Method for preserving granular sludge and start-up device thereof

Abstract

This invention discloses a method for preserving granular sludge and its start-up equipment. The method includes the following steps: S1, sludge collection; S2, addition of reagents; S3, storage; S4, detection and circulation. The equipment includes a ring-shaped reactor with several cavities inside, first drive wheels located on both sides of the reactor, the first drive wheels being driven to rotate by a first drive motor and clamped and fixed by two fixed plates, the rear side of the first drive motor being fixedly connected to one fixed plate, and the rear end of an auxiliary shaft being rotatably connected to the inner wall of another fixed plate, and a second drive wheel being fixedly connected to the outer sides of the two fixed plates for rotating the reactor. The preservation method provided by this invention is not only an effective long-term storage solution, but also a key technology to ensure the efficient start-up and stable operation of an anaerobic ammonia oxidation reactor.

Description

Technical Field

[0001] This invention relates to the field of sludge regeneration technology, specifically to a method for preserving granular sludge and its start-up equipment. Background Technology

[0002] In traditional wastewater treatment, nitrogen removal mainly relies on nitrification-denitrification, a process that requires large amounts of oxygen, carbon sources, and energy, resulting in high operating costs. Anaerobic ammonia oxidation (AAO) technology offers a more economical nitrogen removal pathway. Driven by specific microorganisms, AAO directly converts ammonia nitrogen into nitrogen gas under anaerobic conditions, significantly reducing the demand for oxygen and carbon sources.

[0003] Despite the significant economic and environmental advantages of anammox technology, several challenges exist during its start-up and operation. The long generation time of anammox bacteria, approximately 14.4 to 32.1 days, results in a prolonged start-up and stable operation of the anammox reactor (1). Furthermore, anammox bacteria are sensitive to environmental conditions such as temperature, pH, and salinity changes, all of which affect their activity and performance. Therefore, to shorten the start-up time of reactor (1) and maintain the activity of the anammox sludge, effective preservation methods for the anammox sludge are necessary. The preservation status of granular sludge also directly affects the start-up efficiency and operational stability of the anammox reactor. The start-up of the anammox reactor is a complex process requiring a suitable microbial community and the activity of functional genes.

[0004] Existing methods for preserving anammox sludge include freezing and lyophilization, but these methods not only increase preservation costs but may also lead to irreversible inactivation of anammox bacteria during long-term storage. Furthermore, while the optimal growth temperature for anammox bacteria is 30–40°C, preservation experiments have shown that preserving anammox sludge at temperatures between 4 and 30°C is more feasible. Although studies have explored the effects of different preservation conditions on the activity of anammox granular sludge, these studies are generally limited to short-term preservation, and little is known about the impact on microbial communities and functional genes under long-term preservation conditions. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for preserving granular sludge and its start-up device.

[0006] The technical solution of this invention is:

[0007] A method for preserving granular sludge includes the following steps:

[0008] S1. Sludge collection: Collect anaerobic ammonium oxidation-hydroxyapatite granular sludge and wash it with deionized water 2-3 times to remove impurities.

[0009] S2. Adding agents: Add protective agents to the cleaned anammox-hydroxyapatite granular sludge. The protective agents include molybdate, glycerol, and distilled water. After mixing, they form a granular sludge protection system. The molar concentration of molybdate in the granular sludge protection system is 5-10 mM, the mass fraction of glycerol is 10-15%, and the VSS concentration of the anammox-hydroxyapatite granular sludge is 55-60 g VSS / L.

[0010] S3. Storage: Transfer the granular sludge protection system to the start-up equipment for storage. The storage temperature is controlled at 3-5°C, and vacuum and light-proof conditions are maintained.

[0011] S4. Detection and circulation: Periodically sample the granular sludge protection system in the start-up equipment to detect the preservation effect of anaerobic ammonia oxidation-hydroxyapatite granular sludge and changes in microbial community structure. During periodic testing, circulate the granular sludge protection system in the start-up equipment. After the granular sludge protection system is extracted, it is separated by a three-phase separator and the supernatant and gas are discarded.

[0012] Furthermore, the starting device in S3 continuously rotates and stirs during storage to maintain the uniform suspension state of the anaerobic ammonium oxidation-hydroxyapatite granular sludge in the granular sludge protection system, with a rotation speed of 5 to 20 rpm.

[0013] Note: Continuous stirring prevents the deposition of anaerobic ammonia oxidation-hydroxyapatite granular sludge in the granular sludge protection system.

[0014] Furthermore, during storage in S3, the internal aeration of the start-up equipment is performed once every 6 to 12 hours, and the aeration rate is controlled so that the dissolved oxygen content in the granular sludge protection system is ≤0.2 mg / L.

[0015] Note: For the anammox process, since it is an anaerobic process, theoretically no additional oxygen is required. However, in actual operation, moderate aeration may be necessary to maintain the activity of microorganisms in the bioreactor and prevent adverse metabolic activities. The dissolved oxygen (DO) setting should generally be kept at a low level to ensure the maintenance of the anaerobic environment and to ensure that the normal metabolic activities of anaerobic microorganisms are not affected by oxygen.

[0016] Furthermore, in S4, the detection cycle is 0.25d to 30d, and the method for detecting the preservation effect is to detect the specific anaerobic ammonia oxidation activity (SAA) of the anaerobic ammonia oxidation-hydroxyapatite granular sludge; the method for detecting changes in the microbial community structure is to detect changes in sulfur reduction genes (dcyD and NADPH) through functional gene analysis.

[0017] Furthermore, the molybdate is sodium molybdate, and in step S4, sodium molybdate is replenished during periodic testing to ensure that the molar concentration of sodium molybdate in the granular sludge protection system is 5-10 mM.

[0018] Note: Regularly adding sodium molybdate inhibits the expression of sulfur reduction genes, preventing granular sludge from turning black.

[0019] The present invention also provides a granular sludge preservation start-up device for implementing the granular sludge preservation method described in any one of the above claims, comprising an annular reactor with a plurality of cavities inside, and first drive wheels located on both sides of the reactor, wherein the teeth of the first drive wheels mesh with teeth provided on the outer wall of the reactor to rotate the reactor.

[0020] The first drive wheel is driven to rotate by the first drive motor and is clamped and fixed by two fixed plates. The center of one side of the first drive wheel is connected to the output shaft of the first drive motor, and an auxiliary shaft is provided at the center of the other side of the first drive wheel. The rear side of the first drive motor is fixedly connected to one of the fixed plates, and the rear end of the auxiliary shaft is rotatably connected to the inner wall of the other fixed plate. A second drive wheel is fixedly connected to the outer side of the two fixed plates to make the reactor rotate.

[0021] The center points of the two second drive wheels are on the same straight line as the center of the reactor. An extension plate is provided on the outer wall of the front side of the fixed plate, and a fixed rod is provided on the inner wall of the extension plate. An arc-shaped slider is provided at the end of the fixed rod, and the arc-shaped slider is slidably connected to the groove provided on the side wall of the reactor.

[0022] Each of the reactors located on both sides of the cavity is provided with a partition plate. The partition plate is slidably and sealingly connected to the groove provided on the inner wall of the reactor. An inlet is provided on the inner wall of the reactor between the two partition plates.

[0023] Furthermore, the grooves on both sides of the reactor are of the same depth, and the side of the arc-shaped slider that fits into the groove is provided with an auxiliary roller.

[0024] Explanation: The sliding connection between the arc-shaped slider and the chute not only keeps the reactor stable during rotation, but also provides some support during the rotation process.

[0025] Furthermore, the second drive wheel is driven to rotate by a second drive motor. The output end of the second drive motor is provided with a drive gear. The teeth of the drive gear mesh with the teeth provided on the outer wall of the second drive wheel. The drive gear is located at the top of the second drive wheel.

[0026] The second drive wheel has a support wheel on each side of its bottom. The teeth of the support wheel mesh with the teeth on the outer wall of the second drive wheel. A support seat is provided below the support wheel, and the support wheel is located in a slot in the middle of the support seat. The two sides of the support wheel are rotatably connected to the inner wall of the slot through a rotating shaft.

[0027] A reinforcing shaft is rotatably connected at the center of the rear side of the second drive wheel;

[0028] A fixed frame is provided below the reactor. An extension groove is provided in the middle of the fixed frame to provide rotation space for the reactor. The fixed frame on both sides of the extension groove has stepped surfaces inside. Each of the support seats is fixed on the two stepped surfaces respectively. The second drive motor and the reinforcing shaft are both fixed on the inner wall of the fixed frame above the stepped surfaces.

[0029] Explanation: The second drive wheel and its related structural components enable the reactor to rotate, and while maintaining rotation, the reactor also rotates itself, thereby maintaining uniform mixing of the internal granular sludge protection system.

[0030] Furthermore, a positioning rod is provided on the inner wall of the reactor on both sides of the partition, and a baffle is connected to the top of the positioning rod. A threaded rod is rotatably connected to the top of the partition, and the threaded rod passes through the middle of the baffle and is rotatably connected to the baffle with threads. A top cover is provided on the top of the threaded rod. A check valve is provided in each liquid inlet, and a detection head is provided on the inner wall of the reactor corresponding to each cavity.

[0031] Note: The opening and closing of the baffle is controlled by the threaded rod, which facilitates the overall cleaning and liquid replacement of the reactor.

[0032] The beneficial effects of this invention are:

[0033] (1) The granular sludge preservation method and start-up equipment of the present invention can ensure that the anammox-hydroxyapatite granular sludge maintains high activity and integrity of microbial community structure after long-term storage, which is crucial for rapid reactor start-up. During the reactor start-up stage, the use of granular sludge treated with optimized preservation conditions can significantly shorten the start-up time, reducing the reactor start-up time by more than 40% compared with traditional preservation methods, because the microorganisms in these sludges have adapted to the anammox environment and their activity is well maintained. In addition, the protective agents added during the preservation process, such as molybdate and glycerol, not only help maintain the activity of the sludge, but also reduce the stress response of microorganisms during reactor start-up, thereby improving the start-up success rate. After the reactor is started, these preserved granular sludges can quickly adapt to the operating conditions of the reactor and rapidly restore their anammox function, reducing the risk of nitrogen removal efficiency decline due to microbial community reconstruction. The preservation method provided by the present invention is not only an effective long-term storage solution, but also a key technology to ensure efficient start-up and stable operation of anammox reactors.

[0034] (2) The present invention provides a granular sludge storage method and its start-up device to address the problem that the reactor cannot be vigorously stirred when storing granular sludge. It provides a self-rotating and rotating device, so as to complete the uniform mixing of granular sludge without stirring, avoid sludge deposition, maintain good activity, and is easy to operate with a high degree of automation. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the overall structure of a granular sludge preservation and start-up device according to the present invention;

[0036] Figure 2 This is a front view of a granular sludge preservation and start-up device according to the present invention;

[0037] Figure 3 This is a top view of a granular sludge preservation and start-up device according to the present invention;

[0038] Figure 4 This is a schematic diagram of the structure of the partition plate on the inner wall of the reactor in a granular sludge storage and start-up device according to the present invention;

[0039] Figure 5 This is a schematic diagram of a partial internal structure of the reactor in a granular sludge preservation and start-up device according to the present invention;

[0040] Figure 6 This is a partial structural diagram of the reactor internal partition of the granular sludge preservation and start-up device of the present invention when it is opened;

[0041] Figure 7This is a schematic diagram of the auxiliary roller structure inside the arc-shaped slider of a granular sludge preservation and start-up device according to the present invention;

[0042] Figure 8 This is a schematic diagram of the support structure of a granular sludge preservation and start-up device according to the present invention;

[0043] Figure 9 This is a comparison chart of the preservation effect of granular sludge in the experimental examples of this invention.

[0044] Among them, 1-reactor, 11-cavity, 12-slide groove, 13-partition, 14-slot, 15-liquid inlet, 16-detection head, 2-fixed frame, 21-extension groove, 22-step surface, 3-first drive wheel, 31-first drive motor, 32-auxiliary shaft, 4-fixed plate, 41-extension plate, 42-fixed rod, 43-arc slider, 44-auxiliary roller, 5-second drive wheel, 51-second drive motor, 52-drive gear, 53-support wheel, 54-rotating shaft, 55-reinforcing shaft, 6-support seat, 61-groove, 7-baffle, 71-positioning rod, 8-threaded rod, 81-top cover. Detailed Implementation

[0045] Example 1

[0046] A method for preserving granular sludge includes the following steps:

[0047] S1. Sludge collection: Collect anaerobic ammonium oxidation-hydroxyapatite granular sludge and wash it three times with deionized water to remove impurities.

[0048] S2. Adding agents: Add protective agents to the cleaned anammox-hydroxyapatite granular sludge. The protective agents include sodium molybdate, glycerol, and distilled water. After mixing, they form a granular sludge protection system. The molar concentration of sodium molybdate in the granular sludge protection system is 8 mM, the mass fraction of glycerol is 12%, and the VSS concentration of the anammox-hydroxyapatite granular sludge is 57.4 g VSS / L.

[0049] S3. Storage: Transfer the granular sludge protection system to the start-up equipment for storage. The storage temperature is controlled at 4℃, and vacuum and light-proof conditions are maintained. During storage in S3, the start-up equipment is continuously rotated and stirred to maintain the uniform suspension state of the anaerobic ammonium oxidation-hydroxyapatite granular sludge in the granular sludge protection system. The rotation speed is 10 rpm. During storage in S3, the start-up equipment is aerated once every 8 hours, and the aeration rate is controlled to keep the dissolved oxygen content in the granular sludge protection system at 0.05 mg / L.

[0050] S4. Detection Cycle: Periodically sample the granular sludge protection system in the start-up equipment, with a detection cycle of 5 days. Detect the preservation effect and microbial community structure changes of the anammox-hydroxyapatite granular sludge. The detection method for preservation effect is to detect the specific anammox activity (SAA) of the anammox-hydroxyapatite granular sludge. The detection method for changes in microbial community structure is to detect changes in sulfur reduction genes (dcyD and NADPH) through functional gene analysis. During periodic detection, circulate the granular sludge protection system in the start-up equipment. After the granular sludge protection system is extracted, it is separated by a three-phase separator, and the supernatant and gas are discarded. During periodic detection, add sodium molybdate to ensure that the molar concentration of sodium molybdate in the granular sludge protection system is 8 mM.

[0051] Example 2

[0052] The difference between this embodiment and Embodiment 1 is that:

[0053] S1. Sludge collection: Collect anaerobic ammonium oxidation-hydroxyapatite granular sludge and wash it twice with deionized water to remove impurities.

[0054] The granular sludge protection system contains sodium molybdate at a concentration of 5 mM, glycerol at a mass fraction of 10%, and anaerobic ammonia oxidation-hydroxyapatite granular sludge with a VSS concentration of 55 g VSS / L.

[0055] Example 3

[0056] The difference between this embodiment and Embodiment 1 is that:

[0057] The granular sludge protection system contains sodium molybdate at a concentration of 10 mM, glycerol at a mass fraction of 15%, and anaerobic ammonia oxidation-hydroxyapatite granular sludge with a VSS concentration of 60 g VSS / L.

[0058] Example 4

[0059] The difference between this embodiment and Embodiment 1 is that:

[0060] S3. Storage: The storage temperature is controlled at 3℃, the rotation speed is 5rpm, and the equipment is aerated once every 6 hours. The aeration rate is controlled so that the dissolved oxygen content in the granular sludge protection system is 0.1mg / L.

[0061] Example 5

[0062] The difference between this embodiment and Embodiment 1 is that:

[0063] S3. Storage: The storage temperature is controlled at 5℃, the rotation speed is 20rpm, and the equipment is aerated once every 12 hours. The aeration rate is controlled so that the dissolved oxygen content in the granular sludge protection system is 0.2mg / L.

[0064] Note: In Examples 1 to 5, the given parameter ranges have been refined. In actual operation, the control of each parameter may not be so accurate. Therefore, it is sufficient to control the above parameters within the parameter range given in this invention.

[0065] Example 6

[0066] The difference between this embodiment and Embodiment 1 is that:

[0067] S4. Testing Cycle: The granular sludge protection system in the start-up equipment is sampled periodically, with a testing cycle of 0.25 days. Sodium molybdate is added during periodic testing to ensure that the molar concentration of sodium molybdate in the granular sludge protection system is 5 mM.

[0068] Example 7

[0069] The difference between this embodiment and Embodiment 1 is that:

[0070] S4. Testing Cycle: The granular sludge protection system in the start-up equipment is sampled periodically, with a testing cycle of 30 days. Sodium molybdate is added during periodic testing to ensure that the molar concentration of sodium molybdate in the granular sludge protection system is 10 mM.

[0071] Note: In Examples 6 and 7, the periodic testing cycle should be reasonably selected as needed. If the storage time is long, the testing cycle can be appropriately extended.

[0072] Example 8

[0073] This embodiment provides a granular sludge preservation start-up device to implement a granular sludge preservation method as described in Embodiment 1, such as... Figure 1 and Figure 5 As shown, the reactor 1 includes an annular structure with eight cavities 11 inside, and first drive wheels 3 located on both sides of the reactor 1. The teeth of the first drive wheels 3 mesh with the teeth on the outer wall of the reactor 1 to make the reactor 1 rotate.

[0074] like Figure 1 and Figure 2 As shown, the first drive wheel 3 is driven to rotate by the first drive motor 31 and is clamped and fixed by two fixing plates 4. The center of one side of the first drive wheel 3 is connected to the output shaft of the first drive motor 31, and the center of the other side of the first drive wheel 3 is provided with an auxiliary shaft 32. The rear side of the first drive motor 31 is fixedly connected to a fixing plate 4, and the rear end of the auxiliary shaft 32 is rotatably connected to the inner wall of another fixing plate 4. A second drive wheel 5 is fixedly connected to the outer side of the two fixing plates 4 to make the reactor 1 rotate.

[0075] like Figure 1 , Figure 3 and Figure 7 As shown, the center points of the two second drive wheels 5 are on the same straight line as the center of the reactor 1. An extension plate 41 is provided on the outer wall of the front side of the fixed plate 4. A fixed rod 42 is provided on the inner wall of the extension plate 41. An arc-shaped slider 43 is provided at the end of the fixed rod 42. The arc-shaped slider 43 is slidably connected to the groove 12 provided on the side wall of the reactor 1. The grooves 12 provided on both sides of the reactor 1 have the same depth. An auxiliary roller 44 is provided on the side of the arc-shaped slider 43 that is in contact with the groove 12.

[0076] like Figure 5 and Figure 6 As shown, each reactor 1 on both sides of each cavity 11 is provided with a baffle 13. The baffle 13 slides and is sealed to the groove 14 on the inner wall of the reactor 1. An inlet 15 is provided on the inner wall of the reactor 1 between the two baffles 13. A positioning rod 71 is provided on the inner wall of the reactor 1 on both sides of the baffle 13. A baffle 7 is connected to the top of the positioning rod 71. A threaded rod 8 is rotatably connected to the top of the baffle 13. The threaded rod 8 passes through the middle of the baffle 7 and is threadedly rotatably connected to the baffle 7. A top cover 81 is provided on the top of the threaded rod 8. A check valve is provided in each inlet 15. A detection head 16 is provided on the inner wall of the reactor 1 corresponding to each cavity 11. The detection head 16 is a commercially available product used to detect the pH, dissolved oxygen, temperature and ORP of the granular sludge protection system in the cavity, and is electrically connected to an external commercially available monitoring system.

[0077] like Figure 1 As shown, the second drive wheel 5 is driven to rotate by the second drive motor 51. The output end of the second drive motor 51 is provided with a drive gear 52. The teeth of the drive gear 52 mesh with the teeth provided on the outer wall of the second drive wheel 5. The drive gear 52 is located at the top of the second drive wheel 5.

[0078] like Figure 2 and Figure 8 As shown, a support wheel 53 is provided on each side of the bottom of the second drive wheel 5. The teeth of the support wheel 53 mesh with the teeth provided on the outer wall of the second drive wheel 5. A support seat 6 is provided below the support wheel 53, and the support wheel 53 is located in the slot 61 provided in the middle of the support seat 6. Each side of the support wheel 53 is rotatably connected to the inner wall of the slot 61 through a rotating shaft 54.

[0079] like Figure 1 As shown, a reinforcing shaft 55 is rotatably connected at the center of the rear side of the second drive wheel 5;

[0080] like Figure 1 and Figure 4As shown, a fixed frame 2 is provided below the reactor 1. An extension groove 21 is provided in the middle of the fixed frame 2 to provide rotation space for the reactor 1. The fixed frame 2 on both sides of the extension groove 21 has stepped surfaces 22 inside. Each support seat 6 is fixed on the two stepped surfaces 22 respectively. The second drive motor 51 and the reinforcing shaft 55 are both fixed on the inner wall of the fixed frame 2 above the stepped surface 22. The first drive motor 31 and the second drive motor 51 are both commercially available gear reduction motors.

[0081] Example 9

[0082] The difference between this embodiment and Embodiment 1 is that:

[0083] The reactor 1 has 12 cavities 11 inside.

[0084] Note: The number of cavities 11 can be adjusted arbitrarily, but should be controlled within a reasonable range. In particular, when the granular sludge protection system is large, more cavities mean an increase in the number of components such as baffles 13 and baffles 7, which increases the overall load on reactor 1, making it consume more power and increase the failure rate during rotation. On the other hand, too few cavities 11 may lead to uneven mixing and sedimentation of granular sludge. Therefore, it is advisable to select 8 to 12 cavities 11.

[0085] Working principle:

[0086] The working principle of the device of the present invention will be further explained below in conjunction with the method of the present invention.

[0087] During S2, the granular sludge protection system is added by connecting the external pipeline to the inlet 15. At this time, the baffle 13 is in the closed state. Therefore, the same volume of granular sludge protection system can be added through each inlet 15 in sequence. The granular sludge protection system occupies 90% of the internal space of the cavity 11.

[0088] During S3, the stirring mentioned therein is achieved by rotating and self-rotating reactor 1 to achieve the same purpose as stirring: the two first drive motors 31 are turned on synchronously in opposite directions, causing the first drive wheel 3 to rotate, thereby realizing the self-rotation of reactor 1. At the same time, the second drive motor 51 is turned on, causing the second drive wheel 5 to rotate, which in turn drives reactor 1 to rotate under the action of fixed plate 4 and arc-shaped slider 43. It should be noted that when not rotating, reactor 1 remains upright. At this time, the two arc-shaped sliders 43 can provide support through friction. Together with the support base 6, they are sufficient to support a weight of more than 200 kg, which is sufficient for the requirements of granular sludge protection system for industrial production. Alternatively, multiple reactors 1 can be configured adjacent to each other to achieve the purpose of industrial production.

[0089] During the rotation of reactor 1, the two arc-shaped sliders 43 are assisted by auxiliary rollers 44 to slide within the groove 12. Especially when the reactor 1 is rotated to a horizontal position, the lower arc-shaped slider 43 has to bear a greater weight. Therefore, the connection strength between the arc-shaped slider 43 and the extension plate 42, between the extension plate 42 and the fixed plate 4, and between the fixed plate 4 and the second drive wheel 5 needs to be guaranteed. High-strength alloy can be used.

[0090] Temperature control during storage is achieved by placing the entire reactor 1 inside a cold storage room, or by mounting a temperature regulator above the extension trough 21 of the fixed frame 2 to control the internal temperature of the reactor 1.

[0091] During S4, periodic sampling is performed by stopping the rotation and self-rotation of reactor 1 to keep it upright. Samples are then taken sequentially from the inlet 15 through external pipelines and a pump. The detection head 16 is a commercially available product used to detect the pH, dissolved oxygen, temperature, and ORP of the granular sludge protection system inside the cavity. It is electrically connected to an external commercially available monitoring system to achieve automated real-time monitoring. The addition of sodium molybdate is also done through the inlet 15, and aeration is also done by connecting an external air pump to the inlet 15.

[0092] After a storage cycle is completed, reactor 1 needs to be cleaned. At this time, the granular sludge protection system inside each cavity 11 is emptied in sequence, and the top cover 81 is rotated to make the threaded rod 8 rotate and rise inside the baffle 7, thereby opening each partition 13. Water is then injected through a liquid inlet 15 to complete the overall cleaning of the inside of reactor 1.

[0093] Experimental Example

[0094] Below, we conducted actual tests using the method in Example 1 and the equipment in Example 8. Anaerobic ammonia oxidation-hydroxyapatite granular sludge was collected from a laboratory-scale extended granular sludge bed (EGSB) mother reactor and stored for 6 months. Samples were taken at days 0, 20, 40, 60, 80, and 100 of the storage period for specific anaerobic ammonia oxidation (SAA) activity tests to monitor activity decay and compare the results with those of conventional storage methods, which involve maintaining temperature and agitation without adding any auxiliary additives. The results are as follows... Figure 9 As shown;

[0095] It can be seen that by adopting the method and equipment of this invention, the activity of anammox-hydroxyapatite granular sludge is significantly better maintained, with a noticeable difference after 30 days of storage and a nearly 15% difference in activity after 100 days of storage. This indicates that the preservation method provided by this invention is not only an effective long-term storage solution, but also a key technology to ensure the efficient start-up and stable operation of the anammox reactor.

Claims

1. A granular sludge preservation and start-up device, characterized in that, The reactor (1) includes a ring-shaped reactor with several cavities (11) inside, and first drive wheels (3) located on both sides of the reactor (1). The teeth of the first drive wheels (3) mesh with the teeth on the outer wall of the reactor (1) to make the reactor (1) rotate. The first drive wheel (3) is driven to rotate by the first drive motor (31) and is clamped and fixed by two fixed plates (4). The center of one side of the first drive wheel (3) is connected to the output shaft of the first drive motor (31), and an auxiliary shaft (32) is provided at the center of the other side of the first drive wheel (3). The rear side of the first drive motor (31) is fixedly connected to one of the fixed plates (4), and the rear end of the auxiliary shaft (32) is rotatably connected to the inner wall of another fixed plate (4). A second drive wheel (5) is fixedly connected to the outer side of the two fixed plates (4) to make the reactor (1) rotate. The center points of the two second drive wheels (5) are on the same straight line as the center of the reactor (1). The outer wall of the front side of the fixed plate (4) is provided with an extension plate (41). The inner wall of the extension plate (41) is provided with a fixed rod (42). The end of the fixed rod (42) is provided with an arc-shaped slider (43). The arc-shaped slider (43) is slidably connected to the groove (12) provided on the side wall of the reactor (1). Each reactor (1) on both sides of each cavity (11) is provided with a partition (13). The partition (13) slides and is sealed to the groove (14) provided on the inner wall of the reactor (1). An inlet (15) is provided on the inner wall of the reactor (1) between the two partitions (13).

2. The granular sludge preservation and start-up device according to claim 1, characterized in that, The grooves (12) on both sides of the reactor (1) are of the same depth, and the side of the arc-shaped slider (43) that is in contact with the groove (12) is provided with an auxiliary roller (44).

3. The granular sludge preservation and start-up device according to claim 1, characterized in that, The second drive wheel (5) is driven to rotate by the second drive motor (51). The output end of the second drive motor (51) is provided with a drive gear (52). The teeth of the drive gear (52) mesh with the teeth provided on the outer wall of the second drive wheel (5). The drive gear (52) is located on the top of the second drive wheel (5). The second drive wheel (5) has a support wheel (53) on each side of its bottom. The teeth of the support wheel (53) mesh with the teeth on the outer wall of the second drive wheel (5). A support seat (6) is provided below the support wheel (53), and the support wheel (53) is located in the slot (61) in the middle of the support seat (6). The two sides of the support wheel (53) are rotatably connected to the inner wall of the slot (61) through a rotating shaft (54). A reinforcing shaft (55) is rotatably connected at the rear center of the second drive wheel (5); A fixed frame (2) is provided below the reactor (1). An extension groove (21) is provided in the middle of the fixed frame (2) to provide rotation space for the reactor (1). The fixed frame (2) on both sides of the extension groove (21) is provided with stepped surfaces (22). Each of the support seats (6) is fixed on the two stepped surfaces (22) respectively. The second drive motor (51) and the reinforcing shaft (55) are both fixed on the inner wall of the fixed frame (2) above the stepped surfaces (22).

4. The granular sludge preservation and start-up device according to claim 1, characterized in that, On the inner wall of the reactor (1) on both sides of the partition (13), there is a positioning rod (71). The top of the positioning rod (71) is connected to a baffle (7). The top of the partition (13) is rotatably connected to a threaded rod (8). The threaded rod (8) passes through the middle of the baffle (7) and is rotatably connected to the baffle (7). The top of the threaded rod (8) is provided with a top cover (81). Each liquid inlet (15) is provided with a check valve. A detection head (16) is provided on the inner wall of the reactor (1) corresponding to each cavity (11).

5. A method for preserving granular sludge, implemented based on the granular sludge preservation start-up device according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Sludge collection: Collect anaerobic ammonium oxidation-hydroxyapatite granular sludge and wash it with deionized water 2-3 times to remove impurities. S2. Adding agents: Add protective agents to the cleaned anammox-hydroxyapatite granular sludge. The protective agents include molybdate, glycerol, and distilled water. After mixing, they form a granular sludge protection system. The molar concentration of molybdate in the granular sludge protection system is 5-10 mM, the mass fraction of glycerol is 10-15%, and the VSS concentration of the anammox-hydroxyapatite granular sludge is 55-60 g VSS / L. S3. Storage: Transfer the granular sludge protection system to the start-up equipment for storage. The storage temperature is controlled at 3~5℃, and vacuum and light-proof conditions are maintained. S4. Detection and circulation: Periodically sample the granular sludge protection system in the start-up equipment to detect the preservation effect of anaerobic ammonia oxidation-hydroxyapatite granular sludge and changes in microbial community structure. During periodic testing, circulate the granular sludge protection system in the start-up equipment. After the granular sludge protection system is extracted, it is separated by a three-phase separator and the supernatant and gas are discarded.

6. A method for preserving granular sludge according to claim 5, characterized in that, The starting device in S3 continuously rotates and stirs during storage to maintain the uniform suspension state of the anaerobic ammonia oxidation-hydroxyapatite granular sludge in the granular sludge protection system. The rotation speed is 5~20 rpm.

7. A method for preserving granular sludge according to claim 5, characterized in that, During storage in S3, the internal equipment is aerated once every 6 to 12 hours, and the aeration rate is controlled so that the dissolved oxygen content in the granular sludge protection system is ≤0.2 mg / L.

8. A method for preserving granular sludge according to claim 5, characterized in that, In S4, the detection cycle is 0.25d~30d. The method for detecting the preservation effect is to detect the specific anaerobic ammonia oxidation activity (SAA) of the anaerobic ammonia oxidation-hydroxyapatite granular sludge. The method for detecting changes in the microbial community structure is to detect changes in sulfur reduction genes (dcyD and NADPH) through functional gene analysis.

9. A method for preserving granular sludge according to claim 5, characterized in that, The molybdate is sodium molybdate. In step S4, sodium molybdate is added during periodic testing to ensure that the molar concentration of sodium molybdate in the granular sludge protection system is 5~10mM.

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