| Ventilation is sometimes described as the lifeblood of a mine. Mine ventilation is very important for safety production in underground mines. With the depth and strength increasing of the mine, many touch issues, e. g. higher temperature of rock, longer roadways, larger resistance, more compressed heat generated by airflow, more difficulties of airflow adjusting, more leakage, more pollutants and wet, etc. will occur in the future. Therefore, mine ventilation will play more significant role.Currently, many nonferrous mines in China will reach at 500 to 1000 m depth (this depth is defined as sub-depth in the thesis). The problems described in above will become more serious. At the same time, the dust prevention will also be more difficult. In this thesis, a typical nonferrous mine named Tonglushan Copper and Iron Mine (TLSCIM) was selected as the research project, because it is the main mine of Daye Nonferrous Metal Company and a famous old mine and its mining depth is at 500 to 800 m. The ventilation and dust pollution issues of TLSCIM can also considered as the common problems in similar mines. Combined with the practical situations and conditions of mine ventilation and dust prevention of TLSCIM, a lot of investigations were conducted and some fruits were achieved as follows.(1) Based on a systematical literature reviews on the mine ventilation and dust controlling technology, optimum approach for mine ventilation was carried out and the research results were used in the mine ventilation system improvement and network analysis of TLSCIM.(2) By making detailed in-situ investigation and measurement, lot of information and data of mine ventilation and dust pollution were obtained. Accordingly, the suitable assessment of the mine ventilation system of TLSCIM was finished.(3) Depending upon analyzing the data and relevant information, the digital model of mine ventilation system of TLSCIM was set up. Various plans of improving the mine ventilation were obtained by network analysis technology. These works are the foundation of improving the mine ventilation system and getting the optimum ventilation models.(4) Based on the mine ventilation network analysis and other works, the optimum planning of new mine ventilation system was put forward, including -425m~-245m and -725m~-425m levels networks, position of main and auxiliary fans, airflow adjusting constructions, vane angle of main fans, large diameter tube for heading ventilation, cost, etc.(5) By considered the practical requirements of airflow adjusting of TLSCIM, the possibility of air curtain used for adjusting airflow was analyzed. The effective pressure of air curtain for sealing airflow, the resistance of air curtain, the efficiency of single and multi curtains, etc. were calculated and analyzed. Also, booster with or without sealing were discussed and investigated to use in adjusting airflow.(6) According to the fault tree analysis method, the relevant factors and reliability of mine ventilation system of TLSCIM was analyzed. The un-stabilized fault tree of mine ventilation system was set up and accordingly the effective measures of increasing the reliability of mine ventilation system were put forward.(7) Taking the chemical suppression of dust as the approach, the wetting agents for controlling dust were investigated. After analyzed the samples of dust of TLSCIM, the type of wetting agent was selected and its preparation method was obtained. Also, solution of surfactant adding chloride for improving the wetting behavior was tested. An optimum compositions of wetting agent for dust control of TLSCIM was innovated.(8) Based on the compositions of wetting agent in laboratory, a spraying system of water adding wetting agent for controlling the dust pollution in ore drawing station of TLSCIM was designed. The designing work includes the spraying system, nozzle selection and installing position, water supplying system, water quantity requirement, etc. Also, the affecting factors to dust suppressing efficiency, the efficiency by ventilation and water spraying and the cost of spraying station were analyzed.(9) The dust releasing mechanism by dynamic airflow when ores are drawing into an ore pass was analyzed. The effective measures for controlling dust releasing were put forward.(10) At last, comprehensive measures for mine ventilation management, dust suppression management and work safety and health administration were listed.The key technologies for mine ventilation and dust control described in above were used in the project of deep mining engineering of TLSCIM. The practical application verified that the research fruits are effective and can be widely applied in other similar mines.
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