CN111215251B

CN111215251B - Dolomite inhibitor and use method thereof

Info

Publication number: CN111215251B
Application number: CN202010164781.3A
Authority: CN
Inventors: 杨丙桥; 曾梦媛; 严海; 曾龙颜; 关智文; 贾菲菲
Original assignee: Wuhan Institute of Technology
Current assignee: SDIC XINJIANG LUOBUPO POTASH CO Ltd
Priority date: 2020-03-11
Filing date: 2020-03-11
Publication date: 2022-01-07
Anticipated expiration: 2040-03-11
Also published as: CN111215251A

Abstract

The invention discloses a dolomite inhibitor and a use method thereof, wherein the dolomite inhibitor comprises the following components in parts by mass: 80-95 parts of xanthan gum and 5-20 parts of pullulan polysaccharide, wherein the use method comprises the following steps of S1, adding water into mineral raw materials, stirring to obtain ore pulp, and adjusting the pH value of the ore pulp; s2, adding an inhibitor water solution into the ore pulp with the adjusted pH value; s3, performing air flotation to obtain a foam product and tailings, wherein the inhibitor is strong in selectivity, small in dosage, safe and non-toxic, and can effectively inhibit dolomite in the separation process of apatite and dolomite.

Description

Dolomite inhibitor and use method thereof

Technical Field

The invention belongs to the technical field of mineral separation, and particularly relates to a dolomite inhibitor and a use method thereof.

Background

Phosphorus is an important chemical raw material and is widely applied to fields of metallurgy, food, textile, medicine, national defense and the like. According to the report, the total amount of the phosphorite resources in China is proved to be the first world, but most of the phosphorite resources are middle-low grade ores, and the content of magnesium-containing carbonate is high. Magnesium carbonate-containing impurities will increase the amount of sulfuric acid used in the production of phosphoric acid, and negatively affect the filtration rate of phosphoric acid and the production efficiency of phosphoric acid, severely restricting the production of downstream phosphate products. Due to the similar surface properties of apatite and magnesium carbonate containing minerals, separation in a positive flotation circuit is difficult to achieve. The existing phosphorite demagging mainly adopts a reverse flotation process, phosphorite is inhibited under a weak acid condition, magnesium-containing carbonate minerals are floated, and then phosphorite enrichment is realized. Therefore, in the direct flotation process of phosphorite, the inhibitor mainly containing magnesium carbonate mineral dolomite can be effectively removed, and the method has very important economic value in reducing the phosphorite flotation process and reducing the production cost.

In the aspect of dolomite inhibitors, chinese patent CN103691574A reports "a preparation method and application of dolomite inhibitors" the method uses: the dolomite inhibitor is prepared from raw materials such as sulfuric acid, hydrochloric acid, benzoic acid, sulfate and the like, and the method has the advantages of long preparation time, higher medicament cost, toxicity and no contribution to large-scale production and use. Chinese patent CN87101820A reports a method for preparing a novel dolomite inhibitor calcium lignosulfonate sulfomethylated derivative for phosphorite flotation, which takes calcium lignosulfonate as a raw material, and carries out sulfomethylation reaction with formaldehyde and sodium sulfite to prepare the dolomite inhibitor in the presence of sulfuric acid after acidification and decalcification, and the preparation conditions are complex and the process flow is long. In the separation of phosphorite from dolomite, chinese patent CN108672102A reports "a flotation method of phosphorite" which uses phosphoric acid to inhibit apatite in reverse flotation, and uses collector GJBW to float dolomite to achieve mineral separation. The method reduces the consumption of sulfuric acid, but the flotation process is more complex. Chinese patent CN107029896A reports a 'flotation process for separating and enriching apatite, dolomite and quartz in phosphorite', which improves the conventional positive-negative phosphorite flotation process, and although the flotation index is improved, the flotation process is complicated.

Disclosure of Invention

The invention provides a dolomite inhibitor and a use method thereof, the dolomite inhibitor is strong in selectivity, small in dosage, safe and nontoxic for magnesium-containing carbonate mineral dolomite, and has a good effect of flotation separation of apatite and dolomite.

In order to solve the technical problems, the invention adopts the technical scheme that the dolomite inhibitor comprises the following components in parts by mass: 80-95 parts of xanthan gum and 5-20 parts of pullulan.

Preferably, the mass ratio of the xanthan gum to the pullulan is 80:20-95:5, preferably the mass ratio of the xanthan gum to the pullulan is 85:15-90:10, and more preferably the mass ratio of the xanthan gum to the pullulan is 89: 11.

Further, a use method of the dolomite inhibitor is provided, which comprises the following steps:

s1, adding water into mineral raw materials, stirring to obtain ore pulp, and adjusting the pH value of the ore pulp;

s2, adding an inhibitor water solution into the ore pulp with the adjusted pH value;

and S3, performing air flotation to obtain a foam product and tailings.

Preferably, the pH is 6.6-11.8.

Preferably, the S2 further comprises adding a collector which is at least one fatty acid collector or at least one fatty acid complexing agent.

Preferably, the concentration of the inhibitor water solution is 1-120mg/L, and the concentration of the ore pulp is 10% -50%.

Preferably, the depressants are used to suppress dolomite in apatite flotation or to suppress dolomite in other ore flotation circuits.

In the scheme, the inhibitor has a very strong inhibiting effect on magnesium carbonate mineral dolomite in phosphorite, and can realize efficient flotation separation of apatite and dolomite mainly because the inhibitor contains a large amount of carboxyl and hydroxyl groups, and because of the difference between the components of apatite and dolomite ore and the crystal structure, the carboxyl groups contained in the inhibitor are easy to expose Ca on the surface of dolomite²⁺、Mg²⁺The ions form chelate to be strongly adsorbed on the surface of the dolomite, and simultaneously, the carboxyl of the hydrophilic group is exposed in the aqueous solution, so that the surface of the dolomite is hydrophilic, and the aim of inhibiting the dolomite is fulfilled.

The beneficial effect of this scheme does:

1) the inhibitors provided by the present invention are non-toxic.

2) The inhibitor provided by the invention has the advantages of good solubility, strong selectivity, good inhibition effect, wide application pH range, small dosage and easiness in large-scale popularization.

3) The inhibitor provided by the invention has good separation effect and low separation cost.

4) The inhibitor provided by the invention is low in dosage, environment-friendly, safe to add and safe to use.

5) The inhibitor has excellent inhibiting effect on dolomite, can be used for efficiently separating apatite and dolomite, can complete the separation of the apatite and the dolomite mainly containing magnesium ore in positive flotation, can realize the reduction of flotation process flow in phosphorite flotation, and reduces the investment and production cost.

Drawings

FIG. 1 is a system and a flow chart of a flotation reagent;

FIG. 2 shows the results of an experiment in example 1 of the present invention;

FIG. 3 shows the results of an experiment in example 2 of the present invention;

FIG. 4 shows the results of an experiment in example 3 of the present invention;

FIG. 5 shows the results of the experiment in example 4 of the present invention.

Detailed Description

The present invention is described in detail below by way of examples, it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the non-essential modifications and adjustments made by those skilled in the art according to the above disclosure still belong to the scope of the present invention.

Example 1

Separately carrying out flotation on 2g of single minerals of dolomite and apatite with the granularity of +38-74 mu m, adding 50mL of distilled water into a 70mL tank-hanging flotation machine, and stirring and mixing pulp at the rotating speed of 1300r/min to fully disperse the ore pulp.

Adjusting the pH value of the ore pulp to 9, adding medicaments according to a medicament system described in figure 1, and stirring for 3min and 5min in sequence after adding the medicaments, wherein an inhibitor is xanthan gum: pullulan = 89:11 at concentrations of 0, 1, 3, 5, 8, 20, 40, 80, 120mg/L, respectively; and the collecting agent is sodium oleate (60.8 mg/L) which is stirred and then subjected to air flotation to obtain a foam product and tailings.

And respectively filtering, drying and weighing the foam product and the tailings, and calculating the floating rate, wherein the result is shown in figure 2.

As can be seen from the examples, the floating rate of apatite is slightly reduced and the floating rate of dolomite is significantly reduced with the increase of the concentration of the inhibitor, and when the concentration of the inhibitor is 8mg/L, the floating rate of apatite is as high as 89%, and the floating rate of dolomite is only 8%, indicating that the inhibition has a selective inhibition effect on dolomite.

Example 2

2g of apatite and dolomite of which the granularity is 38-74 mu m are taken for flotation respectively, 50mL of distilled water is taken and added into a 70mL tank-hanging flotation machine, and the pulp is stirred and mixed at the rotating speed of 1300r/min so as to be fully dispersed.

The adding sequence of the medicaments is shown in figure 1, 8mg/L of inhibitor (xanthan gum: pullulan = 89: 11) and collecting agent (60.8 mg/L) are sequentially added, and then the mixture is sequentially stirred for 3min and 5 min. Adjusting the pH value of the ore pulp to 6.6, 7.9, 9.0, 10.2, 11 and 11.8 before adding the medicament, and performing air flotation after stirring to obtain a foam product and tailings.

The foam product and the tailings were filtered, dried, weighed, and the flotation rate was calculated, the results are shown in fig. 3.

As is clear from the examples, the inhibitor has a pH of 7.7 to 11.8, and the apatite floating rate and the dolomite floating rate are maintained at 85% and above and 10% or below, respectively, indicating that the inhibitor has a wide range of applicable pH values.

Example 3

1.6g of apatite and 0.4g of dolomite of +38-74 mu m are respectively taken according to the proportion of 8: 2, adding 50mL of distilled water into a 70mL tank-hanging flotation machine, stirring and mixing pulp at the rotating speed of 1300r/min, and fully dispersing the pulp.

The adding sequence of the medicaments is shown in figure 1, the pH value of the ore pulp is adjusted to be 9.17 and 10.11 before the medicaments are added, the mixture is sequentially stirred for 3min and 5min after the medicaments are added, the concentration of an inhibitor (xanthan gum: pullulan = 89: 11) is 8mg/L, and a collecting agent is sodium oleate (60.8 mg/L). And (4) aerating and floating after stirring to obtain a foam product and tailings. Respectively drying the foam product and the tailings, weighing and testing P in the concentrate₅O₂MgO content, calculating P in the concentrate₅O₂And the recovery rate of MgO. The results are shown in FIG. 4.

From the examples, it is clear that at an inhibitor concentration of 8mg/L, the grade of MgO in the concentrate is reduced to 0.75 or less, while maintaining a high apatite recovery and grade.

Example 4

The adding sequence of the medicaments is shown in figure 1, the pH value of the ore pulp is adjusted to be 9.05 and 10.15 before the medicaments are added, the mixture is sequentially stirred for 3min and 5min after the medicaments are added, the concentration of an inhibitor (xanthan gum: pullulan = 89: 11) is 20mg/L, and a collecting agent is sodium oleate (91.3 mg/L). And (4) aerating and floating after stirring to obtain a foam product and tailings. Respectively drying the foam product and the tailings, weighing and testing P in the concentrate₅O₂MgO content, calculating P in the concentrate₅O₂And the recovery rate of MgO. The results are shown in FIG. 5.

From the examples, it is clear that the grade of MgO in the concentrate is reduced to 0.65 or less at an inhibitor concentration of 20mg/L, while maintaining a high apatite recovery and grade.

Example 5

The adding sequence of the agents is shown in figure 1, the pH value of the ore pulp is adjusted to be 12 before the agents are added, the agents are sequentially stirred for 3min and 5min after the agents are added, the concentration of the inhibitor is 120mg/L, and the mass ratio of xanthan gum to pullulan is respectively 80:20 and 95: 5. 85:15, 90:10 and the collector is sodium oleate (60.8 mg/L). Aerating and floating after stirring to obtain foam products and tailings, respectively filtering, drying, weighing and testing P in the concentrate₅O₂MgO containingAnd the floating rate is calculated, the floating rates of the apatite are respectively 70%, 60%, 65% and 68%, and the floating rates of the dolomite are respectively 6%, 3%, 5% and 2%, which shows that the inhibition has selective inhibition effect on the dolomite.

The contents of the present invention are not limited to the above-described embodiments, and other embodiments within the technical teaching of the present invention by those skilled in the art are within the scope of the present invention.

Claims

1. The dolomite inhibitor is characterized by comprising the following components in parts by weight: 80-95 parts of xanthan gum and 5-20 parts of pullulan.

2. A dolomite inhibitor according to claim 1, wherein the mass ratio of xanthan gum to pullulan is 80:20-95: 5.

3. A dolomite inhibitor according to claim 2, wherein the mass ratio of xanthan gum to pullulan is from 85:15 to 90: 10.

4. A dolomite inhibitor according to claim 3, wherein the mass ratio of xanthan gum to pullulan is 89: 11.

5. A method of using a dolomite inhibitor according to claim 1, comprising the steps of:

and S3, performing air flotation to obtain a foam product and tailings.

6. A method of use of a dolomite inhibitor according to claim 5, wherein the pH is from 6.6 to 11.8.

7. A method of using a dolomite inhibitor according to claim 5, wherein the S2 further includes adding a collector which is at least one fatty acid type collector or at least one fatty acid type complexing agent.

8. A method of use of a dolomite inhibitor according to claim 5, wherein the concentration of the aqueous inhibitor solution is 1-120 mg/L.

9. A method of using a dolomite inhibitor according to claim 5, wherein the inhibitor is used to inhibit dolomite in apatite flotation or in other ore flotation circuits.