A sewage surface foam and scum treatment device and method

Abstract

The present invention discloses a sewage surface foam and scum treatment device and method, which includes a pretreatment tank and an oxidation treatment tank; the pretreatment tank includes a sewage area and a filtration area, a water outlet is provided on the partition board, and a scum discharge pipe that is inclined and has its upper end passing through the sewage area and communicating with the outside is arranged at the water outlet, and the bottom of the scum discharge pipe is of a filter plate structure; the filtration area communicates with the oxidation treatment tank; a foam and scum discharge device is arranged at the upper end of the scum discharge pipe, and the foam and scum discharge device includes a driving rotating cylinder, a plurality of scraping plates are arranged on the outer surface of the driving rotating cylinder along the circumferential direction, the end of the scraping plate is in an L-shaped hook structure, a discharge groove is formed on the outer wall of the driving rotating cylinder beside the scraping plate, and the bottom surface of the discharge groove is inclined; the driving rotating cylinder can rotate to drive the scraping plate to move to the outlet of the scum discharge pipe to remove the foam and scum. By improving the water outlet structure of the pretreatment tank and simultaneously arranging a foam and scum discharge device with an improved structure, the present invention can realize the collection and defoaming treatment of the foam and scum while scraping.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and more particularly, to a device and method for treating surface foam and scum of sewage. Background Art

[0002] Before sewage is treated, its surface usually contains a large amount of substances such as foam, scum, and grease. If these substances are not treated in the early stage, more foam, scum, and grease will be intercepted on the surface of the biochemical tank, thereby hindering the entry of oxygen into the mixed liquid of the aeration tank, resulting in a decrease in oxygenation efficiency or an increase in suspended solids and COD in the effluent of the secondary sedimentation tank, increasing the operating pressure of advanced treatment, and affecting the visual sense of the tank surface and the stable up-to-standard discharge of the effluent quality.

[0003] Therefore, it is very necessary to treat substances such as surface foam, scum, and grease in sewage before it enters the oxidation treatment tank. Currently, the conventional treatment method is to set a foam scraper at the water inlet between the pretreatment tank and the oxidation treatment tank to scrape it off. However, the removal effect is poor, and an additional structure is required to transport, collect, and perform subsequent defoaming treatment on the scraped foam.

[0004] In view of this, the present application is specifically proposed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing treatment method for foam, scum, and grease is to set a foam scraper at the water inlet between the pretreatment tank and the oxidation treatment tank to scrape it off. However, the removal effect is poor, and an additional structure is required to transport, collect, and perform subsequent defoaming treatment on the scraped foam. The purpose is to provide a device and method for treating surface foam and scum of sewage. By improving the water outlet structure of the pretreatment tank and simultaneously setting a foam and scum discharge device with an improved structure, it is possible to achieve the collection and defoaming treatment of foam and scum while scraping.

[0006] The present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides a device for treating surface foam and scum of sewage, including a pretreatment tank and an oxidation treatment tank;

[0008] The pretreatment tank includes a sewage area and a filtration area separated by a partition. The partition is provided with a water outlet, and an inclined upward scum discharge pipe is arranged at the water outlet. The scum discharge pipe is located in the sewage area and its upper end passes through the sewage area and communicates with the outside. The bottom of the scum discharge pipe is a filter plate structure, and the water in the sewage area passes through the filter plate structure and enters the filtration area;

[0009] The filtration area is connected to the oxidation treatment tank;

[0010] A foam and scum discharging device is provided at the upper end outlet of the scum discharge pipe. The foam and scum discharging device includes a driving rotating cylinder arranged parallel to the outlet of the scum discharge pipe. A plurality of scraping plates are sequentially arranged on the outer surface of the driving rotating cylinder along the circumferential direction. The end of the scraping plate is in an L-shaped hook structure. A discharge groove is formed in the outer wall of the driving rotating cylinder beside the scraping plate. The bottom surface of the discharge groove is inclined along the axial direction of the driving rotating cylinder. The driving rotating cylinder can rotate around its own axis, driving the scraping plate to move to the outlet of the scum discharge pipe to remove the foam and scum.

[0011] Currently, a water passing opening is provided between the pretreatment tank and the oxidation treatment tank. Then, an interception groove is arranged at the water passing opening, and a scraping plate is arranged above the interception groove. The sewage moves along the direction of the interception groove, so that under the action of the moving direction, the surface foam and scum and the sewage below are separated by the interception groove. The surface foam and scum remain on the interception groove, and the other sewage enters the oxidation treatment tank from below the interception groove. This structure has the problems that the foam and scum cannot be removed cleanly, and the foam and scum on the interception groove are also prone to flow back under the impact of the sewage flow.

[0012] The foam and scum treatment device of the present invention divides the pretreatment tank into two areas, and uses the filtration area as the transition area between the pretreatment tank and the oxidation treatment tank. The non-foam and scum part at the lower part of the sewage passes through the lower filter plate structure of the scum discharge pipe and enters the filtration area and then into the oxidation treatment tank, avoiding the surface foam and scum from entering the oxidation treatment tank along the water flow direction. The scum discharge pipe structure is arranged obliquely upward, and the filter plate structure is much lower than the upper end opening of the scum discharge pipe. In this way, the water surface height of the sewage can always be maintained at a position close to the upper end outlet of the scum discharge pipe. On the one hand, it avoids the foam and scum covering the filter plate structure at the water surface height at the filter plate structure and affecting the water passing effect. On the other hand, the inclined structure also restricts the movement direction of the foam and scum on the water surface in the scum discharge pipe to be from bottom to top, without a downward impact force, which can ensure the independence of the movement of the scum foam and the water passing of the bottom filter plate structure in the movement direction, and ensure the full separation of the sewage and the foam and scum.

[0013] Since sewage continuously enters the pretreatment tank, the water surface of the pretreatment can continuously fluctuate. Under the action of the water flow fluctuation, the foam scum can be discharged back and forth at the outlet of the scum discharge pipe, driving the rotating cylinder to drive the scraper to rotate. When the L-shaped hook structure at the end of the scraper rotates from bottom to top to the outlet of the scum discharge pipe, it can scrape substances such as foam scum into the L-shaped hook structure. The scraper continues to rotate upward, and the foam scum on the scraper can flow back along the scraper into the discharge tank, and then be discharged into the collection device from the inclined discharge tank. Multiple scrapers repeat the above operations, and can continuously scrape and collect the foam scum overflowing from the scum discharge pipe. In the foam scum treatment device of the present invention, the scraper is completely separated and independent from the entire sewage, and only contacts the foam scum at the opening of the scum discharge pipe. Therefore, relatively speaking, the sewage will not generate a continuous impact force on the scraper, and there will be no situation of foam scum backflow. The foam scum in the pretreatment tank of this application is macroscopically stationary and always remains at the water surface height position, and will not impact the foam discharge device along with the water flow. Microscopically, the foam scum on the water surface will fluctuate under the action of the lower water body, so as to gush out and retreat to the upper opening of the scum discharge pipe at intervals in a way similar to tides, realizing the intermittent discharge of foam scum.

[0014] In a specific embodiment, the scraper has a hollow structure and includes a fixed plate and a movable plate. The fixed plate is vertically installed directly above the discharge tank. One end of the movable plate is movably sleeved on the fixed plate, and the movable plate can be retracted into or extended out of the fixed plate along the radial direction of the driving rotating cylinder under the action of its own gravity; the other end of the movable plate is in an L-shaped hook structure, and the end opening is communicated with the discharge tank.

[0015] The scraper of the present invention is set to have a hollow structure, so that the foam scum can enter the interior from the end opening of the scraper, and then flow into the discharge tank along the internal hollow structure, that is, the foam scum is wrapped inside the scraper for transportation, avoiding flowing to other places during rotation; at the same time, the scraper is set to have a double-jointed structure. When the scraper scrapes the foam scum and continues to move upward to the highest point, the moving plate can slowly slide into the fixed plate under its own gravity, gradually reducing the distance between the L-shaped hook structure and the fixed plate. When reaching the highest point, the moving plate slides completely into the fixed plate in an instant, and the impact force generated between the moving plate and the fixed plate can shake off the foam scum adhering to the inside of the moving plate, enabling it to be fully discharged. Subsequently, after the scraper continues to rotate to the lowest point, the moving plate completely extends out of the fixed plate under the action of gravity to perform the next scraping operation. The present invention uses a clever rotating structure to enable the scraper to transport the foam scum to the collection device while scraping the foam scum without an additional transportation structure. At the same time, by utilizing the self-gravity of the scraper with a double-layer telescopic structure, the foam scum can be efficiently discharged, avoiding adhesion to the inside of the scraper and affecting the subsequent scraping and transportation of the foam scum. In addition, by setting the scraper to have a hollow structure, the end opening has a certain siphon effect, which is more conducive to the adsorption of foam.

[0016] In a specific embodiment, the water outlet has a horizontal long strip structure, the internal height dimension of the scum discharge pipe gradually decreases from the lower end to the upper end, and the inclination angle of the bottom plate of the scum discharge pipe is greater than the inclination angle of the top plate.

[0017] By setting the scum discharge pipe structure with a larger bottom and a smaller top and the inclination angle of the bottom being greater than that of the top, the present invention can first ensure that there is a sufficient height difference between the filter plate structure and the upper end of the scum discharge pipe. Secondly, this structure can buffer the impact force of the foam scum during the fluctuation process, thereby controlling the overflow amount of the foam scum.

[0018] A cleaning pool is provided below the driving rotating cylinder beside the upper end outlet of the scum discharge pipe, and the cleaning pool is filled with cleaning water.

[0019] The present invention provides a cleaning pool below the foam scum discharge device. When the scraper moves to the bottom, its end can extend into the water in the cleaning pool for simple wet cleaning, removing a small amount of residual foam scum at the end, and preventing the foam scum scraped by the scraper subsequently from aggregating and adsorbing with the residual foam scum from the previous time, which affects the discharge effect.

[0020] In a specific embodiment, the opening surface of the L-shaped hook structure at the end of the moving plate is an inclined surface, so that the end is a conical structure. In the present invention, the opening surface of the L-shaped hook structure is arranged as an inclined surface structure. Firstly, the inclined surface structure can increase the contact area between the L-shaped hook structure and the foam scum, enabling it to smoothly enter the internal hollow structure. Secondly, after setting the opening inclined surface to increase the area, the height at the entrance of the inclined surface can be designed to be relatively narrow. In this way, when the foam scum enters the opening inclined surface and reaches the entrance, the narrow entrance can play a certain role in defoaming. At the same time, using the siphon principle, all the foam on the opening inclined surface can be sucked into the interior, avoiding remaining at the opening inclined surface.

[0021] In a specific embodiment, in the sewage area, a wave-pushing shaft is arranged at the extending direction of the lower end of the scum discharge pipe. The wave-pushing shaft can rotate around its own axis, and a wave-pushing plate is vertically connected to the wave-pushing shaft.

[0022] In order to generate more regular fluctuations on the water surface at the scum discharge pipe, in this application, by setting the wave-pushing shaft and the wave-pushing plate, when the wave-pushing plate moves towards the scum discharge pipe, the sewage below is pushed into the scum discharge pipe to generate an outward impact force, causing the foam scum to overflow from the outlet of the scum discharge pipe. When the wave-pushing plate moves away from the scum discharge pipe, the water surface in the scum discharge pipe retreats smoothly until the wave-pushing plate moves towards the scum discharge pipe again. By continuously performing the above operations, fluctuations are generated at a certain frequency interval at the upper end opening of the scum discharge pipe, corresponding to multiple scraping plates, to achieve continuous removal of the foam scum.

[0023] In a specific embodiment, the wave-pushing plate is in an arc structure, which can increase the contact area with the sewage, making the generated driving force more concentrated and stable.

[0024] In a specific embodiment, a medicine spraying pipe is arranged above the upper end outlet of the scum discharge pipe. The medicine spraying pipe can spray the adsorbed medicine powder into the opening of the moving plate. The adsorbed medicine powder is magnesium aluminum silicate-coated poly(lactic-co-glycolic acid) microspheres, which can be used to adsorb foam scum and grease to form a gel-like structure.

[0025] Substances such as foam and grease existing on the sewage surface are all substances with strong adhesiveness. Therefore, there will still be a certain amount of grease and foam substances remaining on the scraping plate. Therefore, in the present invention, by spraying the adsorbed medicine powder of magnesium aluminum silicate-coated poly(lactic-co-glycolic acid) microspheres on the scraping plate, the outer layer of magnesium aluminum silicate has a large specific surface area and a porous structure, and can adsorb oily substances several times its own weight. Therefore, after the foam grease is scraped onto the scraping plate, magnesium aluminum silicate can quickly adsorb the grease and foam to form a continuously thickening gel-like substance. The gel substance after adsorbing the grease and foam has good fluidity and can easily slide off the inner wall of the scraping plate and flow into the discharge groove. Poly(lactic-co-glycolic acid) is a low-molecular-weight biodegradable material with a fast degradation rate and no pollution to the environment, and also solves the problem of defoaming of subsequent foam.

[0026] Among them, the preparation method of magnesium aluminum silicate-coated poly (lactic-co-glycolic acid) microspheres is as follows: tetraethyl orthosilicate, hydrochloric acid and water are mixed and stirred to form a gel, a solution of aluminum sulfate and magnesium sulfate is added dropwise, stirred and mixed, and ammonia water is added dropwise to obtain a magnesium aluminum silicate sol; then the poly (lactic-co-glycolic acid) microsphere powder is added to the magnesium aluminum silicate sol, stirred and mixed, aged, washed with water, calcined, and finally ball-milled to obtain a powdery material.

[0027] In a specific embodiment, a buffer interface pipe is arranged at the upper end opening of the scum discharge pipe, and the buffer interface pipe is perpendicular to the outer side wall of the pretreatment tank. By arranging the buffer interface pipe to extend the length and angle of the upper end opening of the scum discharge pipe, it is more beneficial to the coordination and connection between the discharge of foam scum and the scraping by the scraper.

[0028] In a specific embodiment, the buffer interface pipe is arranged to incline downward, forming a structure similar to an inverted V shape with the scum discharge pipe. The inclination angle of the upper plate of the buffer interface pipe is greater than that of the lower plate, and the lower plate of the buffer interface pipe is hinged to the side wall of the tank at the outlet of the scum discharge pipe. The lower plate of the buffer interface pipe can contact the scraper and rotate upward under the drive of the scraper, and can freely fall back to the original position after separating from the scraper.

[0029] The buffer interface pipe of the present invention is arranged to incline downward. Firstly, it can extend the movement path of the overflowing foam by inclination. At the same time, after the foam waste residue moves through the inclined buffer interface pipe, it can directly "fall" into the scraper; the structure of the buffer interface pipe with a large upper part and a small lower part can buffer the impact force of the overflowing foam, so that it can fall onto the scraper in a concentrated manner with a smaller area; finally, the present invention sets the lower plate of the buffer interface pipe as a hinged structure. When the scraper rotates upward to the lower plate, the foam waste residue falls from the buffer interface pipe onto the scraper. The contact between the scraper and the lower plate drives it to rotate upward (it can also move to contact the end of the upper plate to close the buffer interface pipe), so as to apply a reverse driving force to the foam scum about to overflow the lower plate to make it return to the scum discharge pipe. As the scraper continues to rotate and separates from the lower plate, the lower plate falls back to its original position, and the floating scum foam of the next fluctuation overflows into the buffer interface pipe and falls onto the next scraper.

[0030] Secondly, the present invention provides a method for treating surface foam scum of sewage, which is characterized by including the following steps:

[0031] (1) Continuously introduce sewage into the sewage area until the water surface is flush with the upper end opening of the scum discharge pipe. Control the water inlet speed and water outlet speed of the sewage area to keep the water surface height of the sewage area. The sewage enters the filtration area through the filter plate structure, and the surface foam scum and grease of the sewage float on the water surface of the sewage area;

[0032] (2) Start the drive drum of the foam scum discharging device, and at the same time start the wave-pushing shaft. During the rotation of the wave-pushing plate, the sewage at the lower part is pushed towards the scum discharge pipe. A fluctuation is generated on the water surface in the scum discharge pipe, and the foam scum and grease on the surface overflow towards the outlet of the scum discharge pipe. The scraper rotating to the outlet of the scum discharge pipe takes away the overflowed foam scum and grease;

[0033] (3) The foam scum and grease enter the end opening of the scraper. The scraper continues to move upward, and the foam scum and grease in the scraper flow into the discharge trough along the internal hollow structure and are discharged and collected through the discharge trough;

[0034] (4) The scraper moves downward into the clear water tank to clean the residual waste on the surface. The scraper continues to move upward and repeats the above steps to discharge the foam scum.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] 1. For a sewage surface foam scum treatment device and method provided by an embodiment of the present invention, the pretreatment tank is set into two areas. The part of the sewage without foam scum at the lower part passes through the filter plate structure below the scum discharge pipe and enters the filtration area and then into the oxidation treatment tank, avoiding the surface foam scum from entering the oxidation treatment tank along the water flow direction. The scum discharge pipe structure is arranged to incline upward, and the water surface height of the sewage can always be maintained at a position close to the upper end outlet of the scum discharge pipe. On the one hand, it avoids the foam scum covering the filter plate structure at the filter plate structure and affecting the water passing effect. On the other hand, it restricts the movement direction of the foam scum on the water surface in the scum discharge pipe to be from bottom to top, without a downward impact force, which can ensure the independence of the movement directions of the scum foam movement and the water passing through the bottom filter plate structure, and ensure the full separation of sewage and foam scum;

[0037] 2. For a sewage surface foam scum treatment device and method provided by an embodiment of the present invention, the foam scum is discharged back and forth at the outlet of the scum discharge pipe. When the L-shaped hook structure at the end of the scraper rotates from bottom to top to the outlet of the scum discharge pipe, it can scrape substances such as foam scum into the L-shaped hook structure. The scraper is completely separated and independent from the entire sewage, and only contacts the foam scum at the opening of the scum discharge pipe. Therefore, relatively speaking, the sewage will not generate a continuous impact force on the scraper, and there will be no situation of foam scum backflow;

[0038] 3. For a sewage surface foam scum treatment device and method provided by an embodiment of the present invention, from a macroscopic perspective, the foam scum is stationary and always remains at the water surface height position and will not impact the foam discharging device along with the water flow. From a microscopic perspective, the foam scum on the water surface will generate fluctuations under the action of the lower water body, and thus gush out and retreat towards the upper opening of the scum discharge pipe at intervals in a way similar to tides, realizing the intermittent discharge of foam scum;

[0039] 4. A sewage surface foam and scum treatment device and method provided by an embodiment of the present invention utilize a clever rotating structure to enable the scraper to transport the foam and scum to the collection device while scraping the foam and scum without the need for an additional transportation structure. At the same time, by utilizing the self-gravity of the scraper with a double-layer telescopic structure, the foam and scum can be efficiently discharged, avoiding adhesion inside the scraper and affecting the subsequent scraping and transportation of the foam and scum. At the same time, the scraper is set as a hollow structure, and the end opening has a certain siphon effect, which is more conducive to the adsorption of foam;

[0040] 5. A sewage surface foam and scum treatment device and method provided by an embodiment of the present invention set the opening surface of the L-shaped hook structure as an inclined surface structure. Firstly, the inclined surface structure can increase the contact area between the L-shaped hook structure and the foam and scum, enabling it to smoothly enter the internal hollow structure. Secondly, after setting the opening inclined surface to increase the area, the height at the inclined surface entrance can be designed to be relatively narrow. In this way, when the foam and scum enter the opening inclined surface and reach the entrance, the narrow entrance can play a certain defoaming role, and at the same time, using the siphon principle, all the foam on the opening inclined surface can be sucked into the interior, avoiding residue at the opening inclined surface;

[0041] 6. A sewage surface foam and scum treatment device and method provided by an embodiment of the present invention spray an adsorption powder of magnesium aluminum silicate-coated poly(lactic-co-glycolic acid) microspheres on the scraper. The outer layer of magnesium aluminum silicate has a large specific surface area and a porous structure, and can adsorb oily substances multiple times its own weight. Therefore, after the foam grease is scraped onto the scraper, magnesium aluminum silicate can quickly adsorb the grease and foam to form a continuously thickening gel-like substance. The gel substance after adsorbing the grease and foam has good fluidity and can easily slide off the inner wall of the scraper and flow into the discharge tank. Poly(lactic-co-glycolic acid) is a low-molecular-weight biodegradable material with a fast degradation rate and no pollution to the environment, and also solves the problem of subsequent defoaming of the foam. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1 It is a three-dimensional schematic diagram of the sewage surface foam and scum treatment device provided by an embodiment of the present invention;

[0044] Figure 2 It is a front sectional view of the sewage surface foam and scum treatment device provided by an embodiment of the present invention;

[0045] Figure 3 Partial front sectional view of the sewage surface foam and scum treatment device provided by the embodiment of the present invention;

[0046] Figure 4 Schematic structural diagram of the driving rotating cylinder provided by the embodiment of the present invention;

[0047] Figure 5 Schematic structural diagram of the scraper provided by the embodiment of the present invention;

[0048] Figure 6 Schematic structural diagram of the working state of the driving rotating cylinder provided by the embodiment of the present invention;

[0049] Figure 7 Schematic structural diagram of the buffer interface pipe provided by the embodiment of the present invention.

[0050] Reference numerals and corresponding component names:

[0051] 1 - Pretreatment tank, 2 - Oxidation treatment tank, 3 - Sewage area, 4 - Filtration area, 5 - Water outlet, 6 - Scum discharge pipe, 7 - Driving rotating cylinder, 8 - Scraper, 9 - Discharge trough, 10 - Fixed plate, 11 - Moving plate, 12 - Cleaning tank, 13 - Wave - pushing shaft, 14 - Wave - pushing plate, 15 - Medicine spraying pipe, 16 - Buffer interface pipe, 17 - Partition board. Detailed implementation manners

[0052] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the embodiments and the drawings. The illustrative embodiments and descriptions thereof of the present invention are only used to explain the present invention and do not limit the present invention.

[0053] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that the present invention does not have to employ these specific details. In other embodiments, well - known structures are not specifically described in order to avoid obscuring the present invention.

[0054] Throughout the specification, references to "an embodiment", "embodiments", "an example", or "examples" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Thus, the phrases "an embodiment", "embodiments", "an example", or "examples" that appear throughout the specification do not necessarily all refer to the same embodiment or example. In addition, the particular features, structures, or characteristics may be combined in any suitable combination and / or sub - combination in one or more embodiments or examples. Furthermore, those of ordinary skill in the art should understand that the diagrams provided herein are for illustrative purposes only and are not necessarily drawn to scale. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0055] In the description of the present invention, the orientation or positional relationship indicated by terms such as "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "high", "low", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present invention.

[0056] Embodiment 1

[0057] As Figures 1 - 7 shown, an embodiment of the present invention provides a sewage surface foam and scum treatment device and method, including a pretreatment tank 1 and an oxidation treatment tank 2;

[0058] The pretreatment tank 1 includes a sewage area 3 and a filtration area 4 separated by a partition 17. The partition 2 is provided with a water outlet 5. An inclined upward scum discharge pipe 6 is arranged at the water outlet 5. The scum discharge pipe 6 is located in the sewage area 3 and its upper end passes through the sewage area 3 and communicates with the outside. The bottom of the scum discharge pipe 6 is a filter plate structure, and the water in the sewage area 3 enters the filtration area 4 after being filtered by the filter plate structure;

[0059] The filtration area 4 is communicated with the oxidation treatment tank 2;

[0060] A foam and scum discharge device is arranged at the upper end outlet of the scum discharge pipe 6. The foam and scum discharge device includes a driving rotating cylinder 7 arranged in parallel with the outlet of the scum discharge pipe 6. A plurality of scraping plates 8 are sequentially arranged on the outer surface of the driving rotating cylinder 7 along the circumferential direction. The end of the scraping plate 8 is an L - hook - shaped structure. A discharge groove 9 is formed on the outer wall of the driving rotating cylinder 7 beside the scraping plate 8. The bottom surface of the discharge groove 9 is inclined along the axial direction of the driving rotating cylinder 7. The driving rotating cylinder 7 can rotate around its own axis, driving the scraping plate 8 to move to the outlet of the scum discharge pipe 6 to remove the foam and scum.

[0061] At present, a water passing port is arranged between the pretreatment pool and the oxidation treatment pool, and then an interception tank is arranged at the water passing port, and a scraper is arranged above the interception tank. The sewage moves along the direction of the interception tank, so that under the action of the moving direction, the surface foam scum and the sewage below are separated by the interception tank. The surface foam scum remains on the interception tank, and the other sewage enters the oxidation treatment pool from below the interception tank. This structure has the problems that the foam scum cannot be removed completely, and the foam scum on the interception tank is also prone to flow back under the impact of the sewage flow.

[0062] The foam scum treatment device of the present invention sets the pretreatment pool into two areas, and uses the filtration area as the transition area between the pretreatment pool and the oxidation treatment pool. The part of the sewage without foam scum at the lower part passes through the filter plate structure below the scum discharge pipe and enters the filtration area and then into the oxidation treatment pool, avoiding the surface foam scum from entering the oxidation treatment pool along the water flow direction. The scum discharge pipe structure is arranged obliquely upward, and the filter plate structure is much lower than the upper end opening of the scum discharge pipe. In this way, the water surface height of the sewage can always be kept close to the position of the upper end outlet of the scum discharge pipe. On the one hand, it avoids the water surface height at the filter plate structure causing the foam scum to cover the filter plate structure and affecting the water passing effect. On the other hand, the inclined structure also limits the movement direction of the foam scum on the water surface in the scum discharge pipe to be from bottom to top, without a downward impact force, which can ensure the independence of the movement of the scum foam and the water passing of the bottom filter plate structure in the movement direction, and ensure the full separation of the sewage and the foam scum.

[0063] Since the sewage continuously enters the pretreatment pool, the water surface of the pretreatment can continuously fluctuate. Under the action of the water flow fluctuation, the foam scum can be discharged back and forth at the outlet of the scum discharge pipe, driving the rotating drum to drive the scraper to rotate. When the L-shaped hook structure at the end of the scraper rotates from bottom to top to the outlet of the scum discharge pipe, it can scrape substances such as foam scum into the L-shaped hook structure. The scraper continues to rotate upward, and the foam scum on the scraper can flow back along the scraper into the discharge tank, and then be discharged into the collection device from the inclined discharge tank. Multiple scrapers repeat the above operations, and can continuously scrape and collect the foam scum overflowing from the scum discharge pipe. In the foam scum treatment device of the present invention, the scraper is completely separated and independent from the whole sewage, and only contacts the foam scum at the opening of the scum discharge pipe. Therefore, relatively speaking, the sewage will not generate a continuous impact force on the scraper, and there will be no situation of foam scum flowing back. From a macroscopic perspective, the foam scum in the pretreatment pool of this application is stationary and always remains at the water surface height position, and will not impact the foam discharge device along with the water flow. From a microscopic perspective, the foam scum on the water surface will fluctuate under the action of the lower water body, so as to gush out and retreat to the upper opening of the scum discharge pipe at intervals in a way similar to the tide, realizing the intermittent discharge of the foam scum.

[0064] In a specific embodiment, the scraper 8 has a hollow structure and includes a fixed plate 10 and a movable plate 11. The fixed plate 10 is vertically installed directly above the discharge groove 9. One end of the movable plate 11 is movably sleeved on the fixed plate 10, and the movable plate 11 can be retracted into or extended out of the fixed plate 10 along the radial direction of the driving drum 7 under the action of its own gravity. The other end of the movable plate 11 has an L-shaped hook structure, and the end opening is communicated with the discharge groove 9.

[0065] In the present invention, the scraper is set to have a hollow structure, so that the foam scum can enter the interior from the end opening of the scraper, and then flow into the discharge groove along the internal hollow structure, that is, the foam scum is wrapped inside the scraper for transportation, avoiding flowing to other places during rotation. At the same time, the scraper is set to have a double-joint structure. When the scraper scrapes the foam scum and continues to move upward to the highest point, the movable plate can slowly slide into the fixed plate under the action of its own gravity, gradually reducing the distance between the L-shaped hook structure and the fixed plate. When reaching the highest point, the movable plate completely slides into the fixed plate in an instant, and the impact force generated between the movable plate and the fixed plate can shake off the foam scum adhered to the inside of the movable plate, enabling it to be fully discharged. Subsequently, after the scraper continues to rotate to the lowest point, the movable plate completely extends out of the fixed plate under the action of gravity for the next scraping operation. The present invention uses a clever rotating structure to enable the scraper to transport the foam scum to the collection device while scraping the foam scum without an additional transportation structure. At the same time, by utilizing the self-gravity of the scraper with a double-layer telescopic structure, the foam scum can be efficiently discharged, avoiding adhesion to the inside of the scraper and affecting the subsequent scraping and transportation of the foam scum. In addition, by setting the scraper to have a hollow structure, the end opening has a certain siphon effect, which is more conducive to the adsorption of foam.

[0066] In a specific embodiment, the water outlet 5 has a horizontal long strip structure, the internal height dimension of the scum discharge pipe 6 gradually decreases from the lower end to the upper end, and the inclination angle of the bottom plate of the scum discharge pipe 6 is greater than the inclination angle of the top plate.

[0067] By setting the scum discharge pipe structure with a larger bottom and a smaller top and the inclination angle of the bottom being greater than that of the top, the present invention can first ensure that there is a sufficient height difference between the filter plate structure and the upper end of the scum discharge pipe. Secondly, this structure can buffer the impact force of the foam scum during the fluctuation process, thereby controlling the overflow amount of the foam scum.

[0068] A cleaning pool 12 is arranged below the driving drum 7 beside the upper end outlet of the scum discharge pipe 6, and the cleaning pool 12 is filled with cleaning water.

[0069] A cleaning pool is arranged below the foam scum discharging device of the present invention. When the scraper moves to the bottom, its end can extend into the water in the cleaning pool for simple wet cleaning, removing a small amount of residual foam scum at the end, and preventing the foam scum scraped by the scraper later from aggregating and adsorbing with the residual foam scum from the previous time, thus affecting the discharging effect.

[0070] In a specific embodiment, the opening surface of the L-shaped hook structure at the end of the moving plate 11 is an inclined surface, making the end a conical structure. In the present invention, the opening surface of the L-shaped hook structure is set as an inclined surface structure. Firstly, the inclined surface structure can increase the contact area between the L-shaped hook structure and the foam scum, enabling it to smoothly enter the internal hollow structure. Secondly, after setting the opening inclined surface to increase the area, the height at the entrance of the inclined surface can be designed to be relatively narrow. When the foam scum enters the opening inclined surface and reaches the entrance, the narrow entrance can play a certain role in defoaming. At the same time, using the siphon principle, all the foam on the opening inclined surface can be sucked into the interior, avoiding remaining at the opening inclined surface.

[0071] In a specific embodiment, in the sewage area 3, a wave-pushing shaft 13 is arranged at the extending direction of the lower end of the scum discharge pipe 6. The wave-pushing shaft 13 can rotate around its own axis, and a wave-pushing plate 14 is vertically connected to the wave-pushing shaft 13.

[0072] In order to generate more regular fluctuations on the water surface at the scum discharge pipe, in this application, by setting the wave-pushing shaft and the wave-pushing plate, when the wave-pushing plate moves towards the scum discharge pipe, the sewage below is pushed into the scum discharge pipe to generate an outward impact force, causing the foam scum to overflow from the outlet of the scum discharge pipe. When the wave-pushing plate moves away from the scum discharge pipe, the water surface in the scum discharge pipe retreats smoothly until the wave-pushing plate moves towards the scum discharge pipe again. By continuously performing the above operations, fluctuations are generated at a certain frequency interval at the upper end opening of the scum discharge pipe, corresponding to multiple scrapers, to achieve continuous removal of the foam scum.

[0073] In a specific embodiment, the wave-pushing plate 14 is in an arc structure, which can increase the contact area with the sewage, making the generated driving force more concentrated and stable.

[0074] In a specific embodiment, a medicine spraying pipe 15 is arranged above the upper end outlet of the scum discharge pipe 6. The medicine spraying pipe 15 can spray the adsorbed medicine powder into the opening of the moving plate 11. The adsorbed medicine powder is magnesium silicate aluminate-coated poly(lactic-co-glycolic acid) microspheres, which can be used to adsorb foam scum and grease to form a gel-like structure.

[0075] Substances such as foam and grease existing on the sewage surface are all substances with strong adhesiveness. Therefore, there will still be a certain amount of grease and foam substances remaining on the scraper. Thus, in the present invention, an adsorption powder of magnesium aluminum silicate-coated poly(lactic-co-glycolic acid) microspheres is sprayed on the scraper. The outer layer of magnesium aluminum silicate has a very large specific surface area and a porous structure, and can adsorb oily substances multiple times its own weight. Therefore, after the foam grease is scraped onto the scraper, magnesium aluminum silicate can quickly adsorb the grease and foam to form a continuously thickening gel-like substance. The gel substance after adsorbing the grease and foam has good fluidity and can easily slide down from the inner wall of the scraper and flow into the discharge tank. Poly(lactic-co-glycolic acid) is a low-molecular-weight degradable material with a fast degradation rate and no pollution to the environment, and also solves the problem of defoaming of subsequent foam.

[0076] Among them, the preparation method of the magnesium aluminum silicate-coated poly(lactic-co-glycolic acid) microspheres is as follows: Mix and stir tetraethyl orthosilicate, hydrochloric acid and water to form a gel, dropwise add solutions of aluminum sulfate and magnesium sulfate, stir and mix, then dropwise add ammonia water to obtain a magnesium aluminum silicate sol; then add the poly(lactic-co-glycolic acid) microsphere powder into the magnesium aluminum silicate sol, stir and mix, age, wash with clear water, calcine, and finally ball mill to obtain a powdery material.

[0077] In a specific embodiment, a buffer interface pipe 16 is provided at the upper opening of the scum discharge pipe 6, and the buffer interface pipe 16 is perpendicular to the outer side wall of the pretreatment tank 1. By providing the buffer interface pipe to extend the length and angle of the upper opening of the scum discharge pipe, it is more conducive to the coordination and connection between the discharge of foam scum and the scraping of the scraper.

[0078] In a specific embodiment, the buffer interface pipe is arranged to incline downward, forming a structure similar to an inverted V shape with the scum discharge pipe. The inclination angle of the upper plate of the buffer interface pipe is greater than that of the lower plate, and the lower plate of the buffer interface pipe is hinged to the side wall of the tank at the outlet of the scum discharge pipe. The lower plate of the buffer interface pipe can contact the scraper and rotate upward under the drive of the scraper, and can freely fall back to the original position after separating from the scraper.

[0079] The buffer interface pipe of the present invention is arranged to slope downwards. Firstly, it can extend the movement path of the overflowing foam through the slope, and at the same time, after the foam waste residue moves through the inclined buffer interface pipe, it can directly "fall" into the scraper; the structure of the buffer interface pipe with a larger upper part and a smaller lower part can buffer the impact force of the overflowing foam, enabling it to fall onto the scraper concentrated in a smaller area; finally, the present invention sets the lower plate of the buffer interface pipe as a hinged structure. When the scraper rotates upwards to the lower plate, the foam waste residue falls from the buffer interface pipe onto the scraper, and the contact between the scraper and the lower plate drives it to rotate upwards (it can also move to contact the end of the upper plate to close the buffer interface pipe), so as to apply a reverse driving force to the foam scum that is about to overflow the lower plate and make it return to the scum discharge pipe. As the scraper continues to rotate and disengages from the lower plate, the lower plate falls back to its original position, and the floating scum foam of the next fluctuation overflows into the buffer interface pipe and falls onto the next scraper.

[0080] In a second aspect, the present invention provides a method for treating sewage surface foam scum, which is characterized by including the following steps:

[0081] 1 Continuously introduce sewage into the sewage area until the water surface is flush with the upper end opening of the scum discharge pipe. Control the water inlet speed and water outlet speed of the sewage area to keep the water surface height of the sewage area. The sewage enters the filtration area through the filter plate structure, and the surface foam scum and grease of the sewage float on the water surface of the sewage area;

[0082] 2 Start the driving drum of the foam scum discharging device, and at the same time start the wave-pushing shaft. During the rotation of the wave-pushing plate, it pushes the lower sewage towards the direction of the scum discharge pipe, generating fluctuations in the water surface inside the scum discharge pipe, and the surface foam scum and grease overflow towards the outlet of the scum discharge pipe. The scraper rotating to the outlet of the scum discharge pipe takes away the overflowing foam scum and grease;

[0083] 3 The foam scum and grease enter the end opening of the scraper, and the scraper continues to move upwards. The foam scum and grease in the scraper flow into the discharge trough along the internal hollow structure and are discharged and collected through the discharge trough;

[0084] 4 The scraper moves downwards into the clear water tank to clean the residual waste residue on the surface, and the scraper continues to move upwards, repeating the above steps to discharge the foam scum.

[0085] The above-mentioned specific implementation manners have further elaborated on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above-mentioned are only the specific implementation manners of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A sewage surface foam scum treatment device, characterized in that: It includes a pretreatment tank (1) and an oxidation treatment tank (2); The pretreatment tank (1) comprises a sewage area (3) and a filter area (4) separated by a partition (17); a water outlet (5) is provided on the partition (17); a scum discharge pipe (6) inclined upward is provided at the water outlet (5); the scum discharge pipe (6) is located in the sewage area (3) and the upper end thereof passes through the sewage area (3) and is connected to the outside; the bottom of the scum discharge pipe (6) is a filter plate structure; water in the sewage area (3) is filtered by the filter plate structure and then enters the filter area (4); The filtration area (4) is connected to the oxidation treatment tank (2); A foam scum discharge device is provided at the outlet of the upper end of the scum discharge pipe (6), and the foam scum discharge device comprises a driving drum (7) arranged parallel to the outlet of the scum discharge pipe (6); a plurality of scrapers (8) are arranged in sequence along the circumferential direction on the outer surface of the driving drum (7); the ends of the scrapers (8) are in an L-hook-shaped structure; a discharge groove (9) is provided on the outer wall of the driving drum (7) beside the scrapers (8); the bottom surface of the discharge groove (9) is inclined along the axis direction of the driving drum (7); the driving drum (7) can rotate around its own axis to drive the scrapers (8) to move to the outlet of the scum discharge pipe (6) to remove the foam scum.

2. A sewage surface foam scum treatment device according to claim 1, characterized in that: The scraper (8) is of a hollow structure, comprising a fixed plate (10) and a movable plate (11); the fixed plate (10) is vertically mounted directly above the discharge groove (9); one end of the movable plate (11) is movably sleeved on the fixed plate (10); the movable plate (11) can be retracted into or extended from the fixed plate (10) along the radial direction of the driving drum (7) under the action of its own weight; the other end of the movable plate (11) is of an L-hook structure, and the end opening is connected to the discharge groove (9).

3. The sewage surface foam scum treatment device according to claim 1, characterized in that: The water outlet (5) is in a horizontal long strip structure, the internal height dimension of the scum discharge pipe (6) gradually decreases from the lower end to the upper end, and the inclination angle of the bottom plate of the scum discharge pipe (6) is greater than the inclination angle of the top plate.

4. A sewage surface foam scum treatment device according to claim 1, characterized in that: A cleaning pool (12) is provided below the driving drum (7) beside the upper outlet of the scum discharge pipe (6), and the cleaning pool (12) is filled with cleaning water.

5. The sewage surface foam scum treatment device according to claim 2, characterized in that: The opening surface of the L-hook-shaped structure at the end of the movable plate (11) is an inclined surface, so that the end has a conical structure.

6. The sewage surface foam scum treatment device according to claim 1, characterized in that: In the sewage area (3), a wave-pushing shaft (13) is provided in the extension direction of the lower end of the scum discharge pipe (6), the wave-pushing shaft (13) being capable of rotating around its own axis, and a wave-pushing plate (14) is vertically connected to the wave-pushing shaft (13).

7. A sewage surface foam scum treatment device according to claim 6, characterized in that: The wave pushing plate (14) has an arc-shaped structure.

8. The sewage surface foam scum treatment device according to claim 2, characterized in that: A spraying pipe (15) is arranged above the upper outlet of the scum discharge pipe (6), and the spraying pipe (15) is capable of spraying adsorption powder into the opening of the movable plate (11). The adsorption powder is polylactic acid-glycolic acid copolymer microspheres coated with magnesium aluminum silicate, and can be used to adsorb foam scum and grease to form a gel-like structure.

9. The sewage surface foam scum treatment device according to claim 2, characterized in that: A buffer interface pipe (16) is provided at the upper opening of the scum discharge pipe (6), and the buffer interface pipe (16) is perpendicular to the outer side wall of the pretreatment tank (1).

10. A sewage treatment method based on the foam scum treatment device according to any one of claims 1 to 9, characterized in that: The steps include: (1) Continuously introduce sewage into the sewage area until the water surface is flush with the upper opening of the scum discharge pipe, control the water inlet and outlet speeds of the sewage area, keep the water surface height of the sewage area constant, and allow the sewage to enter the filter area through the filter plate structure, with the foam scum and grease on the surface of the sewage floating on the surface of the sewage area; (2) Start the driving drum of the foam scum discharge device and start the wave-pushing shaft at the same time. During the rotation of the wave-pushing plate, the sewage at the bottom is pushed to move toward the scum discharge pipe, causing fluctuations on the water surface in the scum discharge pipe. The foam scum and grease on the surface overflow to the outlet of the scum discharge pipe. The scraper rotating to the outlet of the scum discharge pipe takes away the overflowed foam scum and grease; (3) The foam scum and grease enter the end opening of the scraper, and the scraper continues to move upward. The foam scum and grease in the scraper flow into the discharge groove along the internal hollow structure and are discharged and collected through the discharge groove; (4) The scraper moves downward into the clean water pool to clean the residual waste residue on the surface. The scraper continues to move upward and repeats the above steps to discharge the foam scum.

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