Rare earth carbonate production system and production method

Abstract

The application discloses a rare earth carbonate production system and a production method, and belongs to the field of rare earth materials; the production system fully utilizes the characteristics that the supernatant in the precipitation reactor has few impurities and has certain heat; after impurities are filtered again through a filter, evaporation and concentration are directly carried out through an evaporator to obtain high-temperature steam and concentrated ammonium chloride solution; the concentrated ammonium chloride solution can be used to recycle ammonium chloride through a subsequent crystallization process; the obtained high-temperature steam provides heat for maintaining the reaction temperature of the precipitation reactor through a heat exchanger, and the cooled high-temperature steam finally becomes recyclable industrial wastewater.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rare earth materials, and particularly relates to a rare earth carbonate production system and a production method. BACKGROUND

[0002] As a precursor for preparing rare earth fluorescent powder, rare earth polishing powder, rare earth permanent magnet material, hydrogen storage material and structural material, rare earth carbonate is an important rare earth material. In the prior art, rare earth chloride solution can be reacted with carbonate precipitants to obtain rare earth carbonate. For example, various metal chlorides are prepared into metal carbonates by using ammonium bicarbonate precipitation method. A large amount of wastewater is generated in the preparation process, and a large amount of ammonia nitrogen and chlorine ions exist in the wastewater, which cannot be directly discharged or recycled, so that wastewater treatment becomes a big problem. SUMMARY

[0003] In view of the above technical problems, the present application aims to provide a rare earth carbonate production system and a production method, which at least solve the problem that a large amount of ammonia nitrogen and chlorine ions exist in the wastewater and cannot be recycled.

[0004] The technical scheme adopted by the present application is as follows:

[0005] According to a first aspect of the present application, a rare earth carbonate production system is provided, which comprises: a precipitation reactor for precipitation reaction and aging reaction of rare earth chloride solution and carbonate precipitants; a filter for filtering supernatant sucked from the precipitation reactor; an evaporator for evaporating and concentrating the filtered supernatant to obtain high-temperature steam and concentrated liquid; and a heat exchanger for heat exchange between the high-temperature steam obtained by the evaporator and a circulating heating device of the precipitation reactor.

[0006] In a possible implementation, the production system further comprises: a centrifugal separation device for centrifugal separation of slurry in the precipitation reactor; and a waste liquid storage pool for storing waste liquid separated by centrifugation, which is pumped into the evaporator after being filtered by the filter.

[0007] In a possible implementation, the production system further comprises: a condensing device for cooling steam after heat exchange in the heat exchanger.

[0008] In a possible implementation, a circulating pipeline is additionally arranged between the heat exchanger and the condensing device, and a temperature detector is arranged on the circulating pipeline. When the temperature of steam discharged from the heat exchanger is higher than a set value, the steam is returned to the heat exchanger for further heat exchange. If the temperature is lower than the set value, the steam is discharged into the condensing device.

[0009] In a possible implementation, a steam buffer tank is additionally arranged on the circulating pipeline.

[0010] In a possible implementation, the precipitation reactor comprises a tank body, a stirrer is arranged inside the tank body, the tank body has a sandwich structure, heating pipes are arranged in the sandwich, and a suction tube is arranged in the tank body and connected with a filter.

[0011] In a possible implementation, the filter comprises a cylinder body and a filter core, the filter core is arranged in the center of the cylinder body, an inlet of feed liquid is formed at the bottom edge of the filter core, and the inlet of the feed liquid is opposite to a pipe orifice of a feed liquid input pipe arranged on the cylinder body; an annular partition plate is arranged on the outer wall of the filter core and above the inlet of the feed liquid, the annular partition plate divides the cylinder body into a lower filter cavity and an upper filtrate cavity, the filtrate cavity is connected with a feed liquid output pipe; the feed liquid input pipe is connected with the precipitation reactor, and the feed liquid output pipe is connected with the evaporator through a feed liquid conveying pump.

[0012] In a possible implementation, the production system further comprises a clean water pool, the clean water pool is used for storing condensed water after heat exchange of the heat exchanger, and a waste liquid storage pool is arranged in the clean water pool, and heat can be transferred between the waste liquid in the waste liquid storage pool and the hot water in the clean water pool.

[0013] According to a second aspect of the present disclosure, the present application provides a rare earth carbonate production method, which applies the above production system, and comprises the following steps: S1, adding high-purity rare earth chloride feed liquid into the precipitation reactor, adding high-purity carbonate precipitant under stirring, and performing reaction until the pH of supernatant is stable at 6-7 and the concentration of rare earth metal ions in the supernatant is lower than 0.03 mol / L; the temperature of the system is maintained at 50-80 DEG C during the precipitation process; S2, after the precipitation is completed, the supernatant in the precipitation reactor is separately sucked out to the evaporator to perform evaporation and concentration to obtain concentrated liquid, and the concentrated liquid is used to recover ammonium chloride through a crystallization process; the remaining slurry in the precipitation reactor is delivered to a centrifugal separation device through a slurry pump to perform centrifugal dewatering, and rare earth carbonate and waste liquid are separated; S3, the separated rare earth carbonate is washed again with deionized water, and finally, ultra-high-purity and low-impurity rare earth carbonate is obtained through centrifugal dewatering.

[0014] The present application has the advantages that the present application provides a rare earth carbonate production system and production method, the production system fully utilizes the characteristics that the supernatant in the precipitation reactor has few impurities and has certain heat, the impurities are filtered again through the filter, and then the supernatant is directly evaporated and concentrated through the evaporator to obtain high-temperature steam and concentrated liquid of ammonium chloride; the concentrated liquid of ammonium chloride can be used to recover ammonium chloride through a subsequent crystallization process; the high-temperature steam is used to provide heat for maintaining the reaction temperature of the precipitation reactor through the heat exchanger, and the cooled high-temperature steam finally becomes industrial waste water that can be recycled. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 FIG. 1 is a schematic diagram of a rare earth carbonate production system provided by an embodiment of the present application.

[0016] Figure 2 is a schematic diagram of a second rare earth carbonate production system provided by an embodiment of the present application.

[0017] Figure 3 is a structural schematic diagram of a precipitation reactor provided by an embodiment of the present application.

[0018] Figure 4 is a structural display diagram of a filter provided by an embodiment of the present application.

[0019] Figure 5 is Figure 4 a display diagram of the internal structure of the filter.

[0020] Figure 6 is a three-dimensional structural schematic diagram of a filter improvement scheme provided by an embodiment of the present application.

[0021] Figure 7 is a schematic diagram of a circulating heat supply system with an evaporator and a heat exchanger as the core provided by an embodiment of the present application.

[0022] Figure 8 is a schematic diagram of a composite pool composed of a waste liquid storage pool and a clean water pool provided by an embodiment of the present application.

[0023] Figure 9 , 10 is a detection report of lanthanum carbonate prepared by an embodiment of the present application by using high-purity ammonium carbonate solution as a precipitant.

[0024] Figure 11 , 12 is a detection report of cerium carbonate prepared by an embodiment of the present application by using high-purity ammonium carbonate solution as a precipitant.

[0025] BRIEF DESCRIPTION OF DRAWINGS: Precipitation reactor 1, tank body 101, stirrer 102, filler port 103, heating pipe 104, suction tube 105; filter 2, barrel 201, filter element 202, end cap 203, feed liquid inlet 204, feed liquid input pipe 205, annular partition 206, feed liquid output pipe 207; evaporator 3, heat exchanger 4, condensing equipment 5, centrifugal separation equipment 6, waste liquid storage pool 7, clean water pool 8, circulating pipeline 9, steam buffer tank 10.

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0027] Embodiments of the present application are described below in detail with reference to the accompanying drawings, wherein the same or similar components are denoted by the same or similar reference numerals, and wherein examples of the embodiments are shown in the drawings. The embodiments described below are exemplary, and are merely intended to explain the present application, and should not be understood as limiting the present application.

[0028] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, and are merely intended to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0029] In addition, the terms "first", "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified and limited, the term "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication between the two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0030] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication between the two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] In the prior art, the production of rare earth carbonate mainly involves a precipitation reactor and a centrifugal separation device, and the process flow is as follows: the rare earth chloride feed liquid is stirred and reacted with a carbonate precipitant in the precipitation reactor, and then is allowed to stand and age; during the production process of the precipitation reactor, the temperature needs to be maintained at 50-80℃, so the precipitation reactor is generally provided with a circulating heating device; in the prior art, the fluid medium of the circulating heating device mainly adopts high-temperature steam or hot water, and the heat source is mainly electricity or fossil fuel combustion. After the standing and aging of the precipitation reactor is completed, the reaction liquid is directly pumped into the centrifugal separation device for primary centrifugal dewatering to obtain rare earth carbonate and primary waste liquid containing a large number of impurities; the primary waste liquid is stored in a waste liquid storage tank and waits for subsequent treatment; a large amount of ammonia nitrogen and chlorine ions exist in the primary waste liquid and cannot be directly discharged or recycled, which makes the treatment of the waste liquid a big problem. In addition, the temperature of the primary waste liquid just separated is above 30℃, which gradually cools down with time, causing waste of heat.

[0032] Therefore, the present application provides a rare earth carbonate production system, which is shown in Figure 1 which shows a schematic diagram of a rare earth carbonate production system provided by an embodiment of the present application, and the system mainly comprises a plurality of precipitation reactors 1, filters 2, evaporators 3, heat exchangers 4, condensing devices 5 and clean water tanks 8.

[0033] Based on the above-mentioned devices, the production system of the present application adopts a process flow different from the above, which is as follows: first, the rare earth chloride feed liquid is stirred and reacted with a carbonate precipitant in the precipitation reactor 1, and then is allowed to stand and age; after the standing and aging are completed, the supernatant in the precipitation reactor 1 is separately pumped out by the present application, filtered by the filter 2 to remove particulate impurities, and then pumped into the evaporator 3 for evaporation and concentration; the evaporation and concentration can simultaneously obtain high-temperature steam; in the present application, the evaporator 3 preferably adopts electric heating, which can quickly and efficiently generate high-temperature steam. Then, the high-temperature steam is sent to the heat exchanger 4; the circulating heating device of the precipitation reactor 1 is coupled with the heat exchanger 4, and heat is obtained by heat exchange between the heat exchanger 4 and the high-temperature steam to provide a continuous and stable heat source for the precipitation reactor 1. The high-temperature steam after heat exchange is condensed by the condensing device 5, and the cooling liquid is sent to the clean water tank 8 for storage and reuse. The concentrated liquid in the evaporator 3 that is evaporated and concentrated to a certain extent is discharged to a vacuum crystallizer to recover ammonium chloride.

[0034] The production system of the present application fully utilizes the characteristics that the supernatant in the precipitation reactor 1 has less particulate impurities and itself has a certain amount of heat, and after the impurities are filtered again by the filter 2, the supernatant is directly evaporated and concentrated by the evaporator 3 to obtain high-temperature steam and concentrated liquid of ammonium chloride; the concentrated liquid of ammonium chloride can recover ammonium chloride through subsequent crystallization process; the obtained high-temperature steam provides heat for the precipitation reactor 1 to maintain the reaction temperature through the heat exchanger 4, and the cooled high-temperature steam finally becomes industrial wastewater that can be recycled.

[0035] Compared with the prior art described above, the production system of the embodiment of the present application reasonably utilizes the characteristics of the supernatant in the precipitation reactor 1, and converts part of the waste liquid with less ammonia nitrogen and chloride ions into industrial wastewater that can be recycled. In addition, the production system of the embodiment of the present application provides heat for maintaining the reaction temperature of the precipitation reactor 1.

[0036] Further, in the above embodiment, only the supernatant in the precipitation reactor 1 is utilized, and the remaining reaction liquid in the precipitation reactor 1 still needs to be pumped into the centrifugal separation device 6 according to the original process flow to obtain rare earth carbonate and first-stage waste liquid containing many impurity particles. The first-stage waste liquid is stored in the waste liquid storage tank 7 and waits for subsequent treatment. The embodiment of the present application also includes this part of the waste liquid in the treatment process; specifically, the supernatant in the waste liquid storage tank 7 is pumped into the evaporator 3 after filtering impurities by the filter 2. In this way, this part of the waste liquid is treated, and more steam source is provided for the evaporator 3. The corresponding rare earth carbonate production system of this improvement is shown in Figure 2 , which mainly includes a plurality of precipitation reactors 1, filters 2, evaporators 3, heat exchangers 4, condensing devices 5, centrifugal separation devices 6, waste liquid storage tanks 7, clean water tanks 8, and the like.

[0037] Further, the rare earth carbonate obtained by centrifugal dewatering in the embodiment of the present application is washed by water leaching to remove chloride ions and other impurity ions, and then is centrifugally dewatered, cooled and dried to obtain rare earth carbonate.

[0038] The above describes the basic structure and working principle of the two production systems of the embodiment of the present application. The specific devices in the system are described below.

[0039] As shown in Figure 3 , it is a structure schematic diagram of a precipitation reactor 1 provided by the embodiment of the present application. The precipitation reactor 1 includes a tank body 101, and a stirrer 102 is arranged inside the tank body 101. The stirrer 102 is driven by a motor at the top. Two filling ports 103 are arranged on the cover body at the top of the tank body 101, which are respectively used for adding rare earth chloride liquid and carbonate precipitant. The tank body 101 is provided with a sandwich structure, and a heating pipe 104 is spirally arranged in the sandwich. The inlet of the heating pipe 104 is located at the lower right corner in the figure, and the outlet is located at the upper left corner. Hot water flows in from the inlet at the lower right corner, spirally rises along the tank body 101, and flows out from the outlet at the upper left corner. A discharge port is arranged at the bottom of the tank body 101, and the discharge port is connected with a slurry pump. The slurry in the tank body 101 is pumped into the centrifugal separation device 6 by the slurry pump. In addition, as shown in the figure, a liquid suction pipe 105 is arranged at the right side in the tank body 101. The liquid suction pipe 105 is vertically arranged, and a plurality of liquid suction holes are distributed on the liquid suction pipe 105. The bottom of the liquid suction pipe 105 extends to the middle lower part of the tank body 101, and the upper end of the liquid suction pipe 105 penetrates out of the tank body 101 and is connected with the filter 2.

[0040] AsFigure 4 and Figure 5 The diagram shown is a structural illustration of a filter 2 provided in an embodiment of this application. The filter 2 includes a cylindrical body 201 and a filter element 202; a detachable end cap 203 is provided at the bottom of the cylindrical body 201, and the filter element 202 is installed in the center of the end cap 203; after assembly (i.e.... Figure 5 (As shown in the diagram), filter element 202 is located in the center of cylinder 201. A liquid inlet 204 is formed at the bottom edge of filter element 202, which is directly opposite to the opening of liquid input pipe 205 provided on cylinder 201. An annular baffle 206 (preferably made of rubber) is provided on the outer wall of filter element 202 above liquid inlet 204. The annular baffle 206 divides cylinder 201 into a lower filtration chamber and an upper filtrate chamber. The filtrate chamber is connected to liquid output pipe 207. In this embodiment, valves are provided on both liquid input pipe 205 and liquid output pipe 207. Liquid input pipe 205 is connected to suction pipe 105 on sedimentation reactor 1, and liquid output pipe 207 is connected to evaporator 3 through liquid delivery pump.

[0041] The working principle of the above-mentioned filter 2 is that the supernatant drawn from the sedimentation reactor 1 enters the filter element 202 through the feed liquid inlet pipe 205, and after being filtered by the filter element 202, it enters the filtrate chamber formed between the filter element 202 and the cylinder 201, and is then discharged into the evaporator 3 through the feed liquid outlet pipe 207.

[0042] Furthermore, such as Figure 6 As shown, this is an improved filter scheme provided by an embodiment of the present application. In this scheme, each sedimentation reactor 1 is equipped with two parallel filters 2, and the two filters 2 are used alternately to ensure continuous production.

[0043] like Figure 7 The figure shows a schematic diagram of a circulating heating system based on an evaporator 3 and a heat exchanger 4, as provided in an embodiment of this application. As shown in the figure, in this embodiment, the evaporator 3 is an electric steam generator, which is equipped with multiple packing ports, a discharge port, and a steam outlet. The supernatant extracted from the sedimentation reactor 1 and the supernatant in the waste liquid storage tank 7 are filtered by the filter 2 and enter the evaporator 3 through the packing ports. High-temperature steam is quickly generated by heating and sent to the heat exchanger 4. In the heat exchanger 4, the high-temperature steam exchanges heat with the water in the heat exchange circulation pipeline of the sedimentation reactor 1, and then is condensed into liquid by the condensing device 5 and sent to the clear water tank 8 for storage.

[0044] Furthermore, in order to make fuller use of the high-temperature steam generated by evaporator 3, such as Figure 7As shown, a circulating pipeline 9 is added between the heat exchanger 4 and the condensing device 5, and a temperature detector is arranged on the circulating pipeline 9. When the steam temperature discharged from the heat exchanger 4 is higher than a set value, for example, 80℃, the steam is returned to the heat exchanger 4 for continuous use. If the temperature is lower than the set value, the steam is discharged into the condensing device 5. In addition, a steam buffer tank 10 is added on the circulating pipeline 9 to increase the total amount of steam flow in the circulating pipeline 9.

[0045] As shown, a waste liquid storage tank 7 and a clean water tank 8 are combined together. The waste liquid storage tank 7 is maintained at a high temperature by using the waste heat of the high-temperature steam after heat exchange in the heat exchanger 4. In this scheme, the condensing device 5 is cancelled. Figure 8 As shown, the waste liquid storage tank 7 is arranged in the clean water tank 8. The waste liquid storage tank 7 can be multiple. The waste liquid storage tank 7 is made of an acid- and alkali-resistant heat-conducting material, for example, a metal barrel coated with acid- and alkali-resistant paint. The fluid after heat exchange in the heat exchanger 4 is sent to the bottom of the clean water tank 8 through a pipeline. In this embodiment, a plurality of pipelines are laid at the bottom of the clean water tank 8, and a plurality of holes are opened on the pipelines. In addition, the clean water tank 8 and the waste liquid storage tank 7 are sealed with a cover to reduce heat loss. Figure 8

[0046] The above is a detailed introduction to the production system provided by the present application. Next, the present application further provides a method for preparing rare earth carbonate by using the above production system. The preparation process of lanthanum carbonate is taken as an example for illustration, which includes the following steps:

[0047] In step S1, the high-purity lanthanum chloride solution is added into a precipitation reactor. Under stirring, a high-purity carbonate precipitant, for example, a high-purity ammonium bicarbonate solution or a high-purity ammonium carbonate solution, is added. The reaction is carried out until the pH of the supernatant is stable at 6-7, and the concentration of rare earth metal ions in the supernatant is less than 0.03 mol / L. The temperature of the system is maintained at 50-80℃ during the precipitation process.

[0048] In a preferred embodiment, the high-purity lanthanum chloride solution is obtained by the following method: using the characteristic that an organic extractant preferentially combines with rare earth, the rare earth in the rare earth solution is extracted by using the organic extractant, and the non-rare earth impurity ions are left in the raffinate. Then, the organic extractant loaded with the rare earth is washed with acid to obtain the high-purity lanthanum chloride solution. The purity of the obtained rare earth solution can reach 99.999%, and the content of non-rare earth impurity ions is less than 20 ppm.

[0049] ​In a preferred embodiment, ammonia water is used to absorb carbon dioxide to prepare high-purity ammonium carbonate solution as a precipitant. The preparation method is as follows: food-grade carbon dioxide and ammonia water (ammonia water concentration is 10 mol / L) are mixed in a proportion of 0.16-0.24:1, and a high-concentration ammonium carbonate solution is prepared in a carbon dioxide absorber. Then, the concentration is reduced to the production requirement by adding pure water.

[0050] Step S2: After the precipitation is completed, the precipitation is aged for 0.5-1.0 hours; the aging process is carried out at a temperature of 50-80℃.

[0051] Step S3: After the aging is completed, the supernatant in the precipitation reactor is separately pumped out to an evaporator for evaporation and concentration to obtain a concentrated solution, and the concentrated solution is recovered by a crystallization process; the remaining slurry in the precipitation reactor is transported to a centrifugal separation device by a slurry pump for centrifugal dewatering to separate out rare earth carbonate and waste liquid.

[0052] Step S4: The separated rare earth carbonate is washed with deionized water to remove chloride ions and other impurity ions in the rare earth carbonate, and finally, ultra-high-purity, low-impurity rare earth carbonate is obtained by centrifugal dewatering.

[0053] As shown in Figure 9 , 10 , it is a detection report of lanthanum carbonate prepared by the high-purity ammonium carbonate solution as a precipitant according to the embodiment of the present application. The above process is also applicable to the production of ultra-high-purity cerium carbonate, as shown in Figure 11 , 12 , it is a detection report of cerium carbonate prepared by the high-purity ammonium carbonate solution as a precipitant according to the embodiment of the present application. Through detection, the rare earth impurity content in the lanthanum carbonate and cerium carbonate prepared by the process of the present application is less than 0.00002%, and the non-rare earth impurity content is mostly less than 0.0001%.

[0054] It can be understood that the present application is described by some embodiments, and those skilled in the art know that various changes or equivalent replacements can be made to these features and embodiments without departing from the spirit and scope of the present application. In addition, under the guidance of the present application, these features and embodiments can be modified to adapt to specific conditions and materials without departing from the spirit and scope of the present application. Therefore, the present application is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the present application are within the scope of protection of the present application.

Claims

1. A rare earth carbonate production system, characterized by, The application relates to a production system for high-purity rare earth chloride, which comprises the following components: a precipitation reactor (1) for precipitation reaction and aging reaction of rare earth chloride solution and a carbonate precipitant; a filter (2) for filtering supernatant extracted from the precipitation reactor (1); an evaporator (3) for evaporating and concentrating the filtered supernatant to obtain high-temperature steam and concentrated solution; a heat exchanger (4) for heat exchange between high-temperature steam obtained by the evaporator (3) and a circulating heating device of the precipitation reactor (1); a centrifugal separation device (6) for centrifugal separation of slurry in the precipitation reactor (1); and a waste liquid storage tank (7) for storing waste liquid separated by centrifugal separation, which is filtered by the filter (2) and then pumped into the evaporator (3); and a clean water tank (8) for storing condensed water after heat exchange of the heat exchanger (4), wherein the waste liquid storage tank (7) is arranged in the clean water tank (8), heat can be transferred between the waste liquid in the waste liquid storage tank (7) and the hot water in the clean water tank (8), and the fluid after heat exchange of the heat exchanger (4) is sent into the bottom of the clean water tank (8) through a pipeline, and the waste liquid temperature in the waste liquid storage tank (7) is maintained by using the waste heat of the high-temperature steam after heat exchange of the heat exchanger (4). A circulating pipeline (9) is additionally arranged between the heat exchanger (4) and the clean water tank (8), and a temperature detector is arranged on the circulating pipeline (9), so that when the steam temperature discharged from the heat exchanger (4) is higher than a set value, the steam is returned to the heat exchanger (4) for continuous heat exchange, and when the steam temperature is lower than the set value, the steam is discharged into a condensing device (5). A steam buffer tank (10) is additionally arranged on the circulating pipeline (9). The precipitation reactor (1) comprises a tank body (101), an agitator (102) is arranged in the tank body (101), the tank body (101) has a sandwich structure, heating pipes (104) are arranged in the sandwich, a liquid suction pipe (105) is arranged in the tank body (101), and the liquid suction pipe (105) is connected with the filter (2). The filter (2) comprises a cylinder body (201) and a filter core (202), the filter core (202) is located in the center of the cylinder body (201), a liquid inlet (204) is formed at the bottom edge of the filter core (202), the liquid inlet (204) is opposite to a liquid inlet pipe (205) arranged on the cylinder body (201), an annular partition plate (206) is arranged on the outer wall of the filter core (202) and above the liquid inlet (204), the annular partition plate (206) divides the cylinder body (201) into a lower filtering cavity and an upper filtrate cavity, the filtrate cavity is connected with a liquid outlet pipe (207), the liquid inlet pipe (205) is connected with the precipitation reactor (1), and the liquid outlet pipe (207) is connected with the evaporator (3) through a liquid conveying pump. The application further discloses a production method of high-purity rare earth chloride by using the production system, which comprises the following steps: S1, adding high-purity rare earth chloride solution into the precipitation reactor, adding high-purity carbonate precipitant under stirring, and reacting until the supernatant pH is stable at 6-7 and the rare earth metal ion concentration in the supernatant is lower than 0.03 mol / L; and the temperature of the system is maintained at 50-80 DEG C during the precipitation process. ​ 2. The rare earth carbonate production system according to claim 1, characterized by, ​ 3. The rare earth carbonate production system according to claim 2, wherein ​ 4. The rare earth carbonate production system according to claim 1, characterized by, ​ 5. The rare earth carbonate production system according to claim 1, wherein ​ 6. A method for producing a rare earth carbonate, characterized by, ​ ​ Step S2, after the precipitation is finished, the precipitation is aged, and the aging process maintains a temperature of 50-80°C; Step S3, after the aging is finished, the supernatant in the precipitation reactor is separately pumped out to an evaporator to be evaporated and concentrated to obtain a concentrated solution, the concentrated solution is recycled to recover ammonium chloride through a crystallization process; the remaining slurry in the precipitation reactor is transported to a centrifugal separation device through a slurry pump to be centrifugally dewatered, and rare earth carbonate and waste liquid are separated out; Step S4, the separated rare earth carbonate is washed with deionized water, and finally, ultra-high purity and low-impurity rare earth carbonate is obtained through centrifugal dewatering.

7. The method for producing rare earth carbonate according to claim 6, characterized in that, The high-purity carbonate precipitant is a high-purity ammonium bicarbonate solution or a high-purity ammonium carbonate solution.

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