Deep hole lateral ore caving blasting method of low-unexploded firecracker

Abstract

The invention discloses a deep-hole lateral caving blasting method for low-blind blasting, and belongs to the technical field of mining. The method comprises the following steps: (1) determining hole net parameters; (2) blast hole arrangement; (3) preparing a medicine bag; (4) mounting a lower medicine bag; (5) filling an orifice cartridge bag; (6) setting a detonating cord of an orifice cartridge bag; and (7) connecting wires and detonating. The method can solve the blind shot problem in the deep hole lateral caving recovery process, and has the advantages of being reasonable in design, convenient to construct, high in efficiency, safe, reliable and capable of greatly reducing the safety risk of deep hole stope blasting recovery.

Description

Technical Field

[0001] The invention belongs to the technical field of mining, and in particular relates to a deep hole lateral mine collapse blasting method of a low blind blasting gun. Background Art

[0002] When using large-diameter deep-hole lateral caving and subsequent backfilling mining to recover the pillar stope, on the one hand, the ore rock itself has structures, fissures, caves and other channels; on the other hand, after being disturbed by the blasting of the first-step mine room stope, the degree of fragmentation is aggravated, and the ore rock structures, fissures, caves and other channels in the pillar stope are further expanded and connected, forming channels between blastholes, which are called "inter-hole channels"; in addition, there are cases where the pillars recovered after backfilling have single-sided or multi-sided backfill bodies, and there is an interface between the ore rock and the backfill body, which is called "rock-filling interface". The rock-filling interface is a weak structural surface. After being affected by blasting vibration or shock waves, the backfill body and the rock body are separated, and channels are also easily formed. The phenomenon of high-pressure wind rushing out from the side holes during the drilling construction process also confirms the existence of these channels, that is, the drilling encounters inter-hole channels such as fissures, caves or rock-filling interfaces, and the high-pressure wind rushes out from the side holes through the inter-hole channels.

[0003] According to the actual work and tests of deep hole lateral mine collapse blasting, in addition to general reasons such as the quality of blasting equipment and improper charging connection, the blasting energy or shock wave forms a blasting funnel or is released through the channels between holes, and the reflection stretching cuts off the detonating cords in the surrounding blast holes, destroying the charging structure of the surrounding blast holes, resulting in the collapse of the explosive packages (referred to as "explosive packages"), or the impact energy of the blast hole is cut off through the channels between holes and then the detonating cord of the blast hole is fired, resulting in blind shot problems such as interruption of explosion transmission, refusal of explosives to explode, and residual detonating cord at the hole mouth. Summary of the invention

[0004] In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a deep hole lateral mine collapse blasting method with low blind shot, which solves the blind shot problem encountered in the deep hole lateral mine collapse mining process. It has the advantages of reasonable design, convenient construction, high efficiency, safety and reliability, and can greatly reduce the safety risks of deep hole mining field blasting operations.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A low blind shot deep hole lateral caving blasting method comprises the following steps:

[0007] (1) Determine the hole network parameters: Determine the hole network parameters of deep hole lateral mine collapse blasting by the hole diameter;

[0008] (2) Setting of explosive charges in blastholes: According to the position and number of channels between holes, the blastholes are divided into multiple sections in the direction of hole depth, and one explosive charge is set for each section to form multiple explosive charges and set to be detonated in the same section to prevent stress waves from being reflected through the spatial channel and stretching to cut off the detonating cord in the hole, thereby blocking the explosion in the hole; for blastholes without exposed channels between holes, in order to prevent the possible influence of the spatial channel, one explosive charge is added for every 20m of the single hole charge length; for adjacent blastholes within 0.5m of the hole mouth and less than the minimum resistance line, the explosive filling length is adjusted in the direction of hole depth to reduce the charge density, so that the explosive charges of adjacent holes are arranged in an upper and lower staggered manner, and the detonators are set to be detonated in the same section to effectively prevent the explosive charges of adjacent blastholes from affecting each other within the range of the minimum resistance line, and also to avoid the formation of a dense area of ​​explosives that damages the explosion of surrounding holes; the side holes adjacent to the rock filling interface are adjusted to be in the same row as the main row of blastholes, and detonated in the same section to avoid the phenomenon of blind shots caused by the collapse of the first blast hole and the subsequent side hole;

[0009] (3) Preparation of explosive package: The explosive package is equipped with an electronic detonator bundled with a detonating cord;

[0010] (4) Installation of the lower charge: When charging, first install the cement plug, then use river sand or bamboo tubes to fill the emulsion explosives, use double detonating cords to transfer the explosion in the hole, and after filling to the position of the lower charge, use a lifting rope to lower the charge into place and fill with sand, and repeat the filling cycle upwards; the lower charge uses the charge prepared in step (3);

[0011] (5) Filling the orifice charge: When the charge is filled to the last layer, it is the orifice charge position. The orifice charge is set below the loose blasting resistance line, and the orifice sand filling length is 2.0-2.5m. The orifice charge is the charge prepared in step (3);

[0012] (6) Setting of the detonating cord of the hole charge: straighten the detonating cord that has been pulled out of the hole and insert it into the hole charge to form a two-way detonation method. Place the charge into the hole and fill it with sand to seal the hole.

[0013] (7) Connect and detonate: After the deep hole charging in the blasting area is completed, connect the wires in parallel with the electronic detonators and then connect them to the blasting busbar. Detonate after confirming that the area is cleared and the warning is in place.

[0014] Furthermore, in step (1), according to the rock mechanics of the mine and the crushing of the pillar ore and rock, the parameters of the deep hole lateral caving blasting hole network are determined to be 2.2m~2.5m×2.2m~2.5m by the φ110mm hole diameter.

[0015] Furthermore, in step (3), the method for making the explosive package includes the following steps: folding the detonating cord in half and overlapping it with the electronic detonator, clamping the electronic detonator in the middle of the detonating cord, tightening the overlapping part, inserting the electronic detonator bundled with the detonating cord into the emulsion explosive, and locating the electronic detonator bundled with the detonating cord in the center of the explosive package.

[0016] Furthermore, the detonating cord is a short detonating cord of 15-20 cm, and the emulsion explosive is an emulsion explosive of φ90 mm and 70 cm in length.

[0017] Furthermore, in step (4), the cement plug is a column-cone cement plug with an upper cylindrical body and a lower cone. A lifting ring is provided at the center of one end of the upper cylindrical surface. The column-cone cement plug is placed at a distance of 1m to 1.5m from the bottom of the hole. The iron wire at one end of the hole mouth is fixed on a wooden bar. The column-cone cement plug is used as a support for the charge in the deep hole, and then river sand or bamboo tubes are used to fill the explosives. The depth position of the charge interval in the hole is measured from the hole mouth. When the charge reaches the lower charge bag position, the charge bag is hooked with a lifting rope with a hook. After it is lowered into place, sand can be filled, and the filling cycle is repeated upwards.

[0018] Furthermore, the cylindrical part of the column-cone cement plug has a diameter of 90 mm and a length of 100 mm, and the cone part has a height of 50 mm.

[0019] Beneficial effects of the present invention:

[0020] The present invention adopts a scheme of detonating multiple charges in the same section to eliminate the influence of the inter-hole channels, bundles the electronic detonator and the short detonating cord in the charge to enhance the detonation energy, supports with a cement plug at the bottom of the hole and sets the lower charge according to the position and number of the inter-hole channels, sets the charge at the hole mouth below the loose blasting resistance line to eliminate the influence of the blasting funnel, and detonates the charge in both directions to eliminate the residual detonating cord at the hole mouth. According to many years of practice, the blind blasting problems such as residual detonating cord and residual explosives encountered in the process of deep hole lateral collapse mining in the inter-pillar mining field are greatly reduced. The present invention has the advantages of reasonable design, convenient construction, high efficiency, safety and reliability, and can greatly reduce the risks of mining and mining in deep hole mining fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 lay out the plan for the blastholes;

[0022] Figure 2 This is the layout diagram of multiple explosive charges being detonated in the same section;

[0023] Figure 3 This is a schematic diagram of the explosive package structure. The main component symbols in the figure are as follows: 1-electronic detonator, 2-short detonating cord, 3-emulsion explosive, 4-detonator leg wire, 5-lifting ring;

[0024] Figure 4 This is a schematic diagram of an electronic detonator bundled with a short detonating cord. The main component symbols in the figure are as follows: 1-electronic detonator, 2-short detonating cord, 4-detonator leg wire;

[0025] Figure 5 It is a schematic diagram of the column-cone cement plug structure, and the main component symbols in the figure are as follows: 6-cylinder, 7-cone, 8-lifting ring;

[0026] Figure 6 This is a schematic diagram of the spaced charge structure;

[0027] Figure 7 Schematic diagram of the orifice drug package setting. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0029] At present, the pillars of Panlong Lead-Zinc Mine adopt large-diameter deep hole lateral ore collapse and subsequent filling mining method for retreat mining. The width of the mining field is within 12m. A KQG-100 high-pressure annular down-the-hole drill is used to construct a deep hole of 40 to 50 meters downward in the upper chamber of the mining field, with a hole diameter of 110mm. After the top is broken to form a cutting vertical groove, the whole hole is lateral blasted and retreated. A remote-controlled scraper is used to mine at the bottom of the mining field. Lateral ore collapse and mining are operated alternately. After the mining of the mining field is completed, filling is carried out. There are various blind shot problems described in the background technology. According to the continuous testing, analysis and improvement of the deep hole lateral ore collapse blasting in the pillar mining field of Panlong Lead-Zinc Mine, the research team has taken corresponding measures and formed a matching mature and stable innovative technology after long-term testing, providing a deep hole lateral ore collapse blasting method with low blind shot. The specific operation steps are shown in the embodiment.

[0030] Example

[0031] Step 1: Determine the parameters of the large-diameter deep hole lateral blasting hole network

[0032] According to the rock mechanics of the mine and the crushing of the pillar ore, the mesh parameters are determined to be 2.2m~2.5m×2.2m~2.5m by the φ110mm aperture, such as Figure 1 As shown, the green grid is the mesh line, and the mesh parameter is 2.3m.

[0033] Step 2: Blast hole charge setting

[0034] 1. Multiple explosive packs in the hole are detonated at the same stage to eliminate the influence of channels between holes

[0035] Due to the broken structure of the pillar ore rock, there are fissure channels and other inter-hole channels, so the corresponding depth position should be recorded during drilling. In order to divide the blasthole into multiple sections in the depth direction according to the position and number of inter-hole channels. A charge is set at the upper end of each section to form multiple charges and set the same section to detonate, so as to prevent the stress wave from reflecting through the inter-hole channel, stretching and cutting the detonating cord in the hole, and blocking the explosion in the hole. Figure 2As shown in the figure, the 3-17C hole of the 7th blasting of the 720 pillar mining area of ​​Panlong Lead-Zinc Mine has a cave fissure at 15.6m to 16.8m, and the 4-17 hole has a cave fissure at 15.3m to 16.9m. The cave fissures of the two adjacent holes are connected to form an inter-hole channel. Therefore, the design uses the cave position as the dividing point to divide the blasthole into two sections, upper and lower. The lower charge of the 3-17C hole is set at 19.1~17.7m, and the upper charge is set at 12.7m~11.3m. The lower charge of the 4-17 hole is set at a depth of 18.7m~17.3m, and the upper charge is set at 3.2~1.8m at the hole mouth. For the blastholes that do not reveal the inter-hole channel, in order to prevent the possible influence of the inter-hole channel, one charge is added for every 20m of the single hole charge length.

[0036] 2. Displacement of explosive charges and detonation in the same section eliminates the influence of adjacent holes

[0037] For adjacent blastholes within 0.5m of the hole mouth and less than the minimum resistance line, adjust the charge range in the direction of the hole depth to stagger the charge packs and reduce the charge density; detonate at the same time and in the same section to effectively prevent the charge packs of adjacent blastholes from affecting each other and avoid the formation of explosive-intensive areas that cause explosion damage to surrounding holes, such as Figure 2 shown.

[0038] 3. Arrange adjacent side holes in the same row and detonate in the same section to eliminate the influence of rock filling interface

[0039] Blind shots often occur in the side holes near the rock-fill interface. The main reason is that the side holes in the pillar stope are close to the rock-fill interface and are not as stable as continuous entities. There is a phenomenon that the first hole collapses directly into the side holes in the undetonated area, resulting in blind shots. Therefore, the spacing between the side holes is set to be consistent with that of the normal holes, so that the side holes and normal holes are arranged on the same straight line, such as Figure 1 As shown, the side holes are charged according to the smooth blasting parameter requirements, and the side holes and adjacent holes in the same row are set to the same section to avoid the phenomenon of blind shots caused by the first blast hole collapsing and then the side hole blasting.

[0040] Step 3: Making medicine bags

[0041] like Figure 3 and Figure 4As shown, a single-shot electronic detonator 1 and a short detonating cord 2 are bundled in the explosive package to enhance the detonation energy. Before charging, prepare a short detonating cord 2 of 15 cm to 20 cm / piece according to the number of explosive packages, fold the short detonating cord 2 in half and overlap the open end with the electronic detonator 1, sandwich the electronic detonator 1 in the middle, and wrap the overlapping part tightly with electrical tape. Insert a bamboo stick into the middle part of a section of φ90 mm emulsion explosive 3 about 70 cm long and pull it out to form a hole, then insert the electronic detonator 1 bundled with the short detonating cord 2 into the hole, ensure that the electronic detonator 1 and the short detonating cord 2 are in the center of the explosive package, straighten the detonator foot line 4, and then use wide transparent glue to wrap the position of the electronic detonator 1 inserted with the short detonating cord 2 to ensure that the electronic detonator 1 and the detonator foot line 4 will not fall off, and a hanging ring 5 is provided on the top of the explosive package. The electronic detonator 1 and the short detonating cord 2 bundled in the explosive bag can enhance the detonation energy and improve the detonation reliability during detonation.

[0042] Step 4: Filling the lower medicine bag

[0043] According to the location and number of the inter-hole channels in the blasthole catalog, fill the lower charge bag, which is the charge bag prepared in the third step. When filling the charge, first install the column-cone cement plug. Figure 5 As shown, the upper part of the column-cone cement plug is a cylinder 6, and the lower part is a cone 7 for easy lowering. The column-cone cement plug is made before charging, the diameter of the cylinder part is 90mm, the length is 100mm, the height of the cone part is 50mm, and a lifting ring 8 is set at the center of one end of the upper cylindrical surface of the cylinder 6. Figure 6 As shown, an iron wire is bolted to the lifting ring 8, and the column-cone cement plug is placed at a distance of 1m to 1.5m from the bottom of the hole. The iron wire at one end of the hole mouth is bolted to a wooden strip to fix it. The column-cone cement plug serves as a support for the charge in the deep hole. River sand or bamboo tubes are used to space the charge in the hole, and double detonating cords are used for detonation transmission. The detonating cords should be laid from the position of the cement plug at the bottom of the hole to the hole mouth, and should be 1.5m longer than the hole mouth. The specific method is to bolt two detonating cords of the same length to the lifting ring of the emulsion explosive in parallel and insert them into the emulsion explosive when lowering the first emulsion explosive. The emulsion explosive with the detonating cord is lowered to the bottom of the hole with a lifting rope, and the extra detonating cord at the hole mouth is temporarily fixed to the wooden strip. As shown in FIG. Figure 6As shown, the depth position of the interval charge in the hole is measured from the hole mouth as the starting point of the depth measurement, and then river sand or bamboo tube interval charge is used to fill the charge according to the designed hole interval charge structure parameters. The interval charge structure parameters list the structure, interval position and charge position of each blast hole charge. Generally, the blast hole is structured with 1 to 3 φ90mm emulsion explosives and 1.5 to 1.8m river sand, and the side hole is structured with one φ90mm emulsion explosive and 1.0 to 1.3m bamboo tube. The interval position and charge position are determined by measuring rope. When the charge reaches the lower charge position, the hooked lifting rope is used to hook the lifting ring 5 of the charge to lower the charge into the hole. The lowering process needs to be coordinated with the straightening of the detonator foot line of the charge, and the detonator foot line is fixed on the wooden strip at the hole mouth. After the lifting rope is pulled out, sand can be filled, and the filling is repeated upwards.

[0044] Step 5: Filling the orifice bag

[0045] The orifice charge is located below the loose blasting resistance line to eliminate the influence of the blasting funnel.

[0046] When the explosives are filled to the last layer, it is the position of the hole mouth charge, and the hole mouth charge adopts the charge made in the third step. Because the charge is shallow, when the selected resistance line is small, it is easy to form a larger blasting funnel radius, ore rock throwing or dislocation, resulting in the collapse of ore rock in the hole mouth blasting funnel area, destroying the rock layer at the rear side of the hole charge, or causing the ore rock to shift and cut off the detonating cord of the adjacent hole to block the transmission of explosion, or causing ore rock throwing to interrupt the surrounding detonating line. Therefore, when charging, the charge set at the hole mouth should be appropriately buried deeper, and the vertical resistance line should be reasonably adjusted to reduce the influence range of the blasting funnel, avoid the throwing blasting phenomenon, and effectively eliminate the occurrence of ore rock throwing or displacement. According to the field test, the explosive charge is set below the loose blasting resistance line. The specific measures are to appropriately increase the hole filling length, about 1.5m to 2.5m, which can effectively prevent the blasting funnel formed by the blasting of the first blast hole from shaking off or collapsing the explosive charge of the surrounding subsequent blast holes, prevent the dislocation of the ore and rock from cutting off the detonating cord of the rear hole and blocking the explosion transmission, and also effectively eliminate the phenomenon of blasting waste rock interrupting the surrounding detonating lines, such as Figure 7 shown.

[0047] Step 6: Hole-mouth charge detonating cord setting

[0048] The orifice charge is set to detonate in both directions to eliminate residual detonating cord.

[0049] In the early stage of deep hole blasting, one or two meters of detonating cord often remain at the cut-out. This is the undetonated part of the detonating cord at the tail of the hole mouth charge that is bundled and plugged into the hole mouth. After analyzing the cause of the residual short detonating cord, the present invention straightens the hole mouth detonating cord and reversely inserts it into the hole mouth charge into the hole and fills the hole with sand to seal it. Figure 6This method forms a two-way detonation mode for the hole-mouth detonating cord, which enhances the reliability of the detonation and transmission of the explosive pack and the detonating cord; it also reduces the impact force of the shock wave on the detonating cord, so that the detonating cord in the tail will not be washed away.

[0050] Step 7: Connect and confirm clearing alert before detonating

[0051] After the deep hole charging in the blasting area is completed, the electronic detonators are connected in parallel and then connected to the blasting bus. The personnel are evacuated to a safe area and the detonation is carried out after the area is cleared and the warning is issued.

[0052] Through the mutual coordination of the above steps of the present invention, according to years of practice, the blind shot problems such as residual detonating cord and residual explosives encountered in the deep hole lateral caving mining process of the pillar mining area are greatly reduced.

[0053] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the definition of the claims.

Claims

1. A deep hole lateral caving blasting method with low blind blasting, characterized in that: The steps include: (1) Determine the hole network parameters: Determine the hole network parameters of deep hole lateral mine collapse blasting by the hole diameter; (2) Setting of explosive charges in blastholes: according to the location and number of channels between holes, blastholes are divided into multiple sections and multiple explosive charges are set for detonation in the same section. For adjacent blastholes within 0.5 m from the hole mouth and less than the minimum resistance line, the charging range is adjusted in the direction of the hole depth, the explosive charges are arranged in a staggered manner, and the explosions are detonated in the same section. The side holes near the rock filling interface are adjusted to be in the same row as the main row of blastholes, and the explosions are detonated in the same section. (3) Preparation of explosive package: The explosive package is equipped with an electronic detonator bundled with a detonating cord; (4) Installation of the lower charge: When charging, first install the cement plug, then use river sand or bamboo tubes to fill the emulsion explosives, and use double detonating cords to transmit the explosion in the hole. After filling to the position of the lower charge, lower the charge and then fill with sand, and repeat the cycle upwards; (5) Filling of orifice charge: When the charge is filled to the last layer, it is the orifice charge position. The orifice charge is set below the loose blasting resistance line, and the length of the orifice sand filling is 2.0-2.5m; (6) Setting of the detonating cord of the hole charge: straighten the detonating cord that has been pulled out of the hole and insert it into the hole charge to form a two-way detonation method. Place the charge into the hole and fill it with sand to seal the hole. (7) Connect and detonate: After the deep hole charging in the blasting area is completed, connect the wires in parallel with the electronic detonators and then connect them to the blasting busbar. Detonate after confirming that the area is cleared and the warning is in place.

2. A low blind blasting deep hole lateral ore collapse blasting method as claimed in claim 1, characterized in that: In step (1), the parameters of the deep hole lateral mine collapse blasting network are determined to be 2.2m~2.5m×2.2m~2.5m by the φ110mm hole diameter.

3. A deep hole lateral mine collapse blasting method with low blind blasting as claimed in claim 1, characterized in that: In step (2), the blasthole is divided into multiple sections and multiple explosive packages are set for detonation in the same section. Specifically, according to the position and number of the channels between the holes, the blasthole is divided into multiple sections in the depth direction of the hole, and one explosive package is set for each section to form multiple explosive packages and set for detonation in the same section. For blastholes where the channels between the holes are not exposed, one explosive package is added for every 20m of the single-hole charging length.

4. A low blind blasting deep hole lateral caving blasting method as claimed in claim 1, characterized in that: In step (3), the method for making the explosive package includes the following steps: folding the detonating cord in half and overlapping it with the electronic detonator, clamping the electronic detonator in the middle of the detonating cord, wrapping the overlapping part tightly with tape, inserting the electronic detonator bundled with the detonating cord into the emulsion explosive, and placing the electronic detonator bundled with the detonating cord in the center of the explosive package.

5. A low blind blasting deep hole lateral caving blasting method as claimed in claim 4, characterized in that: The detonating cord is a short detonating cord of 15-20 cm, and the emulsion explosive is an emulsion explosive of φ90 mm and 70 cm in length.

6. A low blind blasting deep hole lateral caving blasting method as claimed in claim 1, characterized in that: In step (4), the cement plug is a column-cone cement plug with an upper cylinder and a lower cone. A lifting ring is provided at the center of one end of the upper cylindrical surface. The column-cone cement plug is placed at a distance of 1m to 1.5m from the bottom of the hole. The iron wire at one end of the hole mouth is fixed on a wooden bar. The column-cone cement plug serves as a support for the charge in the deep hole. Then, river sand or bamboo tubes are used to fill the emulsion explosive. When the charge reaches the position of the lower medicine bag, a lifting rope with a hook is used to hook the medicine bag. After it is lowered into place, sand can be filled. The filling cycle is repeated upwards.

7. A low blind blasting deep hole lateral caving blasting method as claimed in claim 6, characterized in that: The cylindrical part of the column-cone cement plug has a diameter of 90 mm and a length of 100 mm, and the cone part has a height of 50 mm.

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