Patent ID: 11873712
Assignee: CHINA UNIVERSITY OF PETROLEUM—BEIJING
Field: Measurement (Instruments)
Classification: CPC E  G | IPC E  G

Claim 0:
1. An edge and bottom water invasion simulation apparatus, wherein the apparatus comprises a first intermediate container, a core holder, a back pressure valve, and a controller, wherein a first piston is disposed in the first intermediate container, and the first piston is configured to separate formation water and an inert gas; a liquid outlet end of the first intermediate container is connected to an inlet end of the core holder, and an outlet end of the core holder is connected to the back pressure valve; the controller is connected to the first intermediate container, the core holder, and the back pressure valve, respectively;
the controller is configured to control the inert gas to be injected into the first intermediate container through a gas inlet end of the first intermediate container, and to stop the inert gas from being injected into the first intermediate container when an internal pressure of the first intermediate container reaches an initial gas pressure;
the controller is configured to control the formation water to be injected into the first intermediate container through a liquid inlet end of the first intermediate container, and to stop the formation water from being injected into the first intermediate container when the internal pressure of the first intermediate container reaches an initial formation pressure;
the controller is configured to control the liquid outlet end of the first intermediate container to be communicated with the inlet end of the core holder;
the controller is configured to adjust a pressure of the back pressure valve to reduce a pressure at the outlet end of the core holder, so that the formation water in the first intermediate container enters a core in the core holder through the liquid outlet end of the first intermediate container and the inlet end of the core holder sequentially, so as to simulate an edge and bottom water invasion;
wherein the apparatus further comprises a second intermediate container, a displacement pump, and a recovery device, a second piston is disposed in the second intermediate container, and the second piston is configured to separate an inert gas and a liquid; the second intermediate container is connected to the displacement pump, a gas outlet end of the second intermediate container is connected to the outlet end of the core holder, and the outlet end of the core holder is connected to the recovery device; the controller is connected to the second intermediate container, the displacement pump, and the recovery device, respectively;
the controller is further configured to control the outlet end of the core holder to be disconnected from the recovery device when the outlet end of the core holder is subjected to a first water breakthrough;
the controller is further configured to set a corresponding pressure value of the displacement pump to the initial formation pressure, so that the liquid enters the second intermediate container from a liquid inlet end of the second intermediate container to compress the inert gas in the second intermediate container, so as to make an internal pressure of the second intermediate container reach the initial formation pressure;
the controller is further configured to, when the internal pressure of the second intermediate container reaches the initial formation pressure, control the outlet end of the core holder to be communicated with the gas outlet end of the second intermediate container, so that the inert gas in the second intermediate container enters the core holder through the gas outlet end of the second intermediate container and the outlet end of the core holder sequentially;
the controller is further configured to determine an injection volume of the inert gas entering the core holder according to a liquid injection volume when an internal pressure of the core holder reaches the initial formation pressure;
the controller is further configured to, when the internal pressure of the core holder reaches the initial formation pressure, control the outlet end of the core holder to be communicated with the recovery device, and adjust the pressure of the back pressure valve to reduce the pressure at the outlet end of the core holder, so that a gas inside the core holder flows from the outlet end of the core holder into the recovery device;
the controller is further configured to, when the outlet end of the core holder is subjected to a second water breakthrough, control the outlet end of the core holder to be disconnected from the recovery device, and analyze the gas recovered by the recovery device to determine a recovery volume of natural gas, and determine a recovery of the natural gas during the second water breakthrough according to the recovery volume of the natural gas and a total volume of the natural gas in the core saturated with the natural gas.