RU1257225C - Method of preventing rock bumps - Google Patents

Description

l / l3o6peTeHi / se belongs to the mining industry 14 and can be used to combat dynamic, gas-dynamic phenomena and dust in coal mines.

The purpose of the invention is to increase the effectiveness of prevention and sudden emissions in difficult mining conditions by taking into account the condition of the coal seams and improving the technology of maintaining humidification.

In FIG. t is a schematic diagram of an arrangement of injection wells; in FIG. 2 is a picture of the calculated parameters of hydroprocessing under complicated mining and technical conditions, when the treated outburst hazardous layer is influenced by mining operations on adjacent SVITU strata.

The following symbols are used in the figures: production 1, formation 2, wells 3, filtering part 4 of the well, production 5 along the coal seam; sealing device 6, a strong layer of rock; superficial layer 8, rear 9, diagram 10 of the voltage; zones 11-13 with different loading conditions. The method is implemented as follows. . . ,, From existing mx or specially pass. zbl / zi of the treated area of the workings 1 pro (3uri8a 0t perpendicularly go obliquely to the processing soil 2 wells 3 and drill through the formation so that their filtering part 4 was located at a distance S: 0.3. where I is the zone reference pressure from the nearest exposed edge of the reservoir in conjunction with the working hole 5 or mined-out space. Through the drilled well, the stress state of the array is estimated using any of the existing methods. The most rational geophysical methods, for example, seismic cue.

Under the conditions of a quiet occurrence and the absence of mining on adjacent formations, the stress state is assessed by two or three wells w, with good convergence, the results are distributed over the entire area or its significant area. 8, in case of variability of the mining and technical situation, an assessment is performed in each well and the calculation of the injection parameters is carried out specifically according to the results obtained in these wells. It is also possible to use calculation methods for assessing the strength of the array under conditions when the confidence in the use of calculation methods is quite high.

In the process of drilling a coal seam with a borehole, coal samples are taken and, before the start of hydrotreatment, the full moisture capacity Wn and the natural

humidity angle We.

After performing work on an experimental assessment of the strength of the array and physical properties, the corners of the well are equipped with an injection pipe set, this

wells are sealed so that the sealing device 6 covers the most durable layer of rock 7, Well) is drilled with a distance between them, determined from the following approach.

The nominal humidification radius LO is set with respect to the geostatic conditions of unloading the array {o un). For different pools and varieties of coal, this distance can be different and is determined experimentally or from the expression

R about

V

Q

l; m N

where Q is the rate (flow rate) of water injection,

t is the injection time, h; m formation capacity, 7l.

 The actual radius of action of the well is taken into account the stress concentration coefficient from the expression

35

R roe

, (.- 0

where a is an empirical coefficient equal to 0.25-0.5;

K stress concentration coefficient,

The stress concentration coefficient K is determined from a previously drilled nearest neighboring well in which a state stress assessment has already been performed. The distance between the wells is determined according to the condition L 1.5 R so that the Regions of the adjacent wells overlap and provide uniform wetting of the array over the area.

The pressure of the water in the stavka when pumping is established; 1 is proportional to the acting stresses from the expression, 74KuN,

The rate of moisture in the coal is determined

as the difference between the total moisture capacity and natural moisture angle from the expression

N a {Wn-Wa),

where Wn - full moisture capacity uglp,%;

We - natural humidity coal. %;

a-coefficient taking into account the ropflO-geological state of the formation, which is experimentally taken equal to W.5

After the injection is carried out, the humidification efficiency is evaluated, for which a control well is drilled at a point equidistant between the injection wells and 10 coal samples are taken for humidity.

8, the condition Wy S 0.85 Wn is introduced as an efficiency criterion.

If the sample humidity is below critical, additional water is injected through this well 15, and then the effectiveness is monitored in the middle of the interval between 20 adjacent wells, halved by half due to the undergrowth;

On fit. 2 at the entrance, where there is a highly hazardous formation 2, which is undergoing processing. Additions & are covered by formation 8 with a 24 m interspace. On the overlay 25 formation, a Ts5eyk 9 50 m wide is left. Determination of k0af; financial stress concentration component for the given conditions is carried out using the piscMeTHbiW method, 30 The results are shown in the tO plot in Fig. 2. from which, that the center 4 and the center achieves N. under the whole space under the worked Space the floor still reaches more, and under the action of lava –0.3 at N. On the basis of the m "% assessment of the allocation of the zone with different words mi loading; the ti zone under the target with a specific value of b 1.5; zone 12 - k 0.45 and zone 13 - fc 0.3.40

The initial data for calculating the parameters of the hydraulic treatment of the formation are as follows: the depth of the development of the formation, the volumetric weight of the overlying rocks is 2.5 tons / m; the thickness is 45 layers m 2 m; natural humidity We “3.3%; full moisture capacity Wn 5.8%.

Pumping water is carried out by a NVU-30 unit with a nominal load of 30 l / min and an actual 50 / min or 0.9 g1.2 m / h. Technological conditions Site preparation requires Verification of injection in 1 month, yr atom

the net operating time of the discharge equipment does not exceed 160-180 hours. Following the initial data, the humidification rate is 25 l / m. The radius of influence of the injection well in a single formation at K 1.30 m. The radius of influence, taking into account the stress concentration coefficient for zones 11-13 with a 'OD; RII "23.3 m. Ri2 39.4 m, Ri3 42.5 m. The distance between the wells along the formation strike for zones 11 is Li g 35 m.

According to the dip of the formation, two wells are located underneath the whole, at a distance between their filtering parts of 35 m and one upper and lower discharge zones one by one. In this case, the location of the well in the upper discharge zone is checked according to condition a 2: 0.31 16.5 m, 1 55 m, since there is a development 5.8 near it; in the example, it can withstand Li2: 2 28.5 m 16.5 m.

To ensure the interaction of wells located in different zones, the distance between them is taken equal to half the calculated

1 11-12

35-fS9

 4tm.

L ft-ifs

 3S + 64

 49m

Regulatory volume injection of water into each of about (I { "1N already determined based on the rules u8lvzhn € 1N14 pyasta capacity and the distance between the wells For zone 11: VH - 4 × M {y1Sh..) .5 (they | z 415 for zone 12: VH S60 m. for zone 13: Un 692 m. The discharge pressure for the zone of influence of the rear of the Pntt is 68 kg / cm: d zones 12.13

Prt} 2 5tKfc / CM,

 Rk.

(56) ftJSTeHT Fraction No. 1400838.ext. E 21R W4.

Unified coal seam engineering specifications. Dangerous by sudden throw away coal and gas. M., 1974. p. 241-314,

Form my la and 3 gain

METHOD FOR PREVENTING ROCKS. SUDDEN EMISSIONS AND SUPPRESSION OF COAL DUST, including drilling wells from previously completed workings, sealing them, determining the stress state of the formation, the natural moisture content of coal, injection, water into the formation, determining after injection the total moisture content of coal and evaluating | characterized in that, in order to increase the efficiency of preventing mountain bumps and out-of-phase emissions in difficult mining and technical conditions by taking into account the state of coal seams and improving the technology of management, it is moistened And previously passed wells excavation

cross-bed formation over empty rocks, determination of the stress state of the formation is carried out in the area of intersection of the wells with wells, and pressurization of the wells is carried out in the most durable layers of the drilled thickness of the rock, while the distance between the wells is taken inversely proportional to the acting on the processed

0 part1, for example, 1m, and the wells intersect the formation at a distance from the workings passed on it at least 0.31, where I is the zone of reference pressure, and the moisture rate is set by the formula

5 N-a (Wn-We), where Wn is the total moisture capacity of coal,%; Wg - natural moisture content,%; a - coefficient taking into account the geological state of the reservoir.

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Editor S. Lisina

Compiled by GVasyuchkova

Tehred M. Morgenthal Corrector S. Shekmar

Order 3241

Circulation

NGO Search for Rospatent 113035, Moscow, Zh-35, Rauska nab., 4/5

Production and Publishing Plant Patent, Uzhgorod. Gagarina St., 101

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