Table of Content

10 June 2021, Volume 43 Issue 3

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GEOLOGY EXPLORATION

Pore-infillings in Stratiform Siliceous Rocks of the Dengying Formation in Wangcang Area, Northern Sichuan Basin

LIU Xiaohong, SHI Zhangjun, FENG Mingyou, WANG Liangjun, WANG Xingzhi

2021, 43(3):  1-11.  DOI: 10.11885/j.issn.16745086.2019.09.03.01

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Dissolution pores within stratiform siliceous rocks of the Sinian Dengying Formation in Wangcang Area (Northern Sichuan) are filled with multistage minerals. Petrological and geochemical analyses are conducted to reveal the filling sequence of minerals and elucidate the process of fluid interaction. The results show that dolomite, aphanitic-fibrous chalcedony, fine-mesocrystalline quartz and coarse-megacrystalline quartz are typical fillings in the dissolution pores of siliceous rocks, corresponding to six episodic fluid events. After formation of early siliceous rocks, semi-filling saddle dolomite was formed by the dissolution-filling superposition of magnesium-rich hydrothermal fluid derived from deep basin in the first stage. Sparry calcite was formed during the second stage by replacement of siliceous hydrothermal fluid. In the third stage, asphalt was formed in the Silurian to Devonian. Hereafter, the microcrystalline quartz and fibrous chalcedony were formed by hydrothermal solution in closed system during the fourth stage. The fine-mesocrystalline quartz and coarse-megacrystalline quartz were precipitated in the fifth stage and sixth stage, respectively. The fine-mesocrystalline quartz was formed by siliceous fluids during the Carboniferous to Permian, and the coarse-megacrystalline quartz was formed by weak-saturated silica aqueous precipitation along fracture or near-equilibrium conditions in the pores during the Triassic. The superimposition of magnesium-rich hydrothermal fluids and siliceous hydrothermal processes in deep basins can improve stratiform siliceous rocks, and some siliceous rocks with dolomite moldic pores and fractures are suspective special reservoirs.

Reservoir Characteristics and Comprehensive Evaluation of the Middle Jurassic Shaximiao Formation in Middle of Western Sichuan Depression

ZHANG Ling, CHEN Gongyang, YE Sujuan, YANG Yingtao, CHENG Leli

2021, 43(3):  12-24.  DOI: 10.11885/j.issn.16745086.2019.08.28.03

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The Shaximiao Formation of Middle Jurassic in the West Sichuan Depression is a delta-shore-shallow lake sedimentary system developed under the background of multiple provenance. Different provenance background has great influence on reservoir and the exploration effect is obviously different the reservoir characteristics of the near-source and distal-source depositional systems have been analyzed and compared on the basis of core and drilling cutting analysis, thin section observation and reservoir test analysis. The results imply that the near-source reservoir is dominated by low-maturity, coarse grained sandstone. Its favorable reservoirs consist of fine-grained sandstone characterized by matured lithology, low calcite cement, and well-developed fractures. The preservation of porosity is the major controlling factor of reservoir quality. On the contrary, the favorable reservoirs of distal-source depositional system are composed of low-maturity, medium-grained sandstone with low calcite cement and high feldspar contents. Pressure dissolution has significantly contributed to the development of secondary porosity, which further improve the quality of reservoirs. On such basis, classification standards are established to evaluate the reservoirs quality of the two depositional systems. The results show that the reservoir development of distal-source depositional system is significantly better than the near-source system, since its favorable reservoir has greater lateral extent.

Architecture Characterization and Fluid Migration Mechanism of Composite Point Dam in Meandering River

WANG Dacheng, LIU Yikun, BAI Junhui, FU Qingchun, CHEN Fen

2021, 43(3):  25-36.  DOI: 10.11885/j.issn.16745086.2020.05.18.02

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Based on the abundant data resources and the advantage of inter-well distance under the condition of high density well pattern, the characterization of the sand body architecture, remaining oil analysis and fluid migration mechanism of a meandering river point dam in a sedimentary unit in a block in Changyuan Daqing were studied. Aiming at the problem of multi-solutions of quantitative identification of point dam architecture elements, the parameter correction of the calculated results was carried out through the internal morphological difference of the meandering river single sand body, so as to realize the deterministic quantitative characterization of configuration elements. At the same time, the modeling idea of using structure to represent the shape of sand body is proposed, and the 3D characterization of point bar sand body internal configuration is realized by directional grid editing technology. Finally, through the numerical simulation technology to analyze the distribution of remaining oil and fluid migration, to clarify the mechanism of fluid migration under the influence of configuration, and put forward the next direction of tapping potential.

Hydrocarbon Accumulation Conditions of Baikouquan Formation of Triassic in Cheguai Slope Area

YU Jingwei, SUN Bo, YU Haitao, GAO Zijie, REN Chufan

2021, 43(3):  37-50.  DOI: 10.11885/j.issn.16745086.2019.09.16.03

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The fuzzy recognition on hydrocarbon accumulation conditions in Baikouquan Formation of Cheguai slope area is a problem, which has been hindering deeper oil and gas exploration. Hydrocarbon source rock, reservoir, cap rock, migration conditions and trap types were investigated with drilling, seismic, well test and laboratory data. The study results show that many hydrocarbon source rocks supply hydrocarbon for Baikouquan oil reservoir, Fengcheng Formation and lower Wuerhe Formation being the major source rocks. Sandstone reservoirs of distributary channels (underwater) with good physical properties match well with mud-stone cap rocks developed in the three member of Baikouquan Formation, all of which made favorable reservoir-seal assemblage. Faults, hyper-osmotic sands, ancient landform and abnormal pressure create conditions for oil and gas migration and control migration path. There were two trap types named structural-litho-trap in high position and litho-trap in slope and low position. Congruent with ancient landform, sedimentary face, planar graph of faults and pressure coefficient, the result shows there are three favorable reservoir zones in study area which can supply exploration direction in Baikouquan Formation, and II reservoir zone has the best exploration potential.

Technology Research of Igneous Reservoir Exploration in Dabasong Uplift

LI Zonghao, WANG Chunli, LI Hui, CHEN Jing, WANG Zhongquan

2021, 43(3):  51-60.  DOI: 10.11885/j.issn.16745086.2019.10.04.01

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The volcanic rocks is development of the lower assemblage in Junggar Basin. Due to some objective factors influence such as deep burial depth, active and lasts long structural movement, many problems exits in the identification and interpretation of the complex faults system and deep volcanic rock body. Therefore, identification of faults using some approaches such as structure oriented filtering, eigenstructure combine with body curvature provide by GeoEast interpretation sub-system platform. Base on drilling data and 3D seismic, defining seismic reflection characteristics of differern volcanic lithology, established recognition model of volcanic facies in the study area. According to the multi-attribute pattern recognition and waveform clustering analysis provided by GeoEast, the lithology distribution of deep volcanic rock can be quickly and efficiently predicted, and favorable exploration targets in deep volcanic rocks are determined and optimized. Makes clear the volcanic target is development of the new layer series in the study area, which is an important exploration area to find large-scale oil and gas reservoirs.

Multilevel Quantitative Evaluation of 3D Geological Model of Complex Fault Block Reservoir

ZHANG Qinglong, LIU Lei, JIA Zhiwei, LIU Zhongliang

2021, 43(3):  61-70.  DOI: 10.11885/j.issn.16745086.2019.11.21.01

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In order to evaluate quantitatively and to raise the quality of 3D geological model, after clarifying the research purposes and geological characteristics of the study area, by selecting several key indicators, and the analytic hierarchy process is used to get the accurate weight. What is more, according to the development stage of the research area and the quality of geological data, reasonable standards are established, the actual score of each index is obtained by comparing actual model with score criterion, and the shortcomings of the model are by the low items. And the overall quality of three-dimensional geological model is evaluated quantitatively by accumlating actual scores of various indicators. Recent studies suggest that the quality of structural model and sedimentary facies model in the study area is good. However, the quality of attribute model is relatively poor, the score of the entire model is 78; the quality of entire model is medium, and there is still more room for this model improvement. The new geological model has been greatly improved compared with original geological model, the score of final model being 94. The quantitative evaluation of 3D geological model has not only the function of quantitative evaluation of model quality but also the advantage of defermining model's shortcoming, which can constantly improve the quality of the model.

Characteristics and Genesis of the Gypsum-mold Type Reservoir of the Majiagou Formation in the Sulige Gas Field

YU Haojie, ZHONG Shoukang, LI Fuping, XUE Wen, TIAN Qinghua

2021, 43(3):  71-80.  DOI: 10.11885/j.issn.16745086.2019.11.01.02

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Gypsum-mold-bearing micrite dolomite is an important reservoir type in the upper Ordovician Majiagou Formation in the Ordos Basin, and its formation time and genesis are important for the understanding of this reservoir type. In this research, based on the abundant core data of the study area, using the analysis of conventional physical properties and observation methods such as core, thin sections, the characteristics of the reservoir containing "gypsum-mold" and its genesis are comprehensively studied. The results show that the "gypsum-mold" is mainly developed in the micrite dolomite, which is located in the middle part of the shallowing upward sequence, and the two types of non-semi-filled and fully-filled types are often seen. As a reservoir, that mainly develops three kinds of reservoir spaces:residual pores in gypsum mold and interbedded pores in bedrock. The physical property test shows that this reservoir has superior performance, whose average porosity is 5.34%, and the average permeability is 1.02 mD. The dolomitic seepage silt similar to the composition of the bedrock is filled in the "gypsum-molds". The vertical sedimentary sequence shows that the development of the "gypsum-mold" is controlled by sedimentary cycles, the top of the cycles is characteristic of exposure, and the karst system can be seen poured with mud from the next transgression, all indicating that the formation of the "gypsum-mold" is related to the eogenetic karst, that is, the pore is formed in the early diagenetic stage, not the epigenetic stage of traditional understanding.

OIL AND GAS ENGINEERING

Effects of Particle Shape on the Meso-structure Stability of Fracture Plugging Zones

KANG Yili, JING Haoran, XU Chengyuan, YAN Xiaopeng, SHANG Xiangyu

2021, 43(3):  81-92.  DOI: 10.11885/j.issn.16745086.2020.12.20.02

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The stability of fracture plugging zone has a great impact on the lost circulation control effect in fractured reservoirs. To investigate the effect of particle shape on the stability of the mesoscopic structure of fracture plugging zone, polycarbonate particles with five different shapes are chosen for the photoelastic experiment. Photoelastic images of the simulated fracture plugging zone under shear loads are obtained to characterize the mesoscopic structure evolution of fracture plugging zone. The key parameters for the mesoscale structure characterization of fracture plugging zone are proposed based on the mean square gray gradient method, including the strong force chain and its orientation. The experimental results show that adding elliptic, equilateral triangular, square, and rectangular particles into fracture plugging zone formed by circular particles can make the structure of the force chain more varied and increase ring-like strong force chain. The contribution of long strip particles to the stability of the meso-structure of fracture plugging zone is larger than the regular polygon particles as the pressure fluctuation applies on the fracture plugging zone. The angular particles disperse the direction of force better than the circular ones, which makes the meso-structure of fracture plugging zone more stable. The effect of lost circulation control is improved when the proportion of angular and long strip particles is about 40% of rigid lost circulation materials (LCMs). Based on this understanding, the prescriptives of lost circulation control is adjusted, and the bearing capacity of the fracture plugging zone is enhanced. Field test of lost circulation control are successful once.

Production Simulation of Fractured Horizontal Well with Non-uniform Space Distribution of Fracture Conductivity in Shale Gas Reservoir

YANG Zhaozhong, LIAO Zijia, LI Xiaogang, ZHU Liyong, CHEN Hao

2021, 43(3):  93-100.  DOI: 10.11885/j.issn.16745086.2020.03.09.01

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The universal assumption in existing production prediction models of fractured horozontal well for shale gas reservoir is the evenly distribution of fracture conductivity. Therefore, there is a large deviation between the prediction production and real production. In order to improve the accuracy of production prediction for fractured gas well, a new model has been established based on point sink and superposition principle with consideration of the characteristic of non-uniform distribution of fracture conductivity. Numerical simulation studies show that the non-uniform distribution of fracture conductivity has a greater impact on production compared with the conventional model. Intensifying the fracture conductivity at nearside of wellbore with concave distribution could improve the yield after hydraulic fracturing when the dimensionless conductivity is small. With the increase of dimensionless conductivity, the increasing amplitude of yield decreases. Due to the limitation of supplying capacity of gas reservoir, the yield of gas well is similar under different patterns of conductivity distribution when the fracture conductivity reaches a certain level.

A Comprehensive Review of Enhanced Oil Recovery Technologies for Shale Oil

LI Yibo, HE Tianshuang, HU Zhiming, LI Yalong, PU Wanfen

2021, 43(3):  101-110.  DOI: 10.11885/j.issn.16745086.2020.04.07.01

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Through the investigation of the indoor research and field application of EOR technologies in shale oil reservoirs at home and abroad in the past 20 years, the difficulties in the development process are summarized in combination with the characteristics of shale oil reservoirs, and the adaptability of various EOR mechanisms to shale oil reservoirs. The results show:The gas injection is the best way to supply energy for shale reservoir. Carbon dioxide and natural gas are the normal injection media and the displacement mechanism needs further investigation. The wettability alteration to enhance the performance of imbibition effect is the main mechanism for surfactant and low salinity water flooding. Foam has the good performance in adjusting the heterogeneity but its stability needs to be enhanced. Thermal methods can change the thermal stress of the shale formation and thus induce the propagation of fracture to increase the sweep efficiency. In theory, solvent and nano-based material can also improve the wettability of shale reservoir, but its adaptation needs further discussion.

Determination Method of Oil Content of Water-based Drilling Cuttings in Shale Gas Development

LIANG Min, KONG Yanyan

2021, 43(3):  111-116.  DOI: 10.11885/j.issn.16745086.2020.03.25.01

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Taking the determination method of the oil content in waste water-based drilling cuttings in shale gas development for research object, tetrachloride and tetrachloroethylene are chosen as extraction agent in the extraction of oily substances in the simulated water-based drilling cutting under different extraction conditions (temperature, ultrasound power, reaction time, liquid/solid ratio) using ultrasound assisted extraction method; the oil content is analyzed by infrared oil content analyzer. The experimental results indicate that with the temperature of 25 ℃, the ultrasound power of 120 W, the reaction time of 20 min, and the liquid/solid ratio of 4 mL/g, the oil content reach above 9.6% with low deviations (<5%). The extraction efficiency of carbon tetrachloride is higher than that of tetrachloroethylene. By measuring the the oil content from on-site and simulated waste water-based drill cuttings and calculating the mark-up recovery and relative standard deviations (R_SD) for two types of samples, we get the mark-up recovery between 95%~105%, and the R_SD was less than 5%. Under the same extration condition, the result of test shows that oil content in water-based drilling cuttings extracted by the carbon tetrachloride coincide with that of tetrachloroethylene. Therefore, tetrachloroethylene, which is less harmful to the environment, was selected as the extraction agent for oil content test in water-based drilling cuttings, and the test results meet the test requirements.

Numerical Simulation of Plug Removal Effect of a Hydrate Self-heating Plug Removal Agent for Gas Well Production

DONG Shengwei, HE Aiguo, BAN Fansheng, DONG Jingnan

2021, 43(3):  117-127.  DOI: 10.11885/j.issn.16745086.2020.03.26.01

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In the later period of gas well production, blockage of the wellbore hydrates occurs frequently, and it is more important to remove the blockages of wellbore hydrates. According to the gas well hydrate blockage process and the characteristics of a certain type of self-generated thermal plugging agent, aiming at the problem of gas well hydrate blockage removal, a mathematical model for the decomposition rate of the gas hydrate blockage section and a heat transfer mathematical model were established. The simulation calculation of hydrate plugging removal process in wellbore was carried out, and the distribution cloud map of temperature, water volume fraction and other parameters in the process of plugging removal with different concentrations of plug removal agent were obtained, and the amount of plugging removal agent and the plugging removal time under different concentrations of autogenous pyrolysis plugging agent were obtained. An experimental study on the deblocking process under different concentrations of deblocking agent was carried out. The amount of deblocking agent and the time required for deblocking under different concentrations of autogenous thermal deblocking agent were measured in the experiment. The simulation calculation value and experimental value of the amount of unblocking agent and the unblocking time are more than 80%. The study found that as the concentration of the plugging agent increases, the plugging time decreases and the amount of plugging agent decreases. However, when the concentration of the anti-plugging agent exceeds 2.0 mol/L, the improvement of its anti-plugging effect is relatively reduced.

Research and Performance Evaluation of Cementing Anti-channeling Toughening Agent Under Dynamic Pressure

XU Bihua, TANG Lei, XU Kun, XU Deyang, LI Zhiheng

2021, 43(3):  128-135.  DOI: 10.11885/j.issn.16745086.2020.02.26.02

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During the cementing process of adjustment well, the formation pressure is always in a state of fluctuation, which leads to serious water channeling; in addition, when the reservoir is reformed, the fracture of cement sheath will result in annulus channeling. In view of the above problems existing in the cementing of adjustment wells, a kind of anti channeling and toughening agent for cementing under dynamic pressure was prepared by optimizing the anti channeling and toughening materials. Then, according to the characteristics of water channeling under dynamic pressure, a new self-developed water channeling evaluation device is used to evaluate the water channeling performance of the modified cement slurry. In addition, the expansion property, mechanical property and engineering performance of the modified cement paste were evaluated. Finally, the field test was carried out in Bohai Oilfield. The results show that the agent enhances the anti dynamic water dispersion performance of cement slurry and the anti-water channeling performance of cemented interface of cement paste, reduces the water loss and volume shrinkage; at the same time, the agent significantly improves the toughness of cement paste, and has no negative impact on the engineering performance of cement slurry; the field test results show that the cementing quality is better than that of adjacent wells. The results show that the anti channeling and toughening agent can meet the requirements of cementing anti channeling and toughening under dynamic pressure.

A Study on Seepage Characteristics and Productivity of Fractured Tight Reservoir Chang 3 in Weibei

WU Jinwei, LI Yongren, CAO Jun, Lü Dongliang

2021, 43(3):  136-145.  DOI: 10.11885/j.issn.16745086.2019.10.28.02

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In order to study the seepage characteristics of matrix and natural fracture system and its effect on productivity, We taking the typical fractured tight reservoir of Chang 3 in Wubei Oilfield as the research object, and through the nuclear magnetic resonance and the laboratory test synthesis experiment, the variation of reservoir seepage pressure gradient, the variation of matrix and fracture core pore structure with confining pressure and the variation of matrix and fracture core porosity with effective stress and stress sensitivity coefficient are determined. A multi-stage fracture horizontal well productivity model considering the initiation pressure gradient, matrix and fracture stress sensitivity differences is established and validated. The effects of starting pressure gradient, matrix and crack stress sensitivity on productivity are analyzed. The results show that the quasi-starting pressure gradient increases with the decrease of core fluidity; the porosity stress sensitivity and permeability sensitivity of fracture core are stronger than that of matrix core; the stress sensitivity of matrix has a more significant effect on productivity. Therefore, the effect of decreasing stress sensitivity and starting pressure gradient should be considered in the effective development of Chang-3 fractured tight reservoir in Weibei Oilfield.

An Experimental Study on Steam Flooding After Huff and Puff in Deep Super Heavy Oil Reservoir

ZHAO Qinghui, ZHANG Hong, YANG Xingchao, CHENG Haiqing, PAN Pan

2021, 43(3):  146-154.  DOI: 10.11885/j.issn.16745086.2020.03.24.02

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The deep super heavy oil reservoir in Shu1 area of Liaohe Oilfield has been developed by steam stimulation for many years, and has achieved certain development results. However, after entering into mid-and late stage of huff and puff, it is faced with the problems of low cycle oil production, low oil steam ratio, increasing difficulty of stable production, etc., so it is urgent to study the replacement technology after steam stimulation. In this paper, the influence factors, control strategies and production characteristics of steam flooding after huff and puff are studied by using the high temperature and high pressure proportional physical simulation device. The results show that the characteristics of temperature field formed in the steam huff and puff stage have great influence on the subsequent steam flooding development. The preconditions for steam stimulation to steam flooding are:first, the temperature of thermal connection between injection and production wells should be above the critical temperature of crude oil; second, the volume of steam cavity cultivated in the stimulation stage should be large enough, and the lateral sweep should be about one third of the injection production well spacing; the adjustment of injection production well section is an important factor to improve the effect of steam flooding. For the case that there is no stable interlayer in the layer, the steam injection in the lower 1/2 well section can effectively restrain the steam body overlap and improve the recovery degree. When the steam flooding reaches the stage of denudation production, adjusting the production well from the whole well section to the lower 1/2 well section can enlarge the wave and volume to a certain extent and improve the recovery degree; the production characteristics of super heavy oil steam drive are mainly denudation, supplemented by displacement. The results provide a theoretical basis for the optimization design of the development plan and field test after steam stimulation in deep super heavy oil reservoir.

Optimization of a Bottom-hole Pressure Correction Model Using K-means Clustering

ZHANG He, QUAN Rui

2021, 43(3):  155-164.  DOI: 10.11885/j.issn.16745086.2019.01.14.03

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In the process of drilling, owing to problems such as data distortion during the measurement of bottom-hole pressure, absence of return data, and incapacity of bottom-hole pressure calculation models to accurately reflect the measurements, the bottom-hole pressure cannot be accurately monitored, and this results in a substantial safety risk for drilling operations. To provide an effective overall monitoring of the bottom-hole pressure, a K-means clustering optimization method was established to improve the Naive Bayesian model. Combined with the principle of bottom-hole pressure monitoring, a Naive Bayesian model optimized by K-means clustering was designed, which could perform intelligent dynamic analysis of the bottom-hole pressure. This model was adopted to correct the bottom-hole pressure calculated by the traditional hydraulic model, and the results of both these models were compared to minimize the calculation error. Analysis of field data suggested that the calculated bottom-hole pressure corrected using the optimized model demonstrated a smaller error. This error was within the safe range of the pressure monitoring of drilling operation, indicating that the model was able to satisfy the requirements of regular drilling practices.

PETROLEUM MACHINERY AND OILFIELD CHEMISTRY

The Technology of “Adjustment + Displacement + Water Plugging + Fracturing” Using Polymer-surfactant Agent After Polymer Flooding

HE Jingang, YUAN Lin

2021, 43(3):  165-174.  DOI: 10.11885/j.issn.16745086.2020.01.15.02

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In view of the problem that 43.7% reserves remain underground after polymer flooding in the main oil layer of Daqing Oilfield, the adjustment technology of "Adjustment + Displacement + Water Plugging + Fracturing" using polymer-surfactant agent after polymer flooding is studied. By the means of laboratory physical simulation, reservoir numerical simulation and dynamic analysis of field test, the technology of "Adjustment + Displacement + Water Plugging + Fracturing" and its feasibility are put forward and demonstrated. "Adjustment" is first of all the well pattern adjustment for the purpose of adjusting the seepage direction, exploiting the residual oil in the diverging line and increasing the displacement pressure gradient. The second step of "Adjustment" is "Profile Control" in which seperated layer injection is implemented as soon as possible, and conflicts between layers is alleviated by stepwise injection. The 0.3 PV polymer-surfactant agent type I (concentration:2 000 mg/L) is injected, and its association is used to play a dynamic viscosity increasing role to alleviate in-layer contradictions. "Displacement" is using 0.7 PV polymer-surfactant agent type II (concentration:1 000 mg/L), which is injected with step-down viscosity and increased rate, and is adjusted accordingly to development dynamics. "Water Plugging" is forming emulsified oil type plugging, by using the polymer-surfactant agent type II. "Fracturing" is moderate fracturing, that releases the emulsified remaining oil, side interlining barrier remaining oil on top reservoir and thin layer emulsified residual oil. The field test shows that the EOR is more than 9% with good economic benefits. It is expected to be a new way of EOR technology after polymer flooding.

Design of an Intelligent Fouling-getting System in Natural Gas Well with High Sulfur Content

LIN Lijun, HE Mingge, MA Zihan

2021, 43(3):  175-182.  DOI: 10.11885/j.issn.16745086.2020.04.23.01

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In the production process of oil and gas Wells, due to the comprehensive influence of various factors such as geological environment, production stage and mineral composition, it is easy to form scale and blockage on the wellbore, which will affect production. The effectiveness of plugging removal methods and technological measures is directly determined by whether the downhole scale sample can be obtained. An intelligent downhole scaling system was designed and developed for the sampling of downhole scaling materials in gas wells with high sulfur content. The architecture and working principle of the intelligent downhole scaling device were introduced. The key mechanical structures and components of the scale remover, such as the circuit board damping structure, the scale remover claw, the scale basket device and the centralizing device, are discussed in detail. The architecture and control principle of electrical timing control system based on DSP are expounded, and the key parameters calculation process of PID control algorithm is emphatically illustrated. The results of indoor performance tests and well function tests show that the temperature and pressure resistance of the developed tool, as well as the automatic telescopic and synchronous control function of the scaling device are reliable, and the well entry and exit processes are smooth, which can provide equipment support for the accurate sampling of the scale in the gas well with high sulfur content. At the same time, the proposed design method and idea have certain reference significance to the research and development of other intelligent downhole tools.