fracturing fluid to reservoir and operation method thereof, the device includes a liquid storage tank, a suction tube, a chromatography device, a bracket, a receiving container and a height adjuster; the disclosure has the following beneficial effects: since different liquids pass through the porous medium at different time and speed and the silica gel particles will not expand when immersed in the liquid, a porous structure is formed by placing silica gel particles of different sizes to simulate the pore-throat structure of unconventional oil and gas reservoirs, hence removing the influence of fracturing fluid on the hydration and expansion damage of the reservoir matrix, by testing the time and flow rate of different fracturing fluids flowing through the silica gel pores, the degree of damage caused by fracturing fluids to unconventional oil and gas reservoirs is evaluated.

Device for evaluating damage of fracturing fluid to reservoir and operation method thereof

A main chain of a temperature-resistant and anti-collapse multi-branched polymer fluid loss reducer is composed of the following repeating unit (I): In the repeating unit (I): x:y:z=(20&#x2dc;80):(20&#x2dc;80):(2&#x2dc;30); the Rand Rgroups are alkylamines having a multi-branched structure. The beneficial effect of the multi-branched polymer fluid loss reducer is: introducing cheap acrylamide branch monomer into the polymer monomer system of acrylamide and 2-acrylamido-2-methylpropanesulfonic acid, the preparation process is simple, the reaction conditions are mild, and the production cost is significantly reduced.

Temperature-resistant and anti-collapse multi-branched polymer fluid loss reducer and preparation method thereof

The invention discloses a carboxymethyl inulin graft polymer scale and corrosion inhibitor and a preparation method thereof. The main chain of the carboxymethyl inulin graft polymer scale and corrosion inhibitor consists of the following repeating unit (I): in the repeating unit (I), x:y=(20&#x2dc;80):(20&#x2dc;80); the range of z is from 2 to 70, the degree of carboxymethyl substitution is from 1.5 to 2.5. The beneficial effect of the technical scheme proposed in the present invention is: it has excellent scale inhibition and corrosion inhibition properties; the monomers are cheap and easily available; the reaction conditions are mild and easy to control; at the same time, the monomer raw materials don't contain phosphorus and nitrogen, and are environmentally friendly.

Carboxymethyl inulin graft polymer scale and corrosion inhibitor and preparation method thereof

Disclosed is a method for determining three-dimensional in-situ stress based on displacement measurement of borehole wall, including the following steps: pumping the prefluid and the sand-carrying fluid into the target interval, and injecting the biological oil displacement agent into the target interval in sequence; pumping temporary plugging agent into the target layer to implement crack plugging diverting; pumping the sand-carrying liquid into the target interval, and injecting the biological oil displacement agent into the target interval. The beneficial effect of the technical scheme proposed in this disclosure is: by injecting oil displacement agent to fracturing fluid, the temporary plugging diverting fracturing is integrated constructed with enhanced oil recovery, at the same time, it can overcome the incomplete removal of temporary plugging agent and the water lock effect of fracturing fluid caused by diverting fracturing.

Volumetric fracturing method of temporarily plugging and diverting through functional slick water with oil displacement agent injected simultaneously

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

The invention discloses a three-dimensional cage-like hyperbranched monomer and preparation method and application thereof. The three-dimensional cage-like hyperbranched monomer has the structural formula I: wherein in the structural formula I: X is any one of &#x2014;O, &#x2014;S, &#x2014;NH; y is any integer from 2 to 8; R is &#x2014;H or &#x2014;CH. The beneficial effect of the technical scheme proposed in the present invention is: by introducing easily polymerizable olefin groups, the carboxyl group and amide group are combined in the three-dimensional cage-like hyperbranched monomer to make the water solubility good, and it can be copolymerized with many other monomers to obtain the three-dimensional cage-like hyperbranched polymer; when used as an additive for wellbore working fluids, due to the hyperbranched structure of the polymer, it has good salt and temperature resistance, and also has viscosity increasing, filtration loss, and flocculation properties; meanwhile, the synthesis method is simple and the cost is low.

Three-dimensional cage-like hyperbranched monomer, and preparation method and application thereof

Disclosed is slick water volumetric fracturing method with large liquid volume, high flow rate, large preflush and low sand ratio, including the following steps: (a) evaluating the reservoir parameters; (b) determining the perforation position and a perforation parameters of a fracturing interval; (c) determining the fracturing parameters; (d) performing a perforation operation on the fracturing interval; (e) injecting acidizing fluids into the perforation; (f) alternately injecting preflush and sand-laden fluids into the fracturing interval several times; (g) injecting displacement fluids into the fracturing interval; wherein the flow rate is not less than 12 m/min. The beneficial effect of the technical scheme proposed in the present invention is: by using a low viscosity slick water fracturing fluid with high flow rate, the pressure of the fracturing fluid is increased, thereby increasing the stimulated reservoir volume and increasing the fracturing yield.

Slick water volumetric fracturing method with large liquid volume, high flow rate, large preflush and low sand ratio

Disclosed is an integrated construction method of fracturing and tertiary oil recovery for low-permeability reservoir, including the following steps: dividing the target layer into several fracturing intervals; determining the amount of fracturing fluid required for the target fracturing interval; determining the flow rate of the target fracturing interval; determining the pumping construction procedure for the target fracturing interval; perforating the target fracturing interval; injecting oil displacement fracturing fluid into the target fracturing interval for fracturing construction; wherein the oil displacement fracturing fluid is a fracturing fluid to which an oil displacement agent is added. The beneficial effect of the technical scheme proposed in this disclosure is: by adding an oil displacing agent to the fracturing fluid, the fracturing and tertiary oil recovery are integrated, thereby improving the effect of fracturing and tertiary oil recovery, while also avoiding the water lock effect of the reservoir. Compared with the existing 'first fracturing then tertiary oil recovery' scheme, it has obvious advantages.

Integrated construction method of fracturing and tertiary oil recovery for low-permeability reservoir

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Jingzhou, China

Weichu Yu