Ore blending method for stabilizing grade of raw ore

Abstract

The invention discloses an ore blending method for stabilizing the grade of raw ore, and belongs to the technical field of mining. Comprising the following steps: formulating an ore blending stope continuing network diagram, dynamically allocating the ore removal amount of the ore blending stope, and timely scheduling surface ore blending. According to the method, ore blending is carried out in a planned, targeted and dynamic regulation and control mode, and grade stability is ensured; and in combination with ore body analysis and matching control, subsequent processes such as ore grinding and flotation are facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of mining, and particularly relates to a ore blending method for stabilizing the grade of raw ore. Background Art

[0002] The mineralization degree of each ore body in the mining area is uneven, and the proportion of low-grade ore is relatively large; in order to complete the annual production index, reasonable design is required. For example, at the end of the year, the average grade of the developed ore volume in a certain mine of our company is 3.77 g / t, the average grade of the preparatory ore volume is 4.10 g / t, and the average grade of the ore volume reserved for mining is 4.21 g / t. If the next year's production is to be completed, it is planned to process raw ore with a grade of 5.76 g / t, which is much higher than the average grade of the three-level ore volume. If production is organized step by step, the planned requirements cannot be met. Summary of the Invention

[0003] The purpose of the present invention is to propose an ore blending method for stabilizing the grade of raw ore, and to improve the quality of raw ore by adopting scientific and reasonable ore blending means.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions: An ore blending method for stabilizing the grade of raw ore, comprising: formulating a connection network diagram for ore blending stope, dynamically adjusting the ore output of the ore blending stope, and timely scheduling the surface ore blending.

[0005] Preferably, in formulating the connection network diagram for ore blending stope: Statistically analyze the grades of ore blocks to be exploited in the annual plan, list the high-grade ore rooms with ore blending value and the low-grade ore rooms on both wings; Investigate and analyze the production status of high-grade ore rooms, and formulate a connection network diagram for ore blending stope on a quarterly basis and strictly implement it based on the principle that there must be 1-2 ore blending stopes with ore extraction conditions every month, so as to avoid the situation of no ore available for blending in any month; At the same time, when formulating the monthly production plan, try to make the low-grade stopes and high-grade ore rooms extract ore simultaneously to achieve the purpose of mining both rich and poor ores.

[0006] Preferably, in the dynamic adjustment of the ore output of the ore blending stope: timely adjust the ore output of the ore blending stope through scientific calculation to keep the selected grade stable within a reasonable range.

[0007] Preferably, in the dynamic adjustment of the ore output of the ore blending stope, the calculation formula is as follows: ; Wherein: AG is: the target raw ore grade (g / t); G1, G2…G n is: the grade of the ore blending stope on the same day (g / t); W1, W2…W n is: the amount of ore output per shift (t) that needs to be increased or decreased in the corresponding ore blending stope to achieve the target raw ore grade; RE is: the average recovery rate in the recent three shifts (%); O AU is: the average daily gold output per shift in the recent three shifts (g); W 总 is: the average ore processing volume per shift in the recent three shifts (t).

[0008] Preferably, in the timely scheduling of surface ore blending: The stored ore in the surface ore yard is divided into several areas, and the sampling personnel take samples of the surface ore yard every day; at the same time, samples are taken from the ore just delivered to the surface ore yard; According to the actual selected grade of the previous shift, contact the batching forklift driver in time, specify the feeding area, and purposefully feed the ore with appropriate grade into the bunker to achieve the auxiliary adjustment of the selected grade.

[0009] Preferably, it also includes: the discovery and solution of influencing factors during abnormal periods of raw ore grade; When the grade is abnormal during a certain period, systematically analyze the grade, ore output, and transportation path of each underground ore output working face, and calculate the grade of each ore discharge chute; then, adjust the number of ore trucks in the low-grade or high-grade ore discharge chutes according to the stored ore grade of each chute.

[0010] Preferably, in the discovery and solution of influencing factors during abnormal periods of raw ore grade, formulate a theoretical selected grade calculation table; List the ore output tons, grades, and raw ore metal amounts of each ore output working face in each middle section; And list the lifting volume, average chute grade, and raw ore metal amount of each ore discharge chute, as well as the tons, average grade, and raw ore metal amount of the surface ore yard.

[0011] Preferably, it also includes: monitoring the grade conditions of each ore room and each ore chute shaft; ① If the grade of a single stope is continuously low, investigate: whether there is a serious over-mining phenomenon in the surrounding rock of the stope, whether the primary and secondary dilution rates exceed the design index, whether there are removable intercalated rocks, and whether the ore body has changed; if there are problems, strictly control the upper and lower boundaries of the ore body, remove the intercalated rocks that need to be removed, re-circumscribe the ore body with obvious changes in morphology, and change the mining design according to the changes in the ore body; ② If the grade of an individual ore chute is low and all the stopes in the ore chute are low-grade ore rooms, re-analyze whether the mining sequence of each ore room in the corresponding middle section is reasonable and whether it has the conditions for adjustment, and try to achieve a combination of rich and poor ores and a balance between difficult and easy mining.

[0012] Preferably, the method further comprises: discovering influencing factors by comparing theoretical and actual raw ore grades; When the theoretical selected grade is not much different from the actual selected grade, the output of high-grade ore is adjusted; if the blending mine has exerted its maximum supply capacity and still cannot achieve the blending effect, a new blending mine is opened to supplement it.

[0013] Preferably, among the influencing factors found by comparing theoretical and actual ore grades: If the theoretical selected grade is much higher than the actual selected grade, you need to check whether the following situations exist: ① Whether the ore grade of the ore-matching mining area is uniform, and whether the actual grade of the ore-matching mining area is overestimated; Solution: Take samples from the ore-matching stope system and calculate a more representative average grade, so as to adjust the ore output of the ore-matching stope; ② Take samples of the ores that have recently been brought to the surface yard to determine whether the high-grade ores have been brought to the surface yard and have not entered the mineral processing process; Solution: If the ore grade just hit the surface is high and the high-grade ore has not entered the process, it is necessary to investigate the reasons why the high-grade ore has not entered the beneficiation process. The common reason is that the ore in the blending stope or the middle section has a large amount of moisture, and the wet material is hit to the surface to dry and cannot enter the beneficiation process in time. In this case, it is necessary to focus on solving the drainage problem in the stope to avoid water accumulation in the mine room causing wet materials. ③Investigate whether there is any mixing of ore and wool; Solution: Take measures such as dispatching monitoring and on-site supervision to strictly control the mixing of ore and rough rock, focus on the whereabouts of waste rock from the construction of the connecting tunnels in the middle section of the mining area and the waste rock from each wing, and establish a ledger of the whereabouts of rough rock.

[0014] Compared with the prior art, the present invention provides a method for blending ore to stabilize the grade of raw ore, which has the following beneficial effects.

[0015] 1. The present invention formulates a connection network diagram of the ore distribution field, dynamically adjusts the ore output of the ore distribution field, and timely dispatches the surface ore distribution to ensure stable grade in a planned, targeted and dynamic manner; and combines ore body analysis with matching control to facilitate subsequent grinding, flotation and other processes.

[0016] Other advantages, objectives and features of the present invention will be described in part in the following description; and in part, will be apparent to those skilled in the art based on an examination of the following; or, may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Connecting the mining site to the network Figure 1 .

[0018] Figure 2 For the stope connection network Figure 2 。

[0019] Figure 3 It is a theoretical selected grade calculation table. Specific implementation manners

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0021] Refer to Figures 1-3 , a ore blending method for stabilizing the grade of raw ore, including: formulating a ore blending stope connection network diagram, dynamically adjusting the ore output of the ore blending stope, and timely scheduling the surface ore blending.

[0022] In formulating the ore blending stope connection network diagram: Statistically analyze the grades of the ore blocks to be exploited in the annual plan (the plan at the end of the year for the next year), list the high-grade ore rooms with ore blending value, and the low-grade ore rooms on both wings.

[0023] Investigate and analyze the production status of the high-grade ore rooms. In principle, there must be 1-2 ore blending stopes with ore extraction conditions every month. Formulate the ore blending stope connection network diagram on a quarterly basis and strictly implement it to avoid the situation of no ore available for blending in any month.

[0024] At the same time, when formulating the monthly production plan, try to make the low-grade stopes and high-grade ore rooms extract ore at the same time to achieve the purpose of mining both rich and poor ores.

[0025] Such as Figure 1 、 2 shown; adjust the operation according to the situation of each stope, control from the basic ore extraction; and match with other dynamic adjustments to achieve overall comprehensive ore blending.

[0026] In the dynamic adjustment of the ore output of the ore blending stope: Due to the uneven mineralization degree of the ore body, the fluctuation of the raw ore grade is relatively large. Especially, the grade fluctuation of the ore blending stope will directly affect the ore blending effect; this requires us to strengthen the daily dynamic supervision in the ore blending work; during the operation of the ore blending stope, samples should be taken every day, and according to the test results of the samples on the same day, the ore output of the ore blending stope should be adjusted in time through scientific calculation to keep the selected grade stable within a reasonable range.

[0027] In the dynamic adjustment of the ore output of the ore blending stope, the calculation formula is as follows 。

[0028] Wherein: AG is: the target original ore grade (g / t); G1, G2…G n is: the grade of the ore mined in the ore blending stope on the current day (g / t); W1, W2…W n is: the amount of ore to be increased or decreased per shift (t) in the corresponding ore blending stope to reach the target original ore grade; RE is: the average recovery rate in the last three shifts (%); O AU is: the average daily gold production per shift in the last three shifts (g); W 总 is: the average amount of ore processed per shift in the last three shifts (t).

[0029] It should be noted that: in the calculation, multiple blending schemes will be formed; the amount of ore mined per shift is limited; the constraint conditions (the amount of ore mined) are adjusted within the controllable range of increase and decrease to generate an optimal scheme. In this process, computer assistance can be used for calculation.

[0030] In the timely scheduling of surface ore blending: A part of the ore hoisted underground on the current day enters the surface stockyard and does not enter the beneficiation process. A part of the ore processed by the concentrator on the current day also comes from the surface bunker; Supervising and scheduling the feeding link of the surface stockyard is another direct means of ore blending.

[0031] In order to timely understand the distribution of high-grade and low-grade ores in the surface stockyard, the ore stored in the surface stockyard is divided into several areas, and the surface stockyard is sampled by the sample cutting personnel every day; at the same time, the ore just delivered to the surface stockyard is sampled.

[0032] According to the actual grade of the ore selected in the previous shift, contact the driver of the batching forklift in time, specify the feeding area, and purposefully feed the ore with an appropriate grade into the bunker to achieve the auxiliary adjustment of the grade of the ore selected.

[0033] In some embodiments, it further includes: the discovery and solution of the influencing factors during the abnormal period of the original ore grade.

[0034] In actual production, it often happens that ore blending measures are taken but the ore blending effect is not achieved; this requires us to timely discover the problem and quickly determine the solution according to the influencing factors.

[0035] Therefore, when the grade is abnormal in a certain period, systematically analyze the grade, the amount of ore mined, and the transportation path of each underground ore mining face, and calculate the grade of each ore discharge chute; then, adjust the number of ore trucks in the low-grade or high-grade ore discharge chutes according to the ore grade stored in each chute.

[0036] Furthermore, in the discovery and solution of influencing factors during abnormal periods of the raw ore grade: To facilitate calculations, a theoretical feed grade calculation table is formulated.

[0037] As Figure 3 shown; List the ore output tons, grades, and raw ore metal amounts of the ore extraction working faces at each level; List the hoisting amounts, average grades of the ore passes, and raw ore metal amounts of each ore pass, as well as the tons, average grades, and raw ore metal amounts of the surface ore yard; Calculate the theoretical feed grade.

[0038] The feed grade calculation table can not only be used as a basis for adjusting the number of ore cars discharged from each ore pass; when the raw ore grade is abnormal, it can also assist in analyzing the influencing factors to promptly discover and solve problems.

[0039] In some embodiments, it further includes: monitoring the grade conditions of each ore room and each ore pass shaft.

[0040] ① If the grade of a single stope is continuously low, it is necessary to investigate: Whether there is a serious over-mining phenomenon in the surrounding rock of this stope; Whether the primary and secondary dilution rates exceed the design indicators; Whether there are removable intercalated rocks; Whether the ore body has changed.

[0041] If there are problems, strictly control the upper and lower boundaries of the ore body, remove the intercalated rocks that need to be removed, re-circle the ore body with obvious changes in shape, and change the mining design according to the changes in the ore body.

[0042] ② If the grade of an individual ore pass is low and all the stopes in the ore pass are low-grade ore rooms, re-analyze whether the stoping sequence of each ore room in the level is reasonable and whether there are conditions for adjustment; try to achieve a combination of rich and poor ores and a balance between easy and difficult mining.

[0043] In some embodiments, it further includes: discovering influencing factors by comparing the theoretical and actual raw ore grades.

[0044] Based on past experience, when there are no obvious influencing factors, the difference between the theoretical feed grade and the actual feed grade within ±1.6 g / t is regarded as a normal error.

[0045] When the difference between the theoretical feed grade and the actual feed grade is not significant, adjust by adjusting the ore output of high-grade ores. At this time, if the ore blending stope has exerted its maximum ore supply capacity and still cannot achieve the ore blending effect, a new ore blending stope is opened for supplementation.

[0046] If the theoretical feed grade is much greater than the actual feed grade, it is necessary to check whether the following situations exist.

[0047] ① Whether the ore grade of the ore blending stope is uniform and whether the actual grade of the ore blending stope is overestimated; Solution: Take systematic samples from the ore blending stope, calculate a more representative average grade, and adjust the ore output of the ore blending stope accordingly.

[0048] ② Take samples of the ore that has just been mined to the surface stockpile recently to determine whether high-grade ore has been mined to the surface stockpile but not entered the beneficiation process; Solution: If the grade of the ore just mined to the surface is high and the high-grade ore has indeed not entered the process, it is necessary to investigate the reason why the high-grade ore fails to enter the beneficiation process; the common reason is that the moisture content of the ore in the ore blending stope or the relevant level is relatively high, and the ore is mined to the surface to dry due to wet material and cannot enter the beneficiation process in time; in this case, it is necessary to focus on solving the drainage problem in the stope to avoid water accumulation in the ore chamber causing wet material.

[0049] ③ Investigate whether there is a situation of mixing ore fines and waste rock; Solution: Take measures such as dispatching monitoring and on-site follow-up to strictly control the mixing of ore fines and waste rock, focus on the whereabouts of the waste rock from the crosshead construction of each level stope and the waste rock from each wing, and establish a ledger for the whereabouts of the waste rock.

[0050] In some embodiments, it further includes: making a combination according to the principle of reducing impurities.

[0051] Conduct a detailed analysis of the impurity elements in the ore of each stope, determine their contents and the degree of influence on the beneficiation process; pay special attention to the impurity elements that have a greater impact on the beneficiation process, such as sulfur, arsenic, etc. During the ore blending process, combine ores with different impurity contents to reduce the impurity content in the mixed raw ore; for ores with a higher impurity content, the proportion of them in the ore blending can be appropriately reduced, and pretreatment measures (such as washing) can be taken to reduce the impurity content before making a combination.

[0052] In some embodiments, it further includes: making a combination according to the ore body composition.

[0053] Sample and analyze the ore body, and determine which minerals are beneficial to the beneficiation process and which minerals may have an adverse impact according to the analysis results in combination with the differences and influences of different mineral compositions. For example, ores containing appropriate amounts of sulfide minerals such as pyrite and chalcopyrite may be beneficial to the flotation of gold; while ores containing excessive amounts of minerals such as talc and chlorite may reduce the flotation effect; when blending ore into the bunker, make a reasonable combination.

[0054] Formulate a reasonable combination strategy according to the analysis results of the ore body composition.

[0055] Try to select ores with complementary mineral compositions for blending to optimize the mineral composition of the mixed ore and improve the beneficiation efficiency. For example, ores rich in sulfide minerals can be blended with ores containing appropriate amounts of gangue minerals such as quartz; by utilizing the hardness difference, mutual interactions can occur between ore particles during the grinding process, and the harder quartz particles help break the softer sulfide mineral particles, making the grinding process more efficient and reducing the grinding time and energy consumption. At the same time, appropriate ore blending can make the particle size distribution of the grinding product more reasonable, which is beneficial to improving the recovery rate of subsequent beneficiation methods such as flotation.

[0056] Optimize the flotation index according to the analysis results of the ore body composition.

[0057] The properties of sulfide minerals and quartz in the pulp are different; quartz is a gangue mineral and usually needs to be inhibited during the flotation process; when blending ores, control the ratio of sulfide minerals and quartz and adjust the properties of the pulp such as acidity, alkalinity, and potential. For example, in a sulfide ore flotation system, an appropriate amount of quartz can stabilize the pH value of the pulp, which is beneficial for reagents such as collectors to exert their best performance. At the same time, when the ratio of sulfide minerals and quartz is appropriate, the collector can be more targeted to adsorb on the surface of sulfide minerals, while the inhibitor can more effectively inhibit the flotation of quartz, thereby improving the grade and recovery rate of sulfide ore concentrates.

[0058] In some embodiments, it further includes: continuous optimization and improvement.

[0059] Regularly evaluate the implementation effect of the ore blending plan; use data analysis methods (such as statistical analysis, regression analysis, etc.) to analyze the improvement degree of each ore blending parameter and the output. Summarize experience and lessons based on the evaluation results and adjust and optimize the ore blending plan; for example, if it is found that the effect of a certain blending method is not good, preferably adopt other blending methods.

[0060] Closely follow new technologies and new methods in the industry, and actively introduce and apply advanced ore blending technologies and equipment; for example, intelligent ore blending systems, on-line analysis and detection technologies, etc., to improve the accuracy and efficiency of ore blending.

[0061] Carry out scientific research and tackle key problems to explore more scientific and efficient ore blending methods; cooperate with scientific research institutions, universities, etc. to jointly carry out research on ore blending technologies and solve problems in actual production. For example, research the use of big data and artificial intelligence technologies for ore blending optimization to improve the efficiency and accuracy of ore blending.

[0062] In the present invention, by taking reasonable ore blending measures, while the average grade of the reserved resource volume shows a decreasing trend year by year, every effort is made to improve the quality of the raw ore and strive to ensure the stability of the raw ore grade. In the middle of the year, the task of achieving more than half of the gold output was completed 27 days ahead of schedule; at the end of the year, the cumulative treated raw ore grade was 6.61 g / t, and the gold output completed 127.52% of the annual plan, providing strong support for the company to set a new high in the annual gold output target.

[0063] In the present invention, by formulating a network diagram for the continuous mining of ore blending stope, dynamically adjusting the ore output of the ore blending stope, and timely scheduling the surface ore blending, etc., ore blending is carried out in a planned, targeted and dynamic manner to ensure grade stability; and combined with ore body analysis and matching control, it is beneficial to subsequent processes such as grinding and flotation.

[0064] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered within the protection scope of the present invention.

[0065] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0066] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for stabilizing the grade of raw ore, characterized in that: include: Develop a network diagram for the connection between the ore distribution sites, dynamically adjust the output of the ore distribution sites, and timely dispatch the surface ore distribution.

2. The ore blending method for stabilizing the grade of raw ore according to claim 1, characterized in that: In the formulation of the ore distribution and stope connection network diagram: Conduct statistical analysis on the grade of the ore blocks planned to be used annually, and list the high-grade ore rooms with ore allocation value, as well as the low-grade ore rooms on both wings; Investigate and analyze the production status of high-grade ore rooms. Based on the principle that there must be 1-2 ore-matching sites that meet the conditions for mining every month, formulate a network diagram for ore-matching sites on a quarterly basis and strictly implement it to avoid the situation where there is no ore to match in any month. At the same time, when formulating the monthly production plan, we try to make the low-grade mining area and the high-grade ore room produce ore at the same time to achieve the goal of mining both poor and rich products.

3. The ore blending method for stabilizing the grade of raw ore according to claim 1, characterized in that: In the dynamic allocation of ore output from the ore distribution mining area: timely adjust the ore output from the ore distribution mining area through scientific calculations to stabilize the selected grade within a reasonable range.

4. The ore blending method for stabilizing the grade of raw ore according to claim 3, characterized in that: In the dynamic allocation of ore output in the ore distribution field, the calculation formula is as follows: in: AG is: target ore grade (g / t); G1, G2…G n is: grade of the ore-matching stope on the day (g / t); W1, W2…W n =To achieve the target ore grade, the corresponding ore distribution mining field needs to increase or decrease the ore output per shift (t); RE is: the average recovery rate of the last three classes (%); O AU The average gold production of each shift in the last three shifts (g); W 总 is: the average ore processing volume of each shift in the past three shifts (t).

5. The ore blending method for stabilizing the grade of raw ore according to claim 1, characterized in that: In the timely dispatch of surface ore: The surface material field is divided into several areas, and the sampling personnel take samples from the surface material field every day; at the same time, the ore that has just been brought to the surface material field is sampled; According to the actual selected grade of the previous shift, contact the batching shovel driver in time, designate the feeding area, and purposefully feed the silo with ore of appropriate grade to achieve auxiliary adjustment of the selected grade.

6. The ore blending method for stabilizing the grade of raw ore according to any one of claims 1 to 5, characterized in that: Also includes: Discovery and resolution of factors affecting the period of abnormal ore grade; When the grade in a certain period of time is abnormal, a systematic analysis is conducted on the grade, ore output and transportation routes of each mining face underground to calculate the grade of each ore chute; then, the number of ore cars for low-grade or high-grade chutes is adjusted according to the grade of the ore in each chute.

7. The ore blending method for stabilizing the grade of raw ore according to claim 6, characterized in that: In the discovery and solution of the factors affecting the abnormal period of raw ore grade, a theoretical selected grade calculation table is formulated; List the ore output tonnage, grade, and raw ore metal content of each middle section of the mining operation face; It also lists the lifting capacity of each ore chute, the average grade of the chute, the amount of metal in the original ore, as well as the tonnage, average grade, and amount of metal in the original ore of the surface mine.

8. The ore blending method for stabilizing the grade of raw ore according to claim 7, characterized in that: Also includes: Monitor the grade of each mine room and each chute; ① If the grade of a single stope is continuously low, investigate whether the surrounding rock of the stope is seriously over-mined, whether the primary and secondary depletion rates exceed the design indicators, whether there are interlayers that can be removed, and whether the ore body has changed; if there are problems, strictly control the upper and lower boundaries of the ore body, remove the interlayers that need to be removed, conduct secondary delineation for ore bodies with obvious changes in shape, and change the mining design according to the changes in the ore body; ② If the grade of individual chutes is low and the mining areas within the chutes are all low-grade ore rooms, re-analyze whether the mining order of each ore room in the middle section is reasonable and whether the conditions for adjustment are met, so as to achieve both rich and poor mining and both difficult and easy mining as much as possible.

9. The ore blending method for stabilizing the grade of raw ore according to claim 8, characterized in that: Also includes: Discover the influencing factors by comparing theoretical and actual ore grades; When the theoretical selected grade is not much different from the actual selected grade, the output of high-grade ore is adjusted; if the blending mine has exerted its maximum supply capacity and still cannot achieve the blending effect, a new blending mine is opened to supplement it.

10. The ore blending method for stabilizing the grade of raw ore according to claim 9, characterized in that: Among the influencing factors found by comparing theoretical and actual ore grades: If the theoretical selected grade is much higher than the actual selected grade, you need to check whether the following situations exist: ① Whether the ore grade of the ore-matching mining area is uniform, and whether the actual grade of the ore-matching mining area is overestimated; Solution: Take samples from the ore-matching stope system and calculate a more representative average grade, so as to adjust the ore output of the ore-matching stope; ② Take samples of the ores that have recently been brought to the surface yard to determine whether the high-grade ores have been brought to the surface yard and have not entered the mineral processing process; Solution: If the ore grade just hit the surface is high and the high-grade ore has not entered the process, it is necessary to investigate the reasons why the high-grade ore has not entered the beneficiation process. The common reason is that the ore in the blending stope or the middle section has a large amount of moisture, and the wet material is hit to the surface to dry and cannot enter the beneficiation process in time. In this case, it is necessary to focus on solving the drainage problem in the stope to avoid water accumulation in the mine room causing wet materials. ③Investigate whether there is any mixing of ore and wool; Solution: Take measures such as dispatching monitoring and on-site supervision to strictly control the mixing of ore and rough rock, focus on the whereabouts of waste rock from the construction of the connecting tunnels in the middle section of the mining area and the waste rock from each wing, and establish a ledger of the whereabouts of rough rock.

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