Lateral flow biological floc concentration device and sewage treatment system

Abstract

The utility model provides a lateral flow biological floc concentration device and a sewage treatment system, which comprise a mud scraping assembly and a concentration steady flow assembly, the mud scraping assembly comprises a support and a scraper conveyer arranged on the support; the concentration flow stabilizing assembly is arranged in the cavity of the support and comprises a plurality of water filtering folded plates arranged at intervals, the water filtering folded plates comprise inclined plates and vertical plates, included angles are formed between the inclined plates and the vertical plates, and the inclined plates are located above the vertical plates. According to the lateral flow biological floc concentration device provided by the utility model, due to the unique design of the inclined plate and the vertical plate of the water filtering folded plate in the concentration flow stabilizing assembly, when water flows through the water filtering folded plate, biological floc particles are intercepted by the inclined plate under the gravity settling action and are concentrated and enriched by the vertical plate, so that the biological floc particles are concentrated and enriched; the sludge discharge assembly and other assemblies such as a sludge discharge tank in the concentration device are matched, so that the concentration, backflow and utilization of biological flocs are realized, the treatment efficiency of the biochemical pool is improved, the solid load of the secondary sedimentation tank is synchronously reduced, and the in-situ expansion of the biochemical pool and the secondary sedimentation tank is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of concentration equipment, in particular to a lateral flow biological floc concentration device and a sewage treatment system. Background Art

[0002] The secondary sedimentation tank in the sewage treatment plant needs to use gravity sedimentation for a certain period of time to separate the mud and water and achieve the clarification of the mixed liquor. The higher the concentration of the mixed liquor entering the secondary sedimentation tank, the longer it takes to clarify. When the concentration of the mixed liquor continues to increase or the sedimentation performance deteriorates, the sludge will enter the subsequent treatment structures from the secondary sedimentation tank along with the effluent, affecting the effluent water quality while increasing the operating costs of the subsequent structures. This phenomenon is commonly known as "sludge running". During low-temperature operation in winter, the ability of the biochemical pool to remove pollutants is often maintained by increasing the sludge concentration. However, the increase in sludge concentration and the decrease in microbial metabolic activity will lead to an increase in the viscosity of the activated sludge. The sedimentation ability of the sludge decreases with the increase in viscosity, and the sedimentation effect of the secondary sedimentation tank weakens, which leads to the problem of sludge running. In addition, the expansion of filamentous bacteria will also lead to poor sludge sedimentation performance.

[0003] The high-concentration composite powder carrier biological fluidized bed technology uses micron-sized composite powder carriers with good biological affinity to attach microorganisms, forming a "double mud" system of attached growth and suspended growth. Double mud refers to biological flocs with a larger specific gravity and light activated sludge. This technology increases the sludge concentration of the biochemical pool from 3-4g / L in the conventional activated sludge method to 5-10g / L by adding composite powder carriers. The surface of the attached microbial carrier forms bioflocs, which enhances the sewage treatment efficiency of the biochemical pool and realizes in-situ expansion of the biochemical pool. However, the increase in sludge concentration leads to an increase in the actual operating solid load of the secondary sedimentation tank, which limits the ability of the secondary sedimentation tank to expand in-situ.

[0004] In summary, there is an urgent need for a lateral flow biofloc concentration device and a sewage treatment system to solve the technical problems existing in the related technologies. Utility Model Content

[0005] The main purpose of the utility model is to provide a lateral flow biological floc concentrating device and a sewage treatment system to solve the mud leakage problem existing in the related technology.

[0006] To achieve the above-mentioned purpose, the utility model provides a lateral flow biological floc concentrating device, including a sludge scraping assembly and a concentrating and stabilizing flow assembly, wherein the sludge scraping assembly includes a bracket and a scraper conveyor running around the longitudinal outer peripheral surface of the bracket, and the bracket has a cavity for accommodating the concentrating and stabilizing flow assembly;

[0007] The concentration and stabilizing flow assembly is arranged in the cavity of the bracket, and the concentration and stabilizing flow assembly includes a plurality of water filtering folding plates arranged at intervals along the lateral direction of the bracket, and the water filtering folding plates include an inclined plate and a correspondingly connected vertical plate, and the inclined plate and the vertical plate are arranged at an angle, and the inclined plate is located above the vertical plate; the height w of the orthographic projection of the vertical plate on the vertical plane of the bracket satisfies the formula:

[0008]

[0009] Wherein, H represents the height of the concentrator, L represents the length of the concentrator, μ represents the settling velocity of the biological floc particles, and V represents the average flow velocity of the water.

[0010] Preferably, the angle between the water-facing surface of the inclined plate and the water flow direction is 45-65°; the angle between the water-facing surface of the vertical plate and the water flow direction is 45-65°.

[0011] Preferably, the angle between the plane where the inclined plate is located and the vertical plane of the bracket is 135-155°.

[0012] Preferably, the plane on which the vertical plate is located is parallel to the vertical plane of the bracket.

[0013] Preferably, the water filter folds are distributed at equal intervals in the transverse direction of the bracket, and the spacing distance between adjacent water filter folds is 60-200 mm.

[0014] Preferably, the scraper conveyor comprises a driving member, a transmission mechanism and a scraper blade, the transmission mechanism is arranged on a bracket, and a plurality of scrapers are arranged on the transmission mechanism at intervals.

[0015] Preferably, the transmission mechanism includes a transmission shaft, a chain and a gear, at least two chains are respectively arranged around the longitudinal outer circumference of the bracket through gears, and are arranged parallel to each other, and the transmission shaft is transmission connected to each chain and to the output end of the driving member.

[0016] Preferably, the spacing between adjacent scraper blades is 500-5000 mm, and the width of the scraper blades is 150-200 mm.

[0017] Preferably, the conveying speed of the scraper conveyor is 0.005-0.02 m / s.

[0018] Preferably, the bracket is also provided with a plurality of lifting rings.

[0019] The beneficial effects of the utility model are:

[0020] The utility model provides a lateral flow biological floc concentrating device, which accelerates the sedimentation and concentration of biological flocs in muddy water through a concentrating and stabilizing flow component, that is, through the unique design of the inclined plate and the vertical plate of the water filter folding plate in the concentrating and stabilizing flow component, when the water flows through the water filter folding plate, under the action of gravity sedimentation, the biological floc particles with a large specific gravity are intercepted by the inclined plate and concentrated and enriched by the vertical plate, the settled and enriched biological flocs are collected by the mud discharge component, and in conjunction with other components such as a mud discharge trough and a reflux pump, the concentrated and enriched biological flocs are returned to the biochemical front end in the form of reflux for recycling; the light sludge with low concentration in the upper part enters the secondary sedimentation tank, which effectively reduces the solid load of the secondary sedimentation tank, thereby solving the problems of mud running and limited in-situ expansion existing in the related technology.

[0021] The biological floc concentrating device provided by the utility model is suspended at the end of the aerobic pool of the sewage treatment system through a bracket to construct a concentration area without adding additional land, and the number of installations can be flexibly adjusted according to the pool structure and the demand for treated water volume.

[0022] The utility model also provides a sewage treatment system using the above-mentioned lateral flow biological floc concentrating device, the sewage treatment system includes an anaerobic tank, an anoxic tank, an aerobic tank and a second sedimentation tank connected in sequence; a sludge return pipeline is also arranged between the aerobic tank and the anoxic tank and between the second sedimentation tank and the anaerobic tank, the lateral flow biological floc concentrating device is arranged in the aerobic tank to construct a concentration zone; the biological floc particles are preferably added by a composite powder carrier and cultured in the sewage treatment system. The biological floc particles formed by the above-mentioned sewage treatment system have a large specific gravity and a better sedimentation performance than light activated sludge. The concentrating device designed by the utility model realizes concentration and enrichment in situ at the end of the aerobic tank, and realizes recycling in the biochemical tank through a reflux pump, thereby improving the sedimentation performance of the biochemical system, and thus improving the sewage treatment efficiency of the biochemical tank; the low-concentration light activated sludge on the upper part of the concentrating device enters the second sedimentation tank, which improves the in-situ treatment capacity of the second sedimentation tank, and at the same time, part of the light activated sludge is eliminated from the system after secondary screening, optimizing the microbial community structure in the biochemical tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model 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 utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0024] Figure 1 Schematic diagram of the structure of a lateral flow biofloc concentration device according to one embodiment of the present application (the x-axis represents the horizontal direction; the y-axis represents the longitudinal direction; and the z-axis represents the vertical direction);

[0025] Figure 2 It is a schematic structural diagram of a water filter folding plate in a lateral flow biological floc concentrating device according to an embodiment of the present application;

[0026] Figure 3 It is a schematic diagram of the setting in an aerobic pool according to one embodiment of the present application;

[0027] Figure 4 It is a structural schematic diagram of a sewage treatment system according to one embodiment of the present application.

[0028] Among them, 1- bracket, 2- inclined plate, 3- vertical plate, 4- driving member, 5- scraper plate, 6- transmission shaft, 7- chain, 8- gear, 9- concentration area, 10- mud discharge trough.

[0029] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with the implementation methods and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] It should be noted that all directional indications (such as up, down, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0033] Furthermore, the technical solutions between the various implementation modes of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] Example 1: See Figure 1The utility model provides a lateral flow biological floc concentrating device, including a scraper assembly and a concentrating and stabilizing flow assembly, wherein the scraper assembly includes a bracket 1 and a scraper conveyor running around the longitudinal outer peripheral surface of the bracket 1, and the bracket 1 has a cavity for accommodating the concentrating and stabilizing flow assembly;

[0035] The concentrating and stabilizing flow assembly is arranged in the cavity of the bracket, and the concentrating and stabilizing flow assembly includes a plurality of water filtering folding plates arranged at intervals along the lateral direction of the bracket, see Figure 2 The water filter folding plate includes an inclined plate 2 and a vertical plate 3. The inclined plate 2 and the vertical plate 3 are arranged at an angle, and the inclined plate 2 is located above the vertical plate 3. The height w of the orthographic projection of the vertical plane of the bracket of the vertical plate 3 satisfies the formula:

[0036]

[0037] Wherein, H represents the depth of the concentrator, L represents the length of the concentrator, μ represents the settling velocity of the biofloc particles, and V represents the average flow velocity of the water.

[0038] The utility model provides a lateral flow biological floc concentrating device, which accelerates the sedimentation of biological flocs (such as activated sludge) in muddy water through a concentrating and stabilizing flow component, that is, through the unique design of the inclined plate and the vertical plate of the water filter folding plate in the concentrating and stabilizing flow component, the water flow is intercepted by the inclined plate under the action of gravity sedimentation when flowing through the water filter folding plate, and is concentrated and enriched by the vertical plate, and the settled and enriched biological flocs are collected by the mud discharge component, see Figure 3 , in conjunction with other components in the concentration zone 9 such as the sludge discharge tank 10, the concentrated high-density biological flocs are recycled and utilized to improve the treatment efficiency of the biochemical pool, and the low-concentration light-density activated sludge enters the rear-end secondary sedimentation tank, effectively reducing the solid load of the secondary sedimentation tank, thereby solving the problems of sludge running and limited in-situ expansion in related technologies.

[0039] Furthermore, when designing the water filter folding plate, the utility model author referred to the shallow pool theory, assuming that the length of the concentration device is L, the depth is H, the horizontal flow rate of the inflow is V, and the sedimentation rate of the biological floc particles is μ. Under ideal conditions, L / H ≥ V / μ. The values ​​of L and V generally remain unchanged, and it can be seen that the shallower the pool body, the smaller the suspended particles that can be removed. Therefore, the inclined plate and the vertical plate in the water filter folding plate are set at an angle, so that particles with a slower sedimentation rate can settle to the surface of the inclined plate, be enriched by the vertical plate under the action of the inclined plate, and finally be collected and recycled by the mud discharge assembly.

[0040] Furthermore, the utility model inventors consider that since the smaller biofloc particles are unevenly distributed in the water pool, in order to fully recover them, it is necessary to design the projection height of the inclined plate in the vertical direction. Ideally, the projection height of the inclined plate in the vertical direction should satisfy the formula:

[0041]

[0042] In this embodiment, the height of the concentrator is 3m, the length of the concentrator is 5m, the settling velocity of the biological floc particles is 1.5mm / s, and the average flow velocity of the inflow is 5mm / s. Therefore, the projection height of the inclined plate in the vertical direction is set to 1.5m. Since the angle between the inclined plate and the vertical plate is 60°, the length of the inclined plate is 3m.

[0043] In this embodiment, the angle between the water-facing surface of the inclined plate 2 and the water flow direction is 45-65°; the angle between the water-facing surface of the vertical plate 3 and the water flow direction is 45-65°.

[0044] In the present application, the above angles are all 45°. Through appropriate angle design, it is possible to effectively prevent floating objects in the water flow from being entangled and avoid blockage problems.

[0045] In this embodiment, the angle between the plane where the inclined plate 2 is located and the vertical plane of the bracket is 135-155°.

[0046] In this embodiment, the plane where the vertical plate is located is parallel to the vertical plane of the bracket.

[0047] Specifically, the angle between the plane where the inclined plate is located and the vertical direction is 135-155°, and the plane where the vertical plate is located is parallel to the vertical direction, that is, the angle between the inclined plate and the vertical plate is 135-155°. In this embodiment, the specific value of the angle is 150°. When the water flows through the water filter folding plate, the biological floc particles are intercepted by the inclined plate under the action of gravity sedimentation and concentrated and enriched by the vertical plate.

[0048] It is worth noting that the vertical plates in this application can not only enrich the biological floc particles, but also have the function of stabilizing the water flow. Compared with a single inclined plate setting, the biological flocs will be concentrated on one side of the sedimentation tank and cause the water flow velocity to decrease, and the water flow efficiency of the sedimentation tank will be reduced; the solution of adding vertical plates can stabilize the water flow, while reducing the impact on the water flow velocity, it can also make the biological flocs evenly distributed at the bottom of the sedimentation tank, which is convenient for collection through the sludge discharge component.

[0049] In this embodiment, the water filter folds are distributed at equal intervals in the transverse direction of the bracket, and the spacing distance between adjacent water filter folds is 60-200 mm.

[0050] Since the water filter folds (i.e., the inclined plates and vertical plates) have a certain thickness (10 mm in this embodiment), the water flow will inevitably be affected when passing through the water filter folds, resulting in diversion to both sides of the water filter folds. When the distribution density of the water filter folds is low, although the above diversion has a slight effect on the flow rate, it is beneficial to the precipitation of small particles of biological flocs in the water, so that they can settle to the surface of the inclined plates faster, and the advantages outweigh the disadvantages; and when the distribution density of the water filter folds is high, more diversions are generated, which greatly affects the water flow efficiency of the sedimentation tank, is not conducive to industrial production, and the disadvantages outweigh the advantages. Therefore, in this application, the spacing between adjacent water filter folds is 60-200 mm. In this embodiment, it is 100 mm.

[0051] In this embodiment, the scraper conveyor includes a driving member 4 (a motor in this embodiment), a transmission mechanism and a scraper 5. The transmission mechanism is arranged on a bracket 1, and a plurality of scrapers 5 are arranged on the transmission mechanism at intervals.

[0052] In this embodiment, the transmission mechanism includes a transmission shaft 6, a chain 7 and a gear 8. The two chains 7 are respectively arranged around the longitudinal outer circumference of the bracket (1) through the gear 8, and are arranged parallel to each other. The transmission shaft 6 is transmission connected to each chain 7 and is transmission connected to the output end of the driving member 4.

[0053] In this embodiment, the interval between adjacent scraper blades is 500-5000 mm, and the width of the scraper blades is 150-200 mm.

[0054] In this embodiment, the conveying speed of the scraper conveyor is 0.005-0.02 m / s.

[0055] In this embodiment, the bracket 1 is further provided with a plurality of lifting rings.

[0056] By providing a lifting ring, the lateral flow biological floc concentrating device can be conveniently and quickly lifted to the concentrating area, and can also be taken out from the concentrating area when replacement or cleaning is required.

[0057] For further information, see Figure 4 The lateral flow biological floc concentrating device is applied to a sewage treatment system, wherein the sewage treatment system comprises an anaerobic tank, an anoxic tank, an aerobic tank and a second sedimentation tank which are connected in sequence; a sludge return pipeline is also arranged between the aerobic tank and the anoxic tank and between the second sedimentation tank and the anaerobic tank; the lateral flow biological floc concentrating device is arranged in the aerobic tank to construct a concentration zone; the biological flocs are preferably cultured and formed in the sewage treatment system by adding a composite powder carrier.

[0058] The precipitation data of biological flocs in the water flow by the lateral flow biological floc concentrator in Example 1 at different water flow rates are shown in Table 1:

[0059] Table 1 The precipitation results of biological flocs in water flow by the lateral flow biological floc concentrator of Example 1 at different water flow rates

[0060]

[0061]

[0062] Note: MLSS means the concentration of suspended solids in the mixed liquor; MLVSS means the concentration of volatile suspended solids in the mixed liquor; VSS / SS means the ratio of the concentration of volatile suspended solids to the concentration of suspended solids in the mixed liquor; the control group is the control of the sedimentation effect of bioflocs in the water flow when the lateral flow biofloc concentrator is not installed. The upper part refers to the upper part of the concentrator inclined plate and the lower part of the concentrator vertical plate.

[0063] It can be seen from Table 1 that the lateral flow biological floc concentrating device provided in the present application realizes the concentration and enrichment of biological floc particles by enhancing sedimentation, and the concentration of sludge entering the secondary sedimentation tank is reduced, thereby reducing the solid load of the secondary sedimentation tank, solving the possible sludge leakage problem of the secondary sedimentation tank, and realizing the improvement of the treatment capacity of the secondary sedimentation tank.

[0064] Embodiment 2: The difference from Embodiment 1 is that the angle between the plane where the inclined plate is located and the vertical direction is 55°.

[0065] Embodiment 3: The difference from Embodiment 1 is that the angle between the plane where the inclined plate is located and the vertical direction is 65°.

[0066] Comparative Example 1: The difference from Example 1 is that the projection height of the inclined plate in the vertical direction is 0.5, and since the angle between the inclined plate and the vertical plate is 60°, the length of the inclined plate is 1 m.

[0067] Comparative Example 2: The difference from Example 1 is that no vertical plate is provided.

[0068] Comparative Example 3: The difference from Example 1 is that the angle between the plane where the inclined plate is located and the vertical direction is 40°.

[0069] Comparative Example 4: The difference from Example 1 is that the angle between the plane where the inclined plate is located and the vertical direction is 80°.

[0070] Comparative Example 5: The difference from Example 1 is that the conveying speed of the scraper conveyor is 0.03 m / s.

[0071] Statistics of Examples 1-3 and Comparative Examples 1-5 show that at a water flow rate of 25 m 3 / h, and the residence time in the filter plate area is 5min. The results are shown in Table 2:

[0072] Table 2 The precipitation results of biological flocs in water flow by the lateral flow biological floc concentrator provided in Examples 1-3 and Comparative Examples 1-5 at different water flow rates

[0073]

[0074] The above technical solutions of the present invention are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A lateral flow biofloc concentration device, characterized in that: It comprises a sludge scraping assembly and a concentrating and stabilizing flow assembly, wherein the sludge scraping assembly comprises a bracket (1) and a scraper conveyor running around the longitudinal outer peripheral surface of the bracket (1), and the bracket (1) has a cavity for accommodating the concentrating and stabilizing flow assembly; The concentration and stabilizing flow assembly is arranged in the cavity of the bracket, and comprises a plurality of water filtering folding plates arranged at intervals along the lateral direction of the bracket, wherein the water filtering folding plates comprise an inclined plate (2) and a correspondingly connected vertical plate (3), wherein the inclined plate (2) and the vertical plate (3) are arranged at an angle, and the inclined plate (2) is located above the vertical plate (3); the height w of the orthographic projection of the vertical plate (3) on the vertical plane of the bracket satisfies the formula: Wherein, H represents the height of the concentrator, L represents the length of the concentrator, μ represents the settling velocity of the biological floc particles, and V represents the average flow velocity of the water.

2. The lateral flow biological floc concentrating device according to claim 1, characterized in that: The angle between the water-facing surface of the inclined plate (2) and the direction of the water flow is 45-65°; the angle between the water-facing surface of the vertical plate (3) and the direction of the water flow is 45-65°.

3. The lateral flow biological floc concentrating device according to claim 1, characterized in that: The angle between the plane where the inclined plate (2) is located and the vertical plane of the bracket is 135-155°.

4. The lateral flow biological floc concentrating device according to claim 1, characterized in that: The plane on which the vertical plate (3) is located is parallel to the vertical plane of the bracket.

5. The lateral flow biological floc concentrating device according to claim 1, characterized in that: The water filter folding plates are distributed at equal intervals along the horizontal direction of the bracket, and the spacing distance between adjacent water filter folding plates is 60-200mm.

6. The lateral flow biological floc concentrating device according to claim 1, characterized in that: The scraper conveyor comprises a driving member (4), a transmission mechanism and a scraper (5); the transmission mechanism is arranged on a bracket (1), and a plurality of scrapers (5) are arranged on the transmission mechanism at intervals.

7. The lateral flow biological floc concentrating device according to claim 6, characterized in that: The transmission mechanism comprises a transmission shaft (6), a chain (7) and a gear (8); at least two chains (7) are respectively arranged around the longitudinal outer peripheral surface of the bracket (1) through the gear (8), and are arranged in parallel with each other; the transmission shaft (6) is transmission-connected to each chain (7) and is transmission-connected to the output end of the driving member (4).

8. The lateral flow biological floc concentrating device according to claim 6, characterized in that: The distance between adjacent scraper blades (5) is 500-5000 mm, and the width of the scraper blade (5) is 150-200 mm.

9. The lateral flow biological floc concentrating device according to any one of claims 1 to 8, characterized in that: The conveying speed of the scraper conveyor is 0.005-0.02m / s.

10. A sewage treatment system using the lateral flow biological floc concentrating device according to any one of claims 1 to 9, characterized in that: The sewage treatment system comprises an anaerobic tank, an anoxic tank, an aerobic tank and a second sedimentation tank which are connected in sequence; a sludge return pipeline is also arranged between the aerobic tank and the anoxic tank and between the second sedimentation tank and the anaerobic tank; the lateral flow biological floc concentrating device is arranged in the aerobic tank to construct a concentrating area; the biological flocs are preferably cultured and formed in the sewage treatment system by adding a composite powder carrier.

Images