Efficient sodium metavanadate purification system

Abstract

The invention provides an efficient sodium metavanadate purification system, and belongs to the technical field of high-purity vanadium processing. A plurality of compression rollers and guide rollers for tensioning and pulling the upper filter belts are rotationally connected to the rack; the upper filter belts and the lower filter belts are pulled on the rack to form a feeding station, a first filter pressing station, a first water adding station, a second filter pressing station, a second water adding station, a third filter pressing station, a discharging station and a cleaning station which are arranged in sequence; the upper surface of the lower filter belt is coated with a cement-containing material through a feeding mechanism at the feeding station, and the upper filter belt and the lower filter belt are in an overlapped state at the first filter pressing station, the second filter pressing station and the third filter pressing station; the upper filter belt and the lower filter belt are in a separated state at the first water adding station and the second water adding station; the device further comprises a filtrate collecting tank and a cleaning liquid collecting tank, the cleaning station performs backwashing through water curtains arranged on the upper filter belt and the lower filter belt, and the cleaning liquid collecting tank collects cleaning liquid after the upper filter belt and the lower filter belt are cleaned. The method has the advantages of high efficiency and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of high-purity vanadium processing and relates to a high-efficiency sodium metavanadate purification system. Background Art

[0002] The high-purity vanadium production process involves placing vanadium pentoxide (defective product) into an electrically heated reactor, adding water, and heating and stirring. When the water temperature reaches 60-80°C, heating is stopped, stirring is continued at a constant temperature for one hour, and the mixture is filtered while hot. The filtrate is then transferred to a reactor. A small amount of CaCl2 powder is then added, and the mixture is adjusted to alkalinity with alkali solution. The mixture is heated and filtered, and the filtrate is placed into a vanadium precipitation tank. The mixture is naturally cooled, and an appropriate amount of NH4Cl is added to precipitate the vanadium. Ammonium metavanadate is then sent to the vanadium baking workshop to produce high-purity vanadium. The wastewater from precipitation can be reused to dissolve the defective vanadium pentoxide by heating. The entire production process is continuous. The reactor is a general-purpose piece of equipment, while the vanadium baking furnace is a specialized piece of equipment. To save costs, filtration after the addition of CaCl2 is typically performed using a filter press. Drainage (centrifugal drainage) is required before filtration. This process requires numerous pieces of equipment and frequent material turnover, negatively impacting waste, pollution, and costs.

[0003] During the processing of high-purity vanadium, the following reactions are mainly carried out in the reactor: V2O5+NaOH→NaVO3+H2O (vanadium raw material solid turns into liquid), Fe 2+ +2OH - →Fe(OH)2(iron precipitation), Ca 2+ +2OH - →Ca(OH)2 (calcium precipitation), in addition, a small amount of calcium hydrogen phosphate, calcium hydrogen sulfate and other precipitates will be produced. After adding CaCL2, the calcium precipitation eliminates the alkalinity (Ca 2+ +2OH - →Ca(OH)2), and the resulting mixture contains solids such as Fe(OH)2, Ca(OH)2, a small amount of calcium hydrogen phosphate and a small amount of calcium hydrogen sulfate, and a solution of water and NaVO3. Since the water solubility of NaVO3 is not high, even at a temperature suitable for dissolution (more than 70 degrees), the water content in the solution is relatively high, and the mixture cannot be directly processed by a filter press (when the residue content is low, the operating efficiency of the filter press is extremely low, and the residue dehydration rate does not meet the requirements). Therefore, it is more common in the prior art to use a method of draining first and then filter pressing for dehydration.

[0004] In addition, since the purpose of the reactor treatment in high-purity vanadium processing is mainly to convert the solid vanadium raw material into liquid, although the water content in the filter residue after pressure filtration is already low, "vanadium" still exists in it, and the filter residue needs to be washed and then filtered.

[0005] In summary, in the existing high-purity vanadium processing technology, the process of separating the "vanadium"-containing liquid from the mixture has defects such as complex procedures, multiple equipment conversions, and the need for reprocessing of filter residues. Summary of the Invention

[0006] The purpose of the present invention is to provide a sodium metavanadate efficient purification system in view of the above-mentioned problems existing in the existing technology. The technical problem to be solved by the present invention is how to simplify the process and improve the efficiency.

[0007] The object of the present invention can be achieved by the following technical solutions: A sodium metavanadate efficient purification system, characterized in that it comprises a frame, an upper filter belt connected end to end and a lower filter belt connected at the end, a plurality of pressure rollers and guide rollers rotatably connected to the frame for tensioning and pulling the upper filter belt and the lower filter belt, the upper filter belt and the lower filter belt are pulled on the frame to form a loading station, a first filter press station, a first water adding station, a second filter press station, a second water adding station, a third filter press station, a discharging station, and a cleaning station which are arranged in sequence; the loading station coats the cement-containing material on the upper surface of the lower filter belt through a feeding mechanism, the upper filter belt and the lower filter belt are in an overlapping state at the first filter press station, the second filter press station and the third filter press station; the upper filter belt and the lower filter belt are in a separated state at the first water adding station and the second water adding station;

[0008] The station also includes a filtrate collection tank and a cleaning liquid collection tank. The cleaning station performs backwashing through a water curtain placed on the upper filter belt and the lower filter belt. The cleaning liquid collection tank collects the cleaning liquid after the upper filter belt and the lower filter belt are cleaned. The filtrate collection tank covers the loading station, the first filter press station, the first water adding station, the second filter press station, the second water adding station and the third filter press station; the cleaning liquid collection tank covers the cleaning station.

[0009] It also includes a water pump, the water inlet of the water pump is connected to the cleaning liquid collection tank, and the water outlet of the water pump is connected to a plurality of nozzles, which are aimed at the middle area of ​​the upper surface of the upper filter belt at the first water adding station and the second water adding station.

[0010] Furthermore, the discharging station includes a plurality of discharging threaded rods, and the discharging threaded rods are close to the upper surface of the upper filter belt and the lower surface of the lower filter belt.

[0011] Furthermore, several pushing screws are provided at the first water adding station and the second water adding station, and the pushing screws are abutted against the upper surface of the lower filter belt. The pushing screws have two thread sections with opposite thread directions. When the pushing screws are pulled and rotated by the lower filter belt, the materials on the lower filter belt can be pushed to both sides of the lower filter belt.

[0012] Furthermore, the feeding mechanism includes a mounting tube and drain tubes connected to both ends of the mounting tube respectively, the mounting tube is communicated with the drain tube, the mounting tube has a notch, a plurality of coating screws are rotatably connected to the notch, and small mud discharge grooves are provided between adjacent coating screws and between the coating screws and the side edges of the notch;

[0013] The drain cylinder is fixedly connected to the mounting cylinder, the drain cylinder is fixed on the frame, the drain cylinder has a drain hole, and both ends of the drain cylinder are respectively provided with a mud inlet pipe;

[0014] The lower filter belt presses all the coating screws tightly.

[0015] Furthermore, the thread ribs of adjacent coating screws have opposite rotation directions.

[0016] Furthermore, a feeding dragon is rotatably connected in the drain cylinder.

[0017] Furthermore, the distance between adjacent spiral plates of the feeding dragon gradually increases from the outside to the inside.

[0018] The feed hinge hole is driven to rotate by a reduction motor, which controls the material to enter the drain cylinder in an orderly manner and enter the installation cylinder from the two drain cylinders, ensuring that the mixture with more water content has a certain pressure in the drain cylinder before entering the installation cylinder, driving part of the liquid to drain out of the drain cylinder and into the filtrate collection tank.

[0019] Compared with the existing technology, this solution completes the pretreatment of the material in the feeding mechanism, that is, it converts the "suspension" into "mud", most of the liquid is separated in the drain cylinder, and the mud enters the installation cylinder and is coated on the upper surface of the lower filter belt.

[0020] Compared with the existing technology, this solution realizes multiple water washing of the mud material, reduces the "vanadium" content in the mud material, improves the purification yield, and reduces material waste.

[0021] Compared with the existing technology, this solution uses the cleaning liquid of the filter belt to humidify the mud material, while in the existing technology, the cleaning liquid is directly returned to the tank and is not effectively utilized. This not only can remove a small amount of solid material in the cleaning liquid, but also can reduce the amount of water used. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the sodium metavanadate purification system.

[0023] Figure 2 This is a schematic diagram of the mud distribution on the lower filter belt.

[0024] Figure 3 It is a cross-sectional schematic diagram of the discharge mechanism at the installation barrel.

[0025] Figure 4 yes Figure 3 Cross-section view along the AA direction.

[0026] Figure 5 yes Figure 4 Enlarged view of part B in the middle.

[0027] Figure 6 It is a three-dimensional schematic diagram of the feeding mechanism.

[0028] In the figure, 11, upper filter belt; 12, lower filter belt; 2, pressure roller; 3, guide roller; 4, filtrate collection tank; 5, cleaning liquid collection tank; 6, discharge threaded rod; 7, push screw; 81, installation cylinder; 82, drain cylinder; 83, coating screw; 84, mud inlet pipe; 85, feed dragon; a, loading station; b, first filter press station; c, first water adding station; d, second filter press station; e, second water adding station; f, third filter press station; g, discharge station; h, cleaning station. DETAILED DESCRIPTION

[0029] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0030] like Figure 1 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 6 As shown, the sodium metavanadate purification system includes a frame, an upper filter belt 11 connected end to end, and a lower filter belt 12 connected at the end. A plurality of pressure rollers 2 and guide rollers 3 are rotatably connected on the frame to tension and pull the upper filter belt 11. The upper filter belt 11 and the lower filter belt 12 are pulled on the frame to form a loading station a, a first filter press station b, a first water adding station c, a second filter press station d, a second water adding station e, a third filter press station f, a discharge station g, and a cleaning station h arranged in sequence; the loading station a coats the cement-containing material on the upper surface of the lower filter belt 12 through a feeding mechanism, and the upper filter belt 11 and the lower filter belt 12 are in an overlapping state at the first filter press station b, the second filter press station d, and the third filter press station f; the upper filter belt 11 and the lower filter belt 12 are in a separated state at the first water adding station c and the second water adding station e;

[0031] It also includes a filtrate collection tank 4 and a cleaning liquid collection tank 5. The cleaning station h is backwashed by a water curtain placed on the upper filter belt 11 and the lower filter belt 12. The cleaning liquid collection tank 5 collects the cleaning liquid after the upper filter belt 11 and the lower filter belt 12 are cleaned. The filtrate collection tank 4 covers the loading station a, the first filter press station b, the first water addition station c, the second filter press station d, the second water addition station e and the third filter press station f; the cleaning liquid collection tank 5 covers the cleaning station h;

[0032] It also includes a water pump, the water inlet of the water pump is connected to the cleaning liquid collection tank 5, and the water outlet of the water pump is connected to a plurality of nozzles, which are aimed at the middle area of ​​the upper surface of the upper filter belt 11 at the first water adding station c and the second water adding station e.

[0033] The discharging station g includes a plurality of discharging threaded rods 6 , which are attached to the upper surface of the upper filter belt 11 and the lower surface of the lower filter belt 12 .

[0034] A plurality of pushing screws 7 are provided at the first water adding station c and the second water adding station e. The pushing screws 7 are abutted against the upper surface of the lower filter belt 12. The pushing screws 7 have two thread sections with opposite thread directions. When the pushing screws 7 are pulled and rotated by the lower filter belt 12, the materials on the lower filter belt 12 can be pushed to both sides of the lower filter belt 12.

[0035] The feeding mechanism includes a mounting cylinder 81 and a drain cylinder 82 respectively connected to the two ends of the mounting cylinder 81. The mounting cylinder 81 is communicated with the drain cylinder 82. The mounting cylinder 81 has a notch, and a number of paint screws 83 are rotatably connected to the notch. There are small mud discharge grooves between adjacent paint screws 83 and between the paint screws 83 and the sides of the notch; the drain cylinder 82 and the mounting cylinder 81 are fixedly connected, the drain cylinder 82 is fixed on the frame, and there are drain holes on the drain cylinder 82. Mud inlet pipes 84 are respectively provided at both ends of the drain cylinder 82; the lower filter belt 12 presses all the paint screws 83.

[0036] A feeding dragon 85 is rotatably connected in the drain cylinder 82, and the distance between adjacent spiral pieces of the feeding dragon 85 gradually increases from the outside to the inside.

[0037] The feed hinge is driven by a reduction motor to rotate, orderly controlling the material to enter the drain barrel 82 and then enter the installation barrel 81 from the two drain barrels 82. This ensures that the mixed material with a high water content has a certain pressure in the drain barrel 82 before entering the installation barrel 81, driving some liquid to drain out of the drain barrel 82 and into the filtrate sump 4. Before humidifying the dehydrated mud, the mud on the lower filter belt 12 is pushed to the blank areas on both sides of the lower filter belt 12.

[0038] Detailed introduction to the operation process and purpose of each workstation:

[0039] Loading Station a: After draining, the material is coated on the lower filter belt 12. Coating is achieved by rotating the coating screws 83, which are pulled by the lower filter belt 12. Since the threaded ribs of adjacent coating screws 83 rotate in opposite directions, the distribution of the sludge on the lower filter belt 12 can be monitored during the loading process. After entering the drain drum 82, the water content of the material with a high water content is partially filtered out through the lower filter plates. As the pitch of the spiral blades of the feed dragon 85 gradually decreases, the water pressure in the drain drum 82 increases as it approaches the mounting drum 81, achieving pressurized drainage, significantly reducing the moisture content of the material and resulting in a thin, sludge-like consistency. The material then enters the mounting drum 81, which is fixed to the frame. This ensures that the lower filter belt 12 maintains contact with all coating screws 83, driving them to rotate and discharging the sludge onto the lower filter belt 12.

[0040] The first filter press station b, the second filter press station d, and the third filter press station f: through the up and down traction of the pressure roller 2 and the guide roller 3, in the tensioned state, the upper filter belt 11 and the lower filter belt 12 continuously press the mud in the overlapping state to achieve pressure filtration and water removal.

[0041] The first water adding station c and the second water adding station e: At this time, the upper filter belt 11 and the lower filter belt 12 are in a separated state, and most of the mud is distributed on the lower filter belt 12. The lower filter belt 12 drives the pushing screw 7 to rotate, and spreads the mud to both sides of the lower filter belt 12, making room for water to dissolve. In the process of overlapping the lower filter belt 12 and the upper filter belt 11 again, the mud and water are squeezed and mixed with each other. In the subsequent filter pressing process, water is squeezed out to achieve "water washing" of the mud, and the "vanadium"-containing substances in the mud are further filtered out.

[0042] Discharge station g: The filtration before discharge is more thorough than that before humidification. The number of pressing rollers 2 in this section can be increased. After the last filtration, the mud is dehydrated more thoroughly and contains very little "vanadium". The discharge threaded rod 6 is driven by the lower filter belt 12 and the upper filter belt 11 to rotate, so that the mud residue is discharged from one side and collected.

[0043] Cleaning station h: When cleaning the upper filter belt 11 and the lower filter belt 12, a water curtain can be used. On the one hand, it can reduce water consumption, and on the other hand, it can expand the cleaning range. It can basically cover the entire horizontal section of the crawler, play a certain deodorizing effect, and reduce the odor in the workshop; the cleaning liquid produced after cleaning can be partially used for humidifying the mud.

[0044] The sodium metavanadate purification process involved includes the following steps:

[0045] A. The sodium metavanadate-containing mud material after the drainage treatment is coated on the lower filter belt 12 through the feeding mechanism; B. After completing the first filter press dehydration at the first filter press station b, the mud material after the first dehydration is humidified with part of the cleaning liquid generated by cleaning the upper filter belt 11 and the lower filter belt 12 at the first water adding station; C. Then, a second filter press dehydration is completed at the second filter press station d, and the mud material after the second dehydration is again watered with part of the cleaning liquid generated by cleaning the upper filter belt 11 and the lower filter belt 12 at the second water adding station; D. After the second humidification, the last filter press dehydration is carried out at the second filter press station d; E. The filter residue adhering to the upper surface of the upper filter belt 11 and the lower surface of the lower filter belt 12 after the final dehydration is removed and collected at the unloading station; F. The remaining cleaning liquid is filtered through the upper filter belt 11 before the feeding station a, mixed with the filtrate produced by the filter press, and ammonium chloride is added for vanadium precipitation treatment.

[0046] In step A, the water content of the mud used for coating the upper surface of the lower filter belt 12 is 120-200%; in steps B and C, the water content of the mud after humidification is between 90-120%; in step D, the water content of the mud after the final dehydration is less than 80%.

[0047] like Figure 2 As shown, this solution adopts a method of gradually widening the distribution range of the mud material to achieve humidification of the mud material when the filter belt is in a tensioned state. The width of the upper filter belt 11 and the lower filter belt 12 are the same. Taking its width of 2.5 meters as an example, when feeding, the mud material distribution width can be controlled at about 1.5 meters. After one humidification and horizontal pushing of the material, the mud material distribution width can be controlled at about 1.9 meters. After the second humidification and horizontal pushing of the material, the mud material distribution width on the lower filter belt 12 can be controlled at about 2.3 meters. A certain amount of free area is reserved on both sides of the lower filter belt 12 to avoid mud overflow.

[0048] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A sodium metavanadate efficient purification system, characterized in that: The invention comprises a frame, an upper filter belt (11) connected at the head and tail, and a lower filter belt (12) connected at the tail, a plurality of pressing rollers (2) and a guide roller (3) are rotatably connected on the frame to tension and pull the upper filter belt (11) and the lower filter belt (12), and the upper filter belt (11) and the lower filter belt (12) are pulled on the frame to form a feeding station (a), a first filter pressing station (b), a first water adding station (c), a second filter pressing station (d), a second water adding station (e), a third filter pressing station (f), and the like. Filtering station (f), discharging station (g), cleaning station (h); the loading station (a) coats cement-containing material on the upper surface of the lower filter belt (12) through a feeding mechanism, and the upper filter belt (11) and the lower filter belt (12) are in an overlapping state at the first filter pressing station (b), the second filter pressing station (d), and the third filter pressing station (f); the upper filter belt (11) and the lower filter belt (12) are in a separated state at the first water adding station (c) and the second water adding station (e); The filter further comprises a filtrate collecting tank (4) and a cleaning liquid collecting tank (5); the cleaning station (h) is backwashed by a water curtain placed on the upper filter belt (11) and the lower filter belt (12); the cleaning liquid collecting tank (5) collects the cleaning liquid after the upper filter belt (11) and the lower filter belt (12) are cleaned; the filtrate collecting tank (4) covers the feeding station (a), the first filter pressing station (b), the first water adding station (c), the second filter pressing station (d), the second water adding station (e) and the third filter pressing station (f); the cleaning liquid collecting tank (5) covers the cleaning station (h); It also includes a water pump, the water inlet of the water pump is connected to the cleaning liquid collecting tank (5), and the water outlet of the water pump is connected to a plurality of nozzles, and the nozzles are aimed at the middle area of ​​the upper surface of the upper filter belt (11) at the first water adding station (c) and the second water adding station (e).

2. A sodium metavanadate efficient purification system according to claim 1, characterized in that, The discharging station (g) comprises a plurality of discharging threaded rods (6), which are attached to the upper surface of the upper filter belt (11) and the lower surface of the lower filter belt (12).

3. A sodium metavanadate efficient purification system according to claim 1, characterized in that, A plurality of pushing screws (7) are provided at both the first water adding station (c) and the second water adding station (e). The pushing screws (7) are abutted against the upper surface of the lower filter belt (12). The pushing screws (7) have two thread sections with opposite thread directions. When the pushing screws (7) are pulled and rotated by the lower filter belt (12), the materials on the lower filter belt (12) can be pushed to both sides of the lower filter belt (12).

4. A sodium metavanadate efficient purification system according to claim 1, 2 or 3, characterized in that: The feeding mechanism comprises a mounting cylinder (81) and drain cylinders (82) respectively connected to both ends of the mounting cylinder (81); the mounting cylinder (81) and the drain cylinder (82) are in communication; the mounting cylinder (81) has a notch, and a plurality of coating screws (83) are rotatably connected to the notch; small mud discharge grooves are provided between adjacent coating screws (83) and between the coating screws (83) and the sides of the notch; The drain cylinder (82) and the mounting cylinder (81) are fixedly connected, the drain cylinder (82) is fixed on the frame, the drain cylinder (82) has a drain hole, and mud inlet pipes (84) are respectively provided at both ends of the drain cylinder (82); The lower filter belt (12) compresses all the coating screws (83).

5. A sodium metavanadate efficient purification system according to claim 4, characterized in that: The thread ribs of adjacent coating screws (83) rotate in opposite directions.

6. A sodium metavanadate efficient purification system according to claim 4, characterized in that: A feeding dragon (85) is rotatably connected in the drain cylinder (82).

7. A sodium metavanadate efficient purification system according to claim 4, characterized in that: The distance between adjacent spiral plates of the feeding dragon (85) increases gradually from the outside to the inside.

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