Sludge granulation process and system in main stream area of sewage plant

Abstract

The application discloses a sludge granulation process and system for a main flow area of a sewage plant, and relates to the technical field of sewage treatment.The process comprises the following steps: S1, sludge is taken out from a main flow tank responsible for precipitation by a sludge discharge mechanism, and is temporarily stored in a sludge tank; S2, sludge is taken from the sludge tank by a pre-sludge circulation mechanism, and water is taken from a drainage area of the main flow tank by a water circulation pipeline; S3, sludge in a stable proportioning tank is taken by a composite spiral feeder with at least one stirring section, water above the sludge in the stable proportioning tank is taken by a post-water distribution pipeline and is sent to the stirring section of the composite spiral feeder for mixing; S4, a mixture taken out from the composite spiral feeder is received by a cyclone module and is subjected to sludge concentration and screening; and S5, sludge generated in S4 is taken and is divided into a granulation group and a recirculation group.The application has the effect of reducing the influence of unstable sewage components on sludge granulation.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, and in particular to a sludge granulation process and system for the main zone of a wastewater treatment plant. Background Technology

[0002] Various types of wastewater are generated in daily production and life. If the wastewater is directly discharged into rivers, seas and other water bodies, the nitrogen and phosphorus pollutants it contains can easily cause problems such as eutrophication and decreased dissolved oxygen, which in turn leads to water quality deterioration and environmental pollution. Therefore, it is necessary to treat the wastewater before it is discharged in compliance with standards or to utilize it as a resource.

[0003] Currently, the activated sludge process is a method of biological wastewater treatment, and it and its derivative improved processes are the most widely used methods for treating urban wastewater. The activated sludge process involves continuously mixing and cultivating wastewater and various microbial communities under artificial aeration conditions to form activated sludge. The activated sludge utilizes its bio-flocculation, adsorption, and oxidation properties to decompose and remove organic pollutants from the wastewater.

[0004] Aerobic granular sludge is a secondary processed product of the above-mentioned activated sludge. Compared with traditional activated sludge flocs, aerobic granular sludge has the following advantages: regular shape, compact and dense structure, good settling performance, high biomass, multiple microbial functions, less residual sludge, and strong tolerance to biotoxins and organic load fluctuations. It has become one of the most promising biological wastewater treatment technologies.

[0005] Currently, aerobic granular sludge technology is rarely used in wastewater treatment plants, and research on granulation selection based on activated sludge is mostly limited to SBR processes, making it difficult to integrate into existing continuous flow activated sludge infrastructures. Therefore, some studies have considered directly incorporating the granulation process into the wastewater treatment process, such as sending wastewater into a cyclone separator to separate and aggregate sludge into granules using centrifugal force, which is then returned to the wastewater treatment tank for recycling. However, the aforementioned cyclone separators often fail to treat wastewater to meet sludge granulation requirements, instead concentrating sludge. Furthermore, the process is susceptible to factors such as unstable wastewater composition (concentration), leading to a higher probability of clogging and overload, resulting in a higher failure rate and more complex maintenance after damage. Therefore, this application proposes a new technical solution. Summary of the Invention

[0006] To reduce the impact of unstable wastewater composition on sludge granulation, this application provides a sludge granulation process and system for the main flow zone of a wastewater treatment plant.

[0007] Firstly, this application provides a sludge granulation process for the main flow zone of a wastewater treatment plant, employing the following technical solution:

[0008] A sludge granulation process for the main area of ​​a wastewater treatment plant includes:

[0009] S1. Sludge is drawn out from the main sedimentation tank by the sludge discharge mechanism and temporarily stored in the sludge tank.

[0010] S2. Sludge is taken from the sludge tank by the pre-sludge circulation mechanism and sent to the stabilization tank. Water is taken from the drainage area of ​​the main tank by the water circulation pipeline.

[0011] S3. A composite screw feeder with at least one mixing section takes sludge from the stabilization tank, and water is taken from above the sludge in the stabilization tank through a set post-water distribution pipeline and sent into the mixing section of the composite screw feeder for mixing.

[0012] S4. The set cyclone module receives the mixture leaving the composite screw feeder and performs sludge thickening and screening.

[0013] S5. The sludge generated in S4 is taken out and divided into a granulation group and a recycling group; the sludge in the granulation group is added and re-proportioned to form granules; the sludge in the recycling group is transported to the main stream tank for a new round of sedimentation by a set backflow dispersing mechanism.

[0014] Optionally, S4 further includes:

[0015] The discharge port of the compound screw feeder is connected to a preset buffer tank via a pipe;

[0016] The mixture is drawn from the buffer tank by a pump and fed into the cyclone module;

[0017] The buffer tank has an upward-extending central pipe at its bottom, which connects the discharge port of the composite screw feeder to the lower end of the central pipe.

[0018] Secondly, this application provides a system for sludge granulation in the main flow zone of a wastewater treatment plant as described above, employing the following technical solution:

[0019] A system for use in the sludge granulation process of the main flow zone of a wastewater treatment plant as described above, comprising:

[0020] It includes a sludge discharge mechanism, a sludge tank, a water circulation pipeline, a pre-sludge circulation mechanism, a stabilization and proportioning tank, a post-water distribution pipeline, a post-sludge circulation mechanism, and a vortex module;

[0021] The post-sludge recycling mechanism includes a composite screw feeder with at least one section being a mixing section. The input port of the composite screw feeder is connected to the stabilization tank and the output port is connected to the feed inlet of the vortex module. The post-water distribution pipeline is connected to the mixing section of the composite screw feeder.

[0022] Optionally, the composite screw feeder includes a cylindrical outer shell, a rotating shaft, staggered blades, helical blades, and a motor. The outer shell is provided with an inlet port and an outlet port, and the inlet port is connected to the lower part of the stable proportioning tank. The rotating shaft is coaxially disposed in the outer shell and rotatably connected. The motor is located outside the outer shell and connected to the rotating shaft. There are multiple helical blades and they are coaxially fixed outside the rotating shaft. Staggered blades are distributed between two adjacent helical blades.

[0023] The outer shell is broken between two adjacent spiral blades and a water supply ring is fitted at the broken end. An integrated sleeve is provided inside the water supply ring. The integrated sleeve is fitted onto the rotating shaft. The rotating shaft is located inside the integrated sleeve and has a section with a smaller diameter than other parts, which is separated from the integrated sleeve to form a transmission chamber.

[0024] The outer wall of the integrated sleeve is radially fixed with several support pillars, and the other end of the support pillars is fixed to the inner wall of the water supply ring.

[0025] The integrated sleeve is fitted with an outer sealing ring, the length of which is greater than that of the integrated sleeve and the ring opening contacts the rotating shaft. The misaligned blade penetrates the outer sealing ring and one end of which is inserted into the integrated sleeve. The integrated sleeve is equipped with a reciprocating swing mechanism of the linkage rotating shaft and the misaligned blade. The misaligned blade swings back and forth around the center of the rotating shaft and the integrated sleeve has a slot for the misaligned blade to move.

[0026] The support column penetrates the outer sealing ring, and the outer sealing ring has a slot for the support column to move. The area where the outer sealing ring is located is the mixing section of the composite screw feeder and is connected to the water supply pipeline. The inner wall of the outer sealing ring is provided with a water outlet unit.

[0027] Optionally, the water outlet unit includes a movable block and a pneumatic telescopic unit. The movable block is slidably connected to the water supply ring and the sliding direction is radial to the water supply ring. A water outlet channel is provided inside the movable block. The water outlet channel is Y-shaped and one port is on the side of the movable block facing the rotating shaft, while the other two ports are located on the side of the movable block and close to the side away from the rotating shaft.

[0028] The pneumatic telescopic unit is located on the side of the movable block away from the rotating shaft and the telescopic end is fixed to the movable block. One water outlet unit corresponds to one misaligned blade. Two misaligned blades are grouped together. Two pneumatic telescopic units that match the same group of misaligned blades are connected to each other. A pressure block is fixed at the end of the misaligned blade away from the rotating shaft. The movement path of the pressure block is intersected with that of the movable block. The ends of the pressure block and / or the movable block are rounded.

[0029] The movable block occupies a span of angle a in the circumferential direction of the water supply ring. When one pressure block of the same set of misaligned blades presses on the movable block and is aligned, the other pressure block is a span of angle a+b from the corresponding pressure block. Here, a and b are preset values, and b is a transition value used to prevent two pressure blocks of the same set from pressing the movable block at the same time.

[0030] A water cavity is provided inside the water supply ring. After the movable block passes through the water cavity and one movable block is pressed down by the pressure block, the other movable block in the same group pops out toward the rotating shaft and the side port is connected to the water cavity.

[0031] Optionally, the reciprocating rocking mechanism includes a frame, an eccentric wheel, and movable rods. The eccentric wheel is eccentrically fixed to the rotating shaft. The frame is sleeved around the eccentric wheel and parallel to it. Two symmetrical inner walls of the frame contact the eccentric wheel, and guide rods are fixed to the corresponding outer surfaces of the two inner walls. Guide sleeves are fitted on the guide rods, and the end of the guide sleeve away from the frame is fixed to the inner wall of the integrated sleeve. The number of movable rods is the same as the number of misaligned blades and corresponds one-to-one. One end of the movable rod is hinged to the frame, and the other end is axially slidably connected to the misaligned blades. There are multiple movable rods distributed on both sides of the line connecting the two guide rods.

[0032] Optionally, the post-sludge recycling mechanism further includes a pump, the output port of which is connected to the feed inlet of the cyclone module, and the input port is connected to the composite screw feeder.

[0033] Optionally, the post-sludge recycling mechanism further includes a buffer tank, with a central pipe extending from the bottom of the buffer tank, the lower end of which is connected to the discharge port of the composite screw feeder; the input port of the pump is connected to the bottom of the buffer tank.

[0034] Optionally, a controller is also included, which is electrically connected to the pump, the compound screw feeder, and the downstream water distribution pipeline. The controller is configured as follows:

[0035] Obtain local 24-hour electricity price distribution data and define low-price periods according to user instructions;

[0036] If the current time is a low electricity price period, send high-flow granulation prompts and / or fluid concentration prompts to pre-recorded users.

[0037] Optionally, the downstream water supply pipeline includes a second water pump and a third pipe installed at the input and output ports of the second water pump. A flexible hose is installed at the outer end of the third pipe connected to the input port of the second water pump, and a floating plate is fixed at the other end of the flexible hose. The floating plate floats on the water surface in the stable proportioning tank, and the opening of the flexible hose is located below the floating plate. The third pipe connected to the output port of the second water pump is connected to the mixing section of the composite screw feeder.

[0038] Secondly, this application provides a sludge granulation process for the main flow zone of a wastewater treatment plant, employing the following technical solution:

[0039] A sludge granulation process for the main flow zone of a wastewater treatment plant, which utilizes the sludge granulation system for the main flow zone of a wastewater treatment plant as described in any of the above-mentioned methods to utilize the water and sludge overflowing after aeration and sedimentation.

[0040] In summary, this application has the following beneficial technical effects: it can make the composition of wastewater (containing sludge) fed into the cyclone module relatively stable, thereby reducing the probability of clogging and the abrasion rate, thus reducing the failure rate and maintenance work;

[0041] On the other hand, relatively "pure" concentrated sludge is prepared using the cyclone module. Some of the concentrated sludge can be more conveniently used in conjunction with a sludge granulator for sludge granulation. On the other hand, it can be directly reused to provide concentrated sludge for the main tank. This has at least two advantages: first, it improves the settling properties of the sludge in the main tank and accelerates the sedimentation process; second, it utilizes the high proportion of microbial communities in the concentrated sludge to improve the biochemical activity of the main tank and enhance the settling properties of the sludge in the main tank; moreover, after multiple cycles of screening, it is beneficial to accelerate sludge granulation. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the system composition of this application;

[0043] Figure 2 This is a partial structural schematic diagram of the composite screw feeder of this application;

[0044] Figure 3 This is a partial sectional view of the composite screw feeder of this application;

[0045] Figure 4 This is a schematic diagram of the control structure of the controller in this application.

[0046] Explanation of reference numerals in the attached drawings: 1. Sludge discharge mechanism; 11. Sludge pump; 12. Pipeline 1; 2. Sludge tank; 3. Water circulation pipeline; 31. Water pump 1; 32. Pipeline 2; 4. Pre-sludge circulation mechanism; 41. Screw feeder; 5. Stabilizing proportioning tank; 6. Post-water distribution pipeline; 61. Water pump 2; 62. Pipeline 3; 63. Hose; 64. Floating plate; 7. Post-sludge circulation mechanism; 71. Composite screw feeder; 711. Housing; 712. Rotating shaft; 713. Offset blades; 7131. Press block; 714. Screw 715. Rotary blades; 716. Motor; 717. Water supply ring; 718. Integrated sleeve; 719. Support column; 710. Outer sealing ring; 72. Water outlet unit; 721. Movable block; 722. Pneumatic telescopic unit; 73. Frame; 731. Guide rod; 732. Guide sleeve; 74. Eccentric wheel; 75. Movable rod; 76. Pump; 77. Buffer tank; 771. Central pipe; 8. Swirl module; 9. Backflow dispersing mechanism; 91. Connector pipe; 92. Drive shaft; 93. Conical cover; 94. Stirring blades; 95. Dispersing blades. Detailed Implementation

[0047] The following is in conjunction with the appendix Figures 1-4 This application will be described in further detail.

[0048] This application discloses a sludge granulation process for the main flow zone of a wastewater treatment plant.

[0049] Reference Figure 1 The mainstream sludge granulation process in wastewater treatment plants includes the following steps:

[0050] S1. Sludge is drawn out from the main sedimentation tank by the sludge discharge mechanism 1 and temporarily stored in the sludge tank 2.

[0051] Understandably, this process is based on the mainstream layout of wastewater treatment plants and is used in conjunction with the sludge process. It requires a sedimentation stage after aeration to reuse part of the sludge formed during sedimentation. At the same time, it is understandable that during the activated sludge granulation process, staff can actively add other raw materials as needed. These raw materials include fly ash powder, microbial inoculum blocks / granules, etc. The specific proportions can be determined by each wastewater treatment plant according to its needs. This part serves as an auxiliary material, and the reused activated sludge contains a large number of polyphosphate-accumulating bacteria.

[0052] It should be noted that, in order to make the process appear more coherent, the various mechanisms and facilities in the process are specifically described in the embodiments of the system in this application, and will not be repeated here.

[0053] In this embodiment, the main stream tank is an integrated aeration and sedimentation tank. After aeration is completed by the aeration equipment, the tank enters the sedimentation stage. After the sludge settles, the upper clarified liquid overflows through the overflow pipe and is sent out. The sludge discharge mechanism 1 extracts the sludge after sedimentation.

[0054] S2. Sludge is taken from sludge tank 2 by the pre-sludge circulation mechanism 4 and sent to the stable proportioning tank 5, and water is taken from the drainage area of ​​the main stream tank by the water circulation pipeline 3.

[0055] As can be seen from the above, in order to reduce the impact of unstable wastewater composition, this process will actively use the stabilization tank 5 to actively adjust the sludge composition to ensure consistent water content, thus laying the foundation for subsequent steps.

[0056] S3. The composite screw feeder 71, which has at least one mixing section, takes sludge from the stabilization tank 5, and uses the provided post-water distribution pipeline 6 to take water from above the sludge in the stabilization tank 5 and send it into the mixing section of the composite screw feeder 71 for mixing.

[0057] Based on the above settings, this application will not directly carry out stirring and mixing in the stable proportioning tank 5, firstly because a mixture with low fluidity and low consistency will cause the screw feeding mechanism to fail, and using other special pumps is more expensive and increases the probability of failure.

[0058] Secondly, the large amount of sludge and water in the stable proportioning tank 5 makes mixing difficult and energy-intensive. Moreover, the relatively large sludge particles at this point are prone to rapid stratification and require continuous mixing.

[0059] After the application is approved, the water supply pipeline 6, together with the improved composite screw feeder 71, can simultaneously complete the mixing of the new formula ratio during the low-cost conveying process, which is more cost-effective and more stable in operation, and can relatively avoid the above-mentioned problems.

[0060] S4. The set cyclone module 8 receives the mixture leaving the composite screw feeder 71 and performs sludge thickening and screening.

[0061] In this embodiment, the cyclone module 8 can be a hydrocyclone, which is existing technology. The following example illustrates this: the upper part of the cyclone module 8 is cylindrical, and the lower part is an inverted cone, with the cone tip serving as the discharge port. After sludge is concentrated and large clumps of impurities are removed, it exits from the discharge port and is then pumped back for reuse via additional pipes and pumps. A feed inlet is installed on the upper sidewall of the cyclone module 8, allowing tangential feeding. A pipe is located at the center of the upper part of the cyclone module 8, extending upwards to form an overflow pipe. After the high-speed fluid enters, it spirals along the inner wall. Under centrifugal force, the sludge clumps together and concentrates, gradually moving downwards and exiting from the discharge port, while lighter impurities are discharged through the overflow pipe.

[0062] S5. The sludge generated in S4 is taken and divided into a granulation group and a recycling group, that is, it is divided into two parts. The ratio of the two parts can be determined according to the scale of the main pool in the plant area and the raw material requirements for sludge granulation, such as 3:1.

[0063] The sludge in the granulation group is dewatered (by sun-drying and dewatering machine), the components are added and re-proportioned, and then granulated (by being fed into a sludge granulator) to form granules; while the recirculation group is transported to the main stream tank for a new round of sedimentation by the set backflow dispersing mechanism 9.

[0064] Based on the above settings, this application can make the composition of wastewater (including sludge) fed into the cyclone module relatively stable, which reduces the probability of clogging on the one hand and the erosion rate on the other, thereby reducing the failure rate and reducing maintenance work;

[0065] On the other hand, relatively "pure" concentrated sludge is prepared using the cyclone module. Some of the concentrated sludge can be more conveniently used in conjunction with a sludge granulator for sludge granulation. On the other hand, it can be directly reused to provide concentrated sludge for the main tank. This has at least two advantages: first, it improves the settling properties of the sludge in the main tank and accelerates the sedimentation process; second, it utilizes the high proportion of microbial communities in the concentrated sludge to improve the biochemical activity of the main tank and enhance the settling properties of the sludge in the main tank; moreover, after multiple cycles of screening, it is beneficial to accelerate sludge granulation.

[0066] In another embodiment of this process, the discharge port of the composite screw feeder 71 is connected to a preset buffer tank 77 via a pipe.

[0067] Pump 76 draws the mixture from buffer tank 77 and feeds it into cyclone module 8; wherein, the bottom of buffer tank 77 is provided with an upwardly extending central pipe 771 and the discharge port of composite screw feeder 71 is connected to the lower end of central pipe 771.

[0068] The advantages of the above settings are:

[0069] 1) The pump 76 is designed to allow users to actively pressurize the fluid, which can better cooperate with the cyclone module 8 for sludge separation and granulation. On the other hand, it can cooperate with the composite screw feeder 71 to complete the feeding, preventing feeding difficulties caused by large climbing heights from causing too much obstruction to the normal use of this application.

[0070] 2) The buffer tank 77 can be used to reduce the load impact caused by the uncoordinated flow of the composite screw feeder 71 after the adjustment of the pump 76 and the flow fluctuation, thereby improving the stability of equipment operation. At the same time, due to the structural settings such as the central pipe 771, the fluid has a falling impact mixing process in the buffer tank 77, which can reduce the impact of the unstable unit fluid composition caused by fluid stratification during the feeding process on the subsequent cyclone granulation.

[0071] This application discloses a system for sludge granulation process in the main zone of the aforementioned wastewater treatment plant.

[0072] Reference Figure 1 The system applied to the sludge granulation process in the mainstream area of ​​the above-mentioned wastewater treatment plant includes a sludge discharge mechanism 1, a sludge tank 2, a water circulation pipeline 3, a pre-sludge circulation mechanism 4, a stabilization and proportioning tank 5, a post-water distribution pipeline 6, a post-sludge circulation mechanism 7, and a swirl module 8.

[0073] The sludge discharge mechanism 1 includes a sludge pump 11 and a pipe 12 installed at the input and output ports of the sludge pump 11. The pipe 12 forms an intake port and a discharge port. The intake port is connected to the main stream tank responsible for sedimentation, and the discharge port is connected to the sludge tank 2.

[0074] In another embodiment, the sludge discharge mechanism 1 can be a screw feeder with its discharge port suspended in the air. A screening device (such as a funnel with a built-in screen) is added below it. The screen is used to remove fibrous impurities and large inorganic particles from the sludge, preventing clogging in subsequent processing. In addition to including a 60-mesh screen, the screening device can also be equipped with an automatic sludge cleaner (suction device, gripping robot, etc.) and a pressure sensor for the screen. This sensor is set to activate the sludge cleaner when the pressure difference reaches a set value, thus cleaning the impurities from the screen.

[0075] In this embodiment, the main stream tank is an integrated aeration and sedimentation tank. After aeration is completed by the aeration equipment, the tank enters the sedimentation stage. After the sludge settles, the upper clarified liquid overflows through the overflow pipe and is sent out. The sludge discharge mechanism 1 extracts the sludge after sedimentation.

[0076] Sludge tank 2 is located next to the main tank (i.e., the integrated aeration and sedimentation tank). Sludge tank 2 has an open structure and the top opening can be fitted with a suitable top cover, which can provide a shielding and sealing effect when necessary. Part of the sludge entering sludge tank 2 is used in this application, while the rest can be disposed of harmlessly by relevant personnel and units, such as through landfill.

[0077] The water circulation pipeline 3 includes a water pump 31 and a second pipeline 32 connecting the input and output ports of the water pump 31. A filter head is installed at the external port of the second pipeline 32, which connects to the input port, and is then placed in the overflow area of ​​the main flow tank. It should be noted that the external port of the second pipeline 32, which connects to the output port of the water pump 31, extends into the stabilization tank 5, located above the sludge and facing the inner wall of the tank.

[0078] The pre-treatment sludge recycling mechanism 4 includes a screw feeder 41. The sludge inlet of the screw feeder 41 is connected to the lower side wall or bottom of the sludge tank 2 via a pipe, and the sludge outlet of the screw feeder 41 is connected to the bottom of the stabilization tank 5 via a pipe. The stabilization tank 5 can be an open concrete structure or a tank structure with a pressure relief valve.

[0079] Operating procedure: First, the staff feeds a certain volume of sludge into the stabilization tank 5. Assuming the sludge feed amount is v1, then: according to v2 / v1=a1 / a2, calculate v2, where v2 is the minimum amount of water that should be fed in; a1 / a2 is the low clogging probability ratio value that the staff has tested in advance according to the specifications of the cyclone module 8 (such as: hydrocyclone, which is existing technology), which is a manually set parameter; then, according to v2, control the water pump 31 to feed water into the stabilization tank 5.

[0080] It should be noted that the reason why the water circulation pipeline 3 or the water pump 31 does not directly supply water to the post-sludge circulation mechanism 7 is that even though multiple mainstream pools can operate alternately during the sewage treatment process, it is not always possible that a mainstream pool is in the sedimentation stage when water is needed. Therefore, the water is first sent to the stable proportioning pool 5, which also makes it easier to determine the proportion.

[0081] Regarding the calculation of sludge volume: This can be calculated based on the feeding speed and feeding time of the screw feeder 41. Regarding the calculation of water volume in the stabilization tank 5: Install a level gauge to measure the water level, calculate the total volume using the volume formula based on the inner bottom area of ​​the stabilization tank 5, and then subtract the sludge volume.

[0082] The post-sludge recycling mechanism 7 includes a composite screw feeder 71 with at least one section being a mixing section. In this embodiment, one section is used as an example for explanation. The input port of the composite screw feeder 71 is connected to the bottom side wall of the stabilization tank 5 through a pipe, and the output port is connected to the feed inlet of the vortex module 8.

[0083] It is understandable that electrically controlled valves can be installed on the aforementioned pipeline structures to achieve safety shut-off and other effects.

[0084] The downstream water distribution pipeline 6 includes a second water pump 61 and a third pipe 62 installed at the input and output ports of the second water pump 61. A flexible hose 63 is installed at the outer end of the third pipe 62, which connects to the input port of the second water pump 61. A floating plate 64, which can be a wooden board, is fixed to the other end of the flexible hose 63. The floating plate 64 floats on the water surface in the stabilization tank 5, and the opening of the flexible hose 63 is located below the floating plate 64. The third pipe 62, which connects to the output port of the second water pump 61, connects to the mixing section of the composite screw feeder 71.

[0085] When it is necessary to prepare activated sludge, the composite screw feeder 71 is used to extract sludge from the stabilization tank 5, and the water pump 61 is used to extract water from the stabilization tank 5. The ratio of the sludge extraction rate to the water extraction rate is kept as close as possible to the sludge-to-water ratio in the stabilization tank 5. At this time, the composite screw feeder 71 mixes the sludge and water while conveying the mixture to the cyclone module 8. Then, the cyclone module 8 separates and concentrates the sludge, and then sends it out through the discharge port and back to the sewage treatment facility for reuse through pipelines.

[0086] In this embodiment, an example of the cause of the malfunction due to unstable wastewater composition is:

[0087] 1) Small clumps and lumps of sludge are small in mass and have poor separation effect under centrifugal force in the cyclone module 8. Therefore, it is not recommended to use the incoming sewage directly. Aerated sewage can be selected. However, the composition of the original sewage (mainly turbidity in this embodiment) is unstable, which leads to relatively unstable sludge ratio and other properties formed by agglomeration after aeration. If the cyclone module 8 is too small, it is easy to clog; if the size is too large, the energy consumption will be high, since the equipment mainly relies on the pressure difference between the inlet and outlet to work.

[0088] 2) Wastewater carrying sand and gravel forms a high-speed fluid after entering the cyclone module 8. During use, the fluid continuously erodes the inner wall of the equipment. If the wastewater composition is unstable, the inlet and outlet pressure difference of the equipment can only be as large as possible in order to improve the separation effect. However, this results in high energy consumption and more severe erosion of the inner wall.

[0089] As can be seen from the foregoing, the application documents allow staff to stabilize the wastewater composition by actively mixing the swirl module 8 in advance, making the swirl module 8 more compatible with the wastewater. This reduces the probability of clogging and also reduces energy consumption and erosion of the inner wall.

[0090] It should be noted that the reason why this application does not directly mix and transport the sludge to the cyclone module 8 after mixing in the stabilization tank 5 is because the amount of sludge and water in the stabilization tank 5 is large, making mixing difficult and energy-intensive. Moreover, because the sludge particles are relatively large at this time, they are prone to rapid stratification and require continuous mixing. The application document sets the mixing process to occur simultaneously during the feeding process, which can relatively avoid the above problems.

[0091] Reference Figure 2 In one embodiment of this application, the composite screw feeder 71 includes a housing 711, a rotating shaft 712, staggered blades 713, a screw blade 714, and a motor 715.

[0092] The outer shell 711 is columnar, closed at both ends, with one end having a side-fixed flange pipe joint as an inlet and the other end having a side-fixed flange pipe joint as an outlet; the inlet of the outer shell 711 is connected to the lower part of the stabilization tank 5 through a pipe so as to extract sludge.

[0093] The rotating shaft 712 is coaxially mounted in the housing 711 and rotatably connected. The motor 715 is located outside the housing 711. It can be a geared motor and its output shaft is fixed to one end of the rotating shaft 712. The spiral blade 714 is fixedly mounted around the rotating shaft 712.

[0094] In this embodiment, there are multiple helical blades 714 distributed axially. Taking two helical blades 714 as an example: the two helical blades 714 are axially separated, and the misaligned blade 713 is located between the two helical blades 714.

[0095] Reference Figure 3 The outer shell 711 is broken at the position between two adjacent spiral blades 714, and a water supply ring 716 is sleeved and fixed at the broken end, that is, the two sections of the outer shell 711 are connected into one by the water supply ring 716.

[0096] An integrated sleeve 717 is provided on the inner side of the water supply ring 716. The integrated sleeve 717 is sleeved outside the rotating shaft 712. The rotating shaft 712 is located inside the integrated sleeve 717 and has a section with a smaller diameter than other parts. It is separated from the integrated sleeve 717 to form an inner transmission chamber.

[0097] Several support pillars 718 are radially fixed to the outer wall of the integrated sleeve 717. The other end of each support pillar 718 is fixed to the inner wall of the water supply ring 716, meaning the integrated sleeve 717 cannot rotate, while the rotating shaft 712 rotates relative to it. An outer sealing ring 719 is fitted onto the integrated sleeve 717. The length of the outer sealing ring 719 is greater than that of the integrated sleeve 717, and its opening contacts the rotating shaft 712. The misaligned blade 713 penetrates the outer sealing ring 719 and extends into the inner transmission chamber. A reciprocating swing mechanism consisting of the linkage rotating shaft 712 and the misaligned blade 713 is installed inside the integrated sleeve 717.

[0098] The misaligned blade 713 oscillates back and forth around the rotating shaft 712, and the integrated sleeve 717 has a slot for the misaligned blade 713 to move; the support column 718 penetrates the outer sealing ring 719, and the outer sealing ring 719 has a slot for the support column 718 to move. The area where the outer sealing ring 719 is located is the mixing section of the composite screw feeder 71 and is connected to the rear water supply pipe 6. The inner wall of the outer sealing ring 719 is provided with a water outlet unit 72.

[0099] According to the above settings, after the rotating shaft 712 rotates, the spiral blades 714 pump the sludge. After the sludge moves to the water supply ring 716 for a period of time, the water distribution pipe 6 adds water to the sludge through the water outlet unit 72. The staggered blades 713 continuously swing back and forth to stir and form fluid.

[0100] It should be noted that spiral conveying of fluids is generally not suitable, but in this embodiment, the first half of the composite spiral feeder 71 continuously pushes sludge over, so it can be used in conjunction with the spiral blades 714 in the second half to convey the mixed fluid.

[0101] It is understandable that the stirring section corresponding to the water supply ring 716 can be multiple sections, which can be selected according to actual needs. The longer the rotating shaft 712 is, the more stirring sections there are. The number of misaligned blades 713 can also be increased according to needs.

[0102] The water outlet unit 72 includes a movable block 721 and a pneumatic telescopic unit 722. The movable block 721 is slidably connected to the water supply ring 716 and the sliding direction is radial to the water supply ring 716. A water outlet channel is provided in the movable block 721. The water outlet channel is Y-shaped and one port is on the side of the movable block 721 facing the rotating shaft 712. The other two ports are located on the side of the movable block 721 and close to the side away from the rotating shaft 712.

[0103] The pneumatic telescopic unit 722 is located on the side of the movable block 721 away from the rotating shaft 712. The pneumatic telescopic unit 722 includes a cylinder embedded in the water supply ring 716, a piston axially slidably connected in the cylinder, and a piston rod fixed to the piston. The piston rod extends out of the cylinder and its end is fixed to the movable block 721. The end of the cylinder away from the movable block 721 has an external opening.

[0104] One water outlet unit 72 corresponds to one misaligned blade 713. Two misaligned blades 713 are grouped together, and the pneumatic telescopic units 722 of the water outlet units 72 that match the same group of misaligned blades 713 are interconnected. A pressure block 7131 is fixed to the end of the misaligned blade 713 away from the rotating shaft 712. The moving path of the pressure block 7131 and the movable block 721 are intersected. The ends of the pressure block 7131 and / or the movable block 721 are rounded.

[0105] The movable block 721 occupies a span of angle 'a' in the circumferential direction of the water supply ring 716. When one pressure block 7131 of the same set of misaligned blades 713 presses on the movable block 721 and is centered (i.e., center-aligned), the other pressure block 7131 is a span of angle 'a+b' from the corresponding pressure block 7131. Here, 'a' and 'b' are preset values, and 'b' is a transition value used to prevent two pressure blocks 7131 of the same set from simultaneously pressing on the corresponding pressure block 7131. Example: 'a' is 15°, and 'b' is 3°.

[0106] The water supply ring 716 has a water cavity inside and an inlet hole on the outer wall that connects to the water cavity. The movable block 721 passes through the water cavity and one movable block 721 is pressed down by the pressure block 7131. Then, the other movable block 721 in the same group pops out toward the rotating shaft 712 and the side port connects to the water cavity.

[0107] According to the above settings, when the misaligned blade 713 swings, the pressure block 7131 at the end of one misaligned blade 713 presses down the movable block 721, and the other movable block 721 in the same group connects to the water chamber and starts to discharge water; when the misaligned blade 713 continues to swing, the two movable blocks 721 in the same group alternately discharge water.

[0108] The reason for using the above-mentioned water outlet unit 72 and pneumatic telescopic unit 722 in this application, instead of using springs or other means to allow the movable block 721 to automatically reset, is that the misaligned blade 713 continuously swings and repeatedly drives the pressure block 7131 to apply pressure and release to the movable block 721. Moreover, the springs here are small springs, which are prone to fatigue, elastic decay, deformation, etc., affecting the water output. Pneumatics are relatively stable, but if each pneumatic telescopic unit 722 is equipped with a pump, the cost-effectiveness is not high and the equipment is complex and the failure rate increases. Therefore, the above-mentioned interconnected water outlet unit 72 and pneumatic telescopic unit 722 are used, with paired structures alternately circulating gas, which can achieve the pneumatic effect and eliminate the cumbersome pumping of air.

[0109] The alternating water discharge of the aforementioned movable blocks 721 in the same group requires the reciprocating oscillation of the staggered blades 713. The oscillation of the staggered blades 713 requires the transmission of a reciprocating swing mechanism. In one embodiment of this application, the reciprocating swing mechanism includes a frame 73, an eccentric wheel 74, and a movable rod 75.

[0110] The eccentric wheel 74 is eccentrically fixed to the rotating shaft 712. The eccentric wheel 74 can be a round wheel or a triangular wheel with rounded corners. Taking a triangular wheel as an example, the rotating shaft 712 is fixed at one corner. The frame 73 is sleeved on the outside of the eccentric wheel 74 and is parallel to the eccentric wheel 74. The left and right inner walls of the frame 73 contact the eccentric wheel 74, while the upper and lower inner walls do not. Guide rods 731 are fixed on the symmetrical sides of the frame 73. Guide sleeves 732 are sleeved on the guide rods 731. The end of the guide sleeve 732 away from the frame 73 is fixed to the inner wall of the integrated sleeve 717. The number of movable rods 75 is the same as the number of misaligned blades 713 and they correspond one-to-one. One end of the movable rod 75 is hinged to the frame 73, and the other end is axially slidably connected to the misaligned blade 713, such as by sleeve. The line connecting the connection points of the two movable rods 75 and the line connecting the two guide rods 731 intersect and form an angle, that is, they are distributed on the top, bottom, left, and right sides of the frame 73.

[0111] Working process: The rotation of the rotating shaft 712 drives the eccentric wheel 74 to rotate. After the eccentric wheel 74 rotates, it pushes the frame 73 to move left and right. The left and right movement of the frame 73 pulls the movable rod 75 to move left and right. When the movable rod 75 moves left and right, it slides relative to the misaligned blade 713 and causes it to swing.

[0112] It is understandable that the above is a set of misaligned blades 713. If there are multiple sets of misaligned blades 713, the reciprocating swing mechanism can be multiple and distributed along the axis of rotation 712, or more movable rods 75 can be connected to the frame 73 to connect more misaligned blades 713.

[0113] In this embodiment, the main body of the misaligned blade 713 can be cylindrical or spiral-shaped, etc.

[0114] In another embodiment of this application, the fluid discharged from the composite screw feeder 71 does not directly enter the cyclone module 8. The post-sludge circulation mechanism 7 also includes a pump 76. The output port of the pump 76 is connected to the feed port of the cyclone module 8 through a pipe, and the input port is connected to the composite screw feeder 71. The pump 76 can be a plunger pump, centrifugal pump, etc.

[0115] The pump 76 allows users to pressurize the fluid, better cooperating with the cyclone module 8 for sludge separation and granulation. On the other hand, it works with the composite screw feeder 71 to complete the feeding, preventing feeding difficulties caused by large climbing heights from causing too much obstruction to the normal use of this application.

[0116] In another embodiment of this application, the post-sludge recycling mechanism 7 further includes a buffer tank 77, which has an opening at the top and a suitable top cover hinged to the opening, and the top cover is equipped with a pressure relief valve. The bottom has a central pipe 771 extending out of the bottom of the tank, and the lower end of the central pipe 771 is connected to the discharge port of the composite screw feeder 71 through a pipe. The input port of the pump 76 is connected to the bottom of the buffer tank 77 through a pipe. The buffer tank 77 can be suspended by a base.

[0117] The buffer tank 77 can be used to reduce the load impact caused by the incoordination of the flow of the composite screw feeder 71 after the adjustment of the pump 76 and the flow fluctuation, thereby improving the stability of equipment operation. At the same time, due to the structural settings such as the central pipe 771, the fluid in the buffer tank 77 has a falling impact mixing behavior, which can reduce the impact of fluid composition instability caused by fluid stratification on subsequent granulation.

[0118] Reference Figure 4 In another embodiment of this application, the application further includes a controller electrically connected to the pump 76, the compound screw feeder 71, the water circulation pipeline 3 (water pump 31), the pre-sludge circulation mechanism 4 (screw feeder 41), and the post-water distribution pipeline 6 (water pump 61), and the controller is configured as follows:

[0119] Obtain local 24-hour electricity price distribution data and define low-price periods according to user instructions;

[0120] If the current time is a low electricity price period, send high-flow granulation prompts and / or fluid concentration prompts to pre-recorded users.

[0121] Understandably, 24-hour electricity price distribution data, i.e., local peak and off-peak electricity prices and time period information, can be obtained through online searches or pre-stored by staff. If the user defines off-peak electricity as a low-price period, then the corresponding time period for off-peak electricity is the low-price period. An example of how the above-mentioned notification information is sent: the controller is connected to the internet and to a designated cloud platform. The user registers a corresponding account on the cloud platform, and the information is sent to the individual account through the cloud platform. Besides online transmission, this information can also be sent via SMS.

[0122] According to the above settings, the staff can operate the controller at appropriate times to adjust other electrical equipment of this application to increase the flow rate into the cyclone module 8 and increase the concentration of the fluid. The reason for this setting is that increasing the flow rate and increasing the concentration will increase the pressure difference required by the cyclone module 8, which will result in greater energy consumption for pressurizing the feeding pump 76. It is more cost-effective to carry out sludge thickening and granulation during periods of low electricity price.

[0123] Reference Figure 1In another embodiment of this application, the height of the liquid outlet port of the swirl module 8 should be greater than that of the main stream pool, or the swirl module 8 is installed on a raised platform on the side of the main stream pool; at this time, the countercurrent dispersing mechanism 9 includes a connector pipe 91, a drive shaft 92, a conical cover 93, a stirring blade 94, and a dispersing blade 95.

[0124] Its connector pipe 91 is connected to one port of a three-way pipe structure to the output port of the cyclone module 8. The connector pipe 91 is vertically fixed to the top of the main stream pool by a bracket, and the lower end is fixed to a conical cover 93. The drive shaft 92 is rotatably connected to a preset crossbeam in the connector pipe 91 and is vertical. The upper end of the drive shaft 92 extends into the connector pipe 91 and multiple stirring blades 94 are fixed to the outer wall. The lower end of the drive shaft 92 extends into the conical cover 93 and multiple dispersing blades 95 are fixed to the outer wall.

[0125] A belt drive device is installed on the side of the connector tube 91 on the bracket, and the belt passes through the connector tube 91 and is fitted with a pulley pre-fixed to the drive shaft 92.

[0126] When in use, when the concentrated sludge is fed into the connector pipe 91, it is first mixed more evenly by the rotating stirring blades 94, and then falls and is dispersed by the rotating dispersing blades 95, so as to prevent the concentrated sludge from falling into the main pool in large clumps and failing to play its required role.

[0127] Understandably, there can be multiple countercurrent dispersing mechanisms 9 above the main flow tank, each connected to the output port of the vortex module 8 via pipes. Therefore, this is no longer a three-way pipe, but a multi-way pipe. This arrangement allows for a more uniform distribution of concentrated sludge in the main flow tank.

[0128] In one embodiment of the application, a sludge screening device is added after the cyclone module 8 (connected to one of the countercurrent dispersing mechanisms 9). Its structure can be similar to the aforementioned screening device, with a screen mesh of 150 mesh, and its working principle is the same as that of the screening device after the screw feeder.

[0129] Before screening, the components (fly ash, diatomaceous earth, etc., >200 mesh) are added manually or by using a feeder or other equipment. Then, screening is carried out. Large sludge particles that do not pass through the screen are removed from the screen to form larger sludge particles. Small sludge particles that pass through the screen are incorporated into the return flow dispersing mechanism 9.

[0130] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A sludge granulation process in the main stream zone of a sewage plant, characterized in that, It comprises the following steps: S1, the sludge discharge mechanism (1) is set to draw sludge from the main flow tank responsible for sedimentation, and the sludge tank (2) is set to temporarily store; S2, the front sludge circulating mechanism (4) is set to take sludge from the sludge tank (2) and send it to the stable proportioning tank (5), and the water circulating pipeline (3) is set to take water from the drainage area of the main flow tank; S3, the composite screw feeder (71) with at least one stirring section takes the sludge in the stable proportioning tank (5), and the rear water distribution pipeline (6) is set to take water from above the sludge in the stable proportioning tank (5) and send it to the stirring section of the composite screw feeder (71) for mixing; S4, the cyclone module (8) is set to receive the mixture from the composite screw feeder (71) and concentrate and screen the sludge; S5, the sludge produced in S4 is taken and divided into a granulation group and a recirculation group; wherein the sludge in the granulation group is added and proportioned to form particles; the recirculation group is transported to the main flow tank for a new round of sedimentation by the backflow dispersing mechanism (9); The S4 further comprises: The discharge port of the composite screw feeder (71) is connected to the pipeline of the pre-set buffer tank (77); The pump (76) is used to extract the mixture from the buffer tank (77) and send it to the cyclone module (8); The bottom of the buffer tank (77) is provided with a middle pipeline (771) that extends upward, and the discharge port of the composite screw feeder (71) is connected to the lower end of the middle pipeline (771); The composite screw feeder (71) comprises a cylindrical shell (711), a shaft (712), staggered blades (713), spiral blades (714) and a motor (715), the shell (711) is provided with an inlet port and an outlet port, the inlet port is connected to the lower part of the stable proportioning tank (5), the shaft (712) is coaxially arranged in the shell (711) and is rotationally connected, the motor (715) is located outside the shell (711) and is connected to the shaft (712), the spiral blades (714) are multiple and are coaxially fixed to the shaft (712) outside, and the staggered blades (713) are arranged between adjacent two spiral blades (714); The shell (711) is disconnected between adjacent two spiral blades (714), and the disconnected end is sleeved with a water supply ring (716), the water supply ring (716) is provided with an integrated sleeve (717) inside, the integrated sleeve (717) is sleeved on the shaft (712), and the shaft (712) has a section inside the integrated sleeve (717) with a smaller diameter than other parts and is separated from the integrated sleeve (717) to form a transmission chamber; The outer wall of the integrated sleeve (717) is fixed with a plurality of struts (718), and the other end of the strut (718) is fixed to the inner wall of the water supply ring (716); The integrated sleeve (717) is sleeved with an outer sealing ring (719), the length of the outer sealing ring (719) is greater than that of the integrated sleeve (717), the ring opening contacts the rotating shaft (712), the staggered blades (713) penetrate the outer sealing ring (719) and one end penetrates the integrated sleeve (717), the integrated sleeve (717) is provided with a reciprocating swing mechanism of the rotating shaft (712) and the staggered blades (713), the staggered blades (713) reciprocate around the center of the rotating shaft (712) and the integrated sleeve (717) is provided with a slot one for the movement of the staggered blades (713); The support (718) penetrates the outer sealing ring (719) and the outer sealing ring (719) is provided with a slot two for the movement of the support (718), the area where the outer sealing ring (719) is located is a stirring section of the composite spiral feeder (71) and is connected with the rear water distribution pipeline (6), and the inner wall of the outer sealing ring (719) is provided with a water outlet unit (72).

2. A system applied to the sludge granulation process in the main stream zone of a sewage plant as claimed in claim 1, characterized by: It comprises a sludge discharge mechanism (1), a sludge pool (2), a water circulation pipeline (3), a front sludge circulation mechanism (4), a stable proportioning pool (5), a rear water distribution pipeline (6), a rear sludge circulation mechanism (7) and a cyclone module (8). The rear sludge circulation mechanism (7) comprises at least one stirring section of a composite spiral feeder (71), the input port of the composite spiral feeder (71) is connected with the stable proportioning pool (5) and the output port is connected with the feed inlet of the cyclone module (8), and the rear water distribution pipeline (6) is connected to the stirring section of the composite spiral feeder (71).

3. The system applied to sludge granulation process in the main stream zone of sewage plant according to claim 2, characterized in that: The water outlet unit (72) comprises a movable block (721) and a pneumatic telescopic unit (722), the movable block (721) is in sliding connection with the water supply ring (716), the sliding direction is the radial direction of the water supply ring (716), the movable block (721) is provided with a water outlet channel, the water outlet channel is Y-shaped, one port is on the side of the movable block (721) facing the rotating shaft (712), and the other two ports are located on the side of the movable block (721) away from the rotating shaft (712); The pneumatic telescopic unit (722) is located on the side of the movable block (721) away from the rotating shaft (712) and the telescopic end is fixed to the movable block (721), one water outlet unit (72) corresponds to one staggered blade (713), the staggered blades (713) are two groups, the two pneumatic telescopic units (722) matching the same group of staggered blades (713) are connected with each other, one end of the staggered blades (713) away from the rotating shaft (712) is fixed with a pressing block (7131), the movement path of the pressing block (7131) and the movable block (721) are staggered, and the end of the pressing block (7131) and / or the movable block (721) is rounded. The movable block (721) occupies a span of a angular value in the circumferential direction of the water supply ring (716), and one pressing block (7131) of the same set of staggered blades (713) is pressed on the movable block (721), and when centered, the other pressing block (7131) is a+b angular value away from the corresponding pressing block (7131), wherein a and b are preset values, and b is a transition value for preventing the two pressing blocks (7131) of the same set from pressing the movable block (721) at the same time; The water cavity is provided in the water supply ring (716), and the movable block (721) passes through the water cavity, and after one movable block (721) is pressed by the pressing block (7131), the other movable block (721) of the same set is ejected towards the rotating shaft (712) and the port on the side is communicated with the water cavity.

4. The system for sludge granulation process in the main stream zone of a sewage plant according to claim 2, characterized in that: The reciprocating swing mechanism includes a frame (73), an eccentric wheel (74) and movable rods (75), the eccentric wheel (74) is eccentrically fixed to the rotating shaft (712), the frame (73) is sleeved outside the eccentric wheel (74) and parallel to the eccentric wheel (74), the two inner walls of the frame (73) symmetrically contact the eccentric wheel (74), and the outer parts of the two inner walls are respectively fixed with guide rods (731), the guide rods (731) are sleeved with guide sleeves (732), and one end of the guide sleeves (732) away from the frame (73) is fixed to the inner wall of the integrated sleeve (717); the number of the movable rods (75) is the same as that of the staggered blades (713) and one-to-one correspondence, one end of the movable rod (75) is hinged to the frame (73), and the other end is axially slidably connected to the staggered blade (713); the movable rods (75) are distributed on both sides of the connecting line of the two guide rods (731).

5. The system for sludge granulation process in the main stream zone of a sewage plant according to claim 2, characterized in that: The rear sludge circulation mechanism (7) further comprises a pump (76), and the output port of the pump (76) is communicated with the inlet of the cyclone module (8), and the input port is communicated with the composite screw feeder (71).

6. The system for sludge granulation process in the main stream zone of a sewage plant according to claim 5, characterized in that: The rear sludge circulation mechanism (7) further comprises a buffer tank (77), and the bottom of the buffer tank (77) has a middle pipeline (771) extending into the tank bottom, and the lower end of the middle pipeline (771) is communicated with the discharge port of the composite screw feeder (71); the input port of the pump (76) is communicated with the bottom of the buffer tank (77).

7. The system for sludge granulation process in the main stream zone of a sewage plant according to claim 5, characterized in that: Further comprising a controller, the controller is electrically connected to the pump (76), the composite screw feeder (71) and the rear water distribution pipeline (6), and the controller is configured to: Obtain local 24-hour electricity price distribution data, and define low electricity price period according to user instruction; If the current time is a low electricity price period, send large flow granulation prompt information and / or increase fluid concentration prompt information to the pre-recorded user.

8. The system for sludge granulation process in the main stream zone of a sewage plant according to claim 7, characterized in that: The rear water distribution pipeline (6) comprises a water pump two (61) and a pipeline three (62) installed at the input and output ports of the water pump two (61), a hose (63) is installed at the external end of the pipeline three (62) communicated with the input port of the water pump two (61), the other end of the hose (63) is fixed with a floating plate (64), the floating plate (64) floats on the water surface in the stable proportioning tank (5) and the nozzle of the hose (63) is below the floating plate (64), the pipeline three (62) communicated with the output port of the water pump two (61) is communicated with the stirring section of the composite spiral feeder (71).

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