| RUS | UKR | DonNTU | Master's portal |
Substantiation and actuality of the theme
The goal and tasks of master's work
With increasingly complex geological and mining conditions of mining coal seams to ensure safety in coal mines is necessary to apply a set of technical and organizational measures. One of the main activities is prevention education and early detection and elimination of local concentrations of methane in the preparation and clearing mines.
This is due to the fact that local clusters are formed even under normal ventilation of the formulation and may be the cause of accidents involving personal injury and material damages. Because of the local clusters are more than 80% of methane-air mixture ignition in the coal mines. In addition, local concentrations of methane significantly hamper the speed of working, which leads to the loss of coal mining.
On ways to combat this natural phenomenon currently employs a huge number of specialists in the field aerology.
Therefore, the need to study local concentrations of methane in the mine to them. AF Zasyadko and development of measures to prevent their occurrence and elimination, no doubt. And also has a very important practical significance for the coal mines of Donbass and Ukraine in general.
The purpose of the work — to explore the local accumulations of methane in the AP "Mine it. AF Zasyadko "and to develop measures to prevent their occurrence and elimination.
Problems solved in the master's work:
1. Carry out an analysis of local education (the bulk and layers) concentrations of methane in the mine workings of the mine.
2. Correct schema mine ventilation based mining stocks on the seams and l4 m3 in 2012-2015.
3. Run prediction of methane production in the excavation sites and making preparations for working off inventories
4. To calculate:
• air flow for ventilation shafts at working stock;
• the maximum allowable for the gas pressures on the breakage face in layers of m3 and l4 when working out in 2012-2015.
5. Provide justification for the application of ways and means to prevent the formation and elimination of local concentrations of methane in the mine underground workings during mining operations in 2012-2015.
6. Make a choice and justify:
• the application of ways and means to prevent formation of local accumulations of methane in the mine excavation sites;
• parameters of the ways and means of prevention education and the elimination of local (bulk and layers) concentrations of methane at the excavation sites and other means of ventilation in the mine workings of the mine.
7. Describe measures to ensure safe conditions for operating the methods and means of prevention education and the elimination of local (bulk and layers) accumulations of methane in the mine workings of the mine.
8.Podschetat costs to implement the proposed measures for prevention education and the elimination of local (bulk and layers) concentrations of methane.
The object of study — Zasyadko Mine, explore the local accumulation of methane.
Subject of research — local (bulk and layers) accumulation of methane in the mine workings of the mine.
Practical value — given practical suggestions on prevention and elimination of local accumulations of methane to the conditions of the mine.
Mine workings in coal mines are usually aired by turbulent air currents. Despite this, the methane released in the making, mixed with air at once. His concentration equalized only at some distance from the source of outgassing.
The distribution of methane in ventilation air depends on the location of the source of methane in the generation, gas flow from the source, the speed and structure of the ventilation flow. In connection with the possibility of uneven distribution of gas in cross-sectional area of developments in current "Rules of Safety in Coal Mines" provides the rate of methane on its local cluster. [8] Local accumulation of methane - is congestion in some parts of developments with densities greater than the average over the cross section generation. Hazards are local concentrations of methane with a concentration of 2% or more. As a rule, local clusters, including those in dangerous, the average cross section making the concentration of methane does not exceed the norm for a given air flow.
All the local accumulation of methane, which are most often found in the pre-treatment and workings can be divided into main types: layers at the roof, in the hollows of bolting, a continuous miner; in wells, have faces of development workings; a jumper to isolate and develop goaf ; from rubble of the bands in windhole; have mates lavas with redeemable workings; in mining combines, in a recess of treatment workings; a mobile scraper conveyor; in uglespusknyh wells at their places of zabuchivaniya. [1]
With a high of methane in areas of the mine. AF Zasyadko main way to deal with local accumulations of methane in the ventilation openings redeemable deadlocks is an isolated drainage of developed space with gazootsasyvaschih installations.
The method consists in the fact that methane-air mixture in a rigid vent pipe or nepodderzhivaemy workings assigned to off-site, where the mixing chamber is diluted to safe concentrations. Removal of accumulations of gas provided by the suction of methane-air mixture with a methane content of not exceeding the lower explosive limit, sources with high-traction - gazootsasyvayuschih centrifugal fans. The main drainage scheme shown in Fig. 3 and Fig. 4. [9]
At many mines, ventilation processes determine the load on the lava and the pace of developments. Feature of the mining industry are ever-changing work. Mining engineer should be able to anticipate these changes and to quickly make the right decisions to ensure the jobs required amount of clean air and the organization of efficient removal of harmful gases and dust. Under the conditions of such emergencies as a methane explosion, the ventilation mode adopted must ensure salvation caught by accident in the mine people and its rapid elimination. [13]