Method and system for biodegrading sludge

Abstract

The invention relates to a method and system for biologically degrading sludge, and the method comprises the following steps: S01, pretreating sewage to remove large-particle impurities and inorganic sand grains in the sewage; s02, performing microbiological treatment on the pretreated sewage, and degrading, converting or removing pollutants in the sewage by utilizing metabolic activity of microorganisms so as to purify the sewage; s03, the purified sewage is subjected to precipitation treatment, sludge precipitation is performed, and separation of sludge and water is achieved; and S04, carrying out digestion treatment on the settled sludge, so that the sludge is in a delayed aeration and self-degradation state, and completing sludge degradation. According to the technical scheme, the sewage is subjected to preliminary pretreatment, microbiological treatment and precipitation treatment, then purified water is separated from sludge, the purified water can be discharged or subjected to subsequent advanced treatment, the precipitated sludge is further subjected to digestion treatment, the sludge can be degraded through digestion treatment, and the sludge can be recycled. Therefore, the total amount of sludge can be reduced by more than 90%.

Description

Technical Field

[0001] The present invention relates to the technical field of biodegradation, and particularly relates to a method and a system for biodegradating sludge. Background Art

[0002] With the rapid economic development, the amounts of municipal, industrial wastewater and domestic sewage are continuously increasing. Part of this wastewater, together with the domestic sewage generated by the original residents, is directly discharged into the surrounding water bodies without any treatment, seriously polluting the surface water quality. If no pollution control measures are taken, it will directly affect people's quality of life and living environment.

[0003] The existing sewage treatment methods generally use the biofilm method. The biofilm method is a biological treatment method in which fillers are added to allow microorganisms to grow and multiply on the surface of the fillers to form an activated sludge biofilm to degrade nutrients in the sewage. The sewage sediment sludge treated by the biofilm method is generally incinerated or landfilled, but the sludge cannot be further reduced in quantity. Summary of the Invention

[0004] Therefore, a method and a system for biodegradating sludge are needed to solve the technical problem that the sewage sediment sludge treated by the biofilm method is generally incinerated or landfilled, but the sludge cannot be further reduced in quantity.

[0005] To achieve the above object, in a first aspect, the present invention provides a method for biodegradating sludge, including:

[0006] S01: Pretreat the sewage to remove large particle impurities and inorganic sand grains in the sewage;

[0007] S02: Microbially treat the pretreated sewage, and use the metabolic activities of microorganisms to degrade, transform or remove pollutants in the sewage to purify the sewage;

[0008] S03: Perform sedimentation treatment on the purified sewage to precipitate the sludge to achieve the separation of the sludge and water;

[0009] S04: Digest the precipitated sludge to make the sludge in the state of extended aeration and self-degradation to complete sludge degradation.

[0010] As an embodiment of the present invention, in step S04, the digestion treatment includes sludge collection, anaerobic digestion treatment, aerobic digestion treatment and facultative anaerobic digestion treatment.

[0011] In this way, by subjecting the collected sludge to different digestion treatment methods (anaerobic, aerobic and facultative anaerobic), the sludge stability can be significantly improved, the volume can be reduced, the pollution risk can be reduced, and resource utilization can be achieved.

[0012] As an embodiment of the present invention, sludge collection specifically includes collecting the settled sludge in a sludge collection tank, and discharging the sludge in a quantitative manner through a sludge pump installed in the sludge collection tank.

[0013] In this way, the precipitated sludge can be collected uniformly through the sludge collection tank, and the sludge can be discharged quantitatively through the sludge pump. Therefore, the discharge frequency of the sludge pump can be automatically adjusted according to actual conditions.

[0014] As an embodiment of the present invention, the anaerobic digestion treatment is specifically as follows: a sludge pump discharges sludge into an anaerobic digester in a quantitative manner, and a first three-phase separator installed in the anaerobic digester smoothly separates the sludge into gas, liquid and solid, and the separated supernatant liquid then flows out through a first overflow trough installed in the anaerobic digester.

[0015] In this way, anaerobic microorganisms decompose organic matter, and the anaerobic digester causes the sludge to anaerobically produce methane (methane can be used for power generation) and simultaneously produce anaerobic bacteria agents (which can be used for sewage treatment commissioning and introduction) and soil conditioners as by-products.

[0016] As an embodiment of the present invention, the aerobic digestion treatment is specifically as follows: the separated upper layer liquid flows into the aerobic digester through the first overflow trough, and the oxygen is efficiently and evenly dispersed into the sewage by installing a first aeration plate in the aerobic digester, providing the required dissolved oxygen for microbial metabolism to promote the mixing and reaction of the clear liquid, and the upper mixed liquid then flows out through the second overflow trough installed in the aerobic digester.

[0017] This process increases oxygen transfer efficiency by 25%-30% through the first aeration plate, promoting endogenous microbial respiration and reducing sludge volume by 30%-40%. Furthermore, in addition to reducing sludge volume, it also produces aerobic bacteria and soil conditioners.

[0018] As an embodiment of the present invention, the facultative anoxic digestion treatment is specifically as follows: the upper mixed liquor flows into the facultative anoxic digester through the second overflow trough, the facultative anoxic digester efficiently degrades the mixed liquor, and the upper clear liquor flows out through the third overflow trough installed in the facultative anoxic digester.

[0019] This creates a facultative aerobic environment between anaerobic and aerobic conditions. By controlling the dissolved oxygen concentration (microaerobic environment), it promotes the decomposition of organic matter by facultative bacteria. In this microaerobic environment, short-term nitrification and denitrification simultaneously remove nitrogen and phosphorus, reducing the amount of chemical agents added. Furthermore, facultative aerobic agents and soil conditioners can be produced as byproducts.

[0020] As an embodiment of the present invention, after step S04 of "digesting the precipitated sludge to put the sludge into a state of delayed aeration and self-degradation to complete sludge degradation", step S05 is also included:

[0021] The digested sludge is returned to step S02 again and undergoes microbial treatment together with the pretreated sewage.

[0022] In this way, the digested sludge and the pretreated sewage can be subjected to microbial treatment together, improving the utilization of the sludge and further degrading the sludge.

[0023] As an implementation manner of the present invention, in step S01, the pretreatment includes grille treatment, conditioning treatment, and grit removal treatment.

[0024] In this way, the grille treatment uses coarse and fine grilles for hierarchical interception to remove suspended solids with a particle size > 5 mm in the sewage. The conditioning treatment equalizes the water quality and quantity through the hydraulic retention time (HRT = 4 - 6 h) to buffer the influent fluctuation. The grit removal treatment uses a vortex grit chamber to remove inorganic sand grains with a density > 2.65 g / cm 3 (such as quartz sand and metal chips). In addition, the precipitated inorganic sand grains can be further separated by a sand - water separator to obtain sand.

[0025] As an implementation manner of the present invention, in step S02, the microbial treatment includes anaerobic treatment, anoxic treatment, and aerobic treatment.

[0026] In this way, through the "anaerobic - anoxic - aerobic" coupling process, the efficient removal of carbon, nitrogen, and phosphorus is achieved synchronously (the TP removal rate > 80%), avoiding the limitations of a single treatment mode. In addition, the sludge production can be reduced. Specifically, the anaerobic section degrades macromolecular organic matter, reducing the amount of microbial proliferation in the subsequent aerobic section, and the sludge volume is reduced by 30% - 50%.

[0027] To achieve the above - mentioned purpose, in the second aspect, the present invention also provides a system for biodegradable sludge, which is used to execute the method for biodegradable sludge provided by any one of the above - mentioned inventors.

[0028] Different from the prior art, the technical solution of the present application, in addition to performing preliminary pretreatment, microbial treatment, and sedimentation treatment on the sewage, separates the purified water from the sludge. The purified water can be discharged or subjected to subsequent advanced treatment, while the precipitated sludge is further digested. The digestion treatment can degrade the sludge, so that the overall sludge reduction amount can reach more than 90%.

[0029] The above - mentioned related records of the invention content are only an overview of the technical solution of the present application. In order to enable those of ordinary skill in the art to more clearly understand the technical solution of the present application, and then can be implemented according to the content recorded in the description and the drawings, and in order to make the above - mentioned purpose, other purposes, features, and advantages of the present application more easily understood, the following is described in conjunction with the specific implementation manners and drawings of the present application. Brief Description of the Drawings

[0030] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, effects, etc. of the specific embodiments of the present application and other related contents, and should not be considered as a limitation to the present application.

[0031] In the accompanying drawings of the specification:

[0032] Figure 1 is the flowchart of the method for biodegradable sludge in an embodiment of the present application Figure 1 ;

[0033] Figure 2 is the flowchart of the method for biodegradable sludge in an embodiment of the present application Figure 2 ;

[0034] Figure 3 is the structural schematic diagram of the system for biodegradable sludge in an embodiment of the present application;

[0035] Figure 4 is the structural schematic diagram of the digestion treatment device in an embodiment of the present application;

[0036] Figure 5 is the structural schematic diagram of the first promoting sludge reaction mechanism in an embodiment of the present application;

[0037] Figure 6 is another structural schematic diagram of the first promoting sludge reaction mechanism in an embodiment of the present application;

[0038] Figure 7 is the flowchart of the method for biodegradable sludge in an embodiment of the present application Figure 3 ;

[0039] Figure 8 is the structural schematic diagram of the pretreatment device in an embodiment of the present application;

[0040] Figure 9 is the flowchart of the method for biodegradable sludge in an embodiment of the present application Figure 4 ;

[0041] Figure 10 is the structural schematic diagram of the microbial treatment device in an embodiment of the present application;

[0042] Figure 11 is the flowchart of the method for biodegradable sludge in an embodiment of the present application Figure 5 ;

[0043] Figure 12 is the control flowchart of the control system for biodegradable sludge in an embodiment of the present application.

[0044] The descriptions of the reference numerals involved in the above-mentioned accompanying drawings are as follows:

[0045] 1 - Pretreatment device; 11 - Grid tank; 12 - Regulation tank; 13 - Water pump; 14 - Electromagnetic flowmeter; 15 - Grit chamber; 16 - Grit and water separator; 2 - Microbial treatment device; 21 - First AHBBR tank; 211 - Circulation pump; 212 - Fourth overflow trough; 213 - Second three-phase separator; 22 - Second AHBBR tank; 221 - Agitator; 222 - Second sludge concentration detector; 223 - Fifth overflow trough; 23 - OHBBR tank; 231 - Second aeration disc; 232 - Third sludge concentration detector; 233 - Dissolved oxygen concentration detector; 24 - Microbial material; 25 - Second sludge reaction promoting mechanism; 3 - Secondary sedimentation tank; 31 - First vertical pipe; 32 - Sixth overflow trough; 4 - Digestion treatment device; 41 - Sludge collection tank; 42 - Sludge pump; 431 - Anaerobic digestion tank; 432 - First three-phase separator; 433 - First overflow trough; 434 - First microbial enhancement plate; 441 - Aerobic digestion tank; 442 - First aeration disc; 443 - Blower; 444 - Second overflow trough; 445 - First sludge concentration detector; 451 - Anoxic digestion tank; 452 - Third overflow trough; 453 - Second vertical pipe; 46 - First sludge reaction promoting mechanism. Detailed implementation manners

[0046] To describe in detail the possible application scenarios, technical principles, specific implementable solutions, achievable purposes and effects of the present application, the following is described in detail with reference to the specific examples listed and in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, so they are only examples and cannot be used to limit the protection scope of the present application.

[0047] Referring to "embodiment" herein means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The term "embodiment" appearing in various positions in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0048] Unless otherwise defined, the meanings of the technical terms used herein are the same as those commonly understood by those skilled in the technical field to which the present application belongs; the use of the relevant terms herein is only for describing specific embodiments and is not intended to limit the present application.

[0049] In the description of the present application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that there can be three relationships. For example, A and / or B means: there is A, there is B, and there is both A and B at the same time. In addition, the character " / " in this text generally represents an "or" logical relationship between the associated objects before and after.

[0050] In the present application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantitative, primary-secondary, or sequential relationships between these entities or operations.

[0051] Without further limitations, in the present application, the open-ended expressions such as "include", "comprise", "have" or other similar expressions used in a statement are intended to cover non-exclusive inclusion. These expressions do not exclude the possibility that there may be additional elements in the process, method or product including the said elements. Thus, a process, method or product including a series of elements may include not only those defined elements, but also other elements not explicitly listed, or elements inherent to such process, method or product.

[0052] Similar to the understanding in the "Examination Guidelines", in the present application, expressions such as "greater than", "less than", "exceeding" are understood not to include the number itself; expressions such as "above", "below", "within" are understood to include the number itself. In addition, in the description of the embodiments of the present application, the meaning of "a plurality of" is two or more (including two). Similar expressions related to "many", such as "multiple groups", "multiple times", etc., are understood in the same way, unless otherwise specifically limited.

[0053] In the description of the embodiments of the present application, the spatially related expressions used, such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "perpendicular", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiment or the drawing. It is only for the convenience of describing the specific embodiments of the present application or for the reader's understanding, rather than indicating or implying that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, it should not be construed as a limitation to the embodiments of the present application.

[0054] Unless otherwise clearly specified or defined, in the description of the embodiments of the present application, terms such as "installation", "connection", "attachment", "fixation", "setting", etc. shall be understood in a broad sense. For example, the "connection" may be a fixed connection, a detachable connection, or an integral setting; it may be directly connected, or indirectly connected through an intermediate medium; it may be a relationship in which two components are combined together, or an interaction relationship between two components, or a connection inside two structures. For those skilled in the art to which the present application pertains, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0055] For the sewage sediment sludge treated by the biological membrane method, generally the precipitated sludge is incinerated or landfilled, but the sludge cannot be further reduced in quantity. In view of this, the embodiments of the present application provide a method for biodegradation of sludge, including:

[0056] S01: Pretreat the sewage to remove large particulate impurities and inorganic sand grains in the sewage;

[0057] S02: Subject the pretreated sewage to microbial treatment, and utilize the metabolic activities of microorganisms to degrade, transform or remove pollutants in the sewage to purify the sewage;

[0058] S03: Subject the purified sewage to sedimentation treatment, and the sludge precipitates to achieve the separation of the sludge from the water;

[0059] S04: Digest the precipitated sludge to make the sludge in a state of extended aeration and self-degradation, and complete the sludge degradation.

[0060] According to some embodiments of the present application, please refer to Figures 1 to 12 , this embodiment relates to a method for biodegradation of sludge, including:

[0061] S01: Pretreat the sewage to remove large particulate impurities and inorganic sand grains in the sewage;

[0062] S02: Subject the pretreated sewage to microbial treatment, and utilize the metabolic activities of microorganisms to degrade, transform or remove pollutants in the sewage to purify the sewage;

[0063] S03: Subject the purified sewage to sedimentation treatment, and the sludge precipitates to achieve the separation of the sludge from the water;

[0064] S04: Digest the precipitated sludge to make the sludge in a state of extended aeration and self-degradation, and complete the sludge degradation.

[0065] It should be specifically explained in step S03 that the sedimentation treatment is specifically that the purified sewage can be precipitated through the secondary sedimentation tank 3, and the secondary sedimentation tank 3 separates the sludge and water into solids and liquids. Among them, the upper part of the secondary sedimentation tank 3 is provided with a first vertical flow pipe 31 and a sixth overflow trough 32. Water enters the secondary sedimentation tank 3 through the first vertical flow pipe 31, and the purified water can be discharged through the sixth overflow trough 32 or undergo subsequent deep treatment (subsequent deep treatment includes filtration and disinfection modules to ensure that the effluent meets the discharge standards). Optionally, the bottom of the secondary sedimentation tank 3 is in the shape of an inclined bucket to facilitate sedimentation.

[0066] In addition to performing preliminary pretreatment, microbial treatment, and sedimentation treatment on sewage to separate the purified water from the sludge, the technical solution of the present application can discharge the purified water or undergo subsequent deep treatment, while the precipitated sludge is further subjected to digestion treatment. The digestion treatment can degrade the sludge, thereby reducing the total amount of sludge by more than 90%.

[0067] like Figures 2 to 4 and Figure 11 As shown, in step S04, the digestion treatment includes sludge collection, anaerobic digestion treatment, aerobic digestion treatment and facultative aerobic digestion treatment.

[0068] The digestion treatment can be carried out by the digestion treatment device 4. In this way, by subjecting the collected sludge to different digestion treatment methods (anaerobic, aerobic and facultative aerobic), the sludge stability can be significantly improved, the volume can be reduced, the pollution risk can be reduced, and resource utilization can be achieved.

[0069] like Figures 2 to 4 and Figure 11 As shown, the sludge collection is specifically to collect the settled sludge through a sludge collection tank 41 and discharge the sludge quantitatively through a sludge pump 42 installed in the sludge collection tank 41 .

[0070] The digestion treatment device 4 includes a sludge collection tank 41 and a sludge pump 42. Thus, the sludge after settling can be collected uniformly by the sludge collection tank 41, and the sludge can be discharged quantitatively by the sludge pump 42. Thus, the discharge frequency of the sludge pump 42 can be automatically adjusted according to actual conditions.

[0071] like Figures 2 to 4 and Figure 11 As shown, the anaerobic digestion treatment is specifically as follows: the sludge pump 42 discharges the sludge into the anaerobic digester 431 in a quantitative manner, and the sludge is smoothly separated into gas, liquid and solid through the first three-phase separator 432 installed in the anaerobic digester 431, and the supernatant liquid after separation flows out through the first overflow trough 433 installed in the anaerobic digester 431.

[0072] The digestion treatment device 4 further includes an anaerobic digestion tank 431, a first three-phase separator 432, and a first overflow tank 433. In some embodiments, the digestion treatment device 4 further includes a first microbial enhancement plate 434, which can enhance the microbial metabolism efficiency. Especially in the anaerobic digestion tank 431, it can accelerate the conversion of organic matter into methane, prevent sludge caking, and maintain the efficient operation of the first three-phase separator 432.

[0073] In this way, through the decomposition of organic matter by anaerobic microorganisms, the anaerobic digestion tank 431 anaerobically generates methane from sludge (methane can be used for power generation), and simultaneously by-produces anaerobic bactericide (which can be used for sewage treatment debugging and strain introduction) and soil conditioner.

[0074] As Figures 2 to 4 and Figure 11 shown, the aerobic digestion treatment is specifically as follows: the separated upper-layer liquid flows into the aerobic digestion tank 441 through the first overflow tank 433, and the first aeration disk 442 installed in the aerobic digestion tank 441 efficiently and evenly disperses oxygen into the sewage to provide the required dissolved oxygen for microbial metabolism, so as to promote the mixing and reaction of the supernatant. The upper-layer mixed liquid then flows out through the second overflow tank 444 installed in the aerobic digestion tank 441.

[0075] The digestion treatment device 4 further includes an aerobic digestion tank 441, a first aeration disk 442, a blower 443, and a second overflow tank 444. The blower 443 supplies gas to the first aeration disk 442. Among them, the first aeration disk 442 can extend the aeration time, thereby increasing the sludge retention time. In some embodiments, the aerobic digestion tank 441 further includes a first sludge concentration detector 445, which detects the sludge concentration in the aerobic digestion tank 441. Preferably, the first sludge concentration detector 445 is communicatively connected to the blower 443, and the gas supply volume or gas supply time of the blower 443 can be adjusted according to the sludge concentration detected by the first sludge concentration detector 445, so as to adjust the aeration volume or aeration time of the first aeration disk 442.

[0076] In this way, through the first aeration disk 442, the oxygen transfer efficiency can reach 25%-30%, promoting the endogenous respiration of microorganisms and reducing the sludge volume by 30%-40%. In addition, in addition to reducing the sludge volume, aerobic bactericide and soil conditioner can also be by-produced.

[0077] As Figures 2 to 4 and Figure 11 shown, the anoxic digestion treatment is specifically as follows: the upper-layer mixed liquid flows into the anoxic digestion tank 451 through the second overflow tank 444, and the anoxic digestion tank 451 efficiently degrades the mixed liquid. The upper-layer clear liquid then flows out through the third overflow tank 452 installed in the anoxic digestion tank 451.

[0078] The digestion treatment device 4 further includes an anoxic digestion tank 451 and a third overflow tank 452. Among them, a second vertical flow pipe 453 is arranged in the upper part of the anoxic digestion tank 451, and the water inlet of the second vertical flow pipe 453 is communicated with the water outlet of the second overflow tank 444. Optionally, the bottom of the anoxic digestion tank 451 is in the shape of an inclined hopper, which is convenient for sedimentation.

[0079] In this way, anoxia is between anaerobic and aerobic. By controlling the dissolved oxygen concentration (micro-aerobic environment), it promotes the decomposition of organic matter by facultative bacteria. In the micro-aerobic environment, short-cut nitrification and denitrification synchronously remove nitrogen and phosphorus, reducing the dosage of chemical agents. In addition, anoxic bacterial agents and soil conditioners can also be by-produced.

[0080] As Figure 5 and Figure 6 shown, the digestion treatment device 4 further includes a first sludge reaction promoting mechanism 46. The first sludge reaction promoting mechanism 46 can be installed in the anaerobic digestion tank 431 and / or the aerobic digestion tank 441 and / or the anoxic digestion tank 451. The first sludge reaction promoting mechanism 46 can improve the sludge degradation efficiency. The first sludge reaction promoting mechanism 46 can be a sludge stratification rack or an inclined plate. The sludge stratification rack can stratify the sludge, increasing the contact area between the sludge and microorganisms, thereby improving the sludge degradation efficiency. The inclined plate can enhance the attachment of biofilm and the enrichment of microorganisms, and can also extend the hydraulic retention time to avoid short-circuit flow or dead zones.

[0081] As Figure 3 , Figure 4 and Figure 11 shown, after step S04 "digesting the precipitated sludge to make the sludge in the state of extended aeration and self-degradation to complete sludge degradation", it further includes step S05:

[0082] Return the digested sludge back to step S02 again to perform microbial treatment together with the pretreated sewage.

[0083] In this way, the digested sludge can be subjected to microbial treatment together with the pretreated sewage, improving the utilization of the sludge and further degrading the sludge.

[0084] As Figure 7 , Figure 8 and Figure 11 shown, in step S01, the pretreatment includes grid treatment, adjustment treatment, and grit removal treatment.

[0085] Pretreatment can be carried out by the pretreatment device 1. Specifically, the pretreatment device 1 includes a grid tank 11 for grid treatment, an adjustment tank 12 for adjustment treatment, and a water pump 13, an electromagnetic flowmeter 14, and a grit chamber 15 for grit treatment. The water outlet of the grid tank 11 is communicated with the adjustment tank 12. The water pump 13 is installed in the adjustment tank 12. The water pump 13 pumps the liquid in the adjustment tank 12 to the grit chamber 15 through the electromagnetic flowmeter 14. The water outlet of the grit chamber 15 is communicated with the microbial treatment device 2. Among them, the grid tank 11: adopts a stepped coarse and fine grid (coarse grid gap 10mm, fine grid gap 3mm) to intercept suspended solids (such as plastics, fibers). The adjustment tank 12: is equipped with a liquid level sensor and a variable frequency water pump 13, and accurately controls the influent flow rate (error <±2%) through the electromagnetic flowmeter 14 to adjust the hydraulic retention time. The grit chamber 15: a vortex grit removal device (surface load 120m 3 / (m 2 ·h)) removes inorganic sand grains with a density > 2.65 g / cm 3 . Optionally, the inorganic sand grains precipitated in the grit chamber 15 can be further treated by a sand-water separator 16.

[0086] In this way, the grid treatment uses coarse and fine grids for hierarchical interception to remove suspended solids with a particle size > 5 mm in the sewage. The adjustment treatment balances the water quality and quantity through the hydraulic retention time (HRT = 4 - 6 h) to buffer the influent fluctuation. The grit treatment uses a vortex grit chamber to remove inorganic sand grains with a density > 2.65 g / cm 3 (such as quartz sand, metal chips). In addition, the precipitated inorganic sand grains can be further separated by a sand-water separator.

[0087] As Figures 9 to 11 shown, in step S02, the microbial treatment includes anaerobic treatment, anoxic treatment, and aerobic treatment.

[0088] The microbial treatment can be carried out by the microbial treatment device 2. The microbial treatment device 2 includes a first AHBBR pool 21 (anaerobic high-load biofilm reactor), a second AHBBR pool 22 (anoxic high-load biofilm reactor), an OHBBR pool 23 (aerobic high-load biofilm reactor), and microbial materials 24 respectively put into the first AHBBR pool 21, the second AHBBR pool 22, and the OHBBR pool 23. Among them, the microbial materials 24 include suspended packing, and the specific surface area of the suspended packing > 4000 m 2 / m 3 , which enriches the microbial flora and enriches the categories of the microbial flora. The suspended packing can be a polyurethane biomass-increasing sponge body (APG), and its specific surface area > 3000 m 2 / m 3, the hydrophilic sedimentation rate < 10 seconds. In some embodiments, the microbial material 24 further includes microbial strains (which may include nitrifying bacteria, denitrifying bacteria, and bacteria for decomposing refractory organic matter, and the strain density ≥ 5 billion CFU / g) and / or microbial enhancement plates and / or activity promoters. Optionally, the COD volume loading of the microbial treatment device 2 (the COD volume loading refers to the amount of COD (chemical oxygen demand) borne by a unit volume of the reactor per unit time, and it is an important indicator for measuring the treatment capacity and operation efficiency of the wastewater treatment system) is 6 - 10 kg / m 3 ·d, the denitrification efficiency is increased by 3 times, and the ammonia nitrogen loading is 1 kg / m 3 ·d, and the sludge concentration is 8000 - 12000 mg / L.

[0089] The microbial treatment device 2 further includes a circulation pump 211, a fourth overflow tank 212, and a second three-phase separator 213 installed in the first AHBBR tank 21. The second three-phase separator 213 stably separates the sewage into gas, liquid, and solid. The generated gas is methane, which can be used for power generation, and the solid precipitates. During this process, the circulation pump 211 can pump the sediment at the bottom to the middle of the first AHBBR tank 21, enabling the sediment at the bottom to act on the microbial material 24 and strengthening the degradation of the sludge by the microbial material 24. The upper clear liquid then overflows into the second AHBBR tank 22 through the fourth overflow tank 212. In addition, a mechanical stirring device can be installed in the first AHBBR tank 21 for mechanical stirring to enhance the degradation efficiency.

[0090] The microbial treatment device 2 further includes a stirrer 221, a second sludge concentration detector 222, and a fifth overflow tank 223 installed in the second AHBBR tank 22. Through the stirring of the stirrer 221, the mixing is strengthened for denitrification and nitrogen removal. The second sludge concentration detector 222 can detect the sludge concentration in the second AHBBR tank 22. The upper clear liquid then overflows into the OHBBR tank 23 through the fifth overflow tank 223.

[0091] The microbial treatment device 2 further includes a second aeration disk 231, a third sludge concentration detector 232, and a dissolved oxygen concentration detector 233 installed in the OHBBR tank 23. The blower 443 (multiple blowers 443 can be provided) also supplies gas to the second aeration disk 231, and the second aeration disk 231 realizes efficient oxygen transfer and mixing functions. The third sludge concentration detector 232 and the dissolved oxygen concentration detector 233 respectively detect the sludge concentration and the dissolved oxygen concentration in the OHBBR tank 23.

[0092] The microbial treatment device 2 further includes a second sludge reaction promoting mechanism 25, which can be installed in the first AHBBR tank 21 and / or the second AHBBR tank 22 and / or the OHBBR tank 23. Among them, the structure and principle of the second sludge reaction promoting mechanism 25 are the same as those of the first sludge reaction promoting mechanism, so they will not be repeated here. As Figure 3 and Figure 10 shown, the second sludge reaction promoting mechanism 25 is installed in the OHBBR tank 23.

[0093] The purpose of adopting the "AHBBR-OHBBR" sewage treatment process is to improve the sewage treatment efficiency and reduce the sludge volume (the sludge volume can be reduced by 30-50%).

[0094] In this way, through the "anaerobic-anoxic-aerobic" coupling process, the efficient removal of carbon, nitrogen, and phosphorus is realized synchronously (the TP removal rate > 80%), avoiding the limitations of a single treatment mode. In addition, the sludge production can be reduced. Specifically, the anaerobic section degrades macromolecular organic matter, reducing the amount of microbial proliferation in the subsequent aerobic section, and the sludge volume is reduced by 30%-50%.

[0095] As Figure 11 shown, a method for biodegradable sludge is specifically as follows:

[0096] After the sewage is intercepted by impurities in the grid tank 11, it enters the regulating tank 12 for homogenization and equalization, and then is pumped into the grit chamber 15 by the water pump 13 to separate inorganic sand particles. The precipitated inorganic sand particles can be further separated by the sand-water separator 16;

[0097] The sewage enters the first AHBBR tank 21, the second AHBBR tank 22, and the OHBBR tank 23 in sequence, and a biofilm is formed on the surface of the suspended packing to degrade COD, ammonia nitrogen, and total phosphorus;

[0098] The secondary sedimentation tank 3 separates the sludge and water by solid-liquid separation, and the purified water can be discharged or subjected to subsequent advanced treatment. The sludge is discharged to the sludge collection tank 41, and the sludge in the sludge collection tank 41 is quantitatively discharged into the anaerobic digestion tank 431 by the sludge pump 42 (the by-product biogas is used for power generation). The supernatant of the anaerobic digestion tank 431 flows to the aerobic digestion tank 441 by gravity. The aerobic digestion tank 441 is equipped with the first aeration disk 442. The mixed liquid of the aerobic digestion tank 441 overflows to the anoxic-oxic digestion tank 451, and the supernatant of the anoxic-oxic digestion tank 451 flows back to the first AHBBR tank. The above digestion reaction keeps the sludge in the state of extended aeration and self-degradation of the bacteria.

[0099] According to some embodiments of the present application, this embodiment also relates to a system for biodegradable sludge, which is used to execute the method for biodegradable sludge.

[0100] The technical solution of this application, a system for biodegradable sludge, can purify and precipitate the sludge in sewage, with a biodegradable sludge volume of 30%-50%, and further digest the precipitated sludge. The sludge reduction is achieved through extended aeration and microbial predation, with a biodegradable sludge volume of 50%-60%. Thus, the total sludge reduction can reach over 90% overall.

[0101] As Figure 12 shown, the system for biodegradable sludge also includes a PCL control system. The PCL control system is respectively communicatively connected to the pretreatment device 1, the microbial treatment device 2, the secondary sedimentation tank 3, and the digestion treatment device 4, and is under overall control through the PCL control system. Among them, the PCL control system can control the variable-frequency speed-regulating water pump, the aeration device, pH, dissolved oxygen, and sludge concentration (for example: controlling the sludge concentration to be maintained at 8000mg / L - 12000mg / L in the OHBBR tank 23), etc., and through fuzzy algorithms, edge computing nodes, and neural network algorithm models, realize real-time monitoring and adjustment of water quality parameters. Moreover, by combining fuzzy algorithms and neural network algorithm models, parameters such as aeration volume and reflux ratio can be dynamically adjusted, increasing the shock load resistance ability by 50%. Specifically, the PCL control system can adjust the aeration volume (0.1 - 0.3m 3 / min), the stirring speed (50 - 100rpm), real-time monitor COD, ammonia nitrogen, pH, and feedback to the neural network model to achieve the state of extended aeration and reduce sludge production. In some embodiments, the PLC control system is also equipped with a redundant network architecture and a remote operation and maintenance platform, supporting real-time fault prediction and 3D visualization monitoring, improving the system stability and response speed.

[0102] It should be noted that although the above embodiments have been described in this article, the patent protection scope of the present invention is not limited thereby. Therefore, based on the innovative concept of the present invention, any changes and modifications made to the embodiments described in this article, or equivalent structural or equivalent process transformations made using the content of the specification and drawings of the present invention, directly or indirectly applying the above technical solutions to other related technical fields, are all included in the patent protection scope of the present invention.

Claims

1. A method for biodegradable sludge, characterized in that Including: S01: Pretreat the sewage to remove large particulate impurities and inorganic sand grains in the sewage; S02: Perform microbial treatment on the pretreated sewage, and utilize the metabolic activities of microorganisms to degrade, transform or remove pollutants in the sewage to purify the sewage; S03: Perform sedimentation treatment on the purified sewage to precipitate the sludge to achieve the separation of sludge and water; S04: Perform digestion treatment on the precipitated sludge to keep the sludge in the state of extended aeration and self-degradation, and complete the sludge degradation.

2. The method for biodegradable sludge according to claim 1, characterized in that, In step S04, the digestion treatment includes sludge collection, anaerobic digestion treatment, aerobic digestion treatment and anoxic digestion treatment.

3. The method for biodegradable sludge according to claim 2, wherein The sludge collection is specifically that the precipitated sludge is collected through a sludge collection tank, and the sludge is quantitatively discharged through a sludge pump installed in the sludge collection tank.

4. The method for biodegradable sludge according to claim 3, characterized in that, The anaerobic digestion treatment is specifically that the sludge pump quantitatively discharges the sludge into an anaerobic digestion tank, and the sludge is stably separated into gas, liquid and solid by a first three-phase separator installed in the anaerobic digestion tank. The separated supernatant then flows out through a first overflow tank installed in the anaerobic digestion tank.

5. The method for biodegradable sludge according to claim 4, wherein, The aerobic digestion treatment is specifically that the separated upper liquid flows into an aerobic digestion tank through the first overflow tank, and a first aeration disk installed in the aerobic digestion tank efficiently and evenly disperses oxygen into the sewage to provide the required dissolved oxygen for microbial metabolism to promote the mixing and reaction of the supernatant. The upper mixed liquid then flows out through a second overflow tank installed in the aerobic digestion tank.

6. The method for biodegradable sludge according to claim 5, characterized in that, The anoxic digestion treatment is specifically that the upper mixed liquid flows into an anoxic digestion tank through the second overflow tank, and the anoxic digestion tank efficiently degrades the mixed liquid. The upper supernatant then flows out through a third overflow tank installed in the anoxic digestion tank.

7. The method for biodegradable sludge according to claim 1, wherein After step S04 "Perform digestion treatment on the precipitated sludge to keep the sludge in the state of extended aeration and self-degradation, and complete the sludge degradation", it further includes step S05: Return the digested sludge to step S02 again to perform microbial treatment together with the pretreated sewage.

8. The method for biodegradating sludge according to claim 1, wherein In step S01, the pretreatment includes grid treatment, conditioning treatment and grit removal treatment.

9. The method for biodegradable sludge according to claim 1, wherein In step S02, the microbial treatment includes anaerobic treatment, anoxic treatment and aerobic treatment.

10. A system for biodegradable sludge, characterized in that, A method for biologically degrading sludge as claimed in any one of claims 1-9.

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