CN115646656A - A kind of activation method and application of optimizing mechanically activated starch inhibitor - Google Patents

Abstract

The invention discloses an activation method and application for optimizing mechanically activated starch inhibitors, including the following steps: S1. Using starch as a raw material, by adjusting the set of mechanical activation parameters, the starch raw material is charged to obtain mechanical activation under different parameter conditions. Activate the starch inhibitor, and calculate the charging energy value of each mechanically activated starch inhibitor by the charging energy formula (I),

S2. Using mechanically activated starch as an inhibitor, carry out flotation experiments on minerals respectively, and record the flotation recovery rate; S3. Fit the corresponding charging energy value and flotation recovery rate through SPSS to obtain the recovery rate-charging formula (II), ε=αE ² +βE+γ(II); S4. Calculate the charging energy value E _i through the recovery rate-charging formula (II), and bring E _i into the charging energy formula (Ⅰ) to determine A set of mechanical activation parameters, the starch inhibitor prepared by using the determined parameters has strong reactivity and high inhibitory mineral flotation efficiency.

Description

A kind of activation method and application of optimizing mechanically activated starch inhibitor

technical field

The invention relates to the technical field of mineral processing, in particular to an activation method and application for optimizing a mechanically activated starch inhibitor.

Background technique

There are limited varieties of natural starch, and there are disadvantages such as insolubility in cold water, poor thermal stability of paste, low shear resistance, easy dehydration after cold, easy aging, poor film formation and lack of water resistance. At the same time, new processes, The scope of application of new equipment and new technologies is limited, and it can no longer meet the needs of the growing modern technology and equipment. Therefore, starch needs to be denatured.

Starch denaturation is the use of physical, chemical or biological means to change the properties of native starch, through molecular cutting, rearrangement, oxidation or the introduction of substituents in starch molecules to obtain starch derivatives with changed properties, that is, modified starch. To increase its performance or introduce new features, overcome the defects in application, and meet the needs of modern industrial production; physical means include mechanical activation, which means that the item will produce lattice distortion and local destruction under the action of mechanical force, and form various Defects lead to the increase of its internal energy and the process of enhanced reactivity.

As a natural macromolecular compound, starch is often used as an inhibitor in mineral flotation, that is, to selectively inhibit the flotation of certain minerals, expand the difference in floatability between different minerals, and improve the efficiency of flotation and separation. However, the existing research has not yet clarified the effect of mechanical activation on the ability of starch molecules to inhibit mineral flotation, and there is no application of mechanically activated modified starch in the field of mineral flotation. Therefore, it is necessary to explore the effect of mechanical activation conditions on the inhibitory ability of starch molecules, and to clarify the optimal process conditions for the preparation of starch inhibitors, so that their separation efficiency in mineral flotation applications can be improved.

Contents of the invention

In view of this, the present application provides an activation method and application of an optimized mechanically activated starch inhibitor. The starch inhibitor prepared by the determined parameters has high activity and high mineral separation efficiency.

In order to achieve the above-mentioned technical purpose, the application adopts the following technical solutions:

In a first aspect, the application provides a method for optimizing the activation of mechanically activated starch inhibitors, comprising the following steps:

S1. Using starch as a raw material, adjust the mechanical activation parameter set of the planetary mill, and perform a dry mechanical activation solid-phase reaction to charge the starch raw material, obtain mechanically activated starch inhibitors under different parameter conditions, and calculate each mechanically activated starch Inhibitor charge energy value;

S2. Using mechanically activated starch as an inhibitor, carry out flotation experiments on minerals respectively, and record the flotation recovery rate;

S3. Fit the corresponding charging energy value and flotation recovery rate through SPSS to obtain the recovery rate-charging formula (II),

ε=αE ² +βE+γ(II),

Among them, ε is the flotation recovery rate; α, β, γ are constants determined by the type of starch;

S4. Calculate the optimal charging energy value E _i through the recovery rate-charging formula (II), and bring E _i into the charging energy formula (I) to determine the optimal mechanical activation parameter set;

S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor.

Preferably, in step S4, the optimal charging energy value E _i is calculated by deriving the recovery rate-charging formula (II) to be equal to zero, and obtaining the extreme value is the optimal charging energy value E _i .

Preferably, the starch raw material includes one or more of corn starch, potato starch, glutinous rice starch, rice starch and the like.

Preferably, in step S4, the mechanical activation parameter set includes three parameters: ball-to-material ratio, planetary mill speed, and activation time; the optimal charge energy value E _i is brought into the charge energy formula (I), based on the mechanical activation parameters Any two parameters in the set are calculated to obtain the remaining one parameter, and the obtained three parameters are recorded as the optimal mechanical activation parameter set.

Preferably, in step S1, the charging energy value ranges from 2.6KJ to 32KJ.

Preferably, the steps of the flotation experiment are: add deionized water to the ore sample to be flotation, and adjust the pH to alkaline, add the aqueous solution of mechanically activated starch inhibitor, after stirring, add the collector, stir, Flotation scraping, filtering the product in the tank, drying and weighing to obtain the grade and recovery rate of the flotation concentrate.

Preferably, the charging energy value is calculated by the charging energy formula (I),

Among them, E is the charging energy, f is the starch activation index, τ is the pellet ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, and T is the activation time.

In a second aspect, the present application provides a mechanically activated starch inhibitor.

In a third aspect, the present application provides an application of a mechanically activated starch inhibitor in mineral sorting.

Preferably, the minerals include one or more of hematite, barite, kaolinite and the like.

The beneficial effects of the application are as follows:

In the present invention, the charging energy formula and the recovery rate-charging formula can control the quality of the starch inhibitor, obtain the mechanically activated starch product with the best inhibitory effect, and can determine the combination of the optimal input energy of the mechanically activated starch and the optimal mechanical activation conditions , optimize the preparation process of starch inhibitor;

Through the method of the present invention, the starch inhibitor obtained can be precisely controlled by adjusting the planetary milling time, the number of revolutions, and the ball-to-material ratio. Without destroying the internal structure of the starch, the starch can obtain activation characteristics, increase its solubility, and reduce the gelatinization of the starch. temperature and settling;

The obtained starch inhibitor is used in mineral flotation. Due to the high reactivity of mechanically activated starch, it effectively improves its ability to interact with the surface of some minerals during flotation, making the mineral hydrophilic and hindering the collection of collectors. Combined, thereby selectively reducing the flotation recovery rate of some minerals, and improving the separation efficiency.

Description of drawings

Fig. 1 is the effect comparison figure of the cornstarch inhibitor prepared under the condition of different mechanical activation time to the flotation recovery rate of hematite;

Fig. 2 is the effect comparison figure of the effect of corn starch inhibitor on the flotation recovery rate of hematite under different planetary ball mill rotating speed conditions;

Fig. 3 is the comparative figure of the action result of the flotation recovery rate of the cornstarch inhibitor prepared under different pellet ratio conditions to hematite;

Fig. 4 is the rate of recovery of cornstarch inhibitor-charging formula function relation figure;

Figure 5 is the technical roadmap of this solution.

Detailed ways

In order to make the object, technical solution and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Terminology Explanation

"Starch activation index" refers to the conversion efficiency of different starches for mechanical activation and charging, which is determined by the properties of each starch itself;

"The unit energy consumption of the planetary mill" refers to the rated power of the selected planetary mill instrument;

"Energizing energy" refers to the input energy obtained by converting the starch raw material through the mechanical activity energy conversion of the planetary mill.

As known to those skilled in the art, mechanical activation refers to a process in which an item undergoes lattice distortion and local destruction under the action of mechanical force, and forms various defects, resulting in an increase in its internal energy and enhanced reactivity. With the continuous update and iteration of mechanical activation equipment, the control of the input energy of the item is becoming more and more accurate, easier to calculate, and easier to simulate and fit. Therefore, mechanical activation equipment can control the quality of the finished product, which provides an idea for obtaining the best activated product and determining the best input energy for the item.

The applicant found that mechanical activation can strengthen the activity of starch hydroxyl functional groups and change and optimize the interaction structure between starch molecules and mineral surfaces, while excessive energy input will weaken the chain structure of starch molecules and greatly reduce its inhibitory ability. The formula obtained by data fitting can be reversed to obtain the optimal activation parameters, control the quality of the starch inhibitor, and obtain the mechanically activated starch product with the best inhibition effect, and can determine the optimal input energy and the best mechanical activation conditions for mechanically activated starch, optimize Preparation process of starch inhibitor.

Based on the above, the present invention has been established.

The application provides a method for optimizing the activation of mechanically activated starch inhibitors, as shown in Figure 5, comprising the following steps:

S1. Use starch as raw material, weigh it and put it in the zirconia tank of the planetary mill for standby, set the parameters of the planetary mill, and perform mechanical activation: adjust the rotation number, time and ball-to-material ratio of the planetary mill to mechanically activate and charge the starch. Prepare different starch inhibitors for use; the above mechanical activation process is the process of dry ball milling, which can charge the starch raw material, and calculate the corresponding charging energy value according to the charging energy formula (I) according to different planetary milling parameters E ₁ , E ₂ , E ₃ , E ₄ , E ₅ , E ₆ ...,

Among them, E is the charging energy, f is the starch activation index, τ is the pellet ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, and T is the activation time;

S2. take the obtained starch inhibitor as solute, and deionized water as solvent, configure 0.8g/L starch inhibitor solution; use above-mentioned starch inhibitor solution as inhibitor to carry out flotation separation to different minerals, comprising the following steps ( Hematite flotation as an example): put 2g hematite (200-400 mesh) into the flotation cell, add 25ml deionized water and stir for 2 minutes to form a slurry, adjust the pH of the slurry to 10, stir for 2 minutes, add mechanical activation Aqueous solution of starch inhibitor (2ml), so that the concentration of starch inhibitor in the flotation tank is 40mg/L, after stirring for 2min, add 1mL of 1.6g/L dodecylamine collector, stir for 2min, then add 2 drops of foaming After flotation and scraping, the minerals in the tank are filtered, dried, weighed, and the weighing data is recorded. The recovery rate is the mass ratio of the concentrate quality in the tank to the mass ratio of the ore sample to be weighed to be flotation. Corresponding dressing recovery ε ₁ , ε ₂ , ε ₃ , ε ₄ , ε ₅ , ε ₆ ...;

S3. Collect the charging energy values E ₁ , E ₂ , E ₃ , E ₄ , E ₅ , E ₆ ... obtained under different parameter conditions in step S1, and collect the beneficiation recovery rate ε ₁ of the starch inhibitor corresponding to the charging energy _{. _ _ _ _}

ε=αE ² +βE+γ(II),

Among them, ε is the flotation recovery rate; α, β, γ are the constants of the recovery rate-charging formula, which change with the change of starch;

S4. Calculate the optimal charging energy value E _i through the recovery rate-charging formula (II), the calculation method of the optimal charging energy value E _i is to derivate the recovery rate-charging formula (II) equal to zero, and solve The extreme value is taken as the optimal charging energy value E _i , and E _i is brought into the charging energy formula (Ⅰ) to deduce the optimal mechanical activation parameter set. During the deduction process, two of the three parameters are set to For quantification within the range to determine the value of the remaining parameters: calculate the remaining one parameter based on any two parameters in the mechanical activation parameter set, and record the obtained three parameters as the best mechanical activation parameter set.

S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor.

In order to verify whether the theory matches the actual application, the appropriate mechanical activation conditions corresponding to this scheme were prepared to prepare the starch inhibitor, and the flotation experiment was carried out according to the same conditions in step S2 to check the flotation recovery rate and verify the recovery rate-charging According to the accuracy of the formula, in this scheme, the goodness of fit of the energy charging formula and the recovery rate-charging formula is greater than 0.9.

The charging energy formula (I) and recovery rate-charging formula (II) of this scheme provide theoretical support for the selection of the preparation parameters of the starch inhibitor, and play a vital role in the preparation process of the starch inhibitor: First, Improve the quality of starch inhibitors to obtain mechanically activated starch products with the best inhibitory effect; the second is to determine the optimal input energy for mechanically activated starch, correspondingly select the optimal mechanical activation conditions, and optimize the preparation process of starch inhibitors. Mechanically activated starch can be used as an inhibitor in the flotation of various minerals to effectively separate target minerals and gangue minerals.

Starch raw materials include one or more of corn starch, potato starch, glutinous rice starch, rice starch, etc. Different starch raw materials correspond to different starch inhibitors. For example, through the above step S1, corn starch (NS) raw materials are dry-processed Mechanically activated solid phase reaction to obtain mechanically activated corn starch (NST) and waxy rice starch (WS) Starch raw materials were mechanically activated by dry solid state reaction to obtain mechanically activated glutinous rice starch (WST), and G50 transgenic corn starch was obtained by dry mechanically activated solid phase reaction The mechanically activated G50 transgenic cornstarch (G50T) was obtained, and the G80 transgenic cornstarch was mechanically activated and solid-phase reacted to obtain the mechanically activated G80 transgenic cornstarch (G80T).

It is worth noting that in the charging energy formula (I), f is the starch activation constant, which refers to the conversion efficiency of different starches for mechanical activation and charging, which is determined by the properties of each starch itself. For example, the starch constant f of ordinary corn is 1.26 ; e _i is the unit energy consumption of the planetary mill, which is obtained through the power conversion of the selected planetary mill instrument. In this application, the used planetary mill is the German Feichi Group, Pulverisette 6 series planetary ball mill, and its unit energy consumption is 1.2 J/c, c is the number of circles that the planetary ball mill rotates during operation; other parameters are variables, such as τ, N, T, and are adjusted according to actual needs, for example, in some specific embodiments , select a zirconia jar with an inner diameter of 5cm and a volume of 50ml, the diameter of the ball mill in the ball mill is 1cm, and the material of the ball is zirconia. In this scheme, the rotational speed of the planetary mill is 200-600r/min, which is suitable but not restrictive. For example 200r/min, 300r/min, 400r/min, 500r/min, 600r/min, the ball-to-material ratio is 15:1, 20:1 or 30:1, the activation time is 10-120min, suitable but not limited , for example, 10min, 20min, 30min, 40min, 50min, 80min, 90min, 120min, due to excessive mechanical activation charging, exceeding the threshold value of starch tolerance, the starch structure will be destroyed, reducing the effect of inhibitors, mechanical activation charging If it is too low, the purpose of starch activation cannot be achieved. Therefore, in this plan, the range of mechanical activation charging energy determined by each mechanical activation condition is: 2.6KJ-32KJ, based on the set mechanical activation charging energy range , adjust the values of the three variable parameters, and calculate the charging energy value E under different conditions through the charging energy formula (Ⅰ);

Taking ordinary cornstarch as an example, the recovery rate-charging formula obtained according to the above steps is: ε=0.002E ² -0.043E+0.24, by taking the extreme value of the above formula, the flotation recovery rate is 1%, and the charging E is 10.75KJ, the effect of starch inhibitor is the best, that is, the optimal input energy for mechanical activation of starch is 10.75KJ, and one of the optimal mechanical activation conditions that can be determined by charging energy formula (I) is: rotation speed 400r/min, activation time For 20min, the pellet ratio is 15:1. In order to verify the accuracy of the formula, the recovery rate-charging formula is obtained to determine the optimal input energy of mechanically activated starch, and a highly active starch inhibitor is obtained. The starch inhibitor is applied to In the flotation experiment of the hematite of this scheme, the hematite flotation recovery rate obtained under the low-concentration inhibitor dosage is <1%, which shows that the formula provided by this method has high accuracy;

The present application provides a mechanically activated starch inhibitor.

This application provides an application of a mechanically activated starch inhibitor in mineral sorting efficiency. Minerals include one or more of hematite, barite, kaolinite, etc., which reduces the buoyancy of some minerals, and To expand the difference in floatability between different minerals, the application steps are as follows: use the obtained starch inhibitor as the solute and deionized water as the solvent to prepare a 0.8g/L starch inhibitor solution; use the above starch inhibitor solution as the inhibitor Different minerals are separated by flotation, including the following steps (hematite flotation as an example): add 2g hematite (200-400 mesh) into the flotation cell, add 25ml deionized water and stir for 2min to form a slurry, and put Adjust the pH of the pulp to 10, stir for 2 minutes, add an aqueous solution (2ml) of mechanically activated starch inhibitor to make the concentration of the starch inhibitor in the flotation tank 40mg/L, stir for 2min, then add 1mL of 1.6g/L dodecylamine Collecting agent, stirred for 2 minutes, then added 2 drops of foaming agent, after flotation and scraping, the minerals in the tank were filtered, dried, weighed, and the weighing data was recorded. The recovery rate was equal to the weight of the concentrate in the tank and the The mass ratio of the ore sample to be flotation is calculated to obtain the corresponding recovery rate of ore dressing, and then the effect of starch inhibitor can be analyzed.

The scheme will be further described below in conjunction with specific examples.

Example 1

An activation method for optimizing mechanically activated starch inhibitors, comprising the following steps:

S1. Preparation of Mechanically Activated Starch Inhibitor and Calculation of Charging Energy

Take by weighing 4g cornstarch (NS), be placed in the planetary mill zirconia tank for subsequent use;

According to the planetary mill parameters set by the experimental group 1-5, the dry mechanical activation of the starch raw materials was carried out: the activation time was used as a variable, and the corn starch (NS) was mechanically activated by the planetary mill at room temperature at a speed of 400r/min. 10min, 15min, 25min, 30min, 60min, the ratio of grinding balls to cornstarch (NS) balls is 15:1, after the mechanical ball milling process, calculate the corresponding charging energy value according to the charging energy formula (I):

Among them, E is the charging energy, f is the starch activation index, τ is the ball-to-material ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, T is the activation time, f and e _i are constants, and f is Cornstarch (NS) activation index, its value is 1.26, e _i is the unit energy consumption of planetary mill, its value is 1.2J/c, according to the different ball-to-material ratios set by experimental groups 1-5, activation time, Rotating speed of planetary mill, different common corn activated starch inhibitors are obtained, the calculated charging energy is respectively 5.376KJ, 8.064KJ, 13.44KJ, 16.128KJ, 32.256KJ mechanically activated cornstarch (NS), in the present embodiment, oxidation The inner diameter of the zirconium tank is 4cm, and the volume is 50ml; the diameter of the grinding ball in the zirconia tank is 1cm, and the material of the grinding ball is zirconia.

S2. Flotation test, record experimental data

The different ordinary corn activated starch inhibitors obtained in step S1 are tested according to the mineral flotation test, and the recovery rate is tested to obtain the recovery rate ε. The flotation test steps are as follows:

Take by weighing 0.08g starch and take deionized water as solvent, configure 0.8g/L starch inhibitor solution; Use above-mentioned starch inhibitor solution as inhibitor to carry out flotation separation to different minerals, comprise the following steps (hematite flotation For example): add 2g hematite (200-400 mesh) into the flotation cell, add 25ml deionized water and stir for 2 minutes to form a slurry, adjust the pH of the slurry to 10, stir for 2 minutes, add the aqueous solution of mechanically activated starch inhibitor (2ml), so that the starch inhibitor concentration in the flotation tank is 40mg/L, after stirring for 2min, add 1mL of 1.6g/L dodecylamine collector, stir for 2min, then add 2 drops of foaming agent, after flotation Scrape, filter, dry, and weigh the minerals in the tank, record the weighing data, the recovery rate is the mass ratio of the concentrate mass in the tank to the weighed ore sample to be flotation, and calculate the corresponding flotation recovery rate, and the results are shown in Figure 1.

S3.SPSS fits the recovery rate and charging data to obtain the recovery rate-charging formula

The parameters in step S1, the charging energy (E) calculated under different parameter conditions, and the flotation recovery rate (ε) corresponding to the records in step S2 are sorted out to obtain Table 1:

The parameter of table 1 corn starch (NS) inhibitor

category number of items τ N(r/min) T(min) E(J) ε(%) Experimental group 1 1 15 400 10 5376 19 Experimental group 2 2 15 400 15 8064 9 Experimental group 3 3 15 400 25 13440 8 Experimental group 4 4 15 400 30 16128 16 Experimental group 5 5 15 400 60 322560 twenty two best fit group 6 15 400 20 10752 1

The charging energy energy (E) and the flotation recovery rate (ε) in the above data were fitted by SPSS, and the results are shown in Figure 4. The fitting relationship between the inhibition recovery rate and the charging energy of common corn activated starch was obtained as : ε=0.002E ² -0.043E+0.24, which is the general corn starch recovery rate-charging formula, goodness of fit R ² =0.98, goodness of fit R ² ≥0.9.

S4. Determine the optimal charging energy value E _i and the optimal mechanical activation parameter set,

S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor.

Through the recovery rate-charging formula, deriving the extreme value to obtain the optimal charging energy value is 10750KJ. In this embodiment, only the activation time is a variable, and the ball-to-material ratio and planetary mill speed are quantitative, which is brought into the charging energy formula (I) calculation, the best mechanical activation time is 20min. .

Verify the validity of the formula

Prepare the mechanically activated starch inhibitor according to the optimal mechanical activation parameter set determined in step S4, and carry out the flotation experiment with the starch activated inhibitor. The performance is high, and the parameter combination in the above-mentioned optimal fitting group is the combination of the best mechanical activation parameter set.

Example 2

An activation method for optimizing mechanically activated starch inhibitors, comprising the following steps:

S1. Preparation of Mechanically Activated Starch Inhibitor and Calculation of Charging Energy

Take by weighing 4g cornstarch (NS), be placed in the planetary mill zirconia tank for subsequent use;

According to the planetary mill parameters set by the experimental group 6-11, the dry mechanical activation of the starch raw materials was carried out: the speed of the planetary mill was used as a variable, and the planetary mill was used at room temperature under the condition of a ball milling time of 20 minutes, respectively at a speed of 200r/min, 300r Under the conditions of /min, 350r/min, 450r/min, 500r/min, 600r/min, mechanically activate the corn starch (NS) for 20 minutes, the ratio of balls to corn starch (NS) is 15:1, and the mechanical ball milling process is over After that, calculate the corresponding charging energy value according to the charging energy formula (I):

Among them, E is the charging energy, f is the starch activation index, τ is the ball-to-material ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, T is the activation time, f and e _i are constants, and f is Corn starch (NS) activation index, its value is 1.26, e _i is the unit energy consumption of the planetary mill, its value is 1.2J/c, according to the different ball-to-material ratios set by experimental group 6-11, activation time, Rotating speed of planetary mill, different common corn activated starch inhibitors are obtained, the calculated charging energy is respectively 5.376KJ, 8.064KJ, 10.752KJ, 13.440KJ, 16.128KJ mechanically activated cornstarch (NS), in the present embodiment, oxidation The inner diameter of the zirconium tank is 4cm, and the volume is 50ml; the diameter of the grinding ball in the zirconia tank is 1cm, and the material of the grinding ball is zirconia.

S2. Flotation test, record experimental data

The different ordinary corn activated starch inhibitors obtained in step S1 are tested according to the mineral flotation test, and the recovery rate is tested to obtain the recovery rate ε. The flotation test steps are as follows:

Take by weighing 0.08g starch and take deionized water as solvent, configure 0.8g/L starch inhibitor solution; Use above-mentioned starch inhibitor solution as inhibitor to carry out flotation separation to different minerals, comprise the following steps (hematite flotation For example): add 2g hematite (200-400 mesh) into the flotation cell, add 25ml deionized water and stir for 2 minutes to form a slurry, adjust the pH of the slurry to 10, stir for 2 minutes, add the aqueous solution of mechanically activated starch inhibitor (2ml), so that the starch inhibitor concentration in the flotation tank is 40mg/L, after stirring for 2min, add 1mL of 1.6g/L dodecylamine collector, stir for 2min, then add 2 drops of foaming agent, after flotation Scrape, filter, dry, and weigh the minerals in the tank, record the weighing data, the recovery rate is the mass ratio of the concentrate mass in the tank to the weighed ore sample to be flotation, and calculate the corresponding flotation recovery rate, and the results are shown in Figure 2.

S3.SPSS fits the recovery rate and charging data to obtain the recovery rate-charging formula

The parameters in step S1, the charging energy (E) calculated under different parameter conditions, and the flotation recovery rate (ε) corresponding to the records in step S2 are sorted out to obtain Table 2:

The parameter of table 2 corn starch (NS) inhibitor

category τ N(r/min) T(min) E(J) ε(%) Experimental group 1 15 200 20 5376 18 Experimental group 2 15 300 20 8064 9 Experimental group 3 15 350 20 9408 8 Experimental group 4 15 450 20 12096 10 Experimental group 5 15 500 20 13440 16 Experimental group 6 15 600 20 16128 twenty two best fit group 15 400 20 10752 1

The charging energy energy (E) and the flotation recovery rate (ε) in the above data were fitted by SPSS, and the results are shown in Figure 4. The fitting relationship between the inhibition recovery rate and the charging energy of common corn activated starch was obtained as : ε=0.002E ² -0.043E+0.24, which is the general corn starch recovery rate-charging formula, goodness of fit R ² =0.98, goodness of fit R ² ≥0.9.

S4. Determine the optimal charging energy value E _i and the optimal mechanical activation parameter set

Through the recovery rate-charging formula, deriving the extreme value to obtain the optimal charging energy value is 10750KJ. In this embodiment, only the rotation speed of the planetary mill is a variable, and the ball-to-material ratio and activation time are quantitative, which is brought into the charging energy formula (I) calculation, the best planetary ball mill speed is 400r/min.

S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor.

Verify the validity of the formula

Prepare the mechanically activated starch inhibitor according to the optimal mechanical activation parameter set determined in step S4, and carry out the flotation experiment with the starch activated inhibitor. High performance, the parameter combination in the above-mentioned optimal fitting group 1 is the combination of the best mechanical activation parameter set

Example 3

An activation method for optimizing mechanically activated starch inhibitors, comprising the following steps:

S1. Preparation of Mechanically Activated Starch Inhibitor and Calculation of Charging Energy

Take by weighing 4g cornstarch (NS), be placed in the planetary mill zirconia tank for subsequent use;

Carry out dry mechanical activation of starch raw materials according to the planetary mill parameters set by experimental groups 12-15: use the ball-to-material ratio as a variable, use a planetary mill at room temperature to mechanically activate corn starch (NS) at a speed of 400r/min For 20 minutes, the ball-to-material ratio of grinding balls and cornstarch (NS) is 10:1, 20:1, 30:1. After the mechanical ball milling process, calculate the corresponding charging energy value according to the charging energy formula (Ⅰ):

Among them, E is the charging energy, f is the starch activation index, τ is the ball-to-material ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, T is the activation time, f and e _i are constants, and f is Cornstarch (NS) activation index, its value is 1.26, e _i is the unit energy consumption of planetary mill, its value is 1.2J/c, according to the different ball-to-material ratios set by experimental group 12-15, activation time, Planetary mill speed, different common corn activated starch inhibitors are obtained, and the calculated charging energy is respectively 10.842KJ, 10.584KJ, 10.416KJ mechanically activated cornstarch (NS). In this embodiment, the inner diameter of the zirconia tank is 4cm, and the volume 50ml; the diameter of the grinding ball in the zirconia tank is 1cm, and the material of the grinding ball is zirconia.

S2. Flotation test, record experimental data

The different ordinary corn activated starch inhibitors obtained in step S1 are tested according to the mineral flotation test, and the recovery rate is tested to obtain the recovery rate ε. The flotation test steps are as follows:

Take by weighing 0.08g starch and take deionized water as solvent, configure 0.8g/L starch inhibitor solution; Use above-mentioned starch inhibitor solution as inhibitor to carry out flotation separation to different minerals, comprise the following steps (hematite flotation For example): add 2g hematite (200-400 mesh) into the flotation cell, add 25ml deionized water and stir for 2 minutes to form a slurry, adjust the pH of the slurry to 10, stir for 2 minutes, add the aqueous solution of mechanically activated starch inhibitor (2ml), so that the starch inhibitor concentration in the flotation tank is 40mg/L, after stirring for 2min, add 1mL of 1.6g/L dodecylamine collector, stir for 2min, then add 2 drops of foaming agent, after flotation Scrape, filter, dry, and weigh the minerals in the tank, record the weighing data, the recovery rate is the mass ratio of the concentrate mass in the tank to the weighed ore sample to be flotation, and calculate the corresponding flotation recovery rate, and the results are shown in Figure 3.

S3.SPSS fits the recovery rate and charging data to obtain the recovery rate-charging formula

The parameters in step S1, the charging energy (E) calculated under different parameter conditions, and the flotation recovery rate (ε) corresponding to the records in step S2 are sorted out to obtain Table 3:

The parameter of table 3 corn starch (NS) inhibitor

category τ N(r/min) T(min) E(J) ε(%) Experimental group 1 10 200 20 10842 18 Experimental group 2 20 300 20 10584 9 Experimental group 3 30 350 20 10416 16 best fit group 15 400 20 10752 1

The charging energy energy (E) and the flotation recovery rate (ε) in the above data were fitted by SPSS, and the results are shown in Figure 4. The fitting relationship between the inhibition recovery rate and the charging energy of common corn activated starch was obtained as : ε=0.002E ² -0.043E+0.24, which is the general corn starch recovery rate-charging formula, goodness of fit R ² =0.98, goodness of fit R ² ≥0.9.

S4. Determine the optimal charging energy value E _i and the optimal mechanical activation parameter set

Through the recovery rate-charging formula, deriving the extreme value to obtain the optimal charging energy value is 10750KJ. In this embodiment, only the ball material ratio is a variable, and the activation time and planetary mill speed are quantitative, which is brought into the charging energy formula (I) calculation, the best ball-to-material ratio is 15:1.

To sum up the above examples 1-3, the optimal mechanical activation conditions are: mechanical activation time 20min, planetary ball mill speed 400r/min, ball-to-material ratio 15:1.

S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor.

Verify the validity of the formula

Prepare the mechanically activated starch inhibitor according to the optimal mechanical activation parameter set determined in step S4, and carry out the flotation experiment with the starch activated inhibitor. The performance is high, and the parameter combination in the above-mentioned optimal fitting group is the combination of the best mechanical activation parameter set.

Example 4-6

By changing the starch raw materials to WS, G50, and G80, and repeating the above steps, the optimal mechanical activation time of WS is 10 minutes, the optimal planetary ball mill speed is 400r/min, and the optimal ball-to-material ratio is 15:1; the optimal mechanical activation time of G50 is obtained. The mechanical activation time is 20min, the optimal planetary ball mill speed is 500r/min, and the optimal ball-to-material ratio is 15:1; the optimal mechanical activation time of G80 is 30min, the optimal planetary ball mill speed is 400r/min, the optimal The ball to material ratio is 15:1.

In this application, through the mechanical activation of NS, WS, G50 and G80 through planetary ball milling for a short period of time, the chemical reactivity of activated NST, WST, G50T and G80T is improved, and the chemical adsorption capacity with minerals is improved during flotation, so that Minerals are hydrophilic and hinder the combination of minerals and collectors, and mechanically activated starch acts as an inhibitor, which greatly reduces the recovery rate of flotation.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention, All should be covered within the protection scope of the present invention.

Claims (10)

1. an activation method for optimizing mechanically activated starch inhibitor, is characterized in that, comprises the following steps: S1. Using starch as a raw material, adjust the mechanical activation parameter set of the planetary mill, and perform a dry mechanical activation solid-phase reaction to charge the starch raw material, obtain mechanically activated starch inhibitors under different parameter conditions, and calculate each mechanically activated starch Inhibitor charge energy value; S2. Using the mechanically activated starch as an inhibitor, carry out flotation experiments on minerals respectively, and record the flotation recovery rate; S3. Fit the corresponding charging energy value and flotation recovery rate through SPSS to obtain the recovery rate-charging formula (II), ε=αE ² +βE+γ (Π), Among them, ε is the flotation recovery rate; α, β, γ are constants determined by the type of starch; S4. Calculate the optimal charging energy value E _i through the recovery rate-charging formula (II), and bring E _i into the charging energy formula (I) to determine the optimal mechanical activation parameter set; S5. Based on the optimal set of mechanical activation parameters, prepare a mechanically activated starch inhibitor. 2. the activation method of optimization mechanically activated starch inhibitor according to claim 1, is characterized in that, in step S4, the computing method of optimal charging energy value E _is , with described rate of recovery-charging formula ( Ⅱ) The derivation is equal to zero, and the extreme value of the solution is the optimal charging energy value E _i . 3. the activation method of optimization mechanically activated starch inhibitor according to claim 1, is characterized in that, described starch raw material comprises one or more in cornstarch, potato starch, glutinous rice starch, rice starch. 4. the activation method of optimization mechanical activation starch inhibitor according to claim 1, is characterized in that, in step S4, described mechanical activation parameter set comprises three parameters of ball material ratio, planetary mill rotating speed, activation time; The above optimal charging energy value E _i is brought into the charging energy formula (I), and the remaining parameter is calculated based on any two parameters in the mechanical activation parameter set, and the obtained three parameters are recorded as Optimal set of mechanical activation parameters. 5. The activation method for optimizing mechanically activated starch inhibitor according to claim 1, characterized in that, in step S1, the charging energy value ranges from 2.6KJ to 32KJ. 6. the activation method of optimization mechanically activated starch inhibitor according to claim 1, is characterized in that, the step of described flotation experiment is, adds deionized water in the ore sample to be flotation, and adjusts pH to alkali properties, add the aqueous solution of the mechanically activated starch inhibitor, after stirring, then add the collector, stir, flotation scrape, filter the product in the tank, dry, weigh, and obtain the grade and recovery rate of the flotation concentrate . 7. the activation method of optimization mechanically activated starch inhibitor according to claim 1, is characterized in that, charging energy value is calculated by charging energy formula (I),

Among them, E is the charging energy, f is the starch activation index, τ is the pellet ratio, e _i is the unit energy consumption of the planetary mill, N is the rotational speed of the planetary mill, and T is the activation time. 8. The mechanically activated starch inhibitor prepared by the method according to any one of claims 1-7. 9. The application of the mechanically activated starch inhibitor according to claim 8 in mineral sorting. 10. The application according to claim 9, wherein the minerals include one or more of hematite, barite and kaolinite.

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