Tracer diffusion device, system for tracing development of water conducting fracture zone and relataed method

A system for tracing a development of a water conducting fracture zone, comprising:

• a tracer diffusion device;
• a coal seam;
• wherein the coal seam comprises a goaf;
• a plurality of aquifers above the coal seam;
• a borehole, drilled from above the goaf downward through the plurality of aquifers;
• a collection device, connected to the goaf for collecting fluids within the goaf;
• and
• a monitoring device, located near the collection device, for monitoring the tracer in the fluids;
• wherein,
• the tracer diffusion device comprises:
• a first container, for holding a first fluid containing a tracer;
• a second container, for holding a second fluid;
• a drilling pipe;
• wherein a first end of the drilling pipe is connected to the first container;
• a second end of the drilling pipe is extended into a borehole drilled through a plurality of aquifers above the goaf;
• and the second end of the drilling pipe is equipped with a first sealing capsule and a second sealing capsule;
• the first sealing capsule is used to seal a first space above a target aquifer among the plurality of aquifers;
• the second sealing capsule is used to seal a second space below the target aquifer;
• the first sealing capsule is connected to the second container;
• a plurality of through holes are arranged on the drilling pipe between the first sealing capsule and the second sealing capsule;
• a unidirectional driving device, arranged on the drilling pipe, for injecting the first fluid from the first container into the borehole between the first sealing capsule and the second sealing capsule to diffuse the tracer into the target aquifer;
• and
• a bidirectional driving device, arranged between the second container and the first sealing capsule, for injecting the second fluid from the second container into the first sealing capsule and the second sealing capsule to make the first sealing capsule and the second sealing capsule expand to block the borehole;
• or, for extracting the second fluid from the first sealing capsule and the second sealing capsule back into the second container to make the first sealing capsule and the second sealing capsule to contract.