Infrasound detection device and method of determining goaf fire area of coal field

Abstract

The invention relates to an infrasound detection device and method of determining a goaf fire area in a coal field. The device includes an underground semi-space infrasound collecting and amplifying component / assembly, an infrasonic sensor, a preamplifier, a low-pass filter, a data recorder, a computer and a data transmission line. According to the infrasound detection device and method of the invention, ground semi-space signals are shielded through an internally-vacuumized double-layer hemispheric device; underground semi-space infrasound signals are received through the infrasonic sensor connected with the underground semi-space infrasound collecting and amplifying component / assembly; the output signals of the infrasonic sensor are transmitted to the preamplifier through the data transmission line; after being processed by the preamplifier, the signals are transmitted to the low-pass filter through the data transmission line, so that audio signals of which the frequency is higher than 20Hz are filtered out; the filtered signals are transmitted to the data recorder; data in the data recorder are inputted into the computer; and based on software calculation and analysis, the combustion fire area of the coal field can be located. The infrasound detection device has the advantages of simple structure, convenient operation and high detection accuracy.

Description

Technical field [0001] The invention relates to an infrasound detection and delineation device and method for a coal field goaf fire area, belonging to the field of coal field fire area safety, and is especially suitable for detecting and delimiting a coal goaf fire area. Background technique [0002] There are a large number of coal field fire areas in my country's Xinjiang, Inner Mongolia, Shanxi, Ningxia, Gansu, Qinghai and other provinces (autonomous regions). The existence of a large number of coal field fires not only directly burned non-renewable coal resources, but also indirectly caused dozens of times of stagnant resources to be unexploited, and directly threatened the safety of coal mine production and the local ecological environment and groundwater resources. According to incomplete statistics, our country loses 10 million tons of coal every year due to coal fires, and economic losses exceed 20 billion. In order to achieve efficient management of coal fires and redu...

AI Technical Summary

Problems solved by technology

The borehole temperature measurement method uses thermocouples, infrared thermometers and other temperature measuring instruments to test the temperature in the borehole after drilling in the fire area, and judges the distribution and development degree of the fire area according to the temperature of the borehole; this method It is the most direct method, but due to the poor thermal conductivity of coal and rock, in order to achieve a more accurate detection of the fire area, it is necessary to intensively drill holes in the entire detection area (generally, the hole spacing is less than 10m), and the workload is large and the cost is high. High; the magnetic method delineates the boundary of the fire area by detecting the thermal remanence generated by the burnt rock in the fire area, but the burnt rock can generally produce significant thermal remanence only when the temperature is higher than 400 °C. For the area below 400 °C due to its The generated thermal remanence is low, resulting in poor detection accuracy; therefore, this method cannot meet the detection requirements in areas below 400°C

The radon measurement method judges the distribution of coalfield fire areas through the detection of radon elements in the detection area. It is believed that the greater the concentration of radon elements, the more serious the development of fire areas. However, the gas measurement method is also limited by factors such as the thickness of the fire zone and the degree of fracture development, which is similar to the radon measurement method. ; The remote sensing method is suitable for the detection of fire areas with obvious temperature anomalies on the surface, but not suitable for the detection of fire areas where the surface temperature is not obvious

Images