A method for judging the three-dimensional spontaneous combustion dangerous area in multi-layer goaf of coal seam group

Abstract

The invention provides a judgment method for a three-dimensional spontaneous combustion dangerous region of a multilayered goaf of a coal seam group, belongs to the field of prevention and control ofcoal spontaneous combustion fire. The method comprises the following steps: collecting a coal sample of each coal seam; determining critical oxygen concentrations of primary oxidization of the coal sample of a lower coal seam and secondary oxidization of the coal sample of an upper coal seam respectively through a programmed temperature-rising oxidization experiment; taking a height position of residual coal of the goaf as an evidence and dividing the multilayered goaf formed by mining the coal seam group into an upper position, a middle position and a lower position; combining high-position drilling and beam tube monitoring to realize simultaneous monitoring of gas parameters of the goaf at the upper position, the middle position and the lower position; determining a three-dimensional spontaneous combustion dangerous region distribution range of the goaf at the upper position, the middle position and the lower position of the coal seam group through critical oxygen concentration indexes obtained by the experiment and on-site comprehensive actually-measured parameters. According to the method provided by the invention, the division of the multilayered goaf of the coal seam group ismore comprehensive and reasonable; a coal spontaneous combustion danger judgment index is more precise and accurate; the method has high practicability and operability, and important guiding significance on targeted and effective prevention and control of spontaneous combustion fire disasters of the coal seam group.

Description

technical field [0001] The invention belongs to the technical field of coal spontaneous combustion fire prevention and particularly relates to a method for judging a three-dimensional spontaneous combustion dangerous area in a multi-layer goaf of a coal seam group. Background technique [0002] In the process of coal seam mining, the roof stratum collapses to form a goaf, and due to the influence of coal and rock occurrence conditions, mining technology and other factors, there is often a certain thickness of coal left in the goaf. Under the condition of air leakage and oxygen supply, the leftover Coal is prone to spontaneous combustion. The determination of the spontaneous combustion risk area of ​​coal remaining in the goaf in the traditional single coal seam mining is generally to monitor the oxygen concentration, temperature and other factors in the gob by laying beam tubes, and to determine the spontaneous combustion risk area with the industry-recognized division index...

AI Technical Summary

Problems solved by technology

At this time, the oxidative spontaneous combustion characteristics of the residual coal in the upper gob area are partially changed compared with the primary oxidized residual coal, and the judgment index of the spontaneous combustion dangerous area using the primary oxidized residual coal has a certain error

At the same time, the existing methods for judging spontaneous combustion risk areas focus on the division of spontaneous combustion risk areas in single coal seam goafs, without analyzing the distribution of spontaneous combustion risk areas from the three-dimensional perspective of multi-layer gobs in coal seam groups, and the oxygen concentration, temperature and other parameters are tested. The method is difficult to apply to the three-dimensional space conditions of multi-layer gobs, and the technical limitations are very obvious

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