Preparation of inhibitor DYL and method for removing silicon and calcium from magnesite through direct flotation by using inhibitor DYL

Abstract

The invention provides preparation of an inhibitor DYL and a method for removing silicon and calcium from magnesite through direct flotation of the inhibitor DYL, and belongs to the technical field of direct flotation separation and purification of magnesite. The invention provides a novel inhibitor for direct flotation of magnesite and synchronous desiliconization and calcium removal and an application method of the novel inhibitor in direct flotation of magnesite, and the inhibitor DYL is prepared by compounding HCA (hydroxycitric acid) and curdlan according to the mass ratio of 1: 1. The compound is used as an inhibitor for flotation separation of magnesite, dolomite and talc; the inhibitor DYL can remove calcium-containing ore and silicon-containing ore at the same time, the operation steps in actual production are simplified, the production investment is reduced, the inhibitor for inhibiting silicon and calcium is combined in one step to be added, and the ore dressing efficiency can be greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of positive flotation separation and purification of magnesite, and particularly relates to a method for preparing a depressant DYL and using the desiliconization and calcium removal method of magnesite in positive flotation. Background Art

[0002] Magnesium is one of the light metals with the largest total resources on earth, with a density of 1.74g / cm 3 , with certain ductility and heat dissipation. Its superior damping performance, high specific strength and easy recycling and reuse make magnesium, magnesium alloys and magnesium products widely used in refractory materials, medical, military, aviation, automobiles and instruments.

[0003] One of the main sources of the magnesium industry chain is magnesite. Magnesite is a dominant mineral resource in my country, of which 80% to 90% is used to manufacture refractory materials and has a high development and utilization value. At present, the magnesite sold by Chinese companies is mainly low- and medium-grade products. The research and development technology for high-purity high-end products is not mature enough, resulting in the continuous mining of rich mines in recent years, the abandonment of low-grade magnesite, and the exhaustion of high-quality magnesite. The mining and utilization of low-grade magnesite resources has become the most important development trend at present. To this end, improving mineral processing technology and turning low-grade magnesite into treasure are of great significance to solving the shortage of high-grade magnesite resources and promoting the sustainable development of magnesite resources.

[0004] Most domestic ore dressing plants use flotation to select magnesite. The main task of magnesite purification is to "remove silicon and reduce calcium", that is, to remove calcium carbonate minerals and silicate minerals in the ore. Calcium carbonate gangue minerals include dolomite, calcite, etc. These calcium impurities will form calcium silicate substances after calcination, which will easily break the refractory materials when cooled; silicate minerals include quartz, talc, serpentine, etc. In the subsequent processing and calcination process, these minerals will form fusible silicate substances, which will reduce the strength of the refractory materials. Therefore, calcium gangue and silicon gangue largely determine the sorting quality of magnesite. The mass fraction of CaO and SiO2 required for the third-grade magnesite is less than 1.5%, while the mass fraction of CaO and SiO2 required for the special-grade magnesite is less than 0.6%. In actual production, amine collectors are generally used for reverse flotation to remove part of the silicon-containing gangue, reducing the pressure of subsequent direct flotation magnesite quality improvement. In the direct flotation, inhibitors that inhibit silicon and calcium are used to further purify the magnesite, thereby obtaining better separation effects.

[0005] As magnesite ore becomes poorer and finer, the difficulty of ore separation is further increased. Therefore, it is very important to develop a new and efficient flotation agent for use in magnesite beneficiation. The inhibitor (DYL for short) of the present invention not only has a good inhibitory effect on calcium-containing and silicon-containing gangue minerals, but also has profound reference value in simplifying the flotation process, reducing production costs, solving the shortage of high-grade magnesite resources, and promoting the sustainable development of magnesite resources in production operations. Summary of the invention

[0006] The object of the present invention is to provide a novel inhibitor for simultaneous desiliconization and calcium removal in magnesite direct flotation and an application method thereof in magnesite direct flotation. The inhibitor DYL is prepared by compounding HCA (hydroxycitric acid) and curdlan in a mass ratio of 1:1. In the direct flotation process, calcium-containing gangue minerals and silicon-containing gangue minerals can be effectively inhibited simultaneously, and the concentrate can be ensured to have a high purity and recovery rate.

[0007] The invention provides a method for using an inhibitor DYL for simultaneous desiliconization and calcium removal in positive flotation of magnesite, which is to use the inhibitor as an inhibitor for flotation separation of magnesite from dolomite and talc in the process of positive flotation and desiliconization and calcium removal of magnesite.

[0008] A method for preparing an inhibitor DYL comprises the following steps:

[0009] The HCA solid powder is dissolved in deionized water, and after constant volume, a dilute HCA solution with a mass concentration of 0.5% to 5% is prepared; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, a dilute curdlan solution with a mass concentration of 0.5% to 5% is prepared; finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed at a mass ratio of 1:1 to obtain the inhibitor DYL.

[0010] Furthermore, the amount of sodium hydroxide added is 10% to 30% of the mass of the curdlan solid powder, and the temperature of the constant temperature water bath is maintained between 50°C and 90°C.

[0011] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0012] S1: Take pure magnesite in the particle size range of -74+38μm, add deionized water to dissolve it, make a pulp for flotation test, and put it into the flotation tank;

[0013] S2: Place the flotation cell containing the slurry on the flotation machine for stirring to make the pure mineral particles evenly distributed in the slurry;

[0014] S3: Use HCl solution or NaOH solution to adjust the slurry to a set pH value, and stir it for 1 to 3 minutes under this pH condition;

[0015] S4: Add the inhibitor DYL to allow the agent to fully react with the mineral surface for 1 to 3 minutes;

[0016] S5: adding a collector to allow the agent to fully react with the mineral surface for 1 to 3 minutes, and keeping the pH value constant during the addition of the agent. The collector is one or two of sodium oleate, oxidized paraffin soap, sodium petroleum sulfonate, and benzohydroxamic acid;

[0017] S6: After the agent has fully acted, manually scrape the foam for 3 to 5 minutes, put the obtained foam product and the product at the bottom of the tank into an oven for drying, weighing, calculating the recovery rate, and testing the MgO, CaO, and SiO2 contents.

[0018] In step S1, the MgO content of pure magnesite is 43.1% to 47.8% by weight, the CaO content is 0.1% to 0.6%, the SiO2 content is 0.01% to 0.2%, the Al2O3 content is 0.1% to 0.3%, and the TFe content is 0.1%; the SiO2 content of pure talc is 61.78% to 63.37% by weight, the MgO content is 31.01% to 31.88%, the Al2O3 content is 0.1% to 0.2%, and the TFe content is 0.1%.

[0019] In the step S1, the pure magnesite mineral is selected from one or more of the pure magnesite minerals of magnesite, dolomite and talc. When multiple minerals are added, the added mass ratio is magnesite: dolomite: talc = (1-16): 1:1.

[0020] In the step S1, the concentration of the slurry is 0.050-0.080 g / mL.

[0021] In step S2, the stirring speed of the flotation machine is 1900-2100 r / min; and the stirring time is 1-3 min.

[0022] In step S3, the mass concentration of the HCl solution is 0.1% to 5%, and the mass concentration of the NaOH solution is 0.1% to 5%; and the pH value range is 7 to 12.

[0023] In step S4, the dosage of the inhibitor DYL is 100-350 mg / L.

[0024] In step S5, the dosage of sodium oleate is 33-150 mg / L, the dosage of oxidized paraffin soap is 120-150 mg / L, the dosage of sodium petroleum sulfonate is 210-360 mg / L, and the dosage of benzohydroxamic acid is 100-150 mg / L.

[0025] In the single mineral test obtained by this method, the yield of magnesite is 71.0% to 98.4%, and the yield of talc is 0.3% to 94.4%;

[0026] In the test of mixed minerals obtained by this method, the concentrate yield was 62.91% to 86.79%, the MgO content was 46.9% to 47.8%, the SiO2 content was 0.1% to 0.2%, the CaO content was 0.1% to 0.2%, and the MgO recovery rate was 88.9% to 93.2%.

[0027] The inhibitor of the present invention is a compound of HCA and curdlan, which can exert the synergistic effect of the two. Both calcium-containing and silicon-containing gangue minerals can be well inhibited, and the floatability of magnesite is less affected. Therefore, applying DYL to positive flotation can improve the mineral processing efficiency and realize the one-step removal of CaO and SiO2.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1) The inhibitor DYL selected in the present invention has a relatively high selective inhibitory effect on both silicon-containing and calcium-containing gangue minerals in positive flotation, and has a small effect on the floatability of magnesite, thereby ensuring a high recovery rate of magnesite. This agent has an important reference value for the efficient separation of magnesite ore;

[0030] 2) The inhibitor DYL selected in the present invention can simultaneously suppress the floating of calcium-containing and silicon-containing gangue minerals in positive flotation. Compared with HCA, HCA can only remove calcium-containing gangue, and silicon-containing gangue needs to be removed by adding another agent, but DYL can simultaneously remove calcium-containing and silicon-containing ores, which simplifies the operation steps in actual production and reduces production investment. The inhibitors that suppress silicon and calcium are combined in one step for addition, which can greatly improve the ore dressing efficiency;

[0031] 3) The inhibitor DYL selected in the present invention is a new agent compounded from two agents HCA and curdlan. Both HCA and curdlan are used in the food industry and are environmentally friendly and pollution-free. Therefore, the agent DYL has no harm to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flow chart of a method for using a DYL inhibitor in the positive flotation of magnesite for simultaneous desiliconization and calcium removal;

[0033] Figure 2 1 is a graph showing the relationship between pH value and recovery rate in Example 1 of the present invention;

[0034] Figure 3 This is a graph showing the relationship between the dosage of the inhibitor DYL and the recovery rate in Example 2 of the present invention. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with the examples, but the examples are not intended to limit the technical solutions of the present invention. The test methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials are commercially available unless otherwise specified.

[0036] In order to better explain the present invention, the main contents of the present invention are further explained below in conjunction with specific laboratory examples, but the contents of the present invention are not limited to the following examples.

[0037] Example 1

[0038] A method for preparing an inhibitor DYL comprises the following steps:

[0039] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 0.5%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 0.5%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 1%.

[0040] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0041] Weigh 2.0g of magnesite, dolomite and talc with a particle size range of -74+38μm for flotation respectively, add 30ml of deionized water to dissolve, put into a 50ml flotation tank for stirring, so that the mineral particles are evenly dispersed in the slurry.

[0042] Adjust the pH value of the slurry to 7, 8, 9, 10, 11, and 12, respectively, stir for 2 minutes, and Figure 1 The dosing sequence is shown in the figure. 100 mg / L of inhibitor DYL and 100 mg / L of collector sodium oleate are added to the slurry in turn. The stirring time is 3 minutes. The pH value of the slurry is kept constant during the dosing. After the agent is fully effective, the foam is scraped manually for 3 minutes. The obtained foam product and the bottom product of the tank are put into the oven for drying, weighed, and the recovery rate is calculated. The results are shown in Table 1. Figure 2 shown.

[0043] Table 1 Relationship between pH and recovery of magnesite, dolomite and talc (%)

[0044] 7 8 9 10 11 12 Magnesite 88.67 86.66 76.92 95.6 96.58 98.12 dolomite 81.1 86.32 29.7 62.84 83.45 83.62 talc 3.67 1.94 2.24 1.83 1.55 2.27

[0045] Example 2

[0046] A method for preparing an inhibitor DYL comprises the following steps:

[0047] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 1%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 1%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 2%.

[0048] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0049] Weigh 2.0g of magnesite and talc with a particle size of -74+38μm for flotation, add 30ml of deionized water to dissolve, put into a 50ml flotation tank and stir to make the mineral particles evenly dispersed in the slurry. Adjust the slurry pH to 9 and stir for 2min. Figure 1 The dosing sequence is shown. First, the inhibitor DYL is added to the slurry. The dosage of the inhibitor DYL is 100 mg / L, 150 mg / L, 200 mg / L, 250 mg / L, and 300 mg / L, respectively. The stirring time is 3 minutes. Then, 100 mg / L of the collector sodium oleate is added. The stirring time is 3 minutes. The pH value is kept constant during the dosing period. After the agent is fully effective, the foam is scraped manually for 3 minutes. The obtained foam product and the bottom product of the tank are put into the oven for drying, weighed, and the recovery rate is calculated. The results are as follows: Figure 3 shown.

[0050] Table 2 Relationship between DYL dosage and recovery of magnesite, dolomite and talc (mg / L)

[0051] 100 150 200 250 300 Magnesite 76.92 89.47 91.86 92.23 92.37 dolomite 29.7 18.66 10.4 10.25 4.26 talc 2.24 1.59 2.14 1.41 1.56

[0052] Example 3

[0053] A method for preparing an inhibitor DYL comprises the following steps:

[0054] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 1.5%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 1.5%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 3%.

[0055] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0056] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 12:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0057] Adjust the pH of the slurry to 9 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 350 mg / L of inhibitor DYL to the slurry, stir for 3 minutes, then add 50 mg / L of collector sodium oleate, stir for 3 minutes, and keep the pH value constant during the dosing. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the trough into an oven for drying, weigh, calculate the recovery rate, and test the MgO, CaO, and SiO2 content of the foam product and the bottom product of the trough, and calculate the recovery rate of MgO and SiO2 of the foam product and the bottom product of the trough. In this embodiment, the main components of the magnesite concentrate obtained by flotation experiment are 47.80% MgO, 0.17% CaO, and 0.04% SiO2 by mass percentage, and the MgO recovery rate is 93.21% by mass percentage.

[0058] Comparative Example 1

[0059] A method for using a depressant in the positive flotation of magnesite for desiliconization and calcium removal, comprising the following steps:

[0060] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 12:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0061] Adjust the pH of the slurry to 10 and stir for 2 minutes. Figure 1The dosing sequence shown is to first add 120 mg / L of water glass inhibitor and 300 mg / L of sodium hexametaphosphate to the slurry, stirring for 3 minutes respectively, then add 70 mg / L of sodium oleate collector, stirring for 3 minutes, and keep the pH value constant during the dosing. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the tank into an oven for drying, weighing, calculating the recovery rate, and testing the MgO, CaO, and SiO2 content of the foam product and the bottom product of the tank, and calculating the recovery rate of MgO and SiO2 of the foam product and the bottom product of the tank. In this comparative example, the main components of the magnesite concentrate obtained by flotation experiment are 46.12% MgO, 1.32% CaO, and 1.45% SiO2 by mass percentage, and the MgO recovery rate is 86.79% by mass percentage.

[0062] Example 4

[0063] A method for preparing an inhibitor DYL comprises the following steps:

[0064] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a 2% HCA dilute solution; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a 2% curdlan dilute solution; finally, the HCA dilute solution and the curdlan dilute solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 4%.

[0065] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 10:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0066] Adjust the pH of the slurry to 9 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 260 mg / L of inhibitor DYL to the slurry, stir for 3 minutes, then add 120 mg / L of collector oxidized paraffin soap, stir for 3 minutes, and keep the pH value constant during the dosing period. After the agent is fully effective, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the trough into an oven for drying, weigh, calculate the recovery rate, and test the MgO, CaO, and SiO2 content of the foam product and the bottom product of the trough, and calculate the recovery rate of MgO and SiO2 of the foam product and the bottom product of the trough. In this embodiment, the main components of the magnesite concentrate obtained by flotation experiment are 47.65% MgO, 0.13% CaO, and 0.22% SiO2 by mass percentage, and the MgO recovery rate is 90.88% by mass percentage.

[0067] Comparative Example 2

[0068] A method for using a depressant in the positive flotation of magnesite for desiliconization and calcium removal, comprising the following steps:

[0069] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 10:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0070] Adjust the pH of the slurry to 10 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 80 mg / L of water glass inhibitor and 250 mg / L of sodium hexametaphosphate to the slurry, stirring for 3 minutes respectively, then add 150 mg / L of oxidized paraffin soap collector, stirring for 3 minutes, and keep the pH value constant during the dosing. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the trough into an oven for drying, weighing, calculating the recovery rate, and testing the MgO, CaO, and SiO2 content of the foam product and the bottom product of the trough, and calculating the recovery rate of MgO and SiO2 of the foam product and the bottom product of the trough. In this comparative example, the main components of the magnesite concentrate obtained by flotation experiment are 46.35% MgO, 0.74% CaO, and 0.37% SiO2 by mass percentage, and the MgO recovery rate is 89.21% by mass percentage.

[0071] Example 5

[0072] A method for preparing an inhibitor DYL comprises the following steps:

[0073] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 0.5%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 0.5%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 1%.

[0074] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0075] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 7:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0076] Adjust the pH of the slurry to 9 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 240 mg / L of inhibitor DYL to the slurry, stir for 3 minutes, then add 210 mg / L of collector sodium petroleum sulfonate, stir for 3 minutes, and keep the pH value constant during the dosing period. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the tank into an oven for drying, weigh, calculate the recovery rate, and test the MgO, CaO, and SiO2 content of the foam product and the bottom product of the tank, and calculate the recovery rate of MgO and SiO2 of the foam product and the bottom product of the tank. In this embodiment, the main components of the magnesite concentrate obtained by flotation experiment are 46.93% MgO, 0.15% CaO, and 0.07% SiO2 by mass percentage, and the MgO recovery rate is 90.24% by mass percentage.

[0077] Comparative Example 3

[0078] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 7:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0079] Adjust the pH of the slurry to 10 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 420 mg / L of sodium alginate, an inhibitor, to the slurry, and stir for 3 minutes, then add 360 mg / L of sodium petroleum sulfonate, a collector, and stir for 3 minutes. The pH value is kept constant during the dosing period. After the agent is fully effective, the foam is manually scraped for 3 minutes, and the obtained foam product and the bottom product are put into an oven for drying, weighed, and the recovery rate is calculated. The MgO, CaO, and SiO2 contents of the foam product and the bottom product are tested, and the recovery rates of MgO and SiO2 of the foam product and the bottom product are calculated. In this comparative example, the main components of the magnesite concentrate obtained by flotation experiment are 46.22% MgO, 0.35% CaO, and 0.28% SiO2 by mass percentage, and the MgO recovery rate is 89.27% ​​by mass percentage.

[0080] Example 6

[0081] A method for preparing an inhibitor DYL comprises the following steps:

[0082] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 0.5%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 0.5%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 1%.

[0083] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0084] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 4:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0085] Adjust the pH of the slurry to 9 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 270 mg / L of inhibitor DYL to the slurry, stir for 3 minutes, then add 130 mg / L of collector benzohydroxamic acid, stir for 3 minutes, and keep the pH value constant during the dosing. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the trough into an oven for drying, weigh, calculate the recovery rate, and test the MgO, CaO, and SiO2 content of the foam product and the bottom product of the trough, and calculate the recovery rate of MgO and SiO2 of the foam product and the bottom product of the trough. In this embodiment, the main components of the magnesite concentrate obtained by flotation experiment are 47.29% MgO, 0.11% CaO, and 0.12% SiO2 by mass percentage, and the MgO recovery rate is 92.04% by mass percentage.

[0086] Comparative Example 4

[0087] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 4:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0088] Adjust the pH of the slurry to 10 and stir for 2 minutes. Figure 1The dosing sequence shown is to first add 75 mg / L of water glass inhibitor and 200 mg / L of sodium hexametaphosphate to the slurry, stirring for 3 minutes respectively, then add 150 mg / L of benzohydroxamic acid collector, stirring for 3 minutes, and keep the pH value constant during the dosing. After the agent fully acts, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product of the tank into an oven for drying, weighing, calculating the recovery rate, and testing the MgO, CaO, and SiO2 content of the foam product and the bottom product of the tank, and calculating the recovery rate of MgO and SiO2 of the foam product and the bottom product of the tank. In this comparative example, the main components of the magnesite concentrate obtained by flotation experiment are 46.89% MgO, 0.23% CaO, and 0.45% SiO2 by mass percentage, and the MgO recovery rate is 88.65% by mass percentage.

[0089] Example 7

[0090] A method for preparing an inhibitor DYL comprises the following steps:

[0091] The HCA solid powder is dissolved in deionized water, and after constant volume, it is configured into 50 ml of a dilute HCA solution with a mass concentration of 2.5%; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, it is configured into 50 ml of a dilute curdlan solution with a mass concentration of 2.5%. Finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed and constant volume is made to 100 ml to obtain an inhibitor DYL with a mass concentration of 5%.

[0092] A method for using a depressant DYL for positive flotation desiliconization and calcium removal of magnesite, comprising the following steps:

[0093] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 1:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0094] Adjust the pH of the slurry to 9 and stir for 2 minutes. Figure 1The dosing sequence shown is to first add 220 mg / L of inhibitor DYL to the slurry, stir for 3 minutes, then add 70 mg / L of sodium oleate and 150 mg / L of benzohydroxamic acid, stir for 3 minutes, and keep the pH value constant during the dosing. After the agent is fully effective, manually scrape the foam for 3 minutes, put the obtained foam product and the bottom product into an oven for drying, weigh, calculate the recovery rate, and test the MgO, CaO, and SiO2 content of the foam product and the bottom product, and calculate the recovery rate of MgO and SiO2 of the foam product and the bottom product. In this embodiment, the main components of the magnesite concentrate obtained by flotation experiment are 47.51% MgO, 0.09% CaO, and 0.10% SiO2 by mass percentage, and the MgO recovery rate is 88.97% by mass percentage.

[0095] Comparative Example 5

[0096] Weigh 1.6g of magnesite, 0.1g of dolomite and 0.3g of talc with a particle size range of -74+38μm respectively, mix them evenly in a ratio of 1:1:1, add 30ml of deionized water to dissolve them, put them into a 50ml flotation tank and stir them to evenly disperse the mineral particles in the slurry.

[0097] Adjust the pH of the slurry to 10 and stir for 2 minutes. Figure 1 The dosing sequence shown is to first add 280 mg / L of sodium alginate, an inhibitor, to the slurry, and stir for 3 minutes, then add 50 mg / L of sodium oleate and 100 mg / L of benzohydroxamic acid, a collector, and stir for 3 minutes. The pH value is kept constant during the dosing period. After the agent is fully effective, the foam is manually scraped for 3 minutes, and the obtained foam product and the bottom product are put into an oven for drying, weighed, and the recovery rate is calculated. The MgO, CaO, and SiO2 contents of the foam product and the bottom product are tested, and the recovery rates of MgO and SiO2 of the foam product and the bottom product are calculated. In this comparative example, the main components of the magnesite concentrate obtained by flotation experiment are 46.99% MgO, 0.14% CaO, and 0.23% SiO2 by mass percentage, and the MgO recovery rate is 89.13% by mass percentage.

Claims

1. A method for preparing an inhibitor DYL, characterized in that: The following steps are involved: The HCA solid powder is dissolved in deionized water, and after constant volume, a dilute HCA solution with a mass concentration of 0.5% to 5% is prepared; sodium hydroxide is added to the solid powder of curdlan, and after adding deionized water, it is placed in a constant temperature water bath and heated until the solid powder of curdlan is dissolved, and after constant volume, a dilute curdlan solution with a mass concentration of 0.5% to 5% is prepared; finally, the dilute HCA solution and the dilute curdlan solution with the same mass concentration are mixed at a mass ratio of 1:1 to obtain the inhibitor DYL.

2. The method for preparing an inhibitor DYL according to claim 1, characterized in that: The amount of sodium hydroxide added is 10% to 30% of the mass of the curdlan solid powder, and the temperature of the constant temperature water bath is maintained between 50°C and 90°C.

3. A method for using the inhibitor DYL according to claim 1 or 2 for direct flotation desiliconization and calcium removal of magnesite, characterized in that: The following steps are involved: S1: Take pure magnesite in the particle size range of -74+38μm, add deionized water to dissolve it, make a pulp for flotation test, and put it into the flotation tank; S2: Place the flotation cell containing the slurry on the flotation machine for stirring to make the pure mineral particles evenly distributed in the slurry; S3: Use HCl solution or NaOH solution to adjust the slurry to a set pH value, and stir it for 1 to 3 minutes under this pH condition; S4: Add the inhibitor DYL to allow the agent to fully react with the mineral surface for 1 to 3 minutes; S5: adding a collector to allow the agent to fully react with the mineral surface for 1 to 3 minutes, and keeping the pH value constant during the addition of the agent. The collector is one or two of sodium oleate, oxidized paraffin soap, sodium petroleum sulfonate, and benzohydroxamic acid; S6: After the agent has fully acted, manually scrape the foam for 3 to 5 minutes, put the obtained foam product and the product at the bottom of the tank into an oven for drying, weighing, calculating the recovery rate, and testing the MgO, CaO, and SiO2 contents.

4. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In step S1, the MgO content of pure magnesite is 43.1% to 47.8% by weight, the CaO content is 0.1% to 0.6%, the SiO2 content is 0.01% to 0.2%, the Al2O3 content is 0.1% to 0.3%, and the TFe content is 0.1%; the SiO2 content of pure talc is 61.78% to 63.37% by weight, the MgO content is 31.01% to 31.88%, the Al2O3 content is 0.1% to 0.2%, and the TFe content is 0.1%.

5. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In the step S1, the pure magnesite mineral is selected from one or more of the pure magnesite minerals of magnesite, dolomite and talc. When multiple minerals are added, the added mass ratio is magnesite: dolomite: talc = (1-16): 1:1; the concentration of the slurry is 0.050-0.080 g / mL.

6. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In step S2, the stirring speed of the flotation machine is 1900-2100 r / min; and the stirring time is 1-3 min.

7. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In step S3, the mass concentration of the HCl solution is 0.1% to 5%, and the mass concentration of the NaOH solution is 0.1% to 5%; and the pH value range is 7 to 12.

8. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In step S4, the dosage of the inhibitor DYL is 100-350 mg / L.

9. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In step S5, the dosage of sodium oleate is 33-150 mg / L, the dosage of oxidized paraffin soap is 120-150 mg / L, the dosage of sodium petroleum sulfonate is 210-360 mg / L, and the dosage of benzohydroxamic acid is 100-150 mg / L.

10. The method for using a depressant DYL for direct flotation desiliconization and calcium removal of magnesite according to claim 3, characterized in that: In the single mineral test obtained by this method, the yield of magnesite is 71.0% to 98.4%, and the yield of talc is 0.3% to 94.4%; In the test of mixed minerals obtained by this method, the concentrate yield was 62.91% to 86.79%, the MgO content was 46.9% to 47.8%, the SiO2 content was 0.1% to 0.2%, the CaO content was 0.1% to 0.2%, and the MgO recovery rate was 88.9% to 93.2%.

Images