Evaluation of the gas production enhancement effect of hydraulic fracturing on combining depressurization with thermal stimulation from challenging ocean hydrate reservoirs

Zhong, Xiuping; Pan, Dong; Zhai, Lianghao; Zhu, Ying; Zhang, Han; Zhang, Ying; Li, Xitong; Chen, Chen

doi:10.1016/j.jngse.2020.103621

Cited by 54 publications

(30 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on this, considering the influence of gravity and capillary force, the two-phase flow in the rock matrix and fractures can be given . The fracture setting was based on our previous research, the fracture permeability was set to 2D, and the fracture width was set to 6 mm . A total of 7311 grids were constructed.…”

Section: Numerical Model and Simulation Schemementioning

confidence: 99%

“…Recently, hydraulic fracturing became a hot topic in hydrate development stimulation. Many studies have determined the fracability of hydrate-bearing sediments , and investigated the stimulation potential of hydraulic fracturing on hydrate development. − Our previous studies have explored the stimulation effect of hydraulic fracturing on the development mode of D + T iw and investigated the influence of fracture parameters on the exploitation effect. , Studies’ results determined that the fractures can greatly promote hydrate decomposition, and especially, the fractures greatly promote the migration of CH 4 released by the thermal stimulation to the production wells. As a result, the depressurization combined with hot water injection stimulated by hydraulic fracturing (D + T iw + HF) development mode show an excellent CH 4 production capacity, indicating that D + T iw + HF has a promising application prospect.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Research on the Influence of Injection–Production Parameters on Challenging Natural Gas Hydrate Exploitation Using Depressurization Combined with Thermal Injection Stimulated by Hydraulic Fracturing

et al. 2021

Self Cite

View full text Add to dashboard Cite

The development of low-permeability hydrate reservoirs is facing serious problems. Our previous studies determined that depressurization combined with hot water injection stimulated by hydraulic fracturing (D + Tiw + HF) development mode has an excellent production potential in low-permeability hydrate reservoirs. Based on these, this study further explored the influences of injection–production parameters including injection temperature (T i), injection pressure (P i), and production pressure (P p) on D + Tiw + HF through single-factor and multivariate sensitivity analysis. Results show that the influence of T i, P i, and P p on D + Tiw + HF was divided into two opposite stages by the water breakthrough of production wells (t wb). The hydrate decomposition rate and CH4 production rate increase linearly with the increase in T i and P i and decrease in P p before t wb; however, they decrease gradually with the increase in T i and P i and decrease in P p after t wb. The sensitivity ranges of cumulative CH4 production (V P) to P p, T i, and P i are (3, 4.5), (0, 1.5), and (0, 1) in the first year and (1, 5), (0.5, 3), and (1, 2) in the fifth year, respectively. The sensitivity ranges of the energy ratio (ER) to P p, T i, and P i are (−2, −1), (−6, 0), and (−2.5, −1.5) in the first year and (−1.5, −1), (−7, 0), and (−2, 1) in the fifth year, respectively. This determines that V P is most sensitive to Pp , and the ER is most sensitive to T i. Furthermore, the ER is more sensitive to smaller T i. The V P is more sensitive to smaller P p in the early development stage (1 year, before t wb), while it is more sensitive to lager P p in the later development stage (5 years, after t wb). As a result, an as low as possible P p, low T i, and higher P i is suggested in the early development stage, while low T i and higher P i are suggested in the later development stage, and too small P p is unnecessary.

show abstract

Section: Numerical Model and Simulation Schemementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Research on the Influence of Injection–Production Parameters on Challenging Natural Gas Hydrate Exploitation Using Depressurization Combined with Thermal Injection Stimulated by Hydraulic Fracturing

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Sun et al 22 evaluated the gas production performance of a silty hydrate reservoir at site SH2 in the South China Sea with a horizontal well by hydraulic fracturing and claimed that this method could substantially decrease the number of operation wells and improve the economic efficiency. Zhong et al 37 also studied the hydrate reservoir at site SH2 and investigated the influence of hydraulic fracturing combined with depressurization and thermal stimulation via a three-spot parallel horizontal-well system. They found that hydraulic fracturing had a significant promoting effect on the gas recovery and energy ratios.…”

Section: Introductionmentioning

confidence: 99%

Gas Production Enhancement from a Multilayered Hydrate Reservoir in the South China Sea by Hydraulic Fracturing

Guan

Wang

et al. 2021

Energy Fuels

View full text Add to dashboard Cite

In this work, hydraulic fracturing was used for gas hydrate production at the second test site in the South China Sea for the first time. A multilayered hydrate reservoir model with low permeabilities was built on the basis of the field data obtained at this site, and artificial fractures were assumed to be created in the hydrate-bearing layer by hydraulic fracturing. Long-term simulations of the depressurization-induced gas hydrate production were conducted with a horizontal well, and the effects of the fractures on the enhanced gas recovery were thoroughly investigated. From the analysis of the simulation results, it can be known that the horizontal fracture could greatly promote the long-term production of natural gas from the reservoir, while the vertical branch fractures mainly contributed to the short-term gas recovery. By a combination of a horizontal fracture of 50 m with four branch fractures of 40 m, the long-term average gas production rate for a 1000 m long horizontal well was estimated to be 1.49 × 104 m3/day, and thus only two such horizontal wells were required to reach the level of the second Shenhu field trial (2.87 × 104 m3/day). This indicated that hydraulic fracturing was a promising technology for gas production enhancement from low-permeability clayey-silt hydrate reservoirs.

show abstract

“…Among them, hydraulic fracturing is not only used for testing seismic sources [12,13] but also has been widely used in the development and exploitation of low-permeability oil and gas fields as a major measure to increase production in oil and gas wells. Zhong et al [14] proposed that the stimulation of hydraulic fracturing on a combination of depressurization with thermal stimulation for natural gas hydrate (NGH) exploitation from challenging ocean hydrate reservoirs is investigated in this study. The influence of fracture permeability, well spacing on hydrate exploitation, and the enhancement effect of hydraulic fracturing on different well spacings is numerically investigated.…”

Section: Introductionmentioning

confidence: 99%

Study on the Damage Model of Coal Rock Caused by Hydraulic Pressure and Electrical Impulse in Borehole

et al. 2021

View full text Add to dashboard Cite

The purpose of this study is to study the damage and fracturing effects of high-voltage discharge on coal-rock mass under the action of hydrostatic pressure. Based on the traditional damage evolution model and the change of the effective bearing area and stress around the microcrack of coal-rock mass on a microscopic scale, the expression of macroscopic damage variation of coal-rock mass under the action of electrohydraulic coupling was derived, and its damage constitutive relation was established. The high-voltage pulse water shock stress test of coal-rock mass under the conditions of different water pressures and voltages was carried out, and its damage numerical model was established by the ABAQUS/XFEM. The damage variable values of coal-rock mass with different electrohydraulic parameters were compared to characterize the generation and expansion of internal macroscopic cracks. From the results, it is shown that the damage variable based on the effective bearing area and stress around the crack can represent the morphology and expansion change of crack of coal-rock mass with different electrohydraulic parameters clearly and quantitatively. Different hydrostatic pressures and discharge voltages have influence on the damage variables of coal-rock mass, but different influencing degrees cause different damages on coal-rock mass. The damage of coal rock can be characterized by the change of the effective bearing area and stress around microcracks in coal body. So, stress testing and numerical simulation have verified the correctness of the damage model.

show abstract

Evaluation of the gas production enhancement effect of hydraulic fracturing on combining depressurization with thermal stimulation from challenging ocean hydrate reservoirs

Cited by 54 publications

References 37 publications

Research on the Influence of Injection–Production Parameters on Challenging Natural Gas Hydrate Exploitation Using Depressurization Combined with Thermal Injection Stimulated by Hydraulic Fracturing

Research on the Influence of Injection–Production Parameters on Challenging Natural Gas Hydrate Exploitation Using Depressurization Combined with Thermal Injection Stimulated by Hydraulic Fracturing

Gas Production Enhancement from a Multilayered Hydrate Reservoir in the South China Sea by Hydraulic Fracturing

Study on the Damage Model of Coal Rock Caused by Hydraulic Pressure and Electrical Impulse in Borehole

Contact Info

Product

Resources

About