A reaction system that facilitates the rapid formation of aerobic granular sludge

Abstract

This utility model discloses a reaction system that facilitates the rapid formation of aerobic granular sludge, including a bioreactor body (1). The bioreactor body (1) is cylindrical, with a conical anoxic denitrification zone (4) integrated at the bottom. An aeration unit is located near the anoxic denitrification zone (4) at the lower part of the cylindrical body. A funnel-shaped hydrocyclone (9) is located at the upper part of the cylindrical body. An inlet pipe (2) is vertically inserted in the middle of the hydrocyclone (9). A water collection tank (13) is located near the upper end of the bioreactor body (1). This utility model has a high volumetric loading rate of 5-10 kg / m3·d, so the bioreactor volume is small, about 1 / 10 of that of the activated sludge process. The dissolved oxygen is low, controlled at 0.7-1.5 mg / L, saving power consumption and reducing carbon source consumption. There is less residual sludge and less biogas, resulting in lower operating costs. The effluent quality is good, reaching Class A.

Description

Technical Field

[0001] This utility model relates to a reaction system that facilitates the rapid formation of aerobic granular sludge. Background Technology

[0002] Currently, conventional activated sludge and biofilm processes are the most common wastewater treatment technologies in my country. However, for wastewater with significant quality fluctuations, especially industrial wastewater, the activated sludge process suffers from poor shock resistance, unstable nitrogen and phosphorus removal, and difficulty consistently meeting discharge standards. The loose microbial structure of activated sludge results in poor settling (settling velocity 0.5–1.5 m / h), making it prone to sludge bulking. Immobilized biofilm processes require carriers, leading to high costs and significant losses. Furthermore, for industrial wastewater, biofilm formation is unstable, and after a period of operation, the packing material is prone to clogging, affecting effluent quality during biofilm detachment. Granular sludge processes, a high-concentration activated sludge method, offer higher cost-effectiveness, lower operating costs, less residual sludge, less biogas, and less secondary pollution compared to conventional chemical sludge processes.

[0003] Currently, the application of aerobic granular sludge processes in practical engineering is mainly based on the sequencing batch reactor (SBR) process, with continuous flow processes being rare. For example, the SBR paper 202323666707.X discloses a novel SBR aerobic sludge bed reactor, including a reactor body. The reactor body comprises a reaction tank and a sedimentation tank arranged from bottom to top, separated by an inclined plate assembly. The reaction tank is equipped with a submersible agitator and a liftable nano-aeration device, while the sedimentation tank is equipped with a two-phase separation device and a triangular weir-type effluent channel assembly from bottom to top. However, the SBR process suffers from low tank volume utilization, complex operation and control, and a high failure rate of the proprietary decanter, directly affecting effluent quality. Utility Model Content

[0004] The main objective of this invention is to provide a reaction system that facilitates the rapid formation of aerobic granular sludge.

[0005] The technical solution adopted by this utility model to solve its technical problem is:

[0006] A reaction system that facilitates the rapid formation of aerobic granular sludge includes a bioreactor body (1), wherein the bioreactor body (1) is cylindrical and has a cone-shaped anoxic denitrification zone (4) integrated at the bottom; and an aeration unit is provided at the lower part of the cylindrical body near the anoxic denitrification zone (4).

[0007] The upper part of the cylindrical part is provided with a funnel-shaped hydrocyclone (9). The upper middle part of the hydrocyclone (9) is provided with slits spaced along the circumferential direction, and a guide plate (10) is provided next to each slit. An acute angle A is formed between the guide plate (10) and the inner wall of the hydrocyclone (9), and all the slits are located at the acute angle A. All the guide plates (10) are inclined in the same direction so that the water coming out of each slit forms a vortex.

[0008] A water inlet pipe (2) is vertically inserted in the middle of the hydrocyclone (9). A gap is left between the outer wall of the water inlet pipe (2) and the inner wall of the lower end of the hydrocyclone (9) as a settling port (12). The lower end of the water inlet pipe (2) branches into multiple water distribution branches (3), which are distributed at intervals along the circumferential direction. Each water distribution branch first approaches the inner wall of the anoxic denitrification zone (4) perpendicular to the inner wall of the anoxic denitrification zone (4) from the branch point, and then turns towards the circumferential direction of the inner wall of the anoxic denitrification zone (4) to form a turning part (3-1). The turning direction of each water distribution branch (3) is the same.

[0009] The bioreactor body (1) is provided with a water collection tank (13) near the upper end. The water in the water collection tank (13) is discharged from the bioreactor body (1) through the water outlet pipe (14). A portion of the water in the water collection tank (13) is returned to the water inlet pipe (2) inside the bioreactor body (1) through the nitrification liquid return pipe (15).

[0010] Furthermore, the aeration unit includes an aeration pipe (6) and an aeration disc (7) spaced apart on the aeration pipe (6).

[0011] Furthermore, the acute angle A is between 20 and 60 degrees. Furthermore, the acute angle A is between 25 and 50 degrees.

[0012] Furthermore, the length directions of the slit and the guide plate (10) are both along the hydrocyclone wall from the outer edge to the center.

[0013] Furthermore, the angle of the water distribution branch pipe is the tangential direction of the anoxic denitrification zone (4).

[0014] Furthermore, a reflux pump (16) is provided on the nitration reflux pipe (15).

[0015] Compared with the prior art, this technical solution has the following advantages:

[0016] System process characteristics:

[0017] 1. High volumetric loading rate, 5-10 kg / m3·d, therefore the bioreactor volume is small, about 1 / 10 of that of the activated sludge process;

[0018] 2. Low dissolved oxygen, controlled at 0.7-1.5 mg / L, saves energy consumption and reduces carbon source consumption;

[0019] 3. Less residual sludge, less biogas, and lower operating costs;

[0020] 4. The effluent water quality is good, reaching Class A. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Figure 1 This is one of the front schematic diagrams of the reaction system of this utility model that facilitates the rapid formation of aerobic granular sludge.

[0023] Figure 2 This is a top view of the water distribution pipe.

[0024] Figure 3 This is a top view of a hydrocyclone.

[0025] In the picture:

[0026] 1-Biotherm body; 2-Inlet pipe; 3-Water distribution branch pipe; 4-Anoxic denitrification zone; 5-Blower; 6-Aeration pipe; 7-Aeration disc; 8-Aerobic zone; 9-Hydrocyclone; 10-Swirl guide plate; 11-Separation zone; 12-Settling port; 13-Water collection tank; 14-Outlet pipe; 15-Nitrified liquid return pipe; 16-Nitrified liquid return pump; 17-Sludge discharge valve; 18-Sludge discharge pipe. Detailed Implementation

[0027] Please refer to Figures 1 to 3 A reaction system that facilitates the rapid formation of aerobic granular sludge includes a biological reactor body 1, which is cylindrical and has a conical anoxic denitrification zone 4 integrally formed at the bottom. A sludge discharge pipe 18 is provided at the bottom of the zone, and a sludge discharge valve 17 is provided on the sludge discharge pipe 18.

[0028] Aeration pipes 6 are laterally arranged at the lower part of the cylindrical section near the anoxic denitrification zone 4. Multiple aeration discs 7 are connected to the aeration pipes 6. The aeration pipes 6 may have multiple branches and can be straight, cross-shaped, annular, mesh-like, etc. Aeration discs 7 are spaced apart on the aeration pipes 6.

[0029] A funnel-shaped hydrocyclone 9 is provided at the upper part of the cylindrical structure. The upper end of the hydrocyclone 9 can be fixed to the inner wall of the bioreactor body 1 by several supports (not shown in the figure). The upper middle part of the hydrocyclone 9 is provided with slits (not shown in the figure) spaced along the circumference, and a guide plate 10 is provided next to each slit. The length direction of the slits and the guide plate 10 are both along the hydrocyclone wall from the outer edge to the center. A separation zone 11 is formed inside and above the hydrocyclone 9.

[0030] An acute angle A is formed between the guide plate 10 and the inner wall of the hydrocyclone 9, with the angle A ranging from 20 to 50 degrees. In this embodiment, it is 30 degrees. All slits are located at acute angle A. All guide plates are tilted in the same direction, causing the water exiting each slit to form a vortex. In this embodiment, the tilting direction is counterclockwise. Figure 3 As indicated by the arrow, the resulting vortex is in a counter-clockwise direction.

[0031] A water inlet pipe 2 is vertically inserted into the center (center) of the hydrocyclone 9. A gap is left between the outer wall of the water inlet pipe 2 and the lower inner wall of the hydrocyclone 9 as a settling port 12. The upper end of the water inlet pipe 2 extends horizontally through the wall of the bioreactor body 1; the lower end of the water inlet pipe 2 branches into four water distribution branches 3, which are distributed at 90-degree intervals along the circumference. Each water distribution branch first approaches the inner wall of the anoxic denitrification zone 4 perpendicularly from the branch point, and then turns towards the circumference of the inner wall of the anoxic denitrification zone 4 to form a bend 3-1, as shown below. Figure 2 As shown. Each water distribution branch pipe 3 bends in the same direction, which in this embodiment is clockwise. This creates a clockwise swirling flow in the anoxic denitrification zone 4. The bend angle is preferably tangential to the anoxic denitrification zone 4.

[0032] The bioreactor body 1 has a water collection tank 13 near its upper end. Water from the water collection tank 13 is discharged from the bioreactor body 1 through a water outlet pipe 14. A portion of the water from the water collection tank 13 returns to the bioreactor body 1 through a nitrification liquid return pipe 15. Specifically, the nitrification liquid return pipe 15 is connected to the lower middle part of the inlet pipe 2. A return pump 16 is installed on the nitrification liquid return pipe 15.

[0033] The working principle of this utility model is as follows:

[0034] Wastewater and returned nitrified liquor enter the anoxic denitrification zone 4 together through inlet pipe 2 and nitrified liquor return pipe 15, respectively, tangentially from the distribution branch pipe 3, for denitrification and phosphorus uptake by polyphosphate-accumulating bacteria. The tangential inlet creates a swirling flow, forming a diffusion streamline flow field in the conical anoxic denitrification zone 4, ensuring thorough mixing and mass transfer of water, solids, and gas, resulting in high biochemical efficiency and increased extracellular enzyme polymers (EPCs) and filamentous bacteria, laying the foundation for granular sludge formation. Simultaneously, polyphosphate-accumulating bacteria release phosphorus and absorb short-chain fatty acids (VFAs) under anaerobic conditions in the denitrification zone.

[0035] The mixed liquor continues to flow vertically upwards into the aerobic zone (above aeration pipes 6 and aeration discs 7), where nitrification and phosphorus uptake by polyphosphate-accumulating bacteria occur. It then flows into the narrow slits of the hydrocyclone 9, where the guide plates 10 create a swirling flow, generating centrifugal force to screen large sludge particles. These large sludge particles slide down the sidewall of the hydrocyclone 9 and settle from the settling port 12 into the biological treatment zone (i.e., the aerobic zone). The supernatant flows upwards along the inverted conical center of the hydrocyclone 9 into the collection tank 13 and flows out of the bioreactor through the outlet pipe 14. Simultaneously, part of the supernatant is returned to the anoxic denitrification zone 4 via the nitrification return pipe 15. Phosphorus-rich sludge is periodically discharged from the sludge discharge pipe 18 at the bottom of the bioreactor.

[0036] The above description is only a preferred embodiment of the present utility model, and therefore cannot be used to limit the scope of the present utility model. All equivalent changes and modifications made in accordance with the scope of the present utility model patent and the contents of the specification should still fall within the scope of the present utility model.

Claims

1. A reaction system that facilitates the rapid formation of aerobic granular sludge, characterized in that: Includes a bioreactor body (1), which is cylindrical and has a cone-shaped anoxic denitrification zone (4) integrated at the bottom; and an aeration unit is provided at the lower part of the cylindrical body near the anoxic denitrification zone (4). The upper part of the cylindrical part is provided with a funnel-shaped hydrocyclone (9). The upper middle part of the hydrocyclone (9) is provided with slits spaced along the circumferential direction, and a guide plate (10) is provided next to each slit. An acute angle A is formed between the guide plate (10) and the inner wall of the hydrocyclone (9), and all the slits are located at the acute angle A. All the guide plates (10) are inclined in the same direction so that the water coming out of each slit forms a vortex. A water inlet pipe (2) is vertically inserted in the middle of the hydrocyclone (9). A gap is left between the outer wall of the water inlet pipe (2) and the inner wall of the lower end of the hydrocyclone (9) as a settling port (12). The lower end of the water inlet pipe (2) branches into multiple water distribution branches (3), which are distributed at intervals along the circumferential direction. Each water distribution branch first approaches the inner wall of the anoxic denitrification zone (4) perpendicular to the inner wall of the anoxic denitrification zone (4) from the branch point, and then turns towards the circumferential direction of the inner wall of the anoxic denitrification zone (4) to form a turning part (3-1). The turning direction of each water distribution branch (3) is the same. The bioreactor body (1) is provided with a water collection tank (13) near the upper end. The water in the water collection tank (13) is discharged from the bioreactor body (1) through the water outlet pipe (14). A portion of the water in the water collection tank (13) is returned to the water inlet pipe (2) inside the bioreactor body (1) through the nitrification liquid return pipe (15).

2. The reaction system according to claim 1, characterized in that: The aeration unit includes an aeration pipe (6) and an aeration disc (7) spaced apart on the aeration pipe (6).

3. The reaction system according to claim 1, characterized in that: The acute angle A is between 20 and 60 degrees.

4. The reaction system according to claim 3, characterized in that: The acute angle A is between 25 and 50 degrees.

5. The reaction system according to claim 1, characterized in that: The length directions of the slit and the guide plate (10) are both along the wall of the hydrocyclone from the outer edge to the center.

6. The reaction system according to claim 1, characterized in that: The angle of the water distribution branch pipe is the tangent direction of the anoxic denitrification zone (4).

7. The reaction system according to claim 1, characterized in that: A reflux pump (16) is provided on the nitration liquid reflux pipe (15).

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