왕지훈 교수

Carbon capture and sequestration (CCS) method is the only viable method for reducing massive amount of carbon dioxide (CO2) from the atmosphere to prevent the subsequent environmental and health threats. However, the process is accompanied with geomechanical risks due to the unavoidable pore pressure buildup, such as caprock failure, reactivation of existing faults, poroelastic response of rock and well integrity loss. Not only may the risks lead to undesirable environmental concerns such as CO2

The CO₂ trap mechanisms during carbon capture and storage (CCS) are classified into structural, residual, solution, and mineral traps. The latter is considered as the most permanent and stable storage mechanism as the injected CO₂ is stored in solid form by the carbon mineralization. In this study, the carbon mineralization process in geological CO₂ storage in basalt, sandstone, carbonate, and shale are reviewed. In addition, relevant studies related to the carbo

Electrical submersible pump (ESP) operation is compromised by free gas, resulting in premature pump failure and production losses in new wells. It is essential to detect the onset of abnormal operations. We develop a model that predicts abnormal ESP operation when the free gas level increases in the pump. The model compares operation parameters with the parameters of normal operating ranges; it shuts down the ESP when necessary. We used a Schlumberger PIPESIM software (version 2017.01) to perfor

This study aims at the development of an artificial neural network (ANN) model to optimize relief well design in Pohang Basin, South Korea. Relief well design in carbon capture and geological storage (CCS) requires complex processes and excessive iterative procedures to obtain optimal operating parameters, such as CO2 injection rate, water production rate, distance between the wells, and pressure at the wells. To generate training and testing datasets for ANN model development, optimization proc

CO 2 -Enhanced Oil Recovery (CO 2 -EOR) is an effective development strategy and an economically viable CO 2 storage method for a mature oil field. In this study, a smart proxy model (SPM) was constructed to establish the optimal development strategies in Farnsworth Unit (FWU) considering CO 2 storage and oil production with the production-injection well conversion. An SPM was constructed with the results of 16 reservoir simulations and was validated with an R 2 values of 96.3 % and 97.5 % for t

Most shale gas reservoirs have extremely low permeability. Predicting their fluid transport characteristics is extremely difficult due to complex flow mechanisms between hydraulic fractures and the adjacent rock matrix. Recently, studies adopting the dynamic modeling approach have been proposed to investigate the shape of the flow regime between induced and natural fractures. In this study, a production history matching was performed on a shale gas reservoir in Canada’s Horn River basin. Hypocen

This study presents a new interface for wellbore stability analysis, which visualizes and quantifies the stress condition around a wellbore at shear and tensile failure. In the first part of this study, the Mohr–Coulomb, Mogi–Coulomb, modified Lade and Drucker–Prager shear failure criteria, and a tensile failure criterion, are applied to compare the differences in the critical wellbore pressure for three basin types with Andersonian stress states. Using traditional wellbore stability window plot

Polymers play an important role in hybrid enhanced oil recovery (EOR), which involves both a polymer and low-salinity water. Because the polymer commonly used for low-salinity polymer flooding (LSPF) is strongly sensitive to brine pH, its efficiency can deteriorate in carbonate reservoirs containing highly acidic formation water. In this study, polymer efficiency in an acidic carbonate reservoir was investigated experimentally for different salinity levels and SO42− concentrations. Results indic

In this paper an improved block truncation coding (IBTC) using low cost approach is presented for color image compression. To reduce the bit rate of the basic BTC, selected single bit-map is employed to represent the edge information of the coding block in the proposed IBTC. Moreover, a previous proposed algorithm, adaptive quantization coding (AQC), is used to compress the two representative levels further. Simulation results show that the proposed IBTC reduces the line buffer memory usage to a

The purpose of this study is to investigate the effect of principal stress direction on the efficiency of hydraulic fracturing treatment. There are two different drilling scenarios: 1. Four horizontal wells drilled in four orthogonal directions regardless of in-situ stress condition (“Actual”). 2. Three horizontal wells drilled equivalent to “Actual” case by considering the direction of principal stress (“Proposed”). The hydraulic fracturing modeling was carried out based on well logging data an

In this study, the multi-stage triaxial compression testing method is adopted to obtain geomechanical parameters without heterogeneity effect. Using the geomechanical characterisation we calculate various brittleness indices previously suggested in the literature. Before the triaxial test and after the ultimate rock failure, we also measure the permeability enhancement ratio caused by rock failure with characteristic time obtained from pulse decay permeameter. Analysing the relationship between