A high-efficiency tailings discarding and ore dressing method for off-balance sheet ore

Abstract

The present invention discloses an efficient tailing discarding method for off - surface ore, belonging to the technical field of mineral processing, and comprising the following steps: S1. Pretreatment: crushing the off - surface ore to obtain crushed raw ore; S2. Rough magnetic separation: performing rough magnetic separation operation on the crushed raw ore to obtain rough magnetic concentrate; S3. Fine magnetic separation: performing fine magnetic separation operation on the rough magnetic concentrate to obtain medium magnetic concentrate and tailing - discarded concentrate 1; S4. Secondary crushing: crushing the medium magnetic concentrate to obtain secondary - crushed ore; S5. Secondary magnetic separation: performing magnetic separation operation on the secondary - crushed ore to obtain tailing - discarded concentrate 2. Through the above technological process, finally, tailing - discarded concentrate with a yield of 71.52%, a TFe grade of 22.16%, a recovery rate of 90.02%, a TiO2 grade of 5.72%, and a recovery rate of 89.25% can be obtained. The present invention also discloses a beneficiation method for tailing - discarded concentrate. The method of the present invention can effectively solve the problem that off - surface ore cannot be effectively utilized due to low iron and titanium grades, and the process is simple and efficient.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral processing, and in particular relates to a high-efficiency tailings discarding method for off-balance sheet ores. Background Art

[0002] Vanadium-titanium magnetite is not only an important supplement to iron ore, but also the main carrier of vanadium-titanium resources. At the same time, some mines are associated with chromium, cobalt, scandium, gallium, etc., and are raw materials for various rare metals such as steel and vanadium-titanium. Conjugated steel and non-ferrous metals have extremely high strategic and comprehensive utilization value. my country is rich in vanadium-titanium magnetite resources, with proven reserves of more than 18 billion tons, mainly distributed in Panzhihua, Sichuan, Chengde, Hebei and other places. Among them, Panzhihua area is the largest vanadium-titanium magnetite production area in my country, with reserves of more than 10 billion tons. Although my country is rich in vanadium-titanium magnetite resources, the associated complex, low grade, high proportion of poor ore resources, and with the continuous utilization of vanadium-titanium magnetite resources and the increase in mining depth, the problems of "poor, fine and impure" vanadium-titanium magnetite will become more and more prominent. The off-balance sheet ores mined now are not used and are piled up in the spoil dump as waste rock. With the pressure of resource supply and the advancement of related technologies, off-balance sheet ores have become increasingly available iron ore resources, and these off-balance sheet ores have great potential for comprehensive utilization. The application of efficient development and utilization technology of this type of resources can effectively alleviate my country's dependence on imports of iron and titanium resources and reduce the pressure on the supply of strategic resources.

[0003] At present, the off-balance sheet mineral resources are mainly stored in the form of stockpiles, and only a small part of the relatively high-grade ore resources are utilized, and a large number of off-balance sheet mineral resources are in urgent need of utilization. However, the iron and titanium grades in the off-balance sheet ore are low. If they are not efficiently discarded, the operating costs of the mine (crushing cost, grinding cost and separation cost) will be greatly increased. Therefore, the efficient disposal of off-balance sheet ore, improving the grade of iron ore entering the mill, reducing the amount of ore entering the mill, and improving the processing capacity of the process are the most effective ways to utilize off-balance sheet ore. In the current low-grade ore mining process, more and more experts and scholars are guided by the academic idea of ​​"early collection, early disposal" in production practice. After years of production practice, it has been shown that ensuring that the minerals are sorted under coarse particle conditions as much as possible can effectively reduce the amount of grinding materials, reduce energy consumption, and achieve the purpose of increasing income and improving economic benefits. The large amount of waste tailings discharged during the production process have coarse particles, which are easy to stack and use in industries such as construction. They can also be used as filling materials in underground mining, which is conducive to the comprehensive utilization of tailings, environmental protection, and achieving the ultimate goal of energy conservation and emission reduction.

[0004] The document "Wang Yong. Experimental Study on Iron Resource Recovery of Panzhihua Baima Off-balance Ore [J]. Modern Mining, 2017, 33(05): 124-128." adopts dry tailings + wet tailings process to pre-discard off-balance ore with TFe grade of 16.73% and TiO2 grade of 3.73%, and obtains tailings concentrate with a yield of 42.34%, an iron grade of 28.11%, and an iron recovery rate of 71.14%. Subsequently, the tailings concentrate is subjected to a two-stage grinding process to obtain an iron concentrate with a yield of 38.29%, an iron grade of 55.52%, a TiO2 grade of 9.83%, and an iron recovery rate of 75.62%.

[0005] However, the TFe content in the tailings is high, resulting in large losses, and the iron concentrate obtained in the end has a low grade of iron. In addition, the process is complex and energy-intensive. For example, the process of dry tailings disposal + wet tailings disposal has the problem of being unable to be directly combined due to the different requirements of dry tailings disposal and wet tailings disposal on the initial state of the materials. Because dry tailings disposal requires the moisture content of the material to be less than 5%, while wet tailings disposal must rely on water as a medium, and there is a contradiction between the direct combination of the two; and dry magnetic separation equipment is used to select large, coarse-grained strong magnetic and fine-grained weak magnetic ores (beach sand), while wet magnetic separation equipment is used to select fine-grained strong magnetic ores and fine-grained weak magnetic ores, resulting in the need for certain pretreatment of the tailings after the dry tailings disposal before wet tailings disposal, which increases the workload.

[0006] Chinese invention patent CN101791588B discloses a method for selecting low-grade titanium-vanadium magnetite, which obtains high-grade vanadium-titanium iron concentrate by first crushing the raw ore, screening and magnetic separation, and then controlling the magnetic field intensity and belt speed during magnetic separation, and then grinding and magnetic separation twice.

[0007] After pre-discarding the tailings, a crude iron concentrate with a yield of 60.04%, a total iron grade of 23.65% and a total iron recovery rate of 73.88% can be obtained. After screening and demagnetization, it directly enters the main process and then undergoes a second grinding and magnetic separation to produce a vanadium-titanium iron concentrate with a TFe content of 55.70%.

[0008] However, the tailings concentrate also has low yield and recovery rate, and the TFe grade in the final vanadium-titanium-iron concentrate is also low. Summary of the invention

[0009] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for efficiently discarding tailings and beneficiating off-balance sheet ores, which can save energy and reduce consumption while also being able to discard qualified tailings in advance, thereby reducing the amount of tailings transported and improving the production capacity and production indicators of the process flow, and significantly increasing the economic benefits.

[0010] The objective of the present invention is achieved through the following technical solutions:

[0011] An efficient tailings discarding method for off-balance sheet ore comprises the following steps:

[0012] S1. Pretreatment: crushing the off-table ore to a particle size of -50 mm to obtain crushed raw ore;

[0013] S2. Magnetic roughing: The crushed ore is subjected to magnetic roughing to obtain magnetic rough concentrate and tailings;

[0014] Wherein, the magnetic field intensity of the rough magnetic separation operation is 477.6-557.2 kA / m;

[0015] S3. Magnetic separation and concentration: The magnetically separated coarse concentrate is subjected to magnetic separation and concentration to obtain magnetically separated ore and tailings concentrate 1;

[0016] Among them, the magnetic field intensity of the magnetic separation operation is 238.8-318.4kA / m.

[0017] Furthermore, the method further comprises the following steps:

[0018] S4. Secondary crushing: crushing the magnetic separation ore to a particle size of -12 mm to obtain secondary crushed ore;

[0019] S5. Secondary magnetic separation: The secondary crushed ore is subjected to magnetic separation to obtain tailings concentrate 2 and tailings;

[0020] Wherein, the magnetic field intensity of the magnetic separation operation is 318.4-398kA / m.

[0021] Furthermore, in the above-mentioned off-balance sheet ore, the TFe grade is 15-19%, and the TiO2 grade is 4-6%.

[0022] Furthermore, in step S1, the crushing is performed by a jaw crusher;

[0023] And / or, in step S4, the crushing is performed using a jaw crusher.

[0024] Furthermore, in step S1, the rough magnetic separation is performed using a dry magnetic separator;

[0025] And / or, in step S2, the magnetic separation is performed using a dry magnetic separator;

[0026] And / or, in step S5, the magnetic separation operation is performed using a dry magnetic separator.

[0027] Furthermore, in step S1, the rough magnetic separation equipment is selected from the Longi RCTS-5 dry belt magnetic separator;

[0028] In step S2, the magnetic separation equipment is Longi RCTS-5 dry belt magnetic separator;

[0029] In step S5, the equipment used for the magnetic separation operation is the LONGi RCTS-5 dry belt magnetic separator.

[0030] Furthermore, in step S1, the belt speed of the equipment during the rough magnetic separation is 1.1-1.3 m / s, and the feed rate is 2000 kg / h;

[0031] And / or, in step S2, the belt speed of the equipment during magnetic separation is 1.4-1.6 m / s, and the feed rate is 2000 kg / h;

[0032] And / or, in step S5, the belt speed of the equipment during the magnetic separation operation is 1.4-1.6 m / s, and the feed rate is 2000 kg / h.

[0033] The present invention also provides a method for beneficiating off-balance sheet ore tailings concentrate, comprising the following steps:

[0034] 1) crushing the tailings concentrate to -3 mm particle size using a jaw crusher to obtain selected raw ore;

[0035] 2) performing weak magnetic iron separation on the selected raw ore;

[0036] The weak magnetic iron separation operation includes three-stage grinding and three-stage weak magnetic iron separation, and the specific operation is: the selected raw ore is ground by a ball mill to a fineness of -0.075mm accounting for 50%, and the first weak magnetic iron separation is performed to obtain a rough iron concentrate 1 and a weak magnetic tailing 1; the rough iron concentrate 1 is further ground by a ball mill to a fineness of -0.075mm accounting for 80%, and the second weak magnetic iron separation is performed to obtain a rough iron concentrate 2 and a weak magnetic tailing 2; the rough iron concentrate 2 is ground by a ball mill again to a fineness of -0.038mm accounting for 90%, and the third weak magnetic iron separation is performed to obtain an iron concentrate and a weak magnetic tailing 3;

[0037] The weak magnetic iron separation operation includes a rough separation and a fine separation;

[0038] 3) combining the weak magnetic tailings 1, 2 and 3 to perform strong magnetic pre-enrichment titanium selection operation to obtain pre-enriched titanium concentrate and tailings 1;

[0039] The strong magnetic pre-enrichment titanium selection operation includes one roughing selection and two fine selections;

[0040] 4) performing a concentration flotation operation on the pre-enriched titanium concentrate to obtain titanium concentrate and tailings 2;

[0041] The pH value of the flotation operation is 3-4, the reagents used in the flotation operation include collectors and pH adjusters, and the flotation process includes one roughing, one scavenging, and five cleanings;

[0042] 5) Combine tailings 1 and tailings 2 into the total tailings.

[0043] Further, in step 2), the magnetic field strength of the roughing in the weak magnetic iron separation operation is 111.4kA / m, and the magnetic field strength of the fine separation is 95.5kA / m;

[0044] And / or, in step 3), the magnetic field strength of the roughing process in the strong magnetic pre-enrichment titanium selection operation is 636.8 kA / m, and the magnetic field strength of the fine selection process is 477.6 kA / m.

[0045] Furthermore, in step 4), the collector is MOH collector, the total amount is 2000-2500 g / t, and the pH adjuster is sulfuric acid.

[0046] The beneficial effects of the present invention are as follows: in view of the problems of low grade of valuable minerals in the current off-balance sheet ilmenite ore resources and large ore volume in the processing process, an efficient tailings discarding and ore dressing method for off-balance sheet ore is provided, which has the characteristics of simple process, obvious separation effect, energy saving and consumption reduction, and achieves the effect of effectively reducing the amount of grinding materials, increasing income and improving economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a high-efficiency tail-throwing flow chart of the present invention;

[0048] Figure 2 The present invention is a flow chart of the beneficiation of tailings concentrate. DETAILED DESCRIPTION

[0049] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0050] Example 1

[0051] This embodiment provides an efficient tailings discarding method for off-balance sheet ore. The experimental raw ore comes from an off-balance sheet ore of a titanium beneficiation plant in Panzhihua area. After multiple chemical analyses, it is known that its TFe grade is 17.61% and TiO2 grade is 4.58%, which is a low-grade ore that is difficult to utilize.

[0052] The mineral processing specifically includes the following steps:

[0053] (1) crushing the off-balance sheet ore to a particle size of -50 mm using a jaw crusher to obtain crushed raw ore:

[0054] (2) The crushed ore is subjected to a magnetic roughing operation, and a Longi RCTS-5 dry belt magnetic separator is selected, the magnetic field strength is controlled to be 517.4KA / m, the feeding belt speed is controlled to be 1.2m / s, and the feeding amount is 2000kg / h. After the roughing operation, a magnetically separated rough concentrate and tailings are obtained;

[0055] (3) The magnetically separated coarse concentrate is subjected to magnetic separation and concentration operation, using a Longi RCTS-5 dry belt magnetic separator, controlling the magnetic field strength to 278.6 KA / m, controlling the feed belt speed to 1.5 m / s, and the feed rate to 2000 kg / h, and obtaining magnetically separated ore and tailings concentrate after the concentration is completed;

[0056] (4) using a jaw crusher to perform secondary crushing on the magnetically separated ore to a particle size of -12 mm to obtain secondary crushed ore;

[0057] (5) The secondary crushed ore is subjected to magnetic separation operation, and a Longi RCTS-5 dry belt magnetic separator is selected, the magnetic field strength is controlled to 358.2KA / m, the feeding belt speed is controlled to 1.5m / s, and the feeding amount is 2000kg / h to obtain tailings concentrate and tailings.

[0058] Example 2

[0059] This embodiment provides an efficient tailings discarding method for off-balance sheet ore. The experimental raw ore comes from an off-balance sheet ore of a titanium beneficiation plant in Panxi area. After multiple chemical analyses, it is known that its TFe grade is 15.62% and TiO2 grade is 3.67%, which is a low-grade off-balance sheet ore that is difficult to utilize.

[0060] The mineral processing specifically includes the following steps:

[0061] (1) crushing the off-balance sheet ore to a particle size of -50 mm using a jaw crusher to obtain crushed raw ore:

[0062] (2) The crushed ore is subjected to a magnetic roughing operation, and a Longi RCTS-5 dry belt magnetic separator is selected, the magnetic field strength is controlled to be 517.4KA / m, the feeding belt speed is controlled to be 1.2m / s, and the feeding amount is 2000kg / h. After the roughing operation, a magnetically separated rough concentrate and tailings are obtained;

[0063] (3) The magnetically separated coarse concentrate is subjected to magnetic separation and concentration operation, using a Longi RCTS-5 dry belt magnetic separator, controlling the magnetic field strength to 278.6 KA / m, controlling the feed belt speed to 1.5 m / s, and the feed rate to 2000 kg / h, and obtaining magnetically separated coarse concentrate and tailings concentrate after the concentration is completed;

[0064] (4) using a jaw crusher to perform secondary crushing on the magnetically separated ore to a particle size of -12 mm to obtain secondary crushed ore;

[0065] (5) The secondary crushed ore is subjected to secondary magnetic separation, and a Longi RCTS-5 dry belt magnetic separator is selected to control the magnetic field strength to 358.2KA / m, the feeding belt speed to 1.5m / s, and the feeding amount to 2000kg / h to obtain tailings concentrate and tailings.

[0066] The results after treatment of the above-mentioned Example 1 and Example 2 are shown in Table 1:

[0067] Table 1 Results after treatment of Example 1 and Example 2

[0068]

[0069] As can be seen from Table 1, Example 1 can finally obtain a concentrate product with a yield of 71.52%, a TFe grade of 22.16%, a recovery rate of 90.02%, a TiO2 grade of 5.72%, and a recovery rate of 89.25%; Example 2 can finally obtain a concentrate product with a yield of 63.14%, a TFe grade of 21.15%, a recovery rate of 85.51%, a TiO2 grade of 4.85%, and a recovery rate of 83.53%.

[0070] Comparative Example 1

[0071] The only difference between Control Example 1 and Example 1 is that in step (1) of Control Example 1, the particle size of the crushed ore is changed to -70 mm, and other conditions such as equipment type, belt speed, magnetic field strength, medium ore crushing particle size and process flow are the same as those of Example 1 of the present invention.

[0072] Comparative Example 2

[0073] The only difference between Control Example 2 and Example 1 is that in step (1) of Control Example 2, the particle size of the crushed ore is changed to -25 mm, and other conditions such as equipment type, belt speed, magnetic field strength, medium ore crushing particle size and process flow are the same as those in Example 1 of the present invention.

[0074] The results after treatment of the above-mentioned Example 1 and Comparative Example 1 and Comparative Example 2 are shown in Table 2:

[0075] Table 2 Results after treatment of Example 1 and Comparative Example 1 and Comparative Example 2

[0076]

[0077]

[0078] As shown in Table 2, the final yield of Comparative Example 1 is 75.46%, the TFe grade is 20.27%, the recovery rate is 88.93%, the TiO2 grade is 4.98%, and the recovery rate is 86.11%. The final yield of Comparative Example 2 is 70.28%, the TFe grade is 21.02%, the recovery rate is 84.62%, the TiO2 grade is 5.30%, and the recovery rate is 84.89%.

[0079] Under the same other operating conditions, Control Example 1 only enlarged the roughing crushing particle size to -70mm, but the TFe grade of the concentrate product decreased by 1.89 percentage points, and the TFe recovery rate decreased by 1.09 percentage points; the TiO2 grade decreased by 0.74 percentage points, and the TiO2 recovery rate decreased by 3.14 percentage points; Control Example 2 only reduced the roughing crushing particle size to -25mm, but the TFe grade of the concentrate product decreased by 1.14 percentage points, and the TFe recovery rate decreased by 5.13 percentage points; the TiO2 grade decreased by 0.42 percentage points, and the TiO2 recovery rate decreased by 3.36 percentage points.

[0080] It can be seen that the control examples 1 and 2 respectively enlarged and reduced the crushing size of the raw ore, but had an adverse effect on the TFe grade, TiO2 grade, TFe recovery rate and TiO2 recovery rate of the concentrate product. When the crushing size of the raw ore is enlarged, the useful minerals and the gangue minerals are not fully dissociated, and due to the large particle size and uneven magnetic properties, the separation effect is poor, resulting in some gangue minerals entering the concentrate with the useful minerals, resulting in a lower concentrate grade. At the same time, some useful minerals enter the tailings with the gangue minerals, resulting in a lower recovery rate; when the crushing size of the raw ore is reduced, due to the increase in fine-grained useful minerals, the loss is large, resulting in a significant reduction in the concentrate recovery rate. Therefore, the crushed raw ore with a particle size of -50mm can better meet the roughing particle size requirements of magnetic separation.

[0081] Comparative Example 3

[0082] The only difference between Control Example 3 and Example 1 is that in step (2) of Control Example 3, the belt speed of the magnetic roughing operation is changed to 1.5 m / s, and other conditions such as the crushing particle size of the original ore, magnetic field strength, crushing particle size of the intermediate ore and process flow are the same as those of Example 1 of the present invention.

[0083] Comparative Example 4

[0084] The only difference between Control Example 4 and Example 1 is that in step (2) of Control Example 4, the belt speed of the magnetic roughing operation is changed to 0.72 m / s, and other conditions such as the crushing particle size of the original ore, magnetic field strength, crushing particle size of the intermediate ore and process flow are the same as those of Example 1 of the present invention.

[0085] The results after treatment of the above-mentioned Example 1 and Comparative Examples 3 and 4 are shown in Table 3:

[0086] Table 3 Results after treatment of Example 1 and Comparative Example 3 and Comparative Example 4

[0087]

[0088] As shown in Table 3, the final yield of Comparative Example 3 is 62.91%, the TFe grade is 22.42%, the recovery rate is 80.74%, the TiO2 grade is 5.79%, and the recovery rate is 81.22%. The final yield of Comparative Example 4 is 77.78%, the TFe grade is 19.77%, the recovery rate is 89.85%, the TiO2 grade is 5.06%, and the recovery rate is 90.63%.

[0089] Under the same other operating conditions, in control example 3, the belt speed was increased to 1.5 m / s only during the roughing of magnetic separation, but the TFe grade of the concentrate product was only increased by 0.26 percentage points, the TFe recovery rate decreased by 9.28 percentage points, the TiO2 grade increased by 0.07 percentage points, and the TiO2 recovery rate decreased by 8.03 percentage points. In control example 4, the belt speed was reduced to 0.75 m / s only during the roughing of magnetic separation, but the TFe grade of the concentrate product decreased by 2.39 percentage points, the TFe recovery rate increased by 0.17 percentage points, the TiO2 grade decreased by 0.66 percentage points, and the TiO2 recovery rate increased by 1.38 percentage points.

[0090] It can be seen that the belt speed of the magnetic roughing was increased and decreased in Control Example 1 and Control Example 2, respectively. However, increasing the belt speed had an adverse effect on the TFe recovery rate and TiO2 recovery rate of the concentrate product, while decreasing the belt speed had an adverse effect on the TFe grade and TiO2 grade of the concentrate product. Therefore, the belt speed of 1.2 m / s can better meet the requirements of the magnetic roughing belt speed.

[0091] Comparative Example 5

[0092] The only difference between Control Example 5 and Example 2 is that in step (2) of Control Example 5, the magnetic field strength of the rough magnetic separation operation is changed to 597KA / m, and other conditions such as the crushing particle size of the original ore, belt speed, crushing particle size of the intermediate ore and process flow are the same as those of Example 2 of the present invention.

[0093] Comparative Example 6

[0094] The only difference between Control Example 6 and Example 2 is that in step (2) of Control Example 6, the magnetic field strength of the rough magnetic separation operation is changed to 358.2KA / m, and other conditions such as the crushing particle size of the original ore, belt speed, crushing particle size of the intermediate ore and process flow are the same as those of Example 2 of the present invention.

[0095] The results after treatment of the above-mentioned Example 2 and Comparative Examples 5 and 6 are shown in Table 4:

[0096] Table 4 Results after treatment of Example 2 and Comparative Example 5 and Comparative Example 6

[0097]

[0098] As shown in Table 4, the final yield of Comparative Example 5 is 75.32%, the TFe grade is 18.41%, the recovery rate is 88.49%, the TiO2 grade is 4.35%, and the recovery rate is 88.76%. The final yield of Comparative Example 6 is 67.52%, the TFe grade is 19.86%, the recovery rate is 85.29%, the TiO2 grade is 4.68%, and the recovery rate is 84.24%.

[0099] Under the same other operating conditions, the control example 5 only enlarged the roughing magnetic field intensity to 597KA / m, but the TFe grade of the concentrate product decreased by 2.74 percentage points, the TFe recovery rate increased by 2.98 percentage points, the TiO2 grade decreased by 0.5 percentage points, and the TiO2 recovery rate increased by 5.23 percentage points. The control example 6 only reduced the roughing magnetic field intensity to 358.2KA / m, but the TFe grade of the concentrate product decreased by 1.29 percentage points, the TFe recovery rate decreased by 0.22 percentage points, the TiO2 grade decreased by 0.17 percentage points, and the TiO2 recovery rate increased by 0.71 percentage points.

[0100] It can be seen that the roughing magnetic field intensity was enlarged and reduced in Comparative Examples 5 and 6, respectively. Enlarging the roughing magnetic field intensity had a greater adverse effect on the TFe grade in the concentrate product, while reducing the roughing magnetic field intensity had an adverse effect on the TFe grade and recovery rate, as well as the TiO2 grade. Therefore, a magnetic field intensity of 517.4KA / m can better meet the roughing magnetic field intensity requirements.

[0101] Comparative Example 7

[0102] The only difference between Control Example 7 and Example 2 is that in step (4) of Control Example 7, the particle size of the secondary crushing of the magnetically separated ore is changed, and the magnetically separated ore is crushed to a particle size of -40 mm. Other conditions such as the particle size of the original ore crushing, magnetic field strength, belt speed and process flow are the same as those in Example 2 of the present invention.

[0103] Comparative Example 8

[0104] The only difference between Control Example 8 and Example 2 is that in step (4) of Control Example 8, the particle size of the secondary crushing of the medium ore is determined by magnetic separation, and the medium ore is crushed to a particle size of -25 mm. Other conditions such as the particle size of the original ore, magnetic field strength, belt speed and process flow are the same as those of Example 2 of the present invention.

[0105] The results of the above Example 2 and Comparative Examples 7 and 8 after treatment are shown in Table 5:

[0106] Table 5 Results after treatment of Example 2 and Comparative Examples 7 and 8

[0107]

[0108] As shown in Table 5, the final yield of comparative example 7 is 67.77%, the TFe grade is 17.87%, the recovery rate is 78.37%, the TiO2 grade is 4.15%, and the recovery rate is 79.55%. The final yield of example 8 is 71.79%, the TFe grade is 18.48%, the recovery rate is 85.18%, the TiO2 grade is 4.45%, and the recovery rate is 86.15%.

[0109] Under the same other operating conditions, the control example 7 only enlarged the particle size of the secondary crushing of the magnetic separation ore to -40mm, but the TFe grade of the concentrate product decreased by 3.28 percentage points, the TFe recovery rate decreased by 7.14 percentage points, the TiO2 grade decreased by 0.7 percentage points, and the TiO2 recovery rate decreased by 3.98 percentage points. The control example 8 only enlarged the particle size of the secondary crushing of the magnetic separation ore to -25mm, but the TFe grade of the concentrate product decreased by 2.67 percentage points, the TFe recovery rate decreased by 0.33 percentage points, the TiO2 grade decreased by 0.4 percentage points, and the TiO2 recovery rate increased by 2.62 percentage points.

[0110] It can be seen that the particle size of the secondary crushing of the medium ore was enlarged in Comparative Examples 7 and 8, but it had an adverse effect on the TFe grade, TiO2 grade and TFe recovery rate of the concentrate product. Similarly, when the crushing particle size was enlarged, the useful minerals and the gangue minerals were not fully dissociated, and due to the large particle size and uneven magnetic properties, the separation effect was poor, resulting in some gangue minerals entering the concentrate with the useful minerals, resulting in a lower concentrate grade. At the same time, some useful minerals entered the tailings with the gangue minerals, resulting in a lower recovery rate; therefore, the -12mm particle size crushing of the medium ore can better meet the particle size requirements.

[0111] Comparative Example 9

[0112] According to the method mentioned in the literature "Wang Yong. Experiment on the recovery of iron resources from the off-surface ore of Baima, Panzhihua [J]. Modern Mining, 2017, 33(05): 124-128.", the dry tailings discarding + wet tailings discarding process was used to pre-discard the raw ore with a TFe grade of 16.73% and a TiO2 grade of 3.73%, and a tailings concentrate with a yield of 42.34%, an iron grade of 28.11%, and an iron recovery rate of 71.14% was obtained.

[0113] Compared with Example 1, although the TFe enrichment effect of Comparative Example 9 is more obvious, the yield is only 42.34%, the recovery rate is only 71.14%, the TFe content in the discarded tailings is high, and the loss is large. It is more reasonable to have a pre-disposal tailing recovery rate of more than 80%. If it is lower than 80%, it does not meet the requirement of pre-disposal tailing work to discard low-grade gangue minerals without losing too much useful minerals. Therefore, considering comprehensively, the tailing method of the present invention has a better effect.

[0114] Example 3

[0115] This example conducts subsequent beneficiation operations on the concentrate product obtained after being treated by an efficient tailings discarding method of off-balance sheet ore in Example 1 to determine the impact of tailings discarding on subsequent beneficiation operations. The experimental ore comes from an off-balance sheet ore of a titanium beneficiation plant in Panxi area. After multiple chemical analyses, it is known that its TFe grade is 17.61% and TiO2 grade is 4.58%, which is a low-grade ore that is difficult to use. After the beneficiation steps of Example 1, a tailings discarded concentrate with a TFe grade of 22.16% and a TiO2 grade of 5.72% is obtained, and an iron and titanium selection test is carried out on it.

[0116] The mineral processing specifically includes the following steps:

[0117] 1) crushing the tailings concentrate to -3 mm particle size using a jaw crusher to obtain selected raw ore;

[0118] 2) performing weak magnetic iron separation on the selected raw ore;

[0119] The specific operation is as follows: the selected raw ore is ground by a ball mill to a fineness of -0.075mm accounting for 50%, and the first weak magnetic iron separation is performed to obtain a rough iron concentrate 1 and a weak magnetic tailing 1; the rough iron concentrate 1 is further ground by a ball mill to a fineness of -0.075mm accounting for 80%, and the second weak magnetic iron separation is performed to obtain a rough iron concentrate 2 and a weak magnetic tailing 2; the rough iron concentrate 2 is ground by a ball mill again to a fineness of -0.038mm accounting for 90%, and the third weak magnetic iron separation is performed to obtain an iron concentrate and a weak magnetic tailing 3;

[0120] The weak magnetic iron separation operation performs a roughing process and a fine separation process, wherein the magnetic field strength of the roughing process is 111.4 kA / m and the magnetic field strength of the fine separation process is 95.5 kA / m;

[0121] 3) combining the weak magnetic tailings 1, 2 and 3 to perform strong magnetic pre-enrichment titanium selection operation to obtain pre-enriched titanium concentrate and tailings 1;

[0122] The strong magnetic pre-enrichment titanium selection operation performs one roughing and two concentrating operations, wherein the magnetic field intensity of the roughing is 636.8KA / m and the magnetic field intensity of the concentrating is 477.6KA / m, to obtain pre-enriched titanium concentrate and tailings 1;

[0123] 4) The pre-enriched titanium concentrate is subjected to flotation operation, the pH value of the pulp is adjusted to 3-4 using sulfuric acid, MOH is used as a collector, the total amount of the MOH collector is 2200 g / t, and the flotation process is one roughing, one scavenging, and five concentrating to obtain titanium concentrate and tailings 2;

[0124] 5) Combine tailings 1 and tailings 2 into the total tailings.

[0125] Comparative Example 10

[0126] In this example, the raw ore in Example 1 is not treated by the high-efficiency tailings discarding method. The experimental raw ore comes from the off-balance sheet ore of a titanium beneficiation plant in Panxi area. According to multiple chemical analyses, its TFe grade is 17.61% and TiO2 grade is 4.58%. Iron and titanium beneficiation tests are carried out on it.

[0127] The mineral processing specifically includes the following steps:

[0128] 1) crushing the off-balance sheet ore to a particle size of -3 mm using a jaw crusher to obtain selected ore;

[0129] 2) performing weak magnetic iron separation on the selected raw ore;

[0130] The specific operation is as follows: the selected raw ore is ground by a ball mill to a fineness of -0.075mm accounting for 50%, and the first weak magnetic iron separation is performed to obtain a rough iron concentrate 1 and a weak magnetic tailing 1; the rough iron concentrate 1 is further ground by a ball mill to a fineness of -0.075mm accounting for 80%, and the second weak magnetic iron separation is performed to obtain a rough iron concentrate 2 and a weak magnetic tailing 2; the rough iron concentrate 2 is ground by a ball mill again to a fineness of -0.038mm accounting for 90%, and the third weak magnetic iron separation is performed to obtain an iron concentrate and a weak magnetic tailing 3;

[0131] The weak magnetic iron separation operation performs a roughing process and a fine separation process, wherein the magnetic field strength of the roughing process is 111.4 kA / m and the magnetic field strength of the fine separation process is 95.5 kA / m;

[0132] 3) combining the weak magnetic tailings 1, 2 and 3 to perform strong magnetic pre-enrichment titanium selection operation to obtain pre-enriched titanium concentrate and tailings 1;

[0133] The strong magnetic pre-enrichment titanium selection operation performs one roughing and two concentrating operations, wherein the magnetic field intensity of the roughing is 636.8KA / m and the magnetic field intensity of the concentrating is 477.6KA / m, to obtain pre-enriched titanium concentrate and tailings 1;

[0134] 4) The pre-enriched titanium concentrate is subjected to flotation operation, the pH value of the pulp is adjusted to 3-4 using sulfuric acid, MOH is used as a collector, the total amount of the MOH collector is 2200 g / t, and the flotation process is one roughing, one scavenging, and five concentrating to obtain titanium concentrate and tailings 2;

[0135] 5) Combine tailings 1 and tailings 2 into the total tailings.

[0136] The results of the above comparative example 10 are shown in Table 6:

[0137] Table 6 Results of Example 3 and Comparative Example 10

[0138]

[0139]

[0140] Compared with Example 3, the difference between Comparative Example 10 and Example 3 is whether the raw ore product treated by the efficient tailings discarding method of this scheme is used for subsequent iron and titanium selection tests. The results show that although the recovery rates of iron and titanium of the final product not treated by the efficient tailings discarding method of this scheme are not much lower than those of the treated products, the TFe grade and TiO2 grade of the untreated iron concentrate and titanium concentrate are 5 percentage points and 2 percentage points lower than those of the treated products of iron, ilmenite concentrate and titanium concentrate, respectively, and fail to meet the requirements of qualified concentrates currently required for products. Therefore, the efficient tailings discarding method can effectively improve the grade of subsequent iron and titanium concentrate products to meet product requirements, and at the same time, the impact on their recovery rate is not great. The comparison shows that the ore after tailings discarding of the present invention has a better effect in the vanadium-titanium magnetite beneficiation, and is suitable for the beneficiation production of off-balance sheet ores.

[0141] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. An efficient tailings disposal method for off-balance sheet ores, characterized in that: The following steps are involved: S1. Pretreatment: crushing the off-table ore to a particle size of -50 mm to obtain crushed raw ore; S2. Magnetic roughing: The crushed ore is subjected to magnetic roughing to obtain magnetic rough concentrate and tailings; Wherein, the magnetic field intensity of the rough magnetic separation operation is 477.6-557.2 kA / m; S3. Magnetic separation and concentration: The magnetically separated coarse concentrate is subjected to magnetic separation and concentration to obtain magnetically separated ore and tailings concentrate 1; Wherein, the magnetic field intensity of the magnetic separation operation is 238.8-318.4 kA / m; S4. Secondary crushing: crushing the magnetic separation ore to a particle size of -12 mm to obtain secondary crushed ore; S5. Secondary magnetic separation: The secondary crushed ore is subjected to magnetic separation to obtain tailings concentrate 2 and tailings; Wherein, the magnetic field intensity of the magnetic separation operation is 318.4-398kA / m; In the above-mentioned off-balance sheet ore, the TFe grade is 15-19%, and the TiO2 grade is 4-6%.

2. A highly efficient tailings discarding method for off-balance sheet ore according to claim 1, characterized in that: In step S1, the crushing is performed by a jaw crusher; And / or, in step S4, the crushing is performed using a jaw crusher.

3. A highly efficient tailings discarding method for off-balance sheet ore according to claim 1, characterized in that: In step S1, the rough magnetic separation is performed using a dry magnetic separator; And / or, in step S2, the magnetic separation is performed using a dry magnetic separator; And / or, in step S5, the magnetic separation operation is performed using a dry magnetic separator.

4. A highly efficient tailings discarding method for off-balance sheet ore according to claim 1, characterized in that: In step S1, the rough magnetic separation equipment is Longi RCTS-5 dry belt magnetic separator; In step S2, the magnetic separation equipment is Longi RCTS-5 dry belt magnetic separator; In step S5, the equipment used for the magnetic separation operation is the LONGi RCTS-5 dry belt magnetic separator.

5. A highly efficient tailings disposal method for off-balance sheet ore according to claim 4, characterized in that: In step S1, the belt speed of the equipment during the rough magnetic separation is 1.1-1.3 m / s, and the feed rate is 2000 kg / h; And / or, in step S2, the belt speed of the equipment during magnetic separation is 1.4-1.6 m / s, and the feed rate is 2000 kg / h; And / or, in step S5, the belt speed of the equipment during the magnetic separation operation is 1.4-1.6 m / s, and the feed rate is 2000 kg / h.

6. A highly efficient tailings discarding method for off-balance sheet ore according to any one of claims 1 to 5, characterized in that: It also includes the beneficiation method of the tailings concentrate of off-balance sheet mines: The ore dressing method of the tailings concentrate comprises the following steps: 1) crushing the tailings concentrate to -3 mm particle size using a jaw crusher to obtain selected raw ore; 2) performing weak magnetic iron separation on the selected raw ore; The weak magnetic iron separation operation includes three-stage grinding and three-stage weak magnetic iron separation, and the specific operation is: the selected raw ore is ground by a ball mill to a fineness of -0.075mm accounting for 50%, and the first weak magnetic iron separation is performed to obtain a rough iron concentrate 1 and a weak magnetic tailing 1; the rough iron concentrate 1 is further ground by a ball mill to a fineness of -0.075mm accounting for 80%, and the second weak magnetic iron separation is performed to obtain a rough iron concentrate 2 and a weak magnetic tailing 2; the rough iron concentrate 2 is ground by a ball mill again to a fineness of -0.038mm accounting for 90%, and the third weak magnetic iron separation is performed to obtain an iron concentrate and a weak magnetic tailing 3; The weak magnetic iron separation operation includes a rough separation and a fine separation; 3) combining the weak magnetic tailings 1, 2 and 3 to perform strong magnetic pre-enrichment titanium selection operation to obtain pre-enriched titanium concentrate and tailings 1; Wherein, the strong magnetic pre-enrichment titanium selection operation includes one roughing selection and two fine selections; 4) performing a concentration flotation operation on the pre-enriched titanium concentrate to obtain titanium concentrate and tailings 2; The pH value of the flotation operation is 3-4, the reagents used in the flotation operation include collectors and pH adjusters, and the flotation process includes one roughing, one scavenging, and five cleanings; 5) Combine tailings 1 and tailings 2 into the total tailings.

7. The high-efficiency tailings discarding method of off-balance sheet ore according to claim 6, characterized in that: In step 2), the magnetic field strength of the roughing in the weak magnetic iron separation operation is 111.4kA / m, and the magnetic field strength of the fine selection is 95.5kA / m; And / or, in step 3), the magnetic field strength of the roughing process in the strong magnetic pre-enrichment titanium selection operation is 636.8 kA / m, and the magnetic field strength of the fine selection process is 477.6 kA / m.

8. The high-efficiency tailings discarding method of off-balance sheet ore according to claim 6, characterized in that: In step 4), the collector is MOH collector, the total amount is 2000-2500 g / t, and the pH adjuster is sulfuric acid.

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