A method for recovering residual ore between columns under the condition of dry filling of two-side goaf

Abstract

This invention provides a method for recovering residual ore from inter-pillar mining under dry backfilling conditions in goaf areas, belonging to the field of mining residual ore recovery technology. The core technology of this invention is to release the already filled waste rock from one side of the stope to form a stable slope and simultaneously create a space for compensation against inter-pillar collapse. This invention requires less preparatory work; personnel operate in a small-section roadway space excavated within the footwall of the inter-pillar, ensuring excellent safety; no special cutting work is required, avoiding construction risks; ore is released along the natural slope, reducing ore dilution and loss rates; medium-deep holes penetrate both the surrounding rock and the ore body sequentially; during blasting, explosives are only loaded into the blast holes penetrating the ore body, effectively protecting the integrity of the main roadway roof and the surrounding rock on both sides; a top-down, retreating, step-by-step operation effectively controls the stability of the surrounding rock in the goaf area, achieving efficient connection between mining, extraction, and backfilling; flexible selection of the bottom structure of single-sided or double-sided electric scraper tracks can systematically solve key problems in the recovery of similar inter-pillar residual ore.

Description

Technical Field

[0001] This invention relates to the field of mine residual ore recovery technology, and more specifically, to a method for recovering residual ore from pillars under dry backfilling conditions in goaf areas on both sides. Background Technology

[0002] All mining operations face the problem of residual ore recovery. The types of residual ore are diverse, and recovery technologies and methods need to be tailored accordingly. In mines employing a "stopement-wall-stopement" layout, residual ore recovery from pillar-wall type residual ore is representative and prevalent in various types of mines. Different recovery schemes can be adopted for this type of residual ore. The safest and most reliable scheme is to perform high-quality roof cementing and backfilling on both sides of the stope to form a robust artificial support structure, and then recover the pillars.

[0003] Due to various reasons, some mines dry-fill the goaf with waste rock after the stope mining is completed. When it is necessary to recover the pillar residue, the two sides of the stope have not formed a cemented backfill body beforehand, which brings many problems to the recovery work, such as safety management and loss dilution rate control. Therefore, a method for recovering pillar residue under the condition of dry backfilling of the goaf on both sides is proposed. Summary of the Invention

[0004] The purpose of this invention is to address the problems raised in the existing background technology. To achieve the above-mentioned objective, this invention provides the following technical solution: a method for recovering residual ore from pillars under dry backfilling conditions in goaf areas on both sides. Corresponding to the middle of the pillar, within the footwall surrounding rock at a certain thickness interval from the footwall boundary of the vein, and consistent with the dip direction of the vein, an electric scraper road is constructed from bottom to top, either from the lower middle section transport road or raised a certain distance, so that the electric scraper road is connected to the upper middle section transport road, forming a production channel for pedestrians and ventilation.

[0005] As a preferred technical solution of the present invention, several rock drilling tunnels suitable for medium and deep hole construction are arranged perpendicular to the electric scraper track at appropriate intervals along the longitudinal direction of the electric scraper track.

[0006] As a preferred technical solution of the present invention, a single-sided high bucket bottom ore extraction structure is constructed based on the electric scraper track. The single-sided high bucket bottom ore extraction structure includes a bucket hole and a bucket neck. The upper opening of the bucket neck is split and perforated along the inclined direction of the electric scraper track to form an ore receiving bucket.

[0007] As a preferred technical solution of the present invention, several rows of fan-shaped medium-deep holes are constructed in the rock drilling tunnel, with the hole rows perpendicular to the direction of the vein strike.

[0008] As a preferred technical solution of the present invention, the waste rock already filled in the goaf area of ​​one side of the ore chamber is released by the ore receiving funnel, so that the waste rock forms a stable slope in the state of natural repose angle, and the collapse compensation space for the inter-pillar ore mining and the self-flowing ore release interface are constructed simultaneously.

[0009] As a preferred technical solution of the present invention, according to the width of the column, several rows of medium-deep holes are loaded with explosives in stages, and only the part of the blast hole that passes through the ore body is filled with explosives to carry out segmented blasting, and the ore is violently thrown into the compensation space.

[0010] As a preferred technical solution of the present invention, the medium-deep hole blasting is carried out in a step-by-step manner from top to bottom. After all the medium-deep holes in the first-level drilling tunnel are blasted, the ore is extracted through the electric scraper. After that, the next round of ore extraction is carried out until all the pillar ore is blasted and released.

[0011] As a preferred technical solution of the present invention, the release of waste rock in the goaf and the blasting and recovery of residual ore in the pillar are both carried out in a step-by-step manner from top to bottom. The step distance of each release is based on the ore falling requirements of the rock drilling tunnel of the first layer, which is achieved by adjusting the number of ore release funnels.

[0012] As a preferred technical solution of the present invention, if the ore from the final blasting is piled up on the bottom plate and fails to be thrown into the compensation space due to the large width of the inter-pillar, explosives are loaded into the bottom of the remaining unblasted deep holes to carry out throwing blasting; if the top pillar of the mining area can remain stable, a double-sided funnel electric scraper bottom ore extraction structure is adopted.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention has high safety: the preparation work is minimal, and the workers always work in small-section electric scraper tracks and rock drilling tunnels, without being threatened by large areas of exposed roof, thus significantly improving the safety of the operation; 2. The core difficulties solved by this invention are: by releasing waste rock on one side and leaving waste rock to form a stable slope according to the natural angle of repose, the two major bottleneck problems of preparing compensation space for blasting and controlling dilution of ore release losses are solved simultaneously. 3. The present invention simplifies the process: no special construction and cutting work is required, which reduces the amount of preparation work, avoids damage to the integrity of the columns caused by cutting work, and reduces construction safety risks; 4. The present invention has a low dilution rate: because the angle of the waste rock slope formed in advance is the natural angle of repose, it is in a critical stable state. Theoretically, the collapsed ore is released along the slope, which can avoid the mixing of waste rock and effectively control the dilution rate. At the same time, the ore can be released along the slope without any retention, thus fundamentally solving the problem of ore loss. 5. The main working channel (electric scraper track) of this invention has good stability: in medium-deep holes, only the upper ore body section is charged and blasted. After blasting, the electric scraper track can remain intact and stable, and continue to play the role of a safe passage and ventilation. 6. This invention has strong adaptability: the blasting parameters can be flexibly adjusted according to the width of the pillars and the stability of the ore body, and a single-sided or double-sided ore extraction structure can be selected to adapt to different field conditions; 7. The invention operates in an orderly manner: it adopts a top-down, step-by-step retreat operation, which can gradually control the state of the goaf, minimize the impact of the operation on the stability of the surrounding rock, and can also refill the mined area as needed, so as to achieve an orderly connection between "mining-extraction-filling". Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure provided by the present invention; Figure 2 This is a schematic diagram of the structure provided by the present invention; Figure 3 This is a structural schematic diagram provided for the present invention.

[0015] The image shows: 1. Lower middle section transport roadway; 2. Electric scraper roadway; 3. Upper middle section transport roadway; 4. Rock drilling level roadway; 5. Bucket tunnel; 6. Bucket neck; 7. Ore receiving funnel; 8. Medium-deep hole; 9. Waste rock backfill; 10. Compensation space. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention.

[0017] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely illustrates some embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that, in the absence of conflict, the embodiments and features and technical solutions in the embodiments of the present invention can be combined with each other. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0018] Example 1: A method for recovering residual ore from pillars under dry backfilling conditions in goaf areas on both sides. Corresponding to the middle of the pillar, in the footwall surrounding rock, at a certain thickness interval from the footwall boundary of the vein, and in the same direction of vein dip, an electric scraper road 2 is constructed from bottom to top from the lower middle section transport road 1 or raised a certain distance, so that the electric scraper road 2 is connected to the upper middle section transport road 3, forming a production channel for pedestrians and ventilation.

[0019] Several rock drilling tunnels 4 suitable for medium-deep hole construction are arranged at appropriate intervals along the longitudinal direction of the electric scraper track 2 and perpendicular to the electric scraper track 2.

[0020] Based on the electric scraper track 2, a single-sided high bucket bottom ore extraction structure project is constructed. The single-sided high bucket bottom ore extraction structure project includes a bucket hole 5 and a bucket neck 6. The upper opening of the bucket neck 6 is split and perforated along the inclined direction of the electric scraper track 2 to form an ore receiving bucket 7.

[0021] Inside the rock drilling tunnel 4, several rows of fan-shaped medium-deep holes 8 are constructed, with the hole faces perpendicular to the vein's strike direction.

[0022] Using the ore receiving funnel 7, the waste rock 9 that has been filled in the goaf of one side of the ore stope is released, and the remaining waste rock forms a stable slope in the state of natural repose angle, thus constructing the inter-pillar ore mining collapse compensation space 10 and the self-flowing ore release interface.

[0023] Based on the width of the column, several rows of medium-deep holes 8 are loaded with explosives in stages. Only the part of the blast hole that passes through the ore body is filled with explosives, and segmented blasting is carried out. The ore is violently thrown and falls into the compensation space 10.

[0024] The blasting of medium-deep holes 8 is carried out in a step-by-step manner from top to bottom. After all the medium-deep holes 8 within the first-level drilling tunnel 4 have been blasted, the ore is extracted through the electric scraper 2. After that, the next round of ore extraction is carried out until all the pillar ore is blasted and released.

[0025] If the ore body between pillars is intact and has flat boundaries, a single blast should not exceed two rows of blast holes, and the subsequent 2-3 rows should be recovered by single-row blasting.

[0026] The release of waste rock 9 in the goaf and the blasting and recovery of residual ore in the pillar are both carried out in a step-by-step manner from top to bottom. The step distance of each release is based on the ore falling requirements of the first-level drilling tunnel 4, which is achieved by adjusting the number of ore release funnels 7.

[0027] If the ore from the final blast is too wide and accumulates on the bottom plate and fails to be thrown into the compensation space 10, then explosives are loaded into the bottom of the remaining unblasted deep hole 8 for throwing blasting; if the top pillar of the mining area can remain stable, a double-sided funnel electric scraper bottom ore extraction structure is adopted.

[0028] Work Process: First, preliminary production channel construction work is carried out. Corresponding to the middle of the pillar, within the footwall surrounding rock at a certain thickness interval from the footwall boundary of the ore vein, and consistent with the dip direction of the ore vein, the electric scraper roadway 2 is constructed from bottom to top, starting from the lower middle section transport roadway 1 or raised a certain distance, so that the electric scraper roadway 2 can be smoothly connected with the upper middle section transport roadway 3, forming a complete production channel that can be used for pedestrians and ventilation. Next, along the longitudinal direction of the electric scraper roadway 2, at appropriate intervals, several drilling horizontal tunnels 4 suitable for medium and deep hole construction are laid perpendicular to the electric scraper roadway 2; at the same time, based on the electric scraper roadway 2, the single-sided high bucket bottom ore extraction structure project including the bucket tunnel 5 and the bucket neck 6 is constructed, and the upper opening of the bucket neck 6 is split along the dip direction of the electric scraper roadway 2 to form the ore receiving funnel 7.

[0029] After the passage and structural engineering is completed, several rows of fan-shaped medium-deep holes 8 are constructed in the drilling tunnel 4 to ensure that the hole faces are perpendicular to the vein strike direction. Subsequently, compensation space is constructed by using the receiving funnel 7 to release the waste rock 9 that has been filled in the goaf of one side of the stope, so that the waste rock 9 forms a stable slope at a natural angle of repose, thus constructing the inter-pillar ore recovery collapse compensation space 10 and the self-flowing ore release interface. The release of waste rock 9 in the goaf must be carried out in a step-by-step manner from top to bottom, with the step distance of each release being based on the ore falling requirements of the drilling tunnel 4 of the first layer, which is achieved by adjusting the number of receiving funnels 7.

[0030] After the compensation space is ready, the blasting operation begins. Based on the width of the pillar, explosives are loaded into several rows of medium-deep holes 8 in stages. Only the portion of the blast holes that penetrates the ore body is loaded with explosives, and segmented blasting is implemented to violently throw the ore into the compensation space 10. The ore blasting of the medium-deep holes 8 is carried out in a top-down, retreating step-by-step manner. After all the medium-deep holes 8 within the first-level drilling tunnel 4 have been blasted, the ore extraction operation is completed via the electric scraper track 2. If the ore body of the pillar is intact and has flat boundaries, a single blast is controlled within two rows of blast holes. The later 2-3 rows are then recovered using a single-row blasting method.

[0031] After a single level of ore extraction is completed, the next round of extraction for the corresponding level begins, and this cycle continues until all the ore in the pillar is blasted and released. During the operation, if the ore from the final blast accumulates on the bottom plate and fails to be thrown into the compensation space 10 due to the large width of the pillar, explosives can be loaded into the bottom of the remaining unblasted deep holes 8 for throwing blasting to complete the ore recovery. If the top pillar of the mining area can remain stable, a double-sided funnel electric scraper bottom ore extraction structure can be used to improve operational efficiency.

[0032] Example 2: A method for recovering residual ore from pillars under dry backfilling conditions in goaf areas on both sides. Corresponding to the middle of the pillar, a certain thickness is spaced between the lower wall rock and the lower wall boundary of the vein, and the dip direction of the vein is consistent with that of the vein. From the lower middle section transport road 1 or raised a certain distance, an electric scraper road 2 is constructed from bottom to top, which is connected to the upper middle section transport road 3 to form a production channel for pedestrians and ventilation. Several rock drilling tunnels suitable for medium-deep hole construction are arranged at appropriate intervals along the longitudinal direction of the electric scraper track and perpendicular to the electric scraper track.

[0033] Based on the electric scraper track, construct the ore extraction structure at the bottom of the single-sided high bucket (bucket passage 5, bucket neck 6). Split the upper opening of the bucket neck along the inclined direction of the electric scraper track to form the ore receiving bucket 7.

[0034] Inside the rock-drilling tunnel, several rows of fan-shaped medium-deep holes were constructed, with the hole faces perpendicular to the vein's strike direction.

[0035] Using the ore receiving funnel, the waste rock 9 that has been filled in the goaf of one side of the ore stope is released, forming a stable slope in the state of natural repose, and constructing the inter-pillar ore mining collapse compensation space 10 and the self-flowing ore release interface.

[0036] Based on the width of the columns, several rows of medium-deep holes are filled with explosives (only the upper part of the blast holes that penetrates the ore body is filled with explosives) and blasted in stages. The ore is violently thrown into the compensation space created in advance.

[0037] The medium-deep hole blasting is carried out in a step-by-step (multi-stage) manner from top to bottom. After all the medium-deep holes in the first-level drilling tunnel are blasted, the ore is extracted through the electric scraper. After that, the next round of ore extraction is carried out until all the pillar ore is blasted and released.

[0038] If the inter-pillar ore body is intact and has flat boundaries, a single blast should not exceed two rows of blast holes. In the later stages, the ore should be recovered by single-row blasting for the 2nd to 3rd rows.

[0039] The release of waste rock from the goaf and the blasting recovery of residual ore from pillars are both carried out in a step-by-step (multi-stage) manner from top to bottom. The distance of each release step is based on the ore falling requirements of the first-level drilling tunnel, and is achieved by adjusting the number of ore release funnels.

[0040] If, due to the large width of the pillars, the ore from the final blasting accumulates on the bottom plate and fails to be thrown into the compensation space, explosives can be loaded into the bottom of the remaining unblasted deep holes for blasting, maximizing ore recovery. If conditions permit and the project requires it, and the top pillars in the mining area can remain stable, a double-sided funnel electric scraper bottom ore extraction structure can be adopted, resulting in better control of the loss and dilution rate.

[0041] This invention features minimal preparatory work, allowing personnel to work within small cross-sections and low-lying tunnels throughout the entire production process, free from the threat of large-area exposed roofs, ensuring excellent safety. The invention utilizes the release of pre-filled waste rock from one side of the stope, creating a stable slope at a natural angle of repose for the ore to collapse into the pillar. The core technology of this invention, which compensates for space, cleverly solves key challenges in one fell swoop: it eliminates the need for specialized cutting work, simplifying preparatory work, omitting cutting processes, significantly reducing construction safety risks, and avoiding damage to the integrity of the pillar. During ore extraction, the collapsed ore is released along the natural slope formed by the remaining waste rock, theoretically preventing waste rock contamination and resulting in extremely low dilution rates. This also avoids the ore loss issues associated with "mixed ore and rock ore discharge" methods that could lead to excessive dilution. In this invention, deep holes penetrate both the surrounding rock and the ore body. During the main blasting, explosives are only loaded onto the portion of the borehole penetrating the ore body. After blasting, the electric scraper track remains intact and stable, continuously providing a safe passage and ventilation function, ensuring excellent on-site working conditions.

[0042] When blasted ore accumulates on the floor and fails to be thrown into the compensation space, the undamaged "rock holes" of this invention provide ideal conditions for violent throwing and transportation. This invention adopts a top-down, retreating, step-by-step (multi-stage) operation method, with waste rock being released gradually from the goaf, maximizing efficiency. This invention reduces the impact of production operations on the stability of the surrounding rock. When conditions permit, the upper area where previous mining has ended can also be promptly backfilled with waste rock, achieving an efficient and orderly connection between "mining-extraction-filling," which is beneficial for safety management and production organization.

[0043] The present invention allows for flexible selection of the bottom structure of the electric scraper track on one or both sides to meet the needs of different site conditions, and the solution is highly adaptable.

[0044] Working Principle: This invention is based on the core logic of "channel protection - space construction - precise blasting - orderly recovery". By constructing a safe operating channel and reasonable compensation space, combined with step-by-step blasting and orderly ore extraction, it achieves safe and efficient recovery of pillar residual ore in the dry-filled goaf on both sides. By constructing an electric scraper roadway 2 connecting the upper middle section transport roadway 3 and the lower middle section transport roadway 1 in the footwall surrounding rock, and laying a rock drilling horizontal roadway 4, an independent pedestrian, ventilation and operation channel system is constructed. The small cross-section tunnel space avoids the risk of large-area roof exposure, providing a basic guarantee for safe operation throughout the process. At the same time, based on the electric scraper roadway 2, a bottom ore extraction structure including a bucket tunnel 5, a bucket neck 6 and an ore receiving funnel 7 is constructed to ensure smooth ore extraction.

[0045] The core principle lies in the ingenious use of existing backfill waste rock to construct a compensation space: the backfill waste rock 9 on one side of the ore chamber is released through the ore receiving funnel 7, so that it forms a stable slope with a natural angle of repose, which serves as a compensation space 10 for the collapse of the inter-pillar ore. No additional construction or cutting work is required, which simplifies the process and avoids damaging the integrity of the inter-pillar.

[0046] During the blasting recovery stage, based on the directional blasting principle of the fan-shaped medium-deep holes 8, explosives are charged only on the upper ore body section of the blast hole. The blasting impact force propels the ore into the preset compensation space 10. A top-down, retreating, step-by-step operation is adopted, with the ore discharge step distance adjusted as needed, allowing for precise control of the blasting range and ore extraction rhythm, adapting to the recovery needs of columns of different widths. To address the ore accumulation problem in wide columns, secondary blasting is carried out using the retained medium-deep holes 8 to further ensure the recovery effect. When the top column is stable, a double-sided ore extraction structure is adopted, improving efficiency through symmetrical operation, ultimately achieving low-depletion, high-safety full recovery of residual ore from columns.

[0047] After the passage and structural engineering is completed, several rows of fan-shaped medium-deep holes 8 are constructed in the drilling tunnel 4 to ensure that the hole faces are perpendicular to the vein strike direction. Subsequently, compensation space is constructed by using the receiving funnel 7 to release the waste rock 9 that has been filled in the goaf of one side of the stope, so that the waste rock 9 forms a stable slope at a natural angle of repose, thus constructing the inter-pillar ore recovery collapse compensation space 10 and the self-flowing ore release interface. The release of waste rock 9 in the goaf must be carried out in a step-by-step manner from top to bottom, with the step distance of each release being based on the ore falling requirements of the drilling tunnel 4 of the first layer, which is achieved by adjusting the number of receiving funnels 7.

[0048] After releasing waste rock to create compensation space, the blasting operation begins. Based on the width of the pillar, explosives are loaded into several rows of medium-deep holes 8 in stages. Explosives are only loaded into the portion of the blast holes that penetrate the ore body at the top, implementing segmented blasting to force the ore to fall into the compensation space 10. The ore blasting of the medium-deep holes 8 is carried out in a top-down, retreating, step-by-step manner. After all the medium-deep holes 8 within the first-level drilling tunnel 4 have been blasted, the ore extraction is completed via the electric scraper track 2. If the ore body of the pillar is intact and has flat boundaries, a single blast is controlled within two rows of blast holes. The later 2-3 rows are then recovered using a single-row blasting method.

[0049] After a single level of ore extraction is completed, the next round of extraction for the corresponding level begins, and this cycle continues until all the ore in the pillar is blasted and released. During the operation, if the ore from the final blast accumulates on the bottom plate and fails to be thrown into the compensation space 10 due to the large width of the pillar, a small amount of explosives can be loaded at the bottom of the reserved deep hole 8 through the unblasted rock section to carry out a throwing blast to complete the ore recovery. If the top pillar of the mining area can remain stable, a double-sided funnel electric scraper bottom ore extraction structure can be adopted to improve operational efficiency.

[0050] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described herein. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present invention, as well as all technical solutions and improvements that do not depart from the spirit and scope of the invention, are covered within the scope of the claims of the present invention.

Claims

1. A method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas, characterized in that, Includes the following steps: In the middle of the corresponding column, within the surrounding rock of the lower plate, at a certain thickness interval from the boundary of the lower plate of the ore vein, and in the same direction as the dip of the ore vein, an electric scraper road (2) is constructed from the lower middle section transport road (1) or raised a certain distance, so that the electric scraper road (2) is connected to the upper middle section transport road (3), forming a production channel for pedestrians and ventilation.

2. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 1, characterized in that, Several rock drilling tunnels (4) suitable for medium-deep hole construction are laid out at appropriate intervals along the longitudinal direction of the electric scraper track (2) and perpendicular to the electric scraper track (2).

3. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 1, characterized in that, Based on the electric scraper track (2), a single-sided high bucket bottom ore extraction structure project is constructed. The single-sided high bucket bottom ore extraction structure project includes a bucket through (5) and a bucket neck (6). The upper opening of the bucket neck (6) is split along the inclined direction of the electric scraper track (2) to form an ore receiving bucket (7).

4. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 2, characterized in that, Inside the rock drilling tunnel (4), several rows of fan-shaped medium-deep holes (8) are constructed, with the hole rows perpendicular to the direction of the vein.

5. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 3, characterized in that, Using the ore receiving funnel (7), the waste rock (9) that has been filled in the goaf area of ​​one side of the ore chamber is released, so that the waste rock (9) forms a stable slope in the state of natural repose angle, and the inter-pillar ore mining collapse compensation space (10) and the self-flowing ore release interface are constructed simultaneously.

6. The method for recovering residual ore from pillars under dry backfilling conditions in goaf areas according to claim 4, characterized in that, According to the width of the column, several rows of medium-deep holes (8) are loaded with explosives in stages. Only the part of the blast hole that passes through the ore body is filled with explosives, and segmented blasting is carried out. The ore is violently thrown into the compensation space (10).

7. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 6, characterized in that, The blasting of medium-deep holes (8) is carried out in a step-by-step manner from top to bottom. After all the medium-deep holes (8) in the first-level rock drilling tunnel (4) are blasted, the ore is extracted through the electric scraper (2). After that, the next round of mining operations is carried out until all the inter-pillar ore is blasted and released.

8. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 5, characterized in that, The release of waste rock (9) from the goaf and the blasting and recovery of residual ore in the pillar are both carried out in a step-by-step manner from top to bottom. The step distance of each release is based on the ore falling requirements of the first-level drilling tunnel (4), and is achieved by adjusting the number of ore release funnels (7).

9. The method for recovering residual ore from pillars under dry backfilling conditions in goaf-side areas according to claim 6, characterized in that, If the ore from the final blast is piled up on the bottom plate and fails to be thrown into the compensation space (10) due to the large width of the inter-column, then an appropriate amount of explosives is loaded into the bottom of the remaining unblasted deep hole (8) to carry out throwing blasting and maximize ore recovery.

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