Lithium carbonate wastewater purification device for removing thallium and fluorine based on chemical precipitation and adsorption

Abstract

This invention relates to the field of wastewater treatment, and more particularly to a lithium carbonate wastewater purification device for thallium and fluoride removal based on chemical precipitation and adsorption. The device comprises, in sequence, a pH adjustment mechanism, an oxidation mechanism, a primary precipitation mechanism, a secondary precipitation mechanism, a filtration mechanism, an ion exchange mechanism, an activated carbon adsorption mechanism, and a discharge mechanism. The primary and secondary precipitation mechanisms utilize the same wastewater sedimentation machine, where the reacted precipitates in the wastewater, along with flocculants and micro-sand, form heavy sand flocs. These heavy sand flocs accumulate in various sedimentation tubes, forming precipitated sludge. Finally, all the precipitated sludge from the sedimentation tubes is pushed out of the wastewater tank for quick cleaning. This invention solves the technical problem of the difficulty in forming a compact solid-liquid separation layer in the sedimentation tank for thallium and fluoride precipitates during lithium carbonate wastewater treatment, leading to significant cleaning challenges.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment, and more particularly to a lithium carbonate wastewater purification device for thallium and fluoride removal based on chemical precipitation and adsorption. Background Technology

[0002] Lithium carbonate is a key raw material for the cathode material of lithium batteries. During the production process, a large amount of wastewater containing thallium and fluorine is generated. Thallium is a highly toxic heavy metal that can cause irreversible damage to the human nervous system even at trace levels. It is also extremely difficult to degrade in the environment. Excessive discharge can lead to bioaccumulation in aquatic bodies and endanger ecological security. Fluoride ions are highly corrosive and biodegradable. Excessive discharge can disrupt the acid-base balance of water bodies, leading to health risks such as dental fluorosis. Furthermore, high concentrations of fluoride can reduce the purity of lithium carbonate products, directly affecting the cycle life and safety performance of batteries.

[0003] In actual treatment, the removal of thallium and fluorine often adopts a multi-stage process such as oxidation-precipitation-sedimentation-flocculation-ion exchange to convert thallium and fluorine into precipitates. However, these precipitates are generally fine in size and have high viscosity, making it difficult to form a compact solid-liquid separation layer in the sedimentation tank. The remaining fine sediment is difficult to be completely recovered by conventional pressure filtration or centrifugation, resulting in a large difficulty in cleaning the sediment. Summary of the Invention

[0004] To overcome the drawback of thallium and fluoride precipitates formed in lithium carbonate wastewater treatment, which are difficult to form a compact solid-liquid separation layer in the sedimentation tank and thus difficult to clean, this invention provides a lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption.

[0005] The technical implementation scheme of this invention is as follows: a lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption, comprising a pH adjustment mechanism, an oxidation mechanism, a primary precipitation mechanism, a secondary precipitation mechanism, a filtration mechanism, an ion exchange mechanism, an activated carbon adsorption mechanism, and a discharge mechanism in sequence; the primary and secondary precipitation mechanisms both use the same wastewater sedimentation treatment machine; the wastewater sedimentation treatment machine includes a mounting frame, a wastewater tank, an overflow pipe, a bushing, an inlet pipe, a tee pipe, an electrically controlled lifting mechanism, a main track plate, an underwater electrically controlled translation mechanism, an intercepting filter, an inner tank, a sedimentation pipe, a push column, a fixing plate, a lifting screw, and an underwater motor; the wastewater tank is fixedly connected to the mounting frame; an overflow pipe is connected to the wastewater tank; a bushing is fixedly connected to the bottom of the wastewater tank; an inlet pipe is connected inside the bushing. Liquid pipe; a tee pipe connected to the liquid inlet pipe is fixed to the wastewater tank; an electrically controlled lifting mechanism is installed on the mounting frame; a main track plate is fixed to the electrically controlled lifting mechanism; an underwater electrically controlled translation mechanism is installed on the main track plate; an inner tank is fixed to the underwater electrically controlled translation mechanism; the inner tank has an internal cavity structure; a liquid inlet channel structure connected to the internal cavity is opened in the middle of the inner tank, and the liquid inlet pipe is connected to the liquid inlet channel; several sedimentation tubes connected to the internal cavity are fixed to the lower side of the inner tank; an intercepting filter screen tightly attached to the lower end of the sedimentation tube is fixed to the main track plate; push columns corresponding to the number and position of the sedimentation tubes are slidably connected to the inner tank; a fixing plate is fixedly connected to all push columns; a lifting screw is rotatably connected to the inner tank; the lifting screw is screwed to the fixing plate; an underwater motor that drives the lifting screw to rotate is installed on the inner tank.

[0006] As an improvement to the above scheme, the chemical precipitation reaction reagent used in the primary precipitation mechanism is a sulfiding agent; the chemical precipitation reaction reagent used in the secondary precipitation mechanism is lime milk; and the adsorption resin used in the ion exchange mechanism is CH-TI resin.

[0007] As an improvement to the above scheme, the inlet pipe is rotatably connected to the bushing; the inlet pipe is rotatably connected to the tee pipe; a driven gear is fixedly connected to the inlet pipe; a drive motor is installed on the tee pipe; a drive gear is fixedly connected to the output shaft of the drive motor; the drive gear meshes with the driven gear; and a blade is fixedly connected to the inlet pipe.

[0008] As an improvement to the above solution, a reflux channel structure connecting to the inner cavity is provided at the top of the inner liner.

[0009] As an improvement to the above solution, a sand injection pipe is connected to the top of the inner liner.

[0010] As an improvement to the above solution, a spiral guide strip structure is provided inside the liquid inlet pipe.

[0011] As an improvement to the above scheme, the sand injection pipe is connected to a fine spray pipe.

[0012] As an improvement to the above scheme, a secondary track plate is fixedly connected to the wastewater tank.

[0013] As an improvement to the above solution, a discharge through-hole structure is provided on the secondary track plate.

[0014] As an improvement to the above scheme, a waste hopper with a discharge hole is fixedly connected to the bottom of the sub-track plate; a waste collection box aligned with the bottom of the waste hopper is fixedly connected to the mounting frame.

[0015] This invention has the following advantages: This invention provides a lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption. It sequentially includes a pH adjustment mechanism, an oxidation mechanism, a primary precipitation mechanism, a secondary precipitation mechanism, a filtration mechanism, an ion exchange mechanism, an activated carbon adsorption mechanism, and a discharge mechanism. The primary and secondary precipitation mechanisms both use the same wastewater sedimentation treatment machine. The inlet pipe feeds wastewater, flocculant, and chemical precipitation reagents upwards into the inner tank. Simultaneously, the wastewater and chemical precipitation reagents produce precipitate. The precipitate is thoroughly mixed with the flocculant, and sand is injected... The micro-sand inside the pipe is sprayed downwards and collides with the upward-flowing sediment and flocculant, allowing the sprayed micro-sand to be evenly dispersed in various areas of the wastewater. The sediment, flocculant, and micro-sand together form heavy sand flocs, which then accumulate in each sedimentation pipe to form precipitated sludge. Finally, all the precipitated sludge in the sedimentation pipes is pushed out of the wastewater tank to complete the quick cleaning work. This solves the technical problem that thallium and fluoride precipitates formed in lithium carbonate wastewater treatment are difficult to form a compact solid-liquid separation layer in the sedimentation tank, making their cleaning difficult. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption. Figure 2 This is a schematic diagram of the structure of a wastewater sedimentation treatment machine; Figure 3 This is a schematic diagram of the cross-sectional structure of the wastewater tank in a wastewater sedimentation treatment machine. Figure 4 This is a schematic diagram of the inlet pipe structure of a wastewater sedimentation treatment machine; Figure 5 A schematic diagram of the main track plate structure of a wastewater sedimentation treatment machine; Figure 6 This is a schematic diagram of the cross-sectional structure of the inner tank of a wastewater sedimentation treatment machine. Figure 7 This is a schematic diagram of the cross-sectional structure of the inlet pipe of a wastewater sedimentation treatment machine.

[0017] Labels in the diagram: 1-Mounting frame, 2-Wastewater tank, 21-Overflow pipe, 22-Bushing, 23-Inlet pipe, 2301-Spiral guide strip, 24-T-pipe, 25-Driven gear, 26-Drive motor, 27-Drive gear, 28-Blade, 31-Electric lifting machine, 32-Main track plate, 33-Underwater electric translation machine, 34-Interception filter, 35-Secondary track plate, 3501-Discharge through hole, 36-Waste hopper, 37-Waste collection box, 4-Inner liner, 401-Inner cavity, 402-Inlet channel, 403-Return channel, 41-Sedimentation pipe, 42-Push column, 43-Fixing plate, 44-Lifting screw, 45-Underwater motor, 5-Sand injection pipe, 51-Fine spray pipe. Detailed Implementation

[0018] The above-described solution will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. The implementation conditions used in the embodiments may be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not specified are generally those in routine experiments.

[0019] Example 1: A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption, such as... Figure 1 As shown, the system sequentially includes a pH adjustment mechanism, an oxidation mechanism, a primary sedimentation mechanism, a secondary sedimentation mechanism, a filtration mechanism, an ion exchange mechanism, an activated carbon adsorption mechanism, and a discharge mechanism. Both the primary and secondary sedimentation mechanisms utilize the same wastewater sedimentation treatment machine. Wastewater first enters the pH adjustment mechanism to adjust the pH to 6-8. Then, it enters the oxidation mechanism to oxidize thallium. Next, it enters the primary sedimentation mechanism, where a sulfiding agent is used to react the thallium in the wastewater, forming Tl₂S and Tl(OH)₃ precipitates. The wastewater then enters the secondary sedimentation mechanism, where lime milk is used to react the fluorine in the wastewater, forming CaF₂ precipitates. The wastewater then flows through the filtration mechanism for particle filtration. Finally, it enters the ion exchange mechanism, where CH-TI₇ resin is used to deeply adsorb and remove residual thallium trace elements. The wastewater then enters the activated carbon adsorption mechanism to remove residual fluorine. Finally, the wastewater is discharged through the discharge mechanism.

[0020] A wastewater sedimentation treatment machine, such as Figures 2-6As shown, it includes a mounting frame 1, a wastewater tank 2, an overflow pipe 21, a bushing 22, an inlet pipe 23, a tee pipe 24, an electrically controlled elevator 31, a main track plate 32, an underwater electrically controlled translation machine 33, an intercepting filter screen 34, an inner tank 4, a sedimentation pipe 41, a push column 42, a fixing plate 43, a lifting screw 44, and an underwater motor 45; the wastewater tank 2 is fixedly connected to the mounting frame 1; the overflow pipe 21 is connected to the wastewater tank 2, and the overflow pipe 21 is connected to the next treatment equipment; the bushing 22 is fixedly connected to the bottom of the wastewater tank 2; A liquid inlet pipe 23 is connected inside the bushing 22; a three-way pipe 24 is fixedly connected to the wastewater tank 2, with the liquid inlet port of the three-way pipe 24 connected to the previous treatment equipment, and the bypass port of the three-way pipe 24 connected to the flocculant and chemical precipitation reaction reagent delivery equipment; the three-way pipe 24 is connected to the liquid inlet pipe 23; an electrically controlled elevator 31 is installed on the mounting frame 1; a main track plate 32 is fixedly connected to the lifting component of the electrically controlled elevator 31; an underwater electrically controlled translation machine 33 is installed on the main track plate 32, and the underwater electrically controlled translation machine 33 is guided by a transverse guide. The underwater electrically controlled translation machine 33 consists of a track and a waterproof pusher motor; an inner liner 4 is fixedly connected to the transverse guide rail component; the inner liner 4 has an inner cavity 401 structure inside; a liquid inlet channel 402 structure connecting to the inner cavity 401 is opened in the middle of the inner liner 4, and the upper outlet end of the liquid inlet pipe 23 is connected to the liquid inlet channel 402; several sedimentation pipes 41 are fixedly connected to the lower side of the inner liner 4, and the sedimentation pipes 41 are connected to the inner cavity 401; an intercepting filter screen 34 is fixedly connected to the main track plate 32; the lower outlet ends of all sedimentation pipes 41 are... The filter screen 34 is closely attached to the inner liner 4; pushers 42 are slidably connected to the inner liner 4, corresponding to the number and position of the sedimentation tubes 41, and the pushers 42 are initially located above the corresponding sedimentation tubes 41; a fixing plate 43 is fixedly connected to all pushers 42; two lifting screws 44 are rotatably connected to the inner liner 4; the two lifting screws 44 are screwed to the fixing plate 43 through a threaded structure; two underwater motors 45 are installed on the inner liner 4; the output shafts of the two underwater motors 45 are respectively fixedly connected to the corresponding lifting screws 44.

[0021] like Figure 3 and Figure 4 As shown, the inlet pipe 23 is rotatably connected to the bushing 22; the inlet pipe 23 is rotatably connected to the tee pipe 24; a driven gear 25 is fixedly connected to the inlet pipe 23; a drive motor 26 is installed on the tee pipe 24; a drive gear 27 is fixedly connected to the output shaft of the drive motor 26; the drive gear 27 meshes with the driven gear 25; three paddles 28 are fixedly connected to the inlet pipe 23; several return channels 403 structures connecting to the inner cavity 401 are opened on the top edge of the inner liner 4; a sand injection pipe 5 is connected to the top of the inner liner 4, and a micro sand conveying device is connected to the outside of the sand injection pipe 5.

[0022] When using a wastewater sedimentation treatment machine, wastewater from the previous treatment equipment flows upward into the inner cavity 401 of the inner tank 4 through the three-way pipe 24 and the inlet pipe 23. Simultaneously, an external flocculant and chemical precipitation reagent delivery device delivers the corresponding flocculant and chemical precipitation reagent to the wastewater through the three-way pipe 24. Metal elements in the wastewater react with the chemical precipitation reagent to produce precipitates, which are then thoroughly mixed with the flocculant. Simultaneously, an external micro-sand delivery device sprays micro-sand into the wastewater through the sand injection pipe 5. The downwardly sprayed micro-sand mixes thoroughly with the upwardly flowing precipitate and flocculant. The coagulant first aggregates with the fine suspended precipitate particles to form flocs, which then adhere to the surface of the micro-sand to form spherical heavy sand flocs. These heavy sand flocs have various morphologies. The sediments accumulate in each sedimentation tube 41 to form sedimented sludge. At the same time, the drive motor 26 drives the drive gear 27 to rotate. The drive gear 27 meshes with the driven gear 25 to drive the inlet pipe 23 and the paddle 28 to rotate rapidly. The paddle 28 draws the wastewater in the inner cavity 401 downwards into the wastewater tank 2 below each sedimentation tube 41. The sedimented sludge in the wastewater is intercepted by the intercepting filter screen 34 and accumulates in the sedimentation tube 41. The wastewater continuously entering the wastewater tank 2 will flow back into the inner cavity 401 through the return channel 403, allowing the residual metal elements in the wastewater to flow back into the inner cavity 401 to react with the chemical precipitation reaction reagent. The wastewater located at the top of the wastewater tank 2 flows to the next treatment device through the overflow pipe 21.

[0023] As the sludge accumulates in the sedimentation tube 41, the resistance to the wastewater flowing out of the sedimentation tube 41 increases. Therefore, it is necessary to clean the sludge accumulated in the sedimentation tube 41 regularly. First, the wastewater from the previous treatment equipment stops flowing into the inner cavity 401 of the inner tank 4. The electrically controlled elevator 31 drives the main track plate 32 and the inner tank 4 to rise and leave the wastewater tank 2. Then, the underwater motor 45 controls the lifting screw 44 to rotate. The lifting screw 44 drives the fixed plate 43 and the push column 42 to move downward. The push column 42 enters the corresponding sedimentation tube 41 to squeeze the sludge. At this time, the intercepting filter... The screen 34 remains in the sedimentation tube 41 to intercept the sedimented sludge. After the sedimented sludge is squeezed, the wastewater inside will pass through the intercepting screen 34 and be squeezed downwards. The squeezed wastewater falls back into the wastewater tank 2. Finally, the underwater electric translation machine 33 drives the inner tank 4 to the right away from the main track plate 32, the intercepting screen 34 and the wastewater tank 2. Then, the underwater motor 45 controls the lifting screw 44 to drive the fixed plate 43 and the push column 42 to continue to move downwards. The push column 42 pushes the sedimented sludge in the sedimentation tube 41 downwards, realizing the unified removal of all sedimented sludge in the sedimentation tube 41 and completing the quick cleaning of sedimented sludge.

[0024] Example 2, based on Example 1 above, as follows: Figures 2-7As shown, the inlet pipe 23 of this embodiment is provided with a plurality of spiral guide strips 2301 structures; the lower outlet end of the sand injection pipe 5 is connected to a fine spray pipe 51, and the lower outlet end of the fine spray pipe 51 is aligned with the upper outlet end of the inlet pipe 23; the wastewater, flocculant and chemical precipitation reaction reagent flow upward along the spiral guide strips 2301 of the inlet pipe 23 in a spiral motion trajectory, the wastewater and chemical precipitation reaction reagent produce precipitation, the precipitation and flocculant are fully mixed, the micro-sand in the sand injection pipe 5 is sprayed downward under high pressure through the fine spray pipe 51, the downward sprayed micro-sand collides strongly with the upward spirally flowing precipitation and flocculant, the collision can evenly disperse the sprayed micro-sand in various areas of the wastewater, so that the precipitation in the wastewater can fully contact the flocculant and the evenly dispersed micro-sand, enhance the coagulation effect of the precipitation, flocculant and micro-sand to form heavy sand flocs, and thus improve the sedimentation and collection efficiency of the precipitation.

[0025] Example 3, based on Example 1 above, as follows: Figures 2-6 As shown, in this embodiment, a secondary track plate 35 is fixedly connected to the wastewater tank 2, which is aligned with the front and rear positions of the main track plate 32. The secondary track plate 35 has a discharge through-hole 3501 structure, located on the right side of the wastewater tank 2. A waste hopper 36 connected to the discharge through-hole 3501 is fixedly connected to the bottom of the secondary track plate 35. A waste collection box 37 aligned with the bottom of the waste hopper 36 is fixedly connected to the mounting frame 1. During the process of squeezing and cleaning the sludge in the sedimentation pipe 41, the electrically controlled elevator 31 drives the main track plate 32 and the inner tank 4 upwards until the main track plate 32 aligns with the secondary track plate 35. It is then spliced ​​together with the fixed plate 43, which in turn drives the push column 42 to squeeze the sludge in the sedimentation tube 41. After the lifting screw 44 pulls the fixed plate 43 to drive the push column 42 to squeeze the sludge in the sedimentation tube 41, the underwater electric translation machine 33 pushes the inner tank 4 to move to the right along the main track plate 32 and the secondary track plate 35 to align with the discharge through hole 3501. Then, the lifting screw 44 pulls the fixed plate 43 to drive the push column 42 to push the sludge in the sedimentation tube 41 completely downward. The sludge pushed downward from the sedimentation tube 41 passes through the discharge through hole 3501 and the waste hopper 36 and falls into the waste collection box 37, completing the collection of the sludge.

[0026] Although this disclosure has been shown and described with reference to specific exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made to this disclosure without departing from the spirit and scope of the disclosure as defined by the appended claims and their equivalents. Therefore, the scope of this disclosure should not be limited to the above embodiments, but should be defined not only by the appended claims, but also by their equivalents.

Claims

1. A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption, comprising a pH adjustment mechanism, an oxidation mechanism, a primary precipitation mechanism, a secondary precipitation mechanism, a filtration mechanism, an ion exchange mechanism, an activated carbon adsorption mechanism, and a discharge mechanism in sequence; the primary and secondary precipitation mechanisms both use the same wastewater sedimentation treatment machine; Its characteristics are, The wastewater sedimentation treatment machine includes a mounting frame (1); a wastewater tank (2) is fixedly connected to the mounting frame (1); an overflow pipe (21) is connected to the wastewater tank (2); a bushing (22) is fixedly connected to the bottom of the wastewater tank (2); an inlet pipe (23) is connected inside the bushing (22); a three-way pipe (24) connected to the inlet pipe (23) is fixedly connected to the wastewater tank (2); an electric lifting machine (31) is installed on the mounting frame (1); a main track plate (32) is fixedly connected to the electric lifting machine (31); an underwater electric translation machine (33) is installed on the main track plate (32); an inner tank (4) is fixedly connected to the underwater electric translation machine (33); an inner cavity (401) structure is opened inside the inner tank (4); a connection to the inner cavity (401) is opened in the middle of the inner tank (4). The inner liner (4) has an inlet channel (402) structure, and the inlet pipe (23) is connected to the inlet channel (402); several sedimentation pipes (41) connected to the inner cavity (401) are fixedly connected to the lower side of the inner liner (4); an interception filter (34) is fixedly connected to the main track plate (32) and closely attached to the lower end of the sedimentation pipe (41); pushers (42) corresponding to the number and position of sedimentation pipes (41) are slidably connected to the inner liner (4); a fixing plate (43) is fixedly connected to all pushers (42); a lifting screw (44) is rotatably connected to the inner liner (4); the lifting screw (44) is screwed to the fixing plate (43); an underwater motor (45) that drives the lifting screw (44) to rotate is installed on the inner liner (4); a sand injection pipe (5) is connected to the top of the inner liner (4).

2. The lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 1, characterized in that, The chemical precipitation reagent used in the primary precipitation unit is a sulfiding agent; the chemical precipitation reagent used in the secondary precipitation unit is lime milk; and the adsorption resin used in the ion exchange unit is CH-TI resin.

3. The lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 1, characterized in that, The inlet pipe (23) is rotatably connected to the bushing (22); the inlet pipe (23) is rotatably connected to the tee pipe (24); a driven gear (25) is fixedly connected to the inlet pipe (23); a drive motor (26) is installed on the tee pipe (24); a drive gear (27) is fixedly connected to the output shaft of the drive motor (26); the drive gear (27) meshes with the driven gear (25); and a blade (28) is fixedly connected to the inlet pipe (23).

4. The lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 3, characterized in that, The top of the inner liner (4) is provided with a reflux channel (403) structure that connects to the inner cavity (401).

5. A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 1, characterized in that, The inlet pipe (23) is equipped with a spiral guide bar (2301) structure.

6. The lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 1, characterized in that, The sand injection pipe (5) is connected to a fine spray pipe (51).

7. A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to any one of claims 1-6, characterized in that, A secondary track plate (35) is fixedly connected to the wastewater tank (2).

8. A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 7, characterized in that, The auxiliary track plate (35) is provided with a discharge through hole (3501) structure.

9. A lithium carbonate wastewater thallium and fluoride removal purification device based on chemical precipitation and adsorption according to claim 8, characterized in that, The bottom of the sub-track plate (35) is fixed with a waste hopper (36) that connects to the discharge through hole (3501); the mounting frame (1) is fixed with a waste collection box (37) that aligns with the bottom of the waste hopper (36).

Images