| Plateau hypoxia is one of the main factors restricting the operation of high-altitude metal mines.In this paper,the theoretical analysis of mine ventilation,simulation research and field experiment verification are used to study the oxygen diffusion law in high-altitude metal mine based on different ventilation and oxygen supply parameters.The optimal ventilation and oxygen supply scheme aim to improve the working environment of mine personnel,ensure the safety of artificial oxygenation,and maximize and rationally utilize limited oxygen resources,and the main research contents and results are as follow:1)The main influencing factors of the ventilation and oxygen supply system in high-altitude metal mines were analyzed and summarized,the advantages and disadvantages of local ventilation methods in plateau mines were analyzed,and the jet type artificial oxygenation method suitable for high-altitude metal mines was determined;various CFD simulations were compared and analyzed.According to the characteristics of the software,the ANSYS-Fluent software,which has the advantages of good compatibility,high stability and wide application,is selected for the simulation study of oxygen diffusion in plateau mines.2)Based on the 3720 trackless flat roof of Pulang Copper Mine,a 3D physical model was constructed,combined with the main influencing parameters of ventilation and oxygen supply in high-altitude mines and the actual situation of the mine-used mobile artificial oxygenation device,respectively,from the oxygen outlet wind speed,oxygen outlet position,fan outlet height,The control variable method is used to conduct orthogonal experiments in terms of oxygen supply quality per unit time,to study the diffusion law of artificial oxygen enhancement in high-altitude metal mines.When the altitude is 3700 m,the air density is 0.863 kg/m~3,and the oxygen content is 0.198 kg/m~3.According to the calculation of the air volume for the workers to achieve moderate working intensity,the breathing air volume is 40 L/min,and the oxygen consumption is 1.5 L/min.It is necessary to increase the relative mass fraction of oxygen by 6.0%in the Pulang copper mine at an altitude of 3700 m as an oxygen supply index.The results show that the air flow at the oxygen outlet plays the main driving role and the diffusion distance is about 2.5 times the value of the wind speed,and the natural diffusion plays a major role beyond this distance.3)Through a large number of oxygen diffusion simulation simulation research and field experiment verification,the experiment shows that when the oxygen outlet wind speed at the fan outlet of the mine mobile artificial oxygenation device is set to 5 m/s,the center of the fan outlet is 0.5 m away from the roadway wall and the distance from the ground is 0.5 m.When the height is 1.6 m,the diameter of the fan section is 0.4 m,and the oxygen supply per unit time is 0.0092 kg/s,it is the optimal artificial oxygenation scheme. |
