Method of dressing iron-bearing ores

FIELD: process engineering.

SUBSTANCE: invention relates to ore dressing and may be used in mining and metallurgy. Proposed method comprises three stages of crushing, wet magnetic separation of crushed products of every said stage to obtain middling, final tailings and concentrate by wet magnetic separation after final stage of crushing. Middling is classified to obtain fine and coarse products. Coarse product is crushed at second stage and concentrated to obtain coarse middling and final tailings. Coarse middling is crushed at third stage and concentrated to produce concentrate and final tailings.

EFFECT: higher quality and reduced production costs.

6 cl, 8 dwg, 2 tbl

 

The invention relates to the beneficiation of iron ores and can be used in the mining and metallurgical industry.

There is a method of beneficiation of iron ores, including three stages of grinding, wet magnetic separation of the crushed products of each stage of obtaining tailings and middlings, which are sent to the next stage of grinding. The intermediate magnetic separation before the third stage of grinding directed to the operation of the separation according to the size of the screening with getting small and large product. Underflow rumble sent for separate operation of magnetic separation with receipt of the first concentrate and tailings. Screen oversize is sent for grinding in the third stage and then at the last stage of magnetic separation to obtain a second concentrate and tailings [1]. In the example of realization of the method according to the patent of Russian Federation №2079373 for separation by size is suggested to use hydrocyclones HZ-150, and crushed in the third stage of a major product proposed to be enriched in the magnetic declamatory and gidroseparator to obtain a second concentrate [2].

The disadvantage of this method is its low efficiency caused by the inability of a significant increase in the quality of the first concentrate is rata, derived from the undersize product. This is due to the allocation of rich undersize product just before the last stage of grinding and enrichment without additional grinding. In addition, the second concentrate obtained after grinding and magnetic enrichment, has a lower iron content, which reduces the quality of the total concentrate.

The closest in technical essence to this method is a method of beneficiation of iron ores, including wet grinding of the original ore in three stages, wet magnetic separation of the crushed products of each stage of obtaining tailings and middlings and getting ready concentrate using the wet magnetic separation after the final grinding stage [3]. This method of enrichment is used in almost all zhelezooksidnyh factories and adopted as a prototype. A method of enrichment of iron containing ore (using rod mills in the first stage), adopted as a prototype, is shown in figure 1.

The disadvantage of the prototype, as analogue, is its low efficiency, related to the fact that magnetic product (middlings)obtained after the first grinding stage, containing pure grains of magnetite, rich and poor clusters, comes entirely in the subsequent stage of ismalic the tion, in which grains of magnetite pereselyaetsya and islambeauty. The quality of the concentrate is reduced through the thin sludge rock minerals and large clusters that fall in flocculi formed by particles of magnetite particles rich clusters. In addition, rock particles, both large and small, trapped in flocculi and are not displayed in the final tailings using wet magnetic separation and desliming, get to mill the second and third stages of grinding, which reduces the performance of your grinding and beneficiation plant in General and leads to higher costs of concentrate.

The objective of the invention is to improve the quality iron concentrate (dependent clauses 3, 5 and 6 claims) or a decrease in the cost of the finished concentrate (dependent clauses 2 and 4 of the claims). The first problem can be solved by separation of the product after the first grinding stage on small and large products, and due to subsequent separate grinding of the second and third stages and separate enrichment of small and large products, which provides a more complete disclosure of the ore and rock grains and a more complete conclusion in the final tailings waste particles. The second problem is solved by separation of the product after the first grinding stage on small and large the initial products and due to the subsequent separate grinding of small product in a single stage, as a major product in two stages, which reduces the amount of grinding mills for grinding small product.

This is achieved by a method for beneficiation of iron ores, including three stages of grinding, wet magnetic separation of the crushed products of each stage of obtaining middlings and tailings and production of concentrate by using wet magnetic separation after the final grinding stage, the intermediate after the first grinding stage divided by size to produce small and large products, major product is crushed in the second stage and enrich with obtaining large middlings and tailings, coarse middlings ground in the third stage and enrich with production of concentrate and tailings (figure 2). To reduce the cost of concentrate small product enriched in a separate stage with obtaining middlings and tailings, middlings mixed with large industrial and receive a total product (figure 3) or to improve the quality of the concentrate, small product before enrichment in a separate step, first crushed in a separate second stage (figure 4). The total product is crushed in the third stage and enrich with production of concentrate and tailings (figure 3 and 4). To reduce the cost of concentrate small product smallcat separate second stage and enrich to obtain a second concentrate and tailings (figure 5). To improve the quality of iron concentrate of the second concentrate is ground into a separate third stage, and enrich with obtaining fine-grained concentrate and tailings (6) or the second concentrate divided by size to obtain a second minor and second major products, the second major product is mixed with large industrial and receive a total product that is ground in the third stage and enrich with obtaining the concentrate and tailings, and the second minor product is crushed in a separate third stage, and enrich with high-grade concentrate and tailings (Fig.7).

The separation by size middlings wet magnetic separation after the first grinding stage get smaller and more rich on iron product and a large and more poor iron product (figure 2). This pattern will occur when used in the first stage of the grinding rod mill (open loop), and when used in the first stage of grinding ball mill operating in closed circuit with a classifier. Sieving part of the magnetic product of the operation of wet magnetic separation (MMC) after the first grinding stage with iron content in the classroom size, showing the possibility of increasing the iron content in the fine material, etc is presented in table 1.

Small and richer product obtained after the first stage of grinding and magnetic enrichment, contains pure grains of magnetite intergrowths, therefore, to further obtain from it should concentrate its grinding and enrichment in only one stage. This will reduce pereselenie and alamoana magnetite contained in the shallow and more rich product, and will result in a finished concentrate of small product using only one stage of grinding (dependent clauses 2 and 4 of the claims). This small product can dialogicity in a separate stage of wet magnetic separation (MMS), bypassing the second stage of grinding, to send immediately to the third stage of grinding and enrich together large middlings obtained from the major product after grinding in the second stage and enrichment (dependent claim 2 of the formula of the invention, figure 3). This will reduce the cost of finished concentrate by reducing the number of mills the second stage. Small product can also be crushed only in a separate second stage and to enrich to obtain a second concentrate (dependent claim 4 of the formula of the invention, figure 5). The first concentrate is obtained from a large product. This will reduce the cost of finished concentrate by reducing the number of mills the third is tadie.

To improve the quality of the concentrate, compared with the prototype, small and richer product you need chop in two separate stages and enrich. This small product can be crushed in a separate second stage and enrich, and then sent to the third stage of grinding, together with the large middlings (dependent claim 3 of the formula of the invention, figure 4). Small product can also be mixed in a separate second and third stages and to enrich to obtain a second fine-grained concentrate with a high content of iron (dependent claim 5 claims, 6). The first concentrate is obtained from a large product. The maximum increase in the quality of the concentrate is achieved by grinding small product in a separate second stage and the enrichment of the crushed product to obtain a second concentrate and when you split according to the size of the received second concentrate on the second minor and second major products. The second major product to be poorer than the second minor product. Therefore, the second major product should be combined with large middlings and get the total product. When grinding in a third stage, and the enrichment of the total product obtained concentrate and final tailings. In the second minor product will contain only pure grains of magnetite and some who are rich intergrowths, therefore, it will have a higher iron content compared to the second major product. To obtain a high concentrate of the second minor product must be crushed in a third separate stages and be enriched by wet magnetic separation (dependent claim 5 claims, 7).

Larger and more poor product contains a grain of waste rock and mostly poor intergrowths of magnetite host rocks. When the magnetic enrichment crushed in the second stage of a major product in the diet of the magnetic separator will be small magnetic grains, and they are less likely will contribute to the transition of rock grains in the magnetic product is due to hit rock magnetite particles in flocculi. This will lead to a more complete conclusion in the tails of the particles of waste rock. For complete output in the tails of the particles of waste rock and to obtain major product of concentrate with quality comparable to the quality of the concentrate obtained by the method of enrichment prototype, you have a large product consistently chop in two stages and consistently enriched by wet magnetic separation (figure 2).

The possibility of obtaining a concentrate of small product using one grinding stage and the possibility of improving the quality of concentrate through a rich concentrate of the item is obtainable from small product using two stages of grinding, also due to different grindability of small and large products. Screen characteristics separately milled in a laboratory mill small (-0,63+0 mm), large (-5+0,63 mm) and source (middlings MMC-I after the first grinding stage magnetite ore) products are shown on Fig. The results show that small the product is ground better (β-71=55.6 per cent)than the original (β-71=36,0%) and large (β-71=34,8%) products. The original and major products are crushed almost the same. The result, according to the invention, in comparison with the prototype, the original ore can be crushed to the same size with fewer mills (reducing the cost of concentrate) or the original ore can be crushed to a finer state with the same number of mills (improving the quality of concentrate).

Improving quality iron concentrate or reduce the cost of the concentrate is achieved by using a combination of essential features that characterize the proposed method of enrichment. In the patent and scientific literature, the combination of the above features of the process of beneficiation of iron ore is not found.

In the drawings, is shown in figure 2-7 shows variations of technological schemes for implementing the method.

N the all diagrams (Fig.2-7) shows the implementation of the first stage of grinding in open circuit grinding. In the first grinding stage to use a closed grinding circuit, implemented using a ball mill and classifier. The implementation of the second and third stages of grinding in a closed loop for the various possible schemes, for example through the use of a combined preliminary and verification of classification, or by using a calibration classification, or by using a different schema. In addition, a closed loop can be used in the operation of wet magnetic separation (between mill and hydrocyclone). When this drain mills served in the magnetic separator. Magnetic product separator is directed to the classification in hydrocyclones. The operation of wet magnetic separation (MMC-II) in a closed loop second stages of grinding are shown in all diagrams (Fig.2-7). All diagrams (Fig.2-7) shows the process of ore without desliming operations (declaiming). If the processed ore crushing prone to sliming (as ferruginous quartzite), plum hydrocyclones operations classification of the second and third stages of grinding the wet magnetic separation (MMC-III and MMC-IV) is subjected to a desliming. All diagrams (Fig.2-7) shows the implementation stage of wet magnetic separation in a single operation (for once). Many enrichment of fabricom one stage enrichment is applied several successive operations MMS (multiple techniques). The implementation of individual stages of grinding, the use of additional operations and their number in a particular stage of grinding and enrichment depends on the type and properties of iron containing ore [3, 4]. This does not affect the set of essential features that characterize the proposed enrichment method.

The way of dressing of iron ores according to claim 1 is carried out as follows (figure 2).

Source of iron ore milled in the first stage, for example in an open cycle in the mill, such as MSC, after which the crushed ore is enriched in the first stage of wet magnetic separation by wet magnetic separator, for example, type PBM getting concentrate first stage of wet magnetic separation and tailings. Middlings first stage of wet magnetic separation are divided according to the size of the screen, for example, type "derrick" and get a small (undersize) and large (oversize) products. The major product of the crash crushed the second grinding stage, consisting of mill type MSC, magnetic separators type PBM and hydrocyclone type HZ operating in a closed loop with the mill type MSC. Major product rumble served in the second stage mill type MSC. Unloading mill type MSC the second stage serves in magnetic separators PBM and get middlings second hundred of the AI wet magnetic separation and final tailings. The intermediate second stage of wet magnetic separation is served in the hydrocyclone type HZ with obtaining Sands, which are sent back to the mill type MSC the second stage, and a drain, which is the end product of the second stage of grinding. Crushed in the second stage of a major product screen (drain of the second stage hydrocyclones) is enriched at the third stage of wet magnetic separation by wet magnetic separator type PBM with obtaining large middlings and tailings. Large crushed middlings in the third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. Large middlings served in hydrocyclones type HZ with obtaining Sands, which are sent to the mill type MSC the third stage, and a drain, which is the end product of the third stage of grinding. Unloading mill type MSC third stage serves back into the hydrocyclone type HZ third stage of grinding. Crushed in the third stage of large middlings enrich the fourth stage of wet magnetic separation by wet magnetic separator type PBM with production of concentrate and tailings.

Small product processed by different circuits, depending on solved with the invention of the tasks, in accordance with paragraph 2 of 6 forms of the crystals of the invention (Fig.3-7).

The method according to claim 2 as follows (figure 3).

Small product enriched in a separate third stage of wet magnetic separation by wet magnetic separator, for example, type PBM getting middlings and tailings. Middlings are mixed in the sump with a large middlings and get the total product. The total product is crushed in the third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. The total product is fed into the hydrocyclone type HZ with obtaining Sands, which are sent to the mill type MSC the third stage, and a drain, which is the end product of the third stage of grinding. Unloading mill type MSC third stage serves back into the hydrocyclone type HZ third stage of grinding. Crushed in the third stage of the total product enriched in the fourth stage of wet magnetic separation by wet magnetic separator type PBM with production of concentrate and tailings.

The method according to claim 3 as follows (figure 4).

The fine pulverized product in a separate second grinding stage, consisting of mill type MSC, magnetic separators type PBM and hydrocyclone type HZ operating in a closed loop with the mill type MSC. Small product served in chalk is the Apple of the separate second stage type MSC. Unloading mill type MSC separate second stage serves in magnetic separators PBM and get middlings separate second stage of wet magnetic separation and final tailings. Middlings separate second stage of wet magnetic separation is served in the hydrocyclone type HZ with obtaining Sands, which are sent back to the mill type MSC separate second stage, and a drain, which is the end product of the separate second stage of grinding. Crushed in a separate second stage of small product enriched in a separate third stage of wet magnetic separation by wet magnetic separator type PBM getting middlings and tailings. Middlings are mixed in the sump with a large middlings and get the total product. The total product is crushed in the third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. The total product is fed into the hydrocyclone type HZ with obtaining Sands, which are sent to the mill type MSC the third stage, and a drain, which is the end product of the third stage of grinding. Unloading mill type MSC third stage serves back into the hydrocyclone type HZ third stage of grinding. Crushed in the third stage of the total product enriched in the fourth stage of the IOC is th magnetic separation by wet magnetic separator type PBM with production of concentrate and tailings.

The method according to claim 4 as follows (figure 5).

The fine pulverized product in a separate second grinding stage, consisting of mill type MSC, magnetic separators type PBM and hydrocyclone type HZ operating in a closed loop with the mill type MSC. Small product is fed into the mill a separate second stage type MSC. Unloading mill type MSC separate second stage serves in magnetic separators PBM and get middlings separate second stage of wet magnetic separation and final tailings. Middlings separate second stage of wet magnetic separation is served in the hydrocyclone type HZ with obtaining Sands, which are sent back to the mill type MSC separate second stage, and a drain, which is the end product of the separate second stage of grinding. Crushed in a separate second stage of small product enriched in a separate third stage of wet magnetic separation by wet magnetic separator type PBM to obtain a second concentrate and tailings.

The method according to claim 5 as follows (Fig.6).

The second concentrate is ground into a separate third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. The second concentrate is fed into the hydrocyclone type HZ with obtaining the Sands, refer to the mill type MSC separate third stage, and a drain, which is the end product of a separate third stage of grinding. Unloading mill type MSC separate third stage serves back into the hydrocyclone type HZ separate third stage of grinding. Crushed in a separate third stage of the second concentrate is enriched on a separate fourth-stage wet magnetic separation by wet magnetic separator type PBM with obtaining fine-grained concentrate and tailings.

The method according to claim 6 as follows (Fig.7).

The second concentrate is divided according to the size of the screen, for example, type "derrick" and get a second small (undersize) and second largest (oversize) products. The second major product mix in the sump with a large middlings and get the total product. The total product is crushed in the third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. The total product is fed into the hydrocyclone type HZ with obtaining Sands, which are sent to the mill type MSC the third stage, and a drain, which is the end product of the third stage of grinding. Unloading mill type MSC third stage serves back into the hydrocyclone type HZ third stage of grinding. Change Jenny in the third stage of the total product enriched in the fourth stage of wet magnetic separation by wet magnetic separator type PBM with production of concentrate and tailings. The second minor product is crushed in a separate third stage of grinding, consisting of mill type MSC and hydrocyclone type HZ operating in a closed loop with the mill type MSC. Small product is fed into the hydrocyclone type HZ with obtaining Sands, which are sent to the mill type MSC separate third stage, and a drain, which is the end product of a separate third stage of grinding. Unloading mill type MSC separate third stage serves back into the hydrocyclone type HZ separate third stage of grinding. Crushed in a separate third stage small product enriched in a separate fourth stage of wet magnetic separation by wet magnetic separator type PBM with high-grade concentrate and tailings.

If the original iron ore presents ferruginous quartzites or other ores, prone to sliming during grinding, plum hydrocyclones all stages of grinding additionally bessellieu through declamation, for example, type MD.

Experimental verification of the proposed method performed in laboratory conditions for magnetite ores. Comparative indicators of enrichment for the proposed method and the prototype are given in table 2. The results of the experiments showed that the proposed CSP is both allows comparison with the prototype to increase the iron content in the total concentrate of 2.50-2.78% rate while maintaining the volume of shredding equipment (dependent clauses 3, 5 and 6 claims) or of 1.40 was 1.69%, while reducing the amount of grinding equipment (dependent clauses 2 and 4 of the claims). The method according to claim 6 allows, as one concentrates to obtain high-quality concentrate containing iron and silica 67,1 and 0.96%, respectively.

An example of the method for beneficiation of iron ore according to claim 1 applied to magnetite ore (figure 2).

The original ore with an iron content of 15.6% crushed in the first stage of grinding in an open cycle in rod mill MSC-3600×4500 particle size up to 19.4% of the class -0,071 mm and served in magnetic separators PBM-P-150/200 first stage of magnetic separation to obtain the concentrate with iron content of 28,09% and tailings from the iron content 6,04%. Middlings first stage of wet magnetic separation serves to rumble "derrick" type 2SG48-60W-5STK the size of the holes of the sieve of 0.5 mm to produce small (undersize) product with an iron content 38,15% and large (oversize) product with an iron content 21,18%. The major product is crushed in the second grinding stage, consisting of mills MSC-3600×4500, wet magnetic separators PBM-P-150/200 and hydrocyclones HZ-710 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-710 size 74.9% class -0,071 mm and a content of iron 43,73%, Atwal who's tails separators PBM-P-150/200 with iron content 6,11%. The drain of the second stage hydrocyclones grinding served on the third stage of wet magnetic separation in the separator PBM-PP-150/200 obtaining major concentrate with iron content of 59.1 per cent and tailings with an iron content of 6.8%. Large crushed middlings in the third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500; obtaining plum hydrocyclones HZ-500 size 92.7% of class -0,071 mm and an iron content of 59.1 per cent. The drain of the third hydrocyclone stage grinding served on the fourth stage of wet magnetic separation in the separator PBM-PP-150/200 getting a concentrate with iron content of 63.4 per cent and tailings with an iron content of 8.3%.

An example implementation of the method according to claim 2 (figure 3).

Small product serves to separate the third stage of wet magnetic separation in the separator PBM-PP-150/200 getting concentrate with iron content of 47.6% and tailings with an iron content of 6.1%. Middlings separate operations MMC-III and a large middlings served in the sump, where the mixing of these products. In total product contains 51.6 per cent of iron. The total product is crushed in the third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500, obtaining discharge of gidrol lonow HZ-500 size 92.3% of class -0,071 mm and an iron content of 51.6%. The drain of the third hydrocyclone stage grinding served on the fourth stage of wet magnetic separation in the separator PBM-PP-150/200 getting a concentrate with an iron content of 63.7% and tailings with an iron content of 6.58 percent.

An example implementation of the method according to claim 3 (figure 4).

The fine pulverized product in a separate second grinding stage, consisting of mills MSC-3600×4500, wet magnetic separators PBM-P-150/200 and hydrocyclones HZ-710 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-710 size 81,2% class -0,071 mm and an iron content of 53.1 per cent and tailings separators PBM-P-150/200 with an iron content of 6.2%. Drain hydrocyclones separate second grinding stage serves to separate the third stage of wet magnetic separation in the separator PBM-PP-150/200 getting concentrate with iron content of 64.4% and tailings with an iron content of 6.9%. Middlings separate operations MMC-III and a large middlings served in the sump, where the mixing of these products. In total product contains 62,12% iron. The total product is crushed in the third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-500 size 94.5% of class -0,071 mm and a content of iron 62,12%. Plums guy is recyclenow the third stage of grinding is served on the fourth stage of wet magnetic separation in the separator PBM-PP-150/200 getting a concentrate with iron content of 64.8 per cent and tailings from the iron content 8,65%.

An example implementation of the method according to claim 4 (figure 5).

The fine pulverized product in a separate second grinding stage, consisting of mills MSC-3600×4500, wet magnetic separators PBM-P-150/200 and hydrocyclones HZ-710 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-710 size 81,2% class -0,071 mm and an iron content of 53.1 per cent and tailings separators PBM-P-150/200 with an iron content of 6.2%. Drain hydrocyclones separate second grinding stage serves to separate the third stage of wet magnetic separation in the separator PBM-PP-150/200 to obtain a second concentrate with iron content of 64.4% and tailings with an iron content of 6.9%. In total concentrate consisting of a concentrate obtained from major product and the second concentrate, contains 63,99% of iron.

An example implementation of the method according to claim 5 (6).

The second concentrate is ground into a separate third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-500 size 96.7% of class -0,071 mm and an iron content of 64.4 per cent. Drain hydrocyclones separate third stage of grinding is served on the fourth single stage wet magnetic separation in the separator PBM-PP-150/200 obtaining fine-grained concentrate with soda is the content of iron to 66.3% and tailings with an iron content of 17.9%. In total concentrate consisting of a concentrate obtained from major product and fine-grained concentrate, contains 65,08% of iron.

An example implementation of the method according to claim 6 (Fig.7).

The second concentrate serves to rumble "derrick" type 2SG48-60W-5STK with a hole size of 0.1 mm sieve to obtain a second small (undersize) product with an iron content of 65.2% and the second largest (oversize) product with an iron content 61,76%. The second major product and a large middlings served in the sump, where the mixing of these products. In total product contains 59,73% iron. The total product is crushed in the third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-500 size 93.8% class -0,071 mm and a content of iron 59,73%. The drain of the third hydrocyclone stage grinding served on the fourth stage of wet magnetic separation in the separator PBM-PP-150/200 getting a concentrate with an iron content of 63.1% and tailings with an iron content of 19.5%. The second minor product is crushed in a separate third stage of grinding, consisting of mills MSC-3600×4500 and hydrocyclones HZ-500 operating in a closed cycle mill MSC-3600×4500, obtaining plum hydrocyclones HZ-500 size 98,9% class -0,071 mm and the content is the use of iron to 65.2%. Drain hydrocyclones separate third stage of grinding is served on the fourth single stage wet magnetic separation in the separator PBM-PP-150/200 with high-grade concentrate with iron content of 67.1% and tailings from the iron content 18,21%. In total concentrate consisting of a concentrate obtained from the largest and second largest products and high quality concentrate, contains 64,89% of iron.

Implementation of the proposed method in comparison with the prototype allows the separation by size of concentrate after the first grinding stage to increase the iron content in the total concentrate of 2.50-2.78% rate while maintaining the volume of shredding equipment, or of 1.40 was 1.69%, while reducing the amount of grinding equipment. It is possible, as one concentrates to obtain high-quality concentrate containing iron and silica 67,1 and 0.96%, respectively.

Sources of information

1. Zhuravlev, S. Enrichment of magnetite ores contact - and hydro-thermal and metasomatic Genesis. M.: Nedra, 1978, S. 115-119, 39, scheme 1.

2. RF patent №2079373. The way of dressing of iron ores. Authors: Azamatov IVAN, Azamatov FL, Dremin A.I. and other Publ. 20.05.1997.

3. Ostapenko P.E. Theory and practice enrichment of iron ore. M.: Nedra, 1985, s-177.

4. Reference obog is the ore. Concentrator / Under. edit Ostrodumov, Û.F. Nenarokomov. 2nd ed., Rev. and ext. M.: Nedra, 1984. 358 C.

Table 1
The results of fractionation by size of middlings MMC-I after the first grinding stage
Class size, mmOutput %The iron content, %Iron extraction, %
Magnetite quartzite, ball mill and spiral classifier in the first stage of grinding, vicious cycle
+0,225,229,015,2
-0,2+0,113,744,6a 12.7
-0,1+0,0718,253,09,1
-0,071+0,04516,656,919,7
-0,045+036,357,243,3/td>
Only100,0048,0100,00
Magnetite ore rod mill in the first grinding stage, open circuit
+1,2527,020,6120,97
-1,25+0,6326,0to 21.1520,72
-0,63+0,31521,025,93to 20.52
-0,315+0,1613,034,0816,69
-0,16+0,16,043,609,86
-0,1+0,0713,048,705,50
-0,071+04,038,105,74
Only10026,54100,00

Table 2
Results enrichment of the prototype and the proposed method
ProductOutput %The iron content, %Iron extraction, %
Prototype 1
Concentrate16,8962,3067,45
Tails83,116,11worth 32.55
The original ore100,0015,60100,00
The proposed method according to claim 1, 2
Small17,6538,1543,16
Concentrate6,7063,4027,23
Tails75,656,11to 29.61
The original ore 100,0015,60100,00
The proposed method according to claim 2, 3
Concentrate16,4763,7067,25
Tails83,536,1232,75
The original ore100,0015,60100,00
The proposed method according to claim 3, 4
Concentrate16,1264,8066,96
Tails83,886,1433,04
The original ore100,0015,60100,00
The proposed method according to claim 4, 5
Concentrate6,7063,4027,23
The second concentration is 9,6664,4039,88
Total concentrate16,3663,9967,11
Tails83,646,1332,89
The original ore100,0015,60100,00
The proposed method according to claim 5, 6
Concentrate6,7063,4027,23
Fine-grained concentrate9.28 areto 66.3039,44
Total concentrate15,9865,0866,67
Tails84,02to 6.1933,33
The original ore100,0015,60100,00
The proposed method according to claim 6, 7
Concentrate8,7863,1035,51
High quality concentrate7,1267,1030.63 per
Total concentrate15,9064,8966,14
Tails84,106,2833,86
The original ore100,0015,60100,00

1. The way of dressing of iron ores, including three stages of grinding, wet magnetic separation of the crushed products of each stage of obtaining middlings and tailings and production of concentrate by using wet magnetic separation after the final grinding stage, characterized in that the intermediate after the first grinding stage divided by size to produce small and large products, major product is crushed in the second stage and enrich with obtaining large middlings and tailings, coarse middlings and is hollowed out in the third stage and enrich with production of concentrate and tailings.

2. The method according to claim 1, characterized in that the small product enriched in a separate stage with obtaining middlings and tailings, middlings mixed with large industrial and receive a total product that is ground in the third stage and enrich with production of concentrate and tailings.

3. The method according to claim 2, characterized in that the small product before enrichment in a separate step, first crushed in a separate second stage.

4. The method according to claim 1, characterized in that the fine pulverized product in a separate second stage and enrich to obtain a second concentrate and tailings.

5. The method according to claim 4, characterized in that the second concentrate is ground into a separate third stage, and enrich with obtaining fine-grained concentrate and tailings.

6. The method according to claim 4, characterized in that the second concentrate divided by size to obtain a second minor and second major products, the second major product is mixed with large industrial and receive a total product that is ground in the third stage and enrich with obtaining the concentrate and tailings, and the second minor product is crushed in a separate third stage, and enrich with high-grade concentrate and tailings.



 

Same patents:

FIELD: process engineering.

SUBSTANCE: invention relates to extraction and processing of heavy minerals from hard-cleaning ore and complex alluvial deposits with increased content of fine and thin gold in intergrowths. Proposed method comprises opening mineral grain by wave attack. Intergrowths are destructed by electromagnetic field generating ultrasound wavelength being multiple of quartz grain h at the ratio of (2-3)Λ:h, and radiation intensity allowing transformation of electromagnetic polarisation into elastic deformation of variable strain in intergrowths of gold ore concentrate intergrowths at consecutive effects of ultrasound along and across intergrowth. Note here that concentrate surface heating temperature may not exceed that of phase changes of mineral inclusions while concentrate layer thickness may not exceed the range of radiation intensity attenuation by more than two times.

EFFECT: higher yield and efficiency, ecological safety.

2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to mining, concentration of minerals and may be used for dressing of minerals. Proposed device consists of conveyor rubberised fabric belt fitted on drive and driven drums, drives, magnetic system of permanent magnets, frame, and suspension bath. Magnetic system arranged above conveyor lower flight is provided with straight rolls mounted at its lower section to rest on bearings. Suspension bath loading side features superficial rectangle arranged all over the length of magnetic system and inclined along suspension transfer through 1° to change into deep chute with length two times larger than bath rectangular section with inclination 15°.

EFFECT: higher efficiency and quality, reduced costs.

2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to classification of solids with the help of fluids and may be used in concentration of minerals, etc. Proposed method comprises loading fluid with raw stock onto inclined trough top with irregularities arranged on its edges, creating directed flow of pulp by restricting pump flow height at bottom of said inclined trough using overhead cover arranged above said irregularities and directing main pulp flow upward via discharge tube, separating raw stock particles into fractions using reciprocation of working surface with sharp accelerations, discharging obtained fractions at working surface bottom and selecting optimum conditions of classification. Overhead cover arranged above aforesaid irregularities is provided with magnetic fraction accumulator. Outlet is arranged sideways of irregularities provided with magnetically conductive tube to displace magnetic fraction in appropriate accumulator. Magnets are secured above said overhead cover to force mixing of powder material and displacing it toward aforesaid outlet and, therefrom, into aforesaid accumulator.

EFFECT: higher quality of classification.

1 dwg, 2 ex

FIELD: process engineering.

SUBSTANCE: invention relates dressing of minerals and may be used for extraction of fine conducting particles, e.g. gold, silver, platinoids from metal-containing gravel deposits of various genesis. Proposed method consists in that single magnetic field pulses are generated to shape travelling magnetic field pulse groups. Note here that said pulses are synchronised in said group while pulse amplitude and group repetition rate are selected to ensure required extraction of valuable particles from bulk flow.

EFFECT: higher efficiency, power savings, expanded range of extracted particles.

4 cl, 4 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to magnetic concentration of ores. Proposed method consists in subjecting pump to effects of variable magnetic field with decreasing amplitude to demagnetise and destruct magnetic floccules. Pulp processing is performed by variable magnetic field with decreasing amplitude in direction of pulp displacement in the presence of permanent magnetic field directed perpendicular at increasing intensity.

EFFECT: higher quality of magnetic concentrate.

2 cl, 1 dwg

FIELD: process engineering.

SUBSTANCE: invention may be used in preparation of ores and industrial wastes for concentration and other types of processing. Proposed methods comprises processing material containing ferromagnetic components by magnetic field pulses. Material lump is loaded in vertical coil while coil winding is connected to electric current pulse source to generate magnetic field pulses to pull magnetic lumps inside coil for them to collide. Method includes combining, in time and space, the effects of mechanical strains generated by collisions and effects of magnetism (inductive, magnetistrictive, magnetothermal, Villary, Eistein-de-Haas) that enhance probability of crack formation on boundaries of ferromagnetic and nonmagnetic components and selectivity of softening and disintegration in magnetic-and-mechanical processing at the following ratio: lk/n+Δ=vft+gt2/2 where lk is coil length, n is number of pulses processing ore column with length lk, Δ is distance between device to feed ore in coil and coil top, vf is initial rate of raw stock particles fed into coil, g is gravity, t is time ore particles PASS from feeder to coil bottom (Δ+1k).

EFFECT: higher quality of processing.

1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to gold mining for concentration of fine gold in primary collective concentrates containing magnetic minerals and may be used at slime concentration units of gold fields and concentration plants. Proposed device comprises continuous loading and unloading, magnetic mineral separation chamber and made up of vertical rectangular container, nonmagnetic mineral separator and special-design splitter. To separate magnetic mineral from primary collective concentrates, movable metal case with permanent magnets is arranged on all four sides of vertical nonmagnetic chamber to remove force magnetic minerals from chamber walls to 70-100 mm therefrom and wash them off. Thereafter, metal case is again pressed against the chamber. Note here that aforesaid splitter is made up of quadrangular truncated pyramid.

EFFECT: higher efficiency.

1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to magnetic dressing of ores. Proposed method comprises extracting magnetic mineral grains from pump, carrying them by rotary nonmagnetic drum relative to permanent magnets arranged inside said drum that have magnetic polarity alternating in direction of rotation. Note here that floccules swing without separation from drum surface for partial separation of nonmagnetic inclusions. Magnetic system ensures periodical separation of magnetic fraction from drum surface in radial direction, hence, intensive destruction of magnetic floccules and efficient cleaning of magnetic concentrate from nonmagnetic impurities.

EFFECT: higher quality of concentrate.

2 cl, 1 dwg

FIELD: process engineering.

SUBSTANCE: proposed method relates to magnetic separation of fluid or dust-gas products with fine low-magnetic admixtures and may be used in ceramics, power engineering, pharmaceutics, mining, etc. Proposed method comprises passing the product to be separated through array filter 5 fitted in case 4 and made from ball-shaped ferromagnetic granules located in magnetic field of magnetic system 6 made up of permanent magnets, depositing product magnetic fraction particles on array filter granules, terminating magnetic field effect by moving array filter filled with sediment from magnetic field, breaking the structure of array filter and contacts between adjacent granules by mechanical means, cleaning filter of deposited product particles by rinsing with water or blowing by compressed air. Aforesaid moving from magnetic field, removing contacts between granules and cleaning granule surfaces of deposits are carried out by centrifugal forces brought about by tapered flow case arranged vertically and having its side surface at acute angle to vertical.

EFFECT: simplified design, optimised magnetic filter, higher efficiency of separation.

7 cl, 4 dwg

Magnetic separator // 2440852

FIELD: process engineering.

SUBSTANCE: invention relates to magnetic separation of sold materials from fluids, namely, to magnetic separators with material cylindrical drives and may be used in separation of emulsions and suspensions. Magnetic separator comprises feeding and discharging channels for magnetic and nonmagnetic materials, working member made up of inner and outer cases made from nonmagnetic materials, device to separate flow into magnetic and nonmagnetic fractions, and filter element from ferromagnetic. Filtration element is made up of two aligned spirals made from magnetically soft ferromagnetic different-diameter wires with pitch equal to 3-5 wire diameters wound on outer surface of inner case and buried flush with case surface to produce induction of disturbed magnetic field flow with high radial gradient in formed clearance between cases of magnetic system.

EFFECT: higher efficiency, decreased overall dimensions and weight.

2 dwg

Magnetic separator // 2245194

FIELD: separation of materials by magnetic properties; concentration of ferrous metal ores.

SUBSTANCE: proposed magnetic separator includes feeder, bath, loading channel for initial pulp and unloading channels for magnetic and non-magnetic products and working member in form of non-magnetic drum with magnetic system arranged inside it; this magnetic system includes main and additional permanent magnets at alternating polarity. Additional permanent magnets are located between main permanent magnets mounted above unloading channel used for non-magnetic product and main permanent magnets are located above loading channel; they have integral monopolar surface closing the said loading channel.

EFFECT: enhanced efficiency of magnetic separation.

1 dwg

FIELD: concentration of minerals by magnetic separation.

SUBSTANCE: proposed separator includes magnetic system located under moving belt of conveyer around vertical axis; magnetic system consists of permanent magnets at alternating polarity over circle arc. Revolving magnetic system is located above moving belt of conveyer and distance between belt and inclination of axis of rotation may be changed vertically; magnetic fraction is unloaded by means of non-magnetic disk rotating together with magnetic system; this disk is located under magnetic system for change of distance to magnets.

EFFECT: selective separation of product into magnetic fractions in extensive range of their susceptibility.

2 dwg

FIELD: concentration of minerals by magnetic separation.

SUBSTANCE: proposed separator includes magnetic system located under moving belt of conveyer around vertical axis; magnetic system consists of permanent magnets at alternating polarity over circle arc. Revolving magnetic system is located above moving belt of conveyer and distance between belt and inclination of axis of rotation may be changed vertically; magnetic fraction is unloaded by means of non-magnetic disk rotating together with magnetic system; this disk is located under magnetic system for change of distance to magnets.

EFFECT: selective separation of product into magnetic fractions in extensive range of their susceptibility.

2 dwg

FIELD: mineral dressing.

SUBSTANCE: invention concerns production of iron-titanium-vanadium concentrates from corresponding complex ores for subsequent metallurgical processing. Method comprises crushing original ores followed by dry magnetic separation. Crushing involves opening of combined junctions of titanium-magnetite-ilmenite with silicate minerals and is carried out to achieve fineness from 50 to 15 mm. Dry magnetic separation is effected at magnetic field intensity 40 to 120 kA/m, specific productivity from 50 to 100 t/h per 1 m length of magnetic separator drum, and moisture of ore being concentrated from 3 to 5% resulting in isolation of combined titanium-magnetite-ilmenite concentrate into magnetic fraction for succeeding smelting to produce vanadium-containing cast iron and high-titanium slags for production of titanium dioxide.

EFFECT: enhanced process efficiency.

1 dwg, 1 tbl

Separator // 2249486

FIELD: equipment for concentration (separation) of fine-dispersed mixtures, in particular, mining industry, for enrichment of iron-ore concentrates.

SUBSTANCE: separator has casing, charging device, discharge device, and magnet with pole tip. Casing is made hermetically sealed. Hopper fixed in casing upper part is equipped with discharge window arranged in lower part of hopper front wall. Chute fixed under hopper is formed as flat hollow member with upper cover made from metal ceramics permeable for working fluid and lower cover made from high-strength material. Chute is positioned so as to be vibrated perpendicular to displacement vector of mixture under separation process. Chute cavity is communicated with working fluid source. Magnet is fixed to casing wall so as to be adjustably moved in vertical plane. Pole tip working side is made arced. Screen arranged between pole tip and mixture under separation process is made in the form of flat hollow member curved along arc of circle with center offset in vertical plane relative to center of circle of pole tip. Flat hollow screen has outer cover made from metal ceramics permeable for working fluid and inner cover made from non-magnetic high-strength material and connected in sealing relationship with outer cover. Screen is movably attached to casing wall for vibration perpendicular to displacement vector of mixture under separation process. Screen cavity is communicated with working fluid source. Discharge devices are made in the form of outlets equipped with sluice gates.

EFFECT: increased capacity and improved quality of extraction in polygradient mode of operation.

2 dwg

FIELD: agricultural mechanical engineering.

SUBSTANCE: proposed method includes action on grain blend suspended in air space by electric field of corona discharge and electrostatic electric field. Grain blend preliminarily separated in electric field is additionally acted on by magnetic field which is sectionalized into separate sections whose independent axes are shifted in horizontal plane relative to one another. Direction of action of magnetic fields is so selected that forces of magnetic field acting on seeds should coincide with direction of action of forces of electric field.

EFFECT: improved quality of separation and treatment; increased productivity.

2 cl

FIELD: agricultural mechanical engineering.

SUBSTANCE: proposed device includes bin, system of electrodes for forming corona and electrostatic sections of electric field and tray for grain fractions. Device is also provided with grain flow control unit, electromagnet for additional separation of blend mounted in zone of falling of charged grain preliminarily separated by electric field below electrodes creating electrostatic section and electromagnet position regulator. Electromagnet is made in form of separate sections having independent magnetic axes. Electromagnet sections are mounted at shift of their magnetic axes in horizontal plane relative to each other so that direction of electric and magnetic forces acting on freely falling grain should coincide in direction and be maximum.

EFFECT: improved quality of separation; increased productivity.

2 cl, 1 dwg

FIELD: mining; dressing of minerals with the help of a method of magnetic separation of pulps.

SUBSTANCE: the invention is pertaining to the field of dressing of minerals f minerals with the help of a method of magnetic separation of fine-dispersed pulps, selective separation by magnetic properties of the finely dispersed dry magnetic powder mineral mixtures. The technical result is combining of an effective breaking- down of magnetic pudding stones and floccules with a high selectivity of magnetic separation of fine pulps and finely-dispersed dry magnetic powder mineral mixtures. The separator contains a magnet system, which has been made out of permanent magnets capable to rotate with a regulated frequency. The magnet system is made out of three layers of permanent magnets: a central layer - with magnets in the form of rectangular prisms, additional layers - with magnets in the form of the truncated prisms. The separator is also equipped with a lateral separating chamber with a movable gate separating an area of a demagnetization and breaking-down of the magnetic floccules from an area of additional purification and separation with a capability of separation of mineral mixtures both in the form of fine pulps and in a dry state.

EFFECT: the invention ensures a combining of an effective breaking-down of magnetic pudding stones and floccules with a high selectivity of magnetic separation of the fine pulps and finely-dispersed dry magnetic powder mineral mixtures.

1 dwg

FIELD: separation of finely divided mechanically prepared mixtures containing magnetic fractions.

SUBSTANCE: separator includes apparatus for feeding raw material, unit for separating raw material in the form of plate with three-phase winding, trough with ferromagnetic layer in bottom mounted on elastic members. When apparatus for feeding raw material realizes working process of metering material, mechanically prepared mixture is fed in trough that performs rocking due to change of magnetic induction. Due to action of pondermotive forces magnetic particles float up to surface of layer moving downwards, they move towards traveling magnetic field and enter pipeline for products. Unit for separating raw material and trough are arranged by inclination angle α relative to horizontal plane. Inclination angle of trough and rigidity of elastic members may be adjusted.

EFFECT: enhanced quality of separation process.

2 dwg

FIELD: separation of finely divided mechanically prepared mixtures containing magnetic fractions.

SUBSTANCE: separator includes apparatus for feeding raw material, unit for separating raw material in the form of plate with three-phase winding, trough with ferromagnetic layer in bottom mounted on elastic members. When apparatus for feeding raw material realizes working process of metering material, mechanically prepared mixture is fed in trough that performs rocking due to change of magnetic induction. Due to action of pondermotive forces magnetic particles float up to surface of layer moving downwards, they move towards traveling magnetic field and enter pipeline for products. Unit for separating raw material and trough are arranged by inclination angle α relative to horizontal plane. Inclination angle of trough and rigidity of elastic members may be adjusted.

EFFECT: enhanced quality of separation process.

2 dwg

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