Device system for slurrying and decomposing rare earth ore concentrate by using sulfuric acid

Abstract

The invention discloses a device system for slurrying and decomposing rare earth ore concentrate by sulfuric acid, which comprises a slurrying and decomposing system, the slurrying and decomposing system comprises a reaction kettle, a stirring unit is arranged in the reaction kettle, the top of the reaction kettle is provided with a feed port, a liquid inlet and an exhaust port, and the bottom of the reaction kettle is provided with a discharge hole; the feeding system comprises a concentrate feeding unit and an acid leaching liquid preheating unit, the concentrate feeding unit is fixedly communicated with the feeding port, and the acid leaching liquid preheating unit is fixedly communicated with the liquid inlet; the slurry cooling system comprises a slurry cooling unit and a filtering unit; the tail gas treatment system comprises a tail gas treatment unit and a tail gas acid storage tank, the tail gas acid storage tank is communicated with the tail gas treatment unit, and the tail gas treatment unit is communicated with the exhaust port; wherein the reaction kettle is provided with a heating assembly. The reaction kettle is directly connected with the tail gas treatment unit, so that the tail gas recovery procedure in the rare earth mineral smelting process is reduced, and the tail gas treatment cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of hydrometallurgy, and in particular to a device system for decomposing rare earth concentrate by sulfate pulping. Background Art

[0002] The main fluorine-containing rare earth minerals include Sichuan fluorocarbon cerium ore, Mountain Pass ore, mixed rare earth concentrate, etc. At present, fluorocarbon cerium ore mainly adopts the oxidation roasting-hydrochloric acid leaching process. First, the fluorocarbon cerium ore is oxidized and roasted at a temperature of about 500℃-600℃. After roasting, the concentrate is converted into fluorine oxide rare earth, rare earth oxide and rare earth fluoride. Then, low-concentration hydrochloric acid is used for leaching to obtain a good slag and rare earth chloride (less cerium) solution. The good slag is then subjected to alkali conversion, water washing and defluorination, hydrochloric acid dissolution and other processes to obtain rare earth chloride solution and cerium-rich slag. After impurities are removed, the rare earth chloride solution is extracted and separated to produce pure rare earth products. The process is long and the acid and alkali consumption is large. Among them, fluorine is discharged in the form of fluorine-containing wastewater through the alkali conversion process, which poses a serious threat to the ecological environment. The mixed rare earth concentrate uses mixed rare earth concentrate decomposition technology, which mainly includes concentrated sulfuric acid high-temperature roasting decomposition process and concentrated alkali solution atmospheric pressure decomposition process. The concentrated sulfuric acid high-temperature roasting and decomposition process is to mix rare earth concentrate with concentrated sulfuric acid and roast it at 400-1000℃. During the reaction, the concentrate and concentrated sulfuric acid will quickly transform from a solid-liquid mixed phase to a pure solid phase. When the mineral particles are too large, the internal reaction will be incomplete, affecting the rare earth decomposition rate. In addition, the process produces a large amount of high-temperature mixed acid tail gas (SO 2 、SO 3 , H 2 SO 4 , HF, S iF 4 ), the sulfate wastewater and radioactive waste residue are difficult to treat, resulting in a huge and costly environmental treatment engineering system.

[0003] Based on the above technical problems, the present invention provides a device system for decomposing rare earth concentrate by sulfate slurry. Summary of the invention

[0004] The purpose of the present invention is to provide a device system for decomposing rare earth concentrate by sulfate pulping to solve the problems existing in the prior art.

[0005] To achieve the above object, the present invention provides the following solution: The present invention provides a device system for decomposing rare earth concentrate by sulfate pulping, comprising:

[0006] A slurry decomposition system, the slurry decomposition system comprises a reactor, a stirring unit is installed in the reactor, a feed inlet, a liquid inlet and an exhaust port are provided at the top of the reactor, and a discharge hole is provided at the bottom of the reactor;

[0007] A feeding system, the feeding system comprising a concentrate feeding unit and an acid leaching liquid preheating unit, the concentrate feeding unit is fixedly connected to the feed port, and the acid leaching liquid preheating unit is fixedly connected to the liquid inlet;

[0008] A slurry cooling system, the slurry cooling system comprising a slurry cooling unit and a filtering unit, the slurry cooling unit is connected to a feed end of the filtering unit, the feed end of the slurry cooling unit is fixedly connected to the discharge hole, and the discharge end of the filtering unit is fixedly connected to a feed end of the acid leaching liquid preheating unit;

[0009] A tail gas treatment system, the tail gas treatment system comprising a tail gas treatment unit and a tail gas acid storage tank, the tail gas acid storage tank is connected to the tail gas treatment unit, and the tail gas treatment unit is connected to the exhaust port;

[0010] Wherein, the reactor is provided with a heating component.

[0011] According to the device system for sulfuric acid slurry decomposition of rare earth concentrate provided by the present invention, the concentrate feeding unit includes a crusher and a screener, the crusher discharge end is connected to the screener feed end, and the screener discharge end is connected to the feed port through a conveying track.

[0012] According to the device system for decomposing rare earth concentrate by sulfate pulping provided by the present invention, the acid leaching solution preheating unit includes a heater, the heater is connected to the reactor and the heater, and the feed end of the heater is connected to the filtering unit.

[0013] According to the device system for sulfate slurry decomposition of rare earth concentrate provided by the present invention, the slurry cooling unit includes a cooling tank, the stirring unit is installed on the cooling tank, a cooler is arranged outside the cooling tank, a slurry inlet and a slurry outlet are opened on the side wall of the cooling tank, the slurry inlet is located above the slurry outlet, the slurry inlet and the discharge port of the cooler are fixedly connected by a first connecting pipe, the slurry outlet and the feed end of the cooler are fixedly connected by a second connecting pipe, a circulating pump is installed on the second connecting pipe, and a slag discharge port is opened at the bottom of the cooling tank.

[0014] According to the device system for sulfate slurry decomposition of rare earth concentrate provided by the present invention, the stirring unit includes a stirring motor fixedly connected to the cooling tank and the reactor respectively, the output shaft of the stirring motor is fixedly connected to a stirring paddle, and the stirring paddles of the two stirring motors extend into the cooling tank and the reactor respectively.

[0015] According to the device system for sulfate pulping and decomposing rare earth concentrate provided by the present invention, the filtering unit includes a filter, the feed end of the filter is connected to the slag discharge port at the bottom of the cooling tank, and the discharge end of the filter is connected to the feed end of the heater.

[0016] According to the device system for sulfate slurry decomposition of rare earth concentrate provided by the present invention, the tail gas treatment system includes a condenser, the exhaust port is fixedly connected to a buffer tank, the condenser air inlet is fixedly connected to the buffer tank, and the condenser water outlet is connected to the tail gas acid storage tank.

[0017] According to the device system for sulfate slurry decomposition of rare earth concentrate provided by the present invention, the heating component includes a jacket mounted outside the reactor, a heating chamber is formed between the jacket and the reactor, and the heating chamber is fixedly connected with a circulating air hole, and the circulating air hole is fixedly connected with the heater through a pipeline.

[0018] The present invention discloses the following technical effects:

[0019] When the present invention is used, the acid leaching liquid enters the acid leaching liquid preheating unit, enters the reactor after being heated, the rare earth concentrate enters the reactor through the concentrate feeding unit, the slurry is stirred and reacted in the reactor through the stirring unit, the reactor is indirectly heated by the heating component, the slurry reacts continuously during the heating process, the generated tail gas enters the tail gas treatment unit, and the tail gas acid obtained by condensation flows into the tail gas acid storage tank. After the reaction is completed, the slurry is pumped into the slurry cooling unit, the slurry is cooled in the slurry cooling unit, and after the slurry is cooled to a certain temperature, the solid-liquid separation is performed through the filtering unit to obtain the acid leaching liquid and the acid leaching residue, and the acid leaching liquid is supplemented with sulfuric acid and continuously enters the acid leaching liquid preheating unit.

[0020] The present invention provides an acid leaching liquid preheating unit to heat the acid leaching liquid to a specified temperature in advance, so that the acid leaching liquid can be mixed with the fluorine-containing rare earth mineral more completely and fully, thereby reducing the energy consumption pressure during the reaction process and only requiring lower energy to ensure the reaction temperature.

[0021] The present invention not only ensures the reaction temperature but also prevents moisture introduced by direct heating through the provision of an external heating component, thereby ensuring the acid concentration of the tail gas.

[0022] The reactor of the present invention is directly connected to the tail gas treatment unit, which reduces the tail gas recovery process in the rare earth mineral smelting process and reduces the tail gas treatment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic structural diagram of the device system for decomposing rare earth concentrate by sulfate pulping of the present invention;

[0025] Figure 2 The present invention is a flowchart of the system for decomposing rare earth concentrate by sulfate pulping.

[0026] Among them, 1. concentrate feeding unit; 2. heater; 3. reactor; 4. cooling tank; 5. cooler; 6. circulation pump; 7. stirring motor; 8. stirring paddle; 9. condenser; 10. buffer tank; 11. tail gas acid storage tank; 12. jacket. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Reference Figure 1-Figure 2 The present invention provides a device system for decomposing rare earth concentrate by sulfate pulping, comprising:

[0030] The slurry decomposition system comprises a reactor 3, a stirring unit is installed in the reactor 3, a feed inlet, a liquid inlet and an exhaust port are provided at the top of the reactor 3, and a discharge hole is provided at the bottom of the reactor 3;

[0031] A feeding system, the feeding system comprising a concentrate feeding unit 1 and an acid leaching liquid preheating unit, the concentrate feeding unit 1 is fixedly connected to the feed port, and the acid leaching liquid preheating unit is fixedly connected to the liquid inlet;

[0032] A slurry cooling system, the slurry cooling system comprising a slurry cooling unit and a filtering unit, the slurry cooling unit is connected to a feed end of the filtering unit, the feed end of the slurry cooling unit is fixedly connected to the discharge hole, and the discharge end of the filtering unit is fixedly connected to a feed end of the acid leaching liquid preheating unit;

[0033] A tail gas treatment system, the tail gas treatment system comprising a tail gas treatment unit and a tail gas acid storage tank 11, the tail gas acid storage tank 11 is connected to the tail gas treatment unit, and the tail gas treatment unit is connected to the exhaust port;

[0034] Wherein, the reaction kettle 3 is provided with a heating component.

[0035] When the present invention is used, the acid leaching liquid enters the acid leaching liquid preheating unit, enters the reactor 3 after being heated, the rare earth concentrate enters the reactor 3 through the concentrate feeding unit 1, the slurry is stirred and reacted in the reactor 3 through the stirring unit, the reactor 3 is indirectly heated by the heating component, the slurry reacts continuously during the heating process, the generated tail gas enters the tail gas treatment unit, and the tail gas acid obtained by condensation flows into the tail gas acid storage tank 11. After the reaction is completed, the slurry is pumped into the slurry cooling unit, the slurry is cooled in the slurry cooling unit, and after the slurry is cooled to a certain temperature, the solid-liquid separation is performed through the filtering unit to obtain the acid leaching liquid and the acid leaching residue, and the acid leaching liquid is continuously added with sulfuric acid and enters the acid leaching liquid preheating unit.

[0036] The present invention provides an acid leaching liquid preheating unit to heat the acid leaching liquid to a specified temperature in advance, so that the acid leaching liquid can be mixed with the fluorine-containing rare earth mineral more completely and fully, thereby reducing the energy consumption pressure during the reaction process and only requiring lower energy to ensure the reaction temperature.

[0037] The present invention not only ensures the reaction temperature but also prevents moisture introduced by direct heating through the provision of an external heating component, thereby ensuring the acid concentration of the tail gas.

[0038] The reactor 3 of the present invention is directly connected to the tail gas treatment unit, which reduces the tail gas recovery process in the rare earth mineral smelting process and reduces the tail gas treatment cost.

[0039] According to a further optimization scheme, the concentrate feed unit 1 includes a crusher and a screener, the discharge end of the crusher is connected to the feed end of the screener, and the discharge end of the screener is connected to the feed port through a conveyor track. After the crusher crushes the ore, it is screened and enters the reactor 3.

[0040] According to a further optimized solution, the acid leaching solution preheating unit comprises a heater 2, the heater 2 is connected to the reaction kettle 3 and the heater 2, and the feed end of the heater 2 is connected to the filtering unit.

[0041] A further optimized solution is that the slurry cooling unit includes a cooling tank 4, the stirring unit is installed on the cooling tank 4, a cooler 5 is arranged outside the cooling tank 4, a slurry inlet and a slurry outlet are opened on the side wall of the cooling tank 4, the slurry inlet is located above the slurry outlet, the slurry inlet and the discharge port of the cooler 5 are fixedly connected through a first connecting pipe, the slurry outlet and the feed end of the cooler 5 are fixedly connected through a second connecting pipe, a circulating pump 6 is installed on the second connecting pipe, and a slag discharge port is opened at the bottom of the cooling tank 4.

[0042] The circulation pump 6 inputs the slurry in the cooling tank 4 into the cooler 5 , and the slurry is cooled in the cooler 5 and then flows back into the cooling tank 4 .

[0043] According to a further optimization scheme, the stirring unit includes a stirring motor 7 fixedly connected to the cooling tank 4 and the reactor 3 respectively, and the output shaft of the stirring motor 7 is fixedly connected to a stirring paddle 8, and the stirring paddles 8 of the two stirring motors 7 extend into the cooling tank 4 and the reactor 3 respectively.

[0044] According to a further optimization scheme, the filtering unit includes a filter, a feed end of the filter is connected to the slag discharge port at the bottom of the cooling tank 4 , and a discharge end of the filter is connected to the feed end of the heater 2 .

[0045] According to a further optimization scheme, the tail gas treatment system includes a condenser 9 , the exhaust port is fixedly connected to a buffer tank 10 , the air inlet of the condenser 9 is fixedly connected to the buffer tank 10 , and the water outlet of the condenser 9 is connected to the tail gas acid storage tank 11 .

[0046] In this embodiment, the condenser 9 includes a shell and an annular condenser tube arranged in the shell. The inner wall of the condenser tube is provided with barrier members at equal intervals. The barrier members include two parallel barrier plates. A plurality of air holes are arrayed on the barrier plates, and the air holes on the two barrier plates are staggered. A plug rod is fixedly connected at the middle position of the upper barrier plate, and a sliding hole is opened at the center position of the lower barrier plate. The plug rod is inserted into the sliding hole, and a spring is provided between the two barrier plates. The space between the two barrier plates is filled with fiber fabric.

[0047] According to a further optimized solution, the heating assembly includes a jacket 12 which is sleeved outside the reactor 3, a heating chamber is formed between the jacket 12 and the reactor 3, a circulating air hole is fixedly connected to the heating chamber, and the circulating air hole is fixedly connected to the heater 2 through a pipeline.

[0048] Example:

[0049] 2.4m 3The acid leaching solution with a mass fraction of 60% enters the acid leaching solution preheating unit, is heated to 130°C and then enters the reactor 3. 600 kg of rare earth concentrate enters the reactor 3 through the concentrate feeding unit 1. The slurry is stirred and reacted in the reactor 3 for 3 hours. The reactor 3 is indirectly heated by the jacket 12 to maintain the temperature at 130°C. The slurry reacts continuously during the heating process, and the generated tail gas enters the tail gas buffer tank 10. The heavy components in the tail gas return to the reactor 3 in the tail gas buffer tank 10. The remaining tail gas enters the condenser 9, and the tail gas acid obtained by condensation flows into the tail gas acid storage tank 11. A total of 0.43m of tail gas acid is collected. 3 After the reaction is completed, the slurry is pumped into the cooling tank 4, and the slurry enters the cooler 5 through the circulation pump 6 in the cooling tank 4, and is cooled to 80°C in the cooler 5 and then returned to the cooling tank 4. After the slurry is cooled to 80°C, the acid leaching liquid and the acid leaching residue are obtained by solid-liquid separation. After the acid leaching liquid is supplemented with sulfuric acid, it continuously enters the acid leaching liquid preheating unit.

[0050] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, 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 the present invention.

[0051] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A device system for decomposing rare earth concentrate by sulfate pulping, characterized in that: include: A slurry decomposition system, the slurry decomposition system comprising a reactor (3), a stirring unit installed in the reactor (3), a feed inlet, a liquid inlet and an exhaust port opened at the top of the reactor (3), and a discharge hole opened at the bottom of the reactor (3); A feeding system, the feeding system comprising a concentrate feeding unit (1) and an acid leaching liquid preheating unit, the concentrate feeding unit (1) being fixedly connected to the feed port, and the acid leaching liquid preheating unit being fixedly connected to the liquid inlet; A slurry cooling system, the slurry cooling system comprising a slurry cooling unit and a filtering unit, the slurry cooling unit is connected to a feed end of the filtering unit, the feed end of the slurry cooling unit is fixedly connected to the discharge hole, and the discharge end of the filtering unit is fixedly connected to a feed end of the acid leaching liquid preheating unit; An exhaust gas treatment system, the exhaust gas treatment system comprising an exhaust gas treatment unit and an exhaust gas acid storage tank (11), the exhaust gas acid storage tank (11) being in communication with the exhaust gas treatment unit, and the exhaust gas treatment unit being in communication with the exhaust port; Wherein, the reaction kettle (3) is provided with a heating component.

2. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 1, characterized in that: The concentrate feeding unit (1) comprises a crusher and a screener, the discharge end of the crusher is connected to the feed end of the screener, and the discharge end of the screener is connected to the feed port via a conveying track.

3. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 1, characterized in that: The pickling liquid preheating unit comprises a heater (2), the heater (2) is connected to the reaction kettle (3) and the heater (2), and the feed end of the heater (2) is connected to the filtering unit.

4. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 3 is characterized in that: The slurry cooling unit comprises a cooling tank (4), the stirring unit is installed on the cooling tank (4), a cooler (5) is arranged outside the cooling tank (4), a slurry inlet and a slurry outlet are provided on the side wall of the cooling tank (4), the slurry inlet is located above the slurry outlet, the slurry inlet and the discharge port of the cooler (5) are fixedly connected via a first connecting pipe, the slurry outlet and the feed end of the cooler (5) are fixedly connected via a second connecting pipe, a circulating pump (6) is installed on the second connecting pipe, and a slag discharge port is provided at the bottom of the cooling tank (4).

5. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 4, characterized in that: The stirring unit comprises a stirring motor (7) fixedly connected to the cooling tank (4) and the reaction kettle (3), respectively; the output shaft of the stirring motor (7) is fixedly connected with a stirring paddle (8); the stirring paddles (8) of the two stirring motors (7) extend into the cooling tank (4) and the reaction kettle (3), respectively.

6. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 5, characterized in that: The filtering unit comprises a filter, the feed end of the filter is connected to the slag discharge port at the bottom of the cooling tank (4), and the discharge end of the filter is connected to the feed end of the heater (2).

7. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 1, characterized in that: The tail gas treatment system comprises a condenser (9), the exhaust port is fixedly connected to a buffer tank (10), the air inlet of the condenser (9) is fixedly connected to the buffer tank (10), and the water outlet of the condenser (9) is connected to the tail gas acid storage tank (11).

8. The device system for decomposing rare earth concentrate by sulfate pulping according to claim 1, characterized in that: The heating component comprises a jacket (12) sleeved outside the reaction kettle (3), a heating chamber is formed between the jacket (12) and the reaction kettle (3), a circulating air hole is fixedly connected on the heating chamber, and the circulating air hole is fixedly connected to the heater (2) through a pipeline.

Images