Dissolved air flotation scum scraping device

Abstract

The utility model discloses a dissolved air flotation scum scraping device, which belongs to the field of wastewater treatment equipment and comprises an air flotation tank and scum scraping equipment. The air floatation tank is provided with a collecting tank along the radial direction, and one side of the collecting tank is provided with a slope. The scum scraping equipment comprises a scraping arm and a scraping plate, the scraping arm is arranged in the radial direction of the air floatation tank and can circumferentially rotate towards the slope direction around the air floatation tank, the top of the scraping plate is hinged to the scraping arm, and a concave area is formed in the side, pushing scum, of the scraping plate. The scraping plate can rotate relative to the slope through the hinged structure of the scraping plate and the scraping arm, and large interference and resistance cannot be generated between the scraping plate and the slope. And after the scraper rotates, the scum in the concave area can be automatically poured into the collecting tank to be discharged. And the concave area of the scraper can enhance the collection and storage effects of the scum when the scraper revolves. After a large amount of scum is stored in the inner concave area, when the scraping plate is in contact with the slope, the reverse thrust of the scum on the scraping plate is reduced, the scum amount pushed in a single time is increased, and then the scum discharging efficiency is improved.

Description

Technical Field

[0001] The utility model belongs to the field of wastewater treatment equipment, in particular to a dissolved air flotation scum scraping device. Background Art

[0002] Dissolved air flotation equipment is a high-efficiency solid-liquid separation equipment used in water treatment. Its core principle is that the flocculant pre-added in the water to be treated flocculates the suspended matter into large particles, dissolves air in the water to form dissolved air water, and then quickly reduces the pressure to release tiny bubbles in the dissolved air water, attaching the particles in the water to the bubbles. These particles float to the water surface under the action of tiny bubbles to form a scum layer, and the scum is scraped off by the scraping equipment to achieve solid-liquid separation. The flotation scraping equipment is a key equipment in the flotation system. Its main function is to scrape off the scum in the flotation tank efficiently and continuously to ensure the treatment efficiency of the flotation tank and the water quality of the effluent.

[0003] Shallow flotation machine is a type of flotation machine. Its flotation tank is cylindrical, and the scraping equipment rotates around the surface of the circular flotation tank to remove the scum. The commonly used scraping equipment of shallow flotation machine is to collect the scum into the inside of the bucket through the continuous revolution and rotation of the bucket on the water surface and discharge it through the inclined channel inside the bucket. This slag removal method has a good cleaning effect and less cleaning residue, but at the same time, the bucket will also carry a large amount of clean water to discharge with the scum, which makes the subsequent processing process difficult and generates additional energy consumption.

[0004] Another type of scraping equipment for shallow flotation machines consists of scrapers, scraper arms and collection tanks. The collection tanks are arranged radially along the flotation tank. The scraper arms drive the scrapers to revolve around the flotation tank. The rubber part on the scraper pushes the scum toward the collection tank and finally scrapes the scum into the collection tank for discharge. Due to poor wastewater quality and the small area of ​​the scum tank due to site restrictions, the scum will accumulate too thickly. In addition, the rubber part on the scraper is not strong enough, which makes it impossible for the rubber part to scrape the scum into the collection tank, resulting in low scum discharge efficiency. Utility Model Content

[0005] The utility model aims to provide a dissolved air flotation scum scraping device to solve the problems raised in the above-mentioned prior art.

[0006] Provided is a dissolved air flotation scum scraping device, comprising:

[0007] An air flotation tank, wherein the air flotation tank is provided with a collecting tank in a radial direction, and a slope is provided on one side of the collecting tank;

[0008] The scraping device comprises a scraping arm and a scraper. The scraping arm is arranged along the radial direction of the flotation tank and can rotate circumferentially around the flotation tank toward the slope direction. The top of the scraper is hinged to the scraping arm. The scraper pushes one side of the scum to form a concave area.

[0009] Furthermore, the scraper is bent as a whole to form an arc-shaped plate, and the concave area is formed by the concave surface of the arc-shaped plate. When the scraper contacts the slope, the continuous arc structure of the concave surface can naturally flow out the water in the concave area. If there is a sudden turning point, water will remain at the turning point due to the effect of surface tension, which is not conducive to the separation of scum and water.

[0010] Furthermore, the thickness of the scraper gradually increases from the hinged end to the tail end of the scraper. By increasing the material ratio at the tail end of the scraper, the weight of the tail end of the scraper is larger, and the center of gravity of the scraper moves downward. After the center of gravity moves downward, the scraper is not easy to rotate relative to the hinged part under the resistance of the water flow, thereby avoiding the reduction of the scraping effect due to the rotation of the scraper.

[0011] Furthermore, a water filter is provided at the tail end of the scraper. When the scraper contacts the slope, the water mixed with the scum can be filtered out through the water filter, thereby preventing a large amount of clean water from being brought into the collection tank, thereby improving the effect of solid-liquid separation.

[0012] Furthermore, the water filter part is composed of a plurality of filter holes opened along the length direction at the tail end of the scraper, and the aperture of the filter holes ranges from 3mm to 7mm. By controlling the aperture of the filter holes, the scum will not leak out of the filter holes under the action of its own tension, while the water flow can be filtered out smoothly from the filter holes.

[0013] Furthermore, the water filtering part includes a plurality of grooves and a plurality of rollers, wherein the plurality of grooves are arranged along the length direction of the tail end of the scraper, and the plurality of rollers are rotatably connected to the corresponding grooves. To ensure that the rollers can rotate freely, a certain gap is left between the grooves and the rollers, and this gap can be used as a space for water to be filtered out. In addition, after the rollers contact the slope, they can rotate relative to the slope, thereby converting the original sliding friction between the scraper and the slope into rolling friction between the rollers and the slope, thereby preventing wear between the scraper and the slope due to sliding friction, and at the same time reducing the noise generated by the friction between the scraper and the slope.

[0014] Furthermore, after the roller contacts the slope, a gap of 3 mm to 10 mm is left between the tail end of the scraper and the slope. In order to ensure that the scraper and the slope do not interfere with each other when the roller and the slope rotate relative to each other, a certain distance needs to be left between the scraper and the slope. The distance cannot be too small to prevent the scraper and the slope from contacting each other when the outer diameter of the roller decreases due to wear. The distance cannot be too large to prevent a large amount of scum from leaking out of the gap.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] The articulated structure of the scraper and the scraper arm enables the scraper to rotate relative to the slope when it contacts the slope, without causing large interference and resistance between the scraper and the slope. After the scraper rotates, the concave area can face the collection tank, and the scum in the concave area is automatically dumped into the collection tank for discharge. The concave area of ​​the scraper can enhance the collection and storage effect of scum during the revolution of the scraper. After a large amount of scum is stored in the concave area, when the scraper contacts the slope, the reverse thrust of the scum on the scraper is reduced, and the amount of scum pushed in a single time is increased, thereby improving the slag discharge efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present drawings 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 drawings. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0018] Figure 1 It is a structural layout diagram of a dissolved air flotation scum scraping device;

[0019] Figure 2 A schematic diagram of the structure of the scraping equipment provided by the utility model;

[0020] Figure 3 A working state diagram of the scraping equipment provided by the utility model;

[0021] Figure 4 One of the structural schematic diagrams of the scraper provided by the utility model;

[0022] Figure 5 The second structural schematic diagram of the scraper provided by the utility model;

[0023] Figure 6 This is the third structural schematic diagram of the scraper provided by the utility model.

[0024] In the figure: 1, flotation tank; 11, collecting trough; 12, slope; 2, scraper device; 21, scraper arm; 22, scraper; 221, concave area; 222, water filtering part; 2221, filter hole; 2222, groove; 2223, roller. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0026] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0027] However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of substantially the same structures may be omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. In addition, the drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0028] See also Figure 1-Figure 3 As shown, in the embodiment of the utility model, a dissolved air flotation scum scraping device comprises an air flotation tank 1 and a scum scraping device 2. The air flotation tank 1 is provided with a collecting tank 11 in the radial direction, and a slope 12 is provided on one side of the collecting tank 11. The scum scraping device 2 comprises a scraping arm 21 and a scraping plate 22, the scraping arm 21 is provided in the radial direction of the air flotation tank 1 and can rotate circumferentially around the air flotation tank 1 in the direction of the slope 12, the top of the scraping plate 22 is hinged to the scraping arm 21, and the scraping plate 22 pushes one side of the scum to form an inner concave area 221.

[0029] The collecting trough 11 extends radially along the flotation pool 1, and the edge of the collecting trough 11 is higher than the water level of the flotation pool in the flotation pool 1. The scraper arm 21 is driven to rotate by a driving assembly located in the middle of the flotation pool 1, and synchronously drives the scraper 22 to revolve on the surface of the flotation pool during rotation. The scraper 22 is made of metal material and can reduce the deflection rate by its own gravity when subjected to water flow and scum resistance. The concave area 221 of the scraper 22 can take away the scum on the surface of the flotation pool and store it inside the concave area 221 during the movement. The scraper arm 21 and the scraper 22 are hinged by a hinge. When the scraper 22 moves to contact the slope 12, since the height of the scraper arm 21 remains unchanged, the scraper 22 will rotate relative to the scraper arm 21, so that the concave area 221 gradually faces downward until the concave area 221 faces the inside of the collecting trough 11, and the scum automatically falls into the collecting trough 11 and is discharged under the action of its own gravity. When the scraper 22 moves on the slope 12 , the water in the concave area 221 will automatically drain from the bottom and both sides of the scraper 22 , and the drainage time is determined by the travel time of the scraper 22 on the slope 12 .

[0030] The shape of the scraper 22 can be the same as that of the channel steel with multiple corners, so as to form a concave area 221 with a concave area. Specifically, the scraper 22 is composed of an arc-shaped plate formed by bending as a whole, and the concave part of the concave area 221 is a continuous concave curved surface. The continuous concave curved surface is conducive to destroying the tension of water and allowing the water flow to be discharged smoothly.

[0031] See also Figure 4 As shown, the thickness of the scraper 22 gradually increases from the hinged end to the tail end of the scraper 22. By adjusting the material distribution of the scraper 22, the weight of the tail end of the scraper 22 is greater than the weight of the hinged end, and the posture of the scraper 22 is stabilized by moving the center of gravity downward, so that the concave area 221 will not deflect at a large angle relative to the scraper arm 21 under the action of resistance after receiving a large amount of scum, thereby preventing a large amount of scum from leaking out and causing a decrease in scum scraping efficiency.

[0032] See also Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown, a water filter 222 is provided at the tail end of the scraper 22. The water filter 222 filters out the water located in the concave area 221 and the scum through a specific structure, thereby enhancing the water discharge effect when the scraper 22 moves on the slope 12 and reducing the water flow carried by the scum when entering the collection tank 11.

[0033] In one embodiment, see Figure 3 and Figure 5 As shown, the water filter part 222 is composed of a plurality of filter holes 2221 opened along the length direction at the tail end of the scraper 22, and the water flow is filtered out from here through the through structure of the filter holes 2221. The filter hole 2221 can be a through hole that penetrates the entire structure of the scraper 22, or a slot hole formed by the inward depression of the edge of the scraper 22. The through hole does not contact the slope 12, and the slot hole contacts the slope 12. The aperture range of the filter hole 2221 is 3mm to 7mm. The filter hole 2221 has an aperture of at least 3mm to prevent the water from being unable to be filtered out from the filter hole 2221 under the tension of the water and the blockage of the scum; and the aperture of the filter hole 2221 cannot be greater than 7mm to prevent a large amount of scum from leaking from the filter hole 2221.

[0034] In one embodiment, see Figure 3 and Figure 6As shown, the water filter 222 includes a plurality of grooves 2222 and a plurality of rollers 2223. The plurality of grooves 2222 are arranged along the length direction of the tail end of the scraper 22, and the plurality of rollers 2223 are rotatably connected to the inside of the corresponding grooves 2222. The grooves 2222 are formed by the inward depression of the tail end of the scraper 22. The rollers 2223 are arranged inside the grooves 2222 through a rotating shaft, and rotate relative to the grooves 2222 through the rotating shaft. The water carried by the scum can be filtered out through the gap between the grooves 2222 and the rollers 2223 and the gap between the grooves 2222 and the bottom of the slope 12.

[0035] In addition, after the roller 2223 contacts the slope 12, it can rotate relative to the slope 12, thereby converting the original sliding friction between the scraper 22 and the slope 12 into rolling friction between the roller 2223 and the slope 12, preventing wear between the scraper 22 and the slope 12 due to sliding friction, and at the same time reducing the noise generated by the friction between the scraper 22 and the slope 12.

[0036] After the roller 2223 contacts the slope 12, a gap of 3 mm to 10 mm is left between the tail end of the scraper 22 and the slope 12. The gap distance is greater than 3 mm to prevent water from being unable to filter out of the gap due to water tension and scum blockage; and the gap distance cannot be greater than 10 mm to prevent scum from leaking a large amount of the gap.

[0037] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A dissolved air flotation scum scraping device, characterized in that: include: An air flotation tank (1), wherein the air flotation tank (1) is provided with a collecting tank (11) in a radial direction, and a slope (12) is provided on one side of the collecting tank (11); The scraping device (2) comprises a scraping arm (21) and a scraping plate (22), wherein the scraping arm (21) is arranged along the radial direction of the flotation tank (1) and can rotate circumferentially around the flotation tank (1) in the direction of the slope (12), the top of the scraping plate (22) is hinged to the scraping arm (21), and the scraping plate (22) pushes one side of the scum to form an inner concave area (221).

2. A dissolved air flotation scum scraping device according to claim 1, characterized in that: The scraper (22) is integrally bent to form an arc-shaped plate, and the concave area (221) is formed by the concave surface of the arc-shaped plate.

3. A dissolved air flotation scum scraping device according to claim 1, characterized in that: The thickness of the scraper (22) gradually increases from the hinged end to the tail end of the scraper (22).

4. A dissolved air flotation scum scraping device according to claim 1, characterized in that: The tail end of the scraper (22) is provided with a water filtering portion (222).

5. A dissolved air flotation scum scraping device according to claim 4, characterized in that: The water filtering portion (222) is composed of a plurality of filter holes (2221) opened along the length direction at the tail end of the scraper (22), and the aperture of the filter holes (2221) ranges from 3 mm to 7 mm.

6. A dissolved air flotation scum scraping device according to claim 4, characterized in that: The water filtering portion (222) comprises a plurality of grooves (2222) and a plurality of rollers (2223); the plurality of grooves (2222) are arranged along the length direction of the tail end of the scraper (22); and the plurality of rollers (2223) are rotatably connected to the inside of corresponding grooves (2222).

7. A dissolved air flotation scum scraping device according to claim 6, characterized in that: After the roller (2223) contacts the slope (12), a gap of 3 mm to 10 mm is left between the rear end of the scraper (22) and the slope (12).

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