Sludge anaerobic fermentation system and system operation control method

Abstract

The invention discloses a sludge anaerobic fermentation system and a system operation control method, and the sludge anaerobic fermentation system comprises a sludge pretreatment unit which is used for adding ozone microbubbles into a sludge mixed solution to obtain a pretreated sludge mixed solution, and conveying the pretreated sludge mixed solution to a sludge anaerobic fermentation unit; the sludge anaerobic fermentation unit is communicated with the sludge pretreatment unit and is used for performing anaerobic fermentation on the pretreated sludge mixed liquid. The ozone and the microbubbles are combined to form the ozone microbubbles, and the ozone microbubbles are utilized to pretreat the sludge, so that the oxidation efficacy of the ozone can be fully utilized, the damage of microbial cell walls and the decomposition of macromolecular organic matters are accelerated, the sludge hydrolysis rate is increased, and the anaerobic fermentation efficiency is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of sludge fermentation, and in particular to a sludge anaerobic fermentation system and a system operation control method. Background Art

[0002] At present, urban sewage treatment plants widely use the activated sludge process, which uses the metabolism of microorganisms to adsorb, assimilate, degrade and transform pollutants in water, thereby purifying sewage. As a product of sewage treatment, the activated sludge process will inevitably produce a large amount of residual sludge. If the residual sludge is not further treated, it will bring the risk of secondary pollution to the environment.

[0003] Residual sludge itself has the dual attributes of "resource" and "pollution". In order to promote the treatment and disposal of sludge, reduce the amount of sludge landfill, and realize the recycling of residual sludge resources and energy, sludge anaerobic fermentation and methane production and other resource reduction technologies have emerged. Specifically, anaerobic fermentation and methane production are usually based on three stages: hydrolysis, acid production, and methane production. However, in the existing anaerobic fermentation and methane production systems, the sludge hydrolysis rate is slow, which leads to low anaerobic fermentation efficiency.

[0004] Therefore, there is an urgent need for a sludge anaerobic fermentation system to solve the problem of low sludge anaerobic fermentation efficiency in the prior art. Summary of the invention

[0005] In view of this, the present invention provides a sludge anaerobic fermentation system and a system operation control method, the main purpose of which is to solve the current problem of low efficiency of sludge anaerobic fermentation.

[0006] In order to solve the above problems, the present application provides a sludge anaerobic fermentation system, comprising:

[0007] The sludge pretreatment unit is used to add ozone microbubbles to the sludge mixed liquid to obtain the sludge mixed liquid after oxidation pretreatment, and transport the pretreated sludge mixed liquid to the sludge anaerobic fermentation unit;

[0008] The sludge anaerobic fermentation unit is connected to the sludge pretreatment unit and is used for performing anaerobic fermentation on the pretreated sludge mixed liquid.

[0009] Optionally, the sludge anaerobic fermentation system further comprises: a filtering unit for pre-filtering the sludge mixed liquid, and the filtering unit specifically comprises:

[0010] A sludge cutter is arranged on the sludge conveying pipeline and is used for cutting impurities in the sludge mixed liquid;

[0011] The oscillating filter is arranged behind the sludge cutter and is used for filtering impurities in the sludge mixed liquid to obtain the filtered sludge mixed liquid.

[0012] Optionally, the sludge pretreatment unit comprises:

[0013] A sludge oxidation tank, used for oxidizing the sludge in the sludge mixed liquor in a continuous flow manner;

[0014] an ozone generator, used for supplying ozone to the sludge oxidation tank;

[0015] A microbubble disperser, used for generating microbubbles and adding them into the sludge oxidation tank;

[0016] A circulation pump is arranged outside the sludge oxidation tank, the liquid outlet of the circulation pump is connected with the liquid inlet of the jet mixer through a pipeline, and is used to extract the sludge mixed liquid in the sludge oxidation tank and transport the sludge mixed liquid to the jet mixer;

[0017] The jet mixer is arranged outside the sludge oxidation tank, and the air inlet of the jet mixer is connected to the air outlet of the ozone generator through a pipeline, so as to receive the ozone delivered by the ozone generator and mix the ozone with the sludge mixed liquid. The liquid outlet of the jet mixer is connected to the liquid inlet of the microbubble disperser through a pipeline, so as to deliver the sludge mixed liquid containing ozone to the microbubble disperser.

[0018] Optionally, the sludge pretreatment unit further includes: an ozone tail gas destroyer; the ozone tail gas destroyer is arranged outside the sludge oxidation tank, and is used to extract the tail gas from the top of the sludge oxidation tank through a pipeline, and destroy and decompose the ozone in the tail gas.

[0019] In order to solve the above problems, the present application provides a system operation control method, which is applied to any of the above-mentioned sludge anaerobic fermentation systems, and the method comprises:

[0020] Controlling the sludge pretreatment unit to add ozone microbubbles into the sludge mixed liquid to obtain a pretreated sludge mixed liquid;

[0021] The sludge anaerobic fermentation unit is controlled to perform anaerobic fermentation treatment on the pretreated sludge mixed liquid.

[0022] Optionally, before adding ozone microbubbles to the sludge mixed liquor, the method further comprises:

[0023] Controlling the moisture content of the sludge mixed liquor to achieve a target moisture content;

[0024] The target moisture content ranges from 96% to 98%.

[0025] Optionally, when controlling the ozone generator to add ozone to the sludge mixture, the ozone content at the outlet of the ozone generator is in the range of 50-150 g / Nm 3 ; The range of ozone dosage is 5g(O3) / Kg(absolutely dry sludge)-10g(O3) / Kg(absolutely dry sludge);

[0026] When the microbubble disperser is controlled to add ozone microbubbles into the sludge mixed liquid, the water inlet pressure range of the microbubble disperser is 0.15MPa-0.4MPa.

[0027] Optionally, the system operation control method also includes: controlling the sludge oxidation pond to operate in a continuous flow manner with a hydraulic retention time ranging from 5h to 7h.

[0028] Optionally, the system operation control method further includes:

[0029] The ratio of the circulation flow of the sludge oxidation tank to the sludge inlet flow of the sludge oxidation tank is controlled to be between 20:1 and 50:1.

[0030] The sludge anaerobic fermentation system and system operation control method in the present application, by combining ozone with microbubbles to form ozone microbubbles, uses ozone microbubbles to pre-treat the sludge, can fully utilize the oxidative effect of ozone, accelerate the destruction of microbial cell walls and the decomposition of macromolecular organic matter, increase the sludge hydrolysis rate, and thus improve the anaerobic fermentation efficiency. At the same time, the ozone dosage in the present application is low, the sludge pretreatment system is simple, and the operation is convenient.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0033] Figure 1 This is a schematic diagram of the system architecture of a sludge anaerobic fermentation system according to an embodiment of the present application;

[0034] Figure 2 This is a flow chart of a system operation control method according to another embodiment of the present application. DETAILED DESCRIPTION

[0035] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0036] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but only as an example of an embodiment. Other modifications within the scope and spirit of the present application will occur to those skilled in the art.

[0037] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0038] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0039] It should also be understood that although the present application has been described with reference to some specific examples, those skilled in the art will be able to readily implement many other equivalent forms of the present application.

[0040] The above and other aspects, features and advantages of the present application will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings.

[0041] Specific embodiments of the present application are described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments applied for are merely examples of the present application, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that obscure the present application. Therefore, the specific structural and functional details applied for herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present application in a variety of ways with substantially any suitable detailed structure.

[0042] This specification may use the phrases "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present application.

[0043] The present application embodiment provides a sludge anaerobic fermentation system, such as Figure 1As shown, the system in this embodiment includes: a filtering unit 1, a sludge pretreatment unit 2 and a sludge anaerobic fermentation unit 3. Among them, the filtering unit 1 is used to filter impurities in the sludge mixed liquor to avoid the problem of clogging and rapid wear caused by impurities in the subsequent sludge pretreatment unit when pretreating the sludge mixed liquor. In this embodiment, the sludge pretreatment unit 2 is used to add ozone microbubbles to the filtered sludge mixed liquor to obtain the sludge mixed liquor after oxidation pretreatment, and transport the pretreated sludge mixed liquor to the sludge anaerobic fermentation unit 3; the sludge anaerobic fermentation unit 3 is connected to the sludge pretreatment unit for anaerobic fermentation of the pretreated sludge mixed liquor. In the specific implementation process of this embodiment, the pretreated sludge mixed liquor is first deoxygenated, and then the deoxygenated sludge mixed liquor is transported to the sludge anaerobic fermentation unit.

[0044] The sludge anaerobic fermentation system in this embodiment combines ozone with microbubbles to form ozone microbubbles, and uses ozone microbubbles to pre-treat the sludge, which can fully utilize the oxidative effect of ozone, accelerate the destruction of microbial cell walls and the decomposition of macromolecular organic matter, increase the sludge hydrolysis rate, and thus improve the anaerobic fermentation efficiency. At the same time, in this application, the ozone dosage is low, the sludge pretreatment system is simple, and the operation is convenient.

[0045] On the basis of the above-mentioned embodiments, another embodiment of the present application provides a sludge anaerobic fermentation system. In this embodiment, the filtration unit specifically includes a sludge cutter and an oscillation filter. Specifically, the sludge cutter is arranged on the sludge conveying pipeline, and is used to cut and process the impurities in the sludge mixed liquid; the oscillation filter is arranged behind the sludge cutter, and is used to filter the impurities in the sludge mixed liquid in the filtration tank to obtain the filtered sludge mixed liquid. In this embodiment, the liquid outlet of the oscillation filter is connected to the sludge oxidation tank through a pipeline, and is used to convey the filtered sludge mixed liquid to the sludge oxidation tank.

[0046] In this embodiment, the sludge pretreatment unit specifically includes: a sludge oxidation tank, an ozone generator, a microbubble disperser, a circulation pump and a jet mixer.

[0047] Among them, the sludge oxidation tank is used to oxidize the sludge in the sludge mixed liquor in a continuous flow manner, that is, the sludge mixed liquor flows into the sludge oxidation tank through the mud inlet, and is oxidized to obtain the pretreated sludge mixed liquor, and the pretreated sludge mixed liquor flows out of the sludge oxidation tank through the mud outlet.

[0048] The circulation pump is arranged outside the sludge oxidation tank, and the water inlet of the circulation pump is connected to the bottom of the sludge oxidation tank through a pipeline. The liquid outlet of the circulation pump is connected to the liquid inlet of the jet mixer through a pipeline, so as to extract the sludge mixed liquid in the sludge oxidation tank and transport the sludge mixed liquid to the jet mixer.

[0049] The jet mixer is arranged outside the sludge oxidation tank, and the air inlet of the jet mixer is connected to the air outlet of the ozone generator through a pipeline, which is used to receive the ozone delivered by the ozone generator and mix the ozone with the sludge mixed liquid. The liquid outlet of the jet mixer is connected to the liquid inlet of the microbubble disperser through a pipeline, which is used to deliver the sludge mixed liquid containing ozone to the microbubble disperser, so that the microbubble disperser can form ozone microbubbles based on ozone and disperse the ozone microbubbles into the sludge mixed liquid. In this embodiment, the sludge pretreatment unit also includes an ozone tail gas destroyer, which is arranged outside the oxidation tank, extracts the tail gas from the top of the sludge oxidation tank through a pipeline, and destroys and decomposes the ozone in the tail gas.

[0050] The sludge anaerobic fermentation system in this embodiment combines ozone with microbubbles to form ozone microbubbles, and uses ozone microbubbles to pretreat the sludge, which can effectively improve the utilization efficiency of ozone and the decomposition rate of sludge, thereby improving the efficiency of anaerobic fermentation of sludge. The ozone dosage of the present invention is low, the sludge pretreatment system is simple, the operation is convenient, and it has strong practical value.

[0051] Another embodiment of the present application provides a system operation control method, such as Figure 2 As shown, applied to any of the above-mentioned sludge anaerobic fermentation systems, the method comprises:

[0052] Step S101, controlling the sludge pretreatment unit to add ozone microbubbles into the sludge mixed solution to obtain the sludge mixed solution after oxidation pretreatment;

[0053] Step S102, controlling the sludge anaerobic fermentation unit to perform anaerobic fermentation treatment on the pretreated sludge mixed liquid.

[0054] In this embodiment, before adding ozone microbubbles to the sludge mixture, the method further includes: controlling the moisture content of the sludge mixture to achieve a target moisture content; the target moisture content ranges from 96% to 98%. When controlling the ozone generator to add ozone to the sludge mixture, the ozone content at the outlet of the ozone generator ranges from 50 to 150 g / Nm 3 ; The range of ozone dosage is 5g(O3) / Kg (absolutely dry sludge)-10g(O3) / Kg (absolutely dry sludge); when controlling the microbubble disperser to add ozone microbubbles to the sludge mixture, the water pressure range of the microbubble disperser is 0.15MPa-0.4MPa. In this embodiment, by controlling the ozone content and the dosage of ozone, the addition of ozone can be made more reasonable and accurate, and the rapid hydrolysis of sludge is ensured while avoiding ozone waste, which lays a foundation for improving the efficiency of anaerobic fermentation of sludge.

[0055] The system operation control method in this embodiment also includes controlling the sludge oxidation tank to operate in a continuous flow mode, and the hydraulic retention time ranges from 5h to 7h. In this embodiment, by controlling the hydraulic retention time, the ozone microbubbles and the sludge mixed liquid can be mixed more fully and evenly, ensuring sufficient oxidation time, which lays the foundation for subsequent acceleration of sludge hydrolysis and improvement of sludge anaerobic fermentation efficiency.

[0056] The system operation control method in this embodiment further includes: controlling the ratio of the circulation flow of the sludge oxidation tank to the sludge inlet flow of the sludge oxidation tank to be between 20:1 and 50:1. In this embodiment, by controlling the ratio of the circulation flow of the circulation pump to the sludge inlet flow of the sludge oxidation tank, the ozone microbubbles and the sludge mixed liquid can be mixed more fully and evenly, ensuring the formation effect of the microbubbles, and laying a foundation for subsequently accelerating the hydrolysis of the sludge in the sludge mixed liquid and improving the anaerobic fermentation efficiency of the sludge.

[0057] That is, in this embodiment, before adding ozone microbubbles to the sludge mixed liquid, the water content of the sludge mixed liquid can be controlled to control the water content of the sludge mixed liquid to 96-98%. The sludge mixed liquid is then transported to the sludge cutter through a pipeline to cut the impurities in the sludge mixed liquid; and the impurities in the sludge mixed liquid are filtered through an oscillating filter to obtain the filtered sludge mixed liquid, and the filtered sludge mixed liquid is transported to the sludge oxidation tank, and the sludge oxidation tank is controlled to operate in a continuous flow mode, and the corresponding hydraulic retention time is controlled to be 5-7h. The circulating pump at the bottom of the sludge oxidation tank is controlled to extract the sludge mixed liquid in the sludge oxidation tank, and the sludge mixed liquid after passing through the jet mixer and the microbubble disperser in turn returns to the sludge oxidation tank, completing the circulation of the mixed liquid and the formation and release of ozone microbubbles. The ratio of the circulating flow rate of the sludge mixed liquid extracted by the circulating pump to the sludge inlet flow rate of the sludge oxidation tank is controlled to be between 20:1 and 50:1, and the water pressure of the micro-bubble disperser is controlled to be between 0.15-0.4MPa. In the specific implementation process of this embodiment, the ozone content of the ozone generator outlet gas can also be controlled to be between 50-150g / Nm 3, the ozone dosage is controlled at 5-10g (O3) / Kg (absolutely dry sludge) (that is, the ozone dosage corresponding to each kilogram of absolutely dry sludge is between 5 grams and 10g), and the amount of ozone introduced into the system can also be dynamically regulated according to the amount of sludge entering the sludge oxidation tank. Finally, the sludge mixture after ozone microbubble pretreatment enters the sludge anaerobic fermentation treatment unit. In this embodiment, after obtaining the pretreated sludge mixture, the pretreated sludge mixture can be first deoxygenated, and then the deoxygenated sludge mixture is mixed with the digested sludge in a predetermined ratio to obtain a target sludge mixture, and then the target sludge mixture is anaerobically fermented to generate methane after a predetermined fermentation time.

[0058] In the following, a sludge anaerobic fermentation system of the present application is used to carry out sludge anaerobic fermentation experiments. The sludge anaerobic fermentation system described in this embodiment is as follows: Figure 1 As shown, it includes: 1. filtration unit; 2. sludge pretreatment unit; 3. sludge anaerobic fermentation unit.

[0059] Experiment 1:

[0060] Specifically, the sludge used in the experiment was the residual sludge from the sludge thickening tank of a sewage treatment plant. The main indicators of the sludge were as follows: the sludge moisture content was 97.5%; the proportion of organic components in the sludge was 63%.

[0061] The remaining sludge first enters the sludge filtration unit through the pipeline to remove large particles of inorganic matter, hair and other impurities; then the sludge mixed liquid enters the sludge oxidation tank through the pipeline, and the sludge pretreatment is completed under the action of ozone microbubbles. The sludge oxidation tank operates in a continuous flow mode, and the hydraulic retention time is controlled at 7h; the circulating pump extracts the mixed liquid in the sludge oxidation tank, and the mixed liquid returns to the sludge oxidation tank after passing through the jet mixer and the microbubble disperser in turn, completing the circulation of the mixed liquid and the formation and release of ozone microbubbles. The ratio of the circulation flow rate to the sludge flow rate into the sludge oxidation tank is controlled at 40:1, and the water pressure entering the microbubble disperser is controlled at 0.20MPa; the ozone content of the ozone generator outlet gas is controlled at 110g / Nm 3 The ozone dosage was controlled at 8g(O3) / Kg (absolutely dry sludge). The pretreated sludge mixture was deoxygenated, and then 100ml of the deoxygenated sludge mixture was mixed with 300ml of digested sludge for anaerobic fermentation. After one fermentation cycle, the amount of methane produced was measured to be 440ml.

[0062] Experiment 2:

[0063] The sludge used in the experiment was the residual sludge from the sludge thickening tank of a sewage treatment plant. The main indicators of the sludge were as follows: the sludge moisture content was 97.5%; the proportion of organic components in the sludge was 63%.

[0064] The remaining sludge first enters the sludge filtration unit through the pipeline to remove large particles of inorganic matter, hair and other impurities; then the sludge mixed liquid enters the sludge oxidation tank through the pipeline, and the sludge pretreatment is completed under the action of ozone microbubbles. The sludge oxidation tank operates in a continuous flow mode, and the hydraulic retention time is controlled at 5h; the circulating pump extracts the mixed liquid in the sludge oxidation tank, and the mixed liquid returns to the sludge oxidation tank after passing through the jet mixer and the microbubble disperser in turn, completing the circulation of the mixed liquid and the formation and release of ozone microbubbles. The ratio of the circulation flow rate to the sludge flow rate into the sludge oxidation tank is controlled at 40:1, and the water pressure entering the microbubble disperser is controlled at 0.20MPa; the ozone content of the ozone generator outlet gas is controlled at 110g / Nm 3 The ozone dosage was controlled at 8g(O3) / Kg (absolutely dry sludge). The pretreated sludge mixture was deoxygenated, and then 100ml of the deoxygenated sludge mixture was mixed with 300ml of digested sludge for anaerobic fermentation. After one fermentation cycle, the amount of methane produced was measured to be 390ml.

[0065] Experiment 3:

[0066] The test sludge is the residual sludge from the sludge thickening tank of a sewage treatment plant. The main indicators of the sludge are as follows: the sludge moisture content is 97.5%; the proportion of organic components in the sludge is 63%. Figure 1 shown.

[0067] The remaining sludge first enters the sludge filtration unit through the pipeline to remove large particles of inorganic matter, hair and other impurities; then the sludge mixed liquid enters the sludge oxidation tank through the pipeline, and the sludge pretreatment is completed under the action of ozone microbubbles. The sludge oxidation tank operates in a continuous flow mode, and the hydraulic retention time is controlled at 7h; the circulating pump extracts the mixed liquid in the sludge oxidation tank, and the mixed liquid returns to the sludge oxidation tank after passing through the jet mixer and the microbubble disperser in turn, completing the circulation of the mixed liquid and the formation and release of ozone microbubbles. The ratio of the circulation flow rate to the sludge flow rate into the sludge oxidation tank is controlled at 20:1, and the water pressure entering the microbubble disperser is controlled at 0.10MPa; the ozone content of the ozone generator outlet gas is controlled at 110g / Nm 3 The ozone dosage was controlled at 8g(O3) / Kg (absolutely dry sludge). The pretreated sludge mixture was deoxygenated, and then 100ml of the deoxygenated sludge mixture was mixed with 300ml of the same digested sludge as in the above embodiment for anaerobic fermentation. After one fermentation cycle, the amount of methane produced was measured to be 283ml.

[0068] Experiment 4:

[0069] The sludge used in the experiment was the residual sludge from the sludge thickening tank of a sewage treatment plant. The main indicators of the sludge were as follows: the sludge moisture content was 97.5%; the proportion of organic components in the sludge was 63%.

[0070] 100 ml of the test sludge mixture that had not been pretreated with ozone microbubbles was taken and mixed with 300 ml of the deoxygenated digested sludge that was the same as in the above example for anaerobic fermentation. After one fermentation cycle, the amount of methane produced was measured to be 180 ml.

[0071] By comparing the above-mentioned sludge anaerobic fermentation experiments 1 and 2 with experiments 3 and 4, it can be seen that the use of the sludge anaerobic fermentation system of the present application and the anaerobic fermentation treatment of sludge according to the system operation control method of the present application can increase the output of methane. Therefore, the sludge anaerobic fermentation system and the system operation control method in the present application can improve the efficiency of sludge anaerobic fermentation.

[0072] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. A sludge anaerobic fermentation system, characterized in that: include: The sludge pretreatment unit is used to add ozone microbubbles to the sludge mixed liquid to obtain the sludge mixed liquid after oxidation pretreatment, and transport the pretreated sludge mixed liquid to the sludge anaerobic fermentation unit; The sludge anaerobic fermentation unit is connected to the sludge pretreatment unit and is used for performing anaerobic fermentation on the pretreated sludge mixed liquid.

2. The system according to claim 1, characterized in that The system further comprises: a filtering unit for pre-filtering the sludge mixed liquid, wherein the filtering unit specifically comprises: A sludge cutter is arranged on the sludge conveying pipeline and is used for cutting impurities in the sludge mixed liquid; The oscillating filter is arranged behind the sludge cutter and is used for filtering impurities in the sludge mixed liquid to obtain the filtered sludge mixed liquid.

3. The system according to claim 1, characterized in that The sludge pretreatment unit comprises: A sludge oxidation tank, used for oxidizing the sludge in the sludge mixed liquor in a continuous flow manner; an ozone generator, used for supplying ozone to the sludge oxidation tank; A microbubble disperser, used for generating ozone microbubbles and adding them into the sludge oxidation tank; A circulation pump is arranged outside the sludge oxidation tank, the liquid outlet of the circulation pump is connected with the liquid inlet of the jet mixer through a pipeline, and is used to extract the sludge mixed liquid in the sludge oxidation tank and transport the sludge mixed liquid to the jet mixer; The jet mixer is arranged outside the sludge oxidation tank, and the air inlet of the jet mixer is connected to the air outlet of the ozone generator through a pipeline, which is used to receive the ozone generated by the ozone generator and mix the ozone with the sludge mixed liquid. The liquid outlet of the jet mixer is connected to the liquid inlet of the microbubble disperser through a pipeline, which is used to transport the sludge mixed liquid containing ozone to the microbubble disperser.

4. The system according to claim 3, characterized in that The sludge pretreatment unit also includes: an ozone tail gas destroyer; The ozone tail gas destroyer is arranged outside the sludge oxidation tank, and is used to extract the tail gas from the top of the sludge oxidation tank through a pipeline, and destroy and decompose the ozone in the tail gas.

5. A system operation control method, characterized in that: Applied to the sludge anaerobic fermentation system according to any one of claims 1 to 5, the method comprises: Controlling the sludge pretreatment unit to add ozone microbubbles into the sludge mixed liquid to obtain a pretreated sludge mixed liquid; The sludge anaerobic fermentation unit is controlled to perform anaerobic fermentation treatment on the pretreated sludge mixed liquid.

6. The method according to claim 5, characterized in that Before adding ozone microbubbles to the sludge mixed liquor, the method further comprises: Controlling the moisture content of the sludge mixed liquor to achieve a target moisture content; The target moisture content ranges from 96% to 98%.

7. The method according to claim 5, characterized in that When controlling the ozone generator to add ozone to the sludge mixture, the ozone content at the outlet of the ozone generator ranges from 50 to 150 g / Nm 3 ; The range of ozone dosage is 5g(O3) / Kg(absolutely dry sludge)-10g(O3) / Kg(absolutely dry sludge); When the microbubble disperser is controlled to add ozone microbubbles into the sludge mixed liquid, the water inlet pressure range of the microbubble disperser is 0.15MPa-0.4MPa.

8. The method according to claim 5, characterized in that The method further comprises: controlling the sludge oxidation pond to operate in a continuous flow mode, with a hydraulic retention time ranging from 5h to 7h.

9. The method according to claim 5, characterized in that The method further comprises: The ratio of the circulation flow of the sludge oxidation tank to the sludge inlet flow of the sludge oxidation tank is controlled to be between 20:1 and 50:1.

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