Impeller of sludge stirrer for sewage treatment

Abstract

The utility model discloses a sludge stirrer impeller for sewage treatment. The sludge stirrer impeller comprises a sludge stirrer impeller body, the water inlet end of the sludge stirrer impeller body is in a first arc shape; the outer lead angle of the sludge stirrer impeller body is arc-shaped; and the water outlet end of the sludge stirrer impeller body is in a second arc shape. The operation performance and the operation efficiency of the stirrer are improved, the requirements of a sewage treatment process flow are met, the water quality is stabilized, the operation efficiency is improved, and powerful support is provided.

Description

Technical Field

[0001] The utility model relates to a sludge agitator in sewage treatment technology, and more specifically to an impeller of a sludge agitator for sewage treatment. Background Art

[0002] A forced-propulsion agitator is arranged in the biochemical pool of the sewage treatment plant to force the sludge to stir and prevent it from settling. The existing agitator is mainly composed of a motor, an impeller, and a mounting system to achieve the solid-liquid two-phase flow and the homogenization and flow of solid and liquid in the biochemical process. The impeller is precision cast or stamped from stainless steel and other materials, and the blades are swept back, which is highly efficient and has an anti-winding function.

[0003] Now a large number of agitator product designs focus on the agitator's axial thrust, number of blades, impeller diameter, efficiency and other aspects, and are basically universal products.

[0004] Existing sewage treatment plants all have fixed parameters, fixed speed and frequency, and fixed motors when they leave the factory.

[0005] Therefore, the conventional factory installation practice, although it can meet the basic requirement of sludge not settling, does not actively pay attention to the needs of sewage plant operating conditions to maintain the limitations of sludge flocs.

[0006] The existing agitators for sludge mixing have the disadvantages of excessive mixing and easy generation of cavitation cavities, etc. The disadvantages are more obvious in deep-type biological pools. The layout of the double-layer agitator will cause the activated sludge flocs to be crushed, the treatment system will be broken up, the energy consumption is high, and the properties of the activated sludge are not good. Utility Model Content

[0007] In view of the defects existing in the prior art, the purpose of the utility model is to provide a sludge agitator impeller for sewage treatment, so as to improve the operating performance and efficiency of the agitator, meet the needs of the sewage treatment process, achieve stable water quality, improve operating efficiency, and provide strong support.

[0008] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0009] A sludge agitator impeller for sewage treatment, comprising a sludge agitator impeller body;

[0010] The water inlet end of the impeller body of the sludge agitator is configured as a first arc shape;

[0011] The outer guide angle of the impeller body of the sludge agitator is set to be an arc shape;

[0012] The water outlet end of the impeller body of the sludge agitator is arranged in a second arc shape.

[0013] Preferably, the longitudinal cross-section thickness of the water entry end is d1;

[0014] The length of the first arc is L1=5d1.

[0015] Preferably, the first arc is an elliptical arc;

[0016] The center distance of the elliptical arc is L1, and the radius is L1+d1.

[0017] Preferably, the arc-shaped variable diameter is 10d1.

[0018] Preferably, the longitudinal cross-sectional thickness of the water outlet end is d2;

[0019] The length of the second arc is L2=5d2.

[0020] Preferably, the second arc is an elliptical arc;

[0021] The center distance of the elliptical arc is L2, and the radius is L2+d2.

[0022] Preferably, the longitudinal cross-sectional thickness d1 of the water inlet end is equal to the longitudinal cross-sectional thickness d2 of the water outlet end;

[0023] The length L1 of the first arc is equal to the length L2 of the second arc.

[0024] The utility model provides a sludge agitator impeller for sewage treatment, which has the following beneficial effects:

[0025] 1) The biological pool of sewage treatment is the main process section for energy consumption. In the daily operation process, the agitator is continuously running, and the degree of sludge crushing is uncontrollable. Through the improved impeller of the utility model, the agitator can effectively reduce the degree of sludge crushing, operate stably, and improve the operating efficiency.

[0026] 2) The vacuum chamber of the impeller is reduced, the hydraulic efficiency is improved, energy saving and consumption reduction are achieved, and the green benefits are more obvious. Under the background of dual carbon, it not only improves the operation control capability, but also improves the operation stability of the sewage plant.

[0027] 3) The utility model solves the problem of in-situ optimization and upgrading of the agitator, and there is no need to purchase a new agitator, so the utility model can be promoted. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the impeller of the sludge agitator for sewage treatment of the utility model;

[0029] Figure 2 It is a schematic diagram of the longitudinal section of the water inlet end of the impeller of the sludge agitator for sewage treatment of the utility model;

[0030] Figure 3 It is a schematic diagram of the simulation effect of the vacuum cavity of the impeller of the sludge agitator for sewage treatment of the utility model. DETAILED DESCRIPTION

[0031] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0032] Combination Figure 1 As shown, according to the sludge characteristics of the sewage treatment plant, the utility model provides a sludge agitator impeller for sewage treatment, including a sludge agitator impeller body 100, to meet the working scene requirements of mud propulsion.

[0033] The water inlet end 1 of the sludge agitator impeller body 100 is configured as a first arc shape, thereby reducing the impact surface and increasing the contact surface, thereby reducing the degree of crushing of the activated sludge flocs.

[0034] The outer guide angle 2 of the sludge agitator impeller body 100 is set to be an arc shape, and the curvature is improved to reduce fluid impact, thereby reducing the impact force and reducing the generation of cavitation cavities, thereby protecting the impeller.

[0035] The water outlet end 3 of the sludge agitator impeller body 100 is arranged in a second arc shape to form a slowing slope, thereby slowing down the vacuum caused by the fluid impact and improving the hydraulic efficiency of the impeller.

[0036] Combination Figure 2 The longitudinal section of the water inlet end 1 of the impeller body 100 of the sludge agitator shown in the figure, d1 is the thickness of a single blade, which is also the end face shape of the original blade, and forms a 90-degree impact with the working medium. According to the hydraulic characteristics of the end face of the water inlet end 1 of the impeller body 100 of the sludge agitator, within a length range of 5 times of d1 (i.e., L1 length), the water inlet end 1 is set to a first arc shape, and the first arc shape is set to an elliptical arc shape (such as Figure 2 The larger side is located at the water entry end 1 (i.e. the original position of d1). The distance between the centers of the elliptical arc is L1, and the radius is L1+d1.

[0037] The outer lead angle of the existing impeller is generally an obtuse angle. The working conditions during sewage treatment are different from those of ordinary agitators. The viscosity and weight of the working fluid are relatively large. Therefore, under the working conditions of sewage treatment, the hydraulic model formed by the outer lead angle will form additional stress and cavity, and form cavitation after long-term operation.

[0038] The outer chamfer 2 of the sludge agitator impeller body 100 is set to an arc shape. With the outer chamfer 2 as the center and a radius 10 times that of d1, the center of the circle is mirrored and the outer chamfer 2 is processed into an outer arc with a radius 10 times that of d1.

[0039] The water outlet end 3 of the sludge agitator impeller body 100 is similar to the water inlet end 1 of the sludge agitator impeller body 100, which can be referred to Figure 2 As shown, according to the hydraulic characteristics of the end face of the water outlet end 3 of the sludge agitator impeller body 100, within a length range of 5 times d2 (i.e., length L2), the water outlet end 3 is set to a second arc, and the second arc is set to an elliptical arc, with the larger side located at the water outlet end 3 (i.e., the original d2 position). The center distance of the elliptical arc is L2, and the radius is L2+d2.

[0040] In summary, the impeller of the sludge agitator for sewage treatment of the utility model is improved on the basis of the conventional submersible agitator by comparing with the demand characteristics of the sewage treatment plant's natural retort tank. The method combining hydraulic model design and actual operation experience is adopted to optimize and improve the three aspects of the crushing characteristics of the flocs, cavitation characteristics and sludge flow characteristics.

[0041] The utility model alleviates the problem of high degree of crushing of activated sludge flocs in underground sewage treatment plants: the degree of crushing of activated sludge flocs in the existing sewage treatment reactors is high, which has a significant impact on subsequent processes. This is mainly because the crushing of the flocs is directly related to the impact force of the water inlet end of the blades. The water inlet end face of the original impeller is at a right angle of 90 degrees to the blades, which brings a large impact force to the sludge, causing the sludge flocs to directly bear high-speed impact when contacting the end face and be crushed by the impeller. The utility model changes the hydraulic model of the blades, reduces the impact surface at the water inlet end of the water flow, and increases the contact surface at the same time, changes the water inlet end of the impeller into an arc shape, reduces the impact force generated when entering the water, and achieves the effect of reducing the degree of crushing of the activated sludge flocs. By controlling the quality of the sludge in the reactor relative to the source, it is easy to adapt to the treatment needs of subsequent processes, while having the characteristics of practicality and simplified process.

[0042] The utility model alleviates the phenomenon of cavitation in the agitator: there are obvious cavitation marks on the lead angle of the outer edge of the existing impeller close to the water entry surface, and almost every lead angle has similar cavitation holes with similar depths. The main reason is that the sludge in the reaction tank is heavy, which causes cavitation holes caused by local vacuum. Therefore, according to the results of hydraulic model simulation, the utility model makes the outer lead angle of the impeller into an arc shape, and improves the curvature to reduce the vacuum caused by the high-speed flow of the fluid. By reducing the vacuum cavity and reducing the generation of cavitation holes, the impeller is protected.

[0043] The utility model improves the hydraulic efficiency of the impeller: due to the high concentration of sludge and certain viscosity, which is different from the physical properties of conventional water bodies, the impeller design of general agitators is difficult to cover the special working conditions of sludge mixing. According to the effect of hydraulic model simulation, combined with the position of the impeller cavitation hole and the simulated sludge flow state, the shape of the water outlet end of the original impeller is easy to produce a vacuum cavity (such as Figure 3 The utility model adopts a high-precision hydraulic model design to deeply optimize the hydraulic model of the sludge stirring impeller, processes the water outlet end of the impeller, creates a slope at the water outlet end, alleviates the flow steps of the sludge at the water outlet end, and reduces the structural conditions for forming a vacuum cavity at the water outlet end, thereby achieving the effect of improving the hydraulic efficiency of the impeller.

[0044] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A sludge agitator impeller for sewage treatment, characterized in that: It includes a sludge agitator impeller body; The water inlet end of the impeller body of the sludge agitator is configured as a first arc shape, and the first arc shape is configured as an elliptical arc shape. The longitudinal section thickness of the water inlet end is d1, where d1 is the thickness of a single blade; The outer chamfer of the impeller body of the sludge agitator is set to be an arc shape, with the outer chamfer as the center of the circle and a radius 10 times that of d1, and the center of the circle is mirrored, with the radius 10 times that of d1, and the outer chamfer is processed into an outer arc; The water outlet end of the impeller body of the sludge agitator is arranged in a second arc shape, which is similar to the water inlet end of the impeller body of the sludge agitator.

2. The impeller of the sludge agitator for sewage treatment according to claim 1, characterized in that: The longitudinal section thickness of the water inlet end is d1; The length of the first arc is L1=5d1.

3. The impeller of the sludge agitator for sewage treatment according to claim 2, characterized in that: The first arc is an elliptical arc; The center distance of the elliptical arc is L1, and the radius is L1+d1.

4. The impeller of the sludge agitator for sewage treatment according to claim 2, characterized in that: The diameter change of the circular arc is 10d1.

5. The impeller of the sludge agitator for sewage treatment according to claim 3, characterized in that: The longitudinal cross-sectional thickness of the water outlet is d2; The length of the second arc is L2=5d2.

6. The impeller of the sludge agitator for sewage treatment according to claim 5, characterized in that: The second arc is an elliptical arc; The center distance of the elliptical arc is L2, and the radius is L2+d2.

7. The impeller of the sludge agitator for sewage treatment according to claim 6, characterized in that: The longitudinal cross-sectional thickness d1 of the water inlet end is equal to the longitudinal cross-sectional thickness d2 of the water outlet end; The length L1 of the first arc is equal to the length L2 of the second arc.

Images