A monitoring method for fluidized gas drainage

Abstract

A monitoring method for fluidized gas drainage is suitable for underground use in coal mines. First, horizontal drilling, monitoring drilling and gas drainage drilling are drilled into deep low-permeability coal seams, using liquid CO 2 The phase change fracturing technology breaks the coal body; then the multi-functional assembly device is sent to the design position of the horizontal drilling along with the bendable copper pipe. The container of the detector is sent into the monitoring drilling well, and the smoldering degree and regional scope of the coal body can be calculated by real-time monitoring of the real-time temperature, gas concentration and pressure, and the content and change of SF6 gas in the horizontal drilling range; comprehensive coal body temperature and generation The change of gas concentration of the gas is evaluated according to the relevant drainage parameters to evaluate the gas drainage efficiency. The system has accurate monitoring and convenient application, which can greatly improve the monitoring efficiency of gas drainage.

Description

technical field [0001] The invention relates to a monitoring method for fluidized gas drainage, in particular to an instant monitoring and evaluation of coal seam smoldering parameters and gas drainage in the gas fluidized mining process of deep low-permeability coal seams. Background technique [0002] Aiming at the problem of low gas drainage efficiency in deep low-permeability coal seams, the main strengthening measures at home and abroad include hydraulic fracturing technology, thermal drive technology, blasting technology, etc. These methods mainly destroy the coal body structure through external media, forming a series of multiple The distribution of scale fractures provides a certain seepage channel for gas flow. Field and physical experiments have proved that these methods can effectively improve the permeability of coal seams and promote the efficiency of coal bed methane extraction. [0003] However, these technologies have certain deficiencies in field application...

AI Technical Summary

Problems solved by technology

[0003] However, these technologies have certain deficiencies in field application and real-time monitoring

For example, hydraulic fracturing technology essentially requires a large amount of water resources, which cannot meet the needs of gas drainage in coal seams in water-deficient areas. At the same time, coal seams contain certain clay components and low wettability, which may easily cause reservoir damage and The emergence of the water lock effect has a certain impact on the real-time and accuracy of coal seam fracturing and gas drainage index monitoring; thermal drive technology needs to use a large amount of thermal energy to break the coal body, and it is difficult to crack large-scale coal bodies. In addition, the small thermal conductivity of the coal body often limits the range of thermal drive and the range of coal crushing. In addition, the requirements for high temperature resistance and anti-interference of thermal drive technology monitoring equipment are more stringent, and the sensitivity of existing equipment Poor; blasting technology is prone to problems such as difficulty in feeding powder and dumb shots, and repeated operations are difficult, and its instantaneous action is likely to cause stress disturbance in the formation, which seriously affects the real-time accuracy of monitoring equipment

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