CO2 Sequestration-EOR in a Tight Oil Reservoir: Estimation of Dynamic CO2 Storage Capacity Using a Two-Stage Well Test

Abstract The technology of Stimulated reservoir volume (SRV) has been the key technology for unconventional reservoir development, it can create fracture network in formation and increase the contact area between fracture surface and matrix, thus realizing the three-dimensional stimulation and enhancing single well productivity and ultimate recovery. In China, the Ordos Basin contains large areas of tight oil reservoir with the porosity of 2~12 % and permeability of 0.01~1 mD. The most used development mode is conventional fracturing and water flooding, which is different from the natural depletion mode in oversea, but the development effect is still unfavorable. The idea of SRV is proposed in nearly two years in Changqing Oilfield. SRV measures are implemented in some old wells in tight oil formation. It is a significant problem that should be solved urgently about how to evaluate the volume fracturing effect. Based on the real cases of old wells with SRV measures, the microseismic monitoring is used to analyze the scale of formation stimulation and the complexity of fracture network after volume fracturing; the numerical well test and production data analysis (PDA) are selected to explain the well test data, to analyze the dynamic data, and to compare the changes of formation parameters, fluid parameters and plane streamlines before and after volume fracturing; then the interpretation results of well test with the dynamic of oil and water wells are combined to evaluate the stimulation results of old wells after SRV. This paper has presented a set of screening criteria and an evaluation method of fracturing effect for old well with SRV in tight oil reservoir. It will be helpful to the selection of candidate well and volume fracturing operation in Ordos Basin tight oil reservoir. It should be noted that the evaluation method mentioned in the paper can be expanded to volume stimulation effect evaluation in other unconventional reservoirs, such as tight gas, shale gas and so on.

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Hydraulic Fracturing of Ultrahigh Stress Tight Oil Reservoir - A Case Study of Yumen Oilfield in China

10.2523/18752-ms ◽

2016 ◽

Author(s):

Peng Yi ◽

Weng Dingwei ◽

Xu Yun ◽

Wang Liwei ◽

Lu Yongjun ◽

...

Keyword(s):

Hydraulic Fracturing ◽

Tight Oil ◽

Oil Reservoir ◽

Tight Oil Reservoir

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Production capacity prediction model for multi-stage fractured horizontal well coupled with imbibition in tight oil reservoir

JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING ◽

10.3724/sp.j.1249.2018.04345 ◽

2018 ◽

Vol 35 (4) ◽

pp. 345 ◽

Cited By ~ 1

Author(s):

Yuliang SU ◽

Xiuhong HAN ◽

Wendong WANG ◽

Guanglong SHENG ◽

Zhengming YANG ◽

...

Keyword(s):

Prediction Model ◽

Horizontal Well ◽

Production Capacity ◽

Tight Oil ◽

Oil Reservoir ◽

Multi Stage ◽

Fractured Horizontal Well ◽

Tight Oil Reservoir ◽

Capacity Prediction

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Fine Geological Modeling of the Tight Oil Reservoir

Acta Geologica Sinica - English Edition ◽

10.1111/1755-6724.12302_28 ◽

2015 ◽

Vol 89 (s1) ◽

pp. 65-66

Author(s):

Hongru LIANG ◽

Shuangfang LU ◽

Mingming TANG ◽

Bihui YAN ◽

Shan SHEN

Keyword(s):

Tight Oil ◽

Oil Reservoir ◽

Geological Modeling ◽

Tight Oil Reservoir

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Numerical Simulation and Optimization of CO2 Sequestration in Saline Aquifers

ASME 2012 6th International Conference on Energy Sustainability, Parts A and B ◽

10.1115/es2012-91006 ◽

2012 ◽

Cited By ~ 1

Author(s):

Zheming Zhang ◽

Ramesh Agarwal

Keyword(s):

Numerical Simulation ◽

Co2 Sequestration ◽

Storage Capacity ◽

Co2 Storage ◽

Injection Well ◽

Co2 Injection ◽

Great Promise ◽

Saline Aquifer ◽

Simulation And Optimization ◽

Co2 Plume

With recent concerns on CO2 emissions from coal fired electricity generation plants; there has been major emphasis on the development of safe and economical Carbon Dioxide Capture and Sequestration (CCS) technology worldwide. Saline reservoirs are attractive geological sites for CO2 sequestration because of their huge capacity for sequestration. Over the last decade, numerical simulation codes have been developed in U.S, Europe and Japan to determine a priori the CO2 storage capacity of a saline aquifer and provide risk assessment with reasonable confidence before the actual deployment of CO2 sequestration can proceed with enormous investment. In U.S, TOUGH2 numerical simulator has been widely used for this purpose. However at present it does not have the capability to determine optimal parameters such as injection rate, injection pressure, injection depth for vertical and horizontal wells etc. for optimization of the CO2 storage capacity and for minimizing the leakage potential by confining the plume migration. This paper describes the development of a “Genetic Algorithm (GA)” based optimizer for TOUGH2 that can be used by the industry with good confidence to optimize the CO2 storage capacity in a saline aquifer of interest. This new code including the TOUGH2 and the GA optimizer is designated as “GATOUGH2”. It has been validated by conducting simulations of three widely used benchmark problems by the CCS researchers worldwide: (a) Study of CO2 plume evolution and leakage through an abandoned well, (b) Study of enhanced CH4 recovery in combination with CO2 storage in depleted gas reservoirs, and (c) Study of CO2 injection into a heterogeneous geological formation. Our results of these simulations are in excellent agreement with those of other researchers obtained with different codes. The validated code has been employed to optimize the proposed water-alternating-gas (WAG) injection scheme for (a) a vertical CO2 injection well and (b) a horizontal CO2 injection well, for optimizing the CO2 sequestration capacity of an aquifer. These optimized calculations are compared with the brute force nearly optimized results obtained by performing a large number of calculations. These comparisons demonstrate the significant efficiency and accuracy of GATOUGH2 as an optimizer for TOUGH2. This capability holds a great promise in studying a host of other problems in CO2 sequestration such as how to optimally accelerate the capillary trapping, accelerate the dissolution of CO2 in water or brine, and immobilize the CO2 plume.

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