Coupling Test System for Three-Dimensional Gas Extraction and Spontaneous Combustion in Goaf

Patterns of Spontaneous Combustion in Goaf under Different Gas Extraction Conditions

I. Equipment Introduction:

The Coupling Test System for Three-Dimensional Gas Extraction and Spontaneous Combustion in Goaf is an earth exploration instrument used in the fields of engineering and technological science, mining engineering technology, civil construction engineering, and transportation engineering.

The main system includes: 1) Goaf simulation subsystem; 2) Three-dimensional gas extraction subsystem; 3) Ventilation subsystem; 4) Temperature control subsystem; 5) Temperature measurement subsystem; 6) Gas pressure measurement subsystem; 7) Gas concentration testing subsystem; 8) Stress measurement subsystem, among others. This system can simulate the patterns of spontaneous combustion in goaf under different gas extraction conditions and also conduct research on the spontaneous combustion characteristics of coal and coal mass.

II. Equipment Functions:

(1) Simulation of three-dimensional gas extraction in goaf under combined extraction methods in the context of stope fractures under axial stress field conditions;

(2) Distribution of flow field (oxygen concentration distribution) in goaf and surrounding rock under three-dimensional gas extraction conditions;

(3) Variation patterns and distribution characteristics of coal temperature, oxygen concentration, and carbon monoxide concentration in goaf under different three-dimensional gas extraction parameters and ventilation parameters;

(4) Study of the coal oxidation process under the multi-field superposition of "stress-temperature-atmosphere" in goaf.

III. Technical Specifications:

Number of extraction pumps: 3

Sealing gas pressure resistance: >0.1MPa

Extraction pump flow rate: 2m3/min, ±0.5%

Triaxial servo loading: >1000t

Effective stroke of loading plate: 150mm

Temperature maintenance duration: >3 months

Pressure resistance of temperature sensors: >5MPa

Centrifugal fan flow rate: 30m3/min

Triaxial maintenance duration of loading system: >3 months

System temperature control range: Room temperature to 40°C, ±0.5°C

Temperature sensor measurement range: 0–200°C, ±0.1°C

Pressure sensor measurement range: 0–5MPa, 0.25% FS

Mixer: 100L

Loading mechanism: Four sides (left, right, top, rear)

Number of reserved extraction boreholes and sensor interfaces: 240

Gas pressure sensor measurement range: -0.02–0.02MPa, 0.25% FS

Internal dimensions of the model frame: 3m × 2m × 1.5m (length × width × height)