Experimental study of the fracture initiation through the synergy of spontaneous imbibition and hydration of residual fracturing fluids in shale gas reservoirs

Zhou, Yang; You, Lijun; Kang, Yili; Xie, Benbin; Cheng, Qiuyang

doi:10.1016/j.jngse.2022.104577

Cited by 13 publications

(13 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the correlation between the DI water SI slope and the geometric tortuosity is weak, which may be related to the water–rock interaction. The imbibition of water could cause a certain degree of dissolution of soluble minerals in shale samples to form a new storage space and migration pathway, which can accelerate the SI process of water …”

Section: Resultsmentioning

confidence: 99%

“…The water–rock interaction between soluble minerals in the rock and water will affect the SI of water. More specifically, the soluble minerals in the rock are partially dissolved by the reaction with water, which has a certain effect on the SI of water, − and the previous studies’ results show that the salinity of water also has a great influence on SI. − In addition, clay minerals typically swell to a certain extent when in contact with water, complicating the pore structure of shale (e.g., blocking pores and throats) and sometimes reducing fluid migration rates. , For homogeneous porous media, the greater the tortuosity of the connected pore system, the longer the migration path of solute molecules through the same linear distance in the porous medium and the smaller the imbibition slope . Due to the strong heterogeneity and complex pore structure of shale with the coexistence of organic matter pores and inorganic pores, shale reservoirs often exhibit mixed wettability (Dalmatian wettability), which in turn affects the SI behavior. , The wettability and pore connectivity of shale reservoirs were previously evaluated by SI experiments. , However, the application of SI on the enrichment mechanism of hydrocarbons is quite limited.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Using Spontaneous Imbibition to Evaluate the Hydrocarbon Migration and Accumulation Potential of Shale Reservoirs: A Case Study of the Permian Fengcheng Formation in the Mahu Sag, Junggar Basin

Wang

Gao

et al. 2022

Energy Fuels

View full text Add to dashboard Cite

Spontaneous imbibition (SI) has been used widely to characterize shale wettability and pore structures, which can significantly affect the migration and accumulation processes of shale oil. However, the application of SI in the enrichment mechanism of shale oil is quite limited. Therefore, focusing on the Permian Fengcheng Formation shale deposited in an alkaline lake environment in the Mahu Sag of Junggar Basin, this study conducts systematic SI experiments with complementary experiments such as contact-angle measurement, optical microscopy, field emission scanning electron microscopy, micro-CT, high-pressure mercury intrusion porosimetry, and N 2 adsorption to clarify the controlling factors of SI behavior of different fluids in shale and attempts to evaluate the migration and accumulation potential of shale reservoirs using SI. The results show that the more hydrophobic the sample is, the stronger the absorption of n-decane is, and the SI of n-decane reaches equilibrium quickly. The development of an alkaline mineral layer that is several millimeters thick in Fengcheng Formation shale could promote hydrocarbon migration due to the large particles of alkaline minerals (200−400 μm) and more development of intergranular microfractures, which can be indicated by the higher SI slope and imbibed oil volume. Using SI parameters, the shale hydrocarbon migration−accumulation index H m was proposed in this study; the greater the H m of the shale reservoir is, the more conducive to the migration and accumulation of shale oil the shale reservoir is. Four migration−accumulation patterns were established for different lithofacies in the study area, and the migration and accumulation potential of different lithofacies of shale from strong to weak is in the order of siltstone, shale with an alkaline mineral layer, laminated shale, and then massive shale, which is generally in line with the order of shale oil content. The validity of the proposed shale hydrocarbon migration−accumulation index is also confirmed using data from the literature.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Using Spontaneous Imbibition to Evaluate the Hydrocarbon Migration and Accumulation Potential of Shale Reservoirs: A Case Study of the Permian Fengcheng Formation in the Mahu Sag, Junggar Basin

Wang

Gao

et al. 2022

Energy Fuels

View full text Add to dashboard Cite

show abstract

“…In Figure 25a−c, the distribution of pressure after 365 days is indicated, where the influence of shut-in is evident as it increases the area of contact. 178 Shut-in has a positive effect on gas production, and where there is formation damage due to the impact of shut-in, still, the reduction in production is minimal; 178 and when shut-in is ignored, the production reduces as shown in Figure 25d. This is mainly because of the fact that shale is in total contact with the fracturing fluid before shut-in, and the later stages of imbibition have limited impact on the depth of imbibition, which minimizes the effect of additional formation damage due to shut-in.…”

Section: Flow Of Gas From the Naturalmentioning

confidence: 99%

“…This is mainly because of the fact that shale is in total contact with the fracturing fluid before shut-in, and the later stages of imbibition have limited impact on the depth of imbibition, which minimizes the effect of additional formation damage due to shut-in. Also, during the shut-in, water disperses under the action of capillary forces, thereby leading to a decrease in water saturation around the fracture region and, thus, reducing formation damage, 178 as shown in Figure 25e. Finally, in Figure 25f, the effect of shut-in is reflected, where the reduction in pressure as a result of production reduces with the increase in soaking time, which indicates that there is an increase in the relative permeability.…”

Section: Flow Of Gas From the Naturalmentioning

confidence: 99%

Hydraulic Fracturing and Enhanced Recovery in Shale Reservoirs: Theoretical Analysis to Engineering Applications

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

Shale reservoirs are extensively exploited using hydraulic fracturing, which forms multiple cracks that connect with the existing natural fractures to create a continuous path for the gas stored in the kerogen to flow to the production well. Apart from the tedious nature of hydraulic fracturing, the mechanism of the storage and flow of gas is equally complex since multiple phases and scales are involved. An accurate understanding of hydraulic fracturing coupled with a strategy of analyzing the flow and overall recovery of gas is paramount to ensure efficient exploitation. In this work, a comprehensive review of the recent strategies used in analyzing the hydraulic fracturing, storage, flow, and recovery of gas is presented. To begin with, the experimental, analytical, and numerical approaches pertinent to hydraulic fracturing are deeply explored. Additionally, the flow of gas through the newly opened channels is accounted for by using a quadruple-domain approach where the mechanisms of flow in shale reservoirs at the nanoscale, microscale, mesoscale, and macroscale are considered. Furthermore, a strategy to capture the multiple phases, including gas, oil, and water, and recover both carbon dioxide and methane is explored through thermal and enhanced gas recovery approaches. This review provides a baseline for understanding how the hydraulic fracture evolves and propagates to create new channels that contribute to the flow of gas, how the gas flows through the created channels across the many scales of the shale reservoir, and how to improve recovery from shale reservoirs.

show abstract

“…13 A large number of studies have also confirmed that residual fracturing fluid can promote fracture propagation through water−rock interaction during shut-in. 14 Based on this, researchers demonstrated the feasibility of utilizing the positive effect of residual fracturing fluid to create fractures by reducing the amount of flowback fluid and believed that this was a feasible strategy for the efficient development of shale gas reservoirs. 15 In this paper, the oxidative stimulation method is proposed.…”

Section: Introductionmentioning

confidence: 99%

Study on Formation Damage of Fracturing and Its Prevention through an Environmentally Friendly Method of Oxidative Stimulation in Shale Gas Reservoirs

et al. 2022

Self Cite

View full text Add to dashboard Cite

Large amounts of fracturing fluid remain in the reservoir after fracturing, rendering it easy to induce reservoir damage and restrict the stimulation effect. Based on the idea of less flowback of fracturing fluid and considering the characteristics of abundant organic matter and pyrite in shale gas reservoirs, an environmentally friendly method of oxidative stimulation is proposed. Through experimental verification and theoretical analysis, it is found that the oxidative stimulation method has a good application prospect in shale reservoirs. By adding an oxidant to the prefrac fluid, the oxidative stimulation can increase the porosity, enlarge the pore size, promote the imbibition capacity of the shale gas reservoir, and prevent the water trapping damage and stress-sensitive damage by reducing water saturation of the fracture and selective dissolution of the fracture surface. Since the fracturing flowback fluid faces a serious risk of environmental pollution and purification treatment due to its variety and complexity of pollutants, oxidative stimulation can prevent environmental pollution by reducing the leakage risk of the flowback fluid with a low flowback rate and continuous purification treatment of the flowback fluid, thus achieving the goal of environmentally friendly development and stimulation of shale gas reservoirs.

show abstract

Experimental study of the fracture initiation through the synergy of spontaneous imbibition and hydration of residual fracturing fluids in shale gas reservoirs

Cited by 13 publications

References 34 publications

Using Spontaneous Imbibition to Evaluate the Hydrocarbon Migration and Accumulation Potential of Shale Reservoirs: A Case Study of the Permian Fengcheng Formation in the Mahu Sag, Junggar Basin

Using Spontaneous Imbibition to Evaluate the Hydrocarbon Migration and Accumulation Potential of Shale Reservoirs: A Case Study of the Permian Fengcheng Formation in the Mahu Sag, Junggar Basin

Hydraulic Fracturing and Enhanced Recovery in Shale Reservoirs: Theoretical Analysis to Engineering Applications

Study on Formation Damage of Fracturing and Its Prevention through an Environmentally Friendly Method of Oxidative Stimulation in Shale Gas Reservoirs

Contact Info

Product

Resources

About