A pre-desilication system and method
By integrating the thermal energy of the leaching device into alumina production, the problem of dependence on external heat sources for independent pre-desiliconization systems has been solved, achieving efficient recycling of waste heat, reducing energy consumption and improving production efficiency.
Patent Information
- Application Number
- CN202610365943.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-24
- Publication Date
- 2026-06-16
AI Technical Summary
Existing independent pre-desiliconization systems rely on external fresh steam or electricity supply in alumina production, failing to effectively utilize the waste heat resources in the original production line, resulting in increased energy consumption and higher production costs.
The heating process of the preparation solution is integrated into the leaching device, and the heat is supplied to the slurry grinding device through a conveying device, so as to realize the efficient recycling of the system's waste heat and reduce the dependence on external heat sources.
By utilizing the thermal energy of the integrated leaching device, the external energy consumption of the traditional independent pre-desiliconization process is reduced, thereby improving production efficiency and reducing energy consumption.
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Figure CN122212196A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of alumina production technology, and in particular to a pre-desiliconization system and method. Background Technology
[0002] In the Bayer process of alumina production, in order to process bauxite with high aluminum-silicon ratio and low active silicon, the existing technology usually adopts the solution of adding an independent pre-desiliconization system. This requires the construction of a dedicated pre-desiliconization tank system outside the main production line to separately heat-insulate the ground raw ore slurry.
[0003] Specifically, the working principle of the independent pre-desilicon system is to transport the slurry to a dedicated pre-desilicon tank and keep it at a temperature close to the boiling point for a long time, so as to promote the pre-reaction of the less reactive silicon minerals in the ore with the conditioning liquid, generating sodium silicate slag that is easy to separate, thereby improving the subsequent settling and leaching performance of the slurry.
[0004] However, although the aforementioned independent pre-desiliconization system can improve the desiliconization effect to some extent, the large amount of heat energy required for the operation of the pre-desiliconization system depends entirely on external fresh steam or electricity supply, and fails to utilize the waste heat resources in the original production line, resulting in a significant increase in production energy consumption and pushing up the overall production cost of alumina. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a pre-desilicon system and method to solve the technical problem that although the existing independent pre-desilicon system can improve the desilicon effect to a certain extent, the large amount of heat energy required for the operation of the pre-desilicon system depends entirely on the external fresh steam or electricity supply, and fails to utilize the waste heat resources in the original production line, resulting in a significant increase in production operation energy consumption and pushing up the overall production cost of alumina.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a pre-desiliconization system, comprising: a slurry grinding device; a pre-desiliconization device connected to the slurry grinding device; a leaching device including a first leaching unit and a second leaching unit, the first leaching unit being connected to the pre-desiliconization device; an evaporation device connected to the second leaching unit; and a conveying device connected to the second leaching unit and the slurry grinding device; wherein the evaporation device is used to produce a blending solution; the second leaching unit is used to heat the blending solution from the evaporation device; the conveying device is used to convey the blending solution from the second leaching unit to the slurry grinding device; and the pre-desiliconization device is used to receive the slurry from the slurry grinding device and perform a pre-desiliconization reaction.
[0007] In some embodiments, the pre-desilicon device includes a pre-desilicon tank connected to the slurry grinding device and the first leaching unit.
[0008] In some embodiments, multiple pre-desilicon tanks are provided, and the multiple pre-desilicon tanks are connected in series between the slurry grinding device and the first leaching unit.
[0009] In some embodiments, the pre-desilicon apparatus further includes a slurry tank connected between the pre-desilicon tank and the first leaching unit.
[0010] In some embodiments, the pre-desilicon device further includes a transfer pump disposed between the pre-desilicon tank and the slurry tank, the transfer pump being used to pump the slurry in the pre-desilicon tank to the slurry tank.
[0011] In some embodiments, the conveying device is also connected to the slurry tank, and the conveying device is also used to convey the preparation liquid of the second leaching unit to the slurry tank.
[0012] In some embodiments, the conveying device includes a first pipe, a second pipe, and a three-way valve, the three-way valve being connected to the second leaching unit, the first pipe, and the second pipe, the first pipe being connected to the slurry grinding device, and the second pipe being connected to the slurry tank.
[0013] In some embodiments, the pre-desiliconization system further includes a solids concentration sensor disposed within the slurry tank; and / or, the pre-desiliconization system further includes a temperature sensor disposed within the slurry grinding apparatus and / or the slurry tank.
[0014] In some embodiments, the dissolution device is a tubular reactor, and the first dissolution unit and the second dissolution unit are continuous pipes in different sections of the tubular reactor.
[0015] In a second aspect, the present invention provides a pre-desilicon removal method, applied to the pre-desilicon removal system described in the first aspect, comprising: The prepared liquid produced by the evaporation device is transported to the second dissolution unit for heat exchange. The preparation solution in the second leaching unit is transported to the slurry grinding device, and the heat-exchanged preparation solution is used to grind the ore in the slurry grinding device. The slurry in the slurry grinding device is transported to the pre-desiliconization device for pre-desiliconization operation; The slurry in the pre-desilicon tank is transported to the first leaching unit for heating and leaching reaction.
[0016] The pre-desiliconization system of the present invention integrates the heating process of the preparation liquid into the leaching device and uses its heat to provide a heat source for the grinding of the slurry before pre-desiliconization, thereby realizing the efficient recycling of the system's waste heat and significantly reducing the external energy consumption of the traditional independent pre-desiliconization process.
[0017] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are described in detail below. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the pre-desilicon removal system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the pre-desilicon device in the pre-desilicon system of an embodiment of the present invention.
[0019] Explanation of reference numerals in the attached figures: 10. Slurry grinding device; 20. Pre-desiliconization device; 21. Pre-desiliconization tank; 22. Slurry tank; 30. Leaching device; 31. First leaching unit; 32. Second leaching unit; 40. Conveying device; 50. Evaporation device. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0024] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0026] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0027] Please see Figure 1This invention provides a pre-desiliconization system, comprising: a slurry grinding device 10; a pre-desiliconization device 20 connected to the slurry grinding device 10; a leaching device 30, including a first leaching unit 31 and a second leaching unit 32, the first leaching unit 31 being connected to the pre-desiliconization device 20; an evaporation device 50 connected to the second leaching unit 32; and a conveying device 40 connected to the second leaching unit 32 and the slurry grinding device 10; wherein the evaporation device 50 is used to produce a blending solution; the second leaching unit 32 is used to heat the blending solution from the evaporation device 50; the conveying device 40 is used to convey the blending solution from the second leaching unit 32 to the slurry grinding device 10; and the pre-desiliconization device 20 is used to receive the slurry from the slurry grinding device 10 and perform a pre-desiliconization reaction.
[0028] For example, the slurry grinding device 10 refers to equipment used in the alumina production process to mix bauxite with a liquid medium (such as a blending solution) and perform preliminary grinding. It is used to crush and disperse the solid particles of bauxite in the liquid phase to form a slurry with a certain solid content and fineness, so as to provide qualified slurry for subsequent processing steps.
[0029] For example, the leaching device 30 refers to the reaction equipment in alumina production. It can be a tubular reactor used to chemically react alumina in the slurry with an alkaline solution under high temperature and high pressure conditions, thereby leaching it into the solution. In this embodiment, the leaching device 30 is structurally and / or functionally divided into a first leaching unit 31 and a second leaching unit 32. The first leaching unit 31 is used to perform the main leaching reaction, while the second leaching unit 32 is configured to heat the preparation solution. For example, a waste heat recovery unit is provided between the first leaching unit 31 and the second leaching unit 32. The waste heat recovery unit is essentially a highly efficient heat exchange section integrated inside the leaching device 30. Specifically, the high-temperature slurry discharged from the end of the first leaching unit 31 flows through the waste heat recovery unit and undergoes indirect heat exchange with the preparation solution flowing through the second leaching unit 32, thereby recovering heat. This waste heat recovery unit, which preheats the feed medium with the waste heat of the slurry within the leaching device 30, is a common design in existing alumina production lines and will not be elaborated upon here.
[0030] For example, evaporation device 50 refers to the equipment group involved in the mother liquor evaporation process in the alumina production process, such as a multi-effect evaporator, which is used to heat and evaporate the low-concentration mother liquor returned from the production cycle to remove excess water, thereby producing a blended solution that meets the concentration requirements of the leaching process.
[0031] For example, the pre-desiliconization device 20 refers to a combination of equipment for pre-desiliconizing slurry, which receives slurry from slurry grinding device 10 and keeps it at an appropriate temperature for a sufficient time to cause the less active silica-containing minerals in the slurry to react with alkali in advance to form sodium silicate slag, thereby improving the subsequent settling and leaching performance of the slurry.
[0032] For example, the conveying device 40 refers to a combination of pipelines, pumps and control valves used to connect different units of the system and convey liquid materials. It includes a fluid channel from the second leaching unit 32 to the slurry grinding device 10, which stably and controllably conveys the high-temperature blended liquid heated by the second leaching unit 32 to the slurry grinding device 10 to achieve the transfer of heat energy and materials.
[0033] It should be noted that the alumina production line equipped with slurry grinding device 10, leaching device 30 and evaporation device 50 is an existing mature production system and falls within the scope of existing technology.
[0034] It is understood that the main improvement of this embodiment compared to the prior art lies in the functional division of the existing leaching device 30 into a first leaching unit 31 and a second leaching unit 32, and the addition of a pre-desiliconization device 20 in the process flow between the first leaching unit 31 and the slurry grinding device 10. The first leaching unit 31 is mainly used to process the slurry that has undergone pre-desiliconization, completing the final leaching reaction; the second leaching unit 32 is used to heat the low-temperature preparation liquid from the evaporation device 50, raising its temperature; and the newly added conveying device 40 guides the high-temperature preparation liquid output from the second leaching unit 32 to the slurry grinding device 10. Therefore, in this embodiment, the heating process of the preparation liquid, which originally required external heat source preheating, is integrated into the heat energy utilization stage of the leaching device 30. This heat is then precisely supplied to the initial stage of slurry grinding via the conveying device 40, providing a more favorable initial slurry temperature for the subsequent pre-desiliconization reaction. Furthermore, the heat energy inside the leaching device 30 is effectively recovered and utilized, reducing the need for an independent external heat source. This achieves the goal of reducing the overall energy consumption of the system while integrating the pre-desiliconization function.
[0035] Please see Figure 2 In some embodiments, the pre-desilicon device 20 includes a pre-desilicon tank 21, which is connected to the slurry grinding device 10 and the first leaching unit 31.
[0036] For example, the pre-desilicon tank 21 is an atmospheric pressure reaction vessel with insulation facilities, which is used to receive and store slurry from the slurry grinding device 10 and maintain the slurry at a set temperature for a sufficient time to complete the pre-desilicon reaction.
[0037] In some embodiments, multiple pre-desilicon tanks 21 are provided, and the multiple pre-desilicon tanks 21 are connected in series between the slurry grinding device 10 and the first leaching unit 31.
[0038] For example, multiple pre-desilicon tanks 21 are connected sequentially via pipes to form a series material flow path. The slurry enters from the inlet of the first pre-desilicon tank 21, flows through all the series-connected pre-desilicon tanks 21 in sequence, and finally exits from the outlet of the last pre-desilicon tank 21. This increases the effective reaction volume of the slurry within the pre-desilicon unit 20 to meet the slurry residence time required by the process.
[0039] For example, the pre-desiliconization unit 20 also includes a conveying mechanism disposed between adjacent pre-desiliconization tanks 21 for conveying the slurry in the adjacent pre-desiliconization tanks 21 toward the first leaching unit 31. For example, the conveying mechanism can be a pneumatic extraction device that uses the power generated by compressed air to lift and convey the slurry in the preceding pre-desiliconization tank 21 to the following pre-desiliconization tank 21, realizing non-mechanical pumping transfer of materials between the pre-desiliconization tanks 21. For example, the conveying mechanism can also be a mechanical stirring conveying device 40 or other equivalent mechanism that enables directional flow of the slurry between the pre-desiliconization tanks 21; the specific form can be selected according to the process layout and energy consumption requirements, and will not be elaborated here.
[0040] Understandably, multiple pre-desilicon tanks 21 connected in series together constitute a pre-desilicon reaction zone with a total volume meeting process requirements. The slurry flows sequentially through each pre-desilicon tank 21, ensuring that its total residence time within the pre-desilicon unit 20 meets process requirements, such as 10-14 hours, providing the necessary conditions for the sufficient reaction between the less reactive silicon minerals and the alkaline solution. During this process, the silicon minerals gradually transform into a sodium-silicon slag solid phase that is easily separated in subsequent processes, thereby significantly reducing the silicon content in the slurry liquid phase, achieving the goal of improving slurry settling performance and enhancing the quality of the final product.
[0041] In some embodiments, the pre-desilicon device 20 further includes a slurry tank 22, which is connected between the pre-desilicon tank 21 and the first leaching unit 31.
[0042] For example, slurry tank 22 is an intermediate container for mixing, storing, and blending slurry, which receives slurry from pre-desiliconization tank 21 that has undergone pre-desiliconization. For example, the slurry in slurry tank 22 can be mixed with high-temperature blending liquid from other parts of the pre-desiliconization system to achieve final adjustment of slurry composition and precise temperature control.
[0043] In some embodiments, the pre-desilicon device 20 further includes a transfer pump, which is disposed between the pre-desilicon tank 21 and the slurry tank 22. The transfer pump is used to pump the slurry in the pre-desilicon tank 21 to the slurry tank 22.
[0044] For example, the transfer pump is a positive displacement or centrifugal pump used to transport high solids content slurry. It uses mechanical power to stably and continuously transport the slurry that has been reacted in the pre-desilicon tank 21 to the downstream slurry tank 22, ensuring the smooth flow of materials between processes.
[0045] In some embodiments, the conveying device 40 is also connected to the slurry tank 22, and the conveying device 40 is also used to convey the preparation liquid of the second dissolution unit 32 to the slurry tank 22.
[0046] It should be explained that, due to the prolonged heat treatment in the pre-desilicon tank 21 of the pre-desilicon unit 20, the slurry may have a higher solid content and deviate from the optimal leaching range when it reaches the slurry tank 22. To meet the strict requirements of the first leaching unit 31 for the temperature and chemical composition of the feed slurry, final adjustment is required in the slurry tank 22. Based on this, the conveying device 40 transports the high-temperature prepared liquid from the second leaching unit 32 to the slurry tank 22, mixing it with the slurry from the pre-desilicon tank 21 to dilute the slurry. This adjusts the solid content and aluminum and alkali concentrations of the slurry in the slurry tank 22 to within the acceptable range required by the leaching process. Furthermore, it increases the temperature of the slurry entering the first leaching unit 31, bringing it to the ideal leaching feed temperature, reducing or even eliminating the energy consumption for additional heating of the slurry, and ensuring that the leaching reaction can proceed efficiently under the required process conditions.
[0047] In some embodiments, the conveying device 40 includes a first pipe, a second pipe, and a three-way valve. The three-way valve is connected to the second leaching unit 32, the first pipe, and the second pipe. The first pipe is connected to the slurry grinding device 10, and the second pipe is connected to the slurry tank 22.
[0048] In some embodiments, the pre-desilicon system further includes a solid concentration sensor disposed within the slurry tank 22; and / or, the pre-desilicon system further includes a temperature sensor disposed within the slurry grinding device 10 and / or within the slurry tank 22.
[0049] For example, a solids concentration sensor is a device used to detect the mass percentage of solid particles in a slurry. It is installed in the slurry tank 22 to continuously monitor the solids content of the mixed slurry and provide feedback signals for automatically controlling the flow rate of the added conditioning liquid. This ensures that the solids content of the slurry entering the first leaching unit 31 is stable within the optimal range required by the process, thus guaranteeing the uniformity and efficiency of the leaching reaction.
[0050] For example, a temperature sensor is a device for measuring the temperature of the medium. It is installed in the slurry grinding device 10 and can be used to monitor the temperature of the initial slurry after grinding in order to evaluate the preheating effect of the hot-mixed liquid on the grinding. It is installed in the slurry tank 22 and is used to monitor the temperature of the final mixed slurry to ensure that it reaches the feed temperature required to enter the first leaching unit 31.
[0051] In some embodiments, the dissolution device 30 is a tubular reactor, and the first dissolution unit 31 and the second dissolution unit 32 are continuous pipes in different sections of the tubular reactor.
[0052] For example, the tubular reactor is a continuous pipeline system composed of multiple, multi-layered sleeves connected sequentially. In this embodiment, the first leaching unit 31 is defined as the continuous pipeline in the tubular reactor mainly used to complete the final high-temperature leaching chemical reaction, and the second leaching unit 32 is defined as the continuous pipeline located upstream of the first leaching unit 31, mainly used to recover waste heat from the tubular reactor. The main medium flowing through the tubes of the second leaching unit 32 is the conditioning liquid, whose heat comes from the waste heat of the high-temperature leaching slurry at the outlet of the first leaching unit 31; while the slurry flowing through the first leaching unit 31 is a preheated and pre-desiliconized mineral slurry, which is ultimately heated to the reaction temperature by an external heat source.
[0053] In one feasible implementation, the blending solution (temperature approximately 70°C) from the evaporator 50 is pumped into the second leaching unit 32, where the residual heat of the leaching slurry is used to preheat the blending solution to approximately 98°C. The preheated hot blending solution is then split, with one stream being sent to the slurry grinding unit 10 for mixing and grinding with bauxite to obtain an initial slurry with a solid content of approximately 400 g / L and a temperature of approximately 85°C. This initial slurry enters a series of pre-desiliconizing tanks 21, where it undergoes a pre-desiliconizing reaction under normal pressure for a total residence time of approximately 12 hours to complete the pre-desiliconization. After the pre-desiliconization reaction in the pre-desiliconizing tanks 21, the slurry temperature drops to approximately 83°C and is pumped to the slurry tank 22, where it is mixed with the other preheated hot blending solution to raise the slurry temperature to approximately 90°C and perform final composition adjustments. The final blended slurry is then pumped into the first leaching unit 31 to complete the final heating and leaching reaction.
[0054] This invention provides a pre-desilicon removal method applied to the aforementioned pre-desilicon removal system, comprising steps S100-S400: S100, The prepared liquid produced by the evaporation unit 50 is transported to the second dissolution unit 32 for heat exchange.
[0055] For example, the heat exchange operation specifically involves: conveying the preparation liquid from the evaporator 50 at a lower temperature (approximately 70°C) to the second dissolution unit 32, where the preparation liquid flows through the heat exchange channel of the second dissolution unit 32 and undergoes indirect heat exchange with the high-temperature dissolution slurry flowing in the adjacent channel from the end of the dissolution reaction. The residual heat of the high-temperature slurry is transferred to the preparation liquid, thereby preheating the preparation liquid to the target temperature, for example, above 95°C, preferably approximately 98°C.
[0056] S200, the preparation liquid in the second leaching unit 32 is transported to the slurry grinding device 10, and the heat-exchanged preparation liquid is used to grind the ore in the slurry grinding device 10.
[0057] For example, the grinding operation specifically involves: the high-temperature blending liquid, preheated in step S100, is pumped to the slurry grinding device 10 via the conveying device 40. Inside the slurry grinding device 10, the high-temperature blending liquid, acting as a liquid medium, enters the mill along with the added bauxite for mixing and grinding. During this process, the blending liquid not only disperses and transports solid particles, but also directly transfers its heat energy to the slurry, resulting in an initial slurry with a high starting temperature and suitable solid content. The starting temperature is approximately 85-87°C, and the solid content is approximately 350-400 g / L. This creates favorable thermodynamic conditions for the subsequent pre-desiliconization reaction, ensuring that the slurry already possesses the initial temperature required for the reaction when entering the pre-desiliconization device 20, thereby reducing or eliminating the energy required for additional preheating of this portion of the slurry.
[0058] S300. The slurry in the slurry grinding device 10 is transported to the pre-desiliconization device 20 for pre-desiliconization operation.
[0059] For example, the pre-desiliconization operation specifically involves pumping the initial slurry, obtained at a higher temperature in step S200, from the outlet of the slurry grinding device 10 and conveying it to the pre-desiliconization device 20. Specifically, the pre-desiliconization device 20 includes a series of pre-desiliconization tanks 21 connected in series. The initial slurry pumped from the outlet of the slurry grinding device 10 enters the inlet of the first pre-desiliconization tank 21 in the series of pre-desiliconization tanks 21. The slurry flows sequentially through each pre-desiliconization tank 21. During this process, through the insulation design of the pre-desiliconization tank 21 or necessary auxiliary thermal compensation, the slurry is maintained at a set reaction temperature range under normal pressure, for example, 85-87°C. The total residence time of the slurry in the entire pre-desiliconization device 20 is controlled within a certain range, for example, 10-14 hours. Under these long-term insulation conditions, the less reactive silica-containing minerals such as quartz phase in the slurry can fully react with the conditioning solution and gradually transform into sodium silicate slag, which is easily separated in subsequent processes. In this embodiment, the "inert silicon" in the slurry is converted into "active silicon" and precipitated in advance, thereby significantly reducing the effective silicon content in the slurry entering the main leaching process, fundamentally improving the quality of the final liquid and the subsequent settling performance of the red mud.
[0060] S300, the slurry in the pre-desilicon tank 21 is transported to the first leaching unit 31 for heating and leaching reaction.
[0061] For example, in this embodiment, the slurry, which has undergone pre-desiliconization and is at a temperature of approximately 83°C, is pumped out from the last pre-desiliconization tank 21 and transported to the slurry tank 22 via a transfer pump. In the slurry tank 22, the slurry is thoroughly mixed with a high-temperature blending solution from another route of the conveying device 40. This mixing process raises the slurry temperature to the target feed temperature, for example, 90-92°C, and adjusts the chemical composition of the slurry, such as the concentration of alumina and alkali, to the acceptable range required by the leaching process. Subsequently, the blended slurry is pumped into the first leaching unit 31, where it flows sequentially through each stage of the heating pipes in the first leaching unit 31, is ultimately heated to the required high temperature by an external heat source, and completes the chemical reaction of alumina dissolving into the alkali solution under high pressure.
[0062] The above examples are merely illustrative of the technical content of the present invention to facilitate easier understanding by the reader, but do not imply that the implementation of the present invention is limited to these examples. Any technical extensions or re-creations made based on the present invention are protected by the present invention. The scope of protection of the present invention is defined by the claims.
Claims
1. A pre-desilicon removal system, characterized in that, include: Slurry grinding equipment; A pre-desiliconization device is connected to the slurry grinding device; The dissolution apparatus includes a first dissolution unit and a second dissolution unit, wherein the first dissolution unit is connected to the pre-desiliconization apparatus; An evaporation device is connected to the second dissolution unit; A conveying device is connected to the second leaching unit and the slurry grinding device; The evaporation device is used to produce the blended liquid; the second dissolution unit is used to heat the blended liquid from the evaporation device; the conveying device is used to convey the blended liquid from the second dissolution unit to the slurry grinding device; and the pre-desiliconization device is used to receive the slurry from the slurry grinding device and perform a pre-desiliconization reaction.
2. The pre-desiliconization system according to claim 1, characterized in that, The pre-desilicon device includes a pre-desilicon tank, which is connected to the slurry grinding device and the first leaching unit.
3. The pre-desiliconization system according to claim 2, characterized in that, Multiple pre-desilicon tanks are provided, and the multiple pre-desilicon tanks are connected in series between the slurry grinding device and the first leaching unit.
4. The pre-desiliconization system according to claim 2, characterized in that, The pre-desilicon device also includes a slurry tank, which is connected between the pre-desilicon tank and the first leaching unit.
5. The pre-desiliconization system according to claim 4, characterized in that, The pre-desiliconization device also includes a transfer pump, which is disposed between the pre-desiliconization tank and the slurry tank. The transfer pump is used to pump the slurry in the pre-desiliconization tank to the slurry tank.
6. The pre-desiliconization system according to claim 4, characterized in that, The conveying device is also connected to the slurry tank, and the conveying device is also used to convey the preparation liquid of the second leaching unit to the slurry tank.
7. The pre-desiliconization system according to claim 6, characterized in that, The conveying device includes a first pipe, a second pipe, and a three-way valve. The three-way valve is connected to the second leaching unit, the first pipe, and the second pipe. The first pipe is connected to the slurry grinding device, and the second pipe is connected to the slurry tank.
8. The pre-desiliconization system according to claim 4, characterized in that, The pre-desiliconization system further includes a solid concentration sensor disposed within the slurry tank; and / or, the pre-desiliconization system further includes a temperature sensor disposed within the slurry grinding device and / or the slurry tank.
9. The pre-desiliconization system according to claim 1, characterized in that, The leaching device is a tubular reactor, and the first leaching unit and the second leaching unit are continuous pipes in different sections of the tubular reactor.
10. A pre-desiliconization method, characterized in that, The pre-desiliconization system applied to any one of claims 1-9 comprises: The prepared liquid produced by the evaporation device is transported to the second dissolution unit for heat exchange. The preparation solution in the second leaching unit is transported to the slurry grinding device, and the heat-exchanged preparation solution is used to grind the ore in the slurry grinding device. The slurry in the slurry grinding device is transported to the pre-desiliconization device for pre-desiliconization operation; The slurry in the pre-desilicon tank is transported to the first leaching unit for heating and leaching reaction.