Method to predict outburst hazard of development drifts
SUBSTANCE: method consists in detection of mining operations performance depth from surface, section of a mine by coal, pressure of gas in an untouched bed massif, coefficient of weighted average coal strength in a bed, coal adhesion, stress in a coal massif along a face line and area of coal massif unloading in front of the face. The specified data is substituted into a mathematical formula, with the help of which prediction of outburst hazard of a development drift R is made. If R>0, the bed is related to outburst hazardous, and if R<0 - to safe regarding coal and gas outbursts.
EFFECT: possibility to apply the method both when tunnelling and at the design stage due to use of technical characteristics of mines carried out under similar conditions or being at the stage of design solutions.
The invention relates to the mining industry and can be used to predict the outburst zones when driving or design development workings.
There is a method of prognosis outburst areas, including the drilling of a borehole parallel to the longitudinal axis of the generation, measurement pointervalue the initial velocity of the gas and exit of the drilling rubble, the definition of the indicator of the outburst and the separation layer on outburst-hazardous and non-hazardous areas (Puzyrev V., N. Vershinin, Khashin NR. and Packagin VA Method of forecasting the outburst layers and monitor the effectiveness of preventive measures in small diameter wells. Proceedings Of VostNII. 20. Kemerovo, 1973, s-174).
The disadvantage of this method is the lack of evaluation of the outburst of the reservoir in disturbed areas, when the output of the rubble does not correspond to the stress distribution ahead of a moving face. Furthermore, the method allows to determine the position of outburst areas only a short distance from the chest of the face (up to 5 m).
As the prototype accepted method of determining outburst zones when conducting preparatory development, including the drilling of a borehole parallel to the longitudinal axis of the workings at a depth of 15-30 m, determination of hardness of coal, 5-10 see its value calculated active power, causes the matter of the release, and passive forces that prevent the release, and the index of the outburst is determined by the well-known formula
where Fa- active power, causing the release;
Fp- passive forces, preventing the release.
When Rin>0 the area belongs to the outburst, and when Rin<a 0 - to neveraskopen (USSR author's certificate No. 979644, CL E21F 5/00, declared 17.12.1975, the authors Vghginen, Beglarian, Wearage, Welbalance, Dry and Bscreen, published in 1982, B. No. 45)Preimushestva known method is that it leads to reduction in the use of protivovirusnyh activities in the preparatory workings. The disadvantage of this method is the inability to use his design of mine workings, when there will be no holes and no data on production parameters, the coefficients of the fortress of coal, the voltage on the data line of the face, etc.
The technical result of the use of the invention is the possibility of its application as the excavation and at the design stage due to the use of the technical characteristics of the mine workings, passable in similar conditions or under design decisions.
The method of prediction of the outburst mines, including the determination of the depth of mining RA is from the surface, section mining for coal, active and hindering forces acting on the coal in the bottom space can move him in the face and forecast of the outburst on the difference between these forces.
The difference is that further define the gas pressure in the intact rock mass layer, the coefficient of the weighted average of the fortress of coal seam grip coal, the voltage in the array coal slaughtering and coal unloading area of the array in front of the face, and forecast vibrocompaction carry out mathematical formula
where S is the cross-section generation, m2;
f - weighted average of the hardness of the coal;
Pois the gas pressure in the intact rock mass, determined directly by the formula
H - depth of mining from the surface, m;
- the voltage on the data line of the face, directly measured or
determined by the formula
K - coefficient of coupling of coal, directly measured or determined by the formula
X - discharge zone the preparatory development of m is determined by the formula
where α is a rheological parameter defined by the formula
lW- width of the Executive body, m;
V is the average speed of advance of slaughter, m/day.
When R>0, the layer is referred to outburst, and when R<0 for non-hazardous to sudden outbursts of coal and gas.
The proposed method for prediction of the outburst can be used for passable roadways, when parameters generation and coal characteristics of the array are used directly by measurement, or for projected openings, when the parameters and specifications are accepted on the basis of design decisions or by analogy with other ongoing workings.
The proposed method for prediction of the outburst illustrated by the scheme of the mechanism of unleashing a sudden outburst of coal and gas in the preparatory development, shown in the drawing. The diagram shows the situation at the time of extraction of coal Zachodni L and shows the state of the array coal zone I-III at the time of occurrence of the outburst of the situation. When the magnitude of zagadki L is such that the resultant of the forces of gas pressure in some close to the newly formed face parallel to the crack will be more limiting to the resultant force of the resistance of the coal separation, untied outburst. As will be rejected more remote from the original position of the layers occurs rapidly is a kind of transfer of separated pieces of coal from the zone of high pressure gas into the low-pressure zone due to which there is an effect of the gas crushing coal. Thus, ahead of preparatory development held for outburst layer, formed three zones (I-III)that are different from each other according to the state of the coal of the array. Closest to the slaughter zone I consists of a compressed moving rocks intensively destroyed the coal mass, having a low filtration properties. The next zone II is characterized by the fact that it forces the rock pressure formed a dense network oriented parallel to the bottom of the crack, which accumulates a significant amount of under pressure free gas. The third zone III is the transition from the elastic state of the array to the plastic-elastic. Significant factors contributing to the preparation of coal array to implement energy of free gas, such as a change along the strike of the seam strength properties of the coal massif (f, R0,, K, X, and others) towards their reduction and technical parameters of conducting production (cross-section generation for coal's value Zachodni average daily rate of podvigina slaughter v, width of the Executive body of the lWand others). The proposed method allows not only to determine the specific conditions of the possibility of outburst sieve the Nations, but also to identify the most significant factors and to determine the impact on them to prevent the outbreak of sudden outbursts of coal and gas.
Forecast of the outburst carry out mathematical formula
where S is the cross section of the driven working, affects the extent of the region of reduced stress, m2;
f - weighted average of the hardness of coal is determined by well-known methods;
Pois the gas pressure in the intact rock mass directly measured or determined by the formula
H - depth of mining from the surface;
- the voltage on the bottom line, measured or determined by the formula
K - coefficient of coupling of coal, measured or determined by the formula
X - discharge zone preparatory development, determined by the formula
α - rheological parameter defined by the formula
lW- width of the Executive body, m;
ν is the average velocity prodigene slaughter, m/day.
On the basis of the performed measurements and calculations according to the formulas obtained the following source data: S=14 m2; f=0,3; Po=3,45 MPa; N=420 m; =0,13 MPa; K=2,2; X=26,79 m; α=3,88 1/h; lW=0.3 m; ν=4 m/day. Substituting these values into the formula to determine the value of R=1,29. Since R is a positive value, then the result of the forecast of the outburst is that this preparatory development refers to prone to sudden outbursts of coal and gas.
A significant advantage of the proposed method for the prediction of the outburst mines is its high efficiency and the possibility of using directly measured when driving this generation or in similar conditions and design parameters, making prediction of the outburst at the stage of penetration, and at the design stage of production.
The method of prediction of the outburst mines, including the determination of the depth of mining operations from the surface, cross-section mining for coal, active and hindering forces acting on the coal in the bottom space can move him in the face and forecast of the outburst on the difference of these forces, characterized in that it further determine the gas pressure in the intact rock mass of coal seam grip coal, the voltage of coal slaughtering and the discharge zone of the coal face in front of the face, and the forecast of the outburst carry out mathematical formula
where S is the cross-section generation, m2; ƒ - weighted average of the hardness of the coal; P0is the gas pressure in the intact rock mass directly measured or determined by the formula R0=0,092(H-45), MPa; H - depth of mining from the surface, m;- the voltage on the data line of the face, directly measured or determined by the formula, MPa; K - coefficient of coupling of coal, directly measured or determined by the formula, MPa; X - discharge zone preparatory development, determined by the formula
α - rheological parameter defined by the formula, 1/h; lW- width of the Executive body, m; ν is the average velocity podvigina slaughter, m/day; R>0, the layer is referred to outburst, and when R<0 is not dangerous to sudden outbursts of coal and gas.
SUBSTANCE: method involves supply of frozen fluid obtained by mixing with liquid gas to the worked-out space. In addition, distribution of coal dust supplied to the worked-out space is determined as to particle fractions. Distribution of the obtained frozen fluid particles as to fractions is equal to distribution of coal dust as to particle fractions.
EFFECT: improving the prevention efficiency of coal self-ignition in mines.
SUBSTANCE: method includes drilling of wells between earth surface and roof of an underground mine, erection of an insulating barrier link by supply of a hardening material into an underground mine whenever an emergency occurs related to self-ignition of coal. The section of the underground mine in the place of erection of the isolating barrier link is worked with increased height, which is gradually increased from borders of this section to its middle. The well is drilled between earth surface and a point with maximum height of the underground mine, and supply of the hardening material into a mine is carried out to complete filling of the section with increased height with hardening material. On the borders of the section with increased height of the mine prior to start of hardening material supply into an underground mine, barriers are installed, width of which is accepted as equal to or less than the width of the mine in the place of barriers installation, and the height of the barriers is determined using a special expression.
EFFECT: increased reliability of isolation of an emergency section in case of underground fires and reduced material and labour inputs.
SUBSTANCE: set of inventions relates to safe deep mining of solid hydrocarbons. Proposed method proceeds from continuous ground monitoring of geodynamic state of massif and seismic activity of bed roof and bed working on surface area covering bed headway in real time by passive prospecting seismology methods. Obtained results are automatically processed to isolate zones with abnormally-high seismic energy emission, define their area and depth coordinates so that map of anomalies of seismic emission. Maximum magnitudes of seismic emission are used to define coordinates of slope ratio of coal bed fracturing well. Development of main cracks is forecast from the well by the method of double refraction of transverse waves from surface excitation source. After fissuring, direction of main crack development in face bulk is controlled. Area is drilled from surface in directions of main crack development to pump methane out from the wells. With seismic emission decreasing, possibility to extract coal is forecast.
EFFECT: higher safety and intensity of coal extraction.
3 cl, 3 dwg
SUBSTANCE: previously laboratory analysis is carried out on coal from a bed and its packs to detect availability of elements and substances in them that may create compounds with water; natural cracking is detected, as well as cleat in the coal bed; wells are drilled from a bottomhole by coal, with length more than by 1 m of the mine skirting cycle; water is injected into the bed with continuous measurements of the methane, water pressure, injection time; the mine is tunnelled for the value of the hydrated bed with the speed that does not exceed methane release within permissible norms; in the area of bed hydration blast holes are drilled in the sides of the mine at each cycle to detect the hydration area. During arrangement of the mine, parameters are varied, which are related to injection of water into bed, maximum reduction of the released methane, optimising arrangement of the mine.
EFFECT: higher efficiency of development of gas-bearing coal beds.
SUBSTANCE: method to prevent explosion of a gaseous mixture includes removal of combustible gas from a monitored room through ventilation. At the same time it is additionally burnt by periodical ignition, with one or several electrical dischargers, controlled with a timer. Dischargers are installed in the monitored room around potential areas of combustible gas leakages at the minimum distance sufficient for its ignition. The ignition period is defined with the minimum time for creation of an explosive gaseous mixture around the discharger and is set with the timer's programme.
EFFECT: higher efficiency of preventing explosion of a gaseous mixture.
SUBSTANCE: method includes well drilling between surface and roof of underground mine working, delivery of hardening material to the mine working in case of emergency situation related to coal fire breeding. Section of underground mine working is driven in the place of isolating barrier wall erection; height of mine working is increased towards the middle of the section. Well is drilled between ground surface and point of maximum height of underground mine working. Hardening material is delivered to the mine working till mine working section driven with various height is completely filled. Maximum height of mine working in the middle of this section is determined by expression hmax≥hb+tgφ·b/2h where hmax is maximum height of underground mine working on the section of isolation barrier wall erection, m; hb is height of underground mine working outside the section within which isolation barrier wall is erected, m; φ is angle of hardening material spreading, degrees; b is width of underground mine in the rough, m.
EFFECT: improving reliability of emergency section isolation during underground fire.
SUBSTANCE: method includes measurement of concentration of tracer gases in air at outlet from accumulation of coal and rock providing that their background values have been measured. Additionally quantity of water vapour in air is determined and concentration of tracer gases in dry air is determined by formula cc = c / (1 - Fm), where Cc - concentration of tracer gases in dry air, fraction units; C - measured concentration of tracer gas in sample of mine air, fraction units; Fm - fraction of water vapour in unit of mine air, fraction units.
EFFECT: improving efficiency of detection of coal spontaneous ignition processes.
SUBSTANCE: automated system for control and prevention of explosion of dust-methane-air mixture in complex mechanised mining face consists of irrigation pipeline, high-pressure pump, low-pressure and high-pressure pipelines of automated system with electrical valves and solenoid valves, nozzles for waterspray, measuring instruments for methane, carbonic oxide, humidity, dust level of mine atmosphere and ash-content in dust, air flow rate in the beginning and in the end of mechanised mining face, measuring instruments for methane content and position sensor installed directly on cutter-loader, measuring instruments for water pressure in pipelines connected via data transmission modules to communication lines and controller, control unit with lines for control of electrical valves and solenoid valves. The system differs in the fact that during constant control of measuring instruments readings, position of cutter-loader in mining face, electrical valves and solenoid valves, which are recorded to "black box", divergence of input and output parameters from specified values and proximity of content of methane, dust and its ash-content, carbonic oxide in mine atmosphere to lower level of explosion of dust-methane-air mixture is analysed continuously, control actions are developed with prefacing for dispersed supply of fine water calculated volume from high-pressure pump through high-pressure pipeline, electrical valves and fine-spray nozzles to space of complex mechanised mining face in order to provide condensation point in mine atmosphere considering actual temperature. At that fine water is supplied opposite to air flow in mining face before and/or after cutter-loader considering direction of its movement and system transportation lag.
EFFECT: improving control and preventing explosion of dust-methane-air mixture in complex mechanised mining face.
SUBSTANCE: method includes well drilling between the surface and roof of isolated underground working and construction of isolating barrier on the way of fire movement in the isolated underground working and pumping the isolating filling agent into the working. Note that the cavity is created along the whole width of working roof, for example, by blasting the explosive substance charges in the lower part of the well, the height of which is defined by proportion. Grinded rock is supplied from the surface to the rock crushed by explosion and rocky embankment is created on the ground of isolated underground working. Quick-hardening cement is supplied to the rocky embankment, note that the supply of quick-hardening cement is done at time intervals equal to the period of quick-hardening cement setting. The supply of quick-hardening cement is stopped at the height of isolating barrier satisfying the proportion.
EFFECT: increase of reliability of emergency area isolation at underground fires and reduction of material and labour costs.
SUBSTANCE: mortar includes cylindrical housing, container with dry chemical powder barred with diaphragm at outlet, piston, chamber with preset pressure of gas in it, gas generator. Mortar is started by electric impulse of remotely placed detector tracking the situation independent of its type. Chamber with preset pressure is connected to cavity in which gas generator is located, separated from container with dry chemical powder by membrane to open. Container is provided with movable partitions, the first of them is located with a gap to membrane and has through selection chordwise in its lower part. Mortar housing is provided with elements providing its fastening on carriage or to gas outlet main pipe or to its discharging vertically oriented branch.
EFFECT: improving safety, reliability and efficiency of distance protection of controlled space from fire and explosions upon localisation of these factors at distant approaches from the device independent of type of used detector and mortar space orientation.
10 cl, 6 dwg
FIELD: mining industry; methods and devices for localization of explosion of methane-and-air mixture and coal duct.
SUBSTANCE: proposed device includes bin filled with flame suppressing powder and provided with filling neck which is closed with cover and easily breakable diaphragm at its outlet. Device has pneumatic cartridge coaxially located in perforated intermediate chamber which is coaxially located in its turn in bin; it is cone-shaped or cylindrical in form. One end of intermediate chamber is rigidly secured on inner end wall bin and other end is rigidly secured at bin outlet in spryer made in form of swirler. Pneumatic cartridge has several working chambers connected with exhaust holes, actuating mechanism with spherical movable supports engageable with spring-loaded stepped piston which is located in main working chamber closing its holes; subsequent exhaust holes of working chambers are closed by spring-loaded slide valves having bypass passages of equal section which are located in working chambers dividing them; cartridge has front chamber between its housing and sliding sleeve containing gas-forming chemical agent. According to another version, device has two base modules which are connected by mirror image; each module has pneumatic cartridge and perforated intermediate chamber.
EFFECT: enhanced efficiency.
20 cl, 15 dwg
FIELD: mining industry.
SUBSTANCE: method includes solution of crystals of samples in salts solution and separation of volume of gas in measuring tank, isolated from atmospheric air. Salt samples are crushed mechanically directly in salts solution. From measuring tank gas sample is extracted to determine its composition.
EFFECT: higher precision.
FIELD: mining industry.
SUBSTANCE: heat waves suppression device consists of mine channel with well sections made therein. Each well of section is provided with conic aperture at entry into rock, and at end of well - by chambers for destroyed rock, remote from each other and from longitudinal channel axis. Each section of channel wells is made with saw-like surface, projections of which are directed against possible direction of air strike wave. In recesses of sections conical apertures are positioned, from which wells are placed at sharp angle ±(10÷70°) to direction of air strike wave.
EFFECT: higher efficiency and durability.
FIELD: mining industry.
SUBSTANCE: wall has caved-in rock, being in passage with cuts and fully closing the latter, which is formed by prior driving of a fan of coupled ascending drifts, loading charges therein and detonating the latter in order from ends of fan to its center. In rock before wall two mated side horizontal dead-end tunnels are made at sharp angles ±40÷60° to direction of air strike waves and with cross-section area, equal to area of main passage cross-section, and with length 5÷15 of dimensions of passage width. On the side of approach of air strike wave angles of mating surfaces of protected passage and dead-end tunnels are made rounded. After protection from air strike wave and providing for possible crossing of passage rock of wall is stored in horizontal dead-end tunnels.
EFFECT: higher efficiency, lower costs.
2 cl, 7 dwg
FIELD: mining industry.
SUBSTANCE: relation of amplitudes K of high-frequency and low-frequency portions of acoustic oscillations spectrum, generated by cutting tool into coal massif, in process of extraction. Current values of coefficient Km are compared to limit allowed value Km.lim. In that case limit acceptable value Km.lim is continuously automatically corrected in accordance to current value of methane concentration in mine atmosphere, recorded by methane control equipment, and is periodically corrected in accordance to measured hardness of coal by means of special hardness meter. Zone of coal bed is referred to as exhaust-hazardous, if Km≥Km.lim and as not exhaust-hazardous, if Km<Km.lim.
EFFECT: higher precision.
3 cl, 4 dwg, 1 ex
FIELD: mining industry.
SUBSTANCE: method includes driving main ventilation, level backup and ventilation drifts, connecting shafts and extractive block is extracted fully with following backfill. Prior to start of extraction of resources of extractive blocks at cleaning portion closed space is formed by mounting gate and isolating walls, wherein air is forced via ventilation pipeline from high-pressure ventilator. Relation of shaft pressure of air pressure Ps to air pressure Pp at processed portion during process of extraction of extractive block is set and maintained by inequality 1<Pp/Ps≤3.
EFFECT: higher safety of processing of fire-threatening beds to decreased possibility of coal self-ignition.
FIELD: protection from explosions.
SUBSTANCE: method includes building of wall around explosion-hazardous object. Wall is made of two layers, one behind another. First layer of splitters is positioned along radius on the way of explosion products coming from center with harmful dispersed particles contained therein. Second layer is positioned on the way of formed stream flows with spacing relatively to first one. Wall of second layer is made of absorbing fragments, absorbing harmful substances by impacting, and with radial displacement of absorbing fragments relatively to first layer splitters. Space between layers of splitters and absorbing fragments is filled with foam-aero-gel forming mass, interacting with gas flows. Aero-ballistic parameters, mass, number and dimensions of absorbing fragments is selected from relation VΔt≤NxA/2π, where V - average splitters flight speed, determined by pressure of explosion product, aero-ballistic coefficient and mass of each splitter and each absorbing fragment; N - number of splitters; Δt - time of gas-dynamic filtering (during passing of explosion products through layers); A - size of explosion fragment, absorbing harmful substances, concentrated by gas-dynamic jets, after passing by first layer.
EFFECT: weakened air-blast, absorbed harmful dispersed particles.
2 dwg, 1 ex
FIELD: mining industry, particularly to provide dust control in different processes by ejecting dust-laden air and entraining dust particles with liquid spray cone inside device and by separating the formed sludge.
SUBSTANCE: device has body with inlet and outlet orifices, injector nozzle, sludge trap and sludge removal pipe. Spray nozzles communicated with sludge trap through orifices of the body are arranged along inlet orifice perimeter. Sludge trap has floating valve arranged in bottom sludge trap part and installed in sludge removal pipe. Device also has dust catching sheets arranged between inlet and outlet orifices and defining working space for spray cone generated by injector nozzle shaped as expanding diffuser, which provides free spray cone penetration into sludge trap and air suction into inlet orifice. Dust catching sheets located near inlet orifice are inclined from body periphery towards spray cone axis and dust catching sheets arranged near outlet orifice are inclined from spray cone axis to body periphery.
EFFECT: increased capacity and efficiency, possibility of rational wetting liquid utilization.
FIELD: mining industry, particularly elimination of emergency situations.
SUBSTANCE: method involves closing borehole cross-section with extendable means; arranging predetermined volume of non-combustible material above the means, wherein the volume is determined from a given relation; discharging all non-combustible material in the borehole at a time and further distributing portions of non-combustible material having volumes of not less than volume of incoming water. Non-combustible material includes clay and pourable components which are laid in layers above the means, wherein clay volume is equal to pore volume of pourable component.
EFFECT: increased reliability of borehole sealing and water burst liquidation.
3 dwg, 1 ex
FIELD: mining industry, particularly for removing gaseous nitrogen directly from mine atmosphere to use thereof for fire prevention and extinguishing.
SUBSTANCE: nitrogen compressor plant adapted to be arranged in mine tunnel includes several functionally connected modules arranged in series and mounted on small-size movable platforms in maximum possible proximity to nitrogen consumer. Compressor unit is located in front of other components in direction of fresh air jet flow feeding into mine tunnel and non-used exhaust gas mixture is removed from compressor compartments during compressor stoppage along with exhaust air jet control at mine tunnel exit. Gas mixture enriched with oxygen is supplied from membrane gas-separation unit into special mixer to reduce oxygen content in above gas mixture up to safe level by forced dilution thereof with additionally supplied air. The resultant mixture is then moved into mine tunnel along with fresh air jet directed to mine tunnel zones. Membrane gas-separation unit includes several minor gas-separation units. Cleaned air flow exiting from compressor is supplied to membrane gas-separation unit through air flow separator, in which common air flow is divided into several jets. The jets are then moved to minor gas-separation units having lesser end sections through branch lines. When nitrogen consumption is reduced or when air is supplied by compressor the minor gas-separation units are automatically disconnected from separator. Each branch line includes control valve, to which control signal impulse is directed from common control panel or from system adapted to regulate nitrogen consumption.
EFFECT: possibility of continuous nitrogen production from atmospheric air directly in mine and, as a result, increased efficiency of fire prevention and extinguishing and improved safety if mining work performing.
6 cl, 1 dwg