Patents by Inventor Yunkai Ji

Yunkai Ji has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10969514
    Abstract: The application relates to the technical field of oil and gas field development, and discloses a correction method and system for a permeability model considering gas hydrate distribution, and a method and system for determining the permeability of the hydrate-bearing porous medium.
    Type: Grant
    Filed: September 9, 2020
    Date of Patent: April 6, 2021
    Assignee: CHINA UNIVERSITY OF PETROLEUM (EAST CHINA)
    Inventors: Jian Hou, Yunkai Ji, Qingjun Du, Yongge Liu, Kang Zhou, Yueliang Liu, Bei Wei, Ermeng Zhao, Nu Lu, Yajie Bai
  • Patent number: 10830019
    Abstract: A method for improving the gas recovery of a natural gas hydrate reservoir by using artificial impermeable layers is described. Artificial impermeable layers are formed by injecting cement slurry into the permeable overburden and underburden layers. When depressurization exploitation is performed, a large amount of seawater can be effectively blocked from entering a hydrate layer, and a production pressure difference between the hydrate layer and the production well is effectively increased, so that a hydrate decomposition rate and the gas recovery are improved.
    Type: Grant
    Filed: October 14, 2019
    Date of Patent: November 10, 2020
    Assignee: CHINA UNIVERSITY OF PETROLEUM (EAST CHINA)
    Inventors: Jian Hou, Ermeng Zhao, Yongge Liu, Kang Zhou, Bei Wei, Yunkai Ji, Nu Lu, Yajie Bai, Wenbin Liu
  • Patent number: 10815778
    Abstract: The disclosure discloses a method for obtaining formation parameters of a gas hydrate reservoir through well testing interpretation, which comprises: (1) establishing a physical model for well testing interpretation of the gas hydrate reservoir according to multiphase flow, hydrate dissociation, secondary hydrate formation and heat transfer exhibited in the well testing process of the gas hydrate reservoir; (2) establishing a mathematical model for well testing interpretation of the gas hydrate reservoir; (3) conducting spatial discretization and temporal discretization on the mathematical model, and adopting a finite volume method to obtain a numerical solution of bottom-hole pressure; (4) calculating a bottom-hole pressure variation curve and a production rate variation curve in the well testing process of the hydrate reservoir, and drawing theoretical curves of bottom-hole pressure difference and pressure difference derivative; and (5) matching a measured pressure curve with the theoretical curve to obtain
    Type: Grant
    Filed: December 2, 2019
    Date of Patent: October 27, 2020
    Assignee: CHINA UNIVERSITY OF PETROLEUM (EAST CHINA)
    Inventors: Jian Hou, Ermeng Zhao, Yongge Liu, Yueliang Liu, Bei Wei, Yunkai Ji, Yajie Bai, Nu Lu, Huiyu Wang
  • Patent number: 10816531
    Abstract: A daily gas production rate of a methane hydrate deposit is calculated based on inflow performance relationship formulas. Step 1 determines the production stage, including the gas production rate trend of a production test and selecting an inflow performance relationship formula corresponding to the stage. Step 2 calculates basic coefficient terms related to energy conversion in the inflow performance relationship formula. Step 3 obtains other coefficient terms related to production in the inflow performance relationship formula. Step 4 predicts the gas production rate under other production pressure differences. Staged inflow performance relationship formulas characterize the complex methane hydrate deposit production performance.
    Type: Grant
    Filed: May 27, 2020
    Date of Patent: October 27, 2020
    Assignee: China University of Petroleum (East China)
    Inventors: Jian Hou, Nu Lu, Yongge Liu, Yajie Bai, Yunkai Ji, Ermeng Zhao
  • Patent number: 10344576
    Abstract: The example of implementation of the invention provides a method used for exploiting a natural gas hydrate reservoir and belongs to the field of natural gas hydrate reservoir exploitation. The method mainly comprises a heat-injecting vertical well and a production horizontal well. The production horizontal well is opened in a segmental manner. In combination with natural gas hydrate heat exploitation, heat flow injected into the vertical well is enabled to heat different positions of the natural gas hydrate reservoir to increase a recovery ratio of the natural gas hydrate reservoir. The method specifically comprises the steps of injecting a heat flow into the natural gas hydrate reservoir by utilizing the vertical well to promote decomposition of the hydrate; firstly opening a horizontal branch of the horizontal well fully and keeping depressurization exploitation.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: July 9, 2019
    Assignee: CHINA UNIVERSITY OF PETROLEUM (EAST CHINA)
    Inventors: Jian Hou, Yongge Liu, Kang Zhou, Qingjun Du, Yajie Bai, Yunkai Ji, Nu Lu, Wenbin Wang