Method and system for regulating and controlling concentration of laterite-nickel ore high-pressure leaching ore pulp

Abstract

The invention provides a laterite-nickel ore high-pressure leaching ore pulp concentration regulation and control method and system, and belongs to the technical field of metallurgy. The laterite-nickel ore high-pressure leaching ore pulp concentration regulation and control method comprises the steps that actual concentration values and target concentration threshold values of iron ion concentration and silicon ion concentration in a circulating leaching tank are obtained; the sum of the actual concentration values of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is compared with a target concentration threshold value, and when the sum of the actual concentration values of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is larger than the target concentration threshold value, the feeding ore pulp concentration of the high-pressure reaction kettle is controlled to be reduced; therefore, the concentration of the iron ions and the concentration of the silicon ions in the ore pulp are regulated and controlled in real time, and the situation that more iron ions and silicon ions are leached in the high-pressure leaching stage, and the subsequent multi-stage countercurrent washing flocculent precipitation effect is affected is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, and in particular to a method and a control system for regulating slurry concentration in high-pressure leaching of laterite nickel ore. Background Art

[0002] At present, in the hydrometallurgical process of laterite nickel ore, after the slurry undergoes high-pressure leaching, circulating leaching and multi-stage pre-neutralization, it is necessary to use multi-stage countercurrent washing to fully wash the nickel, cobalt and manganese in the slurry underflow into the solution and perform solid-liquid separation. However, in practical applications, the flocculation and sedimentation effect of multi-stage countercurrent washing is often poor, which is not conducive to the solid-liquid separation of the solution containing nickel, cobalt and manganese and the slag.

[0003] The multi-stage countercurrent washing flocculation sedimentation effect is not good because the concentration of trivalent iron, silicon and other ions in the ore slurry is too high. The high concentration of iron, silicon and other ions is due to the high content of iron, silicon and other ions in this batch of laterite nickel ore, which leads to more iron, silicon and other ions being leached in the high-pressure leaching stage, and the flocculation sedimentation effect of multi-stage countercurrent washing is not good. Summary of the invention

[0004] The object of the present invention is to provide a method and a control system for regulating the concentration of slurry in high-pressure leaching of laterite nickel ore, which can solve the problem of poor flocculation and sedimentation effect of multi-stage countercurrent washing in the related art, and is used to realize real-time regulation of the iron ion concentration and silicon ion concentration in the slurry, thereby avoiding more iron ions and silicon ions being leached in the high-pressure leaching stage, affecting the subsequent multi-stage countercurrent washing flocculation and sedimentation effect.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a method for controlling the concentration of a laterite-nickel ore high-pressure leaching slurry, wherein the laterite-nickel ore high-pressure leaching slurry is placed in a circulating leaching tank, the feed end of the circulating leaching tank is connected to the underflow of a high-pressure reactor, and the feed end of the high-pressure reactor is connected to the underflow of a thickener, and the laterite-nickel ore high-pressure leaching slurry concentration control method comprises:

[0007] Obtaining actual concentration values ​​and target concentration thresholds of the iron ion concentration and the silicon ion concentration in the circulating leaching tank, wherein the target concentration threshold is a preset value of the sum of the iron ion concentration and the silicon ion concentration in the circulating leaching tank;

[0008] The sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is compared with the target concentration threshold value. When the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is greater than the target concentration threshold value, the feed slurry concentration of the high-pressure reactor is controlled to decrease.

[0009] In one embodiment, controlling the feed slurry concentration of the high-pressure reactor to decrease includes:

[0010] Obtaining the discharge slurry concentration and target discharge concentration value of the thickener;

[0011] The discharge slurry concentration is compared with the target discharge slurry concentration value, and when the discharge slurry concentration is equal to the target discharge slurry concentration value, the feed slurry concentration of the high-pressure reactor is controlled to stop decreasing.

[0012] In one embodiment, obtaining the discharge slurry concentration of the thickener includes:

[0013] Obtaining the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener, as well as the settling rate of floccules;

[0014] The discharge slurry concentration of the thickener is obtained based on the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener, and the settling rate of the flocculants.

[0015] In one embodiment, the discharge slurry concentration of the thickener is determined based on the following formula:

[0016]

[0017] Among them, Vmin is the sedimentation rate of flocs, C1 is the feed slurry concentration of the thickener, ρ1 is the feed slurry density of the thickener, C2 is the discharge slurry concentration of the thickener, ρ2 is the discharge slurry density of the thickener, S is the sedimentation area of ​​the thickener, and G is the discharge volume flow rate.

[0018] In one embodiment, obtaining the sedimentation rate of flocs includes:

[0019] Obtaining the initial settling velocity of the material when no flocculant is added to the thickener;

[0020] Obtaining the concentration of the flocculant in the liquid phase of the thickener, and determining the ratio between the settling velocity of the flocs and the initial settling velocity based on the concentration of the flocculant in the liquid phase;

[0021] Based on the initial sedimentation velocity and the ratio, the sedimentation rate of the flocs is determined.

[0022] In one embodiment, the ratio between the settling velocity of the flocs and the initial settling velocity is determined based on the following formula:

[0023]

[0024] Wherein, C is the concentration of the flocculant in the liquid phase of the thickener, a1, a2 and a3 are constants calibrated by experiments, and k is the ratio between the settling velocity of the flocs and the initial settling velocity.

[0025] In one embodiment, obtaining the concentration of the flocculant in the liquid phase of the thickener includes:

[0026] Obtaining the amount of flocculant added, as well as the feed slurry concentration and feed mass flow rate of the thickener;

[0027] The concentration of the flocculant in the liquid phase of the thickener is determined based on the amount of flocculant added, as well as the feed slurry concentration and feed mass flow rate of the thickener.

[0028] In one embodiment, the concentration of the flocculant in the liquid phase of the thickener is determined based on the following formula:

[0029] m=C×(1-C1)×V0

[0030] Among them, m is the amount of flocculant added, C is the concentration of flocculant in the liquid phase of the thickener, C1 is the feed slurry concentration of the thickener, and V0 is the feed mass flow rate of the thickener.

[0031] In a second aspect, the present invention provides a laterite-nickel ore high-pressure leaching slurry concentration control system, which can implement the laterite-nickel ore high-pressure leaching slurry concentration control method in any of the above schemes, and the laterite-nickel ore high-pressure leaching slurry concentration control system includes a thickener, a high-pressure reactor, a circulating leaching tank, an ion concentration collection device and an automatic control device;

[0032] The underflow of the thickener is connected to the feed end of the high-pressure reactor, and the discharge end of the high-pressure reactor is connected to the circulating leaching tank;

[0033] The ion concentration collection device is used to collect the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank, and send the actual concentration values ​​to the automatic control device;

[0034] The automatic control device is used to control the feed slurry concentration of the high-pressure reactor to decrease when the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is greater than the target concentration threshold.

[0035] In one of the embodiments, the automatic control device is also used to obtain the discharge slurry concentration of the thickener, and when the discharge slurry concentration is equal to the target discharge concentration value, the feed slurry concentration of the high-pressure reactor is controlled to stop decreasing.

[0036] The beneficial effects of the present invention are:

[0037] The method and system for controlling the concentration of laterite nickel ore high-pressure leaching pulp provided by the present invention connect the underflow of the thickener to the feed end of the high-pressure reactor, connect the discharge end of the high-pressure reactor to the circulating leaching tank, obtain the actual concentration values ​​and target concentration thresholds of the iron ion concentration and the silicon ion concentration in the circulating leaching tank, and when the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration exceeds the target concentration threshold, control the feed pulp concentration of the high-pressure reactor to decrease, thereby achieving real-time control of the iron ion concentration and the silicon ion concentration in the pulp, avoiding that more iron ions and silicon ions are leached in the high-pressure leaching stage, affecting the subsequent multi-stage countercurrent washing flocculation precipitation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A flow chart of an embodiment of a method for controlling the concentration of laterite nickel ore high pressure leaching slurry provided by the present invention;

[0039] Figure 2 A flow chart of controlling the concentration of feed slurry of a high-pressure reactor to reduce the concentration of feed slurry in a laterite nickel ore high-pressure leaching slurry provided by the present invention;

[0040] Figure 3 A flow chart of obtaining the discharge slurry concentration of a thickener in the method for controlling the slurry concentration of high-pressure leaching of laterite nickel ore provided by the present invention;

[0041] Figure 4 A flow chart of obtaining the sedimentation rate of floccules in the method for controlling the concentration of slurry in high-pressure leaching of laterite nickel ore provided by the present invention;

[0042] Figure 5 A flow chart of obtaining the concentration of the flocculant in the liquid phase of the thickener in the method for controlling the concentration of the laterite nickel ore high-pressure leaching slurry provided by the present invention;

[0043] Figure 6 The present invention provides a schematic diagram of an embodiment of a laterite nickel ore high pressure leaching slurry concentration control system.

[0044] In the figure:

[0045] 101. thickener; 102. high-pressure reactor; 103. circulating leaching tank; 104. automatic control device; 105. ion concentration collection device. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0047] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0049] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0050] like Figure 1 and Figure 6 As shown, an embodiment of the first aspect of the present invention provides a method for controlling the concentration of a laterite-nickel ore high-pressure leaching slurry. The laterite-nickel ore high-pressure leaching slurry can be contained in a circulating leaching tank 103. The feed end of the circulating leaching tank 103 is connected to the underflow of a high-pressure reactor 102. The feed end of the high-pressure reactor 102 is connected to the underflow of a thickener 101. The method for controlling the concentration of a laterite-nickel ore high-pressure leaching slurry specifically comprises the following steps:

[0051] Step S100, obtaining actual concentration values ​​and target concentration thresholds of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103, wherein the target concentration threshold is a preset value of the sum of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103;

[0052] Step S200, comparing the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 with the target concentration threshold;

[0053] Step S300: When the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 is greater than the target concentration threshold, the feed slurry concentration of the high-pressure reactor 102 is controlled to decrease.

[0054] In the laterite nickel ore high pressure leaching slurry treatment process, the laterite nickel ore slurry is initially treated by the thickener 101. After removing part of the liquid, the solid content of the slurry increases, and then enters the high pressure reactor 102. Under high temperature and high pressure conditions, metals such as nickel, cobalt, and manganese, as well as impurities such as iron and silicon in the slurry are leached. The leached slurry flows into the circulating leaching tank 103.

[0055] The core of the laterite nickel ore high-pressure leaching slurry concentration control method of this embodiment is to detect the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 in real time, and then dynamically adjust the feed slurry concentration of the high-pressure reactor 102, so as to achieve accurate control of the iron ion concentration and the silicon ion concentration in the slurry, which can effectively avoid the excessive leaching of iron ions and silicon ions during the high-pressure leaching process, thereby improving the separation effect of subsequent multi-stage countercurrent washing and flocculation precipitation. Specifically, first, the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 are obtained, that is, the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 are obtained in real time, reflecting the overall level of iron ions and silicon ions in the slurry. Then, the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 is compared with the preset target concentration threshold. The target concentration threshold is set according to the needs of the subsequent processing process, for example, multi-stage countercurrent washing and flocculation precipitation, which represents the maximum leaching amount allowed for iron ions and silicon ions in the high-pressure leaching stage. If the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 exceeds the target concentration threshold, it means that the concentration of these iron ions and silicon ions in the slurry is too high and may affect the subsequent treatment effect. Finally, the feed concentration is regulated. When the sum of the actual concentration values ​​exceeds the target concentration threshold, the regulation mechanism will be activated to reduce the feed slurry concentration of the autoclave 102. For example, this can be achieved by increasing the proportion of liquid such as water added to the autoclave 102, thereby diluting the slurry and reducing the leaching amount of iron ions and silicon ions in the high-pressure leaching stage.

[0056] In this way, the method for controlling the concentration of the slurry for high-pressure leaching of laterite nickel ore can effectively reduce the leaching of iron ions and silicon ions by timely reducing the feed slurry concentration of the high-pressure reactor 102, and reduce the influence of iron ions and silicon ions on the separation effect in the subsequent treatment process. For example, in multi-stage countercurrent washing, excessive iron ion and silicon ion concentrations may promote colloid formation and affect solid-liquid separation. Moreover, the control method ensures the stability of the ion concentration in the slurry, makes the ion concentration appropriate, helps to maintain the efficiency and stability of the entire treatment process, reduces unnecessary process adjustments, and improves production efficiency. Faced with different batches of laterite nickel ore, the iron and silicon contents may vary. The present embodiment can flexibly cope with this by adjusting the feed concentration of the high-pressure reactor 102 in real time, thereby ensuring the controllability of the ion concentration in the slurry, enhancing adaptability and flexibility, and reducing the leaching of iron ions and silicon ions. The iron ion concentration and silicon ion concentration in the slurry can be controlled in real time, thereby avoiding more iron ions and silicon ions being leached in the high-pressure leaching stage, affecting the subsequent multi-stage countercurrent washing flocculation and sedimentation effect, and solving the problem of poor flocculation and sedimentation effect of multi-stage countercurrent washing in related technologies.

[0057] like Figure 2 and Figure 6 As shown, in some embodiments, in step S300, controlling the feed slurry concentration of the high-pressure reactor 102 to decrease includes:

[0058] Step S310, obtaining the discharge slurry concentration and the target discharge concentration value of the thickener 101;

[0059] Step S320, comparing the discharge slurry concentration with the target discharge concentration value;

[0060] Step S330: When the discharge slurry concentration is equal to the target discharge slurry concentration value, the feed slurry concentration of the high-pressure reactor 102 is controlled to stop decreasing.

[0061] Among them, the discharge slurry concentration of the thickener 101 is the detected concentration value of the discharge slurry of the thickener 101, and the solid content in the slurry is detected, that is, the ratio of solid particles to the total volume of the slurry. It can be measured in real time by, but not limited to, sensors and analysis equipment integrated in the laterite nickel ore high-pressure leaching slurry concentration control system.

[0062] The target discharge concentration value is pre-set according to the requirements of the metallurgical process and the needs of subsequent processes, representing the optimal slurry concentration to improve the efficiency of the high-pressure leaching stage and optimize the subsequent flocculation and sedimentation process.

[0063] Comparing the discharge slurry concentration with the target discharge concentration value means that the automatic control device 104 and other control equipment can receive the real-time discharge slurry concentration data of the thickener 101, and compare it with the preset target discharge concentration value. The comparison is completed through the built-in algorithm and logic judgment mechanism, which ensures the accuracy and real-time performance of the slurry concentration control. The detailed steps and control structure of the two numerical comparison processing processes are similar to the prior art and will not be repeated here.

[0064] When the discharge slurry concentration is equal to the target discharge concentration value, the feed slurry concentration of the high-pressure reactor 102 is controlled to stop decreasing, which means that if the comparison result shows that the discharge slurry concentration of the thickener 101 has reached the target discharge concentration value, the automatic control device 104 and other control equipment will adjust the feed slurry concentration of the high-pressure reactor 102, that is, stop further reducing the feed slurry concentration to maintain the concentration near the target discharge concentration value.

[0065] With such a configuration, the appropriate slurry concentration ensures the efficient leaching of metals in the autoclave 102. Too high a concentration may mean that too many iron ions and silicon ions are dissolved, affecting the subsequent flocculation and precipitation effect. Too low a concentration may reduce the dissolution rate of metal ions and prolong the leaching time. By accurately controlling the discharge slurry concentration of the thickener 101, the optimal leaching conditions inside the autoclave 102 can be maintained, thereby improving the leaching efficiency and recovery rate of the metal. By controlling the feed slurry concentration of the autoclave 102 to be equal to the target discharge concentration value, the slurry concentration can be kept within an appropriate range, and the generation of too many iron ions and silicon ions in the high-pressure leaching stage can be avoided. Excessive leaching of iron ions and silicon ions will affect the solid-liquid separation effect in the subsequent flocculation and precipitation stage. Maintaining an appropriate slurry concentration helps to form a more effective floc, thereby improving the separation efficiency of metals and impurities. Real-time concentration monitoring and feedback mechanisms ensure the stability and continuity of the entire system operation, reduce fluctuations in the slurry treatment process, avoid reduced production efficiency and inconsistent product quality due to concentration fluctuations, reduce the need for manual intervention, and improve production efficiency and process controllability.

[0066] like Figure 3 and Figure 6 As shown, in some embodiments, in step S310, obtaining the discharge slurry concentration of the thickener 101 includes:

[0067] Step S311, obtaining the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener 101, and the settling rate of the flocculants;

[0068] Step S312: based on the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener 101, and the settling rate of the flocculants, the discharge slurry concentration of the thickener 101 is obtained.

[0069] Among them, the feed slurry concentration refers to the volume ratio of solid particles in the slurry, such as laterite nickel ore and water, which can be obtained in real time through online concentration measurement equipment, such as ultrasonic densitometers, X-ray densitometers, etc. The feed slurry density and the discharge slurry density, slurry density refers to the mass of slurry per unit volume, which will be affected by the ratio of solids and liquids in the slurry. Changes in density will significantly affect the fluidity, sedimentation rate and flocculation effect of the slurry.

[0070] The settling area refers to the horizontal area of ​​the slurry settling in the thickener 101, and the size of this area directly affects the speed and efficiency of the slurry settling. The discharge volume flow rate refers to the volume of slurry discharged from the discharge port of the thickener 101 per unit time, reflecting the slurry processing speed and production capacity.

[0071] As for the settling rate of flocs, flocs are the process of accelerating the settling by aggregating solid particles in the slurry into larger particles by adding flocculants. The speed of the settling rate is related to the processing efficiency of the thickener 101 and the concentration of the discharged slurry. Based on the above parameters, the discharge slurry concentration of the thickener 101 can be calculated based on the material balance and fluid dynamics principles, and the actual discharge slurry concentration of the thickener 101 can be inferred by the difference in concentration, density and flow rate between the feed and the discharge, and the influence of the floc settling rate on the slurry concentration efficiency.

[0072] With such a configuration, the slurry concentration data acquired in real time can be used to optimize the operating parameters of the thickener 101, such as the amount of flocculant added, the settling time, etc., to improve the treatment effect of the slurry in the thickener 101, thereby improving the leaching efficiency of the subsequent high-pressure reactor 102. Accurate slurry concentration information can help the automatic control device 104 adjust the feeding conditions of the high-pressure reactor 102 to avoid waste of resources caused by excessively high concentration or metal recovery rate affected by too low concentration. Precise control of slurry concentration reduces unnecessary concentration or dilution steps, saves water and energy consumption, reduces production costs, and improves the efficiency of slurry treatment and the production capacity of the production line.

[0073] like Figure 3 and Figure 6 As shown, in some embodiments, in step S312, the discharge slurry concentration of the thickener 101 is determined based on the following formula:

[0074]

[0075] Among them, Vmin is the sedimentation rate of the flocculant, which also refers to the minimum sedimentation rate of the flocculant in the thickener 101, which directly affects the concentration efficiency of the slurry and the concentration of the final discharge. C1 is the feed slurry concentration of the thickener 101, which can be the mass of solids in a unit volume of slurry. ρ1 is the feed slurry density of the thickener 101, which reflects the combined density of solids and liquids in the feed. C2 is the discharge slurry concentration of the thickener 101, which indicates the concentration of solids in the slurry after concentration. ρ2 is the discharge slurry density of the thickener 101, which is the density of the slurry after treatment, and the solid particles can be more concentrated. S is the sedimentation area of ​​the thickener 101, that is, the effective area for the sedimentation of solid particles in the slurry. G is the discharge volume flow rate.

[0076] It is understandable that the core purpose of adding flocculants is to increase the settling rate of the material. In a given thickener 101, in order to achieve the target discharge concentration and flow rate of the material, the settling rate of the floccules after adding the flocculants must satisfy the above relationship.

[0077] The formula of this embodiment can provide a quantitative calculation model between the discharge pulp concentration of the thickener 101 and the settling rate of the floccules, and can calculate the minimum settling rate of the floccules in the thickener 101. The control of this rate is conducive to keeping the discharge pulp concentration of the thickener within the target range. By adjusting the amount of flocculant added, controlling the feed pulp concentration, feed pulp density, discharge pulp density and discharge volume flow rate of the thickener, and adjusting the settling area of ​​the thickener 101, the settling rate of the floccules can be ensured to be within an appropriate range, thereby effectively controlling the concentration of the discharge pulp.

[0078] During specific operation, the automatic control device 104 can monitor the iron ion and silicon ion concentrations in the circulating leaching tank 103 through the ion concentration collection device 105. When the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration exceeds the preset target concentration threshold, the automatic control device 104 will start the control to reduce the discharge slurry concentration of the thickener 101, thereby reducing the iron and silicon ion content in the slurry entering the high-pressure reactor 102, improving the effect of the subsequent washing flocculation precipitation steps, and indirectly controlling the leaching amount of iron ions and silicon ions by adjusting the slurry concentration.

[0079] This embodiment can adjust the operating conditions of the thickener 101 in real time by monitoring Vmin and inferring C2 according to the formula to ensure that the discharge pulp concentration meets the process requirements. This embodiment has real-time control capabilities, can greatly improve the stability and efficiency of the production process, and is convenient for accurately controlling the discharge pulp concentration of the thickener 101, avoiding excessive iron ions and silicon ions from being leached during the high-pressure leaching stage, which can not only improve the effect of subsequent washing and precipitation, but also reduce the use of unnecessary chemical reagents, reduce production costs, and at the same time improve product quality and recovery rate, reduce errors in human operations, and ensure the repeatability and consistency of the process.

[0080] like Figure 4 and Figure 6 As shown, in some embodiments, in step S311, obtaining the sedimentation rate of the flocs includes:

[0081] Step 3111, obtaining the initial settling velocity of the material when no flocculant is added to the thickener 101;

[0082] Step 3112, obtaining the concentration of the flocculant in the liquid phase of the thickener 101, and determining the ratio between the settling velocity of the flocs and the initial settling velocity based on the concentration of the flocculant in the liquid phase;

[0083] Step 3113: Determine the sedimentation rate of the flocs based on the initial sedimentation velocity and the ratio.

[0084] Among them, obtaining the initial settling rate of the material when no flocculant is added to the thickener 101 means that before the flocculant is added, the particles in the slurry settle according to natural gravity to form an initial settling rate. This rate is affected by factors such as the size, density, shape of the solid particles in the slurry and the viscosity of the slurry. Obtaining this initial settling rate can be used as a benchmark for the change in settling rate after the subsequent addition of flocculants, helping to evaluate the effect of the flocculants and make necessary adjustments.

[0085] Obtaining the concentration of the flocculant in the liquid phase of the thickener 101 means that the concentration of the flocculant has a direct impact on the formation and sedimentation rate of the flocs. By monitoring the actual concentration of the flocculant in the liquid phase, it is possible to ensure that the amount of flocculant added reaches the level required to optimize the flocculation effect, avoid over-addition or under-addition, thereby improving the flocculation efficiency and saving costs.

[0086] For determining the ratio between the settling rate of flocs and the initial settling rate, after the addition of flocculants, the formation of flocs can significantly increase the settling rate of solid particles in the slurry because the flocculants help bridge and aggregate between particles, forming larger flocs, thereby increasing the settling rate. By calculating the ratio between the settling rate of flocs and the initial settling rate, the efficiency of the flocculant can be quantified, providing a basis for subsequent concentration control.

[0087] Determining the settling rate of the flocs based on the initial settling velocity and the ratio means that after obtaining the ratio of the initial settling velocity and the settling rate increased by the flocculant, the system can accurately calculate the settling rate after adding the flocculant. Since the settling rate directly affects the speed and efficiency of slurry concentration, it is beneficial to control the discharge slurry concentration of the thickener 101.

[0088] With such a configuration, this embodiment can significantly improve the concentration efficiency of the slurry in the thickener 101 by optimizing the use of flocculants, that is, a higher concentration of slurry can be obtained in the same time, which helps to improve the metal recovery rate in the subsequent high-pressure leaching stage. Accurately measuring the concentration and effect of the flocculant can help reduce unnecessary flocculant addition. By real-time monitoring and adjusting the sedimentation rate of the flocculent, the slurry concentration process can be more accurately controlled to ensure that the concentration of the discharged slurry is stable within the target discharge concentration value, and the stability and efficiency of the entire high-pressure leaching process can be maintained. Controlling the concentration of the discharged slurry can reduce the leaching of iron, silicon and other ions in the high-pressure leaching stage, avoid their interference with the subsequent washing flocculation precipitation process, and help improve the yield and product quality of the entire metallurgical process.

[0089] like Figure 4 and Figure 6 As shown, further, in step 3112, the ratio between the settling velocity of the flocs and the initial settling velocity is determined based on the following formula:

[0090]

[0091] Wherein, C is the concentration of the flocculant in the liquid phase of the thickener 101, a1, a2 and a3 are constants calibrated by experiments, reflecting the effects of the characteristics of the flocculant and the physical and chemical properties of the slurry on the settling rate, and k is the ratio between the settling rate of the flocs and the initial settling rate.

[0092] The mathematical model of this embodiment is a function based on a nonlinear relationship, which is used to quantify the effect of flocculant concentration C on the ratio k of floc settling velocity to initial settling velocity, indicating that there is a complex dependence between flocculant concentration and the enhancement ratio of settling velocity, rather than a simple linear increase or decrease.

[0093] At low concentrations, because the flocculant promotes bridging between particles, forms flocs, and improves sedimentation efficiency, the sedimentation rate Vmin of the flocs may increase significantly with the increase of the concentration C of the flocculant in the liquid phase of the thickener 101. However, as the concentration increases further, due to the weakening of the aggregation effect of the flocs, the increase in the slurry viscosity, or the influence of the flocculant itself that reduces the binding force between the particles, the growth of k will become slow, and even begin to decline after a certain point. After the values ​​calibrated by the experiment, the model can be used to predict the expected sedimentation rate enhancement ratio at different flocculant concentrations. This helps to determine the optimal use concentration of the flocculant, that is, at this concentration, the sedimentation rate of the flocs reaches the maximum value, thereby achieving the most effective pulp concentration and treatment. According to the relationship between the ratio k between the sedimentation rate of the flocs and the initial sedimentation rate and the concentration C of the flocculant in the liquid phase of the thickener 101, the amount of flocculant added can be controlled in real time to maintain the ratio k between the sedimentation rate of the flocs and the initial sedimentation rate within the optimal range. In this way, not only can the high efficiency of the flocculation process be ensured, but also the excessive use of flocculants can be avoided. By predicting the effect of changes in flocculant concentration on the sedimentation rate enhancement ratio through the above model, the possible response of the system can be predicted in advance, so that timely adjustments can be made when necessary. For example, if it is monitored that k begins to decrease, it means that the flocculant concentration may have exceeded the optimal point, and it can be adjusted by reducing the addition amount, and vice versa.

[0094] This embodiment optimizes the use of flocculants, avoids unnecessary waste, and reduces processing costs. The ratio between the settling rate of the flocculants and the initial settling rate is optimized, which directly improves the efficiency of pulp processing, reduces the residence time of the pulp in the thickener 101, and speeds up the entire high-pressure leaching process.

[0095] It can be understood that the initial sedimentation rate of the material without adding flocculant satisfies the following relationship:

[0096]

[0097] Wherein, Va is the initial settling velocity, ρ3 is the material density, ρ0 is the liquid phase density, g is the gravitational acceleration, d is the average particle size of the material, and η is the initial viscosity of the feed slurry of the thickener 101 (without flocculant).

[0098] With the addition of flocculants, the settling rate of the material changes. At this time, the settling rate of the material is proportional to the settling rate when no flocculant is added, k = Vmin / Va, Vmin is the settling rate of the flocs after adding flocculants, Va is the initial settling rate, and the k value and the flocculant concentration in the liquid phase satisfy the above relationship.

[0099] like Figure 5 and Figure 6As shown, in some embodiments, in step S3112, obtaining the concentration of the flocculant in the liquid phase of the thickener 101 includes:

[0100] Step S31121, obtaining the amount of flocculant added, and the feed slurry concentration and feed mass flow rate of the thickener 101;

[0101] Step S31122: Determine the concentration of the flocculant in the liquid phase of the thickener 101 based on the amount of flocculant added, the feed slurry concentration of the thickener 101 and the feed mass flow rate.

[0102] Among them, obtaining the amount of flocculant added refers to recording or measuring the actual amount of flocculant added, which can be achieved by precise feeding equipment such as metering pumps, ensuring the accuracy of subsequent calculations and avoiding poor coagulation effects caused by inaccurate addition amounts.

[0103] Feed slurry concentration and feed mass flow rate are key parameters that affect the distribution of flocculants in the slurry. Feed slurry concentration refers to the proportion of solid content in the slurry entering the thickener 101, while feed mass flow rate refers to the total mass of slurry entering the thickener 101 per unit time. Feed slurry concentration and feed mass flow rate are crucial for calculating the actual concentration of flocculants in the liquid phase.

[0104] The concentration of flocculant in the liquid phase of the thickener 101 is determined based on the feed slurry concentration and the feed mass flow rate of the flocculant addition. The total volume of the feed slurry can be calculated based on the feed mass flow rate and the slurry density. To determine the concentration of the flocculant in the liquid phase of the thickener 101, it is necessary to combine the amount of flocculant added with the total volume of the feed slurry, while taking into account the effect of the feed slurry concentration on the flocculant distribution, so as to determine the actual concentration of the flocculant in the liquid phase.

[0105] In this way, the present embodiment accurately obtains the concentration of the flocculant in the liquid phase to ensure that the flocculant is added at a better concentration to avoid insufficient or excessive addition. Optimized use can not only improve the flocculation effect, but also reduce the waste of flocculants and reduce production costs. Based on the real-time data of the flocculant concentration, the amount of flocculant added can be dynamically adjusted to ensure that the flocculant concentration is always maintained within the most effective range, which helps to avoid the instability of the concentration process efficiency caused by the fluctuation of the flocculant concentration. Accurate control of the flocculant concentration helps to increase the formation speed and sedimentation efficiency of the floccules, thereby accelerating the concentration process of the slurry in the thickener 101, improving the processing capacity of the thickener 101 and the overall production efficiency of the system. Reasonable flocculant concentration ensures that the solid particles in the slurry can settle in a better form, reduces suspended matter, and improves the efficiency of solid-liquid separation. It is crucial for subsequent high-pressure leaching, washing, flocculation and sedimentation processes, and helps to improve the overall metal recovery rate and product quality.

[0106] like Figure 5 and Figure 6 As shown, in some embodiments, in step S31122, the concentration of the flocculant in the liquid phase of the thickener 101 is determined based on the following formula:

[0107] m=C×(1-C1)×V0

[0108] Wherein, m is the amount of flocculant added, i.e., the mass of flocculant added to the thickener 101 per unit time. C is the concentration of flocculant in the liquid phase of the thickener 101, C1 is the feed slurry concentration of the thickener 101, which indicates the volume fraction or mass fraction of solid particles in the slurry. V0 is the feed mass flow rate of the thickener 101, which refers to the mass of slurry entering the thickener 101 per unit time.

[0109] When C1 and V0 are known and constant, the concentration C of the flocculant in the liquid phase can be controlled by adjusting the amount of flocculant added m. This formula takes into account the solid particle content C1 in the feed slurry and the total volume of the feed per unit time. The total volume of the feed per unit time is determined by V0 and C1, making the calculated concentration C of the flocculant in the liquid phase more accurate and reflecting the distribution of the flocculant in the actual liquid phase environment.

[0110] The (1-C1) part in the formula represents the volume or mass ratio of the liquid phase in the slurry. Because in the thickener 101, the slurry is composed of solid particles and liquid, and the solid particle part does not directly participate in the dissolution and distribution of the flocculant, so this part should be excluded when calculating the flocculant concentration in the liquid phase. By dividing m by (1-C1)×V0, the mass of the flocculant in the unit volume of the liquid phase is actually calculated, that is, the concentration C of the flocculant in the liquid phase.

[0111] In this way, because the concentration of the flocculant directly affects the formation speed and size of the flocs, by accurately calculating the concentration of the flocculant in the liquid phase, it can be ensured that the flocculant works at a more optimal concentration, thereby improving the flocculation efficiency and sedimentation rate of the solid particles in the slurry and accelerating the slurry concentration process. Using this formula, the required concentration of the flocculant in the liquid phase can be accurately calculated, avoiding excessive addition of flocculants, reducing flocculant waste, and reducing production costs.

[0112] Under specific feed slurry concentration and mass flow rate, adjusting the amount of flocculant added to control its concentration in the liquid phase helps maintain the stability and consistency of the entire slurry treatment process and improve the predictability and controllability of the process. By adjusting the flocculant concentration in the liquid phase of the thickener 101, the viscosity and solid content of the slurry can be optimized, creating favorable conditions for subsequent high-pressure leaching, washing and precipitation processes, and improving overall production efficiency and metal recovery.

[0113] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0114] like Figures 1 to 6 As shown, an embodiment of the second aspect of the present invention provides a laterite nickel ore high pressure leaching slurry concentration control system, which can implement the laterite nickel ore high pressure leaching slurry concentration control method in any of the above embodiments, and the laterite nickel ore high pressure leaching slurry concentration control system includes a thickener 101, a high pressure reactor 102, a circulating leaching tank 103, an ion concentration collection device 105 and an automatic control device 104, the underflow of the thickener 101 is connected to the feed end of the high pressure reactor 102, and the discharge end of the high pressure reactor 102 is connected to the circulating leaching tank 103. The ion concentration collection device 105 is used to collect the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103, and send the iron ion concentration and the silicon ion concentration to the automatic control device 104. The automatic control device 104 is used to control the feed slurry concentration of the high pressure reactor 102 to decrease when the actual concentration value of the sum of the iron ion concentration and the silicon ion concentration is greater than the target concentration threshold.

[0115] Among them, the function of the thickener 101 is to initially concentrate the laterite nickel ore pulp, remove excess water, and increase the solid content of the pulp. The underflow of the thickener 101, that is, the thicker pulp, is sent to the high-pressure reactor 102, which can improve the efficiency of high-pressure leaching, because the reduced amount of water means less energy consumption for heating and pressurization. Under high temperature and high pressure conditions, the high-pressure reactor 102 promotes the leaching of metals such as nickel, cobalt, and manganese in the pulp. The pulp concentrated by the thickener 101 enters the high-pressure reactor 102, and the pulp after the reaction is sent to the circulating leaching tank 103.

[0116] As an intermediate storage and further processing device for the ore pulp, the circulating leaching tank 103 allows the ore pulp to flow therein so as to more fully leach the metal ions therein and subsequently control the concentration. The circulating leaching tank 103 is a sampling point for the ion concentration collection device 105 to obtain the concentration of iron ions and silicon ions in the ore pulp. The ion concentration collection device 105 is responsible for real-time monitoring of the iron ion and silicon ion concentrations of the ore pulp in the circulating leaching tank 103, and can provide a basis for the automatic control device 104 to implement concentration control.

[0117] The automatic control device 104 receives the concentration information such as the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 from the ion concentration collection device 105. The automatic control device 104 can be, but is not limited to, a programmable logic controller, which receives the actual concentration value and the target concentration threshold, and sends an electrical signal to control the feed slurry concentration of the autoclave to decrease. When the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank 103 exceeds the preset target concentration value, the automatic control device 104 can send an electrical signal to the autoclave 102 to reduce the feed slurry concentration of the autoclave 102, so as to reduce the excessive generation of iron ions and silicon ions in the leaching stage.

[0118] In this embodiment, the pulp is initially concentrated by the thickener 101, which reduces the amount of water entering the autoclave 102, thereby improving the temperature and pressure conditions in the autoclave 102, which is conducive to the efficient leaching of metals. The automatic control device 104 adjusts the concentration of the pulp entering the autoclave 102 according to the concentration of iron ions and silicon ions in the circulating leaching tank 103, ensuring the optimization of the subsequent multi-stage countercurrent washing flocculation precipitation process. Excessive concentrations of iron ions and silicon ions will interfere with the formation of floccules and affect the solid-liquid separation effect of metal ions and slag. By regulating the pulp concentration, the generation of these impurity ions is reduced, the efficiency and purity of solid-liquid separation are improved, unnecessary pulp concentration regulation is reduced, and excessive iron ion and silicon ion leaching are avoided, reducing the use of chemical agents. The real-time monitoring and response of the automatic control device 104 makes the entire pulp treatment process more stable, reduces the adverse effects caused by the fluctuation of pulp composition, and improves the consistency and reliability of production. The combined use of the ion concentration collection device 105 and the automatic control device 104 enables the system to achieve automatic control, improves the intelligent level of slurry processing, reduces the need for manual intervention, and improves production efficiency. The laterite nickel ore high-pressure leaching slurry concentration control system optimizes slurry processing through the fine design and mutual cooperation of various structures, improves the metal recovery rate and product quality, and reduces production costs.

[0119] It can be understood that the laterite nickel ore high-pressure leaching slurry concentration control system provided by the present invention includes a thickener 101, a high-pressure reactor 102, a circulating leaching tank 103 and an automatic control device 104. The underflow of the thickener 101 is connected to the feed end of the high-pressure reactor 102, and the discharge end of the high-pressure reactor 102 is connected to the circulating leaching tank 103. The automatic control device 104 detects the concentration of iron ions and silicon ions in the circulating leaching tank 103 in real time through the detection module. When the sum of the concentrations of iron ions and silicon ions exceeds the set threshold, the feed slurry concentration of the high-pressure reactor 102 is controlled to be reduced, thereby realizing real-time adjustment of the iron ion concentration and the silicon ion concentration in the slurry, avoiding more iron ions and silicon ions from being leached in the high-pressure leaching stage, affecting the subsequent multi-stage countercurrent washing flocculation precipitation effect.

[0120] The detection port of the ion concentration collection device 105 can be connected to the circulating leaching tank 103 to obtain part of the slurry in the circulating leaching tank 103, and perform ion composition analysis on the part of the slurry to obtain the iron ion concentration and the silicon ion concentration. It is easy to understand that the ion concentration collection device 105 can use conventional detection equipment in the prior art and other feasible detection methods, such as metal element analyzers, spectrophotometers, plasma mass spectrometers, etc., so as to detect the iron ion concentration and silicon ion concentration in the slurry in the circulating leaching tank 103.

[0121] The feed slurry first enters the thickener 101, where the slurry is thickened based on the principle of gravity sedimentation. The bottom flow of the thickener 101 is sent to the high-pressure reactor 102 to promote the leaching of nickel, cobalt and manganese under high temperature and high pressure. Finally, the leached slurry is sent to the circulating leaching tank 103.

[0122] The core idea of ​​the present invention is to adjust the feed slurry concentration of the high-pressure reactor 102 according to the concentration of iron ions and silicon ions in the discharge of the high-pressure reactor 102 to improve the multi-stage countercurrent washing flocculation precipitation effect.

[0123] In some embodiments, the automatic control device 104 is also used to obtain the discharge slurry concentration of the thickener 101. When the discharge slurry concentration is equal to the target discharge concentration value, the feed slurry concentration of the high-pressure reactor 102 is controlled to stop decreasing. It can be understood that the feed slurry concentration of the high-pressure reactor 102 is consistent with the discharge slurry concentration of the thickener 101. When the discharge slurry concentration of the thickener 101 reaches the target concentration value, it means that the feed slurry concentration of the high-pressure reactor 102 has also reached the target concentration value.

[0124] This embodiment can improve the accuracy and real-time performance of pulp concentration control. The steps of the automatic control device 104 to obtain the discharge pulp concentration can refer to the above embodiment. The automatic control device 104 can collect the operating parameters of the thickener 101 through corresponding sensors and online analyzers, including the concentration, density, and volume flow rate of the feed pulp, the density and volume flow rate of the discharge pulp, and the sedimentation rate of the flocculants in the thickener 101. The automatic control device 104 calculates the discharge pulp concentration of the thickener 101 based on the parameters of the thickener 101. The automatic control device 104 monitors the discharge pulp concentration of the thickener 101 in real time to ensure that it matches the preset target discharge concentration value. Once the concentration reaches the target value, the control device immediately responds and stops reducing the feed pulp concentration of the autoclave 102 to maintain the stability and efficiency of the entire treatment process, which is convenient for the precise control of the discharge pulp concentration of the thickener 101 and avoids the situation where the concentration is too high or too low.

[0125] The above is a detailed introduction to the laterite nickel ore high-pressure leaching slurry concentration control system and method provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

[0126] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for controlling slurry concentration in high-pressure leaching of laterite nickel ore, characterized in that: The laterite nickel ore high pressure leaching slurry can be contained in a circulating leaching tank, the feed end of the circulating leaching tank is connected to the underflow of the high pressure reactor, the feed end of the high pressure reactor is connected to the underflow of the thickener, and the laterite nickel ore high pressure leaching slurry concentration control method comprises: Obtaining actual concentration values ​​and target concentration thresholds of the iron ion concentration and the silicon ion concentration in the circulating leaching tank, wherein the target concentration threshold is a preset value of the sum of the iron ion concentration and the silicon ion concentration in the circulating leaching tank; The sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is compared with the target concentration threshold value. When the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is greater than the target concentration threshold value, the feed slurry concentration of the high-pressure reactor is controlled to decrease.

2. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 1, characterized in that: Controlling the feed slurry concentration of the high-pressure reactor to decrease includes: Obtaining the discharge slurry concentration and target discharge concentration value of the thickener; The discharge slurry concentration is compared with the target discharge slurry concentration value, and when the discharge slurry concentration is equal to the target discharge slurry concentration value, the feed slurry concentration of the high-pressure reactor is controlled to stop decreasing.

3. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 2, characterized in that: Obtaining the discharge slurry concentration of the thickener, including: Obtaining the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener, as well as the settling rate of floccules; The discharge slurry concentration of the thickener is obtained based on the feed slurry concentration, feed slurry density, discharge slurry density, settling area and discharge volume flow rate of the thickener, and the settling rate of the flocculants.

4. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 3, characterized in that: The discharge slurry concentration of the thickener is determined based on the following formula: Among them, Vmin is the sedimentation rate of flocs, C1 is the feed slurry concentration of the thickener, ρ1 is the feed slurry density of the thickener, C2 is the discharge slurry concentration of the thickener, ρ2 is the discharge slurry density of the thickener, S is the sedimentation area of ​​the thickener, and G is the discharge volume flow rate.

5. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 3, characterized in that: Get the sedimentation rate of flocs, including: Obtaining the initial settling velocity of the material when no flocculant is added to the thickener; Obtaining the concentration of the flocculant in the liquid phase of the thickener, and determining the ratio between the settling velocity of the flocs and the initial settling velocity based on the concentration of the flocculant in the liquid phase; Based on the initial sedimentation velocity and the ratio, the sedimentation rate of the flocs is determined.

6. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 5, characterized in that: The ratio between the settling velocity of the flocs and the initial settling velocity is determined based on the following formula: Wherein, C is the concentration of the flocculant in the liquid phase of the thickener, a1, a2 and a3 are constants calibrated by experiments, and k is the ratio between the settling velocity of the flocs and the initial settling velocity.

7. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 5, characterized in that: Obtaining the concentration of the flocculant in the liquid phase of the thickener, comprising: Obtaining the amount of flocculant added, as well as the feed slurry concentration and feed mass flow rate of the thickener; The concentration of the flocculant in the liquid phase of the thickener is determined based on the amount of flocculant added, as well as the feed slurry concentration and feed mass flow rate of the thickener.

8. The method for controlling slurry concentration of laterite nickel ore high pressure leaching according to claim 7, characterized in that: The concentration of the flocculant in the liquid phase of the thickener is determined based on the following formula: m=C×(1-C1)×V0 Among them, m is the amount of flocculant added, C is the concentration of flocculant in the liquid phase of the thickener, C1 is the feed slurry concentration of the thickener, and V0 is the feed mass flow rate of the thickener.

9. A laterite nickel ore high pressure leaching slurry concentration control system, characterized in that: A method for controlling the concentration of a laterite-nickel ore high-pressure leaching slurry according to any one of claims 1 to 8 can be implemented, wherein the laterite-nickel ore high-pressure leaching slurry concentration control system comprises a thickener, a high-pressure reactor, a circulating leaching tank, an ion concentration collection device, and an automatic control device; The underflow of the thickener is connected to the feed end of the high-pressure reactor, and the discharge end of the high-pressure reactor is connected to the circulating leaching tank; The ion concentration collection device is used to collect the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank, and send the actual concentration values ​​to the automatic control device; The automatic control device is used to control the feed slurry concentration of the high-pressure reactor to decrease when the sum of the actual concentration values ​​of the iron ion concentration and the silicon ion concentration in the circulating leaching tank is greater than the target concentration threshold.

10. The laterite nickel ore high pressure leaching slurry concentration control system according to claim 9, characterized in that: The automatic control device is also used to obtain the discharge slurry concentration of the thickener, and when the discharge slurry concentration is equal to the target discharge concentration value, the feed slurry concentration of the high-pressure reactor is controlled to stop decreasing.

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