Low-carbon-source sewage aerobic granular sludge treatment device and use method

Abstract

The invention discloses a low-carbon-source sewage aerobic granular sludge treatment device and a use method, and relates to the technical field of sewage treatment.The device comprises a sludge hydrolysis zone and a reaction zone, the sludge hydrolysis zone and the reaction zone are sequentially communicated, the sludge hydrolysis zone is located below the reaction zone, sludge exists in the sludge hydrolysis zone, and the reaction zone is located below the reaction zone. The water inlet main pipe is used for supplying water into the reaction area, a water inlet pump is arranged on the water inlet main pipe, and when sewage is injected into the device through the water inlet main pipe, sludge enters the reaction area along with the inlet water; the use method comprises a water inlet and outlet stage, an aeration stage and a stirring stage. The invention has the following beneficial effects: rapid formation of aerobic granular sludge can be realized, land is saved, sewage treatment and sludge hydrolysis can be synchronously realized through vertical space design of the tank body, and volatile fatty acid generated by sludge hydrolysis fermentation can improve the concentration of organic matters in a reaction zone so as to improve the nitrogen and phosphorus removal efficiency of biological treatment.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a low-carbon source sewage aerobic granular sludge treatment device and a use method thereof. Background Art

[0002] At present, a large number of urban sewage collection and treatment systems have been built in various cities in my country. Due to the poor quality of pipeline construction, long-term inadequate operation and maintenance, many cities have problems such as pipe siltation, sewage infiltration, and intrusion of external water such as industrial water and surface water, resulting in low influent concentration of terminal sewage treatment plants. At the same time, there is also a common imbalance between the ratio of carbon source and nutrients. It is expected that these drainage network problems will not be fundamentally improved in the long term. At present, most urban sewage treatment plants use biological phosphorus removal and nitrogen removal processes. Since the microbial nitrogen and phosphorus removal process requires the use of organic matter in sewage, the low influent concentration of sewage and the low ratio of carbon source and nutrients will seriously affect the efficiency of biological nitrogen and phosphorus removal. Therefore, in order to meet the discharge water quality standards, sewage treatment plants often need to add a large amount of chemical agents and increase the aeration volume of biological treatment tanks, thereby increasing operating costs and increasing sludge production. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and to propose a low-carbon source sewage aerobic granular sludge treatment device and a method of using the same, which can not only realize the rapid formation of aerobic granular sludge and save land, but also simultaneously realize sewage treatment and sludge hydrolysis through the vertical space design of the pool body. The volatile fatty acids produced by sludge hydrolysis can increase the concentration of organic matter in the reaction device, thereby improving the denitrification and phosphorus removal efficiency of biological treatment.

[0004] The objective of the present invention is achieved through the following technical scheme: a low-carbon source sewage aerobic granular sludge treatment device, comprising a sludge hydrolysis zone and a reaction zone, the sludge hydrolysis zone and the reaction zone are connected in sequence, the sludge hydrolysis zone is located below the reaction zone, there is sludge in the sludge hydrolysis zone, and also includes a water inlet main pipe for supplying water to the reaction zone, the water inlet main pipe is provided with a water inlet pump, when sewage is injected into the device through the water inlet main pipe, the sludge enters the reaction zone with the inlet water.

[0005] It also includes a water distributor connected to the water inlet main pipe.

[0006] A stirring device is arranged in the sludge hydrolysis zone.

[0007] An aeration device is arranged in the reaction zone, and the aeration device is connected with an air supply pipe.

[0008] The water collection tank is a triangular weir water collection tank.

[0009] The water collecting tank is connected with a water outlet pipe.

[0010] The reaction zone is connected with a mud discharge pipe.

[0011] Online monitoring equipment is also provided.

[0012] The water inlet main is communicated with the bottom of the sludge hydrolysis zone.

[0013] A rotating baffle is arranged between the sludge hydrolysis zone and the reaction zone for separating the sludge hydrolysis zone and the reaction zone.

[0014] A reflux pipe is provided at the bottom of the sludge hydrolysis zone, the other end of which is connected to the water inlet main pipe. A reflux pump is provided on the reflux pipe, and the horizontal height of the rotating baffle is lower than the horizontal height of the water inlet main pipe.

[0015] A method for using a low-carbon source sewage aerobic granular sludge treatment device comprises the following steps: S1, water inlet and outlet stage: the sewage is evenly injected into the device from the water inlet main pipe, and the volume content of the injected sewage is 40-60% of the effective working volume of the reaction zone; the sewage enters the device evenly, and under the top support of the inlet water, the sewage flows from the bottom to the top in the form of piston flow, and the clean water on the top of the device is discharged; S2, stirring stage: stirring the sludge hydrolysis area, S3, aeration stage: aeration of the reaction zone; S4, sedimentation stage: stop aeration and sedimentation of the reaction zone, and discharge the flocculent sludge produced by sedimentation.

[0016] The beneficial effects of the present invention are: (1) The present invention proposes an integrated vertically partitioned biological treatment device, which divides the device into functional areas in the vertical direction. The upper part is an aerobic granular sludge reaction area, and the lower part is an anaerobic sludge hydrolysis area, which can save space to a greater extent.

[0017] (2) The present invention sets a rotating baffle between the upper reaction zone and the lower anaerobic sludge hydrolysis zone, which not only ensures that the upper sludge enters the lower hydrolysis zone by gravity, but also avoids the influence of oxygenation on the lower anaerobic environment during the aeration stage, effectively realizing the efficiency of vertical biological functional zoning.

[0018] (3) The lower anaerobic sludge hydrolysis zone of the present invention adopts a multi-bucket water discharge method, which avoids the formation of a sludge dead zone in the sludge hydrolysis zone and the occurrence of methane production.

[0019] (4) The present invention combines sludge hydrolysis with aerobic granular sludge reaction, uses gravity to make the aged sludge at the bottom flow into the sludge hydrolysis zone, and uses a reflux pump to release VFA through sludge hydrolysis and then return it to supplement the carbon source of the influent water. It is suitable for urban sewage with a low carbon-nitrogen ratio, improves the efficiency of phosphorus and nitrogen removal, and at the same time maintains the activity of granular sludge and achieves a certain degree of sludge reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of Embodiment 5 of the present invention; Figure numerals: 1. Water inlet main pipe; 2. Water distributor; 3. Aeration device; 4. Water collecting tank; 5. Air supply pipe; 6. Water outlet pipe; 7. Mud discharge pipe; 8. Stirring device; 10. Online monitoring equipment; 11. Buffer zone; 12. Sludge hydrolysis zone; 13. Reaction zone; 14. Water inlet pump; 15. Flow meter; 16. Rotating baffle; 17. Return pipe; 18. Return pump; 19. Fan; 20. Electric valve; 21. Mud discharge device. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0022] It is to be noted that the concepts of directions “left”, “right”, “up”, “down”, “front”, “back”, “inside” and “outside” in the following schemes are all relative directions and will not be listed one by one here.

[0023] Example 1 A low-carbon source sewage aerobic granular sludge treatment device, reference Figure 1 , including a sludge hydrolysis zone 12, a reaction zone 13 and a water collection tank 4 which are connected in sequence from bottom to top. The sludge at the bottom of the sludge hydrolysis zone 12 is in a layered structure, the lower part is the sludge with larger particle size and relatively aged, and the middle and upper part is the sludge with smaller particle size. The sludge is in an anaerobic state during the water intake process. The bottom of the sludge hydrolysis zone 12 is connected to an inlet main pipe 1, and an inlet pump 14 and a flow meter 15 are arranged on the inlet main pipe 1. A water distributor 2 is arranged at the bottom of the sludge hydrolysis zone 12. The water distributor 2 is connected to the inlet main pipe 1. A stirring device 8 is arranged in the sludge hydrolysis zone 12. The stirring device 8 can be a mechanical stirring device, or it can be replaced by a hydraulic stirring facility.

[0024] An aeration device 3 is provided in the reaction zone 13. The aeration device 3 is connected to an air supply pipe 5, and the air supply pipe 5 is connected to a fan 19. The area between the aeration device 3 and the lower end of the reaction zone 13 is a buffer zone 11. The aeration device 3 aerates upward. A mud discharge device 21 is provided in the reaction zone 13, and the mud discharge device 21 is connected to a mud discharge pipe 7, and an electric valve 20 is provided on the mud discharge pipe 7. An online monitoring device 10 is provided in the reaction zone 13.

[0025] The water collecting tank 4 is a triangular weir water collecting tank. The water collecting tank 4 is connected to a water outlet pipe 6. The effective water depth of the whole device is 10m, of which the effective water depth of the sludge hydrolysis zone is 2m, and the effective water depth of the reaction zone 13 is 8m. The aeration device 3 is installed at the bottom of the reaction zone 13. In actual operation, the height ratio of the reaction zone 13 and the sludge hydrolysis zone 12 can be set according to actual needs.

[0026] Sewage enters the reaction device evenly and slowly through the water inlet main pipe 1 and the water distributor 2. The sewage moves from bottom to top, and the top clean water is discharged into the water collection tank 4. The clean water is discharged from the water collection tank 4 and the outlet pipe 6. During the sewage inflow process, the entire device is in an anaerobic state. On the one hand, the sludge digests the biodegradable organic matter in the inflow water into internal carbon source substances (PHA), and at the same time, the sludge undergoes anaerobic phosphorus release reaction. In addition, the sludge hydrolysis zone 12 at the bottom of the reaction device hydrolyzes in a deep anaerobic state to produce organic carbon sources such as volatile fatty acids (VFAs). , .

[0027] After the water intake is completed, the stirring device 8 is first turned on to mix the sludge hydrolysis zone 12 evenly, and the stirring device 8 is turned off and the aeration device 3 is turned on at the same time. The aeration device 3 provides sufficient dissolved oxygen and hydraulic shear force to flush the sludge, promote the collision and coagulation of the flocculent sludge on the upper part of the reaction zone 13, and accelerate the sludge to secrete a large amount of extracellular polymers to accelerate the granulation process. Since the buffer zone 11 is located between the reaction zone 13 and the sludge hydrolysis zone 12, the VFA substances produced by the sludge hydrolysis in the previous stage are first transferred between the buffer zone 11 and the sewage in the upper reaction zone 13, and then the denitrification and phosphorus removal reaction is carried out above the aeration device 3. During the denitrification and phosphorus removal, it has sufficient required organic carbon sources to ensure the effect of denitrification and phosphorus removal. At the beginning, due to the anaerobic phosphorus release of the sludge, the total phosphorus concentration in the device increased briefly; then due to aeration and the layered structure of aerobic granular sludge (external aerobic layer, middle facultative anoxic layer, internal anaerobic layer), organic matter removal and nitrification reactions, internal denitrification and phosphorus removal reactions occurred in the device, and the sludge degraded organic matter into carbon dioxide and water, and degraded total nitrogen substances into nitrogen gas. , , .

[0028] Close the aeration device 3 to make the sewage in the whole device in a sedimentation state. Open the sludge discharge device 21 and the electric valve 20, and the upper lighter flocculent sludge is discharged from the device under the action of the sedimentation selection pressure, and the heavier granular sludge is retained in the device. In the sedimentation stage, the sludge further undergoes denitrification. .

[0029] Example 2 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 1, comprises the following steps: S1. Sewage is injected into the sludge hydrolysis zone 12 evenly and slowly through the water inlet pipe 1 and the water distributor 2. The sewage flows from the bottom to the top in a piston flow, thereby discharging the clean water in the device in the previous stage to the water collecting tank 4. The clean water leaves the device through the water collecting tank 4 and the water outlet pipe 6. The total volume of the injected sewage is 40% of the effective volume of the entire reaction zone 13, and the duration is 1 hour. S2, the stirring device 8 is started to stir the sludge hydrolysis zone 12 for 0.5h; S3, the stirring device 8 is stopped and the aeration device 3 is started to aerate the reaction zone 13 for 2.0 hours; S4, the aeration device 3 stops, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled upper flocculent sludge.

[0030] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage are 95%, 98%, 70% and 75% respectively.

[0031] Example 3 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 1, comprises the following steps: S1. Sewage is injected into the sludge hydrolysis zone 12 evenly and slowly through the water inlet pipe 1 and the water distributor 2. The sewage flows from the bottom to the top in a piston flow, thereby discharging the clean water in the device in the previous stage to the water collecting tank 4. The clean water leaves the device through the water collecting tank 4 and the water outlet pipe 6. The total volume of the injected sewage is 60% of the effective volume of the reaction zone 13, and the duration is 1.5 hours. S2, the stirring device 8 is started to stir the sludge hydrolysis zone 12 for 0.5h; S3, the stirring device 8 is stopped and the aeration device 3 is started to aerate the reaction zone 13 for 4.5 hours; S4, the aeration device 3 stops, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled upper flocculent sludge.

[0032] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage were 95%, 97%, 72% and 77% respectively.

[0033] Example 4 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 1, comprises the following steps: S1. Sewage is injected into the sludge hydrolysis zone 12 evenly and slowly through the water inlet pipe 1 and the water distributor 2. The sewage flows from the bottom to the top in a piston flow, thereby discharging the clean water in the device in the previous stage to the water collecting tank 4. The clean water leaves the device through the water collecting tank 4 and the water outlet pipe 6. The total volume of the injected sewage is 50% of the effective volume of the reaction zone 13, and the duration is 1 hour. S2, the stirring device 8 is started to stir the sludge hydrolysis zone 12 for 0.5h; S3, the stirring device 8 is stopped and the aeration device 3 is started to aerate the reaction zone 13 for 2.0 hours; S4, the aeration device 3 stops, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled upper flocculent sludge.

[0034] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage were 94%, 92%, 65% and 72% respectively.

[0035] Example 5 In the long-term use of Example 1, although the sewage replenishes the VFA substances produced in the sludge hydrolysis zone 12 and enters the reaction zone 13 during the process of entering the device, there is the following problem: during aeration, since the reaction zone 13 and the sludge hydrolysis zone 12 are not separated, the oxygenation in the aeration stage affects the anaerobic environment of the sludge hydrolysis zone 12, thereby affecting the normal operation of the sludge hydrolysis zone 12.

[0036] In this regard, corresponding improvements are made on the basis of Example 1, referring to Figure 2 The water distributor 2 is arranged between the sludge hydrolysis zone 12 and the reaction zone 13. A rotating baffle 16 is arranged at the lower side of the water distributor 2. A reflux pipe 17 is arranged at the bottom of the sludge hydrolysis zone 12. The reflux pipe 17 is connected to the water inlet main pipe 1. A reflux pump 18 is arranged on the reflux pipe 17.

[0037] During the water inlet process, the rotating baffle 16 is opened, and the reflux pump 18 is turned on to mix the mixed liquid in the sludge hydrolysis zone 12 with the sewage in the water inlet main 1 and then enter the reaction zone 13. The sludge at the bottom of the reaction zone 13 is supplemented into the lower sludge hydrolysis zone 12 under the dual effects of gravity and suction. After the water inlet is completed, the rotating baffle 16 is closed to isolate the sludge hydrolysis zone 12 and the reaction zone 13.

[0038] For those skilled in the art, based on Example 1, the rotary baffle 16 can be only provided in the sludge hydrolysis zone 12 and the reaction zone 13, and the water distributor 2 is still provided at the bottom of the sludge hydrolysis zone 12, without the need to additionally provide a reflux pump 18. When in the water inlet and outlet stage, the rotary baffle 16 is fully opened, and the stirring device 8 of the sludge hydrolysis zone 12 is turned on after the water inlet stage is over. After the mixing is uniform, the rotary baffle 16 is completely closed and the aeration device 3 is turned on.

[0039] Example 6 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 5, comprises the following steps: S1, through the water inlet pipe 1 and the water distributor 2, the sewage and the reflux mixed liquid of the sludge hydrolysis zone 12 are uniformly and slowly continuously injected into the reaction zone 13, the sewage discharges the upper clean water in the previous stage device to the water collecting tank 4, and the clean water is discharged from the device through the water collecting tank 4 and the outlet pipe 6. The total volume of the injected sewage is 40% of the effective volume of the reaction zone 13, the duration is 1h, the rotating baffle 16 is slightly opened, and the reflux pump 18 is turned on; S2. After the water is inletted, the rotating baffle 16 is closed and the stirring device 8 is turned on for stirring for 2.5 hours; S3, the aeration device 3 is started to aerate the reaction zone 13 for 2.5 hours; S4, the stirring device 8 and the aeration device 3 are stopped, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled flocculent sludge.

[0040] Step 2 and step 3 can be performed simultaneously.

[0041] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage were 98%, 99%, 80% and 85% respectively.

[0042] Embodiment 7 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 5, comprises the following steps: S1, through the water inlet pipe 1 and the water distributor 2, the sewage and the reflux mixed liquid of the sludge hydrolysis zone 12 are uniformly and slowly continuously injected into the reaction zone 13, and the sewage discharges the upper clean water in the device of the previous stage to the water collecting tank 4, and the clean water is discharged from the device through the water collecting tank 4 and the water outlet pipe 6. The total volume of the injected sewage is 50% of the volume of the entire device, and the duration is 1h. The rotating baffle 16 is opened and the reflux pump 18 is turned on; S2. After the water is inletted, the rotating baffle 16 is closed and the stirring device 8 is turned on for stirring for 4 hours; S3, the aeration device 3 is started to aerate the reaction zone 13 for 4 hours; S4, the stirring device 8 and the aeration device 3 are stopped, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled flocculent sludge.

[0043] Step 2 and step 3 can be performed simultaneously.

[0044] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage were 98%, 99%, 82% and 87% respectively.

[0045] Embodiment 8 A method for using a low-carbon source sewage aerobic granular sludge treatment device, based on the device of Example 5, comprises the following steps: S1 evenly and slowly injects sewage and the reflux mixture of the sludge hydrolysis zone 12 into the reaction zone 13 through the water inlet main 1 and the water distributor 2. The sewage discharges the upper clean water in the device of the previous stage to the water collection tank 4. The clean water is discharged from the device through the water collection tank 4 and the outlet pipe 6. The total volume of the injected sewage is 60% of the volume of the entire device. The duration is 1.5 hours. The rotating baffle 16 is slightly opened and the reflux pump 18 is turned on. S2, after the water is inletted, the rotating baffle 16 is closed, and the stirring device 8 is turned on for stirring for 5 hours; S3, the aeration device 3 is started to aerate the reaction zone 13 for 5 hours; S4, the stirring device 8 and the aeration device 3 are stopped, and after settling for 0.5 hours, the electric valve 20 is opened to discharge the settled flocculent sludge.

[0046] Step 2 and step 3 can be performed simultaneously.

[0047] After treatment by this method, the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage were 98%, 99%, 85% and 90% respectively.

[0048] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above description or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A low-carbon source sewage aerobic granular sludge treatment device, comprising a sludge hydrolysis zone and a reaction zone, characterized in that: The sludge hydrolysis zone and the reaction zone are connected in sequence. The sludge hydrolysis zone is located below the reaction zone. Sludge exists in the sludge hydrolysis zone. The sludge hydrolysis zone also includes a water inlet pipe for supplying water to the reaction zone. A water inlet pump is arranged on the water inlet pipe. When sewage is injected into the device through the water inlet pipe, the sludge enters the reaction zone along with the inlet water. A stirring device is arranged in the sludge hydrolysis zone.

2. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1 is characterized by: A rotating baffle is arranged between the sludge hydrolysis zone and the reaction zone for separating the sludge hydrolysis zone and the reaction zone.

3. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1 is characterized by: It also includes a water distributor connected to the water inlet main pipe.

4. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1, characterized in that: An aeration device is arranged in the reaction zone, and the aeration device is connected with an air supply pipe.

5. The low-carbon source sewage aerobic granular sludge treatment device according to claim 2, characterized in that: A reflux pipe is provided at the bottom of the sludge hydrolysis zone, the other end of which is connected to the water inlet main pipe. A reflux pump is provided on the reflux pipe, and the horizontal height of the rotating baffle is lower than the horizontal height of the water inlet main pipe.

6. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1, characterized in that: A water collecting tank is arranged above the reaction zone, and a water outlet pipe is arranged above the water collecting tank.

7. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1, characterized in that: A mud discharge device is arranged in the reaction zone, and the mud discharge device is arranged at a height slightly above the middle of the reaction zone. A mud discharge pipe is arranged on the reaction zone, and the mud discharge pipe is connected to the mud discharge device. An electric valve is arranged on the mud discharge pipe.

8. The low-carbon source sewage aerobic granular sludge treatment device according to claim 1, characterized in that: The water inlet main is communicated with the bottom of the sludge hydrolysis zone.

9. A method for using the low-carbon source sewage aerobic granular sludge treatment device according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, water inlet and outlet stage: the sewage is evenly injected into the device from the water inlet main pipe, and the volume content of the injected sewage is 40-60% of the effective working volume of the reaction zone; the sewage enters the device evenly, and under the top support of the inlet water, the sewage flows from the bottom to the top in the form of piston flow, and the clean water on the top of the device is discharged; S2, stirring stage: stirring the sludge hydrolysis zone, which can be continuous or intermittent; S3, aeration stage: aeration of the reaction zone; S4, sedimentation stage: stop aeration and sedimentation of the reaction zone, and discharge the flocculent sludge produced by sedimentation.

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