Method for judging ore removal rate of sill-pillar-free sublevel caving mining method

Abstract

The invention belongs to the technical field of mining, and particularly discloses an ore removal rate judgment method of a sill-pillar-free sublevel caving mining method, which comprises the following steps: after blasting is completed, firstly calculating a predicted ore removal rate, then calculating an actually measured ore removal rate, then determining an actual ore removal amount, calculating an actual ore removal rate through the actual ore removal amount, and finally judging the ore removal rate of the sill-pillar-free sublevel caving mining method. When the actual ore removal rate is higher than or equal to the actually measured ore removal rate, the ore removal rate requirement is met, and when the actual ore removal rate is lower than the actually measured ore removal rate, the ore removal rate requirement is not met, and the mining scheme needs to be optimized again. The method aims at solving the problems that in the current mining process, ore removal time cannot be accurately stopped, the grade of ore is lowered, and the recovery rate is low. According to the method, the predicted ore removal rate is calculated by predicting the single caving amount, and finally the actual ore removal amount and the actual ore removal rate are determined by utilizing the shoveling ore removal amount and the shoveling position, so that the situation that waste rock is mixed into ore and the ore grade is reduced due to blind increase of the ore removal amount is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a method for judging the ore production rate of a bottom-pillar-free sublevel caving mining method. Background Art

[0002] The pillarless segmented caving mining method is an underground mining method that divides the ore body into several segments. There is no bottom structure in each segment. Instead, rock drilling and blasting are carried out in the approach route, allowing the ore to flow naturally to the mine exit tunnel with the help of gravity during the caving process, and then the ore is transported out with equipment such as shovel loaders. This method has the advantages of high mining efficiency, low safety and strong adaptability.

[0003] In the process of using the pillarless segmented caving mining method, it is necessary to reasonably divide the segment height according to factors such as the thickness and inclination of the ore body, and arrange the approach within the segment. At the same time, medium-deep hole or deep hole drilling is used to control the blasting parameters to achieve reasonable caving of the ore, and mining is carried out after the caving is completed.

[0004] However, in the current mining process using the pillarless staged caving mining method, mining decisions are mainly made based on manual experience. Therefore, it is impossible to accurately stop the mining time, the mining volume increases blindly, and the quality control of mining is ignored. A large amount of waste rock is mixed with the ore, which reduces the grade of the ore, causes ore depletion and loss, and leads to a low mining rate. Summary of the invention

[0005] The purpose of the present invention is to provide a method for judging the ore production rate of a pillarless step-down caving mining method, so as to solve the problem that in the current mining process, the ore production time cannot be accurately stopped, the grade of the ore decreases, the ore is depleted and lost, and the ore production rate is low.

[0006] To achieve the above object, the basic scheme provided by the present invention is: a method for determining the ore yield of a pillarless sublevel caving mining method, comprising the following steps:

[0007] S1. After the blasting is completed, the single collapse volume is measured and predicted, and the ore production rate is calculated by predicting the single collapse volume;

[0008] S2. Calculate the actual ore yield by measuring the opening distance of the eyebrow line;

[0009] S3. When the measured ore-producing rate is lower than the predicted ore-producing rate, it does not meet the ore-producing rate requirement and the mining plan needs to be re-optimized; when the measured ore-producing rate is higher than or equal to the predicted ore-producing rate, it meets the ore-producing rate requirement and the ore is shoveled out;

[0010] S4, determine the actual ore output by the shoveled ore output, and then calculate the actual ore output rate by the actual ore output;

[0011] S5. When the actual ore output rate is higher than or equal to the measured ore output rate, it meets the ore output rate requirements and mining is carried out according to the current mining plan; when the actual ore output rate is lower than the measured ore output rate, it does not meet the ore output rate requirements and the mining plan needs to be optimized.

[0012] The beneficial effect of the present invention is that the predicted mining rate is calculated by predicting the single collapse volume, which provides a preliminary theoretical basis for mining decision-making, no longer relying on manual experience, and further starting from the actual mine structure parameters, and mutually verifying with the predicted mining rate, thereby improving the accuracy of mining rate judgment. Finally, the actual mining volume and actual mining rate are determined by using the shoveled ore volume and shovel position, which can accurately grasp the situation of each specific mining location. If it does not meet the actual mining rate requirements, the mining plan is optimized, which helps to adjust the mining strategy in time to avoid the mixing of waste rock into ore and reduce the ore grade due to the blind increase in mining volume.

[0013] Scheme 2, which is the preferred basic scheme, in S1, the predicted single collapse volume is calculated by the following formula:

[0014] Q=V×T×R

[0015] In the formula: Q is the predicted single collapse volume; V is the volume of the ore body; T is the specific gravity of the ore body, and T is fixed at 4.12; R is the spatial position coefficient, which indicates the proportion of the useful mineral content in the ore to the total, and R is taken as 0.3, 0.6, and 1.0; the single collapse volume is predicted by calculating the formula to provide the predicted collapse volume for subsequent mining.

[0016] Option three is the preferred option of option two. The spatial position coefficient is selected based on the following criteria: when the content of useful minerals in the ore accounts for ≤30% of the total content, the spatial position coefficient R is 0.3; when the content of useful minerals in the ore accounts for 30% to 60% of the total content, the spatial position coefficient R is 0.6; when the content of useful minerals in the ore accounts for ≥60% of the total content, the spatial position coefficient R is 1.0; this allows the spatial position coefficient to be determined more accurately in practical applications, avoiding the arbitrariness of the value.

[0017] Scheme 4 is the preferred option of the basic scheme. In S1, the predicted ore recovery rate of the strip ore body and the ellipsoidal ore body is calculated by the following formula:

[0018] Z=Q×G

[0019] In the formula: Z is the predicted ore recovery rate; Q is the predicted single collapse volume; G is the ore body ratio, the G of the first layer of the strip ore body is 30%, and the G of the second layer of the strip ore body is 60%; the G of the first layer of the ellipsoidal ore body is 30%, and the G of the second layer of the ellipsoidal ore body is 60%, and the G of the ellipsoidal ore body greater than three layers is 100%;.

[0020] Scheme 5: This is the optimal choice of the basic scheme. In S2, the measured ore recovery rate of the strip ore body and the ellipsoidal ore body is calculated by the following formula:

[0021] W=L×M

[0022] Where: W is the measured ore recovery rate; L is the opening distance of the eyebrow line; M is the loose coefficient, M of the first layer of the strip-shaped ore body is 0.2, and M of the second layer is 0.5; M of the first layer of the ellipsoidal ore body is 0.3, M of the second layer is 0.6, and M of more than three layers is 0.6.

[0023] Option six, which is a preferred option of the basic option, in S2, the eyebrow opening distance is measured by an infrared rangefinder; using an infrared rangefinder to measure the eyebrow opening distance is convenient for non-contact measurement.

[0024] Option seven is the preferred basic option. In S4, a hydraulic dynamic metering device is installed on the bucket of the scraper, and the actual output of the ore is determined by transmitting the data to the central control system through the on-board computer and wireless network.

[0025] Scheme 8, which is the preferred basic scheme, in S4, the actual ore production rate is calculated by the following formula:

[0026] K=J / F×100%

[0027] Where: K is the actual ore output rate; J is the actual single collapse volume; F is the actual ore output. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention discloses a flow chart of a method for determining the ore yield of a pillarless sublevel caving mining method. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below through specific embodiments:

[0030] A method for determining the ore yield of a pillarless sublevel caving mining method comprises the following steps:

[0031] S1. After the blasting is completed, the single collapse volume is calculated and predicted. The single collapse volume is calculated by the following formula:

[0032] Q=V×T×R

[0033] Where: Q is the predicted single collapse volume; V is the ore body volume; T is the ore body specific gravity, T is fixed at 4.12; R is the spatial position coefficient, indicating the proportion of useful mineral content in the ore to the total, R is 0.3, 0.6, 1.0.

[0034] The basis for selecting the spatial position coefficient is as follows: when the content of useful minerals in the ore accounts for ≤30% of the total proportion, the spatial position coefficient R is 0.3; when the content of useful minerals in the ore accounts for 30% to 60% of the total proportion, the spatial position coefficient R is 0.6; when the content of useful minerals in the ore accounts for ≥60% of the total proportion, the spatial position coefficient R is 1.0.

[0035] The predicted ore recovery rate is calculated by predicting the single collapse volume. The predicted ore recovery rate of banded ore bodies and ellipsoidal ore bodies is calculated by the following formula:

[0036] Z=Q×G

[0037] Where: Z is the predicted ore yield; Q is the predicted single collapse volume; G is the ore body ratio, the first layer G of the strip ore body is 30%, the second layer G of the strip ore body is 60%; the first layer G of the ellipsoidal ore body is 30%, the second layer G of the ellipsoidal ore body is 60%, and the ellipsoidal ore body is greater than three layers G is 100%;

[0038] S2. Use an infrared rangefinder to measure the opening distance of the eyebrow line and calculate the measured ore recovery rate. The measured ore recovery rate of the strip ore body and the ellipsoid ore body is calculated by the following formula:

[0039] W=L×M

[0040] Where: W is the measured ore extraction rate; L is the opening distance of the eyebrow line; M is the loose coefficient, M of the first layer of the strip ore body is 0.2, and M of the second layer is 0.5; M of the first layer of the ellipsoidal ore body is 0.3, M of the second layer is 0.6, and M of more than three layers is 0.6;

[0041] S3. When the measured ore-producing rate is lower than the predicted ore-producing rate, it does not meet the ore-producing rate requirement and the mining plan needs to be re-optimized; when the measured ore-producing rate is higher than or equal to the predicted ore-producing rate, it meets the ore-producing rate requirement and the ore is shoveled out;

[0042] S4. Install a hydraulic dynamic metering device on the bucket of the scraper, transmit the data to the central control system through the on-board computer and wireless network, determine the actual ore output, and then calculate the actual ore output rate. The actual ore output rate is calculated by the following formula:

[0043] K=J / F×100%

[0044] Where: K is the actual ore output rate; J is the actual single caving volume; F is the actual ore output;

[0045] The actual ore-discharging rate is calculated by the following formula:

[0046] K=J / F×100%

[0047] Where: K is the actual ore output rate; J is the actual single caving volume; F is the actual ore output;

[0048] S5. When the actual ore output rate is higher than or equal to the measured ore output rate, it meets the ore output rate requirements and mining is carried out according to the current mining plan; when the actual ore output rate is lower than the measured ore output rate, it does not meet the ore output rate requirements and the mining plan needs to be optimized.

[0049] The optimization of the mining plan is to optimize the layout of the upward fan-shaped medium and deep holes and the blasting charges:

[0050] Optimization of upward fan-shaped medium-deep holes: 1. Reconfirm the height from the tunnel bottom before designing the medium-deep holes; 2. Re-adjust the bottom distance of each row of holes, and the optimized bottom distance of the holes is equal to the original bottom distance × 0.8; 3. Take the drilling center determined in the drilling tunnel as the starting point to make a radial arrangement, first optimize the arrangement of the side hole angles, the optimized side hole angle is equal to the original side hole angle × 1.2, and then evenly arrange the remaining blast holes according to the adjusted hole spacing; 4. Evenly and staggeredly arrange the blast holes between adjacent rows to make the stress distribution reasonable.

[0051] Optimization of blasting charges: 1. Use blasting charges in the same row and section to increase the amount of charge per shot. 2. Use blasting charges in different sections of the same row. The optimized blasting volume is equal to the original blasting volume × 1.5. 3. Control the design shape of the blasting boundary and leave a gap at the boundary.

[0052] Table 1 Comparison between actual ore production rate and predicted ore production rate

[0053]

[0054] In Table 1, the predicted ore output rate is a known process parameter. The actual ore output is automatically measured and counted by the shovel loader and uploaded to the report. After manual review, the actual ore output rate is calculated. The mining level refers to the vertical distance between the upper and lower interfaces of the mining level, and the ore output point refers to the specific location where the ore body is mined.

[0055] By implementing the above method, it can be obtained that by predicting the amount of collapsed ore, counting the mined ore and analyzing the opening distance of the eyebrow line, the ore output rate of the mining face can be accurately determined, and the ore output control problem of the pillarless segmented caving mining method can be effectively controlled and solved, thereby improving the underground mining efficiency, increasing the ore output rate by 2-5%, and creating an economic benefit of 72,000 yuan / ton.

[0056] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for determining the ore yield of a pillarless sublevel caving mining method, characterized in that: The following steps are involved: S1. After the blasting is completed, the single collapse volume is measured and predicted, and the ore production rate is calculated by predicting the single collapse volume; S2. Calculate the measured ore yield by measuring the opening distance of the eyebrow line; S3. When the measured ore-producing rate is lower than the predicted ore-producing rate, it does not meet the ore-producing rate requirement and the mining plan needs to be re-optimized; when the measured ore-producing rate is higher than or equal to the predicted ore-producing rate, it meets the ore-producing rate requirement and the ore is shoveled out; S4, determine the actual ore output by the shoveled ore output, and then calculate the actual ore output rate by the actual ore output; S5. When the actual ore output rate is higher than or equal to the measured ore output rate, it meets the ore output rate requirements and mining is carried out according to the current mining plan; when the actual ore output rate is lower than the measured ore output rate, it does not meet the ore output rate requirements and the mining plan needs to be optimized.

2. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S1, the predicted single collapse amount is calculated by the following formula: Q=V×T×R Where: Q is the predicted single collapse volume; V is the ore body volume; T is the ore body specific gravity, T is fixed at 4.12; R is the spatial position coefficient, indicating the proportion of useful mineral content in the ore to the total, R is 0.3, 0.6, 1.

0.

3. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 2, characterized in that: The basis for selecting the spatial position coefficient is as follows: when the content of useful minerals in the ore accounts for ≤30% of the total proportion, the spatial position coefficient R is 0.3; when the content of useful minerals in the ore accounts for 30% to 60% of the total proportion, the spatial position coefficient R is 0.6; when the content of useful minerals in the ore accounts for ≥60% of the total proportion, the spatial position coefficient R is 1.

0.

4. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S1, the predicted ore recovery rate of banded ore bodies and ellipsoidal ore bodies is calculated by the following formula: Z=Q×G In the formula: Z is the predicted ore recovery rate; Q is the predicted single collapse volume; G is the ore body ratio, the G of the first layer of the strip ore body is 30%, and the G of the second layer of the strip ore body is 60%; the G of the first layer of the ellipsoidal ore body is 30%, and the G of the second layer of the ellipsoidal ore body is 60%, and the G of the ellipsoidal ore body greater than three layers is 100%.

5. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S2, the measured ore recovery rate of banded ore bodies and ellipsoidal ore bodies is calculated by the following formula: W=L×M Where: W is the measured ore recovery rate; L is the opening distance of the eyebrow line; M is the loose coefficient, M of the first layer of the strip-shaped ore body is 0.2, and M of the second layer is 0.5; M of the first layer of the ellipsoidal ore body is 0.3, M of the second layer is 0.6, and M of more than three layers is 0.

6.

6. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S2, the eyebrow opening distance is measured by an infrared rangefinder.

7. The method for determining the ore recovery rate of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S4, a hydraulic dynamic metering device is installed on the bucket of the scraper, which transmits the actual ore output to the central control system through the on-board computer and wireless network to determine the actual ore output.

8. The method for determining the ore yield of a pillarless sublevel caving mining method according to claim 1, characterized in that: In S4, the actual ore-extraction rate is calculated by the following formula: K=J / F×100% Where: K is the actual ore output rate; J is the actual single collapse volume; F is the actual ore output.

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