Two-stage centrifugal device for efficiently extracting concentrated sludge EPS
Through efficient two-stage centrifugal device and heating treatment, combined with the design of agitating brushes and polytetrafluoroethylene plates, the cell rupture problem during extracellular polymer extraction in wastewater treatment is solved, and efficient and damage-free EPS extraction is achieved. Improves processing efficiency and equipment durability.
Patent Information
- Application Number
- CN202420880751.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-25
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2034-04-25
AI Technical Summary
Existing methods for extracting extracellular polymers can easily lead to rupture of microbial cells, especially during wastewater treatment, where excessive cell rupture is difficult to effectively solve.
A highly efficient two-stage centrifugal device is adopted, which includes a primary centrifuge and a secondary centrifuge. Through centrifugation and heating treatment, the sand particles in the sludge rub against the bacterial pellets, destroying the cross-linking structure of EPS, and combining stirring The design of brushes and PTFE plates prevent cell rupture and secondary centrifuge of the liquid through a self-priming pump to obtain efficiently extracted EPS.
There is no need to add pro-decomposition drugs and sonication, which significantly reduces cell rupture problems, improves sludge treatment efficiency and EPS extraction purity, while extending the service life of the equipment and reducing the friction and bonding of microorganisms to the equipment.
Smart Images
Figure CN222182051U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of wastewater treatment technology, and in particular to a two-stage centrifugal device for efficiently extracting and concentrating sludge EPS. Background Art
[0002] Extracellular polymers (EPS) are some high molecular polymers secreted outside the body by microorganisms, mainly bacteria, under certain environmental conditions. The main components are similar to the intracellular components of microorganisms, mainly high molecular compounds such as polysaccharides and proteins, and are excellent carbon sources for anaerobic fermentation. Extracellular polymers EPS are mainly divided into three parts: (1) Soluble EPS: It has a low degree of binding with cells and can move freely in the environment. (2) Loosely bound EPS: It is located in the outer layer and has a relatively loose structure. It is a mucus layer that can expand into the surrounding environment and has no obvious edges. (3) Tightly bound EPS: It is located in the inner layer, is tightly bound to the cell surface, is stably attached to the outside of the cell wall, and has a certain shape.
[0003] The existing methods for extracting extracellular polymers mainly include adding reagents and resins, ultrasonic treatment or heat treatment, and centrifugation for 3-4 times to extract EPS from different levels of microorganisms in layers. The targets are all relatively clean small amounts of microorganisms or sludge. For example, in the patent with authorization announcement number CN110451762A, PBS buffer, ammonium fluoride, sodium sulfide, sodium dodecyl sulfate, etc. need to be added, and the centrifugal acceleration is as high as 15000g, and multiple centrifugation is performed; for another example, in the patent with authorization announcement number CN105273040A, ultrasonic treatment and formaldehyde treatment are required, and centrifugation is performed.
[0004] However, when using the above method to extract extracellular polymers, the addition of various decomposition-promoting drugs and the ultrasonic treatment process will forcibly strip and extract the microbial tightly bound extracellular polymers (TB-EPS), thereby causing the problem of excessive cell rupture. Utility Model Content
[0005] In order to improve the problem of excessive cell rupture when extracting extracellular polymers in wastewater treatment, the present application provides a two-stage centrifugal device for efficiently extracting concentrated sludge EPS.
[0006] The two-stage centrifugal device for efficiently extracting and concentrating sludge EPS provided in this application adopts the following technical solution:
[0007] A two-stage centrifugal device for efficiently extracting concentrated sludge EPS comprises a frame, a primary centrifuge, a feed pump, a heating box, a secondary centrifuge and a self-priming pump, wherein the primary centrifuge is arranged on the frame and is used to apply centrifugal action to the sludge, the feed pump is arranged on the frame and is used to pump the sludge in the concentrated sludge tank into the primary centrifuge; the heating box is connected to the primary centrifuge and is used to heat the liquid after centrifugation by the primary centrifuge, the secondary centrifuge is connected to the heating box and is used to apply centrifugal action to the heated liquid again, and the self-priming pump is arranged on the frame and is used to pump the liquid in the heating box into the secondary centrifuge.
[0008] By adopting the above technical scheme, the sludge in the concentrated sludge tank is pumped into the first-stage centrifuge by the feed pump, and the first-stage centrifuge applies centrifugal action to the sludge. Under the centrifugal action, the sand particles in the sludge rub against the sludge bacterial flocs, and self-decomposition occurs, so that the sludge is separated from top to bottom into supernatant, biochemical sludge sediment and sand and gravel particles in the first-stage centrifuge. The supernatant and the biochemical sludge sediment then enter the heating box, and the heating box heats the supernatant and the biochemical sludge sediment to loosen the EPS of the biochemical sludge sediment and destroy the cross-linking structure between the EPS. Then the self-priming pump pumps the liquid in the heating box into the second-stage centrifuge, and the second-stage centrifuge applies centrifugal action to the liquid again, so that the liquid is separated from top to bottom into supernatant and biochemical sludge sediment in the second-stage centrifuge. The obtained supernatant is EPS, and there is no need to add various decomposition-promoting drugs or perform ultrasonic treatment, so it will not cause excessive cell rupture, which effectively improves the problem of excessive cell rupture when extracting extracellular polymers in wastewater treatment.
[0009] Optionally, a stirring brush is detachably provided on the central axis of the first-stage centrifuge.
[0010] By adopting the above technical solution, when the central axis of the first-stage centrifuge rotates to apply centrifugal force to the sludge, it drives the stirring brush to rotate, and the stirring brush further breaks up the sludge bacterial flocs, thereby improving the efficiency of sludge treatment, and avoiding cell breakage through the flexibility of the brush.
[0011] Optionally, the stirring brush includes an outer jacket and a plastic brush, the outer jacket is arranged on the central axis of the first-stage centrifuge by bolts, and a plurality of the plastic brushes are arranged on the outer jacket.
[0012] By adopting the above technical solution, when processing sludge of different properties, the staff can unscrew the bolts that fix the outer jacket and replace the outer jacket with bristles of different hardness, softness and length on the central axis of the first-stage centrifuge, thereby improving the applicability of the stirring brush to sludge of different properties.
[0013] Optionally, a discharge valve is provided at the connection point between the first-stage centrifuge and the heating box, and the height of the connection point between the first-stage centrifuge and the heating box is higher than the height of the heating box.
[0014] By adopting the above technical solution, the height of the connection point between the first-stage centrifuge and the heating box is higher than the height of the heating box, and the discharge valve is opened, so that the supernatant and biochemical sludge sediment in the first-stage centrifuge can automatically enter the heating box under the action of gravity, thereby improving the convenience of the supernatant and biochemical sludge sediment in the first-stage centrifuge entering the heating box.
[0015] Optionally, the lower parts of the first-stage centrifuge and the second-stage centrifuge are both connected to each other and are provided with mud discharge outlets, and the mud discharge outlets are provided with mud discharge valves.
[0016] By adopting the above technical solution, after the centrifugation of the first-stage centrifuge is completed, the sand and gravel particles are settled at the lower part of the first-stage centrifuge under the action of gravity. By opening the mud discharge valve on the mud discharge port of the first-stage centrifuge, the sand and gravel particles can be conveniently and quickly discharged from the first-stage centrifuge; after the centrifugation of the second-stage centrifuge is completed, the biochemical sludge sediment is settled at the lower part of the second-stage centrifuge. By opening the mud discharge valve on the mud discharge port of the second-stage centrifuge, the sand and gravel particles can be conveniently and quickly discharged from the second-stage centrifuge.
[0017] Optionally, the inner side wall of the first-stage centrifuge is covered with a rubber lining.
[0018] By adopting the above technical solution, the rubber lining covers the inner wall of the first-stage centrifuge, thereby preventing the sand and gravel particles from wearing the first-stage centrifuge housing and increasing the service life of the first-stage centrifuge.
[0019] Optionally, the inner wall of the secondary centrifuge is covered with a polytetrafluoroethylene plate.
[0020] By adopting the above technical solution, the polytetrafluoroethylene plate covers the inner wall of the secondary centrifuge, thereby reducing the wear of the inner wall of the secondary centrifuge by the biochemical sludge sediment, reducing the friction and shear of the secondary centrifuge on the microorganisms, reducing the adhesion of microorganisms to the inner wall of the secondary centrifuge, and thus reducing the damage of the secondary centrifuge to the microbial cells.
[0021] Optionally, a stirring paddle for stirring the liquid is provided in the heating box.
[0022] By adopting the above technical solution, when the heating box heats the liquid, the stirring paddle stirs the liquid, thereby improving the uniformity and heating efficiency of the liquid in the heating box.
[0023] In summary, the present application includes at least one of the following beneficial technical effects:
[0024] 1. No need to add various decomposition-promoting drugs or perform ultrasonic treatment, so it will not cause excessive cell rupture, effectively improving the problem of excessive cell rupture when extracting extracellular polymers in wastewater treatment;
[0025] 2. The stirring brush further breaks up the sludge bacterial flocs, improving the efficiency of sludge treatment, and avoids cell breakage through the flexibility of the brush;
[0026] 3. The polytetrafluoroethylene plate covers the inner wall of the secondary centrifuge to reduce the wear of the inner wall of the secondary centrifuge by the biochemical sludge sediment, reduce the friction and shear of the secondary centrifuge on the microorganisms, reduce the adhesion of microorganisms on the inner wall of the secondary centrifuge, and thus reduce the damage of the secondary centrifuge to the microbial cells. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a schematic cross-sectional structure diagram of a two-stage centrifugal device for efficiently extracting and concentrating sludge EPS in an embodiment of the present application.
[0028] Figure numerals: 1, frame; 2, first-stage centrifuge; 3, feed pump; 4, heating box; 5, second-stage centrifuge; 6, self-priming pump; 7, stirring brush; 71, outer jacket; 72, plastic brush; 8, discharge valve; 9, mud discharge port; 10, mud discharge valve; 11, rubber lining; 12, polytetrafluoroethylene plate; 13, stirring paddle; 14, discharge port; 15, control valve; 16, plastic buffer plate. DETAILED DESCRIPTION
[0029] The following is combined with Figure 1 This application is described in further detail.
[0030] The embodiment of the present application discloses a two-stage centrifugal device for efficiently extracting concentrated sludge EPS.
[0031] Reference Figure 1 The two-stage centrifugal device for efficiently extracting concentrated sludge EPS includes a frame 1, a first-stage centrifuge 2, a feed pump 3, a heating box 4, a second-stage centrifuge 5 and a self-priming pump 6.
[0032] Reference Figure 1 The first-stage centrifuge 2 is installed on the frame 1. The first-stage centrifuge 2 is used to apply centrifugal force to the sludge. In this embodiment, the first-stage centrifuge 2 includes a tank body, a central shaft and a driving motor. The tank body is installed on the frame 1. The central shaft is rotatably installed on the tank body and extends into the tank body. The driving motor is installed on the tank body. The output shaft of the driving motor is coaxially connected with the central shaft. The tank body is connected to the concentrated sludge tank through a pipeline. The feed pump 3 is installed on the frame 1. The feed pump 3 is used to pump the sludge in the concentrated sludge tank into the tank body. Valves are installed on the pipelines connected to the suction port and the discharge port of the feed pump 3 to facilitate the control of the sludge transportation.
[0033] The drive motor is started, and the output shaft of the drive motor drives the central shaft to rotate, so that the central shaft speed is maintained at 800-1000rpm, the centrifugal acceleration is 1200-1700g, and the centrifugal time is 5min. During the rotation process, the central shaft exerts centrifugal force on the sludge in the tank body, so that the sand particles in the concentrated sludge are rubbed with the sludge bacterial flocs under the centrifugal action, and self-decomposition occurs.
[0034] Reference Figure 1 , a stirring brush 7 is detachably mounted on the central axis of the first-stage centrifuge 2, and the stirring brush 7 includes a jacket 71 and a plastic brush 72. The jacket 71 is coaxially mounted on the central axis of the first-stage centrifuge 2 by bolts, and the plastic brush 72 is mounted on the jacket 71 in an array. When the central axis of the first-stage centrifuge 2 rotates, the jacket 71 and the plastic brush 72 are driven to rotate, and the plastic brush 72 can further break the sludge bacterial flocs, and the flexibility of the plastic brush 72 can avoid cell breakage; when processing sludge of different properties, the staff removes the jacket 71 from the central axis of the first-stage centrifuge 2, and then installs the jacket 71 with bristles of different hardness and length to the central axis of the first-stage centrifuge 2, so that the stirring brush 7 can be replaced according to the sludge of different properties, thereby improving the applicability of the stirring brush 7 to sludge of different properties.
[0035] Reference Figure 1 The inner wall of the first-stage centrifuge 2 is covered with a rubber lining 11. The rubber lining 11 covers the inner wall of the first-stage centrifuge 2 to prevent the sand and gravel particles from wearing the shell of the first-stage centrifuge 2 and improve the service life of the first-stage centrifuge 2.
[0036] Reference Figure 1 The heating box 4 is connected and installed on the first-stage centrifuge 2. The heating box 4 is used to heat the liquid after centrifugation by the first-stage centrifuge 2. In this embodiment, the heating box 4 includes a box body and an electric heating rod. The heating box 4 is installed on the first-stage centrifuge 2. The electric heating rod is installed in the heating box 4. The electric heating rod is connected to the power supply. When heating is required, the electric heating rod is connected to the power supply, and the electric heating rod generates heat to heat the liquid in the box body.
[0037] Reference Figure 1 A discharge valve 8 is installed at the connection point between the primary centrifuge 2 and the heating box 4, and the height of the connection point between the primary centrifuge 2 and the heating box 4 is higher than the height of the heating box 4. By opening the discharge valve 8, the supernatant and biochemical sludge sediment in the primary centrifuge 2 can automatically enter the heating box 4 under the action of gravity, thereby improving the convenience of the supernatant and biochemical sludge sediment in the primary centrifuge 2 entering the heating box 4.
[0038] Reference Figure 1 A stirring paddle 13 is installed in the heating box 4. The stirring paddle 13 is used to stir the liquid in the heating box 4. In this embodiment, the stirring paddle 13 includes a driving shaft, a paddle and a stirring motor. The driving shaft is rotatably mounted on the top wall of the heating box 4, the paddle is mounted on the driving shaft, the stirring motor is mounted on the heating box 4, and the output shaft of the stirring motor is coaxially connected with the driving shaft. When the heating box 4 heats the liquid, the stirring motor is started, the stirring motor drives the driving shaft to rotate, the driving shaft drives the paddle to rotate, and the paddle stirs the liquid, thereby improving the uniformity and heating efficiency of the liquid in the heating box 4.
[0039] Reference Figure 1 , the secondary centrifuge 5 is installed on the frame 1, the secondary centrifuge 5 is connected to the heating box 4, the secondary centrifuge 5 is used to apply centrifugal action to the heated liquid again, the secondary centrifuge 5 centrifuges the liquid for 5-10 minutes, the rotation speed is 3000-3500rpm, and the centrifugal acceleration is about 5000-6000g. In this embodiment, the structure of the secondary centrifuge 5 is the same as that of the primary centrifuge 2, and a stirring rod is installed on the central axis of the secondary centrifuge 5. The stirring rod increases the diameter of the central axis of the secondary centrifuge 5, thereby increasing the centrifugal force applied to the liquid when the central axis of the secondary centrifuge 5 rotates; the self-priming pump 6 is installed on the frame 1, and the self-priming pump 6 is used to pump the liquid in the heating box 4 into the secondary centrifuge 5.
[0040] In this embodiment, a discharge port 14 is connected to and installed on the secondary centrifuge 5, a control valve 15 is installed on the discharge port 14, and a plastic buffer plate 16 is also installed on the inner side wall of the secondary centrifuge 5 at the discharge port 14. After the secondary centrifuge 5 completes the centrifugal action on the liquid, the control valve 15 is opened to conveniently and quickly discharge the supernatant in the secondary centrifuge 5, and during the discharge process, the plastic buffer plate 16 reduces the impact force of the supernatant on the discharge port 14 and the inner side wall of the secondary centrifuge 5.
[0041] Reference Figure 1 The lower parts of the primary centrifuge 2 and the secondary centrifuge 5 are both connected and equipped with a mud discharge port 9, which is connected to the filter press system of the sewage treatment plant. A mud discharge valve 10 is installed on the mud discharge port 9. In this embodiment, the lower parts of the primary centrifuge 2 and the secondary centrifuge 5 are both funnel-shaped. After the staff opens the mud discharge valve 10, the sand and gravel particles in the sludge can automatically accumulate at the bottom of the primary centrifuge 2 under the action of gravity and be discharged from the mud discharge port 9 of the primary centrifuge 2 to the filter press system, so that the sand and gravel particles can be discharged from the primary centrifuge 2 conveniently and quickly, and the biochemical sludge sediment can automatically accumulate at the bottom of the secondary centrifuge 5 under the action of gravity and be discharged from the filter press system from the mud discharge port 9 of the secondary centrifuge 5, so that the sand and gravel particles can be discharged from the secondary centrifuge 5 conveniently and quickly.
[0042] Reference Figure 1 The inner wall of the secondary centrifuge 5 is covered with a polytetrafluoroethylene plate 12. The polytetrafluoroethylene plate 12 has high lubricity, corrosion resistance, non-adhesion and other characteristics, which reduces the wear of the inner wall of the secondary centrifuge 5 by the biochemical sludge sediment, reduces the friction and shear of the secondary centrifuge 5 on the microorganisms, reduces the adhesion of microorganisms to the inner wall of the secondary centrifuge 5, and thus reduces the damage of the secondary centrifuge 5 to the microbial cells.
[0043] The implementation principle of a two-stage centrifugal device for efficiently extracting and concentrating sludge EPS in the embodiment of the present application is as follows: the sludge in the sludge pool is pumped into the first-stage centrifuge 2 by the feed pump 3, and the first-stage centrifuge 2 applies centrifugal action to the sludge. Under the centrifugal action, the sand particles in the sludge rub against the sludge bacterial flocs, and at the same time, the stirring brush 7 breaks the sludge bacterial flocs while avoiding breaking the cells, so that the sludge undergoes self-deconstruction. The sludge is divided into supernatant, biochemical sludge sediment and sand and gravel particles from top to bottom in the first-stage centrifuge 2. The supernatant and the biochemical sludge sediment then enter the heating box 4, which heats the supernatant and the biochemical sludge sediment. During the heating process, the stirring paddle 13 stirs the liquid to loosen the EPS of the biochemical sludge sediment and destroy the cross-linked structure between the EPS. Then the self-priming pump 6 then pumps the liquid in the heating box 4. The liquid is pumped into the secondary centrifuge 5, and the secondary centrifuge 5 applies centrifugal action to the liquid again. During the process, the polytetrafluoroethylene plate 12 reduces the damage to the microbial cells, so that the liquid is divided into a supernatant and a biochemical sludge sediment from top to bottom in the secondary centrifuge 5. The obtained supernatant is EPS, and there is no need to add various decomposition-promoting drugs or perform ultrasonic treatment. The centrifugal speeds of the primary centrifuge 2 and the secondary centrifuge 5 are much lower than those of the prior art, so too many cells will not be ruptured, which effectively improves the problem of too many cells being easily ruptured when extracting extracellular polymers in wastewater treatment. In addition, through the two-stage centrifugal action on the sludge, the mass of the sand and gravel collected by the primary centrifuge 2 and the biochemical sludge sediment collected by the secondary centrifuge 5 is much smaller than the mass of the concentrated sludge during feeding, so the device also has the functions of sludge dehydration and sludge reduction.
[0044] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A two-stage centrifugal device for efficiently extracting and concentrating sludge EPS, characterized by: The invention comprises a frame (1), a primary centrifuge (2), a feed pump (3), a heating box (4), a secondary centrifuge (5) and a self-priming pump (6), wherein the primary centrifuge (2) is arranged on the frame (1) and is used to apply a centrifugal action to the sludge, and the feed pump (3) is arranged on the frame (1) and is used to pump the sludge in the concentrated sludge tank into the primary centrifuge (2); the heating box (4) is arranged on the primary centrifuge (2) and is used to heat the liquid after centrifugation by the primary centrifuge (2); the secondary centrifuge (5) is arranged on the heating box (4) and is used to apply a centrifugal action to the heated liquid again; and the self-priming pump (6) is arranged on the frame (1) and is used to pump the liquid in the heating box (4) into the secondary centrifuge (5).
2. A two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1, characterized in that: A stirring brush (7) is detachably provided on the central axis of the primary centrifuge (2).
3. A two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 2, characterized in that: The stirring brush (7) comprises an outer cover (71) and a plastic brush (72); the outer cover (71) is arranged on the central axis of the first-stage centrifuge (2) by means of bolts; and a plurality of the plastic brushes (72) are arranged on the outer cover (71).
4. A two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1, characterized in that: A discharge valve (8) is provided at the connection point between the primary centrifuge (2) and the heating box (4), and the height of the connection point between the primary centrifuge (2) and the heating box (4) is higher than the height of the heating box (4).
5. The two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1 is characterized in that: The lower parts of the first-stage centrifuge (2) and the second-stage centrifuge (5) are both connected and provided with a mud discharge port (9), and the mud discharge port (9) is provided with a mud discharge valve (10).
6. The two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1 is characterized in that: The inner side wall of the first-stage centrifuge (2) is covered with a rubber lining (11).
7. The two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1 is characterized in that: The inner side wall of the secondary centrifuge (5) is covered with a polytetrafluoroethylene plate (12).
8. The two-stage centrifugal device for efficiently extracting and concentrating sludge EPS according to claim 1 is characterized in that: A stirring paddle (13) for stirring the liquid is arranged in the heating box (4).