scholarly journals Hydrocarbon Gas Flooding Optimization considering Complex Fracture Networks through Numerical Simulation in the Tight Oil Reservoirs

Lithosphere ◽  
2021 ◽  
Vol 2021 (Special 4) ◽  
Author(s):  
Yong Qin ◽  
Haochuan Zhang ◽  
Chang Liu ◽  
Haifeng Ding ◽  
Tianyu Liu ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Gas Injection ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Oil Reservoir ◽  
Fracture Networks ◽  
Complex Fracture ◽  
Gas Flooding ◽  
Hydrocarbon Gas ◽  
Tight Oil Reservoirs

Abstract Field data indicates that oil production decline quickly and the oil recovery factor is low due to low permeability and insufficient energy in the tight oil reservoirs. Enhanced oil recovery (EOR) is required to improve the oil production rates of tight oil reservoirs. Gas flooding is a good means to supplement formation energy and improve oil recovery factor, especially for hydrocarbon gas flooding when CO2 is insufficient. Due to the permeability in some areas is too low, the injected gas cannot spread farther, and the EOR performance is poor. So multifractured horizontal well (MFHW) are usually used to assist gas injection in oilfields. At present, there are few studies on the optimization of hydrocarbon gas flooding parameters especially under the complex fracture network. This article uses unstructured grids to characterize the complex fracture networks, which more realistically shows the flow of formation fluids. Based on actual reservoir data, this paper establishes the numerical model of hydrocarbon gas flooding under complex fracture networks. The article conducts numerical simulation to analyze the effect of different parameters on well performance and provides the optimal injection and production parameters for hydrocarbon gas flooding in the M tight oil reservoir. The optimal injection-production well spacing of the M tight oil reservoir is about 800 to 900 m. The EOR performance is better when the total gas injection rates are about 0.45 HCPV, and gas injection rates of each well are about 3000 to 3500 m3/d (0.021 to 0.025 HCPV/a). The recommended injection-production ratio is about 1.1 to 1.2. This work can offer engineers guidance for hydrocarbon gas flooding of the MFHW with complex fracture networks. Hydrocarbon gas flooding in tight oil reservoirs can enhance oil recovery. The findings of this study can help for a better understanding of the influence of different parameters on hydrocarbon gas flooding in the M tight oil reservoir. This work can also offer engineers guidance for hydrocarbon gas flooding of the MFHW with complex fracture networks.

scholarly journals Optimization of triple-alternating-gas (TAG) injection technique for enhanced oil recovery in tight oil reservoirs

2021 ◽  
Author(s):  
Mvomo Ndzinga Edouard ◽  
Pingchuan Dong ◽  
Chinedu J. Okere ◽  
Luc Y. Nkok ◽  
Abakar Y. Adoum ◽  
...  
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Gas Injection ◽  
Oil Reservoirs ◽  
Recovery Factor ◽  
Injection Technique ◽  
Tight Oil ◽  
Compositional Model ◽  
Injection Scheme ◽  
Tight Oil Reservoirs

AbstractAfter single-gas (SG) injection operations in tight oil reservoirs, a significant amount of oil is still unrecovered. To increase productivity, several sequencing gas injection techniques have been utilized. Given the scarcity of research on multiple-gas alternating injection schemes, this study propose an optimized triple-alternating-gas (TAG) injection for improved oil recovery. The performance of the TAG process was demonstrated through numerical simulations and comparative analysis. First, a reservoir compositional model is developed to establish the properties and composition of the tight oil reservoir; then, a suitable combination for the SG, double alternating gas (DAG), and TAG was selected via a comparative simulation process. Second, the TAG process was optimized and the best case parameters were derived. Finally, based on the oil recovery factors and sweep efficiencies, a comparative simulation for SG, DAG, and TAG was performed and the mechanisms explained. The following findings were made: (1) The DAG and TAG provided a higher recovery factor than the SG injection and based on recovery factor and economic advantages, CO2 + CH4 + H2S was the best choice for the TAG process. (2) The results of the sensitivity analysis showed that the critical optimization factors for a TAG injection scheme are the injection and the production pressures. (3) After optimization, the recovery factor and sweep efficiency of the TAG injection scheme were the best. This study promotes the understanding of multiple-gas injection enhanced oil recovery (EOR) and serves as a guide to field design of gas EOR techniques.

Modeling tracer flowback in tight oil reservoirs with complex fracture networks

2017 ◽  
Vol 157 ◽  
pp. 1007-1020 ◽  
Author(s):  
Linkai Li ◽  
Hanqiao Jiang ◽  
Junjian Li ◽  
Keliu Wu ◽  
Fanle Meng ◽  
...  
Keyword(s):  
Oil Reservoirs ◽  
Tight Oil ◽  
Fracture Networks ◽  
Complex Fracture ◽  
Tight Oil Reservoirs

scholarly journals Tight oil reservoir production characteristics developed by CO2 huff ‘n’ puff under well pattern conditions

2022 ◽  
Author(s):  
Zhizeng Xia ◽  
Xuewu Wang ◽  
Rui Xu ◽  
Weiwei Ren
Keyword(s):  
Physical Properties ◽  
Oil Recovery ◽  
Oil Reservoirs ◽  
Injection Timing ◽  
Tight Oil ◽  
Oil Reservoir ◽  
Natural Energy ◽  
Tight Oil Reservoir ◽  
Tight Oil Reservoirs ◽  
Production Characteristics

AbstractTight oil reservoirs have poor physical properties, and the problems including rapid oil rate decline and low oil recovery degree are quite common after volume fracturing. To obtain a general understanding of tight oil reservoir production improvement by CO2 huff ‘n’ puff, the high-pressure physical properties of typical tight oil samples are measured. Combining the typical reservoir parameters, the production characteristics of the tight oil reservoir developed by the CO2 huff ‘n’ puff are numerically studied on the basis of highly fitted experimental results. The results show that: (1) during the natural depletion stage, the oil production rate decreases rapidly and the oil recovery degree is low because of the decrease in oil displacement energy and the increase in fluid seepage resistance. (2) CO2 huff ‘n’ puff can improve the development effect of tight oil reservoirs by supplementing reservoir energy and improving oil mobility, but the development effect gradually worsens with increasing cycle number. (3) The earlier the CO2 injection timing is, the better the development effect of the tight reservoir is, but the less sufficient natural energy utilization is. When carrying out CO2 stimulation, full use should be made of the natural energy, and the appropriate injection timing should be determined by comprehensively considering the formation-saturation pressure difference and oil production rate. The research results are helpful for strengthening the understanding of the production characteristics of tight oil reservoirs developed by CO2 huff ‘n’ puff.

Huff-n-Puff Technology for Enhanced Oil Recovery in Shale/Tight Oil Reservoirs: Progress, Gaps, and Perspectives

2021 ◽  
Author(s):  
Muhend Milad ◽  
Radzuan Junin ◽  
Akhmal Sidek ◽  
Abdulmohsin Imqam ◽  
Mohamed Tarhuni
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Tight Oil Reservoirs

A Critical Review of CO2 Enhanced Oil Recovery in Tight Oil Reservoirs of North America and China

2019 ◽  
Author(s):  
Zhaojie Song ◽  
Yuzhen Li ◽  
Yilei Song ◽  
Baojun Bai ◽  
Jirui Hou ◽  
...  
Keyword(s):  
North America ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Critical Review ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Tight Oil Reservoirs

scholarly journals Simulation of High Water-Cut in Tight Oil Reservoirs during Cyclic Gas Injection

2019 ◽  
Author(s):  
Chi Zhang ◽  
Ye Tian ◽  
Yizi Shen ◽  
Bowen Yao ◽  
Yu-Shu Wu
Keyword(s):  
Gas Injection ◽  
High Water ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Tight Oil Reservoirs ◽  
High Water Cut ◽  
Water Cut

Effects of Water Immersion and Acidification on Nano-Pores in Tight Sandstones—A Case Study of the Gaotaizi Reservoir, Songliao Basin

2021 ◽  
Vol 21 (1) ◽  
pp. 615-622
Author(s):  
Min Wang ◽  
Chenxue Jiao ◽  
Nengwu Zhou ◽  
Chuanming Li ◽  
Mingming Tang ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Water Immersion ◽  
Songliao Basin ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Core Flooding ◽  
Carbonate Minerals ◽  
Tight Sandstone ◽  
Content Type ◽  
Tight Oil Reservoirs

Hydraulic fracturing and acidification are among the most commonly used methods for stimulating the tight oil reservoirs and improving oil recovery. Therefore, examining the effects of water immersion and acidification on tight oil reservoirs is important for oilfield development plans. Core flooding testing, which analyzes the influence of core permeability variations before and after acid injection on the reservoir quality, is the conventional research method; however, it is difficult to observe the changes in minerals and pores caused by acidulation and water immersion in situ. In this study, we conduct field-emission scanning electron microscopy (FE-SEM), MAPS, the quantitative evaluation of minerals through scanning electronic microscopy (QEM-SCAN), and describe the types of pores in tight sandstone. Further, the effects of water immersion and acidification on pores in tight sandstone were studied. The results indicate that: (1) intergranular pores, intragranular dissolution pores, clay mineral intercrystalline pores, and micro-cracks were developed in the Gaotaizi tight sandstone in Songliao Basin, with the intergranular pores observed to be dominant; (2) the hydration of clay minerals induced by water injection caused plugging of pores at the nanometer– micrometer scale, and plane porosity is slightly reduced (˜0.86%); (3) acidification resulted in the dissolution of carbonate minerals, increasing the porosity of the reservoir, therefore, the increase in porosity is influenced by the carbonate mineral content. We recommend that future studies should investigate the content, type, and distribution of carbonate minerals in the operation area. During the process of reservoir stimulation, such as acidification and CO2 injection- and-production, the influence of carbonate minerals dissolution on oil production should be considered.

scholarly journals Simulation Study of CO2-EOR in Tight Oil Reservoirs with Complex Fracture Geometries

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Pavel Zuloaga-Molero ◽  
Wei Yu ◽  
Yifei Xu ◽  
Kamy Sepehrnoori ◽  
Baozhen Li
Keyword(s):  
Simulation Study ◽  
Oil Reservoirs ◽  
Tight Oil ◽  
Complex Fracture ◽  
Co2 Eor ◽  
Tight Oil Reservoirs
Sign in / Sign up

Export Citation Format

Share Document