Smelting solid waste purifying agent and application thereof

Abstract

The invention discloses a smelting solid waste purifying agent and application thereof, and aims to provide a purifying agent which is good in smelting solid waste treatment effect, high in iron extraction rate and low in coal consumption and application thereof. The smelting solid waste purifying agent provided by the invention is mainly prepared by mixing calcium fluoride and calcium oxide according to the mass ratio of (0.2-0.3): (0.7-0.8). The application method provided by the invention comprises the following steps: adding the smelting solid waste purifying agent and coal into the smelting solid waste, uniformly mixing, heating to 1100-1400 DEG C, keeping the temperature for 2-4 hours, and extracting iron in the smelting solid waste by adopting a magnetic separation mode; the smelting solid waste purifying agent accounts for 7-12% of the smelting solid waste by mass, and the coal accounts for 14% of the smelting solid waste by mass. The method has the advantages of high grade of extracted iron, low raw coal consumption and the like, and can be widely applied to treatment of copper ore smelting waste residues, tin ore smelting waste residues or red mud.

Description

TECHNICAL FIELD

[0001] The present application relates to a solid waste purification agent, in particular to a smelting solid waste purification agent and its application, and belongs to the technical field of smelting solid waste treatment. BACKGROUND

[0002] Tailings are solid waste generated in the ore dressing process of mines, and long-term stacking not only occupies land resources, but also easily causes heavy metal leaching pollution and soil erosion. Smelting solid waste contains a large amount of valuable metals, especially iron and zinc, among which the iron content can reach 10-43%, and the residual zinc content is between 0.5-5%, which has significant resource potential.

[0003] Iron in smelting solid waste often exists in the form of hematite and limonite, and zinc is often contained in sphalerite or heteropolar ore, which is difficult to realize efficient separation by gravity separation, magnetic separation or flotation due to fine mineral particle size and close symbiosis. Although direct reduction smelting can recover metals, high silicon and aluminum content in tailings can easily form slag, increase energy consumption and metal loss; the volatilization characteristics of zinc can also cause dust pollution. Although acid leaching (such as sulfuric acid) can dissolve iron and zinc, impurities such as calcium and magnesium are also dissolved synchronously, which increases the burden of subsequent purification; the selectivity of alkali leaching (such as ammonia) to zinc is good, but it is ineffective for iron, and the cost of reagent is high. Traditional leaching agents cannot realize efficient step-by-step extraction of iron and zinc, and are easy to produce iron hydroxide gel or iron pyrite slag, which affects the recovery rate of zinc.

[0004] In addition, the existing technologies for recovering and purifying metallic iron from smelting solid waste mainly include: 1. Flotation-magnetic separation combined process, mainly suitable for tailings with zinc sulfide as the main component, which can realize iron grade of 61% and low recovery rate (only 5%). 2. Pyrometallurgical technology, suitable for copper smelting tailings with high iron content (~ 42%) and medium zinc content (~ 3%), iron directly forms iron blocks, which is limited by high energy consumption and complex flue gas treatment, and the iron powder grade is 55-65%. 3. New chemical recovery method, which is limited by high cost and low process value. SUMMARY

[0005] In view of the above defects in the prior art, the present application aims to provide a smelting solid waste purification agent and its application, which has good tailings treatment effect, high iron extraction rate and low coal consumption.

[0006] In order to achieve the above purpose, the smelting solid waste purification agent provided by the present application is mainly composed of calcium fluoride and calcium oxide mixed at a mass ratio of (0.2-0.3):(0.7-0.8), the purity of the calcium fluoride is ≥80%, and the purity of the calcium oxide is ≥85%.

[0007] Preferably, the mass ratio of calcium fluoride to calcium oxide is 1:3.

[0008] Further, further comprising sodium carbonate, calcium fluoride, calcium oxide, the mass ratio of sodium carbonate is (0.1-0.2):(0.4-0.55):(0.4-0.55), the purity of sodium carbonate is greater than or equal to 90%.

[0009] Further, the mass ratio of calcium fluoride, calcium oxide and sodium carbonate is 0.16:0.41:0.41.

[0010] Further, further comprising manganese dioxide, anhydrous borax and mill scale, the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is (0.1-0.15):(0.25-0.4):(0.25-0.4):(0.05-0.1):(0.05-0.1):(0.01-0.1), the purity of manganese dioxide is greater than or equal to 99%, the purity of anhydrous borax is greater than or equal to 70%, and the purity of mill scale is greater than or equal to 95%.

[0011] Further, the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.14:0.365:0.365:0.073:0.036:0.018.

[0012] The application method of the smelting solid waste purifying agent provided by the application is as follows: the smelting solid waste purifying agent and coal are added into smelting solid waste, uniformly mixed, heated to 1100-1400 DEG C, and kept for 2-4 hours, and then the iron in the smelting solid waste is extracted by magnetic separation after cooling; the mass ratio of the smelting solid waste purifying agent to the smelting solid waste is 7-12%, the mass ratio of the coal to the smelting solid waste is 14%, and the carbon content of the coal is greater than or equal to 85%; the smelting solid waste is one of copper smelting slag, tin smelting slag and red mud.

[0013] The preferred scheme of the application method of the smelting solid waste purifying agent provided by the application is that the heating temperature is 1250 DEG C, the keeping time is 4 hours, and the mass ratio of the smelting solid waste purifying agent to the smelting solid waste is 12%.

[0014] In the above technical scheme, calcium fluoride and calcium oxide mainly play a role in removing silicon, aluminum and other impurities in the tailings, and the reaction principle is CaF2+SiO2=CaSiO3+2HF, CaO+SiO2=CaSiO3 and CaO+AlO3=Ca3(AliO)2; sodium carbonate and calcium oxide have a synergistic effect, react with generated silicates to generate low-melting substances, and the principle is NaCO3+CaSiO3=NaSiO3+CaCO3; the role of manganese dioxide is to assist melting, mill scale has reducing property, and borax has the effect of airway aggregation.

[0015] Compared with the prior art, the smelting solid waste purifying agent provided by the present application is used to treat smelting solid waste (copper mine smelting slag, tin mine smelting slag and tailings such as red mud) through a high-temperature smelting, ball milling and magnetic separation composite process, so that the qualified rate of the extracted iron powder is greater than or equal to 98%, the grade is 80-93%, the problem of low iron grade is better solved, and the consumption of raw coal is low (the single consumption of coal powder is 0.14 tons / ton, which is lower than the average single consumption of coal powder in the industry, i.e. 0.35 tons / ton). DETAILED DESCRIPTION

[0016] The present application will be further described below in combination with copper mine smelting slag, tin mine smelting slag, red mud and specific examples: I. Taking copper mine smelting slag as the treatment object Example

[0017] 1) The calcium fluoride and the calcium oxide are mixed at a mass ratio of 0.25:0.75, stirred at 100 rpm for 30 min to obtain a smelting solid waste purifying agent; 2) The smelting solid waste purifying agent is mixed with the copper mine smelting slag, stirred for 5 min, and then mixed uniformly after the addition of coal, to obtain pretreated copper mine smelting slag; the mass ratio of the smelting solid waste purifying agent to the copper mine smelting slag is 12%, and the mass ratio of the coal to the copper mine smelting slag is 14%; 3) The pretreated copper mine smelting slag is sent into a reduction furnace for heat treatment at 1250℃ for 4 h to obtain a bulk silicon-iron mixture; 4) The bulk silicon-iron mixture is ball milled for 30 min, and the powder is subjected to magnetic separation to obtain an 83% high-grade iron powder mixture.

[0018] Example 2, each step is the same as that in Example 1. The mass ratio of the calcium fluoride to the calcium oxide is 0.2:0.8, and the grade of the obtained iron powder mixture is 77%.

[0019] Example 3, each step is the same as that in Example 1. The mass ratio of the calcium fluoride to the calcium oxide is 0.3:0.7, and the grade of the obtained iron powder mixture is 82%.

[0020] Example 4, each step is the same as that in Example 1. The smelting solid waste purifying agent is mixed by mixing calcium fluoride, calcium oxide and sodium carbonate at a mass ratio of 0.16:0.41:0.41, and the grade of the obtained iron powder mixture is 91%.

[0021] Example 5, each step is the same as that in Example 4. The mass ratio of the calcium fluoride, the calcium oxide and the sodium carbonate is 0.1:0.45:0.45, and the grade of the obtained iron powder mixture is 79%.

[0022] Example 6, each step is the same as example 4. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate is 0.1:0.55:0.4, mixed into the proportion, the grade of the iron powder mixture is 86%.

[0023] Example 7, each step is the same as example 4. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate is 0.1:0.4:0.55, mixed into the proportion, the grade of the iron powder mixture is 83%.

[0024] Example 8, each step is the same as example 4. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate is 0.2:0.4:0.4, mixed into the proportion, the grade of the iron powder mixture is 77%.

[0025] Example 9, each step is the same as example 4. Wherein the mass ratio of smelting solid waste pure agent to copper smelting slag is 10%, the grade of the iron powder mixture is 88%.

[0026] Example 10, each step is the same as example 4. Wherein the mass ratio of smelting solid waste pure agent to copper smelting slag is 8%, the grade of the iron powder mixture is 85%.

[0027] Example 11, each step is the same as example 4. Wherein the heat treatment temperature is 1100℃, the grade of the iron powder mixture is 87%.

[0028] Example 12, each step is the same as example 4. Wherein the heat treatment temperature is 1400℃, the grade of the iron powder mixture is 86%. Example

[0029] 1) calcium fluoride, calcium oxide mixed, 100 rpm stirring, adding sodium carbonate, manganese dioxide mixed, finally adding anhydrous borax, iron oxide scale stirring 30 min, get smelting solid waste purification agent; the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and iron oxide scale is 0.14:0.365:0.365:0.073:0.036:0.018; 2) the smelting solid waste purification agent is mixed with copper smelting slag, stirring 5 min, adding coal after mixing evenly, get pretreated copper smelting slag; ensure the mass ratio of smelting solid waste pure agent to copper smelting slag is 7%, the mass ratio of coal to copper smelting slag is 14%; 3) the pretreated copper smelting slag is sent into the reduction furnace, 1200℃ heat treatment 4h, get block silicon iron mixture; 4) the block silicon iron mixture is ball milled for 30 min, the powder is magnetically selected, get 90% high grade iron powder mixture.

[0030] Example 14, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.1:0.39:0.4:0.05:0.05:0.01, the grade of the obtained iron powder mixture is 87%.

[0031] Example 15, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.1:0.4:0.39:0.05:0.05:0.01, the grade of the obtained iron powder mixture is 85%.

[0032] Example 16, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.1:0.3:0.4:0.05:0.05:0.1, the grade of the obtained iron powder mixture is 86%.

[0033] Example 17, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.1:0.4:0.3:0.05:0.05:0.1, the grade of the obtained iron powder mixture is 83%.

[0034] Example 18, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.1:0.35:0.35:0.05:0.05:0.1, the grade of the obtained iron powder mixture is 87%.

[0035] Example 19, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.15:0.25:0.4:0.05:0.05:0.1, the grade of the obtained iron powder mixture is 82%.

[0036] Example 20, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.15:0.4:0.25:0.05:0.05:0.1, the grade of the obtained iron powder mixture is 87%.

[0037] Example 21, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and mill scale is 0.15:0.3:0.25:0.1:0.1:0.1, the grade of the obtained iron powder mixture is 81%.

[0038] Example 22, each step is the same as example 13. Wherein the mass ratio of calcium fluoride, calcium oxide, sodium carbonate, manganese dioxide, anhydrous borax and iron scale is 0.15:0.25:0.3:0.1:0.1:0.1, the grade of the obtained iron powder mixture is 80%.

[0039] II. Tin ore smelting slag as the processing object Example 23, each step is the same as example 1. Wherein the copper ore smelting slag is replaced by tin ore smelting slag, and the grade of the obtained iron powder mixture is 80%.

[0040] Example 24, each step is the same as example 4. Wherein the copper ore smelting slag is replaced by tin ore smelting slag, and the grade of the obtained iron powder mixture is 90%.

[0041] Example 25, each step is the same as example 13. Wherein the copper ore smelting slag is replaced by tin ore smelting slag, and the grade of the obtained iron powder mixture is 91%.

[0042] III. Red mud as the processing object Example 26, each step is the same as example 1. Wherein the copper ore smelting slag is replaced by red mud, and the grade of the obtained iron powder mixture is 92%.

[0043] Example 27, each step is the same as example 4. Wherein the copper ore smelting slag is replaced by red mud, and the grade of the obtained iron powder mixture is 92%.

[0044] Example 28, each step is the same as example 13. Wherein the copper ore smelting slag is replaced by red mud, and the grade of the obtained iron powder mixture is 93%.

[0045] In each of the above examples, the purity of calcium fluoride is ≥80%, the purity of calcium oxide is ≥85%, the purity of sodium carbonate is ≥90%, the purity of manganese dioxide is ≥99%, the purity of anhydrous borax is ≥70%, the purity of iron scale is ≥95%, and the carbon content of coal is ≥85%.

Claims

1. A smelting solid waste purifying agent characterized by: The calcium fluoride and the calcium oxide are mixed according to the mass ratio of (0.2-0.3):(0.7-0.8), the purity of the calcium fluoride is greater than or equal to 80%, and the purity of the calcium oxide is greater than or equal to 85%.

2. The smelting solid waste purifying agent according to claim 1, characterized by: The mass ratio of the calcium fluoride to the calcium oxide is 1:

3.

3. The smelting solid waste purifying agent according to claim 1, characterized by: The mass ratio of the calcium fluoride, the calcium oxide and the sodium carbonate is (0.1-0.2):(0.4-0.55):(0.4-0.55), the purity of the sodium carbonate is greater than or equal to 90%.

4. The smelting solid waste purifying agent according to claim 3, characterized by: The mass ratio of the calcium fluoride, the calcium oxide and the sodium carbonate is 0.16:0.41:0.

41.

5. The smelting solid waste purifying agent according to claim 1, characterized by: The mass ratio of the calcium fluoride, the calcium oxide, the sodium carbonate, the manganese dioxide, the anhydrous borax and the iron oxide scale is (0.1-0.15):(0.25-0.4):(0.25-0.4):(0.05-0.1):(0.05-0.1):(0.05-0.1), the purity of the manganese dioxide is greater than or equal to 99%, the purity of the anhydrous borax is greater than or equal to 70%, and the purity of the iron oxide scale is greater than or equal to 95%.

6. The smelting solid waste purifying agent according to claim 5, characterized by: The mass ratio of the calcium fluoride, the calcium oxide, the sodium carbonate, the manganese dioxide, the anhydrous borax and the iron oxide scale is 0.14:0.365:0.365:0.073:0.036:0.

018.

7. Use of a smelting solid waste purifying agent according to any one of claims 1 to 6, characterized in that: The smelting solid waste is mixed with the smelting solid waste purifying agent and coal, and then heated to 1100-1400 DEG C for 2-4 hours, and then cooled and extracted by magnetic separation to obtain iron from the smelting solid waste, the mass ratio of the smelting solid waste purifying agent to the smelting solid waste is 7-12%, the mass ratio of the coal to the smelting solid waste is 14%, the carbon content of the coal is greater than or equal to 85%, and the smelting solid waste is one of copper smelting slag, tin smelting slag and red mud.

8. The use of a smelting solid waste purifying agent according to claim 7, characterized in that: The heating temperature is 1250 DEG C, the holding time is 4 hours, and the mass ratio of the smelting solid waste purifying agent to the smelting solid waste is 12%.