Flotation process for improving quality and reducing silicon of hematite

Abstract

The invention provides a flotation process for improving quality and reducing silicon of hematite. The flotation process is characterized by comprising the following steps: 1) putting the hematite into a thickener to adjust the concentration of ore pulp; 2) feeding into a first-stage stirring barrel, adding NaOH and an inhibitor, and stirring; 3) feeding into a secondary stirring barrel, adding CaO and a collecting agent, and stirring; 4) feeding to a roughing flotation machine for roughing to obtain primary concentrate and primary tailings; (5) a collecting agent is added into the primary concentrate for concentration, and secondary concentrate and secondary tailings are obtained; an inhibitor is added into the primary tailings, and the primary tailings are sent to a primary scavenging flotation machine for primary scavenging; (6) secondary concentrate is collected, the secondary tailings are returned to the roughing flotation machine in the step (4), the primary scavenging separation is returned to the thickener in the step (1), the primary scavenging separation tailings are subjected to secondary scavenging separation and tertiary scavenging separation, the tailings are collected, and the scavenging separation is returned to primary scavenging separation. The concentrate grade is 61% or above, the SiO2 content is 4.35%, the concentrate recovery rate is 84%, and the upgrading effect is remarkable.

Description

Technical Field

[0001] The invention relates to a mineral processing technology, in particular to a flotation process for improving the quality of hematite and reducing silicon, and belongs to the technical field of mineral processing. Background Art

[0002] The secondary concentrate produced by the iron ore concentrator is mostly hematite that can be recovered after the magnetite is recovered by weak magnetic method. The efficient recovery of this type of hematite is one of the keys to improving the comprehensive recovery rate of iron ore. The main component of hematite is ferric oxide. The mineral composition and distribution characteristics of hematite in different regions are quite different, and the separation process of different mines is quite different. For hematite with simple ore composition and coarse distribution, the staged grinding-gravity separation-magnetic separation-anion reverse flotation process can be used to obtain better separation indicators (such as Anshan Iron and Steel Group Gongchangling Mining Company, Qidashan, and Hujiamiao lean hematite), but most of the hematite with complex ore composition and fine distribution particle size is always difficult to effectively recover, such as oolitic hematite, Qidong hematite, etc.

[0003] The Dahongshan Iron Mine is mainly composed of magnetite and hematite. Magnetite is easy to beneficiate, while hematite is difficult to beneficiate due to its fine particle size. At present, it is mainly based on gravity separation and quality improvement, but the recovery rate is low, the concentrate grade is about 57%, and the SiO2 content is about 10%, which is not conducive to blast furnace smelting. At the same time, the separation process is long and produces a large amount of tailings. Therefore, it is necessary to improve the existing technology. Summary of the invention

[0004] The present invention aims to provide a flotation process for improving the quality and reducing silicon content of hematite, which has high concentrate recovery rate and grade, low concentrate SiO2 content, moderate separation process and low cost.

[0005] The present invention is accomplished by the following technical scheme: A flotation process for improving the quality of hematite and reducing silicon, characterized by comprising the following steps: 1) Put hematite into the thickener at a rate of 2-3t / h, and add water to the pulp concentration of 54-56% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 8-10 minutes to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing barrel, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 8-10 minutes, and the slurry concentration is adjusted to 40-42%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 40-43%, and sent to a roughing flotation machine at a rate of 2-3 t / h for roughing for 22-26 min to select primary concentrate and primary tailings; 5) Add a collector in an amount of 200 g / t to the primary concentrate selected in step 4), and add water to adjust the pulp concentration to 38-40%, and send it to a concentration flotation machine at a rate of 1-1.2 t / h for 23-24 min to select secondary concentrate and secondary tailings; add an inhibitor in an amount of 120 g / t to the primary tailings selected in step 4), and add water to adjust the pulp concentration to 37-39%, and send it to a primary scavenging flotation machine at a rate of 1-2 t / h for 25-26 min to select primary scavenged ore and primary scavenged tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7-8%, and return the secondary tailings to the roughing flotation machine in step 4) at a rate of 0.1t / h to participate in the roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 32-33%, and return the secondary tailings to the thickener in step 1) at a rate of 0.5-0.8t / h to participate in the adjustment of the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 41-42%, and send the secondary scavenged flotation machine at a rate of 1.0-1.3t / h for secondary scavenging for 20-21 minutes, and scavenging the secondary scavenged ore and secondary scavenged tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.7-0.9t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 38-39%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.1-0.3t / h for tertiary scavenging for 30-31 minutes, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore from step 7) to adjust the pulp concentration to 36-37%, and return the ore to the primary scavenging flotation machine in step 5) at a rate of 0.5-0.6t / h to participate in the first scavenging; collect the tertiary scavenging tailings from step 7) and send them to the tailings field for storage.

[0006] Furthermore, the inhibitor is a commercially available XGDF inhibitor, which is adsorbed on the surface of hematite to make the surface more hydrophilic, thereby inhibiting the flotation of hematite.

[0007] Furthermore, the collector is a commercially available XGDF inhibitor, which reacts with the surface of the gangue to make its surface hydrophobic and easily attached to bubbles to be floated out, thereby being separated from the hematite, while the hematite remains in the flotation machine. The anionic collector GH-HL is used after calcium ion activation, and the pH value of the slurry is adjusted by NaOH to improve the flotation effect.

[0008] The hematite described in the present invention is a secondary concentrate produced by the Dahongshan iron mine where the applicant is located. After weak magnetic recovery of magnetite, the hematite can be recycled. By flotation of the hematite to improve quality and reduce silicon, the comprehensive recovery rate of the iron ore is effectively improved, and the valuable resources in the iron ore are utilized as much as possible.

[0009] The present invention has the following advantages and effects. By adopting the above technical scheme, the grade of concentrate can be increased from 57% of the prior art to 61%, and the SiO2 content in the concentrate can be reduced from 10% of the prior art to 4.35%, and the concentrate recovery rate can be increased from 64% of the prior art to 84%, and its indicators are significantly improved. At the same time, the equipment is simple, the reagents are generally used, the mineral processing process is short, and the environment is not polluted. It is conducive to promoting the separation of difficult-to-separate hematite ore, expanding resource utilization, and fundamentally solving the problems of low recovery rate, low grade and high SiO2 content of fine-grained hematite ore that have long plagued mining companies. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is the process flow chart of this invention. DETAILED DESCRIPTION

[0011] The present invention will be further described below in conjunction with embodiments. Example 1

[0012] A flotation process for improving the quality of hematite and reducing silicon content, comprising the following steps: 1) Put 46.39% hematite into the thickener at a rate of 2t / h, and add water to the pulp concentration of 54% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 8 minutes to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing tank, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 8 minutes, and the slurry concentration is adjusted to 40%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 40%, and sent to a roughing flotation machine at a rate of 2 t / h for roughing for 22 minutes to select a primary concentrate and a primary tailings; 5) Add a collector in an amount of 200 g / t to the primary concentrate selected in step 4), and add water to adjust the pulp concentration to 38%, and send it to a concentration flotation machine at a rate of 1 t / h for 23 minutes to select secondary concentrate and secondary tailings; add an inhibitor in an amount of 120 g / t to the primary tailings selected in step 4), and add water to adjust the pulp concentration to 39%, and send it to a primary scavenging flotation machine at a rate of 1 t / h for a primary scavenging for 25 minutes to select primary scavenged ore and primary scavenging tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7%, and return it to the roughing flotation machine in step 4) at a rate of 0.1 t / h to participate in roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 32%, and return it to the thickener in step 1) at a rate of 0.5 t / h to participate in adjusting the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 41%, and send it to the secondary scavenging flotation machine at a rate of 1.0 t / h for secondary scavenging for 20 minutes, scavenging the secondary scavenged ore and secondary scavenging tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.7 t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 38%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.1 t / h for tertiary scavenging for 30 minutes, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore selected in step 7) to adjust the pulp concentration to 36%, and return the ore with an ore capacity of 0.5 t / h to the primary scavenging flotation machine in step 5) to participate in the first scavenging; collect the tertiary scavenging tailings selected in step 7) and send them to the tailings field for storage.

[0013] The secondary concentrate obtained in this Example 1 has the following indicators: concentrate yield 63.92%, TFe grade 60.86%, concentrate recovery rate 83.85%, and concentrate SiO2 content 4.35%. Example 2

[0014] A flotation process for improving the quality of hematite and reducing silicon content, characterized by comprising the following steps: 1) Put 3t / h of hematite with a grade of 46.22% into the thickener, and add water to the pulp concentration of 56% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 10 minutes to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing tank, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 10 min, and the slurry concentration is adjusted to 42%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 43%, and sent to a roughing flotation machine at a rate of 3 t / h for roughing for 26 minutes to select a primary concentrate and a primary tailings; 5) Add a collector in an amount of 200 g / t to the primary concentrate selected in step 4), add water to adjust the pulp concentration to 40%, and send it to a concentration flotation machine at a rate of 1.2 t / h for 24 min to select secondary concentrate and secondary tailings; add an inhibitor in an amount of 120 g / t to the primary tailings selected in step 4), add water to adjust the pulp concentration to 39%, and send it to a primary scavenging flotation machine at a rate of 2 t / h for a primary scavenging for 26 min to select primary scavenged ore and primary scavenging tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7-8%, and return the secondary tailings to the roughing flotation machine in step 4) at a rate of 0.1 t / h to participate in the roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 33%, and return the secondary tailings to the thickener in step 1) at a rate of 0.8 t / h to participate in the adjustment of the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 42%, and send the secondary scavenged tailings to the secondary scavenged flotation machine at a rate of 1.3 t / h for secondary scavenging for 21 minutes, and scavenging the secondary scavenged ore and secondary scavenged tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.9 t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 39%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.3 t / h for tertiary scavenging for 31 minutes, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore selected in step 7) to adjust the pulp concentration to 37%, and return the ore with an ore capacity of 0.6 t / h to the primary scavenging flotation machine in step 5) to participate in the first scavenging; collect the tertiary scavenging tailings selected in step 7) and send them to the tailings field for storage.

[0015] The secondary concentrate obtained in this Example 2 has the following indicators: concentrate yield 64.22%, TFe grade 60.91%, concentrate recovery rate 83.92%, and concentrate SiO2 content 4.26%. Example 3

[0016] A flotation process for improving the quality of hematite and reducing silicon content, characterized by comprising the following steps: 1) Put 46.39% hematite into the thickener at a rate of 2.5t / h, and add water to the pulp concentration of 55% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 9 minutes to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing tank, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 9 minutes, and the slurry concentration is adjusted to 41%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 41%, and sent to a roughing flotation machine at a rate of 2.5 t / h for roughing for 24 minutes to select a primary concentrate and a primary tailings; 5) Add a collector in an amount of 200 g / t to the primary concentrate selected in step 4), and add water to adjust the pulp concentration to 39%, and send it to a concentration flotation machine at a rate of 1.1 t / h for 24 minutes to select secondary concentrate and secondary tailings; add an inhibitor in an amount of 120 g / t to the primary tailings selected in step 4), and add water to adjust the pulp concentration to 38%, and send it to a primary scavenging flotation machine at a rate of 1 t / h for a primary scavenging for 25 minutes to select primary scavenged ore and primary scavenging tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7-8%, and return the secondary tailings to the roughing flotation machine in step 4) at a rate of 0.1 t / h to participate in the roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 32%, and return the secondary tailings to the thickener in step 1) at a rate of 0.6 t / h to participate in the adjustment of the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 41%, and send the secondary scavenged tailings to the secondary scavenged flotation machine at a rate of 1.2 t / h for secondary scavenging for 20 minutes, and scavenging the secondary scavenged ore and secondary scavenged tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.8 t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 38-39%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.2 t / h for tertiary scavenging for 30 minutes, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore selected in step 7) to adjust the pulp concentration to 36%, and return the ore with an ore capacity of 0.55 t / h to the primary scavenging flotation machine in step 5) to participate in the first scavenging; collect the tertiary scavenging tailings selected in step 7) and send them to the tailings field for storage.

[0017] The secondary concentrate obtained in this Example 3 has the following indicators: concentrate yield 63.96%, TFe grade 60.89%, concentrate recovery rate 83.95%, and concentrate SiO2 content 4.33%. Example 4

[0018] A flotation process for improving the quality of hematite and reducing silicon content, characterized by comprising the following steps: 1) Put 46.39% hematite into the thickener at a rate of 1.6t / h, and add water to the pulp concentration of 54.07% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 9.5 min to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing tank, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 9.5 min, and the slurry concentration is adjusted to 41.93%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 41.93%, and is sent to a roughing flotation machine at a rate of 2.32 t / h for roughing for 24.12 min to select a primary concentrate and a primary tailings; 5) In the primary concentrate selected in step 4), a collector is added in an amount of 200 g / t, and water is added to adjust the pulp concentration to 39.16%, and the concentrate is sent to a concentration flotation machine at a rate of 1.12 t / h for 23 min to select secondary concentrate and secondary tailings; in the primary tailings selected in step 4), an inhibitor is added in an amount of 120 g / t, and water is added to adjust the pulp concentration to 38.07%, and the concentrate is sent to a primary scavenging flotation machine at a rate of 1.76 t / h for 25.28 min to select primary scavenged ore and primary scavenged tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7.14%, and return the secondary tailings to the roughing flotation machine in step 4) at a rate of 0.1 t / h to participate in the roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 32.13%, and return the secondary tailings to the thickener in step 1) at a rate of 0.62 t / h to participate in the adjustment of the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 41.25%, and send the secondary scavenged tailings to the secondary scavenged flotation machine at a rate of 1.14 t / h for secondary scavenging for 20.66 min, and scavenging the secondary scavenged ore and secondary scavenged tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.8 t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 38.31%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.22 t / h for tertiary scavenging for 30.47 min, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore selected in step 7) to adjust the pulp concentration to 38.31%, and return the ore to the primary scavenging flotation machine in step 5) at a rate of 0.22 t / h to participate in the first scavenging; collect the tertiary scavenging tailings selected in step 7) and send them to the tailings field for storage.

[0019] The secondary concentrate obtained in this Example 4 has the following indicators: concentrate yield 63.71%, TFe grade 60.88%, concentrate recovery rate 84.01%, and concentrate SiO2 content 4.29%.

Claims

1. A flotation process for improving the quality of hematite and reducing silicon content, characterized in that The following steps are involved: 1) Put hematite into the thickener at a rate of 2-3t / h, and add water to the pulp concentration of 54-56% to obtain a primary mixed pulp; 2) The primary mixed slurry of step 1) is fed into a primary mixing tank, and NaOH is added at a rate of 1000 g / t, and an inhibitor is added at a rate of 700 g / t, and stirred for 8-10 minutes to obtain a secondary mixed slurry; 3) The secondary mixed slurry from step 2) is fed into a secondary mixing barrel, 500 g / t of CaO is added, and then 470 g / t of a collector is added, stirred for 8-10 minutes, and the slurry concentration is adjusted to 40-42%, thereby obtaining a tertiary mixed slurry; 4) The tertiary mixed slurry in step 3) is adjusted to a slurry concentration of 40-43%, and sent to a roughing flotation machine at a rate of 2-3 t / h for roughing for 22-26 min to select primary concentrate and primary tailings; 5) Add a collector in an amount of 200 g / t to the primary concentrate selected in step 4), and add water to adjust the pulp concentration to 38-40%, and send it to a concentration flotation machine at a rate of 1-1.2 t / h for 23-24 min to select secondary concentrate and secondary tailings; add an inhibitor in an amount of 120 g / t to the primary tailings selected in step 4), and add water to adjust the pulp concentration to 37-39%, and send it to a primary scavenging flotation machine at a rate of 1-2 t / h for 25-26 min to select primary scavenged ore and primary scavenged tailings; 6) Collect the secondary concentrate selected in step 5), adjust the concentration of the secondary tailings to 7-8%, and return the secondary tailings to the roughing flotation machine in step 4) at a rate of 0.1 t / h to participate in the roughing flotation; add water to the primary scavenged ore selected in step 5) to adjust the pulp concentration to 32-33%, and return the secondary tailings to the thickener in step 1) at a rate of 0.5-0.8 t / h to participate in the adjustment of the pulp concentration; add water to the primary scavenged tailings selected in step 5) to adjust the pulp concentration to 41-42%, and send the secondary scavenged flotation machine at a rate of 1.0-1.3 t / h for secondary scavenging for 20-21 min, and scavenging the secondary scavenged ore and secondary scavenged tailings; 7) The secondary scavenging ore from step 6) is returned to the primary scavenging flotation machine in step 5) at a rate of 0.7-0.9t / h to participate in the primary scavenging; water is added to the secondary scavenging tailings from step 6) to adjust the pulp concentration to 38-39%, and the tailings are sent to the tertiary scavenging flotation machine at a rate of 0.1-0.3t / h for tertiary scavenging for 30-31 minutes, and the tertiary scavenging ore and tertiary scavenging tailings are scavenged; 8) Add water to the tertiary scavenging ore from step 7) to adjust the pulp concentration to 36-37%, and return the ore to the primary scavenging flotation machine in step 5) at a rate of 0.5-0.6t / h to participate in the first scavenging; collect the tertiary scavenging tailings from step 7) and send them to the tailings field for storage.

2. The flotation process for improving the quality and reducing the silicon content of hematite according to claim 1, characterized in that The inhibitor is an XGDF inhibitor, which is adsorbed on the surface of hematite to make the surface more hydrophilic, thereby inhibiting the flotation of hematite.

3. The flotation process for improving the quality and reducing the silicon content of hematite according to claim 1, characterized in that The collector is an XGDF inhibitor, which reacts with the surface of the gangue to make it hydrophobic and easily attached to bubbles to be floated out, thereby separating from the hematite, while the hematite remains in the flotation machine. The anion collector GH-HL is used after calcium ion activation, and the pH value of the pulp is adjusted by NaOH to improve the flotation effect.

4. The flotation process for improving the quality and reducing the silicon content of hematite according to claim 1, characterized in that The hematite is a secondary concentrate produced by the Dahongshan Iron Mine, and can be recycled after weak magnetic recovery of magnetite.

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