Study On Explosion Risk Assessment Method And Prevention Of Sulfide Dust

Sulfide dust is at the risk of explosion,which is a major potential safety hazard in mine production.To explore the explosion risk evaluation methods and preventive measures,the composition,ignition energy absorption and dispersion of sulfide mineral dust were studied using literature investigation,theoretical analysis,experiment and numerical simulation.The comprehensive evaluation method of explosion risk of sulfide mineral dust and targeted preventive measures were put forward,which can provide a decision basis for mine.The main research contents and results are as follows:(1)Based on the field investigation and explosion theory analysis,the explosion risk evaluation model of sulfide dust was established.The production characteristics of sulfide mineral dust,ventilation conditions and operation characteristics were analyzed.The conditions of closed space and oxidant already exist at the production site.The conditions of dispersion concentration,ignition source and flammability occasionally exist.Taking composition,ignition energy and dust concentration as evaluation indexes,the explosion risk evaluation method based on occurrence conditions was established,and the explosion risk was divided into four grades.Finally,the preventive ways to break the conditions of explosion were put forward.(2)Through literature investigation and statistical analysis of explosion data,the prediction model of explosion pressure was established.The components of sulfide dust were classified according to redox properties to form indexes such as oxidation component index,reduction component index and additive component index.The correlation coefficient between the reduction component index and the peak explosion pressure reaches 0.993.The explosion pressure prediction model was established,which can accurately predict the explosion pressure of sulfide dust.(3)Through the ignition test of sulfide dust,it was concluded that the sulfur content plays a decisive role in the ignition energy of sulfide dust,while the moisture content has a dual role.13 groups of samples with different sulfur content and moisture content were prepared,and the ignition test platform was set up.The results show that sulfur content plays a leading role in its ignition state.The water in sulfide dust can promote the reaction as the reaction medium and participating substances,but too much water will inhibit combustion.Finally,the targeted management of the ignition source and the methods of wet operation were put forward.(4)Through the transient numerical simulation,it was concluded that the main gathering positions of sulfide dust in the ore drawing roadway are near the chute and return air shaft.And the concentration of sulfide dust is the highest during the ore unloading operation in the chute.The temporal and spatial dispersion characteristics of sulfide dust in the process of ore drawing operation were obtained using FLUENT software.The results show that the mass flow of the dust source determines the maximum dust concentration,and the wind speed has a dual effect on dust migration.Finally,the comprehensive dust reduction measures of water curtain and dynamic ventilation were put forward.