A combined depressant suitable for the flotation separation of galena and chalcopyrite and method of use

Abstract

This invention discloses a combined inhibitor suitable for the flotation separation of galena and chalcopyrite, and its application method, belonging to the field of mineral processing technology. The combined inhibitor comprises 20%-50% iodine, 15%-30% tannic acid, and 30%-60% 1,3-bis(tris(hydroxymethyl)methylamino)propane. Compared with a single iodine inhibitor, the dosage of the combined inhibitor is reduced by 0.3-0.4 kg / t. The method described in this invention is simple, does not require pH adjustment, has no special temperature requirements, is non-toxic and environmentally friendly, and has strong applicability. The application of ultrasonic technology can significantly shorten the inhibition time and reduce the dosage of reagents, thereby improving the utilization rate of mineral resources and the overall efficiency of enterprises.

Description

Technical Field

[0001] This invention relates to a combined depressant suitable for the flotation separation of galena and chalcopyrite and its application method, belonging to the field of mineral flotation reagent technology. Background Technology

[0002] Copper and lead are essential non-ferrous metals vital to the national economy and people's livelihoods, widely used in defense technology, aerospace, automotive, construction, and electronics industries. In copper-lead polymetallic sulfide ores, chalcopyrite and galena are often densely coexisting with complex particle sizes. Due to their similar natural floatability, a mixed copper-lead flotation followed by separation process is commonly used. Therefore, the success of subsequent copper-lead separation is crucial to the processing of copper-lead polymetallic sulfide ores. Currently, copper-lead separation is mainly divided into lead-suppressing flotation of copper and copper-suppressing flotation of lead. The former uses chromates, potassium dichromate, and potassium permanganate as depressants, while the latter uses cyanide. Although these depressants have good selectivity, their use is restricted due to their high toxicity, and they typically require long oxidation times, generally over 30 minutes, and the slurry must be heated, resulting in extremely high processing costs. Meanwhile, with the growing awareness of sustainable development and environmental protection, people have placed higher demands on the efficient separation, comprehensive recovery, and clean production of mineral resources. Summary of the Invention

[0003] To address the shortcomings of current mineral processing technologies, the present invention aims to provide a combined depressant suitable for the flotation separation of galena and chalcopyrite, comprising 20%-50% iodine, 15%-30% tannic acid, and 30%-60% 1,3-bis(tris(hydroxymethyl)methylamino)propane.

[0004] Another object of the present invention is to provide a method of using the combined inhibitor, specifically including the following steps:

[0005] (1) Add the combined inhibitor to the copper-lead mixed concentrate and stir thoroughly. The dosage of the combined inhibitor in flotation is 0.5-2 kg / t.

[0006] (2) The slurry is subjected to enhanced oxidation by ultrasonic technology, and then filtered after 10-15 minutes of oxidation at room temperature.

[0007] (3) After filtration, water, collector and frother are added to the slurry for roughing to obtain copper rough concentrate and lead rough concentrate; after fine cleaning, copper concentrate and lead concentrate are obtained respectively.

[0008] (4) The collector and foaming agent used in this invention are conventional agents, generally aniline black powder, ethyl xanthate (collector), and pine oil foaming agent. The coarse selection and fine selection are conventional steps.

[0009] Preferably, in step (2) of the present invention, the frequency of the ultrasonic wave is 100-350 kHz and the field strength is 0.5-4 W / cm². 2 .

[0010] Preferably, in step (2) of the present invention, a peripheral radiation ultrasonic rod is used, and the installation ratio of the ultrasonic rod to the stirring tank is 15m. 2 Install 4-8 ultrasonic rods in the mixing tank.

[0011] The principle of this invention:

[0012] Iodine has a certain oxidizing property, mainly reacting with sulfur atoms on the surface of galena to oxidize them into sulfate ions. Tannic acid has a significant chelating effect on lead atoms on the galena surface, thus preventing the interaction between lead atoms and the collector xanthate. 1,3-bis(tris(hydroxymethyl)methylamino)propane can co-adsorb with tannic acid at lead atom sites on the galena surface, strengthening the chelation between lead atoms and tannic acid. Therefore, the combined use of these three agents can cause a strong simultaneous interaction between lead and sulfur atoms on the galena surface, resulting in a hydrophilic surface. The dosage of the combined depressant in flotation is 0.5-2 kg / t, which is 0.3-0.4 kg / t lower than that of a single iodine depressant.

[0013] The beneficial effects of this invention are:

[0014] The combined inhibitor used in this invention, compared with conventional oxidants, can achieve complete inhibition of galena within 4-10 minutes, resulting in a galena recovery rate of less than 10%. Furthermore, the combined inhibitor is composed of inorganic oxides and chelating organic compounds, exerting its inhibitory effect under both acidic and alkaline conditions. It exhibits strong adaptability to the pH of the slurry and has no special requirements regarding slurry pH. Residual reagents in the slurry can be reused without external discharge, posing no environmental hazard. In addition, to further enhance the inhibitory effect, ultrasound is used to strengthen the process, improving the mass transfer efficiency and collision probability between the mineral surface and the reagent, enhancing the interfacial turbulence effect, accelerating the reaction rate, further shortening the reaction time of the combined inhibitor by 30-50%, and reducing the reagent dosage by 20%. Therefore, ultrasound has a significant strengthening effect. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the process of this invention.

[0016] Figure 2 The graph shows the change in separation efficiency with oxidation time at different temperatures.

[0017] Figure 3 The graph shows the change in separation efficiency with and without ultrasound as a function of oxidation time. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0019] The specific method in this embodiment of the invention is as follows: For a mixed ore of galena and chalcopyrite, with 80% of the grinding fineness being -200 mesh, a xanthate collector is used to mix and float galena and chalcopyrite to obtain a mixed concentrate of galena and chalcopyrite. The mixed concentrate is concentrated to a pulp concentration of 50%, and a combination of inhibitors (iodine, tannic acid content, and 1,3-bis(tris(hydroxymethyl)methylamino)propane) is used at room temperature to inhibit galena. At the same time, ultrasonic treatment is added to enhance the inhibition effect and shorten the reaction time, completing the inhibition reaction within 5-10 minutes. After the reaction, ethyl xanthate and pine oil are added for flotation separation. Since galena is completely inhibited, it enters the tailings, while chalcopyrite does not react with the combination of inhibitors. Therefore, chalcopyrite has strong flotation potential and can still be floated by the xanthate collector, entering the concentrate, thereby efficiently separating galena and chalcopyrite.

[0020] Example 1

[0021] (1) Add the combined inhibitor to the copper-lead mixed concentrate and stir thoroughly. The amount of the combined inhibitor used in flotation is shown in Table 1. In this embodiment, inhibitors with different components and contents were added. The composition and amount of the combined inhibitor are shown in Table 1.

[0022] (2) Enhanced oxidation was carried out in the slurry using ultrasonic technology. After 13 minutes of oxidation at room temperature, the slurry was filtered. The frequency of the ultrasonic waves was 300 kHz and the field strength was 2 W / cm². 2 Peripheral radiation ultrasonic rods are used, with the installation ratio of ultrasonic rods to the mixing tank being 15m. 2 Six ultrasonic rods were installed in the mixing tank.

[0023] (3) After filtration, water, collector (butanol) and frother (oil No. 2) are added to the slurry for roughing to obtain copper rough concentrate and lead rough concentrate. The copper rough concentrate and lead rough concentrate are then finely treated to obtain copper concentrate and lead concentrate respectively.

[0024] Table 1

[0025]

[0026] The results of the flotation of the copper-lead mixed concentrate in this embodiment are shown in Table 2.

[0027] Table 2

[0028]

[0029] Table 2 shows that any inhibitor composed of three agents yields better experimental results than a combination inhibitor of two agents, and the results are also better than using a single agent. The higher the proportion of iodine in the combined inhibitor, the better the results, indicating that iodine has a strong inhibitory effect on galena and is a highly efficient inhibitor. Furthermore, the phenolic hydroxyl groups in tannic acid chemically adsorb onto the galena surface, creating a difference in adsorption density between galena and chalcopyrite. Additionally, the carboxyl groups in 1,3-bis(tris(hydroxymethyl)methylamino)propane also adsorb onto the galena surface. When tannic acid and 1,3-bis(tris(hydroxymethyl)methylamino)propane are used in combination, the increased number of functional groups significantly increases the hydrophobicity difference between galena and chalcopyrite. Finally, the combined inhibitor with iodine can inhibit galena from multiple aspects. The addition of ultrasound increases the slurry flow rate, allowing mineral particles in the slurry to react better with the agents, resulting in even better performance.

[0030] Example 2

[0031] Experimental Group 1: A 50% copper-lead mixed concentrate was used, with a combined inhibitor dosage of 1300 g / t (iodine 500 g / t, tannic acid 300 g / t, 1,3-bis(tris(hydroxymethyl)methylamino)propane 500 g / t). The temperature was controlled at room temperature, the ultrasonic frequency was 200 kHz, and the field strength was 2 W / cm². 2 The mixture is ultrasonically oxidized with an oxidant for 15 minutes, then No. 2 oil is added as a frother, and butyl xanthate is used as a collector to carry out a flotation process of roughing, scavenging and cleaning.

[0032] After flotation, the copper concentrate obtained in this embodiment has a copper grade of 19.61%, a lead grade of 2.99%, a copper recovery rate of 76.25%, and a lead recovery rate of 0.5%; and a lead concentrate has a copper grade of 0.34%, a lead grade of 70.12%, a copper recovery rate of 10.96%, and a lead recovery rate of 94.04%.

[0033] Control group 1: No ultrasound treatment

[0034] Using a 50% copper-lead mixed concentrate, with a combined depressant dosage of 1300 g / t (500 g / t iodine, 300 g / t tannic acid, and 500 g / t 1,3-bis(tris(hydroxymethyl)methylamino)propane), oxidation was carried out at 70℃ for 60 minutes using the combined depressant. Then, No. 2 oil was added as a frother, and butyl xanthate was used as a collector for a flotation process consisting of one roughing, one scavenging, and two cleaning operations. The resulting concentrates were: copper grade 16.33%, lead grade 4.46%, copper recovery 62.38%, and lead recovery 0.65%; and lead concentrate 0.37%, lead grade 67.48%, copper recovery 12.61%, and lead recovery 91.67%.

[0035] As can be seen from the above experiments, the combination inhibitor of the present invention, combined with ultrasound, can still achieve good separation effect in a short time at room temperature.

[0036] Example 3

[0037] In this embodiment, a mixed ore of 200g galena and 100g chalcopyrite was used to conduct a comparative test on the separation effect. Reagents were added to the mixed concentrate slurry, and then the same flotation operation was performed to obtain the copper and lead separation efficiency data when a test condition was changed. The process flow of concentrate flotation under experimental conditions is existing technology and is well known to those skilled in the art. The specific operation steps will not be described in detail here.

[0038] Experimental Group 1: Added combination inhibitors and ultrasound (ultrasound frequency 200kHz, field strength 2W / cm²). 2 It only takes 10 minutes to achieve a separation efficiency of 90%, generating a strong synergistic effect and greatly improving the oxidation capacity of the combined inhibitors for galena.

[0039] Control group 1: Added conventional reagent: potassium dichromate, and subjected to four temperature conditions (25℃, 40℃, 60℃, and 80℃). The separation efficiency increased with time as follows: Figure 2 As shown; by Figure 2 It can be seen that at 40℃, the separation efficiency reaches 40% after 50 minutes, and the separation of lead and copper is difficult. As the ambient temperature increases, the separation efficiency of lead and copper increases, but at 60℃ and 80℃, it still takes 50 minutes to reach a separation efficiency of 60-80%.

[0040] Control Group 2: Added combination inhibitor: Under normal temperature (25℃) conditions, using the combination inhibitor (iodine 500g / t, tannic acid 300g / t, 1,3-bis(tris(hydroxymethyl)methylamino)propane 500g / t), the separation efficiency reached 38% after 15 minutes; while using potassium dichromate at 25℃, the separation efficiency was only about 20% after 50 minutes; indicating that the combination inhibitor has extremely strong oxidizing power.

[0041] As can be seen from the above examples, the combined inhibitors have a significant separation effect at room temperature and within a short period of time.

Claims

1. A combined depressant suitable for the flotation separation of galena and chalcopyrite, characterized in that: The composition comprises 20-50% of iodine, 15-30% of tannic acid and 30-60% of 1,3-bis(tris(hydroxymethyl)methylamino)propane.

2. The method of using a combination inhibitor of claim 1, wherein, Specifically comprising the following steps: (1) adding a combined inhibitor to the copper-lead mixed concentrate and stirring thoroughly, wherein the combined inhibitor is used in an amount of 0.5-2 kg / t in the flotation; (2) strengthening oxidation in the slurry through ultrasonic technology, and filtering after oxidation at normal temperature for 10-15 minutes; (3) adding water, a collector and a frother to the filtered slurry for roughing to obtain a copper rough concentrate and a lead rough concentrate; and the copper rough concentrate and the lead rough concentrate are respectively subjected to cleaning to obtain a copper concentrate and a lead concentrate.

3. The method of using a combination inhibitor of claim 1, wherein: The frequency of the ultrasonic wave in step (2) is 100-350 kHz, and the field strength is 0.5-4 W / cm 2 , covering 1 / 3-1 / 2 of the space in the treatment tank.

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