A spodumene transformation device and method based on a suspension roasting technology

Abstract

The present invention discloses a spodumene transformation device and method based on a suspension roasting technology. The transformation device includes a preheating system, a front suspension roasting and transformation system, a rotary kiln roasting and transformation system, and a cooling system connected in sequence. The transformation method includes steps such as preheating treatment of spodumene concentrate, suspension roasting and transformation, rotary kiln roasting and transformation, and cooling treatment of spodumene material. The present invention first realizes the transformation of spodumene material in a very short time through the front suspension roasting and transformation system with high efficiency in the front stage, and then conducts a second transformation on the spodumene material through rotary kiln roasting, reducing the roasting time of the rotary kiln, saving energy consumption, and reducing the probability of local sintering.

Description

Technical Field

[0001] The present invention relates to the field of spodumene processing, and specifically to a spodumene transformation device and method based on a suspension roasting technology. Background Art

[0002] In industrial production, spodumene concentrate is mainly used as the raw material for lithium extraction by the sulfuric acid method. Before acidification roasting, spodumene needs to be subjected to roasting transformation treatment to transform the α-type spodumene with high density and stable chemical properties into the β-type spodumene with low density, loose structure, and capable of reacting with acids and bases. The quality of the crystal form conversion roasting directly affects the lithium extraction rate.

[0003] Traditional spodumene transformation mainly involves the rotary kiln rotating to drive the spodumene material to move from the kiln tail to the kiln head, and during this process, the spodumene material is roasted to achieve transformation. However, it is found in actual production that since the spodumene materials are stacked together in the rotary kiln, the heat transfer speed is slow. Especially for the materials inside, they need to be roasted at high temperature for a long time to complete the transformation, resulting in low transformation efficiency and high energy consumption; the internal and external materials are unevenly heated, and local sintering is likely to occur during long-term high-temperature roasting; and there is no effective supplementary measure for single roasting, so the transformation rate of spodumene cannot be guaranteed.

[0004] In addition, since the cooling method for spodumene transformation roasting in the prior art is to first cool the materials after transformation roasting through the cooling components of the grate cooler, and then crush the materials through a crusher to meet the finished product particle size requirements. It is found in production that cooling reduces the temperature of spodumene, making the spodumene harden, significantly increasing the crushing difficulty and reducing the production efficiency. And setting a grinding device to grind the spodumene materials before or during roasting greatly increases the probability of the materials sintering into dense large blocks during rotary kiln roasting. Not only does it need to be crushed, but the dense blocks also increase the crushing difficulty. Summary of the Invention

[0005] In order to overcome the above deficiencies in the prior art, the present invention provides a spodumene transformation device and method based on a suspension roasting technology.

[0006] The specific technical solution is as follows: A spodumene transformation device based on a suspension roasting technology includes a preheating system, a pre-stage suspension roasting transformation system, a rotary kiln roasting transformation system, and a cooling system.

[0007] The pre - suspension roasting transformation system includes a suspension transformation furnace, a suspension burner and a blower. A combustion injection pipe is connected to the side wall of the suspension transformation furnace. One end of the combustion injection pipe far from the side wall of the suspension transformation furnace is connected to the suspension burner. The suspension burner injects high - temperature flames into the suspension transformation furnace through the combustion injection pipe to heat the gas in the furnace and increase the furnace temperature. A ventilation pipe is also connected to the side wall of the suspension transformation furnace. One end of the ventilation pipe far from the suspension transformation furnace is connected to the air outlet of the blower. The blower blows air into the suspension transformation furnace, making the spodumene material entering the suspension transformation furnace in a suspended state. The high - temperature gas in the furnace transfers the heat generated by the burner to the material, and the material undergoes suspension roasting transformation. The opening and closing of the suspension burner, the size and direction of the flame, as well as the opening and closing of the blower, the size of the wind force and the wind direction can be adjusted adaptively according to the needs of the actual working conditions.

[0008] The pre - suspension roasting transformation system also includes a discharge pipe and an air pipe. The air pipe and the discharge pipe are connected to the rotary kiln roasting transformation system. The spodumene material and the high - temperature gas are transported between the suspension transformation furnace and the rotary kiln roasting transformation system through the discharge pipe for transporting the material and the air pipe for transporting the high - temperature gas generated by the rotary kiln roasting transformation.

[0009] The rotary kiln roasting transformation system includes a rotary kiln body and a rotary kiln burner. The kiln tail of the rotary kiln body is connected to the discharge pipe and the air pipe, and the kiln head is connected to the cooling system. Starting the rotary kiln roasting transformation system drives the spodumene material to be transported from the kiln tail to the kiln head for roasting transformation, and then the spodumene material that has undergone rotary kiln roasting transformation is transported to the cooling system for cooling treatment. The rotary kiln burner heats the gas in the kiln of the rotary kiln body to increase the kiln temperature.

[0010] The rotary kiln body is a traditional rotary kiln, which at least includes supporting rollers, thrust rollers, a cylinder, tyre, a large gear, a transmission mechanism, a kiln head hood and a smoke chamber and sealing devices, an internal heat exchange device in the kiln and a kiln lining.

[0011] The cooling system includes a pre - crusher and a cooling component connected in sequence. The feed inlet of the pre - crusher is connected to the discharge outlet of the rotary kiln body.

[0012] Further, in order to crush the spodumene material in a high - temperature state, the components in the contact area between the pre - crusher and the material are made of high - temperature - resistant and wear - resistant materials such as high - carbon or high - chromium alloy steel.

[0013] Common high - chromium alloy steel materials, such as high - carbon and high - manganese steel with ω(C): 1.0 - 1.3% and ω(Mn): 11 - 14%. The components in the material contact area, such as: main shaft, tooth roller sleeve, hammer head, etc.

[0014] Furthermore, the pre-crusher is preferably a roller crusher, including a gear roller sleeve, a main shaft, a housing, a bearing seat and a drive and transmission assembly, and the gear roller sleeve is installed on the middle section of the main shaft. The selected roller crusher can be selected from a single roller, a pair of rollers or multiple rollers according to the actual working conditions. For the cooling assembly of the pre-crusher, in the prior art, a coolant channel is usually set inside the main shaft to liquid cool the crusher, which has a better cooling effect than air cooling. However, in actual production, it is found that after the crusher has been running for a period of time, it is impacted by the material, and its gear roller sleeve or even the main shaft will be damaged. Once the coolant is not replaced in time, it will leak and pollute and wet the material and corrode the inside of the crusher, reducing product quality and production efficiency. The cooling method of the crusher in the prior art cannot meet the needs of the transformation device of the present invention. Considering the cooling effect and working condition loss comprehensively, the crusher of the present invention adopts a combined cooling method of "middle air cooling + end air liquid cooling".

[0015] Specifically, the front crusher also includes a liquid cooling component and an air cooling component. The air cooling component includes a cover body arranged outside the bearing seat and a cooling fan connected to the cover body. The main shaft includes an axial gas channel connected to the cover body and penetrating the main shaft, and a radial gas channel connected to the gear roller sleeve gas channel. The cooling gas is fed into the cover body through the cooling fan. The cooling gas enters from one end of the axial gas channel of the main shaft, and passes through the axial gas channel of the main shaft, the radial gas channel and the gear roller sleeve gas channel to realize air cooling of the main shaft and the gear roller sleeve during operation.

[0016] The liquid cooling component is arranged on both sides of the middle section of the main shaft, and includes a heat exchanger, a pump body, and a heat absorbing plate. The water outlet of the heat exchanger is connected to the pump body, and the pump body is connected to the water inlet joint of the heat absorbing plate. The water outlet joint of the heat absorbing plate is connected to the water inlet of the heat exchanger. The heat absorbing plate is arranged on the outside of both sides of the middle section of the main shaft, and the heat absorbing plate has a circulating water channel; the above connections are all connected through connecting pipes. Driven by the pump body, the coolant is forced to circulate in the liquid cooling component, and the heat absorbing plate is used to conduct the heat of the main shaft, and then the heat of the main shaft is taken away through the heat exchange between the coolant and the heat absorbing plate, and finally the heat of the entire liquid cooling component is transferred to the air through the heat exchanger. In order to ensure the cooling effect, liquid cooling components are arranged on both sides of the middle section of the main shaft, which is relatively difficult to be damaged, and the heat of the crusher is taken away through the heat absorbing plate and the coolant.

[0017] Furthermore, in order to improve the cooling effect, the connecting pipes located on both sides of the middle section of the main shaft are spirally sleeved on the outside of both sides of the middle section of the main shaft, and then multiple heat absorption plates can be connected in series and arranged around the outer side of the main shaft end to increase the heat exchange area and improve the heat exchange efficiency.

[0018] Furthermore, in order to prevent materials from entering the gear roller sleeve gas passage and causing blockage, an anti-blocking net is provided at the gas outlet of the gear roller sleeve gas passage.

[0019] Furthermore, the cooling components of the cooling system can be composed of other components of the traditional fourth-generation pusher rod grate cooler except the crusher, including upper and lower shells, grate beds, grate plates, pusher rods, wind chambers, fans and transmission systems.

[0020] Furthermore, in order to further rationally utilize resources and reduce system energy consumption, the cooling system further includes a gas delivery pipeline, which connects the cooling component and the suspension transformation furnace. The high-temperature exhaust gas generated when the cooling component cools the material is delivered to the suspension transformation furnace through the gas delivery pipeline as a heating gas to provide heat for the spodumene material in the furnace, thereby reducing system energy consumption.

[0021] Furthermore, the preheating system includes a first-stage cyclone, a second-stage cyclone, a third-stage cyclone and a fourth-stage cyclone connected in series from top to bottom, and the spodumene is gradually preheated through the first to fourth-stage cyclones. Each cyclone is provided with a feed pipe and a heat exchange pipe. The feed pipe of the upper-stage cyclone is connected to the straight section of the heat exchange pipe of the lower-stage cyclone. The upper-stage cyclone feeds the material to the lower-stage cyclone through the feed pipe. The feed pipe of the fourth-stage cyclone is connected to the suspension transformation furnace; the air inlet of the upper-stage cyclone is connected to the air outlet of the lower-stage cyclone through the heat exchange pipe. The air inlet of the fourth-stage cyclone is connected to the air outlet of the suspension transformation furnace through the heat exchange pipe, and the high-temperature gas is transmitted in the opposite direction of the material flow. The cyclone of the present invention can be regarded as any cyclone with gas-solid separation function in the prior art.

[0022] Furthermore, in order to improve the qualified rate of finished product particle size, the spodumene transformation device based on suspended roasting technology also includes a screening and dividing system, which includes a screening and dividing machine and an auxiliary crusher. The screening and dividing machine is provided with sieve holes of the same size as the finished product particle size requirement, and the discharge port of the cooling component is connected to the feed port of the screening and dividing machine. The auxiliary crusher can preferably be a hammer crusher, which further crushes the spodumene material that does not meet the finished product particle size requirement, and includes a grid screen with sieve holes of the same size as the finished product particle size requirement.

[0023] A spodumene transformation method based on suspended roasting technology, using the above-mentioned spodumene transformation device based on suspended roasting technology to roast and transform spodumene concentrate.

[0024] The spodumene transformation method comprises the following steps.

[0025] Step S1. Preheating treatment of spodumene concentrate: conveying the spodumene concentrate to a preheating system for preheating.

[0026] Step S2: Suspension roasting transformation.

[0027] The specific steps of step S2 are as follows:

[0028] Step S2.1. Convey the spodumene material obtained in step S1 to the suspension conversion furnace. The burner sprays flames into the suspension conversion furnace through the spray pipe. The temperature of the gas in the furnace rises. The blower blows air into the suspension conversion furnace. The spodumene material is fully dispersed in the furnace, in a suspended state, and surrounded by the high-temperature gas in the furnace;

[0029] Step S2.2. Heat the temperature inside the suspension conversion furnace to 950 - 1000 °C to convert the spodumene material from α-spodumene to β-spodumene.

[0030] Step S3. Roasting transformation in the rotary kiln: Reduce the air supply intensity of the blower. The spodumene material obtained in step S2.2 falls and enters the rotary kiln body of the rotary kiln roasting transformation system along the discharge pipe. Heat the calcination section temperature of the rotary kiln body to 1100 - 1150 °C to conduct the second roasting transformation on the spodumene material.

[0031] Step S4. Cooling treatment of the spodumene material.

[0032] The specific steps of step S4 are as follows:

[0033] Step S4.1. Convey the spodumene material obtained in step S3 to the pre-crusher. The pre-crusher crushes the high-temperature spodumene material to meet the particle size requirements of the spodumene finished product and conveys it to the cooling component;

[0034] Step S4.2. The cooling component cools the crushed spodumene material to the ambient temperature + 60 °C and outputs the finished product.

[0035] Furthermore, in order to improve the qualified rate of the finished product particle size, for the spodumene transformation device equipped with a screening and material distribution system, after the cooling treatment, the spodumene transformation method may further include the following steps:

[0036] Step S5. Finished product screening and post-treatment.

[0037] The specific steps of step S5 are as follows:

[0038] Step S5.1. Pass the finished product obtained in step S4.2 through the screening and material distribution machine. The finished product that meets the particle size requirements is directly output and stored in the warehouse;

[0039] Step S5.2. The finished product that does not meet the particle size requirements is conveyed to the auxiliary crusher for further crushing, and then judged by the grid screen whether it meets the finished product particle size requirements. If it meets the requirements, it is output. If it does not meet the requirements, it continues to be crushed until all the materials in this batch are output.

[0040] Furthermore, in order to reduce the system energy consumption, the high-temperature waste gas generated during the cooling treatment of the spodumene material in step S4.2 is introduced into the suspension transformation furnace through a gas transmission pipeline and used as the heat-assisted gas in step S2 to assist the pre-suspension roasting transformation system to work.

[0041] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0042] (1) The spodumene transformation device of the present invention first realizes the transformation of the spodumene material through the pre-suspension roasting transformation system with high efficiency in the front stage in a very short time, and then performs the second transformation of the spodumene material through the rotary kiln roasting system. Compared with the traditional transformation method that only uses the rotary kiln roasting, in the pre-suspension roasting transformation system in the front stage of the present invention, the gas in the suspension transformation furnace is heated by the burner and the blower blows air into the furnace. The material is fully dispersed in the furnace, and each small piece of spodumene material is surrounded by high-temperature gas. The heat transfer area is large and the heat conduction is fast, so that the combustion heat can be timely transferred to the material, and the heat transfer efficiency is high, saving fuel and roasting time; most of the spodumene materials entering the rotary kiln later have been transformed, and the rotary kiln only needs to transform the remaining part of the spodumene material. By controlling the roasting time of the rotary kiln, the probability of sintering is reduced. The material itself has a high temperature when entering the kiln, further saving the energy consumption of the rotary kiln roasting.

[0043] (2) The spodumene transformation device of the present invention can make the spodumene undergo two transformations, namely suspension roasting transformation and rotary kiln roasting transformation. Compared with single transformation, even if the spodumene material that fails to transform during suspension roasting can also be transformed in the rotary kiln body in the later stage, while saving energy and improving efficiency, the transformation rate of the method is guaranteed.

[0044] (3) The cooling system of the spodumene transformation device of the present invention directly crushes the spodumene material that is still in a high-temperature state and has low hardness and is easy to crush when it just comes out of the rotary kiln body, and then cools it, optimizing the cooling treatment timing, reducing the crushing difficulty, and solving the technical problem that the prior cooling operation makes the material hard and not easy to crush, resulting in poor crushing effect of the crusher.

[0045] (4) The crusher of the present invention uses the cooling combination of "central air cooling + end air-liquid cooling" to ensure the cooling effect of the crusher while solving the technical problems that the main shaft of the crusher is damaged during operation, resulting in coolant leakage, contaminating the material, and rusting the inside of the crusher. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the spodumene transformation device of the present invention.

[0047] Figure 2 It is a schematic diagram of the structure of the crusher of the present invention.

[0048] Figure 3 Schematic diagram of the cooling part structure of the crusher of the present invention.

[0049] Figure 4 Partial schematic diagram of the air-cooling structure of the crusher of the present invention.

[0050] Figure 5 Schematic diagram of the heat absorption plate structure of the present invention.

[0051] Figure 6 Flow chart of the spodumene transformation method of the present invention.

[0052] Wherein: 11 - primary cyclone, 12 - secondary cyclone, 13 - tertiary cyclone, 14 - quaternary cyclone, 15 - feed pipe, 16 - heat exchange pipe, 21 - suspension transformation furnace, 22 - suspension burner, 221 - fuel injection pipe, 23 - blower, 231 - air supply duct, 24 - discharge pipe, 25 - air duct, 31 - rotary kiln body, 32 - rotary kiln burner, 41 - crusher, 411 - tooth roller sleeve, 411a - tooth roller sleeve gas channel, 412 - main shaft, 412a - axial gas channel, 412b - radial gas channel, 413a - heat absorption plate, 413b - pump body, 413c - heat exchanger, 414a - cover body, 414b - cooling fan, 415 - housing, 416 - bearing seat, 417 - drive and transmission assembly, 42 - cooling component.

[0053] Single arrow indicates the flow direction of the air-cooling cooling gas; double arrow indicates the flow direction of the liquid-cooling coolant. Detailed implementation manners

[0054] To make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described below in conjunction with the accompanying drawings. The following is a relatively optimal one among multiple possible embodiments of the present invention, which is intended to provide a basic understanding of the present invention, but is not intended to identify the key or decisive elements of the present invention or limit the scope to be protected.

[0055] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation" and "connection" 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 directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0056] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the embodiments of the present invention are not limited thereto.

[0057] Refer to the appendix Figure 1, A spodumene transformation device based on the suspension roasting technology in this embodiment includes a preheating system, a pre - suspension roasting and transformation system, a rotary kiln roasting and transformation system, and a cooling system connected in sequence, where:

[0058] The pre - suspension roasting and transformation system includes a suspension transformation furnace 21, a suspension burner 22, a blower 23, a discharge pipe 24, and an air duct 25. A combustion spray pipe 221 is connected to the side wall of the suspension transformation furnace 21. One end of the combustion spray pipe 221 far from the side wall of the suspension transformation furnace 21 is connected to the suspension burner 22. High - temperature flame is sprayed into the suspension transformation furnace 21 through the suspension burner 22. The high - temperature flame heats the gas in the suspension transformation furnace 21, increasing the temperature in the furnace. A blast pipe 231 is connected to the side wall of the suspension transformation furnace 21. One end of the blast pipe 231 far from the side wall of the suspension transformation furnace 21 is connected to the air outlet of the blower 23. Air is blown into the suspension transformation furnace 21 through the blower 23, making the spodumene material entering the suspension transformation furnace 21 in a suspended state and fully dispersed in the furnace. Each small piece of spodumene material is surrounded by high - temperature gas after being heated. The heat transfer area is large and the heat conduction is fast, and the combustion heat can be timely transferred to the material.

[0059] The discharge pipe 24 and the air duct 25 are connected to the rotary kiln roasting and transformation system. The spodumene material and high - temperature gas are transported between the suspension transformation furnace 21 and the rotary kiln roasting and transformation system through the discharge pipe 24 for transporting materials and the air duct 25 for transporting high - temperature gas.

[0060] The rotary kiln roasting and transformation system includes a rotary kiln body 31 and a rotary kiln burner 32. The kiln tail of the rotary kiln body 31 is connected to the discharge pipe 24 and the air duct 25, and the kiln head of the rotary kiln body 31 is connected to the cooling system. The gas in the kiln of the rotary kiln body 31 is heated by the rotary kiln burner 32 to increase the temperature in the kiln.

[0061] The rotary kiln body 31 is a traditional rotary kiln, which at least includes supporting rollers, retaining wheels, a cylinder body, tyre rings, a large gear, a transmission mechanism, a kiln head hood, a smoke chamber and sealing devices, an internal heat exchange device in the kiln, and a kiln lining.

[0062] The cooling system includes a pre - crusher 41 and a cooling component 42 connected in sequence. The feed inlet of the pre - crusher 41 is connected to the discharge outlet of the rotary kiln body 31. First, the particle size of the spodumene material is crushed to no more than 25 mm by the pre - crusher 41, and then the crushed spodumene material is cooled to about ambient temperature + 60 °C by the cooling component 42. The particle size of the spodumene after crushing and the cooling temperature can be adjusted according to the actual working conditions.

[0063] More specifically, in order to crush spodumene materials in a high-temperature state, the components in the contact area between the pre-crusher 41 and the materials are made of high-temperature resistant and wear-resistant materials such as high-carbon or high-chromium alloy steel. Common high-chromium alloy steel materials, such as high-carbon high-manganese steel with ω(C): 1.0~1.3% and ω(Mn): 11~14%. The components in the contact area with the materials include, for example, the main shaft, the tooth roll sleeve, the hammer head, etc.

[0064] More specifically, the pre-crusher 41 is a roll crusher. As Figure 2 shown, the pre-crusher 41 includes a tooth roll sleeve 411, a main shaft 412, a liquid cooling component, an air cooling component, a housing 415, a bearing seat 416, and a drive and transmission component 417. The tooth roll sleeve 411 is installed in the middle section of the main shaft 412. The selected roll crusher can be selected from a single roll, a pair of rolls, or multiple rolls according to the actual working conditions.

[0065] As Figure 2 shown, the air cooling component includes a cover body 414a arranged outside the bearing seat 416 and a cooling fan 414b communicated with the cover body 414a. As Figure 3 shown, the main shaft 412 includes an axial gas channel 412a that is communicated with the cover body 414a and penetrates through the main shaft 412, and a radial gas channel 412b that is communicated with the tooth roll sleeve gas channel 411b. Figure 2 , Figure 3 In, the single arrow is the air cooling gas flow direction. Cooling gas is sent into the cover body 414a through the cooling fan 414b. The cooling gas enters from one end of the axial gas channel 412a of the main shaft 412, and realizes air cooling of the main shaft 412 and the tooth roll sleeve 411 during operation through the axial gas channel 412a, the radial gas channel 412b, and the tooth roll sleeve gas channel 411a of the main shaft.

[0066] As Figure 5 shown, the liquid cooling component is arranged on both sides of the middle section of the main shaft 412 and includes a heat exchanger 413c, a pump body 413b, and a heat absorption plate 413a connected in sequence. Specifically, the water outlet of the heat exchanger 413c is connected to the pump body 413b. The pump body 413b is connected to the water inlet joint of the heat absorption plate 413a. The water outlet joint of the heat absorption plate 413a is connected to the water inlet of the heat exchanger 413c. The heat absorption plate 413a is arranged outside both sides of the middle section of the main shaft 412. The heat absorption plate 413a has a circulating water channel; the above connections are all connected through connecting pipes.

[0067] Driven by the pump body 413b, the coolant circulates forcibly in the liquid cooling assembly. The heat absorption plate 413a is used to conduct the heat of the main shaft 412. Then, through the heat exchange between the coolant and the heat absorption plate 413a, the heat of the main shaft 412 is taken away. Finally, the heat of the entire liquid cooling assembly is transferred to the air through the heat exchanger 413c. The double arrow indicates the flow direction of the liquid cooling coolant. To ensure the cooling effect, liquid cooling assemblies are provided on both sides of the middle section of the main shaft where it is relatively not easily damaged. The heat of the crusher is taken away through the heat absorption plate 413a and the coolant.

[0068] Further, to improve the cooling effect, the connecting pipes located on both sides of the middle section of the main shaft are spirally sleeved outside both sides of the middle section of the main shaft. Thus, multiple heat absorption plates 413a can be arranged around the outside of both sides of the middle section of the main shaft, increasing the heat exchange area and improving the heat exchange efficiency.

[0069] As Figure 4 shown, to prevent materials from entering the gas passage 411a of the toothed roll sleeve and causing blockage, an anti-blocking net is provided at the air outlet of the gas passage 411a of the toothed roll sleeve.

[0070] More specifically, the cooling component 42 of the cooling system can be composed of other components of the traditional fourth-generation pusher bar grate cooler except for the crusher, including the upper and lower shells, the grate bed, the grate plates, the pusher bars, the air chambers, the fans, and the transmission system, etc.

[0071] More specifically, to further rationally utilize resources and reduce the system energy consumption, the cooling system further includes a gas transmission pipeline. The gas transmission pipeline connects the cooling component 42 and the suspension conversion furnace 21. The high-temperature waste gas generated when the cooling component 42 cools the materials is transported to the suspension conversion furnace 21 through the gas transmission pipeline to provide heat for the spodumene materials in the furnace, reducing the system energy consumption.

[0072] More specifically, the preheating system is a multi-stage preheating structure, which includes a first-stage cyclone 11, a second-stage cyclone 12, a third-stage cyclone 13, and a fourth-stage cyclone 14. The first to fourth-stage cyclones are connected in series from top to bottom in sequence; each stage of cyclone is provided with a blanking pipe 15 and a heat exchange pipe 16. The blanking pipe 15 of the upper-stage cyclone is connected to the straight section of the heat exchange pipe 16 of the lower-stage cyclone. The blanking pipe 15 of the fourth-stage cyclone 14 is connected to the suspension conversion furnace 21. The spodumene materials are preheated in multiple stages from the first-stage cyclone 11 through the second and third-stage cyclones to the fourth-stage cyclone 14, and then enter the suspension conversion furnace 21 for roasting and transformation; the air inlet of the upper-stage cyclone is connected to the air outlet of the lower-stage cyclone through the heat exchange pipe 16. The air inlet of the fourth-stage cyclone 14 is connected to the air outlet of the suspension conversion furnace 21 through the heat exchange pipe 16. The high-temperature gas is transferred in the direction opposite to the material flow direction.

[0073] More specifically, in order to improve the qualified rate of finished product particle size, the spodumene transformation device of the present invention can also be provided with a screening and dividing system after the cooling system, the screening and dividing system includes a screening and dividing machine and an auxiliary crusher, the screening and dividing machine is provided with a sieve hole of the same size as the finished product particle size, the discharge port of the cooling component 42 is connected to the feed port of the screening and dividing machine, and the spodumene material finished product that meets the finished product particle size requirements is output through the screening and dividing machine. Usually the finished product particle size requirement is: the finished product particle size is ≤25mm.

[0074] The auxiliary crusher is a hammer crusher, which includes a sieve with meshes of the same size as the particle size requirement of the finished product, and further crushes the spodumene material that does not meet the particle size requirement of the finished product and screens it through the sieve.

[0075] In addition, an embodiment of the present invention further provides a spodumene transformation method based on a suspended state roasting technology, comprising the following steps:

[0076] Step S1. Preheating of spodumene concentrate: transporting the spodumene concentrate to a preheating system for preheating;

[0077] Step S2. Suspension roasting transformation:

[0078] Step S2.1. The spodumene material obtained in step S1 is transported to the suspension transformation furnace 21, the suspension burner 22 sprays flames into the suspension transformation furnace 21 through the spray pipe, heats the gas in the furnace, and increases the temperature in the furnace. The blower 23 blows air into the suspension transformation furnace 21, and the spodumene material is fully dispersed in the furnace, in a suspended state, and surrounded by the high-temperature gas in the furnace;

[0079] Step S2.2. The suspension transformation furnace 21 is heated to a temperature of 950 to 1000°C to transform the spodumene material from α-type spodumene to β-type spodumene;

[0080] Step S3. Rotary kiln roasting transformation: reduce the air supply intensity of the blower 23, the spodumene material obtained in step S2.2 falls and enters the rotary kiln body 31 of the rotary kiln roasting transformation system along the discharge pipe 24, the spodumene material obtained in step S2.2 is transported to the rotary kiln body 31 of the rotary kiln roasting transformation system, the calcining section temperature of the rotary kiln body 31 is heated to 1100~1150℃, and the spodumene material is subjected to a second roasting transformation;

[0081] Step S4. Spodumene material cooling treatment:

[0082] Step S4.1. The spodumene material obtained in step S3 is conveyed to the pre-crusher 41, the pre-crusher 41 crushes the spodumene material into a particle size not greater than 25 mm, and conveys it to the cooling part 42;

[0083] Step S4.2. The cooling component 42 cools the crushed spodumene material to the ambient temperature + 60°C;

[0084] Further, in order to ensure the qualified rate of the finished product particle size, after the cooling treatment, this method may further include Step S5. Finished product screening and post-treatment:

[0085] Step S5.1. Pass the finished product obtained in Step S4.2 through a screening and feeding machine, and the finished product that meets the requirements of the finished product particle size is directly output and stored in the warehouse;

[0086] Step S5.2. The finished product that does not meet the particle size requirements is transported to an auxiliary crusher for further crushing, and then judged whether it meets the requirements of the finished product particle size through a grid screen. If it meets the requirements, it is output. If it does not meet the requirements, it continues to be crushed until all the materials in this batch are output.

[0087] Further, the high-temperature waste gas generated during the cooling treatment of the spodumene material in Step S4.2 is introduced into the suspension transformation furnace 21 through a gas transmission pipeline and used as the heat-assisted gas for Step S2 to assist the preposed suspension roasting transformation system to work.

[0088] Under the same other production conditions and product requirements, when the spodumene material is roasted in a dispersed suspension state at a furnace temperature of 950 - 1000°C for about 5 minutes, the transformation rate requirement can be achieved. For example, for spodumene concentrate with a particle size less than 75mm, when roasted in a dispersed suspension state at a furnace temperature of 950 - 1000°C for about 5min, it can reach ≥97%.

[0089] The traditional rotary kiln roasting transformation calcination time is 30min - 35min. For 1t or 2t of spodumene material with the same feeding amount, when using the transformation system and the transformation method described in this embodiment, on the premise of ensuring the transformation rate ≥97%, the subsequent rotary kiln roasting transformation calcination time is 1 / 4 of the traditional rotary kiln roasting transformation calcination time, about 7 - 8min; while not sintering, the transformation rate is increased by +0.5% - 0.8%.

[0090] The present invention can achieve both ensuring a better transformation rate and avoiding the long roasting time of the material in the rotary kiln resulting in sintering into large blocks. The comprehensive roasting transformation time is significantly less than the traditional transformation method, improving the production efficiency.

[0091] It should be noted that the models and quantities of blowers, burners, etc. can be adjusted according to actual working conditions.

[0092] In this text, the orientation terms such as front, rear, upper, and lower are defined based on the positions of the components in the drawings and their relative positions to each other, solely for the clarity and convenience of expressing the technical solution. It should be understood that they are relative concepts and can change accordingly depending on different usage and placement methods. The use of these orientation terms should not limit the scope of protection claimed in this application.

[0093] Without conflict, the above-mentioned embodiments and the features in the embodiments in this text can be combined with each other.

[0094] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A spodumene transformation device based on a suspension roasting technology, characterized in that: It includes a preheating system, a pre - suspension roasting transformation system, a rotary kiln roasting transformation system, and a cooling system connected in sequence; The pre - suspension roasting transformation system includes a suspension transformation furnace (21), a suspension burner (22), a blower (23), a discharge pipe (24), and an air duct (25). A supply air pipe (231) is connected to the side wall of the suspension transformation furnace (21), and one end of the supply air pipe (231) far from the side wall of the suspension transformation furnace (21) is connected to the air outlet of the blower (23); A fuel injection pipe (221) is connected to the side wall of the suspension transformation furnace (21), and one end of the fuel injection pipe (221) far from the side wall of the suspension transformation furnace (21) is connected to the suspension burner (22); The discharge pipe (24) and the air duct (25) are connected to the rotary kiln roasting transformation system; The rotary kiln roasting transformation system includes a rotary kiln body (31) and a rotary kiln burner (32). The kiln tail of the rotary kiln body (31) is connected to the discharge pipe (24) and the air duct (25); The kiln head of the rotary kiln body (31) is connected to the cooling system; The cooling system includes a pre - crusher (41) and a cooling component (42) connected in sequence. The feed inlet of the pre - crusher (41) is connected to the discharge outlet of the rotary kiln body (31); The pre - crusher (41) is a roll crusher, which includes a toothed roll sleeve (411), a main shaft (412), a liquid cooling component, an air cooling component, a housing (415), a bearing seat (416), and a drive and transmission component (417). The toothed roll sleeve (411) is installed in the middle section of the main shaft (412); The air cooling component includes a cover body (414a) arranged outside the bearing seat (416) and a cooling fan (414b) communicated with the cover body (414a); The main shaft (412) includes an axial gas passage (412a) communicated with the cover body (414a) and penetrating the main shaft (412), and a radial gas passage (412b) communicated with the toothed roll sleeve gas passage (411b); The liquid cooling component is arranged on both sides of the middle section of the main shaft (412), and includes a heat absorption plate (413a), a pump body (413b), and a heat exchanger (413c). The heat absorption plate (413a) is arranged outside both sides of the middle section of the main shaft (412). The water outlet joint of the heat absorption plate (413a) is connected to the water inlet of the heat exchanger (413c). The water outlet of the heat exchanger (413c) and the water inlet joint of the heat absorption plate (413a) are respectively connected to the pump body (413b).

2. The spodumene transformation device based on the suspension roasting technology according to claim 1, wherein: The preheating system includes a primary cyclone (11), a secondary cyclone (12), a tertiary cyclone (13), and a quaternary cyclone (14) connected in series from top to bottom; each cyclone is provided with a feed pipe (15) and a heat exchange pipe (16). The feed pipe (15) of the upper-stage cyclone is connected to the straight section of the heat exchange pipe (16) of the lower-stage cyclone. The feed pipe (15) of the quaternary cyclone (14) is connected to the suspension conversion furnace (21); the air inlet of the upper-stage cyclone is connected to the air outlet of the lower-stage cyclone through the heat exchange pipe (16), and the air inlet of the quaternary cyclone (14) is connected to the air outlet of the suspension conversion furnace (21) through the heat exchange pipe (16).

3. The spodumene transformation device based on the suspension roasting technology according to claim 1, characterized in that: The cooling system further includes a gas transmission pipeline that connects the cooling component (42) and the suspension conversion furnace (21).

4. The spodumene transformation device based on the suspension roasting technology according to claim 1, characterized in that: It further includes a screening and feeding system, which includes a screening and feeding machine and an auxiliary crusher. The screening and feeding machine is provided with sieve holes of the same size as the finished product particle size requirement. The discharge port of the cooling component (42) is connected to the feed port of the screening and feeding machine.

5. A spodumene transformation method based on a suspension roasting technique, characterized in that: Use the spodumene conversion device based on the suspension roasting technology as described in claim 1 to roast and convert spodumene concentrate. The spodumene conversion method includes the following steps: Step S1. Preheating treatment of spodumene concentrate: Transport the spodumene concentrate to the preheating system for preheating. Step S2. Suspension roasting conversion: Step S2.

1. Transport the spodumene material obtained in step S1 to the suspension conversion furnace (21). The suspension burner (22) sprays flames into the suspension conversion furnace (21) through the spray pipe (221) to heat the gas in the furnace. The temperature in the furnace rises. The blower (23) blows air into the suspension conversion furnace (21). The spodumene material is fully dispersed in the furnace and is in a suspended state, surrounded by the high-temperature gas in the furnace. Step S2.

2. Heat the temperature in the suspension conversion furnace (21) to 950 - 1000 °C to convert the spodumene material from α-spodumene to β-spodumene. Step S3. Rotary kiln roasting conversion: Reduce the air supply intensity of the blower (23). The spodumene material obtained in step S2.2 falls and enters the rotary kiln body (31) of the rotary kiln roasting conversion system along the discharge pipe (24). Heat the temperature in the calcination section of the rotary kiln body (31) to 1100 - 1150 °C to perform the second roasting conversion on the spodumene material. Step S4. Cooling treatment of spodumene material: Step S4.

1. Transport the spodumene material obtained in step S3 to the pre-crusher (41). The pre-crusher (41) crushes the high-temperature spodumene material to meet the particle size requirement of the spodumene finished product and transports it to the cooling component (42). Step S4.

2. The cooling component (42) cools the crushed spodumene material to the ambient temperature + 60 °C.

6. The spodumene transformation method based on the suspension roasting technology according to claim 5, characterized in that: It further includes the following steps: Step S5. Finished product screening and post-treatment: Step S5.

1. Pass the finished product obtained in step S4.2 through the screening and feeding machine. The finished product that meets the particle size requirement is directly output and stored in the warehouse. Step S5.

2. The finished products that do not meet the particle size requirements are transported to an auxiliary crusher for further crushing, and then it is judged by a grizzly screen whether the particle size requirements are met. If the requirements are met, they are output; if not, they continue to be crushed until all the materials in this batch are output.

7. The spodumene transformation method based on the suspension roasting technology according to claim 5 or 6, characterized in that: The high-temperature waste gas generated during the cooling treatment of the spodumene material in step S4.2 is introduced into the suspension transformation furnace (21) through a gas transmission pipeline to assist the pre-suspension roasting transformation system to work as the heat-assisted gas in step S2.

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