3results about How to "Improve displacement efficiency" patented technology

The invention discloses a carbon dioxide inter-section displacement pre-fracturing process and a design method and related equipment thereof, and belongs to the technical field of oil and gas production, the design method comprises the following steps: establishing an integrated fractured horizontal well numerical simulation model according to seismic data of a target well, logging interpretation data and an engineering parameter range given by an oil production scheme; the integrated fractured horizontal well numerical simulation model is used for simulating single well yields under different section intervals and different single-section carbon dioxide injection amounts by adopting a section-separated gas injection method; drawing a parameter optimization chart based on the single well yield and the carbon dioxide injection section number obtained under different section distances and different single-section carbon dioxide injection amounts; and according to the parameter optimization plate, determining the final segment spacing and the single-segment carbon dioxide injection amount. While the recovery efficiency is improved, the construction efficiency is improved, and the fracturing cost is saved.

The application discloses a thick coal seam gas extraction method applying directional multi-branch long borehole gas drive flow increasing, which comprises the following steps: A: coal seam geological condition investigation; B: completing the construction of the bedding extraction borehole and the directional multi-branch long borehole, and pre-extracting under negative pressure before mining; C: selecting a directional multi-branch long borehole as a first gas injection borehole, and implementing a long injection short extraction mode; D: after the first gas injection borehole gas injection is completed, a long extraction short extraction mode is implemented; then a second gas injection borehole is selected to implement the long injection short extraction mode; E: a third, a fourth, and so on, gas injection borehole is selected to implement the long injection short extraction mode according to the method in the step D; the first round of gas extraction is completed; F: according to the method in the step E, the second round, the third round, and so on, of gas extraction is continuously completed until the gas in the thick coal seam is fully extracted through the gas drive flow increasing mode. The application can effectively solve the problem of low gas extraction efficiency of the upper horizon of the existing thick coal seam.

This application provides a method and system for dynamic coalbed methane injection with proportional path control. The system includes a parameter input module for acquiring basic coal seam parameters; a control module for determining a target proportional change model based on these parameters, thereby determining a first volume fraction of nitrogen and a second volume fraction of carbon dioxide in the total injection volume; and a valve control signal for determining the first and second volume fractions. A gas supply module is used to adjust the valve openings of the nitrogen and carbon dioxide supply devices based on the valve control signal. The control module also determines the equivalent permeability of the coal seam based on the coal seam parameters, and determines the gas injection stage based on this permeability. According to the gas injection stage, a corresponding gas injection strategy is executed through the staged injection module. This scheme achieves continuous adjustment of the nitrogen-to-carbon dioxide ratio, thereby improving gas propulsion stability and coalbed methane displacement efficiency.