Mother liquor advanced treatment system in aluminum oxide production process

Abstract

The invention provides a mother liquor deep treatment system in an aluminum oxide production process, and relates to the technical field of aluminum oxide mother liquor treatment. An axial flow blade is rotatably arranged at the bottom of the upper tank body, a filtering device is arranged on the side portion of the upper tank body, a base is included, a circulating sliding rail is arranged on the base, a plurality of filtering mechanisms are arranged in the circulating sliding rail in a sliding mode, a first lower tank body and a second lower tank body are arranged on the lower portion of the filtering device, and a fine filter screen and a turbidity sensor are arranged in the first lower tank body. The circulating sliding rails on the upper portions of the first lower pool body and the second lower pool body are vertically arranged and spaced in the horizontal direction, the two ends of the circulating sliding rails above the first lower pool body and the second lower pool body are encircled, the filtering mechanism slides in the circulating sliding rails in a one-way mode, an air box communicated with an air source is arranged on the side portion of the circulating sliding rail above the second lower pool body, and a plurality of air holes are formed in the air box. The filtering mechanism comprises a sliding seat in sliding connection with the circulating sliding rail, and a filtering assembly is arranged on the sliding seat. After impurities are filtered, the impurities are separated from the filter screen immediately, and the passing ability of the filter screen is kept.

Description

Technical Field

[0001] The invention relates to the technical field of alumina mother liquor treatment, and in particular to a mother liquor deep treatment system in an alumina production process. Background Art

[0002] Alumina is an inorganic substance with the chemical formula Al 2 O 3 It is a high hardness compound with a melting point of 2054℃ and a boiling point of 2980℃. It is an ionic crystal that can be ionized at high temperatures. It is often used to make refractory materials. It is also called alumina in mining, ceramics and materials science. The Bayer process is a chemical process widely used in industry to produce alumina from bauxite.

[0003] In the prior art, when the mother liquor in the production of alumina is coarsely filtered, the impurities filtered out need to be regularly cleaned from the filter structure, and then the impurities are processed to prevent the impurities from adhering to the filter structure, affecting the permeability of the filter structure and thus affecting the filtering effect and filtering efficiency. At present, as the filtering proceeds, impurities gradually accumulate on the filter structure. Before the next cleaning of impurities, the impurities gradually accumulated on the filter structure will affect its permeability, causing the filter structure to be in a low permeability state during part of the working time, and the filtering efficiency and filtering effect are affected. Summary of the invention

[0004] The purpose of the present invention is to develop a system for deep treatment of mother liquor in the production process of alumina, which can separate impurities from the filter screen immediately after filtering the impurities and maintain the permeability of the filter screen.

[0005] The present invention is achieved through the following technical solutions:

[0006] A system for deep treatment of mother liquor in an alumina production process, comprising:

[0007] Upper pool body;

[0008] Axial flow blades are rotatably arranged at the bottom of the upper tank body;

[0009] The filtering device is arranged on the side of the upper pool body and comprises:

[0010] Pedestal;

[0011] A circulating slide rail is arranged on the base;

[0012] Multiple filtering mechanisms are slidably arranged in a circulating slide rail;

[0013] The first lower tank body and the second lower tank body are arranged at the lower part of the filtering device;

[0014] A fine filter is provided in the first lower tank body;

[0015] A turbidity sensor is arranged on the inner wall of the first lower tank body at the side of the top surface of the fine filter;

[0016] The circulating rails on the upper parts of the first lower tank body and the second lower tank body are arranged vertically, and there is a gap between the circulating rails above the first lower tank body and the second lower tank body in the horizontal direction. The two ends of the circulating rails above the first lower tank body and the second lower tank body are respectively enclosed at the top and bottom of the base, and the filtering mechanism slides unidirectionally in the circulating rails;

[0017] An air box connected to an air source is provided on the side of the circulation slide rail above the second lower pool body, and a plurality of air holes are provided on the air box;

[0018] The filtering mechanism comprises a sliding seat slidably connected to the circulating slide rail, a filtering assembly is arranged on the sliding seat, and the filtering assembly comprises a filter frame connected to the sliding seat, and a filter screen is arranged in the filter frame.

[0019] Optionally, the circulating slide rail includes a filtering section, a first horizontal section, a lower rotating section, a discharging section, a second horizontal section, and an upper rotating section which are connected in sequence, and the upper rotating section is connected to the filtering section;

[0020] The filter section is vertically arranged on the side wall of the base close to the upper pool body, the first horizontal section connected to the bottom end of the filter section is horizontally arranged and extends in the direction away from the upper pool body, the end of the first horizontal section away from the upper pool body is connected to the lower rotating section, the lower rotating section extends along the bottom of the base to the side wall of the base away from the upper pool body, the discharge section connected to the end of the lower rotating section is vertically arranged upward on the side wall of the base, the second horizontal section connected to the top end of the discharge section is horizontally arranged and extends in the direction close to the upper pool body, the end of the second horizontal section away from the discharge section is at the back of the filter section, the upper rotating section is arranged at the top of the base and its two ends are respectively connected to the filter section and the second horizontal section, the first lower pool body is below the filter section, and the second lower pool body is below the discharge section.

[0021] Optionally, several adjacent filter mechanisms in the circulating slide rail are the same filter unit, the filter section can accommodate at least three filter units, and the mesh size of the filter screen of the multiple filter mechanisms in the same filter unit gradually decreases in the sliding direction of the filter mechanism in the circulating track.

[0022] Optionally, an overflow port is provided at the top of the upper pool body on the side of the filter section, and the position of the overflow port is higher than the top of the filter section. Vertically arranged filter baffles are provided on the bases on both sides of the filter section, and the filter baffles are connected to the side walls of the lower part of the overflow port of the upper pool body. The two ends of the filter frame are in sliding contact with the inner walls of the two filter baffles in the filter section, and the end of the filter frame away from the slide seat is in sliding contact with the side wall of the upper pool body in the filter section.

[0023] Optionally, two connecting blocks are provided at the end of the filter frame close to the slide seat, the two connecting blocks are hinged to the two ends of the slide seat, and the slide seat is provided with a limiting boss that cooperates with the filter frame;

[0024] The limiting boss is inclined in the filtering section and is located at the bottom of the filter frame, and the end of the limiting boss away from the base is the higher end.

[0025] Optionally, the outer edge of the filter frame between the two connecting blocks is in the shape of a concave arc surface, the axis of rotation of the connecting block is coaxial with the concave arc surface of the outer edge of the filter frame, the side wall of the sliding seat close to the filter frame is in the shape of an arc surface adapted to the shape of the outer edge of the filter frame, and a torsion spring is provided between the sliding seat and the connecting block.

[0026] Optionally, an inclined support rod is provided inside the slide seat, and a sliding ball is provided at the end of the support rod away from the slide seat, and the outer diameter of the sliding ball is larger than the support rod;

[0027] The circulating slide rail comprises, from outside to inside, an outer slide rail whose shape matches the support rod and an inner slide rail whose shape matches the slide ball. The support rod slides in the outer slide rail, and the slide ball slides in the inner slide rail. Two adjacent slide balls are connected with a pull rope.

[0028] Optionally, a wheel groove is provided in the base inside the connection point between the filtering section and the first horizontal section and the connection point between the discharging section and the second horizontal section, a guide wheel is rotatably provided in the wheel groove, the guide wheel is adapted to the position of the inner slide rail of the circulating slide rail, and a groove is provided on the inner wall of the inner slide rail at the side of the guide wheel, and the wheel groove is connected to the inner slide rail through the groove;

[0029] The guide wheel is evenly provided with a plurality of quadrangular pyramid-shaped blocks, which are adapted to the gap between two adjacent filter mechanism sliding balls. The blocks can slide into the inner slide rail through the slots. The guide wheel and the sliding balls operate synchronously, and a motor for driving the guide wheel to rotate is provided in the inner base of the guide wheel.

[0030] Optionally, two unloading baffles parallel to each other are vertically provided on the side walls of the base on both sides of the unloading section, and a guide plate is also connected between the ends of the two unloading baffles away from the base. A plurality of spherical crown-shaped baffles arranged vertically and evenly spaced are provided on the inner walls of the two unloading baffles, and the baffles are located on the sliding track of the lower end of the filter frame of the filter mechanism in the unloading section.

[0031] Optionally, box grooves are provided on the bases on both sides of the unloading section, the box grooves are located inside the two unloading baffles, the air box is arranged in the box grooves, the thickness of the air box is adapted to the box grooves, and the outer surface of the air box is flush with the surface of the base;

[0032] The interior of the air box is a cavity structure, and a plurality of partitions are arranged inside the air box. The plurality of partitions divide the air box into a plurality of independent air cavities, each of the air cavities is connected to a branch pipe, and the plurality of branch pipes are connected to a main pipe, and the air source is connected to the main pipe;

[0033] The air holes are evenly arranged in a matrix on the air box outside the air cavity. The air holes are opened obliquely, with the higher ends of the air holes being located inside and connected to the air cavity, and the lower ends of the air holes being located outside.

[0034] The beneficial effects of the present invention are:

[0035] Multiple filtering mechanisms continuously slide along the circulating slide rails. The filtering mechanisms transport the impurities filtered from the mother liquor away from the filtered mother liquor and send the impurities to a container specially used to hold the impurities. The impurities are separated from the filter screen of the filtering mechanism by automatic shaking and air flow flushing, so that the filter screen always maintains good permeability.

[0036] The filter screen of the filtering mechanism automatically sends out and cleans the impurities just filtered. There is no need to manually clean the impurities on the filter screen of the filtering mechanism, which will not affect the filtering operation. The filtering operation remains continuous, the efficiency of the filtering operation is improved, and the impurities are collected in a centralized manner, which is convenient for impurity processing;

[0037] The operation of the axial flow blades in the upper tank body can prevent the impurities in the mother liquor from being deposited in large quantities at the bottom of the upper tank body, so that the impurities flow up with the mother liquor and flow out from the overflow port to participate in the filtration. The fine filter screen arranged in the first lower tank body can intercept the impurities that may still exist in the mother liquor after filtration, and the fine filter screen cooperates with the turbidity sensor to realize the monitoring of suspended impurities and particulate matter in the mother liquor after filtration, so that when the filtering mechanism is abnormal, it can be discovered in time for manual intervention and maintenance;

[0038] By utilizing the thrust on the filtering mechanism during the filtering process of the mother liquid falling, the sliding of multiple filtering mechanisms in the circulating slide rail can be performed without the need for an external power source or with less external power source, thereby reducing the energy consumption of the filtering mechanism operation and reducing the operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 It is a structural diagram of the present invention;

[0041] Figure 2It is the internal structure diagram of the upper tank body and the first lower tank body;

[0042] Figure 3 It is a structural diagram of the circulating slide rail on the side wall of the base close to the upper pool body;

[0043] Figure 4 A structural diagram of the circulating slide rail on the side wall of the base away from the upper pool body;

[0044] Figure 5 It is a structural diagram of the inner slide rail on the side wall of the base close to the upper pool body;

[0045] Figure 6 A structural diagram of the inner slide rail on the side wall of the base away from the upper pool body;

[0046] Figure 7 It is the structural diagram of the filtering mechanism;

[0047] Figure 8 This is the internal structure diagram of the filter baffle;

[0048] Fig. 9 This is the internal structure diagram of the unloading baffle.

[0049] Figure numerals: 1, upper tank body; 2, first lower tank body; 3, second lower tank body; 4, base; 5, filter baffle; 6, discharge baffle; 7, filter mechanism; 71, slide seat; 72, support rod; 73, slide ball; 74, filter frame; 75, filter screen; 76, connecting block; 77, limit boss; 8, circulation slide rail; 81, filter section; 82, first horizontal section; 83, lower rotary section; 84, discharge section; 85, second horizontal section; 86, upper rotary section; 801, outer slide rail; 802, inner slide rail; 9, air box; 10, axial flow blade; 11, overflow port; 12, fine filter screen; 13, turbidity sensor; 14, block; 15, guide plate; 16, wheel groove; 17, guide wheel; 18, block. DETAILED DESCRIPTION

[0050] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0051] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, 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 to the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0053] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0054] like Figures 1 to 9 As shown, the present invention discloses a system for deep treatment of mother liquor in the production process of aluminum oxide, comprising an upper tank body 1, a filtering device is provided on the side of the upper tank body 1, and a first lower tank body 2 and a second lower tank body 3 are provided on both sides of the lower part of the filtering device. The mother liquor in the upper tank body 1 enters the filtering device by overflow, and the mother liquor is filtered in the process of flowing down in the filtering device. The filtered mother liquor enters the first lower tank body 2, and the filtered impurities enter the second lower tank body 3.

[0055] The filtering device includes a vertically arranged base 4, which is in the shape of a plate and has arc surfaces on the top and bottom. A circulating slide rail 8 is provided on the base 4, and the circulating slide rail 8 is arranged on two side walls of the base 4 close to and away from the upper pool body 1. The circulating slide rails 8 on the two side walls are surrounded at the top and bottom of the base 4.

[0056] The circulating slide rail 8 includes a filtering section 81 , a first horizontal section 82 , a lower rotating section 83 , a discharging section 84 , a second horizontal section 85 , and an upper rotating section 86 which are connected in sequence, and the upper rotating section 86 is connected to the filtering section 81 .

[0057] The filter section 81 is vertically arranged on the side wall of the base 4 close to the upper pool body 1. The filter section 81 is arranged vertically, and the bottom end of the filter section 81 is lower than the bottom of the upper pool body 1. The first horizontal section 82 connected to the bottom end of the filter section 81 is horizontally arranged and extends in the direction away from the upper pool body 1. The end of the first horizontal section 82 away from the upper pool body 1 is connected to the lower rotating section 83, and the lower rotating section 83 extends along the bottom arc surface of the base 4 to the side wall of the base 4 away from the upper pool body 1. The discharge section 84 connected to the end of the lower rotating section 83 is arranged vertically upward on the side wall of the base 4, and the second horizontal section 85 connected to the top end of the discharge section 84 is horizontally arranged and extends in the direction close to the upper pool body 1. The end of the second horizontal section 85 away from the discharge section 84 is at the back of the filter section 81, and the upper rotating section 86 is arranged on the top arc surface of the base 4 and its two ends are respectively connected to the filter section 81 and the second horizontal section 85. The first lower tank body 2 is located below the filtration section 81, and the second lower tank body 3 is located below the discharge section 84. Since there is a horizontal distance between the filtration section 81 and the discharge section 84 that is equivalent to the length of the first horizontal section 82, the first lower tank body 2 and the second lower tank body 3 are staggered in the horizontal direction.

[0058] A plurality of filtering mechanisms 7 arranged at equal intervals are slidably disposed in the circulating slide rail 8, and the plurality of filtering mechanisms 7 circulate and slide in the circulating slide rail 8. The filtering mechanisms 7 slide down in the filtering section 81 and slide up in the unloading section 84.

[0059] The filter mechanism 7 includes a slide seat 71, which is in sliding contact with the outer surface of the base 4. The inner side of the slide seat 71 is provided with an inclined support rod 72, and the end of the support rod 72 away from the slide seat 71 is provided with a sliding ball 73, and the outer diameter of the sliding ball 73 is larger than the support rod 72. From the outside to the inside, the circulating slide rail 8 includes an outer slide rail 801 whose shape is adapted to the support rod 72 and an inner slide rail 802 whose shape is adapted to the sliding ball 73. The support rod 72 slides in the outer slide rail 801, and the sliding ball 73 slides in the inner slide rail 802. Two adjacent sliding balls 73 are connected with a pull rope, and the pull rope is used to make multiple filter mechanisms 7 form a chain. Since the support rod 72 is inclined and the slide seat 71 is in sliding contact with the surface of the base 4, the support rod 72 and the sliding ball 73 cannot rotate and can only slide along the track of the circulating slide rail 8. A plurality of elastic sealing strips are slidingly provided in the outer slide rail 801. The elastic sealing strips are provided between the support rods 72 of two adjacent filtering mechanisms 7. Both ends of the elastic sealing strips are in a concave arc shape adapted to the shape of the support rods 72. The elastic sealing strips slide in the outer slide rail 801 along with the sliding of the filtering mechanism 7. The elastic sealing strips prevent the mother liquid from entering the interior of the circulating slide rail 8.

[0060] The slide 71 is provided with a filter assembly, which includes a rectangular filter frame 74, and a filter screen 75 is arranged in the filter frame 74. Two connecting blocks 76 are arranged at the end of the filter frame 74 close to the slide 71, and the outer edge of the filter frame 74 between the two connecting blocks 76 is in the shape of a concave arc surface. The two connecting blocks 76 are hinged to the two ends of the slide 71, and the axis of rotation of the connecting block 76 is coaxial with the concave arc surface of the outer edge of the filter frame 74. A torsion spring is arranged between the slide 71 and the connecting block 76, so that the filter assembly rotates elastically on the slide 71, and the side wall of the slide 71 close to the filter frame 74 is in the shape of an arc surface that matches the shape of the outer edge of the filter frame 74, and the slide 71 and the outer edge of the filter frame 74 maintain sliding contact. The bottom of the slide 71 is provided with a limiting boss 77 that cooperates with the filter frame 74. The limiting boss 77 is inclined in the filter section 81, and the end of the limiting boss 77 away from the base 4 is the higher end. The elastic force of the torsion spring causes the filter frame 74 to swing toward the boss, so that the filter frame 74 maintains close contact with the boss. When the filter assembly is in the filter section 81 of the circulation track, the filter frame 74 is inclined and the boss is at the bottom of the filter frame 74, and the end of the filter frame 74 close to the upper pool body 1 is the higher end.

[0061] Several adjacent filter mechanisms 7 in the circulating slide rail 8 are the same filter unit, and at least three filter units can be accommodated in the filter section 81. In the sliding direction of the multiple filter mechanisms 7 in the same filter unit in the circulating track, the mesh size of the filter screen 75 is gradually reduced.

[0062] An overflow port 11 is provided at the top of the upper pool body 1 on the side of the filter section 81 of the circulating slide rail 8. The position of the overflow port 11 is higher than the top of the filter section 81. Vertically arranged filter baffles 5 are provided on the bases 4 on both sides of the filter section 81. The filter baffles 5 are connected to the side walls of the lower part of the overflow port 11 of the upper pool body 1, so that the two filter baffles 5, the upper pool body 1 and the base 4 are enclosed to form a vertically arranged rectangular cylinder. When the filter component slides down in the filter section 81, it slides in the cylinder, and the overflowing mother liquor flows downward in the cylinder through multiple filter components.

[0063] The distance between the two filter baffles 5 is adapted to the width of the filter frame 74, that is, the two ends of the filter frame 74 are in sliding contact with the inner walls of the two filter baffles 5 respectively, and the distance between the outer wall of the upper pool body 1 and the inner wall of the base 4 where the filter section 81 is located is smaller than the distance between the end of the filter frame 74 and the base 4, so that when the filter mechanism 7 enters the filter section 81 for filtering, the end of the filter frame 74 is against the outer wall of the upper pool body 1 and the two maintain sliding contact, thereby preventing the mother liquor from flowing through the gap between the filter mechanism 7 and the filter baffle 5 and the upper pool body 1, resulting in the mother liquor not being filtered.

[0064] A wheel groove 16 is provided in the base 4 on the inner side of the connection point between the filtering section 81 and the first horizontal section 82 of the circulating slide rail 8 and the connection point between the unloading section 84 and the second horizontal section 85. A guide wheel 17 is rotatably provided in the wheel groove 16. The guide wheel 17 is adapted to the position of the inner slide rail 802 of the circulating slide rail 8. A groove is provided on the inner wall of the inner slide rail 802 on the side of the guide wheel 17, and the wheel groove 16 is connected with the inner slide rail 802 through the groove. A plurality of quadrangular pyramid-shaped blocks 18 are evenly arranged on the guide wheel 17, and the blocks 18 are adapted to the gap between the sliding balls 73 of two adjacent filtering mechanisms 7. The blocks 18 can slide into the inner slide rail 802 through the slot, and the guide wheel 17 and the sliding balls 73 operate synchronously. The guide wheel 17 rotates and the plurality of filtering mechanisms 7 slide in a circular manner. The blocks 18 of the guide wheel 17 continuously engage in the sliding balls 73 of the adjacent filtering mechanisms 7, so that the relationship between the guide wheel 17 and the plurality of sliding balls 73 is similar to that of a gear and a chain. A motor that can drive the guide wheel 17 to rotate is arranged in the inner base 4 of the guide wheel 17.

[0065] Two unloading baffles 6 parallel to each other are vertically arranged on the side walls of the base 4 on both sides of the unloading section 84. A guide plate 15 is also connected between the ends of the two unloading baffles 6 away from the base 4. The guide plate 15, the two unloading baffles 6 and the base 4 form a cylindrical channel. The width of the unloading baffle 6 is longer than the distance between the lower end of the filter frame 74 of the filter mechanism 7 in the unloading section 84 and the base 4, so that there is a distance between the guide plate 15 and the lower end of the filter frame 74. A plurality of stoppers 14 arranged vertically and equidistantly are arranged on the inner walls of the two unloading baffles 6. The stoppers 14 are in the shape of spherical crowns and are located on the sliding track of the lower end of the filter frame 74 of the filter mechanism 7 in the unloading section 84. When the filter mechanism 7 slides upward in the unloading section 84, the lower end of the filter frame 74 hits the stopper 14 on the inner wall of the unloading baffle 6 and then elastically rotates downward. After sliding away from the stopper 14, the filter frame 74 swings upward under the elastic force of the torsion spring to achieve elastic reset. During the rising process, the lower end of the filter frame 74 continuously contacts the stopper 14 to achieve continuous elastic swing of the filter frame 74 to shake off the impurities filtered out on the filter screen 75.

[0066] The base 4 on both sides of the discharge section 84 is provided with a box groove, which is located inside the two discharge baffles 6. An air box 9 is provided in the box groove. The thickness of the air box 9 is adapted to the box groove, so that the outer surface of the air box 9 is flush with the surface of the base 4. The inside of the air box 9 is a cavity structure. A plurality of partitions are provided inside the air box 9. The plurality of partitions divide the inside of the air box 9 into a plurality of independent air cavities. Each air cavity is connected to a branch pipe. The plurality of branch pipes are gathered and connected to the main pipe. The main pipe is connected to the gas source, and the gas source delivers gas with a certain pressure to the main pipe. A plurality of air holes arranged in a matrix are provided on the outer surface of the air box 9 outside each air cavity. The air holes are opened obliquely. The higher end of the air hole is on the inner side and connected to the air cavity, and the lower end of the air hole is on the outer side. The inclination of the air hole makes the air flow spray obliquely downward. The sprayed air flow flushes the filter screen 75 to wash away impurities.

[0067] The bottom of the side wall of the upper tank body 1 is connected with a liquid inlet pipe, which transports the mother liquid to the bottom of the upper tank body 1. The bottom of the upper tank body 1 is provided with an axial flow blade 10 and a motor driving the axial flow blade 10. The rotation of the axial flow blade 10 causes the mother liquid in the upper tank body 1 to have upward fluidity, and the impurities in the mother liquid float up and finally flow out with the mother liquid at the overflow port 11. A horizontally arranged fine filter 12 is provided in the first lower tank body 2. The fine filter 12 is located at the upper part of the first lower tank body 2. A turbidity sensor 13 is provided on the inner wall of the first lower tank body 2 on the side of the top surface of the fine filter 12, and a liquid outlet pipe is provided on the bottom side wall of the first lower tank body 2.

[0068] The mother liquor enters the bottom of the upper tank body 1, and the axial flow blades 10 in the upper tank body 1 rotate, so that the mother liquor in the upper tank body 1 has an upward fluidity, and the mother liquor flows into the channel between the two filter baffles 5 from the overflow port 11 at the top of the upper tank body 1. In the channel, the mother liquor passes through the filter screens 75 of the filter mechanism 7 in the multiple filter sections 81 from top to bottom in sequence, and the multiple filter screens 75 filter the mother liquor, and the mesh size of the filter screens 75 of the multiple filter mechanisms 7 in the filter unit gradually decreases to achieve graded filtration of the mother liquor. The mother liquor flows downward and finally enters the first lower tank body 2. The fine filter screen 12 in the first lower tank body 2 serves as the last barrier to intercept impurities in the mother liquor to prevent the impurities that may still exist in the mother liquor from escaping, and also serves as a detection structure. When the turbidity sensor 13 on the side of the fine filter screen 12 detects that the concentration of impurities and particulate matter in the mother liquor is high, the filtration device is abnormal and needs to be manually repaired.

[0069] The power for the sliding of the multiple filtering mechanisms 7 in the circulating slide rail 8 can come from the thrust during the flow of the mother liquid, which generates thrust on the multiple filtering mechanisms 7 during the downward flow of the mother liquid in the filtering section 81, or can come from the guide wheel 17 driven by the motor to rotate. When the flow rate of the mother liquid output from the overflow port 11 is large enough to push the filtering mechanism 7 to slide, the motor may not intervene to drive the guide wheel 17. When the flow rate of the mother liquid output from the overflow port 11 is small and insufficient to push the filtering mechanism 7 to slide or slide very slowly, the motor may intervene to drive the guide wheel 17 to rotate to drive the sliding ball 73 in the inner slide rail 802 to slide, thereby driving the multiple filtering mechanisms 7 to slide.

[0070] The impurities filtered out by the filter mechanism 7 in the filter section 81 move with the filter mechanism 7. When the filter mechanism 7 slides down to the bottom of the filter section 81, it enters the first horizontal section 82. The filter mechanism 7 slides horizontally in the first horizontal section 82 and gradually slides away from the first lower pool body 2 and enters the top of the second lower pool body 3. The filter mechanism 7 slides in the lower rotating section 83 at the end of the first horizontal section 82 away from the filter section 81. After sliding through the bottom of the base 4, the filter mechanism 7 turns 180 degrees and enters the discharge section 84 and rises in the discharge section 84. At this time, the filtered impurities are in the filter section 83. At the bottom of the net 75, impurities fall out under the action of gravity. During the rising process of the filter mechanism 7 in the unloading section 84, the lower end of the filter frame 74 continuously passes through multiple blocks 14, so that the filter frame 74 continuously swings elastically back and forth to shake off the impurities at the bottom of the filter screen 75. During the rising process of the filter mechanism 7, the air holes on the outer surface of the air box 9 continuously output air flow to flush the filter screen 75, further flushing the impurities on the filter screen 75. The impurities fall from the gap between the inner side of the guide plate 15 and the filter mechanism 7 into the second lower pool body 3, and the second lower pool body 3 collects the impurities for recycling.

[0071] The filter mechanism 7 slides up to the top in the unloading section 84 and then slides into the second horizontal section 85. In the second horizontal section 85, it slides laterally toward the filter section 81 and enters the upper rotating section 86. After the filter mechanism 7 slides through the upper rotating section 86 and slides over the top of the base 4 and turns 180 degrees, the filter mechanism 7 enters the filter section 81 to filter the mother liquor again.

[0072] The multiple filtering mechanisms 7 of the present invention continuously slide along the circulating slide rail 8. The filtering mechanism 7 transports the impurities filtered out of the mother liquor away from the filtered mother liquor, and transports the impurities to a container specially used to contain the impurities. The impurities are separated from the filter screen 75 of the filtering mechanism 7 by automatic shaking and air flow flushing, so that the filter screen 75 always maintains good permeability.

[0073] The filter screen 75 of the filtering mechanism 7 automatically sends out and cleans the impurities just filtered. There is no need to manually clean the impurities from the filter screen 75 of the filtering mechanism 7, which will not affect the filtering operation. The filtering operation remains continuous, the efficiency of the filtering operation is improved, and the impurities are collected in a centralized manner, which is convenient for processing the impurities.

[0074] The operation of the axial flow blades 10 in the upper tank body 1 can prevent impurities in the mother liquor from being deposited in large quantities at the bottom of the upper tank body 1, so that the impurities flow up with the mother liquor and flow out from the overflow port 11 to participate in the filtration. The fine filter screen 12 arranged in the first lower tank body 2 can intercept impurities that may still exist in the mother liquor after filtration, and the fine filter screen 12 cooperates with the turbidity sensor 13 to realize the monitoring of suspended impurities and particulate matter in the mother liquor after filtration, so that when the filtering mechanism 7 is abnormal, it can be discovered in time to facilitate manual intervention for maintenance.

[0075] By utilizing the thrust on the filtering mechanism 7 during filtering of the mother liquid during its falling process, the sliding of multiple filtering mechanisms 7 in the circulating slide rail 8 does not require an external power source or requires less external power source, thereby reducing the energy consumption of the filtering mechanism 7 and reducing operating costs.

[0076] The above embodiments are only preferred embodiments of the present invention and are not limitations of the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A system for deep treatment of mother liquor in the process of alumina production, characterized in that: include: Upper pool body; Axial flow blades are rotatably arranged at the bottom of the upper tank body; The filtering device is arranged on the side of the upper pool body and comprises: Pedestal; A circulating slide rail is arranged on the base; Multiple filtering mechanisms are slidably arranged in a circulating slide rail; The first lower tank body and the second lower tank body are arranged at the lower part of the filtering device; A fine filter is provided in the first lower tank body; A turbidity sensor is arranged on the inner wall of the first lower tank body at the side of the top surface of the fine filter; The circulating rails on the upper parts of the first lower tank body and the second lower tank body are arranged vertically, and there is a gap between the circulating rails above the first lower tank body and the second lower tank body in the horizontal direction. The two ends of the circulating rails above the first lower tank body and the second lower tank body are respectively enclosed at the top and bottom of the base, and the filtering mechanism slides unidirectionally in the circulating rails; An air box connected to an air source is provided on the side of the circulation slide rail above the second lower pool body, and a plurality of air holes are provided on the air box; The filtering mechanism comprises a sliding seat slidably connected to the circulating slide rail, a filtering assembly is arranged on the sliding seat, and the filtering assembly comprises a filter frame connected to the sliding seat, and a filter screen is arranged in the filter frame.

2. The system for deep treatment of mother liquor in the alumina production process according to claim 1, characterized in that: The circulating slide rail comprises a filtering section, a first horizontal section, a lower rotating section, a discharging section, a second horizontal section, and an upper rotating section which are connected in sequence, and the upper rotating section is connected to the filtering section; The filter section is vertically arranged on the side wall of the base close to the upper pool body, the first horizontal section connected to the bottom end of the filter section is horizontally arranged and extends in the direction away from the upper pool body, the end of the first horizontal section away from the upper pool body is connected to the lower rotating section, the lower rotating section extends along the bottom of the base to the side wall of the base away from the upper pool body, the discharge section connected to the end of the lower rotating section is vertically arranged upward on the side wall of the base, the second horizontal section connected to the top end of the discharge section is horizontally arranged and extends in the direction close to the upper pool body, the end of the second horizontal section away from the discharge section is at the back of the filter section, the upper rotating section is arranged at the top of the base and its two ends are respectively connected to the filter section and the second horizontal section, the first lower pool body is below the filter section, and the second lower pool body is below the discharge section.

3. The system for deep treatment of mother liquor in the alumina production process according to claim 2, characterized in that: Several adjacent filter mechanisms in the circulating slide rail are the same filter unit, and the filter section can accommodate at least three filter units. In the sliding direction of the multiple filter mechanisms in the same filter unit, the mesh size of the filter screen gradually decreases.

4. The system for deep treatment of mother liquor in the alumina production process according to claim 2, characterized in that: An overflow port is provided at the top of the upper pool body on the side of the filter section, and the position of the overflow port is higher than the top of the filter section. Vertically arranged filter baffles are provided on the bases on both sides of the filter section, and the filter baffles are connected to the side walls of the lower part of the overflow port of the upper pool body. The two ends of the filter frame are in sliding contact with the inner walls of the two filter baffles in the filter section, and the end of the filter frame away from the slide seat is in sliding contact with the side wall of the upper pool body in the filter section.

5. The system for deep treatment of mother liquor in the alumina production process according to claim 4, characterized in that: The filter frame is provided with two connecting blocks at the end close to the slide seat, the two connecting blocks are hinged to the two ends of the slide seat, and the slide seat is provided with a limiting boss that cooperates with the filter frame; The limiting boss is inclined in the filtering section and is located at the bottom of the filter frame, and the end of the limiting boss away from the base is the higher end.

6. The system for deep treatment of mother liquor in the alumina production process according to claim 5, characterized in that: The outer edge of the filter frame between the two connecting blocks is in the shape of a concave arc surface, the axis of rotation of the connecting block is coaxial with the concave arc surface of the outer edge of the filter frame, the side wall of the sliding seat close to the filter frame is in the shape of an arc surface adapted to the shape of the outer edge of the filter frame, and a torsion spring is provided between the sliding seat and the connecting block.

7. The system for deep treatment of mother liquor in the alumina production process according to claim 2, characterized in that: An inclined support rod is provided inside the slide seat, and a sliding ball is provided at the end of the support rod away from the slide seat, and the outer diameter of the sliding ball is larger than the support rod; The circulating slide rail comprises, from outside to inside, an outer slide rail whose shape matches the support rod and an inner slide rail whose shape matches the slide ball. The support rod slides in the outer slide rail, and the slide ball slides in the inner slide rail. Two adjacent slide balls are connected with a pull rope.

8. The system for deep treatment of mother liquor in the alumina production process according to claim 7, characterized in that: A wheel groove is provided in the base inside the connection between the filtering section and the first horizontal section and the connection between the discharge section and the second horizontal section. A guide wheel is rotatably provided in the wheel groove. The guide wheel is adapted to the position of the inner slide rail of the circulating slide rail. A groove is provided on the inner wall of the inner slide rail at the side of the guide wheel. The wheel groove is connected to the inner slide rail through the groove. The guide wheel is evenly provided with a plurality of quadrangular pyramid-shaped blocks, which are adapted to the gap between two adjacent filter mechanism sliding balls. The blocks can slide into the inner slide rail through the slots. The guide wheel and the sliding balls operate synchronously, and a motor for driving the guide wheel to rotate is provided in the inner base of the guide wheel.

9. The system for deep treatment of mother liquor in the alumina production process according to claim 6, characterized in that: Two unloading baffles parallel to each other are vertically arranged on the side walls of the base on both sides of the unloading section, and a guide plate is also connected between the ends of the two unloading baffles away from the base. A plurality of spherical crown-shaped baffles arranged vertically and at equal intervals are provided on the inner walls of the two unloading baffles, and the baffles are located on the sliding track at the lower end of the filter frame of the filter mechanism in the unloading section.

10. The system for deep treatment of mother liquor in the alumina production process according to claim 9, characterized in that: The bases on both sides of the discharge section are provided with box grooves, the box grooves are located inside the two discharge baffles, the air box is arranged in the box grooves, the thickness of the air box is adapted to the box grooves, and the outer surface of the air box is flush with the surface of the base; The interior of the air box is a cavity structure, and a plurality of partitions are arranged inside the air box. The plurality of partitions divide the air box into a plurality of independent air cavities, each of the air cavities is connected to a branch pipe, and the plurality of branch pipes are connected to a main pipe, and the air source is connected to the main pipe; The air holes are evenly arranged in a matrix on the air box outside the air cavity. The air holes are opened obliquely, with the higher ends of the air holes being located inside and connected to the air cavity, and the lower ends of the air holes being located outside.

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