CN116287701A - A process control method for stirring and leaching of high-concentration pulp containing coarse particles - Google Patents

Abstract

The invention discloses a method for controlling the stirring and leaching process of high-concentration pulp containing coarse particles. The method comprises: leaching in segments and preset leaching time for each stage; setting control target values for different stages; configuring corresponding parameters for each stage Liquid comparison; parameter measurement; feedback the measured parameters to the control center to realize automatic addition of materials, regular parameter control and calibration of detection devices; stage leaching; after leaching, the leached pulp is separated from solid and liquid to obtain leaching slag and leaching liquid. The method adopted in the present invention can accurately control the parameters of the leaching process, can effectively increase the leaching rate of the target mineral, inhibit the leaching of impurity elements, and reduce the consumption of reagents in the leaching process.

Description

A process control method for stirring and leaching of high-concentration pulp containing coarse particles

technical field

The invention relates to the field of hydrometallurgy, in particular to a method for controlling the stirring and leaching process of high-concentration pulp containing coarse particles.

Background technique

Stirring and leaching of ore generally needs to grind the ore finely, prepare a slurry with a certain concentration, and then add acid, alkali or salt for leaching. In the acid leaching, the required acid and oxidant and other additives are generally added at one time, and the acid is added in stages during the leaching of some ores. The dissolution properties of acid-consuming minerals in ores are quite different. The acid-consuming minerals include chlorite, calcite and sericite, which will dissolve at lower acid concentrations; while pyroxene, feldspar and hematite, etc. Minerals will need higher acid below to dissolve. During acid leaching, in order to improve the utilization rate of acid and minimize the dissociation and dissolution of non-target minerals, the leaching process needs to be further optimized. Under the condition of ensuring the dissociation of the target minerals in the ore, choose coarse-grained ore for leaching as much as possible. Under normal circumstances, agitation leaching needs to grind the ore to less than 0.5mm, but in order to reduce the dissolution of impurities as much as possible, the ore particle size will be appropriately increased and the pulp concentration will be increased. In addition, reducing the acid concentration in the leaching process makes it consume more in the dissolution of target minerals, which is beneficial to control the acid consumption in the leaching process.

At present, ore leaching is mainly based on controlling the initial acid concentration or oxidation-reduction potential of the pulp. Even if acid is added in stages, the acid is added according to the initially determined amount of acid. However, in actual production, the properties of the ore are not static. Changes in the properties of the ore will cause changes in the initially determined amounts of acids and oxidants. This requires the control of the effective acid concentration and potential of the leaching process. In addition, the demand for acid used in different stages of leaching of some ores is different. Generally, high acid is required in the early stage of leaching, and low acid is required in the late stage of leaching. In the industry, precise control of process parameters is often achieved through online instruments. However, in the stirring and leaching process, the commonly used acid concentration meter is limited by the detection principle under low acid conditions (1-10g/L), and the detection accuracy decreases and the error fluctuates. Large; during the pulp leaching process, it is easy to produce secondary precipitation and coarse ore particles, which may easily cause dirt adhesion and wear on the probe. It is difficult to apply industrial online acidity meters, pH meters, and potentiometers. The content of coarse particles in the pulp increases and the concentration of the pulp increases. Increase, wear and tear intensifies, and it is even more impossible to realize automatic control operation. In the leaching process of high-concentration pulp containing coarse particles, manual sampling and measurement methods are often used, and acid and oxidant are added regularly, which causes fluctuations in key parameters such as effective acid concentration control and potential in the leaching process, affecting the leaching of target minerals, and the operation is cumbersome.

Contents of the invention

Aiming at the problems such as difficult automatic control of acid concentration, potential and related ion concentration control in the stirring and leaching process of high-concentration pulp containing coarse particles, and cumbersome operation, the present invention provides a process control method for stirring and leaching of high-concentration pulp containing coarse particles, which realizes The acidity control of the slurry leaching process in this system improves the control accuracy of the effective acid in the leaching process.

A process control method for stirring and leaching of high-concentration pulp containing coarse particles, comprising:

S1: Divide the stirring leaching process into multiple stages, and preset the leaching time of each stage;

Specifically, the agitation leaching process is divided into N stages according to the ore type and ore leaching condition test, namely the first stage, the second stage, ..., the Nth stage, wherein N is a natural integer; and predict Set the leaching time of each stage. When the leaching time of the current stage reaches the preset leaching time, it will automatically switch to the next stage of ore leaching until the ore leaching of all stages is completed.

S2: Preset the corresponding control target value for the key parameters that need to be controlled at each stage;

Specifically, the key parameters that need to be controlled in each stage of leaching ore are different. Therefore, the key parameters of each stage are determined through conditional tests, and the control target values corresponding to the key parameters are preset.

S3: Prepare the corresponding reference solution according to the control target value of each stage; the reference solution is used to correct the deviation of the detector during the stirring process, improve the accuracy of the measurement parameters, and realize the precise control of the parameters of the leaching process.

S4: Insert the detector into the slurry being stirred and leached at preset intervals to measure key parameters;

Specifically, the ore is mixed into pulp, stirred and leached, and an online detector is inserted at a preset interval to measure key parameters in the pulp.

S5: Feedback the measured key parameters to the control center for comparison with the preset control target value, and the control center controls the amount of reagent added according to the comparison result until the deviation between the measured value of the detector and the control target value is less than the preset value;

S6: Clean the measuring meter and transfer it to the reference solution for deviation detection: when the preset conditions are met, the measuring meter will continue to be used; otherwise, the measuring meter will be replaced, activated or calibrated before returning to use;

Specifically, when the S5 process is over, the probe of the online detector inserted into the pulp is automatically lifted, automatically cleaned and transferred to the reference solution matched at the current stage, and the deviation of the detector is detected: if the preset conditions are met, it indicates that the detection The meter can continue to be used; if the preset conditions are not met, it means that the detector is damaged by corrosion or absorbs more substances during the detection process, which affects the detection accuracy, and the detector needs to be replaced, activated or calibrated before returning to use.

S7: Judging whether the leaching time of the current stage reaches the preset leaching time:

If yes, judge whether ore leaching of all stages is completed: if satisfied, enter S8; if not, adjust to the next stage of leaching, and return to S4;

If not, return to S4;

S8: performing solid-liquid separation on the leached pulp.

Further, the multiple stages in S1 are determined in combination with the type of ore to be leached and the ore leaching conditions.

Further, the key parameters are determined according to the ore leaching chamber condition test.

Further, the range of the preset interval in S4 is 5min-10h.

Further, the key parameters include at least one of acid concentration, pH, potential or related ion concentration to be controlled during the leaching process.

Further, the specific process for the control center to control the reagents according to the comparison results is:

When the measured key parameter is lower than the control target value, start to add reagents until the deviation between the measured value of the detector and the control target value is less than the preset value.

Further, the preset condition in S6 is specifically: the difference between the key parameters obtained by the detector measuring the reference solution and the actual value of the reference solution is smaller than the preset value.

Further, the method of solid-liquid separation in S8 includes: multi-stage countercurrent decantation or vacuum filtration.

Further, the method for controlling the agitated leaching process of the high-concentration pulp containing coarse particles as described above is applied to the process control of single tank leaching, multi-stage continuous leaching process or multi-stage countercurrent leaching process control.

Beneficial effect

The present invention proposes a method for controlling the stirring and leaching process of high-concentration ore pulp containing coarse particles. The method divides the stirring process into multiple stages, realizes precise control in stages, and improves the control accuracy of effective acid in the leaching process; the method also The corresponding reference solution is set based on multiple stages to realize timely correction of the deviation of the detector, solve the problem that the detector is damaged by corrosion or absorb more substances during the detection process, and improve the detection accuracy during the stirring process.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic flowchart of a process control method for stirring and leaching of high-concentration pulp containing coarse particles provided by an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other implementations obtained by persons of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

As shown in Figure 1, the present invention provides a process control method for agitation and leaching of high-concentration pulp containing coarse particles, including:

S1: The stirring leaching process is divided into multiple stages, and the leaching time of each stage is preset; among them, multiple stages are determined by combining the type of ore to be leached and the ore leaching condition test.

S2: Preset corresponding control target values for the key parameters that need to be controlled at each stage; among them, the key parameters are determined according to the ore leaching indoor condition test, including the acid concentration, pH, potential or related parameters that need to be controlled during the leaching process. at least one of ion concentrations.

S3: Prepare the corresponding reference solution according to the control target value of each stage.

S4: Insert the detector into the pulp being stirred and leached at preset intervals to measure key parameters; the preset interval ranges from 5min to 10h, and the actual interval depends on the type of different ores. During specific implementation, the preset interval time inserted by the detector can be adjusted within the range of the preset interval time.

S5: Feedback the measured key parameters to the control center for comparison with the preset control target value, and the control center controls the amount of reagent added according to the comparison result until the deviation between the measured value of the detector and the control target value is less than the preset value; In a feasible embodiment, the preset value can be adjusted according to actual needs, and is not limited thereto.

S6: Clean the measuring meter and transfer it to the reference solution for deviation detection: when the preset conditions are met, the measuring meter will continue to be used; otherwise, the measuring meter will be replaced, activated or calibrated before returning to use;

S7: Judging whether the leaching time of the current stage has reached the preset leaching time: (1) If yes, judging whether the ore leaching of all stages is completed: if satisfied, enter S8; if not, adjust to the next stage of leaching and return S4; (2) If not, return to S4;

S8: performing solid-liquid separation on the leached pulp. Among them, the way of solid-liquid separation includes: multistage countercurrent decantation or vacuum filtration.

The above-mentioned leaching control process can be applied to single-tank leaching process control, and can also be used for multi-stage continuous leaching process control and multi-stage countercurrent leaching process control. A detailed description is given below through specific examples.

Example 1

A certain uranium ore has a uranium grade of 0.036%, 80% of which are broken to -2mm, and a pulp concentration of 73%. The stirring and leaching control process is as follows:

(1) Segmentation of leaching: the leaching process is controlled in three stages, and the leaching time of each stage is set. In actual implementation, the leaching time of each stage can be adjusted according to actual needs. In this embodiment, the leaching time of each stage is set for 3h.

(2) Set the control target value: the key parameters to be controlled in each stage are pH and potential; set the first stage leaching control target value: pH is 1.0, potential 490mV, the second stage leaching control target value: pH is 1.2, The potential is 490mV, and the target value of the third stage leaching: pH is 1.6, and the potential is 480mV.

(3) Configure the reference solution: prepare the reference solution according to the pH and potential required for the first stage, the second stage, and the third stage of stirring leaching; wherein, the corresponding reference solution #1 of the first stage: the pH is 1.0, the potential is 490mV, the corresponding reference solution #2 in the second stage: pH is 1.2, the potential is 490mV, the corresponding reference solution #3 in the third stage: pH is 1.6, the potential is 480mV. The above-mentioned reference solution is used to correct the parameters measured by the electrode in each process stage.

(4) Parameter measurement: Insert an online pH meter and a potentiometer into the pulp leached by stirring every 15 minutes to measure the pH value and potential value. The initial values measured in the first stage of this embodiment: pH is 5.35 and potential is 370mV.

(5) Parameter feedback and control: Feedback the pH value and potential value measured in (4) to the control center, and compare them with the control target value. When the measured value measured by the detector is lower than the control target value, the program controls the acid addition , Oxidant, the deviation between the measured value of pH and the control target value is less than 0.1, and the deviation between the measured value of potential and the control target value is less than 10mV.

(6) Calibration of the tester: When the (5) process is over, the inserted online instrument probe is automatically lifted, automatically cleaned and then transferred to reference solution #1, and the measured value obtained by the tester to measure the reference solution and the actual value of the reference solution If the deviation is less than the preset value, the online instrument probe can continue to be used, realizing regular parameter control and detection device calibration. During specific implementation, the preset value of the deviation can be adjusted according to actual needs. In this embodiment, the preset value of the deviation is 5%.

(7) Stage leaching: the first stage leaching process can repeat the above-mentioned steps of measuring with a detector and adding reagents 12 times. When the first-stage leaching time reaches 3 hours, the program automatically starts the second-stage leaching. When the measured value measured by the detector is lower than the control target value, the reagent is automatically added to make the deviation between the measured value and the control target value less than 5%. The third stage of leaching is the same as the first two stages of leaching except that the control target values of key parameters are different from those of the first two stages.

(8) Solid-liquid separation of ore pulp: After the three stages of ore leaching are completed, the leached ore pulp is separated from slag and leachate by multi-vacuum filtration, and each control index in the leachate is measured.

After the coarse-grained high-concentration pulp is leached by the above steps, the uranium leaching rate is 89.5% (the one-time acid leaching rate is 81.2%), the pH of the leaching solution is 1.65, and the potential is 475mV. By the control method of the present invention, the condition of equal acid consumption Under this condition, the leaching rate of the target element is effectively improved.

Example 2:

A certain vanadium ore has a vanadium grade of 0.96%, 96% of which are broken to -1mm, and a pulp concentration of 60%. The stirring and leaching control process is as follows:

(1) Segmentation of leaching: the leaching process is controlled in two stages, and the leaching time of each stage is set. During specific implementation, the leaching time of each stage can be adjusted according to actual needs. In this embodiment, the leaching time of the first stage is 2h, the second stage leaching time is 5h.

(2) Set control target value: the key parameters to be controlled in the first stage are pH and Na ⁺ , and the key parameters to be controlled in the second stage are acid concentration; set the leaching control target value in the first stage: pH is 1.6, The Na ⁺ concentration is 0.2g/L, and the second stage leaching control target value: the acid concentration is 25g/L.

(3) Configure reference solution: according to the acid solution, pH reference solution, and sodium sulfate solution required for different stages of agitation and leaching; the corresponding reference solution #1 in the first stage: pH is 1.6, Na ⁺ concentration is 0.2g /L, the corresponding reference solution #2 in the second stage: the acid concentration is 25g/L.

(4) Parameter measurement: the first stage leaching: the crushed ore is added to the existing second stage leachate to prepare a slurry with a mass fraction of 60%, and the temperature is raised to 90°C for stirring and leaching, and an online pH meter is inserted every 30 minutes. Na ⁺ concentration meter, in the present embodiment, the initial values measured by the detector are pH 0.72, 0.03g/L.

(5) Parameter feedback and control: Feedback the pH value and Na ⁺ ion concentration measured in (4) to the control center, and compare with the control target value. When the measured value measured by the detector is lower than the control target value, the program control Add acid, sodium sulfate solution.

(6) Calibration of the detector: When the (5) process is over, the inserted online meter probe is automatically lifted, automatically cleaned and then transferred to 1# reference solution, and the measured value obtained by the detector measuring the reference solution is the same as the actual value of the reference solution If the deviation is less than the preset value, the online instrument probe will continue to be used to achieve regular parameter control and detection device calibration. During specific implementation, the preset value of the deviation can be adjusted according to actual needs. In this embodiment, the preset value of the deviation is 3%.

(7) Stage leaching: the first stage leaching process can repeat the above-mentioned steps of measuring and adding reagents 4 times. When the first-stage leaching time reaches 2 hours, the program automatically starts the second-stage leaching. When the measured value measured by the detector is lower than the control target value, the reagent is automatically added to make the deviation between the measured value and the control target value less than 3%.

(7) Solid-liquid separation of ore pulp: After the three stages of ore leaching are completed, the leached ore pulp is separated from slag and leachate by means of multi-vacuum filtration. .

After the coarse-grained high-concentration pulp is leached by the above steps, the leaching rate of vanadium is 75.3%. Sodium sulfate is added in the first stage of leaching to convert the leached ferric iron into ferrite precipitation, thereby inhibiting its leaching. Therefore, the trivalent iron in the first stage of leachate The iron concentration was reduced to below 0.5g/L; the final pH of the first-stage leaching solution was 1.65, and the Na ⁺ concentration was 0.19g/L. Through the control method of the invention, the dissolution of impurity elements is effectively controlled by improving the control precision.

Through the method adopted in the present invention, the parameters of the leaching process can be accurately controlled, the leaching rate of the target mineral can be effectively improved, and the reagent consumption in the leaching process can be reduced. The difference between the acid concentration and the set value is less than 1g/L, and the difference between the pH and the set value is less than 0.1, the difference between the potential and the set value is less than 10mV, and the concentration of other ions is less than 0.2g/L from the set value.

It can be understood that, the same or similar parts in the above embodiments can be referred to each other, and the content that is not described in detail in some embodiments can be referred to the same or similar content in other embodiments.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (9)

1. A process control method for stirring and leaching of high-concentration pulp containing coarse particles, characterized in that it comprises: S1: Divide the stirring leaching process into multiple stages, and preset the leaching time of each stage; S2: Preset the corresponding control target value for the key parameters that need to be controlled at each stage; S3: Prepare corresponding reference solution according to the control target value of each stage; S4: Insert the detector into the slurry being stirred and leached at preset intervals to measure key parameters; S5: Feedback the measured key parameters to the control center for comparison with the preset control target value, and the control center controls the amount of reagent added according to the comparison result until the deviation between the measured value of the detector and the control target value is less than the preset value; S6: Clean the measuring meter and transfer it to the reference solution for deviation detection: when the preset conditions are met, the measuring meter will continue to be used; otherwise, the measuring meter will be replaced, activated or calibrated before returning to use; S7: Judging whether the leaching time of the current stage reaches the preset leaching time: If so, judge whether ore leaching of all stages is completed: if satisfied, enter S8; if not, adjust to the next stage of leaching, and return to S4; If not, return to S4; S8: performing solid-liquid separation on the leached pulp. 2. The method for controlling the stirring and leaching process of high-concentration pulp containing coarse particles according to claim 1, characterized in that the multiple stages in S1 are determined in combination with the type of ore to be leached and the ore leaching conditions. 3. The method for controlling the stirring and leaching process of high-concentration ore pulp containing coarse particles according to claim 1, wherein the key parameters are determined according to the ore leaching laboratory condition test. 4. The method for controlling the stirring and leaching process of high-concentration pulp containing coarse particles according to claim 1, characterized in that the range of the preset interval time in S4 is 5min-10h. 5. The method for controlling the stirring and leaching process of high-concentration ore pulp containing coarse particles according to claim 1, wherein the key parameters include at least one of acid concentration, pH, potential or related ion concentrations that need to be controlled in the leaching process one. 6. The method for controlling the stirring and leaching process of high-concentration ore pulp containing coarse particles according to claim 1, characterized in that, the specific process for the control center to control the reagents according to the comparison results is: When the measured key parameter is lower than the control target value, start to add reagents until the deviation between the measured value of the detector and the control target value is less than the preset value. 7. The method for controlling the stirring and leaching process of high-concentration ore pulp containing coarse particles according to claim 1, wherein the preset condition in S6 is specifically: the key parameters obtained by measuring the reference liquid and the reference liquid The actual value deviation is smaller than the preset value. 8. The process control method for stirring and leaching of high-concentration pulp containing coarse particles according to claim 1, characterized in that the method of solid-liquid separation in S8 includes: multi-stage countercurrent decantation or vacuum filtration. 9. The process control method for stirring and leaching process of high-concentration pulp containing coarse particles according to any one of claims 1-8 is applied to single-tank leaching process control, multi-stage continuous leaching process control or multi-stage countercurrent leaching process control.

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