Preheating device and method for high-pressure leaching system for laterite nickel ore

Abstract

A preheating device and method for a high-pressure leaching system for laterite nickel ore, belonging to the technical field of metallurgy. The preheating device comprises a preheater (1), a steam turbine (2), a generator (3), a first-stage heater (4) and a second-stage heater (5). The first-stage heater (4) is provided with a first feeding end (41) connected to an ore pulp feeding pipe, and a first discharging end (42) connected to a second feeding end (51) of the second-stage heater (5). The second-stage heater (5) is provided with a second discharging end (52) connected to a third feeding end (11) of the preheater (1). A steam inlet (21) of the steam turbine (2) is communicated with a steam outlet (12) of the preheater (1). The steam turbine (2) is connected to the generator (3), a steam discharge end (22) of the steam turbine (2) being connected to the first-stage heater (4) so as to provide the first-stage heater (4) with a heat source by using discharged steam as a heating medium for raw materials. The generator (3) is connected to the second-stage heater (5) so as to supply power to the second-stage heater (5). The preheating device can use generated steam cyclically to enable ore pulp to be rapidly heated to a set temperature, thereby saving energy and lowering costs.

Description

Preheating device and method for high-pressure leaching system of laterite nickel ore Technical Field

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

[0002] In recent years, with the continued promotion and popularization of new energy electric vehicles and consumer electronics, global demand for lithium-ion secondary batteries has exploded. Nickel and nickel-based compounds, key materials in lithium-ion secondary batteries, are in high demand, leading to rising prices for nickel metal and nickel-based products. Globally, as environmental protection and renewable energy become increasingly popular, new energy electric vehicles and consumer electronics will become increasingly common. Until revolutionary new energy solutions emerge, lithium-ion secondary batteries will maintain a long-term monopoly. As nickel and nickel-based compounds, upstream of the supply chain, face a particularly severe supply shortage.

[0003] Nickel ore in laterite accounts for 65% to 70% of the total nickel reserves on land, making it a key mineral for smelting nickel and nickel-based compounds. Laterite nickel ore can be broadly divided into three types: limonitic, transitional, and saprolitic. Generally speaking, saprolitic nickel with a nickel content of 1.8% or more is best produced using the RKEF pyrometallurgical process, while limonitic and transitional nickel with a nickel content of 1.8% or less are best produced using hydrometallurgical processes such as high-pressure acid leaching and atmospheric pressure acid leaching. Compared to atmospheric pressure acid leaching, high-pressure acid leaching offers advantages such as high recovery, low acid consumption, short reaction time, and low cost. It is considered the optimal smelting method for limonitic and transitional laterite nickel ores, and has therefore become the preferred method for newly constructed laterite nickel hydrometallurgical smelting projects in recent years.

[0004] Publication No. CN107099679B provides a method for inhibiting aluminum leaching in a high-pressure leaching process of laterite nickel ore, comprising the steps of: adding sodium sulfate and / or potassium sulfate to a slurry of the laterite nickel ore before high-pressure leaching; preheating the mixed slurry and pumping it into an autoclave for leaching; and flashing the slurry after leaching to obtain a post-leaching slurry. Using the technical solution of the present invention, sodium sulfate and / or potassium sulfate are added to the slurry before high-pressure leaching of the laterite nickel ore, forming sodium or potassium alum at the high leaching temperature. In the prior art, the preheating stage of the laterite nickel ore generally requires preheating to a temperature above 200 degrees Celsius, consuming a large amount of heating steam. Furthermore, the steam generated in the preheater is directly discharged after treatment, resulting in heat loss and waste, which is detrimental to environmental protection, energy conservation, and cost reduction, resulting in low heat utilization efficiency, long heating time, and high cost.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to overcome the above technical deficiencies and propose a preheating device and method for a laterite nickel ore high-pressure leaching system to solve the technical problems of low heat utilization efficiency and long heating time of the preheating device in the prior art.

[0007] In order to achieve the above technical objectives, the technical solution of the present invention provides a preheating device and method for a laterite nickel ore high-pressure leaching system.

[0008] In a first aspect, the present invention provides a preheating device for a laterite nickel ore high-pressure leaching system, comprising a preheater, a steam turbine, a generator, a first-stage heater, and a second-stage heater.

[0009] The first stage heater has a first feed end connected to the slurry feed pipe and a first discharge end connected to the second feed end of the second stage heater;

[0010] The second stage heater has a second discharge end connected to the third feed end of the preheater;

[0011] The steam inlet of the steam turbine is connected to the steam outlet of the preheater, and the steam turbine is connected to the generator. The steam discharge end of the steam turbine is connected to the first stage heater, and the discharged steam is used as a heating medium for the raw material to provide a heat source for the first stage heater;

[0012] The generator is connected to the second-stage heater to provide power for the second-stage heater.

[0013] In some embodiments, the first stage heater has a steam outlet, the steam outlet is connected to a condenser, and the condensate outlet of the condenser is connected to the ore washing unit through a condensate pipe.

[0014] In some embodiments, the preheating device of the laterite nickel ore high-pressure leaching system further includes a temperature control unit, comprising a first temperature detector, a temperature riser, a temperature cooler, and a connecting pipe. The first temperature detector is disposed at the discharge end of the preheater to detect the slurry temperature. The discharge end of the preheater is in communication with the temperature riser, the temperature cooler, and the connecting pipe, and a first valve, a second valve, and a third valve are disposed at the connection between the temperature riser, the temperature cooler, and the connecting pipe, respectively. The outlets of the temperature riser, the temperature cooler, and the connecting pipe are connected to the high-pressure leaching system. When the slurry temperature detected by the first temperature detector is below a preset temperature range, the first valve opens, and the second and third valves close. When the slurry temperature detected by the first temperature detector is above the preset temperature range, the second valve opens, and the first and third valves close. When the slurry temperature detected by the first temperature detector is within the preset temperature range, the third valve opens, and the first and second valves close. The temperature riser has the same structure as the second-stage heater, and the electric heater in the temperature riser is connected to the generator. The cooler includes an inner tube body and an outer tube body, an interlayer is formed between the inner tube body and the outer tube body, the interlayer is connected to the condensate outlet of the condenser, and the inner tube body is respectively connected to the preheater and the high-pressure leaching system.

[0015] In some embodiments, the first-stage heater includes a first cylinder and a heating pipe arranged inside the first cylinder. The interior of the first cylinder is connected to the steam inlet of the turbine. One end of the heating pipe is connected to the slurry feed pipe, and the other end thereof extends spirally from one end of the first cylinder to the other end of the first cylinder and is connected to the second-stage heater. After the raw material enters the first-stage heater, it flows through the heating pipe and is passed into the second-stage heater.

[0016] In some embodiments, the second-stage heater includes a second cylinder and an electric heater disposed within the second cylinder, the electric heater being connected to the generator. A feed pipe and a discharge pipe are provided on the second cylinder, the feed pipe being in communication with the first-stage heater, and the discharge pipe being in communication with the preheater. A second temperature detector is provided between the connecting pipes of the second-stage heater and the preheater. A flow control valve is installed on the slurry feed pipe. The flow control valve is electrically connected to the second temperature detector via a controller, so that the second temperature detector detects the preheating temperature of the slurry and the flow control valve controls the slurry delivery rate based on the detected temperature.

[0017] In some embodiments, a plurality of steam inlet pipes are connected to the steam inlet of the steam turbine, and a steam valve is installed on each of the steam inlet pipes. When no steam passes through, the steam valve is in a closed state.

[0018] In a second aspect, the present invention provides a preheating method for a laterite nickel ore high-pressure leaching system, which is applicable to the preheating device for a laterite nickel ore high-pressure leaching system as described in any one of the above items, and the method comprises:

[0019] S100: After passing through the first and second stage heaters, the slurry is heated in the preheater. The high-pressure steam generated by the heating is output through the top steam outlet, enters the steam turbine and drives the turbine to work, thereby driving the generator to generate electricity;

[0020] S200: The generator provides power to the second stage heater, and the electric heater generates heat. The steam exhausted from the steam turbine enters the first stage heater through the steam discharge port, providing heat for the first stage heater.

[0021] S300: When the slurry passes through the first stage heater, it is heated by high-temperature steam. Then it enters the second stage heater and is heated by the electric heater. Finally, the slurry is discharged to the preheater through the second discharge end of the second stage heater. Finally, it is heated to the set temperature range by the preheater and then discharged. The generated steam is output to the turbine through the steam outlet for recycling.

[0022] Compared with the prior art, the beneficial effects of the present invention include: through the provision of a preheater, a steam turbine, a generator, a first-stage heater and a second-stage heater, the generated steam is passed into the steam turbine to generate electricity, and then the steam is passed into the first-stage heater as a heating medium for the raw materials, and steam power generation is used as the power supply for the second-stage heater, so that before the slurry enters the preheater, the steam and the electric heater can be used in sequence to perform two-stage preheating of the slurry, and energy is utilized in stages, so that the scheme uses the generated steam for graded preheating accordingly, and can recycle the generated steam so that the slurry can be quickly heated to the set temperature, which can save energy and reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic diagram of the overall structure of an embodiment of a preheating device and method for a laterite nickel ore high-pressure leaching system provided by the present invention;

[0024] FIG2 is a schematic structural diagram of a heater section of the preheating device and method for the laterite nickel ore high-pressure leaching system in FIG1 ;

[0025] FIG3 is a schematic structural diagram of a second-stage heater of the preheating device and method of the laterite nickel ore high-pressure leaching system in FIG1 ;

[0026] FIG4 is a flow chart of a preheating method for a laterite nickel ore high-pressure leaching system provided by the present invention.

[0027] In the figure: 1. Preheater; 11. Third feed end; 12. Steam outlet; 2. Steam turbine; 21. Steam inlet; 22. Steam discharge end; 23. Steam inlet pipe; 24. Steam valve; 3. Generator; 4. First stage heater; 41. First feed end; 42. First discharge end; 43. Steam inlet; 44. Steam discharge outlet; 45. First cylinder; 46. Heating pipe; 5. Second stage heater; 51. Second feed end; 52. Second discharge end; 53. Second cylinder; 54. Electric heater; 55. Feed pipe; 56. Discharge pipe; 57. Second temperature detector; 58. Flow control valve; 6. Temperature control unit; 61. First temperature detector; 62. Temperature increaser; 63. Temperature decreaser; 64. Connecting pipe; 65. First valve; 66. Second valve; 67. Third valve 7. High-pressure leaching system; 8. Condenser; 9. Ore washing unit. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] The present invention provides a preheating device and method for a laterite nickel ore high-pressure leaching system, which are described below.

[0030] As shown in FIG1 to FIG3 , an embodiment of the present invention provides a preheating device for a laterite nickel ore high-pressure leaching system, comprising a preheater 1 , a steam turbine 2 , a generator 3 , a first-stage heater 4 and a second-stage heater 5 .

[0031] The first stage heater 4 has a first feed end 41 connected to the slurry feed pipe and a first discharge end 42 connected to the second feed end 51 of the second stage heater 5 .

[0032] The second-stage heater 5 has a second discharge end 52 connected to the third feed end 11 of the preheater 1 .

[0033] The steam inlet 21 of the steam turbine 2 is connected to the steam outlet 12 of the preheater 1, and the steam turbine 2 is connected to the generator 3. Its steam discharge end 22 is connected to the first stage heater 4, and the discharged steam is used as a heating medium for the raw materials to provide a heat source for the first stage heater 4.

[0034] The generator 3 is connected to the second-stage heater to provide power to the second-stage heater 5 .

[0035] In this device, the first-stage heater 4 has a first feed end 41 connected to the slurry feed pipe, and a first discharge end 42 connected to the second feed end 51 of the second-stage heater 5. The second-stage heater 5 has a second discharge end 52 connected to the third feed end 11 of the preheater 1. After passing through the first-stage heater 4 and the second-stage heater 5, the slurry is heated in the preheater 1. The steam inlet 21 of the steam turbine 2 is connected to the steam outlet 12 of the preheater 1, so that the high-pressure steam generated by the heating is discharged through the top steam outlet 12, enters the steam turbine 2, and drives the steam turbine 2 to operate, thereby driving the generator 3 to generate electricity. The generator 3 is connected to the second-stage heater, and can provide power to the second-stage heater 5 through the generator 3, and generate a heat source through the electric heater 54; the steam exhaust end 22 of the steam turbine 2 is connected to the first-stage heater 4, so that the steam exhausted after passing through the steam turbine 2 enters the first-stage heater 4 through the steam exhaust end 22, providing a heat source for the first-stage heater 4; when the slurry passes through the first-stage heater 4, the slurry is heated by high-temperature steam in the first stage, and then enters the second-stage heater 5, and is heated in the second stage by the electric heater 54. Finally, the slurry is discharged to the preheater 1 through the second discharge end 52 of the second-stage heater 5, and is finally heated to the set temperature range by the preheater 1 and discharged. The generated steam is output to the steam turbine 2 through the steam outlet 12 for recycling. Through the staged utilization of energy, the slurry can be quickly heated to the set temperature.

[0036] A first-stage heater 4 is connected to the steam exhaust end 22 of the steam turbine 2, and can accommodate steam inside. As shown in Figure 1, in some possible embodiments, the first-stage heater 4 has a steam exhaust port 44. In the first-stage heater 4, the steam exhausted by the steam turbine 2 enters through the steam inlet 43 at one end thereof. As the steam enters, the internal gas is discharged through the steam exhaust port 44. In addition, the steam exhaust port 44 is connected to the condenser 8, and the condensate outlet of the condenser 8 is connected to the ore washing unit 9 through the condensate pipe. The exhausted steam is condensed by the condenser 8 to form condensate, which can be transported to the ore washing unit 9 through the condensate pipe and used as ore washing water.

[0037] In some possible embodiments, the preheating device of the laterite nickel ore high-pressure leaching system further includes a temperature regulating unit 6, which includes a first temperature detector 61, a temperature riser 62, a temperature reducer 63 and a connecting pipe 64. The first temperature detector 61 is arranged at the discharge end of the preheater 1 for detecting the temperature of the slurry discharged from the preheater 1; the discharge end of the preheater 1 is connected to the temperature riser 62, the temperature reducer 63 and the connecting pipe 64 through separate pipes, forming three material guide channels, which are respectively used to heat, cool and directly transport the slurry, and the connection points between the temperature riser 62, the temperature reducer 63 and the connecting pipe 64 are respectively provided with a first valve 65, a second valve 66 and a third valve 67. The outlets of the temperature riser 62, the temperature reducer 63 and the connecting pipe 64 are connected to the high-pressure leaching system. System 7; the discharged slurry passes through the first temperature detector 61 to detect the temperature of the slurry, wherein, when the slurry temperature detected by the first temperature detector 61 is lower than the preset temperature range, the first valve 65 is opened, the second valve 66 and the third valve 67 are closed, and the slurry is heated again by the warmer 62 and then discharged to the high-pressure leaching system 7. When the slurry temperature detected by the first temperature detector 61 is higher than the preset temperature range, the second valve 66 is opened, the first valve 65 and the third valve 67 are closed. At this time, the slurry is cooled by the cooler 63 and then discharged to the high-pressure leaching system 7. When the slurry temperature detected by the first temperature detector 61 is within the preset temperature range, the third valve 67 is opened, the first valve 65 and the second valve 66 are closed, and the slurry can be directly transported to the high-pressure leaching system 7 through the connecting pipe 64.

[0038] Specifically, in some possible embodiments, the temperature booster 62 has the same structure as the second-stage heater 5. The electric heater in the temperature booster 62 is connected to the generator 3, and the generator 3 is used to power the temperature booster 62. As shown in Figures 1 and 3, in some possible embodiments, the temperature reducer 63 includes an inner tube body and an outer tube body. A sandwich is formed between the inner and outer tube bodies, and the sandwich is connected to the condensate outlet of the condenser 8. The inner tube body is respectively connected to the preheater 1 and the high-pressure leaching system 7, so that the slurry can flow through the inner tube body to the high-pressure leaching system 7. During the transportation process, the slurry exchanges heat with the condensate through the inner tube body to achieve cooling. The temperature riser 62 has the same structure as the second-stage heater 5. The second-stage heater 5 includes a second cylinder 53 and an electric heater 54 provided inside the second cylinder 53. The electric heater 54 is connected to the generator 3. A feed pipe 55 and a discharge pipe 56 are provided on the second cylinder 53. The feed pipe 55 is connected to the first-stage heater 4, and the discharge pipe 56 is connected to the preheater 1. When the slurry flows to the second cylinder 53, it can be heated by the electric heater 54.

[0039] The first stage heater 4 can utilize the recovered steam to perform a stage of heating for the transported slurry. As shown in FIG2 , in some possible embodiments, the first stage heater 4 includes a first cylinder 45 and a heating pipe 46 provided inside the first cylinder 45 . The interior of the first cylinder 45 is connected to the steam inlet 21 of the steam turbine 2 , so that steam can pass into the interior of the first cylinder 45 . One end of the heating pipe 46 is connected to the slurry feed pipe, and the other end thereof spirally extends from one end of the first cylinder 45 to the other end of the first cylinder 45 and is connected to the second stage heater 5 . By designing the heating pipe 46 to be a spiral structure for transporting the slurry, the heat exchange efficiency is improved. After the raw material enters the first stage heater 4 , it flows through the heating pipe 46 to perform heat exchange with the steam for a stage of heating and is then sent to the second stage heater 5 .

[0040] Before the preheater 1 is started, the slurry is not preheated when passing through the first stage heater 4 and the second stage heater 5. At this time, the temperature of the slurry when entering the preheater 1 is the initial temperature, which is relatively low. After the preheater 1 has been running for a period of time, the steam generated by it will be utilized through the steam turbine 2, the generator 3, the first stage heater 4 and the second stage heater 5. During this process, the temperature of the slurry gradually increases and is maintained after the operation is stable. In order to further shorten the heating time of the slurry in the preheater 1, in some possible embodiments, a second temperature detector 57 is provided between the connecting pipe 64 of the second stage heater 5 and the preheater 1 to detect the temperature of the slurry when it enters the preheater 1. At the same time, when the slurry enters A flow control valve 58 is installed on the material pipe to regulate the fluid flow. The flow control valve 58 is electrically connected to the second temperature detector 57 through the controller. After the second temperature detector 57 detects the preheating temperature of the slurry, the second temperature detector 57 sends a temperature signal to the controller, causing the controller to trigger the flow control valve 58. The flow control valve 58 is used to control the slurry delivery flow rate according to the detected temperature. When the slurry temperature is low, the flow rate when it enters the preheater 1 is small, which can achieve rapid heating of the small flow slurry; in the process of gradual heating of the slurry, the flow rate of the slurry entering gradually increases, which can meet the heating demand of the slurry. At the same time, by increasing the flow rate, the delivery efficiency is improved, which is conducive to improving the preheating efficiency.

[0041] Furthermore, the steam turbine 2 and the generator 3 can also be connected to the steam outlet 12 of other equipment to fully utilize energy. Therefore, in some possible embodiments, a plurality of steam inlet pipes 23 are connected to the steam inlet 21 of the steam turbine 2, and a steam valve 24 is installed on each steam inlet pipe 23. When no steam passes through, the steam valve 24 is closed and will not cause steam loss. When steam passes through, the corresponding steam valve 24 automatically opens and transports the steam to the steam turbine 2.

[0042] As shown in FIG4 , an embodiment of the present invention provides a preheating method for a laterite nickel ore high-pressure leaching system 7, which is applicable to a preheating device for a laterite nickel ore high-pressure leaching system as described in any of the above embodiments. The method comprises:

[0043] S100: After passing through the first stage heater 4 and the second stage heater 5, the slurry is heated in the preheater 1. The high-pressure steam generated by the heating is output through the top steam outlet 12, enters the steam turbine 2 and drives the steam turbine 2 to work, thereby driving the generator 3 to generate electricity;

[0044] S200: The generator 3 provides power to the second-stage heater 5, and the electric heater 54 generates heat. The steam exhausted from the steam turbine 2 enters the first-stage heater 4 through the steam discharge port 22, providing heat for the first-stage heater 4.

[0045] S300: When the slurry passes through the first stage heater 4, it is heated by high-temperature steam. Then it enters the second stage heater 5 and is heated by the electric heater 54. Finally, the slurry is discharged to the preheater 1 through the second discharge end 52 of the second stage heater 5. Finally, it is heated to the set temperature range by the preheater 1 and then discharged. The generated steam is output to the turbine 2 through the steam outlet 12 for recycling.

[0046] The present invention also provides a more specific embodiment to illustrate the above steps S100 to S300:

[0047] Step 1: The slurry first passes through the first stage heater 4 and the second stage heater 5, and is then heated directly in the preheater 1. The high-pressure steam generated by the heating is output through the top steam outlet 12, enters the steam turbine 2 and drives the steam turbine 2 to work, thereby driving the generator 3 to generate electricity.

[0048] Step 2: The generator 3 provides power to the second-stage heater 5, and the electric heater 54 generates a heat source; the steam discharged after passing through the steam turbine 2 enters the first-stage heater 4 through the steam discharge end 22, providing a heat source for the first-stage heater 4, so that the temperature of the subsequent slurry gradually increases and is maintained after the operation is stable. During this process, the preheating temperature of the slurry is detected after the second-stage heater 5 by the second temperature detector 57, and the flow control valve 58 is triggered by the controller. The flow control valve 58 is used to control the slurry delivery flow rate according to the detected temperature. When the slurry temperature is low, the flow rate when it enters the preheater 1 is small. As the slurry gradually heats up, the flow rate of the slurry entering gradually increases.

[0049] Step 3: When the slurry passes through the first-stage heater 4, it is heated by high-temperature steam. Then it enters the second-stage heater 5 and is heated by the electric heater 54. Finally, the slurry is discharged to the preheater 1 through the second discharge end 52 of the second-stage heater 5. Finally, it is heated by the preheater 1 and discharged. The generated steam is output to the turbine 2 through the steam outlet 12.

[0050] Step 4. The slurry discharged from the preheater 1 is tested for temperature by the first temperature detector 61. When the slurry temperature detected by the first temperature detector 61 is lower than the preset temperature range, the first valve 65 is opened, the second valve 66 and the third valve 67 are closed, and the slurry is heated again by the warmer 62 and then discharged to the high-pressure leaching system 7. When the slurry temperature detected by the first temperature detector 61 is higher than the preset temperature range, the second valve 66 is opened, the first valve 65 and the third valve 67 are closed. At this time, the slurry is cooled by the cooler 63 and then discharged to the high-pressure leaching system 7. When the slurry temperature detected by the first temperature detector 61 is within the preset temperature range, the third valve 67 is opened, the first valve 65 and the second valve 66 are closed, and the slurry can be directly transported to the high-pressure leaching system 7 through the connecting pipe 64.

[0051] The present invention provides a preheater 1, a steam turbine 2, a generator 3, a first-stage heater 4, and a second-stage heater 5. After the generated steam is passed into the steam turbine 2 to generate electricity, the steam is then passed into the first-stage heater 4 as a heating medium for the raw materials. Steam power generation is used as the power supply for the second-stage heater 5. Therefore, before the slurry enters the preheater 1, the steam and the electric heater are used in sequence to perform two-stage preheating on the slurry. Energy is utilized in stages, so that the scheme uses the generated steam for graded preheating accordingly, and the generated steam can be recycled so that the slurry can be quickly heated to the set temperature, which can save energy and reduce costs.

[0052] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this application. Unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" 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, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0053] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0054] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A preheating device for a laterite nickel ore high pressure leaching system, It is characterized in that Including preheater, steam turbine, generator, first stage heater and second stage heater, The first stage heater has a first feed end connected to the slurry feed pipe and a first discharge end connected to the second feed end of the second stage heater; The second stage heater has a second discharge end connected to the third feed end of the preheater; The steam inlet of the steam turbine is connected to the steam outlet of the preheater, and the steam turbine is connected to the generator, and its steam discharge end is connected to the first stage heater, so that the discharged steam is used as a heating medium for the raw material to provide a heat source for the first stage heater; The generator is connected to the second-stage heater to provide power for the second-stage heater.

2. The preheating device of the laterite nickel ore high pressure leaching system according to claim 1, It is characterized in that The first stage heater has a steam outlet, the steam outlet is connected to a condenser, and the condensate outlet of the condenser is connected to the ore washing unit through a condensate pipe.

3. The preheating device of the laterite nickel ore high pressure leaching system according to claim 2, It is characterized in that The preheating device of the laterite nickel ore high-pressure leaching system further includes a temperature regulating unit, which includes a first temperature detector, a temperature riser, a temperature reducer and a connecting pipeline. The first temperature detector is arranged at the discharge end of the preheater to detect the slurry temperature; The discharge end of the preheater is connected to the temperature riser, the temperature reducer and the connecting pipe respectively, and the connection points between the temperature riser, the temperature reducer and the connecting pipe are respectively provided with a first valve, a second valve and a third valve, and the outlets of the temperature riser, the temperature reducer and the connecting pipe are connected to the high-pressure leaching system; Specifically, when the slurry temperature detected by the first temperature detector is lower than a preset temperature range, the first valve is opened, and the second valve and the third valve are closed; when the slurry temperature detected by the first temperature detector is higher than the preset temperature range, the second valve is opened, and the first valve and the third valve are closed; when the slurry temperature detected by the first temperature detector is within the preset temperature range, the third valve is opened, and the first valve and the second valve are closed.

4. The preheating device of the laterite nickel ore high pressure leaching system according to claim 3, It is characterized in that The temperature booster has the same structure as the two-stage heater, and the electric heater in the temperature booster is connected to the generator.

5. The preheating device of the laterite nickel ore high pressure leaching system according to claim 3, It is characterized in that The cooler comprises an inner tube body and an outer tube body, An interlayer is formed between the inner tube body and the outer tube body, the interlayer is connected to the condensate outlet of the condenser, and the inner tube body is respectively connected to the preheater and the high-pressure leaching system.

6. The preheating device of the laterite nickel ore high pressure leaching system according to claim 1, It is characterized in that The first stage heater comprises a first cylinder and a heating tube arranged inside the first cylinder. The interior of the first cylinder is connected to the steam inlet of the turbine, one end of the heating pipe is connected to the slurry feed pipe, and the other end thereof spirally extends from one end of the first cylinder to the other end of the first cylinder, and is connected to the second-stage heater, so that after the raw material enters the first-stage heater, it flows through the heating pipe and is passed into the second-stage heater.

7. The preheating device of the laterite nickel ore high pressure leaching system according to claim 1, It is characterized in that The second stage heater comprises a second cylinder and an electric heater arranged inside the second cylinder. The electric heater is connected to the generator, and a feed pipe and a discharge pipe are provided on the second cylinder. The feed pipe is connected to the first stage heater, and the discharge pipe is connected to the preheater.

8. The preheating device of the laterite nickel ore high pressure leaching system according to claim 1 or 7, It is characterized in that A second temperature detector is provided between the connecting pipe between the second stage heater and the preheater. A flow control valve is installed on the slurry feed pipe, and the flow control valve is electrically connected to the second temperature detector through a controller to detect the preheating temperature of the slurry through the second temperature detector, and the slurry delivery flow is controlled by the flow control valve according to the detected temperature.

9. The preheating device of the laterite nickel ore high pressure leaching system according to claim 1, It is characterized in that The steam inlet of the steam turbine is connected to a plurality of steam inlet pipes, each of which is equipped with a steam valve. When no steam passes through, the steam valve is in a closed state.

10. A preheating method for a laterite nickel ore high pressure leaching system, It is characterized in that A preheating device for a laterite nickel ore high pressure leaching system according to any one of claims 1 to 9, the method comprising: S100: After passing through the first stage heater and the second stage heater, the slurry is heated in the preheater. The high-pressure steam generated by the heating is output through the top steam outlet, enters the steam turbine and drives the steam turbine to work, thereby driving the generator to generate electricity; S200: The generator provides power to the second stage heater and generates heat source through the electric heater; the steam exhausted after passing through the steam turbine enters the first stage heater through the steam exhaust end to provide heat source for the first stage heater; S300: When the slurry passes through the first stage heater, it is heated by high-temperature steam, and then enters the second stage heater, where it is heated by an electric heater. Finally, the slurry is discharged to the preheater through the second discharge end of the second stage heater, and finally, it is heated to the set temperature range by the preheater and then discharged. The generated steam is output to the steam turbine through the steam outlet for recycling.

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