Comprehensive utilization method of ultra-lean vanadium titano-magnetite tailings

Abstract

The invention relates to a comprehensive utilization method of ultra-lean vanadium titano-magnetite tailings, and belongs to the field of comprehensive utilization of solid wastes. According to the method, the purpose of resource utilization of solid waste is achieved through comprehensive utilization of the ultra-lean vanadium titano-magnetite tailings, elements such as Si and Al in the tailings are enriched while the phosphate concentrate with the grade and the recovery rate meeting production requirements is obtained, consumption of a large amount of tailings is achieved, the environment and safety problems caused by stacking of the tailings are solved, and the utilization rate of the tailings is increased. And the technical purpose of comprehensive utilization of solid wastes is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of comprehensive utilization of solid wastes, and in particular to a comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings. Background Art

[0002] Vanadium-titanium magnetite is a composite mineral resource containing metals such as iron, titanium and vanadium. my country's vanadium-titanium magnetite resources are mainly concentrated in Panzhihua, Sichuan and Chengde, Hebei. The Chengde area of ​​Hebei is mainly dominated by ultra-poor vanadium-titanium magnetite, with reserves exceeding 10 billion tons. Its mineral composition is complex and contains a large number of associated minerals. In addition to iron minerals, it also contains valuable elements such as phosphorus. However, the intercalation relationship between vanadium-titanium magnetite minerals is relatively complex, and the ore structure and mineral structure are diverse, which makes it difficult to effectively recover the phosphorus-containing resources and enter the tailings, resulting in serious waste of resources. In addition, the discharge of a large amount of vanadium-titanium magnet tailings also causes environmental pollution.

[0003] At present, the depletion of phosphorus resources has become a global problem. How to develop the source of phosphorus resources is an urgent task to solve the current shortage of phosphorus resources; and the disposal and consumption of vanadium-titanium magnet tailings has also attracted widespread attention. Therefore, in view of the current status of resources and environment, the research on phosphorus selection and comprehensive utilization of low-grade vanadium-titanium magnet tailings is of great significance to improve resource utilization, reduce environmental burden, and promote the sustainable development of phosphorus chemical industry and mining industry. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for comprehensive utilization of ultra-poor vanadium-titanium magnetite tailings, which adopts a method of first magnetic and then flotation to recover phosphorus resources in the tailings, and uses the magnetic products and phosphorus-selected tailings as building materials to produce unburned bricks, thereby realizing the comprehensive resource utilization of vanadium-titanium magnetite tailings.

[0005] To achieve this technical purpose, the present invention adopts the following scheme:

[0006] The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings comprises the following steps:

[0007] S1. Grinding the ultra-poor vanadium-titanium magnetite tailings;

[0008] S2, the ground pulp is subjected to wet weak magnetic separation to pre-select tailings to obtain non-magnetic products and magnetic products. The magnetic products are used as unburned aggregates, and the non-magnetic products are subjected to flotation;

[0009] S3, slurrying the non-magnetic product to obtain flotation pulp, and sequentially adding a regulator, a depressant, and a collector to the flotation pulp to perform positive flotation of phosphorus. The flotation process includes one roughing, one scavenging, and four cleaning processes to obtain phosphate concentrate and phosphate tailings;

[0010] S4. The phosphate tailings and the magnetic product are mixed to obtain aggregates for unburned bricks, and the unburned bricks are obtained through drying, batching, molding and curing.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention adopts the underflow of ultra-poor vanadium-titanium magnetite tailings after being treated by a thickener as raw material, further performs grinding treatment on the tailings, and then uses a weak magnetic separation process to remove part of the weak magnetic products, and the obtained non-magnetic ore is used as phosphorus flotation feed; the phosphorus flotation feed is slurried to obtain flotation operation slurry, and pH adjuster sodium carbonate, dispersant and inhibitor water glass, and collector fatty acid collector are added to the slurry in sequence to perform phosphorus positive flotation, thereby obtaining phosphate concentrate and phosphorus tailings; and then the comprehensive tailings mixed with the weak magnetic products and the phosphorus tailings are used to prepare unburned bricks, which not only realizes the disposal of bulk tailings, solves the environmental and safety problems caused by tailings stacking, but also achieves the technical purpose of comprehensive utilization of solid waste.

[0012] Furthermore, the grinding in S1 requires that the minerals with a particle size of -0.074 mm account for 60% to 90% of the mass fraction of the original ore.

[0013] Furthermore, the S2 wet weak magnetic separation is 240~350kA / m.

[0014] Furthermore, the adjusting agent in S3 is sodium carbonate, and the dosage is 0 to 2000 g / t.

[0015] Furthermore, the inhibitor in S3 is water glass, and the dosage is 0-1000 g / t, and more preferably, the dosage is 0-600 g / t.

[0016] Furthermore, the collector in S3 is a composite agent (FAB) composed of a fatty acid collector and a surfactant with anti-low-temperature effect, and its composition is sodium oleate: sodium petroleum sulfonate: polyethanol monomethyl ether (MPEG-200) = 70:20:10, and the dosage is 100-400g / t, and the more preferred dosage is 300-400g / t.

[0017] Furthermore, during the roughing process, the regulator, inhibitor and collector are added in sequence. Each agent is fully stirred after being added before the next agent is added. After the collector is added and stirred, the foam is scraped for 4 to 6 minutes to obtain a rough concentrate. The product in the tank is the scavenging feed.

[0018] During the scavenging process, continue to add collectors in an amount of 100-300 g / t, fully stir, scrape and foam for 4-6 minutes to obtain phosphorus ore and phosphorus tailings;

[0019] During the selection process, water glass was added at 0-600g / t in the first three selections. No reagent was added in the fourth selection. After sufficient stirring, scraping and bubbling began. The scraping and bubbling times for the four selections were 4-6min, 2-3min, 1.5-2.5min, and 1.0-2.0min respectively. Phosphate concentrate was obtained in the fourth selection, and the concentrate tailings from each level of selection were returned to the previous level of selection operation.

[0020] Further, drying in S4: filtering the mixture of the magnetic product and the phosphate tailings to remove moisture, and drying in an oven at 105° C. for 24 hours to obtain unburned brick aggregate;

[0021] Ingredients: Mix unburned brick aggregate, cement, lime, triethanolamine and polycarboxylate water reducer in proportion, and stir the mixture repeatedly with a stirrer;

[0022] Molding: Fill the mixed material into the mold and use the static pressure process of the press to form the brick embryo;

[0023] Curing: After demoulding, the brick embryo is naturally cured in a curing box to obtain tailings unfired brick samples.

[0024] Furthermore, the brick embryo curing temperature is 20±2°C and the humidity is 90%.

[0025] The above-mentioned "g / t" refers to the amount of flotation reagent added relative to the amount of ore fed. For example, if the amount of water glass added is 500g / t, it means that 500g of water glass needs to be added to process 1 ton of tailings.

[0026] Compared with the existing technology, the present invention has the following advantages:

[0027] (1) In order to extract phosphorus resources from ultra-depleted vanadium-titanium magnetite tailings, the present invention adopts weak magnetic separation-flotation separation to extract phosphorus from tailings, considering the low phosphorus grade in the tailings. Compared with full flotation, the cost is significantly reduced. Under the optimal conditions, the P2O5 grade in the phosphate concentrate is greater than 35%, and the recovery rate is greater than 80%;

[0028] (2) In view of the significant increase in silicon and aluminum content in the tailings after strong magnetic separation-flotation treatment, the scavenging tailings and magnetic separation products are directly used as building materials for the production of unburned bricks. The physical properties of the unburned bricks obtained meet the standard requirements of MU15 grade in "Non-burned Waste Tailings Bricks" (JC / T422-2007);

[0029] (3) In the technical solution provided in this proposal, by strictly controlling the process parameters, while ensuring the grade and yield of phosphate concentrate, it also provides raw materials for subsequent use in building materials. This not only realizes the disposal of large amounts of tailings, but also improves resource utilization and promotes the sustainable development of the mining industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A process flow chart of a comprehensive utilization method of ultra-depleted vanadium-titanium magnetite tailings provided by the present invention. DETAILED DESCRIPTION

[0031] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific implementation methods, but the present invention is not limited thereto.

[0032] Example 1

[0033] Taking the ultra-poor vanadium-titanium magnetite tailings from a certain place as raw material, the properties and particle size composition of the tailings are shown in Tables 1 and 2.

[0034] Table 1 Main chemical composition of a super-poor vanadium-titanium magnetite tailings

[0035] chemical composition TFe mxD <![CDATA[P2O5]]> <![CDATA[TiO2]]> <![CDATA[Al2O3]]> <![CDATA[SiO2]]> <![CDATA[Na2O]]> <![CDATA[K2O]]> MgO CaO content / % 8.10 0.56 1.52 1.91 8.88 40.98 1.12 0.96 12.02 18.47

[0036] Table 2 Particle size distribution of tailings of a super-poor vanadium-titanium magnetite ore

[0037] Particle size / mm Weight / kg Yield / % Cumulative yield / % +3 0.04 0.73 0.73 -3+2 0.02 0.36 1.09 -2+1 0.10 1.82 2.91 -1+0.7 0.08 1.46 4.37 -0.7+0.5 0.58 10.56 14.94 -0.5+0.3 0.74 13.48 28.42 -0.3+0.2 0.62 11.29 39.71 -0.2+0.1 1.16 21.13 60.84 -0.1+0.074 0.36 6.56 67.40 -0.074 1.79 32.60 100.00

[0038] The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings has the following steps:

[0039] S1. Using the above tailings as raw materials, the tailings were ground in a ball mill with a grinding concentration of 50% and a grinding time of 5 minutes to obtain a grinding product with a -0.074mm content of 80%.

[0040] S2. The ground ore product obtained in S1 is subjected to magnetic separation and tailings removal, and the magnetic field strength is 240 kA / m to obtain magnetic products and non-magnetic products. The magnetic products are used as building materials, and the non-magnetic products are used as phosphorus flotation feed.

[0041] S3, the phosphorus flotation feed obtained in S2 is subjected to positive flotation of phosphorus. The flotation process includes one roughing, one sweeping and four refining steps. The phosphorus feed is first slurried, and the slurry concentration is 35%.

[0042] The phosphorus roughing reagent system is: 1000g / t sodium carbonate, stir for 2 minutes, add 400g / t water glass, stir for 2 minutes, add 300g / t FAB, stir for 2 minutes, and scrape and foam for 4 minutes.

[0043] The phosphorus sweeping agent system is: 100g / t FAB, stirring for 2min, scraping and foaming for 4min.

[0044] The reagent system for phosphorus concentration is as follows: 400g / t of water glass is added in the first, second and third concentration operations respectively, and the fourth concentration is a blank concentration. The stirring is 2min, and the scraping time is 4min, 2min, 1.5min and 1.0min respectively. Thus, phosphate concentrate and phosphorus tailings with a grade of 35.71% and a recovery rate of 83.51% are obtained.

[0045] S4. The comprehensive tailings mixed with the magnetic product and the phosphorus tailings are used as building materials, filtered, and placed in an oven at 105°C for 24 hours to obtain unburned brick aggregate (since the phosphorus has been selected, the silicon content in the aggregate is significantly increased, meeting the requirements for preparing unburned bricks); the aggregate, cement and lime are evenly mixed according to a mass ratio of 82:10:8 (the optimal mass ratio obtained according to the cement ratio experiment and the lime ratio experiment), and the mixing water is added to the mixed dry material according to a water-to-material ratio of 12% (the mass ratio of water to dry material), and stirring is continued; then a polycarboxylate water reducer accounting for 0.5% of the cement dosage and triethanolamine accounting for 0.06% of the cement dosage are added, and stirring is continued; the mixture is then poured into a mold with a size of 200×100×60mm, and a press is used to apply a constant pressure of 10MPa to press and form it, and demolding obtains a brick embryo with a size of 200×100×50mm. Then the brick embryo was naturally cured in a curing box at a temperature of 18°C ​​and a humidity of 80%. After curing for 28 days, the tailings unfired brick was obtained. The physical properties of the brick at 28 days are shown in Table 3. All the properties meet the standard requirements of MU15 grade in "Non-fired garbage tailings bricks" (JC / T422-2007), and compared with ordinary fired bricks, they also show good physical properties.

[0046] Table 3 Comparison of physical properties of tailings unburned bricks

[0047] MU15 test items Standard value Tailings unburned bricks Sintered ordinary brick Compressive strength / MPa 15MPa 22.28MPa 20.21MPa Minimum compressive strength / MPa ≥12MPa 21.37MPa 19.37MPa Compressive strength after freezing / MPa ≥12MPa 17.76MPa 16.79MPa Loss of single brick in freeze-thaw cycle / (%) ≤2％ 0.95％ 1.20％ Drying shrinkage value / (%) ≤0.06％ 0.04％ 0.05％ Water absorption / (%) ≤18％ 3.2％ 5.1％ <![CDATA[Bulk density / (g / cm 3 )]]> — <![CDATA[2.17g / cm 3 ]]> <![CDATA[2.23g / cm 3 ]]> Softening performance ≥0.80 0.96 0.85

[0048] Example 2

[0049] Taking the ultra-poor vanadium-titanium magnetite tailings from a certain place as raw material, the properties and particle size composition of the tailings are shown in Tables 4 and 5.

[0050] Table 4 Main chemical composition of a super-poor vanadium-titanium magnetite tailings

[0051] chemical composition TFe mxD <![CDATA[P2O5]]> <![CDATA[TiO2]]> <![CDATA[Al2O3]]> <![CDATA[SiO2]]> <![CDATA[Na2O]]> <![CDATA[K2O]]> MgO CaO content / % 7.10 0.48 1.47 2.17 10.97 37.82 1.31 2.96 13.02 16.47

[0052] Table 5 Particle size distribution of tailings of a super-poor vanadium-titanium magnetite ore

[0053] Particle size / mm Weight / kg Yield / % Cumulative yield / % +3 0.06 1.09 1.09 -3+2 0.04 0.73 1.82 -2+1 0.14 2.55 4.37 -1+0.7 0.21 3.82 8.19 -0.7+0.5 0.68 12.39 20.58 -0.5+0.3 0.85 15.48 36.06 -0.3+0.2 0.60 10.93 46.99 -0.2+0.1 1.05 19.12 66.11 -0.1+0.074 0.27 4.93 71.04 -0.074 1.59 28.96 100.00

[0054] The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings has the following steps:

[0055] S1. The tailings in Table 4 and Table 5 are used as raw materials and ground in a ball mill. The grinding concentration is 45% and the grinding time is 8 min to obtain a grinding product with a -0.074 mm content of 80%.

[0056] S2. The grinding product with a grinding fineness of -0.074mm obtained in S1 is subjected to magnetic separation and tailings removal, and the magnetic field strength is 350kA / m to obtain magnetic products and non-magnetic products. The magnetic products are used as building materials, and the non-magnetic products are used as phosphorus flotation feed.

[0057] S3, the phosphorus flotation feed obtained in S2 is subjected to positive flotation of phosphorus. The flotation process includes one roughing, one sweeping and four refining processes. The phosphorus feed is first slurried, and the slurry concentration is 40%.

[0058] The reagent system for phosphorus roughing is: 2000g / t of sodium carbonate, stirring for 2 minutes, adding 600g / t of water glass, stirring for 2 minutes, adding 400g / t of FAB, stirring for 2 minutes, and scraping and foaming for 6 minutes.

[0059] The phosphorus sweeping agent system is: 200g / t FAB, stirring for 2min, scraping and foaming for 6min.

[0060] The reagent system for phosphorus concentration is as follows: 600g / t of water glass is added in the first, second and third concentration operations respectively, and the fourth concentration is a blank concentration. The stirring time is 2min, and the scraping time is 6min, 3min, 2.5min and 2.0min respectively. Thus, phosphate concentrate and phosphorus tailings with a grade of 35.18% and a recovery rate of 84.62% are obtained.

[0061] S4. The tailings mixed with the magnetic product and the phosphate tailings are used as building materials, filtered, and dried in an oven at 105°C for 24 hours to obtain aggregate for unburned bricks; the aggregate, cement and lime are uniformly mixed in a mass ratio of 85:10:5, and then the mixing water is added to the mixed dry materials in a water-to-material ratio of 15%, and the mixing water is continuously stirred; then 0.8% and 0.1% of the cement dosage of polycarboxylic acid water reducer and triethanolamine are added, and the stirring is continued; the raw materials are then poured into a mold with a size of 200×100×60mm. In the process, a press machine is used to apply a constant pressure of 15MPa to press and form, and demolding obtains a brick embryo with a size of 200×100×50mm; then the brick embryo is naturally cured in a curing box at a temperature of 22°C and a humidity of 90%, and after curing for 28 days, the tailings unfired brick is obtained; its physical properties at 28 days are shown in Table 6, and all properties meet the standard requirements of MU15 grade in "Non-fired garbage tailings bricks" (JC / T422-2007), and compared with sintered ordinary bricks, it also shows good physical properties.

[0062] Table 6 Physical properties of tailings unburned bricks

[0063] MU15 test items Standard value Tailings unburned bricks Sintered ordinary brick Compressive strength / MPa 15MPa 24.23MPa 21.21MPa Minimum compressive strength / MPa ≥12MPa 22.47MPa 20.67MPa Compressive strength after freezing / MPa ≥12MPa 18.23MPa 17.53MPa Loss of single brick in freeze-thaw cycle / (%) ≤2％ 0.86％ 1.60％ Drying shrinkage value / (%) ≤0.06％ 0.03％ 0.05％ Water absorption / (%) ≤18％ 2.7％ 6.4％ <![CDATA[Bulk density / (g / cm 3 )]]> — <![CDATA[1.98g / cm 3 ]]> <![CDATA[2.63g / cm 3 ]]> Softening performance ≥0.80 0.91 0.82

[0064] Finally, it should be noted that the above are only preferred embodiments of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings, characterized in that: The steps include: S1. Grinding the ultra-poor vanadium-titanium magnetite tailings; S2, the ground pulp is subjected to wet weak magnetic separation to pre-select tailings to obtain non-magnetic products and magnetic products. The magnetic products are used as unburned aggregates, and the non-magnetic products are subjected to flotation; S3, slurrying the non-magnetic product to obtain flotation pulp, and sequentially adding a regulator, a depressant, and a collector to the flotation pulp to perform positive flotation of phosphorus. The flotation process includes one roughing, one scavenging, and four cleaning processes to obtain phosphate concentrate and phosphate tailings; S4. The phosphate tailings and the magnetic product are mixed to obtain aggregates for unburned bricks, and the unburned bricks are obtained through drying, batching, molding and curing.

2. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: The grinding requirement in S1 is that the mineral with a particle size of -0.074 mm accounts for 60% to 90% of the mass fraction of the original ore.

3. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: S2 wet weak magnetic separation: 240~350kA / m.

4. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: The adjusting agent in S3 is sodium carbonate, and the dosage is 0-2000g / t.

5. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: The inhibitor in S3 is water glass, and the dosage is 0-1000g / t.

6. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: The collector in S3 is FAB, and the dosage is 100-400g / t.

7. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: During the roughing process, adjusters, inhibitors and collectors are added in sequence. Each agent is fully stirred after being added before the next agent is added. After the collector is added and stirred, the foam is scraped for 4 to 6 minutes to obtain a rough concentrate. The product in the tank is the scavenging feed. During the scavenging process, continue to add collectors in an amount of 100-300 g / t, fully stir, scrape and foam for 4-6 minutes to obtain phosphorus ore and phosphorus tailings; During the selection process, water glass is added at 0-600g / t in the first three levels of selection. No reagent is added in the fourth level of selection. Scraping and bubbling begins after sufficient stirring. The scraping and bubbling times for the four selections are 4-6min, 2-3min, 1.5-2.5min, and 1.0-2.0min respectively. Phosphate concentrate is obtained in the fourth selection, and the concentrate tailings from each level of selection are returned to the previous level of selection operation.

8. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: S4 in Drying: filter the mixture of magnetic product and phosphate tailings to remove moisture, and dry it in an oven at 105°C for 24 hours to obtain unburned brick aggregate; Ingredients: Mix unburned brick aggregate, cement, lime, triethanolamine and polycarboxylate water reducer in proportion, and stir the mixture repeatedly with a stirrer; Molding: Fill the mixed material into the mold and use the static pressure process of the press to form the brick embryo; Curing: After demoulding, the brick embryo is naturally cured in a curing box to obtain tailings unfired brick samples.

9. The comprehensive utilization method of ultra-poor vanadium-titanium magnetite tailings according to claim 1, characterized in that: The brick curing temperature is 20±2℃ and the humidity is 90%.

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