Analysis of Characteristics and Feasibility of High-pressure- and Low-temperature Water Jet Method of Exploiting Marine Natural Gas Hydrate

Abstract Natural gas hydrate is a research hotspot at present. However, the current exploitation technology can’t meet the demand of commercial exploitation of natural gas hydrate. In order to improve the efficiency of hydrate production, this paper believes that the idea of using high-pressure water jets for sandblasting perforation is expected to constitute an effective way to extract natural gas hydrates. The experimental study on sandblasting perforation and hydraulic slitting of simulated reservoirs was carried out by using large-scale ground fracturing equipment and full-scale hydraulic blasting perforating equipment. The driving pressure is analysed under the action of high-pressure water jet. The influence of diameter on the effect of simulated reservoir fracture. The results show that the diameter of the perforation increases with the increase of pressure; This experimental study can provide an experimental basis for the use of abrasive jet blasting perforating technology to improve the efficiency of natural gas hydrate production.

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Natural gas exploitation by carbon dioxide from gas hydrate fields—high-pressure phase equilibrium for an ethane hydrate system

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1243/0957650981536826 ◽

1998 ◽

Vol 212 (3) ◽

pp. 159-163 ◽

Cited By ~ 25

Author(s):

S Nakano ◽

K Yamamoto ◽

K Ohgaki

Keyword(s):

High Pressure ◽

Phase Equilibrium ◽

Natural Gas ◽

Gas Hydrate ◽

Phase Behaviour ◽

High Pressure Phase ◽

Natural Gas Hydrate ◽

Public Attention ◽

Hydrate Water ◽

Pressure Phase

Natural gas hydrate fields, which have a large amount of methane and ethane deposits in the subterranean Arctic and in the bottom of the sea at various places in the world, have become the object of public attention as a potential natural gas resource. Here the idea of natural gas exploitation from natural gas hydrate fields combined with CO2 isolation using CO2 hydrate has been presented. As a fundamental study, high-pressure phase behaviour for the ethane hydrate system was investigated in a high-pressure cell up to a maximum pressure of 100 MPa, following a previous study of CO2 and methane hydrates. Consequently, the phase equilibrium relationship of an ethane hydrate—water—liquid ethane mixture was obtained in the temperature range from 290.4 to 298.4 K and over a pressure range of 19.48 to 83.75 MPa. The observed phase boundary corresponds to the three-phase coexisting line with a non-variant quadruple point of ethane hydrate—water—liquid ethane—gaseous ethane at 288.8 K and 3.50 MPa, similar to the CO2 hydrate—water—liquid CO2 system.

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Research on Prediction Methods of Wellbore Hydrate Formation of Ultra-Deep Gas Wells in Northwest Sichuan

E3S Web of Conferences ◽

10.1051/e3sconf/202132901076 ◽

2021 ◽

Vol 329 ◽

pp. 01076

Author(s):

Qilin Liu ◽

Jian Yang ◽

Lang Du ◽

Jianxun Jiang ◽

Dan Ni ◽

...

Keyword(s):

High Pressure ◽

High Temperature ◽

Natural Gas ◽

Gas Hydrate ◽

Hydrate Formation ◽

Natural Gas Hydrate ◽

Gas Wells ◽

Prediction And Control ◽

Sulfur Containing ◽

High Temperature High Pressure

According to the formation and handling situation of hydrate in ultra-deep high-pressure sulfurcontaining gas wells in northwest Sichuan, the formation conditions of natural gas hydrate was studied based on previous studies on hydrate, the molecular dynamics of natural gas hydrate and the multiphase flow law of high-temperature high-pressure high-sulfur-containing gas wellbore were combined, and the pressure prediction model with high-temperature high-pressure sulfur-containing gas wells as the target was built. The chemical and physical control methods of wellbore hydrate plugging were discussed to provide the scientific theoretical basis for the prediction and control of hydrate in high-temperature high-pressure high-sulfurcontaining gas wells.

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Visualization and investigation of the erosion process for natural gas hydrate using water jet through experiments and simulation

Energy Reports ◽

10.1016/j.egyr.2021.11.235 ◽

2022 ◽

Vol 8 ◽

pp. 202-216

Author(s):

Yiqun Zhang ◽

Xiaoya Wu ◽

Xiao Hu ◽

Bo Zhang ◽

Jingsheng Lu ◽

...

Keyword(s):

Natural Gas ◽

Gas Hydrate ◽

Water Jet ◽

Erosion Process ◽

Natural Gas Hydrate

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Experimental and Theoretical Study on the Critical Breaking Velocity of Marine Natural Gas Hydrate Sediments Breaking by Water Jet

Energies ◽

10.3390/en13071725 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1725

Author(s):

Leizhen Wang ◽

Guorong Wang

Keyword(s):

Natural Gas ◽

Critical Velocity ◽

Gas Hydrate ◽

Orthogonal Design ◽

Water Jet ◽

Frozen Soil ◽

Nozzle Diameter ◽

Design Experiment ◽

Natural Gas Hydrate ◽

Undetermined Coefficient

Water jet technology is a key technology in the marine natural gas hydrate (NGH) solid fluidization mining method. As an important parameter in water jet breaking NGH sediments technology, the critical breaking velocity of NGH sediments is unknown. In the present research, an orthogonal design experiment is carried out to study the critical velocity of NGH breakage by water jet, using frozen soil and sand as experimental samples. First, the time it takes to reach maximum NGH breaking depth is determined. Then, ultimate breaking distance is studied with respect to the NGH saturation, jet pressure, and nozzle diameter. Following that, the variation of critical velocity with NGH saturation is analyzed. Eventually, a formula to calculate the critical velocity for marine NGH breakage by water jet process is established, and the undetermined coefficient (η) in the formula is calibrated with the experiment data. The results show that the ultimate breaking distance is mostly achieved within 63 s. The three experimental factors in order of the effect on the ultimate breaking depth (from high to low) are NGH saturation, jet pressure, and nozzle diameter. The critical velocities for marine NGH breakage corresponding to the NGH saturations of 20%, 40,%, 6%, and 80% are 5.71 m/s, 7.14 m/s, 9.60 m/s, and 10.85 m/s, respectively. The undetermined coefficient η in critical velocity formula is 1.44 m/s.

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