Air floating equipment of TMAH wastewater treatment system

Abstract

The utility model relates to air flotation equipment of a TMAH wastewater treatment system. The air flotation equipment comprises a pretreatment tank I, a neutralization reaction tank II and an air flotation tank III which are connected in sequence, a plurality of aeration holes are uniformly formed in a bottom plate of the air floatation tank III and are connected with an aeration pipe at the bottom of the air floatation tank III; the air floatation tank III is in a circular tank shape, and the drainage mechanism is arranged in the air floatation tank III and can revolve around the axis of the air floatation tank III; when the drainage mechanism rotates, water in the air floatation tank III can flow in the same direction, namely a pushing flow direction; the drainage mechanism is communicated with the neutralization reaction tank II; when being drained from the drainage mechanism, water can revolve and flow around the axis of the air floatation tank III, namely the drainage flow direction; the pushing flow direction is opposite to the drainage flow direction, so that the water in the air floatation tank III is kept relatively static. The device disclosed by the utility model has the beneficial effects that the flocculate can be continuously removed, and the flocculate can quickly float upwards, so that the flocculate removal effect is good.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing wastewater treatment technology, and in particular to an air flotation device for a TMAH wastewater treatment system. Background Technology

[0002] TMAH stands for tetramethylammonium hydroxide, which is widely used in the semiconductor and electronics industries (as a photoresist developer). Because TMAH wastewater is highly toxic and alkaline, it requires treatment before discharge.

[0003] For TMAH wastewater generated during semiconductor manufacturing, the main stages include pretreatment, neutralization reaction, precipitation separation, filtration purification, and post-treatment. In the neutralization reaction stage, aluminum sulfate is added to the wastewater as a coagulant and thoroughly stirred, allowing aluminum ions to combine with the colloidal substances produced by TMAH decomposition to form flocculent precipitates. In the precipitation separation stage, a sedimentation tank is typically used, allowing the flocculent precipitates to fall to the bottom. A sludge scraper is then used to scrape away the flocculent material at intervals.

[0004] Because sedimentation tanks operate statically, the process takes a considerable amount of time, which is not conducive to sustainable and efficient wastewater treatment. Currently, some new methods are being used—namely, air flotation equipment—which uses rising air bubbles to lift and remove flocs. However, when water circulates within the air flotation equipment, the water flow disturbs the flocs, hindering their proper buoyancy and resulting in less than ideal floc removal efficiency.

[0005] Based on this, our company has carried out corresponding optimization design for TMAH processing, requiring it to have both high processing efficiency and good processing effect. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an air flotation device for the TMAH wastewater treatment system, which solves the problems of the inability to continuously remove flocs from wastewater or the poor floc removal effect when continuously removing flocs from wastewater.

[0007] The purpose of this utility model is achieved through the following technical solution: a flotation device for a TMAH wastewater treatment system, comprising a pretreatment tank I, a neutralization reaction tank II, and a flotation tank III connected in sequence;

[0008] The bottom plate of the flotation tank III has multiple aeration holes evenly distributed, and the aeration holes are connected to the aeration pipes at the bottom of the flotation tank III.

[0009] The flotation tank III is circular, and the drainage mechanism is located inside the flotation tank III. The drainage mechanism can revolve around the axis of the flotation tank III. When the drainage mechanism rotates, it can make the water in the flotation tank III flow in the same direction - which is called the driving flow direction.

[0010] The drainage mechanism is connected to the neutralization reaction tank II. When water is discharged from the drainage mechanism, it can revolve around the axis of the flotation tank III – this is called the drainage flow direction.

[0011] The direction of the push flow is opposite to that of the drainage flow, so that the water in the flotation tank III remains relatively still.

[0012] As a preferred technical solution of this application, the lower part of the drainage mechanism extends into the flotation tank III, and the water discharged by the drainage mechanism is discharged from the lower part of the liquid in the flotation tank III.

[0013] As a preferred technical solution of this application, the flotation tank III is further equipped with a flocculation collection mechanism, which is located at the liquid surface of the flotation tank III. The flocculation collection mechanism is in the shape of a roller, and its radial cross-section is a spiral structure. When the flocculation collection mechanism rotates, it can collect the flocs on the liquid surface in the flotation tank III through the spiral structure. When the flocculation collection mechanism rotates, it can drive the liquid on the liquid surface in the flotation tank III to revolve around the axis of the flotation tank III. The direction of rotation of the liquid on the liquid surface is called the impurity removal flow direction. The impurity removal flow direction is the same as the drainage flow direction, and the two act together to cancel out the pushing flow direction.

[0014] Furthermore, the flocculation collection mechanism also revolves around the axis of the flotation tank III, and the direction and speed of the flocculation collection mechanism are the same as those of the drainage mechanism revolving around the axis of the flotation tank III.

[0015] Furthermore, the flotation tank III is a circular steel tank body, with a central cylinder A welded to its center, forming an annular cavity. A rotatable long base frame is fitted onto the central cylinder A, with its middle portion resting on the central cylinder A and its two ends resting on the edges of the steel tank body via rollers. These rollers are connected to a first drive mechanism; when the first drive mechanism operates, the rollers roll, allowing the long base frame to rotate around the axis of the flotation tank III. A drainage mechanism is fixed to the right side of the long base frame, and a flocculation collection mechanism is installed on the left side.

[0016] As a preferred technical solution of this application, the drainage mechanism includes an upper water tank and a lower water tank, which are fixed to the upper and lower surfaces of the right side of the long base frame, respectively. The lower water tank is divided into multiple chambers by multiple arc-shaped partitions, each chamber connected to the upper water tank via a corresponding pipe. Multiple water holes are opened at the lower part of the front / rear wall of the lower water tank. Water flows from the upper water tank into different chambers of the lower water tank and then exits through the water holes. The flow direction of the water exiting from the water holes is tangent to the arc shape of the partition, forming a structure that cancels out the drainage flow direction from the pushing flow direction.

[0017] As a preferred technical solution of this application, the flocculation collection mechanism includes a spiral cylinder and end cylinders. The spiral cylinder is made of steel plate rolled into a cylindrical shape, and its radial cross-section is spiral after rolling. Both ends of the spiral cylinder are closed by end caps, and end cylinders are welded to the end caps, with the end cylinders communicating with the central cavity at the axis of the spiral cylinder. When the spiral cylinder rotates, it can collect the flocculated material at the liquid surface through the open end of the spiral cylinder, and as the spiral cylinder rotates, the flocculated material can slide along the spiral wall and gradually accumulate in the central cavity of the spiral cylinder.

[0018] Furthermore, the long base frame has a large through-hole, and the spiral cylinder is positioned at this through-hole, allowing its opening to scoop up the liquid surface when it rotates. A grooved wheel is fitted onto one end of the spiral cylinder, and the grooved wheel is engaged with the upper edge of the central cylinder A. The other end of the spiral cylinder is mounted on the long base frame via a support base, and this end is also connected to a second drive mechanism; when the second drive mechanism operates, it allows the flocculation collection mechanism to rotate. Screw shafts are installed in the central cavity of the spiral cylinder and in the end cylinders at the left and right positions, and these screw shafts are connected to a third drive mechanism; when the third drive mechanism operates, it allows the flocculated material at the center of the spiral cylinder to be discharged from the end cylinders.

[0019] As a preferred technical solution of this application, the flotation tank III is supported by a support frame, and a central cylinder B is provided inside the central cylinder A of the flotation tank III, with an annular gap between the central cylinder A and the central cylinder B. The lower end of the central cylinder B is connected to the neutralization reaction tank via a pipe and a pump; the upper end of the central cylinder B is connected to the upper water tank via a universal joint, forming a system where water can enter the upper water tank without affecting the upper water tank's revolution around the axis of the flotation tank III.

[0020] Furthermore, the annular gap between the central cylinder A and the central cylinder B constitutes a flocculation chamber, which is connected via a corresponding flocculation discharge pipe; a drainage pipe is provided on the upper part of the outer wall of the flotation tank III. The bottom of the flotation tank III has a sludge collection trough, which is connected to a sludge discharge pipe; a sludge discharge plate is detachably installed on the front / rear wall panel of the lower water tank, which can sweep the sludge at the bottom of the flotation tank III into the sludge collection trough when the lower water tank rotates.

[0021] To facilitate understanding, the working process of this solution will be explained as follows:

[0022] Working process: (1) The third motor works, causing the long base frame to rotate counterclockwise. When the long base frame rotates counterclockwise, the rear wall of the lower water tank (drainage mechanism) pushes the water in the flotation tank III (round steel tank body) counterclockwise; (2) The water flowing out from the neutralization reaction tank II enters the drainage mechanism and then is discharged from the water hole at the bottom of the front wall of the lower water tank. The water discharged from the water hole is discharged clockwise; (3) The flocculation collection mechanism rotates with the long base frame. When the second motor works, it can make the flocculation collection mechanism rotate. When the flocculation collection mechanism rotates, the opening of the spiral cylinder will collect the flocculated material at the liquid surface. (and a small amount of water) scoop up, and as the rotation continues, the scooped-up flocs (and a small amount of water) slide from the open-spiral channel into the central cavity. When the third motor works, it discharges the flocs (and a small amount of water) in the central cavity from the end shaft; (4) In addition, when the floc collection mechanism rotates, it can make the liquid at the liquid surface flow clockwise when scooping up the corresponding flocs; (5) The water discharged clockwise from the water hole and the water flowing clockwise when scooping up the flocs cancel each other out in the circumferential direction with the water flowing counterclockwise from the rear wall of the lower water tank, so that the water remains relatively still.

[0023] Working principle: (1) The long base frame rotates counterclockwise around the central cylinder A at the center of the round steel tank. The drainage mechanism on the right side of the long base frame drains water, and the drained water rotates clockwise at the bottom of the round steel tank. The flocculation collection mechanism on the left side of the long base frame can rotate itself. When it rotates, it can collect the flocculents on the liquid surface and make the upper liquid surface of the round steel tank rotate clockwise. That is, the flow direction of the water discharged by the drainage mechanism and the flow direction of the water on the liquid surface caused by the flocculation collection mechanism cancel each other out with the flow direction of the water pushed by the drainage mechanism in the round steel tank, so that the water in the round steel tank remains relatively still in the circumferential direction. (2) When the bubbles in the aeration holes rise from the round steel tank, the bubbles push the flocculents in the sewage upward. Since the water in the round steel tank remains relatively still in the circumferential direction, the bubbles can quickly push the flocculents upward, so that the flocculents can quickly float to the liquid surface.

[0024] This utility model has the following advantages:

[0025] It can continuously remove flocs, and the flocs can quickly float to the surface - resulting in good floc removal effect;

[0026] Specifically:

[0027] In existing technologies, TMAH in wastewater, after being decomposed and coagulated to form flocs, is usually left to settle in a sedimentation tank. However, wastewater cannot be continuously fed into the sedimentation tank (as this would affect the settling of the flocs), resulting in low sedimentation efficiency. Currently, some air flotation devices have emerged, which continuously feed wastewater containing flocs into the flotation equipment. Bubbles are generated at the bottom of the equipment, and as the bubbles rise, they push the flocs upwards to the surface (and then remove them from the surface). This method, because the wastewater is continuously fed into the flotation equipment, can continuously remove flocs in actual industrial production, thus improving floc removal efficiency. However, a problem exists: the continuous flow of water into the flotation equipment affects the floc's buoyancy, resulting in less than ideal floc buoyancy and ultimately less than ideal floc removal efficiency.

[0028] In this scheme, an air flotation device is also used. Although the wastewater continuously flows into the air flotation tank III, by controlling the rotation direction and speed of the drainage mechanism, the drainage direction and speed of the drainage mechanism, and the rotation direction and speed of the floc collection mechanism, the water in the air flotation tank III is kept relatively still in the circumferential direction (flowing only from bottom to top). This allows the flocs to float quickly, improving the floc removal effect (the flocs will not rotate uniformly at the bottom and middle of the air flotation tank III), and can also continuously treat the wastewater to remove flocs. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of this utility model;

[0030] Figure 2 A schematic diagram of the drainage and flocculation collection mechanisms installed at flotation tank III (aeration pipes are not shown).

[0031] Figure 3 for Figure 2 Schematic diagram of the structure of BB;

[0032] Figure 4 for Figure 2 Schematic diagram of the structure of AA;

[0033] Figure 5 This is a schematic diagram of the flocculation collection mechanism;

[0034] Figure 6 This is a top view of the structure of the dissolved air flotation tank III (aeration holes are not shown).

[0035] Figure 7 This is a structural diagram of the lower water tank;

[0036] Figure 8 This is a top-down structural diagram of the lower water tank;

[0037] Figure 9 This is a schematic diagram of the steel tank structure;

[0038] In the diagram: 10-drainage mechanism, 11-upper water tank, 12-lower water tank, 1201-arc-shaped partition, 1202-water hole;

[0039] 20-Flocculation collection mechanism, 21-Screw cylinder, 2101-Auger shaft, 22-End cylinder, 23-Groove wheel;

[0040] 30-Steel pool body, 31-Central cylinder A, 3101-Annular platform A, 32-Long base frame, 3201-Annular platform B, 33-Roller, 34-Central cylinder B, 35-Drainage pipe, 36-Sludge collection tank, 37-First motor, 38-Second motor, 39-Third motor. Detailed Implementation

[0041] The present invention will be further described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0042] It should be noted that the orientation or positional relationship indicated by terms such as "left" and "right" is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of this utility model is usually placed in during use, or the orientation or positional relationship that is commonly understood by those skilled in the art. Such terms are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0043] It should be noted that the existing related technologies described here, for TMAH wastewater generated during semiconductor manufacturing, mainly include several stages: pretreatment, neutralization reaction, precipitation separation, filtration purification, and post-treatment. Pretreatment includes pre-recovery, i.e., recovering some useful substances (such as precious metals like nickel and copper). The neutralization reaction is divided into two steps: the first step involves adding reagents to enhance hydrolysis of the wastewater, generating organic matter; the second step involves adding coagulants to cause suspended solids and colloidal substances in the wastewater to coagulate and precipitate (forming flocculants), removing impurities. Then, in the precipitation separation process, flocculants are removed by precipitation.

[0044] However, conventional sedimentation separation typically involves allowing flocs to settle in a static sedimentation tank. Since settling flocs takes time, the water in the tank cannot maintain a constant flow, thus affecting sedimentation efficiency. Therefore, some air flotation devices have emerged on the market. These devices generate air bubbles that adhere to the flocs, causing them to float to the surface. This allows for floc removal even in flowing water, improving floc removal efficiency.

[0045] However, the problem is that even in air flotation equipment, because the water is constantly flowing, the rise of flocs is still easily affected by the water flow (and thus cannot rise well), thereby affecting the flocculation effect.

[0046] To address the aforementioned issues, this solution offers the following approach: through appropriate structural design, the water in the flotation equipment is kept relatively still, thereby reducing the impact of water flow on the flocs and facilitating their floating.

[0047] The following description uses specific embodiments. It should be noted that, unless otherwise specified, the embodiments, features, and technical solutions in this utility model can be combined with each other.

[0048] like Figures 1-9 As shown, a flotation device for a TMAH wastewater treatment system includes a pretreatment tank I, a neutralization reaction tank II, and a flotation tank III connected in sequence. TMAH wastewater is pretreated in the pretreatment tank I, and then a reagent is added and stirred in the neutralization reaction tank II to produce flocculants (the neutralization reaction tank II consists of two tanks connected in series, one for hydrolysis and the other for flocculation; only the tank for flocculation is shown in the figure).

[0049] Among them, the flotation tank III is a circular tank, and multiple aeration holes are evenly opened on the bottom plate of the flotation tank III. The aeration holes are connected to the aeration pipes at the bottom of the flotation tank III.

[0050] A drainage mechanism 10 is installed in the flotation tank III. The drainage mechanism 10 can revolve around the axis of the flotation tank III as the central axis. When the drainage mechanism 10 revolves, it can also push the flotation tank III to rotate. The direction of the water flow that is pushed is called the pushing direction.

[0051] In addition, the drainage mechanism 10 is also connected to the neutralization reaction tank II. When water is discharged from the neutralization reaction tank II through the drainage mechanism 10, the discharged water also revolves around the axis of the flotation tank III. The direction of the discharged water is called the drainage direction.

[0052] During operation, TMAH wastewater undergoes pretreatment in pretreatment tank I, followed by hydrolysis and flocculation in neutralization reaction tank. The wastewater then enters and exits through drainage mechanism 10. The discharged water revolves around the axis of floating tank III (e.g., clockwise rotation). Furthermore, drainage mechanism 10 revolves around the axis of floating tank III (e.g., counterclockwise rotation). Because the direction of the discharged water's revolution is opposite to that of drainage mechanism 10, adjusting the flow rate of the discharged water and the rotation speed of drainage mechanism 10 allows the water in floating tank III to remain relatively still in the circumferential direction, thus facilitating the normal floating of flocs (preventing turbulence). Small bubbles are generated at the aeration holes. As these bubbles rise, they press against the bottom of the flocs, allowing them to float more effectively (because the water is relatively still in the circumferential direction, the bubbles also rise vertically, thus better lifting the flocs). This results in high floc removal efficiency and good removal effect.

[0053] In this scheme, the lower part of the drainage mechanism 10 extends into the flotation tank III, and the water discharged by the drainage mechanism 10 is discharged from the lower part of the liquid in the flotation tank III.

[0054] In this scheme, a drainage pipe 35 is provided on the upper part of the outer wall of the flotation tank III.

[0055] The following is a further explanation of the air flotation tank III.

[0056] A flocculation collection mechanism 20 is also installed in the flotation tank III. The flocculation collection mechanism 20 is located at the liquid surface of the flotation tank III. The flocculation collection mechanism 20 is in the shape of a roller, and its radial cross section is in the shape of a spiral structure (so that there is an opening at the edge and a central cavity at the center, and the opening is gradually connected to the central cavity through the spiral cavity). When it is set horizontally, its opening is in contact with the liquid surface of the flotation tank III. As the flocculation collection mechanism 20 rotates, the opening can scoop up the flocs (and part of the liquid) at the liquid surface and allow the flocs to gradually slide into the central cavity for collection through the spiral cavity.

[0057] It should be noted that when the flocculation collection mechanism 20 rotates, because the opening contacts the liquid surface (and scoops up the flocs and some liquid), it also pushes the liquid on the inner surface of the flotation tank III. This push causes the liquid at the liquid surface to revolve around the axis of the flotation tank III. The flow direction of the liquid at the liquid surface is called the impurity removal flow direction. Furthermore, the impurity removal flow direction is the same as the drainage flow direction. In specific operation, for example, the drainage flow direction is clockwise at the lower part of the liquid surface, the impurity removal flow direction is clockwise at the upper part of the liquid surface, and the drainage mechanism 10 rotates counterclockwise. This allows the water in the flotation tank III to remain relatively still in the circumferential direction.

[0058] Furthermore, the flocculation collection mechanism 20 also revolves around the axis of the flotation tank III, and the direction of revolution and the speed of rotation of the flocculation collection mechanism 20 are the same as the direction of revolution and the speed of rotation of the drainage mechanism 10 around the axis of the flotation tank III.

[0059] The structure of flotation tank III and the installation of drainage mechanism 10 and flocculation collection mechanism 20 in flotation tank III are described below.

[0060] See Figure 9 The dissolved air flotation tank III is a circular steel tank body 30, which is supported by a support frame. Multiple aeration holes are opened on the bottom plate of the steel tank body 30, and multiple aeration pipes are installed at the bottom of the steel tank body 30. The aeration pipes are connected to the aeration holes (the aeration holes and aeration pipes are not shown in the figure).

[0061] A central cylinder A31 is welded at the center of the steel pool body 30, and the two together form an annular cavity.

[0062] See Figure 4 A long base frame 32 is fitted onto the central cylinder A31. Specifically, the long base frame 32 has a central hole near the center between the left and right sides. Below the central hole, an annular platform B3201 is welded onto the long base frame 32. An annular platform A3101 is fitted onto and fixed to the central cylinder A32. When the long base frame 32 is fitted onto the central cylinder 32, the annular platform B3201 is fitted onto the central cylinder 32, and the annular platform B3201 and the annular platform A3101 are positioned opposite each other. The opposite surfaces between them have grooves, and ball bearings are placed in the grooves. When the long base frame 32 rotates around the central cylinder 31, the annular platform B3201 rotates by being pressed against the annular platform A3101 by the ball bearings.

[0063] In addition, see Figure 2 and Figure 3 The two ends of the long base frame 32 rest on the edges of the steel pool body 30. Specifically, lugs are fixed to the bottom surfaces of both ends of the long base frame 32, and rollers 33 are provided on the lugs. The rollers 33 are driven and connected to the first motor 37 (the drive motor is fixed on the lugs / fixed on the long base frame 32). In addition, a reinforcing ring is welded to the upper edge end face of the steel pool body 30, and the rollers 33 are in contact with the upper surface of the reinforcing ring. When the first motor 37 is working, it can make the long base frame 32 rotate around the axis of the round steel pool body 30.

[0064] See Figure 2 and Figure 4A central cylinder B34 is also installed inside the central cylinder A31 of the round steel tank body 10, and there is an annular gap between the central cylinder A31 and the central cylinder B34. The lower end of the central cylinder B34 is connected to the neutralization reaction tank via a pipe and a pump. The upper end of the central cylinder B34 is connected to the drainage mechanism 10 via a universal joint, so that water can enter the drainage structure 10 without affecting the drainage mechanism 10's revolution around the axis of the flotation tank III.

[0065] See Figure 6 and Figure 9 A drainage mechanism 10 is fixed on the right side of the long base frame 32, and a flocculation collection mechanism 20 is installed on the left side of the long base frame 32.

[0066] The structure of the drainage mechanism 10 will be further explained below.

[0067] See Figure 2 The drainage mechanism 10 includes an upper water tank 11 and a lower water tank 12, which are fixed to the upper and lower surfaces of the right side of the long base frame 32, respectively. (See reference...) Figure 8 Multiple arc-shaped baffles 1201 are installed inside the lower water tank 12 to divide it into multiple chambers, each chamber being connected to the upper water tank 11 via a corresponding pipe; see reference. Figure 7 Multiple water holes 1202 are provided at the lower part of the front wall of the lower water tank 12.

[0068] During operation, water flows from the upper water tank 11 into different chambers of the lower water tank 12 and is then discharged through the water hole 1202. The direction of the water discharged from the water hole 1202 is tangent to the arc of the arc-shaped baffle 1201, forming a structure that cancels out the drainage direction and the driving direction.

[0069] The installation and structure of the flocculation collection mechanism 20 will be further explained below.

[0070] See Figure 2 , Figure 3 , Figure 4 , Figure 5 The structure of the flocculation collection mechanism 20 is described below:

[0071] Includes a spiral cylinder 21 and an end cylinder 22; wherein, see reference Figure 5 The spiral cylinder 21 is made of steel plate rolled into a cylindrical shape. After rolling, its radial cross-section is spiral. The spiral cylinder 21 has an opening at a certain position at the outer radial end after rolling, and a central cavity is formed at the center of the spiral cylinder 21. The opening is connected to the central cavity through the spiral cavity. When the spiral cylinder 21 rotates, the flocculent material located at the liquid surface enters the central cavity through the opening, the spiral cavity, and finally the central cavity.

[0072] The spiral cylinder 21 is closed at both ends by end caps, and an end cylinder 22 is welded onto the end caps. The end cylinder 22 is connected to the central cavity at the axis of the spiral cylinder 21.

[0073] In addition, see Figure 3 and Figure 5 A auger shaft 2101 is provided along the left and right end cylinders 22 and at the position of the central cavity. The auger shaft 2101 is connected to the third motor 39. When the third motor 39 rotates, it can discharge the debris in the central cavity from the end cylinder 22.

[0074] See Figure 2 , Figure 3 , Figure 4 , Figure 6 The installation of the flocculation collection mechanism 20 is explained below:

[0075] The left part of the long base frame 32 has a large frame hole that runs through the top and bottom. The spiral cylinder 21 is placed in the large frame hole (it can extend out of the large frame hole, so that when the spiral cylinder 21 rotates, its opening can scoop up the liquid surface).

[0076] Furthermore, a grooved wheel 23 is fitted on the end cylinder 22 at the right end of the spiral cylinder 21. The grooved wheel 23 is engaged at the upper edge of the central cylinder A31. When the long base frame 32 rotates, the grooved wheel 23 can roll on the upper edge of the central cylinder A31.

[0077] Furthermore, the left end cylinder 22 of the spiral cylinder 21 is installed with a bearing and a support seat, which is fixed on the long base frame 32. A second motor 38 is fixed on the support seat.

[0078] During operation, the second motor 38 rotates, causing the spiral drum 21 to rotate, which allows the open end to scoop up the flocs from the liquid surface. As the rotation continues, the flocs slide down through the spiral channel to the central cavity. When the third motor 39 is working, it drives the auger shaft 2102 to rotate, thereby discharging the flocs in the central cavity to the annular gap cavity between the central drum A31 and the central drum B34 (the annular gap is the flocculation discharge cavity, which is connected by a flocculation discharge pipe), and then discharges them from the annular gap cavity.

[0079] See Figure 6 and Figure 9 At the bottom of the flotation tank III, there is a sludge collection trough 36, which is connected to the sludge discharge pipe. A sludge discharge plate is placed on the rear wall of the lower water tank 12 by magnetic attraction. When the sludge discharge plate is magnetically attached to the rear wall of the lower water tank 12, as the long base frame 32 rotates, the sludge discharge plate can sweep the sludge at the bottom of the flotation tank III into the sludge collection trough 36 (the sludge is some small particulate impurities in the sewage, not flocculent material, and can be cleaned once every once in a while. When cleaning is not required, the sludge discharge plate can be removed directly).

[0080] The above embodiments only illustrate preferred implementation methods, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model.

Claims

1. A floatation device of a TMAH wastewater treatment system, characterized by: It includes a pretreatment tank I, a neutralization reaction tank II, and an air flotation tank III connected in sequence; The bottom plate of the flotation tank III has multiple aeration holes evenly distributed, and the aeration holes are connected to the aeration pipes at the bottom of the flotation tank III. The flotation tank III is circular, and the drainage mechanism (10) is installed inside the flotation tank III. The drainage mechanism (10) can revolve around the axis of the flotation tank III. When the drainage mechanism (10) rotates, it can make the water in the flotation tank III flow in the same direction - which is called the driving flow direction. The drainage mechanism (10) is connected to the neutralization reaction tank II. When water is discharged from the drainage mechanism (10), it can revolve around the axis of the flotation tank III - which is called the drainage flow direction. The direction of the push flow is opposite to that of the drainage flow, so that the water in the flotation tank III remains relatively still.

2. The air floatation device of a TMAH wastewater treatment system according to claim 1, wherein: The lower part of the drainage mechanism (10) extends into the flotation tank III, and the water discharged by the drainage mechanism (10) is discharged from the lower part of the liquid in the flotation tank III.

3. The air flotation device of a TMAH wastewater treatment system according to claim 1 or 2, characterized in that: The flotation tank III is also equipped with a flocculation collection mechanism (20), which is located at the liquid surface of the flotation tank III. The flocculation collection mechanism (20) is in the shape of a drum, and its radial cross section is in the shape of a spiral structure; when the flocculation collection mechanism (20) rotates, it can collect the flocs on the liquid surface in the flotation tank III through the spiral structure; When the flocculation collection mechanism (20) rotates, it can drive the liquid on the surface of the flotation tank Ⅲ to revolve around the axis of the flotation tank Ⅲ. The direction of rotation of the liquid on the surface is called the impurity removal flow direction. The impurity removal flow direction and the drainage flow direction are the same and, when they work together, cancel each other out with the driving flow direction.

4. The air floatation device of a TMAH wastewater treatment system according to claim 3, wherein: The flocculation collection mechanism (20) also revolves around the axis of the flotation tank III, and the direction of revolution and the speed of rotation of the flocculation collection mechanism (20) are the same as the direction of revolution and the speed of rotation of the drainage mechanism (10) revolving around the axis of the flotation tank III.

5. The air floatation device of a TMAH wastewater treatment system according to claim 3, wherein: The air flotation tank Ⅲ is a circular steel tank body (30), and a central cylinder A (31) is welded at the center of the steel tank body (30), and the two together form an annular cavity. A rotatable long base frame (32) is fitted on the central cylinder A (31), with the middle part of the long base frame (32) fitted on the central cylinder A (31), and the two ends of the long base frame (32) resting on the edges of the steel pool body (30) via rollers (33). The rollers (33) are connected to the first drive mechanism. When the first drive mechanism is working, the rollers (33) can roll, thereby allowing the long base frame (32) to rotate around the axis of the floating pool III. A drainage mechanism (10) is fixed on the right side of the long base frame (32), and a flocculation collection mechanism (20) is installed on the left side of the long base frame (32).

6. The air flotation device for a TMAH wastewater treatment system according to claim 5, characterized in that: The drainage mechanism (10) includes an upper water tank (11) and a lower water tank (12). The upper water tank (11) and the lower water tank (12) are fixed on the upper and lower surfaces of the right side of the long base frame (32), respectively. The lower water tank (12) is divided into multiple chambers by multiple arc-shaped partitions (1201), and each chamber is connected to the upper water tank (11) through a corresponding pipe; multiple water holes (1202) are opened at the lower part of the front / rear wall of the lower water tank (12). Water flows from the upper water tank (11) into different chambers of the lower water tank (12) and then is discharged through the water hole (1202). The direction of the water discharged from the water hole (1202) is tangent to the arc of the arc-shaped partition (1201), forming a structure that cancels out the drainage direction and the driving direction.

7. The air flotation device of a TMAH wastewater treatment system according to claim 5, wherein: The flocculation collection mechanism (20) includes a spiral cylinder (21) and an end cylinder (22); The spiral cylinder (21) is made of steel plate rolled into a cylinder shape, and its radial cross section is spiral after rolling. The two ends of the spiral cylinder (21) are closed by end caps, and end cylinders (22) are welded on the end caps. The end cylinders (22) are connected to the central cavity at the axis of the spiral cylinder (21). When the spiral cylinder (21) rotates, it can collect the flocs at the liquid surface through the opening of the spiral cylinder (21), and as the spiral cylinder (21) rotates, the flocs can slide along the spiral wall and gradually accumulate in the central cavity of the spiral cylinder (21).

8. The air floatation device of a TMAH wastewater treatment system according to claim 7, wherein: The long base frame (32) has a large frame hole that runs through the top and bottom. The spiral cylinder (21) is located at the large frame hole, so that when the spiral cylinder (21) rotates, its opening can scoop up the liquid surface. A grooved wheel (23) is fitted at one end of the spiral cylinder (21) at the end cylinder (22), and the grooved wheel (23) is locked at the upper edge of the central cylinder A (31); the other end of the spiral cylinder (21) is mounted on the long base frame (32) via a support seat, and the end cylinder is also connected to the second drive mechanism; when the second drive mechanism is working, it can make the flocculation collection mechanism rotate. Screw shafts are provided in the central cavity of the spiral cylinder (21) and in the end cylinders at the left and right positions. The screw shafts are connected to the third drive mechanism. When the third drive mechanism is working, the flocculated material at the center of the spiral cylinder (21) can be discharged from the end cylinder (22).

9. The air floatation device of a TMAH wastewater treatment system according to claim 5, wherein: The air flotation tank Ⅲ is supported by a support frame, and a central cylinder B (34) is provided inside the central cylinder A (31) of the air flotation tank Ⅲ. There is an annular gap between the central cylinder A (31) and the central cylinder B (34). The lower end of the central cylinder B (34) is connected to the neutralization reaction vessel via a pipe and a pump; The upper end of the central cylinder B (34) is connected to the upper water tank (11) via a universal joint, so that water can enter the upper water tank (11) without affecting the upper water tank (11) from revolving around the axis of the flotation tank III.

10. The air floatation device of a TMAH wastewater treatment system according to claim 9, wherein: The annular gap between the central cylinder A (31) and the central cylinder B (34) is the flocculation chamber, which is connected by the flocculation discharge pipe; The upper part of the outer wall of the flotation tank III is provided with a drainage pipe (35). The bottom of the flotation tank III has a sludge collection trough (36), which is connected to the sludge discharge pipe. A sludge discharge plate is detachably installed on the front / rear wall of the lower water tank (12). When the sludge discharge plate rotates with the lower water tank (12), it can sweep the sludge at the bottom of the flotation tank III into the sludge collection trough (36).

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