Method of ventilation of ultra-deep horizons of underground mine during mining of sub-quarry reserves of kimberlite pipe

Abstract

FIELD: mining.SUBSTANCE: invention relates to a method for ventilation of ultra-deep horizons of an underground mine during the development of sub-quarry reserves of a kimberlite pipe. The method includes the development of a calculation model for the ventilation network, supplying air to the mine through a ventilation system of mine workings using a main ventilation fan with separate ventilation of the upper and ultra-deep horizons. The direction of the air flow is formed using ventilation structures. An underground auxiliary stationary fan for main ventilation is installed in the main air supply workings for the lower super-deep horizons. Air is supplied to ultra-deep horizons using additional mine fans. Mobile mine fans are used as additional mine fans at ultra-deep horizons. Negative regulation ventilation devices – ventilation doors – are used as ventilation structures. The operation of the main ventilation fan, the underground auxiliary stationary main ventilation fan and the mobile mine fans is carried out in the joint operation mode with flow rates in a ratio of 0.95÷1.05 / 0.57÷0.63 / 0.5÷0.53. The optimal amount of air supplied by underground mobile fans at the exhaust air collection point at ultra-deep levels does not exceed the fresh air flow rate of the underground auxiliary stationary fan supplied at the main air supply point for the lower levels.EFFECT: increased efficiency of ventilation of the lower horizons of an ultra-deep underground mine.3 cl, 4 dwg

Description

[0001] This invention relates to the mining industry, specifically to the ventilation of underground diamond mining operations. Under similar geological conditions, it can be applied, in whole or in part, to underground mining of other minerals.

[0002] A method for ventilation of a mine is known according to patent RU No. 2119060 (priority 13.05.1997, IPC E21F 1 / 00 ​​(1995.01), patent holder Joint Stock Company Uralkali, published 20.09.1998), which includes supplying air to the ventilation network of the mine using a ventilation unit, while part of the air is directed for reuse in the ventilation network of the mine, where fan units located inside the mine are used.

[0003] A known method of ventilation of a mine (RU patent application IZ No. 2004112452 / 03, priority 22.04.2004, IPC E21F 1 / 00 ​​(2000.01), applicant Open Joint Stock Company Uralkali (OJSC Uralkali) (RU), published 20.10.2005), includes supplying air to a ventilation network using a fan unit, and directing part of the air for reuse in the ventilation network using fan units located inside the mine. A single fan unit is used to supply air to the ventilation network and to direct part of the air for reuse, wherein the air directed for reuse is supplied through a fan, and the air is supplied to the ventilation network due to the ejector effect.

[0004] Also known is a method for ventilating a panel with a panel-block preparation system, protected by RU patent IZ No. 2400632 (priority 11.01.2009, IPC E21F 1 / 00 ​​(2006.01), patent holder OJSC Ural Research and Design Institute of Halurgy (OJSC Halurgy) (RU), published 27.09.2010, bulletin No. 27).The method includes supplying air from the main transport workings through panel transport workings to block transport workings to the places where mining operations are carried out and removing used air from the face through cut chambers through block ventilation workings to the panel ventilation workings and further to the main ventilation workings, wherein part of the exhaust air from the panel ventilation workings through blocks in which cleaning operations are not carried out is recirculated to the block ventilation and cut workings, and also through block transport workings to the panel transport workings with the help of additional recirculation fan units located in the panel and block workings in which mining operations are not carried out.

[0005] The disadvantage of all the above methods is that they are designed for horizontally oriented working systems (in the horizontal plane). For vertically oriented working systems, with significant elevation differences, the developed technical solutions must be adapted and are not acceptable in the proposed version.

[0006] A known method for ventilation of underground mining of kimberlite pipe reserves is disclosed in RU Patent No. 2299988 (priority dated 06.12.2005, IPC E21F 1 / 00 ​​(2006.01), patent holder State Educational Institution of Higher Professional Education PEOPLES' FRIENDSHIP UNIVERSITY OF RUSSIA (RUDN University) (RU), published 05.27.2007, Bulletin No. 15), which includes driving vertical shafts, a spiral automobile inclination and connected capital and block workings. Ventilation wells are drilled in the upper part of the spiral automobile inclination to the ground surface, and raises are driven to the junction of the spiral automobile inclination and the block horizontal workings behind the ventilation wells. At the same time, between the place where the air jets exit from the spiral automobile slope into the ventilation wells and the risers, airlocks for sealing the spiral automobile slope are installed.The disadvantage of this method is that the developed solutions are only applicable for mining a section of the deposit directly adjacent to the quarry’s protective pillar (upper horizons of the mine).

[0007] The closest technical solution is a method of ventilation of underground mining of kimberlite pipe reserves using three vertical and one blind shafts, a spiral ramp (automobile slope), and development workings [Copies of S.V. Justification of fresh air flow rate for the lower horizons of the International mine of ALROSA (PJSC) / / Occupational Safety in Industry. 2024. No. 2. pp. 76-81. DOI: 10.24000 / 0409-2961-2024-2-76-81].To implement the method, a ventilation network calculation model is developed, air is supplied to the mine through the mine workings (ventilation) system using a main ventilation fan with separate ventilation of the upper and ultra-deep levels, the air flow is directed using ventilation structures, an auxiliary stationary main ventilation fan is installed on the surface on an auxiliary ventilation shaft for separate air supply to the upper levels, and air is supplied to the ultra-deep levels using additional mine fans with air exchange and reuse from existing reserves. Drawbacks of the prototype include the presence of a difficult-to-ventilate zone at the lower (deep) levels below -790 m. This results in difficulties in supplying fresh air to consumers at approximately -950 m and below.Another reason for ineffective ventilation is the recirculation of some of the air into the mine's ventilation network by installing sail-shaped ventilation structures on the junctions with ventilation risers and automatic ramps. These ventilation structures are ineffective if they obstruct the pressure differential between the incoming and outgoing air streams, which means the pressure within the workings is equalized and air movement is impeded. Above-ground placement of an auxiliary ventilation system requires additional resources to prepare the fresh air entering the mine for ventilation, especially in winter.

[0008] The technical problem solved by the invention is the effective ventilation of the lower horizons of an ultra-deep underground mine.

[0009] The technical result that allows solving this problem is the formation of a combined (common) aerodynamic network with two independent aerodynamic circuits (parts of the network).

[0010] The claimed method is explained by graphic materials, where Fig. 1 shows a general diagram of the ventilation organization, and Figs. 2-4 graphically present the main results obtained from modeling the operating modes of ventilation units.

[0011] List of items provided in the graphic materials:

[0012] 1 - skip shaft (SS);

[0013] 2 - cage shaft (KS);

[0014] 3 - ventilation and auxiliary trunk (VVS);

[0015] 4 - inclined ramp;

[0016] 5 - side of the "International" quarry;

[0017] 6 - blind skip shaft (BSS);

[0018] 7 - vertical risers (VV);

[0019] 8 - opening auto slope;

[0020] 9 - spiral ramp;

[0021] 10 - blind ventilation jumper;

[0022] 11 - ventilation airlock;

[0023] 12 - ventilation door with ventilation window;

[0024] 13 - main ventilation fan (MVF);

[0025] 14 - underground auxiliary stationary fan for main ventilation (PVSVGP);

[0026] 15 - mobile mine fan (PMF).

[0027] The method is as follows.

[0028] The mine field is opened by three shafts (SS-1, KS-2, VVS-3) and an inclined ramp 4, which goes into the side of the Internatsionalny quarry 5. The shafts are located on the flank of the mine field.

[0029] The length of SS 1 is 1030 meters. The shaft has conjugations with marks: +85 m, - 200 m, - 290 m, - 380 m, - 560 m, - 625 m.

[0030] The length of KS 2 is 1023 meters. The shaft has conjugations with marks: +85 m, -200 m, -290 m, -380 m, -560 m, -625 m, -611 m.

[0031] VVS 3 has conjugations with marks +85 m, +75 m, +54 m. The barrel length is 345 meters.

[0032] Preparation of the mine field - field, carried out by haulage workings at elevations of +85 m, - 200 m, - 380 m, - 560 m, - 790 m.

[0033] Preparation of mineral reserves for cleaning extraction is carried out using a network of spiral ramps 9 and haulage workings at elevations of +85 m, - 200 m, - 380 m, - 560 m, - 790 m. Spiral ramps 9, from which layered accesses are made, are used to outline the mineral resource.

[0034] Also, the SSS 6 complex is used for handling rock mass from the -790 m horizon, its depth is 447 meters.

[0035] To access reserves in the "super-deep" horizons (-820 m / -1250 m), it is planned to drive vertical raises 7, as well as a stripping truck slope 8 at elevations of -790 m / -950 m / -1050 m / -1250 m. Starting from the -950 m horizon and up to the -1250 m horizon, the route of the stripping truck slope 8 passes around the ore body (in a spiral). Truck slope 8 is driven at an angle of 8 ÷ 9 degrees. The production horizons with the necessary room-type service workings, as well as with connections with vertical raises 7, are located at elevations of -950 m, -1050 m and - 1250 m.

[0036] The method involves the use of ventilation devices and structures for positive (ventilation units) and negative regulation (ventilation doors and structures of various designs) of fresh air supplied for ventilation through the workings network and involves the joint operation of three groups of mine fans:

[0037] - surface fan of the main ventilation (VGP), with the recommended parameters of its operation (Fig. 2);

[0038] - underground auxiliary stationary fan for main ventilation (UAMFV), which must be in the mode of joint use with the VGP, in order to avoid the creation of a recirculation loop at the installation site (Fig. 3);

[0039] - two underground mobile mine fans (UMMF) installed in parallel. The optimal air flow rate (UMMF capacity) should not exceed the fresh air flow rate supplied to the PVSVGP at approximately -650 m (Fig. 4). The number of units depends on their aerodynamic characteristics.

[0040] Air supply to the mine is carried out during the simultaneous development of sub-quarry reserves, including the work zone under the protective quarry entirety (ceiling) at the upper elevations (upper horizons) and horizons of significant depth of occurrence of minerals down to the mark of -1000 m and below (ultra-deep horizons) through the system of (ventilation) mine workings with the help of VGP 13 with an independent ventilation mode of the upper (operational block (EB) No. 3 / 4) and ultra-deep horizons (EB No. 11-14), united by a common aerodynamic network.

[0041] To implement the proposed method, a calculation model of the mine ventilation network is developed for simulating air exchange processes during operations based on the AeroSet application, which includes a set of programs that organize the analytical process in a computing system using an integrated software development environment for Microsoft Windows in Delphi 7. Air is supplied to the mine through the system of (ventilation) workings using the combined operation of VGP 13, PVSVGP 14 and PShV 15 with separate ventilation of the upper, lower and ultra-deep horizons, but with the formation of a combined (common) aerodynamic network with two independent aerodynamic circuits (parts of the network). In this case, the VGP, PVSVGP and PShV operate in a combined operation mode with flow rates in the ratio of 0.95 ÷ 1.05 / 0.57 ÷ 0.63 / 0.5 ÷ 0.53.The fresh air flow entering the KS 2 shaft at the +85m elevation, connected to the shaft yard, is directed for the upper levels using ventilation structures 10 and 11. Two blind ventilation bulkheads (bulkhead 10) are installed on the VVS shaft and working 4, leading to the outlet at the open pit wall 5. A ventilation lock at the -145m elevation, installed on the spiral ramp, separates the outgoing air flow from the other ventilation components and finally forms an independent ventilation circuit for the upper levels. Used air from the upper level consumers (EB 3 / 4) enters the SS shaft at the +85m elevation.

[0042] The remaining fresh air is distributed through a second independent ventilation circuit to the lower and ultra-deep levels using the PVSVGP 14 unit in the main air supply heading for the lower level and mobile shaft fans 15 for the ultra-deep levels. Fresh air is supplied to the production units (EB 11, EB 12, EB 13 / 14) of the ultra-deep levels by installing a ventilation lock 11 in the transport heading at an elevation of -690 m and four ventilation doors 12 in the workings at the breaks of the opening auto-incline 8 with vertical raises 7 at elevations from -1050 m to -1250 m. The outgoing air stream is discharged through shaft SSS 6, spiral ramps, and then splits into sections at the -560 m, -380 m, -200 m horizons, and then to shaft SS 1 at the surface. Given the descending order of mining reserves EB 12 and EB 13 / 14, the outgoing air is sequentially connected to the vertical workings of shaft SSS 6 for the outgoing air stream.At each intersection, as the working front descends, at elevations from -1050 m to -1250 m, ventilation doors with adjustable openings (windows) 12 are installed. A group of ventilation doors 12 and airlock doors separate the outgoing and incoming air streams in parallel workings, eliminating their aerodynamic influence (in this case, by equalizing the pressure difference between the outgoing and incoming air streams). This allows for the organization, if necessary, of recirculating some of the air in workings EB11 and EB12 / 13 for reuse. The amount of air recirculated does not exceed the difference in flow rates between the main air supply working for the lower levels and the exhaust air collection point at the ultra-deep levels.

[0043] In the event of a reserve of fresh air in the form of leaks during its transportation to deep horizons, the method assumes the possibility, as needed, of organizing the supply of a portion of the air for reuse in the mine ventilation network by installing ventilation doors with adjustable openings (windows) 12 on the connections with the ventilation riser and automatic slope.

[0044] The amount of air directed into the mine ventilation network for re-ventilation should not exceed its flow rate (in the form of leaks) from the -625 m mark to the lower mark of the deep horizons.

[0045] The main results obtained from modeling the operating modes of ventilation units (operating points) are shown in graphic form. The graphs (Figs. 2-4) show extracts of the obtained values ​​of air flow rates and depressions from the developed model, applied to the aerodynamic characteristics of the adopted ventilation equipment during joint operation on the network. Their types and brands are also indicated here. Fig. 2 shows the operating mode of the VGP during joint operation on the network, Fig. 3 - the operating mode of the PVSVGP during joint operation on the network, Fig. 4 - the operating mode of the PShV (2 units), when installed in parallel during joint operation on the network. For efficient operation on the ventilation network, ventilation units with similar aerodynamic characteristics can be used.Optimization of the air distribution scheme in the mine ventilation network allows switching the operating mode of the main ventilation fan to the range with maximum efficiency (the most effective in terms of minimizing energy consumption and cost-effectiveness, Fig. 2), increasing the ventilation efficiency of the mining and driving faces, as well as other consumers of fresh air in the mine (shaft). Uncontrolled mixing of the outgoing air stream with the supplied fresh air is eliminated in the area of ​​​​ore body development under the security open pit, when the spiral ramp connects with the drainage system workings at the -145 m mark using the ventilation lock 11. Due to the multidirectional pressure distribution diagrams in parallel workings in the area of ​​​​the ore body opening by the 8 ramp, with the vertical raise workings (VR) system 7, the poorly ventilated zone formed below the -950 m mark is eliminated.The presence of explosives, in addition, performs the function of dividing the main stream of fresh air into separate parallel streams for separate ventilation of individual sections and faces at different elevations.

[0046] As a result of the method implementation, the amount of air supplied for ventilation to consumers at the +85 m mark increased from 65 m 3 / s up to 130 m 3 / s, that is, it doubled. At the 625 m mark, the amount of fresh air also increased on average by 1.6 times from 120 m 3 / s up to 196 m 3 / sec. The largest increase in air flow rate is typical for the -1250 m elevation. Here, the air flow rate through the workings network was 164 m 3 / s, that is, it increased by 4.7 times. Before the proposed measures, its quantity did not exceed 36 m 3 / With.

Claims

1. A method for ventilating ultra-deep horizons of an underground mine during the development of sub-quarry reserves of a kimberlite pipe, including the development of a calculation model of a ventilation network, supplying air to the mine through a system of ventilation mine workings using a main ventilation fan with separate ventilation of the upper and ultra-deep horizons, shaping the direction of the air stream using ventilation structures, installing an underground auxiliary stationary main ventilation fan in the main air supply working for the lower ultra-deep horizons, supplying air to the ultra-deep horizons using additional mine fans, characterized in that mobile mine fans are used as additional mine fans at the ultra-deep horizons, and negative control ventilation devices - ventilation doors - are used as ventilation structures,in this case, the operation of the main ventilation fan, the underground auxiliary stationary main ventilation fan and the mobile mine fans is carried out in the mode of joint operation with flow rates in the ratio of 0.95÷1.05 / 0.57÷0.63 / 0.5÷0.53, while the optimal amount of air supplied by the underground mobile fans at the collection point of exhaust air at ultra-deep horizons does not exceed the flow rate of fresh air of the underground auxiliary stationary fan supplied at the location of the main air supply working for the lower horizons.

2. The method according to paragraph 1, characterized in that the supply of a portion of the air for reuse into the mine ventilation network is regulated using negative control ventilation devices.

3. The method according to paragraph 2, characterized in that the amount of air sent for reuse does not exceed the difference in flow rates at the location of the main air supply for the lower horizons and at the location of collection of exhaust air at the ultra-deep horizons.

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