Coal spontaneous combustion downhole detection system and method based on self-potential method

1 . A coal spontaneous combustion downhole detection system based on a self-potential method, comprising a self-potential detection apparatus and a self-potential processing apparatus,

wherein the self-potential detection apparatus comprises measuring electrodes, a reference electrode and metal anchor rods; the measuring electrodes are arranged on a top plate of a goaf roadway, are fixed to the metal anchor rods, and are in wireless connection with the reference electrode through the metal anchor rods;

the self-potential processing apparatus comprises a data processing sensor and an imaging sensor; and the measuring electrodes and the reference electrode are in wireless connection with the data processing sensor;

wherein the measuring electrodes are arranged in electrode baths and are fixed by the metal anchor rods; one measuring electrode is arranged in each electrode bath; the electrode baths are arranged on the top plate of a goaf roadway; and the spacing between every two adjacent electrode baths is 10 m.

2 . The coal spontaneous combustion downhole detection system based on a self-potential method according to claim 1 ,

the measuring electrodes are in wireless connection with the reference electrode through low pass filters, data acquisition cards and the metal anchor rods for signal transmission; and the measuring electrodes, the low pass filters, the data acquisition cards and the metal anchor rods are in one-to-one correspondence.

3 . The coal spontaneous combustion downhole detection system based on a self-potential method according to claim 1 ,

the measuring electrodes and reference electrode are non-polarizing copper sulfate electrodes and are made of magnetic rods.

4 . A coal spontaneous combustion downhole detection method based on a self-potential method, comprising the following steps:

S1, digging a plurality of electrode baths in the top plate area of the goaf roadway according to the roadway length;

S2, welding the measuring electrodes to the metal anchor rods, and then connecting and protecting the measuring electrodes, the low pass filter and the data acquisition card sequentially;

S3, burying the measuring electrodes into the electrode baths of the top plate through fixing the measuring electrodes with the metal anchor rods, and transmitting signals wirelessly;

S4, enabling the self-potential processing apparatus to give a command to each data acquisition card to collect the information of each measuring electrode, and storing the information in the data acquisition card temporarily; and

S5, utilizing the characteristic that the metal anchor rods can enhance signal transmission to transmit the information in the data acquisition card to a data processing sensor in the self-potential processing apparatus, enabling the data processing sensor to process the information according to the collecting time, the serial number of the measuring electrodes, the size of the self-potential signal, and the relationship between the self-potential signal and temperature, and transmitting the processed data to an imaging sensor to convert the data into images.

5 . The coal spontaneous combustion downhole detection method based on a self-potential method according to claim 4 , wherein in S2, the metal anchor rods are copper anchor rods to enhance the signal.

6 . The coal spontaneous combustion downhole detection method based on a self-potential method according to claim 4 , wherein the spacing T between every two adjacent electrode baths is 10 m.