Cold water adding device of vacuum flat plate filter

Abstract

The utility model relates to the technical field of mineral filtration, and discloses a cold water adding device of a vacuum flat plate filter. The vacuum flat disc filter comprises a central platform and a circular filter disc, and the filter disc is provided with a distributor, a first weak filtrate scrubber, a second weak filtrate scrubber, a hot water scrubber, a multi-head discharging screw conveyor and a back flushing device. The cold water adding device comprises a water supply assembly, a cold water spraying assembly and a supporting assembly, the supporting assembly comprises a first support and a second support, the first support and the second support are adjustable in height, and the spraying assembly is erected between the distributing device and a weak filtrate washer. According to the device, before aluminum hydroxide slurry enters a weak filtrate scrubber, dynamic flushing is carried out, organic matters and impurities are rapidly flushed, particle adhesion is avoided, the filter cloth blocking risk is reduced, and the service life of the filter cloth is greatly prolonged. Impurities entering follow-up procedures can be reduced from the source, air permeability of filter cloth is maintained, washing water smoothly penetrates through the filter cloth, filter liquor is prevented from being mixed, and washing efficiency and aluminum hydroxide product quality are improved.

Description

Technical Field

[0001] This utility model relates to the field of mineral filtration technology, specifically a cold water addition device for a vacuum disc filter. Background Technology

[0002] In existing alumina production methods, bauxite is processed using the Bayer process to produce aluminum hydroxide slurry. The aluminum hydroxide slurry is pumped to a vacuum disc filter distributor, where it is evenly distributed. The slurry then passes through a first weak filtrate, a second weak filtrate, and hot water washing. After drying, the aluminum hydroxide is conveyed by a multi-head unloading screw conveyor to a belt conveyor, which then sends it to a boiler for calcination to obtain alumina.

[0003] In the daily production of alumina, due to limitations in ore quality, some ores contain a significant amount of impurities. During the washing process using a vacuum disc filter, this can easily cause filter cloth clogging and cross-contamination of the filtrate, affecting the lifespan of the filter cloth and reducing the filter's capacity and washing efficiency. Furthermore, the produced aluminum hydroxide contains more impurities and is of lower quality.

[0004] Therefore, how to effectively rinse organic matter and impurities in aluminum hydroxide slurry to prevent them from entering the first weak filtrate zone, the second weak filtrate zone, and the hot water washing zone, causing the filter cloth in the corresponding areas to harden and become clogged, and thus leading to cross-contamination of filtrate, is one of the problems that urgently need to be solved in this field. Utility Model Content

[0005] To overcome the problems existing in related technologies, this utility model provides a cold water adding device for a vacuum disc filter. This device dynamically washes away organic matter and impurities on the surface of aluminum hydroxide, preventing aluminum hydroxide particles from sticking together and hardening, thus avoiding clogging the filter cloth and reducing its air permeability. This effectively solves the problems of filter cloth hardening and clogging, as well as filtrate cross-contamination, improving washing efficiency and extending the service life of the filter cloth.

[0006] The technical solution adopted by this utility model is: a cold water addition device for a vacuum flat plate filter, wherein the vacuum flat plate filter includes a horizontally placed central platform, and the central platform is surrounded by a circular filter disc assembled from several fan-shaped filter plates.

[0007] The upper surface of the circular filter disc is equipped with a feeder, a cold water adding device, a first weak filtrate washer, a second weak filtrate washer, a hot water washer, a multi-head unloading screw conveyor, and a backflushing device.

[0008] The cold water adding device includes a water supply component, a cold water spraying component, and a support component. The support component includes a first bracket and a second bracket, which support the cold water spraying component mounted on a circular filter plate between the fabric spreader and the weak filtrate washer.

[0009] Furthermore, the cold water spray assembly includes a main spray pipe, a branch spray pipe, and a nozzle. The main spray pipe has a first water outlet spaced axially on both sides. The first water outlet has a threaded structure embedded in it. One end of the branch spray pipe is threadedly connected to the first water outlet, and the other end is equipped with the nozzle.

[0010] Furthermore, the end of the spray branch pipe where the nozzle is installed extends horizontally a certain distance away from the main spray pipe, and then extends downward a certain distance so that the nozzle is directly facing the surface of the circular filter disc.

[0011] Furthermore, the distance that extends horizontally from the spray branch pipe where the nozzle is installed along the direction away from the main spray pipe increases radially outward from the central platform relative to the circular filter disc.

[0012] Furthermore, the first support is located on the central platform, and the second support is installed on the factory floor.

[0013] Furthermore, both the first and second supports include a flange base, a support body, a height adjustment mechanism, and a U-shaped clamp. The support body includes two vertical columns and a horizontal bar. The two vertical columns are spaced apart, and each has the flange base at its bottom. The two ends of the horizontal bar are fixedly connected to the tops of the two vertical columns, respectively. A through hole with internal threads is provided in the middle of the horizontal bar. The height adjustment mechanism includes a lead screw with external threads on its body. One end of the lead screw has a manual knob, and the other end of the lead screw passes through the through hole and is fixedly connected to the bottom of the U-shaped clamp. The U-shaped opening of the U-shaped clamp locks and supports the main sprinkler pipe.

[0014] Furthermore, the water supply assembly includes a delivery pump, a water supply pipe, and a regulating valve. The regulating valve is installed in the body of the water supply pipe. One end of the water supply pipe is connected to the main sprinkler pipe, and the other end is connected to the outlet of the delivery pump.

[0015] Furthermore, the nozzle is a conical nozzle made of 316 stainless steel.

[0016] This utility model's cold water addition device for a vacuum disc filter has the following technical advantages: The cold water spray assembly of this device is installed between the cloth feeder and a weak filtrate washer, dynamically rinsing the aluminum hydroxide slurry before it enters the weak filtrate washer. Through cold water rinsing, organic matter and impurities on the surface of the aluminum hydroxide can be quickly washed away, preventing organic matter from adhering to the surface of the aluminum hydroxide particles and hardening, thus reducing the risk of filter cloth clogging. Compared to filters without this device, the frequency of filter cloth clogging due to organic matter is significantly reduced, effectively extending the service life of the filter cloth. This device reduces impurities entering subsequent processes at the source, maintaining the normal air permeability of the filter cloth and ensuring that washing water can smoothly pass through the filter cloth in subsequent processes, achieving thorough washing of the aluminum hydroxide and greatly improving washing efficiency. Through effective rinsing of the aluminum hydroxide slurry, organic matter and impurities are removed, effectively reducing the impurity content in the aluminum hydroxide, improving its purity, and meeting higher product quality requirements.

[0017] Other features and advantages disclosed in this utility model will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0019] Figure 1 This is a schematic diagram illustrating a cold water adding device and installation structure for a vacuum disc filter according to an exemplary embodiment.

[0020] Figure 2 This is a schematic diagram illustrating another vacuum disc filter cold water adding device and its installation structure according to an exemplary embodiment.

[0021] Figure 3 This is a schematic diagram of the overall structure of a cold water addition device for a vacuum disc filter according to an exemplary embodiment.

[0022] Figure 4 This is a schematic diagram of the support component structure of a cold water addition device for a vacuum disc filter according to an exemplary embodiment.

[0023] Reference numerals: 10. Cold water adding device for vacuum disc filter; 20. Central platform; 30. Circular filter disc; 31. Fan-shaped filter plate; 40. Distributor; 50. Cold water adding device; 51. Water supply assembly; 511. Conveyor pump; 512. Water supply pipe; 513. Regulating valve; 52. Cold water spray assembly; 521. Main spray pipe; 522. Branch spray pipe; 523. Nozzle; 53. Support assembly; 531. First support; 532. Second support; 533. Flange base; 534. Support body; 5341. Vertical column; 5342. Crossbar; 535. Height adjustment mechanism; 5351. Screw; 5352. Manual knob; 536. U-shaped clamp; 60. First weak filtrate washer; 70. Second weak filtrate washer; 80. Hot water washer; 90. Multi-head unloading screw conveyor; 100. Backflushing device. Detailed Implementation

[0024] The specific embodiments disclosed herein will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this disclosure.

[0025] like Figure 1 , Figure 3 The image shows a disclosed exemplary embodiment of the present invention. The present invention relates to a cold water adding device 10 for a vacuum disc filter, which is applied to a vacuum disc filter. The vacuum disc filter includes a horizontally placed central platform 20, around which a circular filter disc 30, composed of several fan-shaped filter plates 31, is arranged. The upper surface of the circular filter disc 30 is supported by a distributor 40, a cold water adding device 50, a primary weak filtrate washer 60, a secondary weak filtrate washer 70, a hot water washer 80, a multi-head unloading screw conveyor 90, and a backflushing device 100. The cold water adding device 50 includes a water supply assembly 51, a cold water spray assembly 52, and a support assembly 53. The support assembly 53 includes a first bracket 531 and a second bracket 532, which support the cold water spray assembly 52 mounted on the surface of the circular filter disc 30 between the distributor 40 and the primary weak filtrate washer 60.

[0026] A rotary table drive device is provided at the bottom of the circular filter disc 30, driving the circular filter disc 30 to rotate relative to the central platform 20. Each sector-shaped filter plate 31 is an independent cavity connected to a vacuum pipe, and its surface is a perforated filter plate that supports the filter cloth. During normal production, the circular filter disc 30 rotates counterclockwise in a horizontal position, creating a certain vacuum inside the filter cavity. High-alkali, high-solids aluminum hydroxide slurry is pumped to the disc surface. Upon reaching the disc surface, the slurry first undergoes solid-liquid separation due to the vacuum. The liquid portion of the slurry is sucked away to become the mother liquor, which is then sent to the evaporator for concentration and used in the raw material process for ore blending. The solidified portion (aluminum hydroxide) in the slurry is retained by the filter medium to form a filter cake. As the circular filter disc 30 rotates, the filter cake enters a weak filtrate zone, where it undergoes preliminary washing with a weak filtrate containing a certain alkali concentration. After the first washing, the alkali concentration in the washing liquid further increases, becoming a strong filtrate sent to the red mud washing system. The filter cake after the first washing continues to enter the second weak filtrate zone with the circular filter disc 30 for a second washing. The filtrate after the second wash is a weak filtrate with a certain alkali concentration, which is returned to the process flow as the washing solution for the first wash. After being washed twice with the weak filtrate, the filter cake enters the hot water washing zone for a final wash, and then enters the drying zone. The dried filter cake is discharged from the circular filter disc 30 by the multi-head unloading screw conveyor 90 and sent to the calcination process to produce the finished alumina. After unloading, the filter cloth of the circular filter disc 30 and the residual filter cake are loosened by the back-blowing air and enter the next production cycle.

[0027] When aluminum hydroxide slurry containing a large amount of organic matter and impurities enters the first weak filtrate zone after being washed by the first weak filtrate washer 60, the organic matter and impurities adhering to the surface of the aluminum hydroxide cause the aluminum hydroxide particles to stick together and harden, which in turn causes the filter cloth to harden and become clogged, reducing the air permeability of the filter cloth. If the filtrate on the filter cake is not completely discharged in time, as the circular filter disc 30 continues to rotate, the first weak filtrate will enter the second weak filtrate zone, resulting in filtrate cross-contamination.

[0028] The cold water spray assembly 52 of the cold water addition device 10 of this invention's vacuum flat plate filter is installed between the cloth feeder 40 and a weak filtrate washer 60. It dynamically washes the aluminum hydroxide slurry before it enters the weak filtrate washer 60, reducing impurities on the aluminum hydroxide surface. The washed filtrate is isolated and removed, preventing it from re-entering the production system and reducing the circulation of impurities in the aluminum hydroxide. Simultaneously, it prevents organic matter from adhering to the surface of the aluminum hydroxide particles, causing them to stick and harden, thus reducing the risk of filter cloth clogging. Compared to filters without this device, the frequency of filter cloth clogging due to organic matter is significantly reduced, effectively extending the service life of the filter cloth. This device reduces impurities entering subsequent processes at the source, maintains the normal air permeability of the filter cloth, and ensures that washing water can smoothly pass through the filter cloth in subsequent processes, achieving thorough washing of the aluminum hydroxide and greatly improving washing efficiency. Through effective washing of the aluminum hydroxide slurry, organic matter and impurities are removed, effectively reducing the impurity content in the aluminum hydroxide, improving its purity, and meeting higher product quality requirements.

[0029] For example, such as Figure 1 , Figure 3 As shown in the exemplary embodiment disclosed in this utility model, the cold water spray assembly 52 includes a main spray pipe 521, a branch spray pipe 522, and a nozzle 523. The main spray pipe 521 has first water outlets spaced axially on both sides of its body, each with an embedded threaded structure. One end of the branch spray pipe 522 is threadedly connected to the first water outlet, and the other end is fitted with a nozzle 523. The end of the branch spray pipe 522 with the nozzle 523 extends horizontally a distance away from the main spray pipe 521, and then extends downwards a distance so that the nozzle 523 faces the surface of the circular filter disc 30. The nozzle 523 is a conical nozzle made of 316 stainless steel.

[0030] The main spray pipe 521 has alternating first water outlets on both sides along the axial direction, with spray branch pipes 522 installed on them. This allows cold water to be evenly distributed on the fan-shaped filter plate 31, avoiding blind spots in the rinsing process. The first water outlets on both sides of the main spray pipe 521 adopt an embedded threaded structure, which is threadedly connected to the spray branch pipes 522, simplifying the installation process and allowing for quick disassembly and replacement of the spray branch pipes 522 during later maintenance. At the same time, the number and installation position of the spray branch pipes 522 can be flexibly adjusted according to the actual size of the filter plate and production needs, so as to make the rinsing coverage more comprehensive and adapt to different working conditions. The spray branch pipe 522 is equipped with nozzles 523, which extend horizontally and then downwards, so that the nozzles 523 are directly facing the surface of the circular filter plate 30. This ensures that the cold water can be sprayed vertically onto the surface of the aluminum hydroxide slurry on the filter plate, enhancing the rinsing force, improving the rinsing effect, and more effectively removing organic matter and impurities from the slurry. 316 stainless steel conical nozzles 523 have excellent corrosion resistance, resisting the erosion of acid and alkali substances during the filtration process, reducing damage and replacement frequency caused by corrosion, and lowering equipment maintenance costs.

[0031] For example, such as Figure 2 As shown, in another exemplary embodiment of this invention, the distance at which the nozzle 523 is installed on the end of the spray branch pipe 522 extends horizontally away from the spray main pipe 521 increases radially outward from the central platform 20 relative to the circular filter disc 30. The circular filter disc 30 of the vacuum disc filter is assembled from fan-shaped filter plates 31. The distance at which the nozzle 523 is installed on the end of the spray branch pipe 522 extends horizontally away from the spray main pipe 521 increases radially outward from the central platform 20 relative to the circular filter disc 30. This causes the spray branch pipe 522 to naturally form a fan-shaped surface, perfectly fitting the structure of the fan-shaped filter plates 31 of the filter disc. Compared to the traditional linear layout, this design effectively avoids rinsing blind spots at the edges and corners of the filter disc, ensuring that the entire surface of the fan-shaped filter plates 31, especially the joints, receives uniform and thorough rinsing, thus comprehensively improving the rinsing effect.

[0032] For example, such as Figure 3 and 4 As shown, in an exemplary embodiment disclosed in this utility model, the first bracket 531 is disposed on the central platform 20, and the second bracket 532 is installed on the factory floor. Both the first support 531 and the second support 532 include a flange base 533, a support body 534, a height adjustment mechanism 535, and a U-shaped clamp 536. The support body 534 includes two vertical columns 5341 and a horizontal bar 5342. The two vertical columns 5341 are spaced apart, and each of them has a flange base 533 at its bottom. The two ends of the horizontal bar 5342 are fixedly connected to the tops of the two vertical columns 5341 respectively. A through hole with internal threads is opened in the middle of the horizontal bar 5342. The height adjustment mechanism 535 includes a screw 5351 with external threads on its body. One end of the screw 5351 is equipped with a manual knob 5352. The other end of the screw 5351 passes through the through hole and is fixedly connected to the bottom of the U-shaped clamp 536. The U-shaped opening of the U-shaped clamp 536 locks and supports the main sprinkler pipe 521.

[0033] When the vacuum disc filter is working, its circular filter disc 30 rotates relative to the central platform 20 and the ground. By placing the first bracket 531 on the central platform 20 and the second bracket 532 on the factory floor, the spray main pipe 521, supported by the first and second brackets 531 and 532, can rotate relative to the circular filter disc 30. The bracket body 534 consists of two vertical columns 5341 and a horizontal bar 5342, forming a stable "gate"-shaped structure. Both vertical columns 5341 have flange bases 533 at their bottoms, which are bolted to the central platform 20 or the factory floor, ensuring that the spray main pipe 521 will not shift due to vibration or external force during operation, thus guaranteeing the stability and continuity of the rinsing operation. The height adjustment mechanism 535 uses a screw 5351 with an internal threaded through hole; simply rotating the manual knob easily moves the screw 5351 up and down, thereby adjusting the height of the U-shaped clamp and the spray main pipe 521. The U-shaped opening of the U-shaped clamp can tightly hold the spray pipe 521, providing reliable support for the spray pipe 521 and avoiding uneven rinsing caused by shaking, thus improving the rinsing effect. The U-shaped clamp has a simple structure and is very convenient to install and disassemble. When installing the spray pipe 521, simply clamp the spray pipe 521 with the U-shaped clamp, and then rotate the manual knob 5352 of the first bracket 531 and the second bracket 532 screw 5351 to adjust the installation height of the spray pipe 521 so that it is mounted on the surface of the circular filter disc 30.

[0034] For example, such as Figure 3As shown in the exemplary embodiment disclosed in this utility model, the water supply component 51 includes a delivery pump 511, a water supply pipe 512, and a regulating valve 513. The regulating valve 513 is provided on the pipe body of the water supply pipe 512. One end of the water supply pipe 512 is connected to the main spray pipe 521, and the other end is connected to the outlet of the delivery pump 511. The delivery pump 511 serves as the power source for the water supply component 51, providing continuous and stable water pressure for the entire cold water spray system. The connection between one end of the water supply pipe 512 and the outlet of the delivery pump 511 forms a stable and smooth water supply path. The regulating valve 513 on the pipe body of the water supply pipe 512 allows operators to flexibly adjust the cold water flow rate. In actual production, based on the thickness of the material on the filter disc, the impurity content, and feedback on the rinsing effect, operators can control the flow rate of cold water entering the main spray pipe 521 through the regulating valve 513.

[0035] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0036] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0037] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A cold water adding device for a vacuum disc filter, characterized in that, The vacuum disc filter includes a horizontally placed central platform, and the central platform is surrounded by a circular filter disc composed of several fan-shaped filter plates. The upper surface of the circular filter disc is equipped with a feeder, a cold water adding device, a first weak filtrate washer, a second weak filtrate washer, a hot water washer, a multi-head unloading screw conveyor, and a backflushing device. The cold water adding device includes a water supply component, a cold water spraying component, and a support component. The support component includes a first bracket and a second bracket, which support the cold water spraying component mounted on a circular filter plate between the fabric spreader and the weak filtrate washer.

2. The cold water adding device for the vacuum disc filter according to claim 1, characterized in that, The cold water spray assembly includes a main spray pipe, a branch spray pipe, and a nozzle. The main spray pipe has a first water outlet spaced axially on both sides. The first water outlet has a threaded structure embedded in it. One end of the branch spray pipe is threadedly connected to the first water outlet, and the other end is equipped with the nozzle.

3. The cold water adding device for the vacuum disc filter according to claim 2, characterized in that, The end of the spray branch pipe with the nozzle installed extends horizontally a certain distance away from the main spray pipe, and then extends downward a certain distance so that the nozzle is directly facing the surface of the circular filter disc.

4. The cold water adding device for the vacuum disc filter according to claim 3, characterized in that, The distance at the end of the spray branch pipe where the nozzle is installed extends horizontally away from the main spray pipe, and increases radially outward from the central platform relative to the circular filter disc.

5. The cold water adding device for the vacuum disc filter according to claim 2, characterized in that, The first support is located on the central platform, and the second support is installed on the factory floor.

6. The cold water adding device for the vacuum disc filter according to claim 2, characterized in that, Both the first and second supports include a flange base, a support body, a height adjustment mechanism, and a U-shaped clamp. The support body includes two vertical columns and a horizontal bar. The two vertical columns are spaced apart, and each has the flange base at its bottom. The two ends of the horizontal bar are fixedly connected to the tops of the two vertical columns, respectively. A through hole with internal threads is opened in the middle of the horizontal bar. The height adjustment mechanism includes a lead screw with external threads on its body. One end of the lead screw has a manual knob, and the other end of the lead screw passes through the through hole and is fixedly connected to the bottom of the U-shaped clamp. The U-shaped opening of the U-shaped clamp locks and supports the main sprinkler pipe.

7. The cold water adding device for the vacuum disc filter according to claim 2, characterized in that, The water supply assembly includes a delivery pump, a water supply pipe, and a regulating valve. The regulating valve is installed in the body of the water supply pipe. One end of the water supply pipe is connected to the main sprinkler pipe, and the other end is connected to the outlet of the delivery pump.

8. The cold water adding device for the vacuum disc filter according to claim 2, characterized in that, The nozzle is a conical nozzle made of 316 stainless steel.

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