A double-track urban sewage treatment method and device, electronic equipment and storage medium

Abstract

The present application relates to the technical field of water treatment, and particularly relates to a double-track urban sewage treatment method and device, electronic equipment and storage medium, the method is applied to the control unit of the double-track urban sewage treatment system; the method comprises the following steps: obtaining an ammonia nitrogen concentration value of effluent; according to a comparison relationship between the ammonia nitrogen concentration value and a preset threshold value, controlling the double-track urban sewage treatment system to operate in a target mode. The present application firstly obtains the ammonia nitrogen concentration value of effluent, and adjusts the target mode operation of the double-track urban sewage treatment system according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, so that the operation mode is adjusted according to different situations, and the sewage treatment efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water treatment, and in particular to a double-track urban sewage treatment method and device, an electronic device and a storage medium. BACKGROUND

[0002] The nitrification-denitrification process of the traditional activated sludge method has good effect on nitrogen removal, but the nitrification reaction needs to remove organic matter and ammonia nitrogen in water in turn, and needs a long hydraulic retention time and a larger reactor volume, which increases the construction investment, and the denitrification needs sufficient organic matter, and needs to add external carbon source in the nitrification reaction effluent, which increases the operation cost, so that the process does not reasonably utilize the carbon source in the sewage, resulting in long operation time, high construction and operation cost (including aeration energy consumption, external carbon source, etc.); at the same time, the continuous flow operation of nitrification and denitrification may promote the growth of filamentous bacteria, increase the risk of sludge bulking, and affect the settling performance of activated sludge and the stability of the system. In addition, the system has poor adaptability to impact load, and when the water quality or water quantity fluctuates greatly, the denitrification effect is easily affected, which may lead to total nitrogen (TN) exceeding the standard. It is urgent to research and improve the process to improve the efficiency and reduce the cost. SUMMARY

[0003] Therefore, the present application aims to provide a double-track urban sewage treatment method and device, an electronic device and a storage medium.

[0004] In a first aspect, the present application provides a double-track urban sewage treatment method applied to a control unit of a double-track urban sewage treatment system; the double-track urban sewage treatment system further comprises an aerobic unit, a secondary sedimentation tank, a regulating tank, an anoxic tank and a chemical phosphorus removal unit connected in sequence, and an input end of the aerobic unit is connected with a sewage source; the control unit is connected with a double-track working tank in the aerobic unit, and by adjusting the working parameters of the double-track working tank in the aerobic unit, the double-track working tank is operated in a high-speed activated sludge tank mode or a nitrification tank mode, so as to adjust the working mode of the double-track urban sewage treatment system; the method comprises:

[0005] obtaining an ammonia nitrogen concentration value of the effluent;

[0006] According to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, the double-track urban sewage treatment system is controlled to operate in a target mode.

[0007] In combination with the first aspect, according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, the step of controlling the double-track urban sewage treatment system to operate in a target mode comprises:

[0008] If the ammonia nitrogen concentration value is less than the preset threshold value, the double-track urban sewage treatment system is controlled to operate in a first mode;

[0009] If the ammonia nitrogen concentration value is greater than or equal to the preset threshold value, the double-track urban sewage treatment system is controlled to operate in the second mode, and is switched to operate in the first mode after a preset time length.

[0010] In combination with the first aspect, the step of controlling the double-track urban sewage treatment system to operate in the first mode includes:

[0011] The double-track working pool in the aerobic unit is controlled to operate in the nitrification pool mode, and the pipeline connection between the wastewater source and the adjusting pool and the pipeline connection between the iron salt storage device and the mixing pool in the chemical phosphorus removal unit are turned on.

[0012] In combination with the first aspect, after the step of controlling the double-track working pool in the aerobic unit to operate in the nitrification pool mode and turning on the pipeline connection between the wastewater source and the adjusting pool and the pipeline connection between the iron salt storage device and the mixing pool in the chemical phosphorus removal unit, the step further includes:

[0013] The urban sewage is passed into the high-speed activated sludge pool with a dissolved oxygen concentration of 0.2-1 mg / L, and is preliminarily purified by controlling the sludge retention time to be 0.2-0.6 d and the hydraulic retention time to be 0.25-0.5 h, and then is passed into the nitrification pool for nitrification treatment;

[0014] The sludge-water mixture after the nitrification treatment is passed into the secondary sedimentation tank for separation, and the supernatant is transported to the adjusting pool to be mixed with the urban sewage, so as to adjust the mixed liquid to have a target nitrogen substrate ratio and a first target pH;

[0015] The mixed liquid with the target nitrogen substrate ratio and the first target pH is passed into the anoxic pool for short-range nitrate dissimilatory reduction to ammonium coupled with anaerobic ammonia oxidation reaction, to obtain a mixed liquid with removed nitrogen elements;

[0016] The mixed liquid with removed nitrogen elements is mixed with iron salt to a target iron-phosphorus ratio, and is subjected to phosphorus removal treatment, to obtain a target effluent.

[0017] In combination with the first aspect, the step of controlling the double-track urban sewage treatment system to operate in the second mode includes:

[0018] The double-track working pool in the aerobic unit is controlled to operate in the high-speed activated sludge pool mode, and the pipeline connection between the iron salt storage device and the adjusting pool and the mixing pool is turned on.

[0019] In combination with the first aspect, after the step of controlling the double-track working pool in the aerobic unit to operate in the high-speed activated sludge pool mode and turning on the pipeline connection between the iron salt storage device and the adjusting pool and the mixing pool, the step further includes:

[0020] The urban sewage is passed into two high-speed activated sludge pools connected in sequence, and for each high-speed activated sludge pool, the dissolved oxygen concentration is controlled to be 0.2-1 mg / L, the sludge retention time is controlled to be 0.1-0.3 d, and the hydraulic retention time is controlled to be 0.125-0.25 h for preliminary purification.

[0021] The preliminarily purified sludge-water mixture is introduced into a secondary sedimentation tank for separation, and the supernatant is transported to a conditioning tank to be mixed with a ferric salt to adjust the mixture to a target iron-nitrogen ratio and a second target pH;

[0022] The mixture with the target iron-nitrogen ratio and the second target pH is introduced into an anoxic tank for a ferric-type ANAMMOX reaction to obtain a nitrogen-removed mixture;

[0023] The nitrogen-removed mixture is mixed with the ferric salt to a target iron-phosphorus ratio for phosphorus removal treatment to obtain a target effluent.

[0024] In combination with the first aspect, according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, the step of controlling the dual-track municipal sewage treatment system to operate in the target mode further includes: turning on the pipeline connection between the dual-track municipal sewage treatment system and the sludge digestion system.

[0025] In the second aspect, the present application further provides a dual-track municipal sewage treatment device applied to a control unit of a dual-track municipal sewage treatment system; the dual-track municipal sewage treatment system further includes an aerobic unit, a secondary sedimentation tank, a conditioning tank, an anoxic tank and a chemical phosphorus removal unit connected in sequence, and an input end of the aerobic unit is connected with a sewage source; the control unit is connected with a dual-track working tank in the aerobic unit, and by adjusting the working parameters of the dual-track working tank in the aerobic unit, the dual-track working tank is controlled to operate in a high-speed activated sludge tank mode or a nitrification tank mode to adjust the working mode of the dual-track municipal sewage treatment system; the device includes:

[0026] The acquisition module is configured to acquire an ammonia nitrogen concentration value of the effluent.

[0027] The control module is configured to control the dual-track municipal sewage treatment system to operate in a target mode according to a comparison relationship between the ammonia nitrogen concentration value and a preset threshold value.

[0028] In the third aspect, the present application provides an electronic device including a memory and a processor, the memory is configured to store a computer program, and the processor is configured to run the computer program to enable the electronic device to execute the above-mentioned method.

[0029] In the fourth aspect, the present application provides a storage medium having computer program instructions stored therein, and the computer program instructions are read and run by a processor to execute the above-mentioned method.

[0030] The embodiment of the present application brings the following beneficial effects: the embodiment of the present application provides a double-track urban sewage treatment method, which is applied to a control unit of a double-track urban sewage treatment system; the double-track urban sewage treatment system further comprises an aerobic unit, a secondary sedimentation tank, a regulating tank, an anoxic tank and a chemical phosphorus removal unit connected in sequence, and an input end of the aerobic unit is connected with a sewage source; the control unit is connected with a double-track working tank in the aerobic unit, and by adjusting the working parameters of the double-track working tank in the aerobic unit, the double-track working tank is operated in a high-speed activated sludge tank mode or a nitrification tank mode, so as to adjust the working mode of the double-track urban sewage treatment system; the method comprises the following steps: obtaining an ammonia nitrogen concentration value of effluent; and according to a comparison relationship between the ammonia nitrogen concentration value and a preset threshold value, controlling the double-track urban sewage treatment system to operate in a target mode. The ammonia nitrogen concentration value of the effluent is obtained first, and then the target mode operation of the double-track urban sewage treatment system is adjusted according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, so that the operation mode is adjusted according to different situations, and the sewage treatment efficiency is improved.

[0031] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and achieved by the structure particularly pointed out in the description, claims and drawings.

[0032] In order to make the above-mentioned objects, characteristics and advantages of the present application more obvious and easy to understand, the following preferred embodiments are specifically described below, and the accompanying drawings are described in detail as follows. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0034] Figure 1 The double-track urban sewage treatment method flowchart provided by the embodiment of the present application is shown in the figure;

[0035] Figure 2 is a working principle schematic diagram of the double-track urban sewage treatment system in the first mode provided by the embodiment of the present application;

[0036] Figure 3 is a working principle schematic diagram of the double-track urban sewage treatment system in the second mode provided by the embodiment of the present application;

[0037] Figure 4 The double-track urban sewage treatment method device structure schematic diagram provided by the embodiment of the present application is shown in the figure;

[0038] Figure 5 An electronic device structure schematic diagram provided for an embodiment of the present application.

[0039] Reference signs:

[0040] 10 - acquisition module, 20 - control module;

[0041] 130 - processor, 131 - memory, 132 - bus, 133 - communication interface. DETAILED DESCRIPTION

[0042] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the present application will be described below in connection with the drawings, obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0043] To facilitate the understanding of the present embodiment, the application scenario and design idea of the present application embodiment will be briefly introduced first.

[0044] The nitrification-denitrification process of the traditional activated sludge method has good effect in denitrification, but the operation time of the process is long, the construction and operation cost is high, and the adaptability to impact load is poor. When the water quality or water quantity fluctuates greatly, the denitrification effect is easily affected, which may lead to the total nitrogen (TN) of the effluent exceeding the standard.

[0045] Based on this, the present application provides a double-track urban sewage treatment method and device, and an electronic device and a storage medium.

[0046] Embodiment 1

[0047] The present application provides a double-track urban sewage treatment method, which is applied to a control unit of a double-track urban sewage treatment system. The double-track urban sewage treatment system further comprises an aerobic unit, a secondary sedimentation tank, a regulating tank, an anoxic tank and a chemical phosphorus removal unit connected in sequence, and the input end of the aerobic unit is connected with a sewage source. The control unit is connected with a double-track working tank in the aerobic unit, and by adjusting the working parameters of the double-track working tank in the aerobic unit, the double-track working tank is operated in a high-speed activated sludge tank mode or a nitrification tank mode, so as to adjust the working mode of the double-track urban sewage treatment system. In combination Figure 1 As shown in the figure, the method comprises:

[0048] S110, acquiring an ammonia nitrogen concentration value of the effluent.

[0049] S120, according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, controlling the double-track urban sewage treatment system to operate in a target mode.

[0050] In the embodiment, the preset threshold value ranges from 1 mg / L to 4 mg / L. In actual operation, the water plant can flexibly adjust the preset threshold value according to actual conditions (such as effluent standards, monitoring frequency, and the like), and the preset threshold value is only an example and is not limited.

[0051] The double-track urban sewage treatment method provided in the application first acquires the ammonia nitrogen concentration value of the effluent, and adjusts the target mode operation of the double-track urban sewage treatment system according to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, so as to adjust the operation mode according to different influent conditions and improve the sewage treatment efficiency.

[0052] In combination with the first aspect, step S120 comprises:

[0053] S121, if the ammonia nitrogen concentration value is less than the preset threshold value, controlling the double-track urban sewage treatment system to operate in the first mode.

[0054] S122, if the ammonia nitrogen concentration value is greater than or equal to the preset threshold value, controlling the double-track urban sewage treatment system to operate in the second mode and switching to the first mode after a preset time length.

[0055] In the embodiment, the preset time length ranges from 7 days to 30 days. In actual operation, the water plant can flexibly adjust the preset time length according to actual conditions (such as sludge form, influent conditions, and the like). The preset time length is only an example and is not limited.

[0056] If the ammonia nitrogen concentration value of the effluent after sewage purification is not less than the preset threshold value, it indicates that the carbon-nitrogen ratio of the influent is low and the effective iron storage of the anoxic tank is insufficient, which means that the current operation condition cannot meet the purification requirement, resulting in a high ammonia nitrogen concentration in the effluent. At this time, the operation mode needs to be adjusted, and the iron cycle is re-introduced into the sewage treatment system to strengthen and assist the microbial metabolism.

[0057] In combination with the first aspect, the step of controlling the double-track urban sewage treatment system to operate in the first mode in step S121 comprises:

[0058] S1210, controlling the double-track working tank in the aerobic unit to operate in the nitrification tank mode, and turning on the pipeline connection between the sewage source and the adjusting tank, and the pipeline connection between the iron salt storage device and the mixing tank in the chemical phosphorus removal unit.

[0059] At this time, part of the sewage output from the sewage source directly enters the adjusting tank, and the remaining sewage enters the high-speed activated sludge tank. By shunting (the proportion can be adjusted) the sewage, the organic carbon source in the urban sewage can be reasonably utilized, and the aeration energy consumption can be reduced. Specifically, in combination with the first aspect, Figure 2As shown, at this time, the dual-track working pool is operated in the nitrification pool mode, and the high-rate activated sludge pool transfers organic matter from the sewage into the sludge, effectively reducing the organic load of the subsequent dual-track working pool operated in the nitrification pool mode, improving the nitrification reaction rate and reducing the aeration energy consumption; at the same time, the pipeline connection between the sewage and the adjusting pool is turned on, which can provide substrate ammonia nitrogen and organic carbon source for the subsequent biological reaction of anammox bacteria, reducing the demand for additional carbon source.

[0060] In combination with the first aspect, after step S1210, the method further includes:

[0061] S1211, the municipal sewage is introduced into the high-rate activated sludge pool with a dissolved oxygen concentration of 0.2-1 mg / L, and the sludge retention time is controlled to be 0.2-0.6 d and the hydraulic retention time is controlled to be 0.25-0.5 h for preliminary purification, and then introduced into the nitrification pool for nitrification treatment.

[0062] The high-rate activated sludge (HRAS) realizes rapid carbon removal and simultaneous energy recovery by reducing the sludge age of the system, which is specifically reflected in the operating parameters: dissolved oxygen (DO) concentration: 0.2-1 mg / L, sludge retention time (SRT): 0.2-0.6 days, hydraulic retention time (HRT): 0.25-0.5 hours. The high-rate activated sludge pool can quickly adsorb organic matter and store carbon source, providing low organic load conditions for subsequent nitrification reaction, improving the nitrification reaction rate and reducing the aeration energy consumption.

[0063] The nitrification reaction in the nitrification pool converts ammonia nitrogen (NH4 + -N) into nitrite nitrogen (NO2 - -N), and further into nitrate nitrogen (NO3 - -N), and the end dissolved oxygen (DO) is controlled to be 2-4 mg / L, and the ammonia nitrogen concentration is reduced to <0.5 mg / L, to ensure the oxidation of ammonia nitrogen to nitrate nitrogen.

[0064] S1212, the sludge-water mixture after nitrification treatment is introduced into the secondary sedimentation tank for separation, and the supernatant is transported to the adjusting tank to be mixed with the municipal sewage, so as to adjust the mixed liquid to the target nitrogen substrate ratio and the first target pH.

[0065] The supernatant of the secondary sedimentation tank enters the adjusting tank and is mixed with the sewage in a certain proportion, and the target nitrogen substrate ratio (NO3 - -N:NH4 + -N=1:1-1.32:1) is controlled to be 7.27-7.29, and at the same time, the sludge is backflowed to the high-rate activated sludge pool to maintain the sludge concentration (1500-3000 mg / L) in the aerobic zone.

[0066] In addition, the secondary sedimentation tank is arranged between the aerobic zone (O section) and the anoxic zone (A section), which is significantly different from the conventional process of arranging the secondary sedimentation tank at the end of the process. The secondary sedimentation tank can block the sludge circulation between the aerobic zone and the anoxic zone, reduce the risk of sludge bulking in the aerobic zone, and ensure the stability of the microbial flora structure in the anoxic zone.

[0067] S1213, the mixed liquor with the target nitrogen substrate ratio and the first target pH is introduced into the anoxic tank to perform a short-range nitrate dissimilation reduction to ammonium coupled with anaerobic ammonia oxidation reaction, so as to obtain a mixed liquor in which nitrogen elements are removed.

[0068] The anoxic zone is filled with anaerobic ammonium oxidation (Anammox) biofilm filler or granular sludge, and a partial dissimilatory nitrate reduction to ammonium (PDNRA) coupled with anaerobic ammonia oxidation (PDNRA-Anammox) reaction occurs in the anoxic zone.

[0069] In the process, the anaerobic ammonium oxidation bacteria can utilize the organic matter in the wastewater and the ferrous iron (Fe 2+ ) accumulated in the anoxic tank during the mode two operation as a complementary reducing agent to cooperatively drive the PDNRA reaction to proceed fully, thereby ensuring the smooth completion of the subsequent Anammox reaction and stabilizing the ammonia nitrogen concentration in the effluent to meet the standard.

[0070] When the influent condition is good and the carbon-nitrogen ratio is appropriate (C / N = 1.14-2.86), the PDNRA reaction can use the organic matter in the wastewater as a reducing agent, which can be represented as:

[0071] NO3 - + organic matter → NO2 - + CO2;

[0072] When the influent carbon source is insufficient, the PDNRA reaction can also use the ferrous iron (Fe 2+ ) accumulated in the anoxic tank during the mode two operation as a complementary reducing agent to ensure that the nitrate nitrogen is completely converted, which can be represented as:

[0073] NO3 - + Fe 2+ → NO2 - + Fe 3+ ;

[0074] The Anammox reaction can be represented as:

[0075] NH4 + + NO2 - → N2 + H2O.

[0076] In addition, the PDNRA-Anammox process also has significant advantages: not only can save carbon source, and without complex microbial community regulation, simplify the operation process, but also can ensure that the effluent stable nitrogen standard.

[0077] Specifically, 1) compared with the traditional denitrification process performed by the denitrification sludge, the PDNRA-Anammox process performed by the anaerobic ammonia oxidation sludge can save 60% of the carbon source; 2) compared with the short-range denitrification-anaerobic ammonia oxidation (PDA) process performed by the mixed sludge of denitrification and anaerobic ammonia oxidation, the PDNRA-Anammox process performed by the anaerobic ammonia oxidation sludge obviously does not need to consider the competition problem of microbial community, and the structure of the microbial community is more stable, which can not only effectively cope with the performance fluctuation caused by the large fluctuation of sewage quality and quantity, but also make the start-up and operation and maintenance more convenient; 3) the PDNRA-Anammox biological reaction in the anoxic zone also does not need the short-range nitrification reaction in the O section (aerobic zone), which avoids the complex work of washing the nitrite oxidizing bacteria (NOB) and enriching the ammonia oxidizing bacteria (AOB) required by the short-range nitrification-anaerobic ammonia oxidation (PNA) process, and greatly reduces the operation and maintenance difficulty of the O section.

[0078] S1214, the mixed solution with removed nitrogen elements is mixed with iron salt to a target iron-phosphorus ratio for phosphorus removal treatment, and a target effluent is obtained.

[0079] The chemical phosphorus removal unit includes a mixing pool, a flocculation pool and a sedimentation pool connected in sequence, wherein 1) the mixing pool is connected with an iron salt dosing device, and the main function is to ensure that the reagent is rapidly and uniformly distributed in the water, promote the start of the chemical reaction, and the main parameters are: the molar ratio of the dosed iron salt to the total phosphorus in the sewage is 1.5-3.0 (i.e. the target iron-phosphorus ratio), the residence time is 30-60 seconds, and the mixing intensity (G value) is 700-1000 s -1 . 2) The main function of the flocculation pool is that the reagent fully reacts with the phosphate to form larger flocculation bodies, and the main parameters are: the hydraulic retention time is 15-30 minutes, and the stirring intensity (G value) is 20-60 s -1 . 3) The main function of the sedimentation pool is to separate the formed phosphate floc by gravity sedimentation, and the generated sediment is sent to the iron-phosphorus recovery device, and the main parameters are: the surface load is 8-12 m 3 / (m 2 ·h), and the water depth in the sedimentation zone is 3-5 m.

[0080] The setting of the chemical phosphorus removal unit significantly improves the comprehensive performance of the sewage treatment system. By bearing the main phosphorus removal load, the high-speed activated sludge system can be freed from the dependence on maintaining high phosphorus removal efficiency by extending HRT, thereby achieving efficient removal of organic matter and energy recovery under the condition of maintaining short sludge age operation, and truly achieving the design goal of energy saving and efficiency improvement. At the same time, by implementing secondary iron salt precise supplement in the mixing tank, the system not only ensures the full implementation of the iron metabolism process in the anoxic tank, but also avoids the risk of iron pollution caused by excessive addition, and at the same time achieves the deep phosphorus removal goal of the sewage treatment system. The operation data shows that the process configuration effectively coordinates the synergistic operation of the short sludge age activated sludge system and the anaerobic ammonia oxidation denitrification system, so that the denitrification and phosphorus removal efficiency is simultaneously improved.

[0081] In summary, when the effluent ammonia nitrogen concentration value is lower than the preset threshold value, the dual-track municipal sewage treatment system can be controlled to operate in the first mode, the carbon source is optimally configured through the sewage diversion and the setting of the high-speed activated sludge tank, thereby improving the nitrification reaction rate, and providing the carbon source required for the PDNRA reaction for the anaerobic ammonia oxidation bacteria; at the same time, the ferrous iron (Fe 2+ ) accumulated in the anoxic tank during the second mode operation can be used as a complementary reducing agent for organic matter in the sewage, to cooperatively drive the PDNRA reaction to proceed fully, thereby ensuring that the effluent stable nitrogen meets the standard. In this way, while achieving efficient denitrification and phosphorus removal, energy consumption and operation complexity can also be reduced.

[0082] In combination with the first aspect, in step S122, the dual-track municipal sewage treatment system is controlled to operate in the second mode, specifically including:

[0083] S1220, controlling the dual-track working tank in the aerobic unit to operate in the high-speed activated sludge tank mode, and connecting the pipe of the iron salt storage device with the regulating tank and the mixing tank.

[0084] In combination with Figure 3 As shown in the figure, all the sewage enters the high-speed activated sludge tank, and the dual-track working tank operates in the high-speed activated sludge tank mode. This operating mode has double advantages: on the one hand, the organic matter in the sewage is efficiently transferred to the sludge phase through biological adsorption; on the other hand, the sludge activity of the dual-track working tank can be maintained (compared with the operating mode in which the sewage directly bypasses the tank). At the same time, by connecting the pipe of the iron salt storage device with the regulating tank, the system establishes a synergistic mechanism of anaerobic ammonia oxidation bacteria and iron cycle. This operating mode can produce the following benefits: 1) significantly improve the adaptability of the system to low carbon-nitrogen ratio influent, and reduce the demand for additional carbon source; 2) effectively increase the iron reserve in the anoxic tank, and create favorable conditions for subsequent switching to mode one operation.

[0085] In combination with the first aspect, after step S1220, including:

[0086] S1221, the municipal sewage is introduced into two high-speed activated sludge tanks connected in sequence, and for each high-speed activated sludge tank, the dissolved oxygen concentration is controlled to be 0.2-1 mg / L, the sludge retention time is controlled to be 0.1-0.3 d, and the hydraulic retention time is controlled to be 0.125-0.25 h for preliminary purification.

[0087] At this time, the double-track working pool operates in the high-speed activated sludge tank mode, and cooperates with the original high-speed activated sludge tank to jointly realize adsorption and recovery of organic matter.

[0088] S1222, the mud-water mixture after preliminary purification is introduced into a secondary sedimentation tank for separation, and the supernatant is transported to a conditioning tank to be mixed with ferric salt to adjust the mixed liquid to a target iron-nitrogen ratio and a second target pH.

[0089] The supernatant of the secondary sedimentation tank enters the conditioning tank to be mixed with ferric salt, and the iron-nitrogen ratio (Fe 3+ :NH4 + -N = 3:1-5:1), and the pH is controlled to be 7.29-7.32; at the same time, the bottom mud is backflowed to the high-speed activated sludge tank to maintain the sludge concentration (1500-3000 mg / L) in the aerobic zone.

[0090] S1223, the mixed liquid with the target iron-nitrogen ratio and the second target pH is introduced into an anoxic tank for ferric-type anaerobic ammonia oxidation reaction to obtain a mixed liquid with removed nitrogen elements.

[0091] The anoxic tank is filled with anaerobic ammonia oxidation biofilm filler or granular sludge, and mainly occurs ferric-type anaerobic ammonia oxidation (Fe 3+ -Anammox) reaction, which can be expressed as:

[0092] NH4 + + Fe 3+ → N2 + Fe 2+ .

[0093] The process has the following advantages: 1) ammonia nitrogen is efficiently removed without the need for external carbon source and aeration; 2) the iron storage amount of the anoxic tank is significantly improved through the iron metabolism process, providing necessary process conditions for the system to switch back to mode one; 3) iron storage can promote anaerobic ammonia oxidation metabolism.

[0094] S1224, the mixed liquid with removed nitrogen elements is mixed with ferric salt to a target iron-phosphorus ratio and then treated for phosphorus removal to obtain a target effluent.

[0095] The unit realizes triple optimization effects by implementing secondary iron salt precise dosing in the mixing pool: first, ensuring that the iron metabolism process in the anoxic tank is fully carried out, second, avoiding the risk of iron pollution caused by excessive dosing, and finally achieving the goal of deep phosphorus removal in the system. This process configuration effectively coordinates the synergistic effect of nitrogen metabolism and iron metabolism in the anaerobic ammonia oxidation process, significantly improving the simultaneous nitrogen and phosphorus removal efficiency of the system.

[0096] In summary, when the ammonia nitrogen concentration of the effluent of the wastewater treatment system is greater than or equal to the preset threshold, the second operating mode of the dual-track system is switched to. This mode can treat low carbon-nitrogen ratio wastewater without relying on external carbon source, and significantly improve the iron reserves in the anoxic tank through iron metabolism. These iron reserves not only provide the necessary conditions for the subsequent switching back to the first mode, but also continuously promote the anaerobic ammonia oxidation reaction in the first mode, achieving efficient and stable denitrification treatment effect.

[0097] In addition, the present application also connects the pipeline between the dual-track municipal wastewater treatment system and the sludge digestion system.

[0098] The high organic load, low HRT and SRT operating characteristics of the high-speed activated sludge tank determine that the sludge has high biomass yield, high biodegradability and easy digestion characteristics, and the sludge reduction and energy recovery can be maximized through the sludge digestion system.

[0099] Specifically, the step of connecting the pipeline between the dual-track municipal wastewater treatment system and the sludge digestion system includes:

[0100] Sludge pretreatment: The sludge pretreatment unit is connected to the high-speed activated sludge tank, and the sludge in the high-speed activated sludge tank entering the sludge pretreatment unit is subjected to sludge concentration treatment to obtain concentrated sludge with a moisture content of 90%-98% and then enters the sludge digestion unit; at the same time, the concentrated liquid generated is returned to the high-speed activated sludge tank.

[0101] Sludge digestion treatment: The concentrated sludge is subjected to sludge digestion to produce methane in the sludge digestion unit, with a hydraulic retention time of 10-30 days, a temperature control of 35-55℃, a pH control of 6.8-7.5, a volatile fatty acid (VFA) / alkalinity ratio control of less than or equal to 0.3, and an ammonia nitrogen concentration of less than or equal to 3000 mg / L.

[0102] Energy conversion and utilization: The digestion gas generated by the sludge digestion unit can be further transported to a biogas power generation system, treated by an activated carbon purification device to obtain methane gas with a content of 60%-70%; the methane gas is transported to a gas engine, burned to drive the generator set to generate electricity and recover waste heat, and then the electricity and heat energy are converted to obtain electric energy and heat energy; the electric energy and heat energy are transmitted to the municipal wastewater treatment system.

[0103] Disposal of excess digested sludge: The excess digested sludge is sent to a sludge dewatering unit. After dewatering, sludge with a moisture content of 30% to 80% is obtained and used for agricultural applications, incineration, or landfill. The sludge dewatering liquid is returned to the high-speed activated sludge tank.

[0104] Based on the above method, the residual sludge (i.e., sludge from the high-speed activated sludge tank) of the dual-track urban sewage treatment system is disposed of and energy is reused, thereby reducing the cost of sludge disposal and providing energy for the urban sewage treatment system of the present invention.

[0105] Secondly, embodiments of the present invention also provide a dual-track urban wastewater treatment device, applied to the control unit of a dual-track urban wastewater treatment system; the dual-track urban wastewater treatment system further includes an aerobic unit, a secondary sedimentation tank, an equalization tank, an anoxic tank, and a chemical phosphorus removal unit connected in sequence, the input end of the aerobic unit being connected to the wastewater source; the control unit is connected to the dual-track working tank in the aerobic unit, and by adjusting the operating parameters of the dual-track working tank in the aerobic unit, the dual-track working tank is made to operate in either a high-speed activated sludge tank mode or a nitrification tank mode, thereby adjusting the operating mode of the dual-track urban wastewater treatment system; combined with Figure 4 As shown, the device includes: an acquisition module 10 and a control module 20.

[0106] The acquisition module 10 is used to acquire the ammonia nitrogen concentration value of the effluent.

[0107] The control module 20 is used to control the dual-track urban sewage treatment system to operate in the target mode based on the comparison between the ammonia nitrogen concentration value and the preset threshold.

[0108] Thirdly, embodiments of this application provide an electronic device, combined with Figure 5 As shown, the electronic device includes a memory 131 and a processor 130. The memory 131 is used to store computer programs, and the processor 130 is used to run the computer programs to enable the electronic device to perform the methods described above.

[0109] Furthermore, combined Figure 5 The electronic device shown also includes a bus 132 and a communication interface 133, with the processor 130, the communication interface 133 and the memory 131 connected via the bus 132.

[0110] The memory 131 can include a high-speed random access memory (RAM) and can also include a non-volatile memory such as at least one disk memory. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 133 (which can be wired or wireless), and the Internet, a wide area network, a local area network, a metropolitan area network, etc. can be used. The bus 132 can be an ISA bus, a PCI bus, or an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one bidirectional arrow is used to represent the system in the figure, but it does not mean that there is only one bus or one type of bus.

[0111] The processor 130 can be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above method can be completed by the integrated logic circuit of hardware in the processor 130 or the instruction in the form of software. The processor 130 described above can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component. Each method, step and logic block disclosed in the embodiment of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in combination with the embodiment of the present application can be directly embodied as a hardware code processor for execution, or a combination of hardware and software modules in the code processor for execution. The software module can be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, etc. The storage medium in the art. The storage medium is located in the memory 131, and the processor 130 reads the information in the memory 131 and combines the hardware to complete the steps of the method of the above embodiment.

[0112] In a fourth aspect, the embodiments of the present application provide a storage medium, and the storage medium stores computer program instructions. When the computer program instructions are read and run by a processor, the above method is executed.

[0113] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the foregoing method embodiment, and will not be repeated here.

[0114] In addition, in the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be electrically connected; can be directly connected, can be indirectly connected through an intermediate medium, and can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0115] The functions, if realized in the form of software function units and sold or used as independent products, can be stored in a computer storage medium. Based on such understanding, the technical solutions of the present application or the part of the present application that essentially contributes to the prior art or the part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various program code storage media.

[0116] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0117] Finally, it should be noted that the above examples are merely specific embodiments of the present application, and are used to illustrate the technical solutions of the present application, but are not intended to limit the present application. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that any person skilled in the art can still modify or easily think of changes to the technical solutions recorded in the foregoing examples, or make equivalent replacements to some of the technical features, within the technical range disclosed by the present application. These modifications, changes or replacements do not cause the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A double-track urban sewage treatment method, characterized by, The application relates to a control unit applied to a double-track urban sewage treatment system; the double-track urban sewage treatment system further comprises an aerobic unit, a secondary sedimentation tank, a regulating tank, an anoxic tank and a chemical phosphorus removal unit which are sequentially connected, and an input end of the aerobic unit is connected with a sewage source; the control unit is connected with a double-track working tank in the aerobic unit, working parameters of the double-track working tank in the aerobic unit are adjusted, the double-track working tank is operated in a high-speed activated sludge tank mode or a nitrification tank mode, and the working mode of the double-track urban sewage treatment system is adjusted; the method comprises the following steps: an ammonia nitrogen concentration value of effluent is acquired; if the ammonia nitrogen concentration value is less than a preset threshold value, the double-track urban sewage treatment system is controlled to operate in a first mode; if the ammonia nitrogen concentration value is greater than or equal to the preset threshold value, the double-track urban sewage treatment system is controlled to operate in a second mode, and is switched to the first mode after a preset time length; wherein the step of operating in the first mode comprises the following steps: the double-track working tank in the aerobic unit is controlled to operate in the nitrification tank mode, a pipeline connection between the sewage source and the regulating tank is turned on, and a pipeline connection between an iron salt storage device and a mixing tank in the chemical phosphorus removal unit is turned on; the step of operating in the second mode comprises the following steps: the double-track working tank in the aerobic unit is controlled to operate in the high-speed activated sludge tank mode, and the pipeline connection between the iron salt storage device and the regulating tank and the mixing tank is turned on.

2. The method of claim 1, wherein, After the step of controlling the double-track working tank in the aerobic unit to operate in the nitrification tank mode and turning on the pipeline connection between the sewage source and the regulating tank and the pipeline connection between the iron salt storage device and the mixing tank in the chemical phosphorus removal unit, the following steps are further included: the urban sewage is introduced into a high-speed activated sludge tank with a dissolved oxygen concentration of 0.2-1 mg / L, and is preliminarily purified by controlling a sludge retention time to be 0.2-0.6 d and a hydraulic retention time to be 0.25-0.5 h, and then is introduced into a nitrification tank for nitrification treatment; the sludge-water mixture after the nitrification treatment is introduced into a secondary sedimentation tank for separation, the supernatant is transported to the regulating tank to be mixed with the urban sewage, and the mixed liquid is adjusted to a target nitrogen substrate ratio and a first target pH; the mixed liquid with the target nitrogen substrate ratio and the first target pH is introduced into an anoxic tank for a short-range nitrate dissimilatory reduction to ammonium coupled anaerobic ammonia oxidation reaction, so as to obtain a nitrogen-removed mixed liquid; the nitrogen-removed mixed liquid is mixed with iron salt to a target iron-phosphorus ratio, and then is subjected to phosphorus removal treatment, so as to obtain a target effluent.

3. The method of claim 1, wherein, After the step of controlling the double-track working tank in the aerobic unit to operate in the high-speed activated sludge tank mode and turning on the pipeline connection between the iron salt storage device and the regulating tank and the mixing tank, the following steps are included: the urban sewage is introduced into two high-speed activated sludge tanks which are sequentially connected, and for each high-speed activated sludge tank, the dissolved oxygen concentration is controlled to be 0.2-1 mg / L, the sludge retention time is controlled to be 0.1-0.3 d, and the hydraulic retention time is controlled to be 0.125-0.25 h for preliminary purification; The preliminarily purified sludge-water mixture is introduced into a secondary sedimentation tank for separation, and the supernatant is transported to a conditioning tank to be mixed with ferric salt to adjust the mixture to a target iron-nitrogen ratio and a second target pH; The mixture with the target iron-nitrogen ratio and the second target pH is introduced into an anoxic tank for a ferric-type anaerobic ammonia oxidation reaction to obtain a nitrogen-removed mixture; The nitrogen-removed mixture is mixed with ferric salt to a target iron-phosphorus ratio for phosphorus removal treatment to obtain a target effluent.

4. The method of claim 1, wherein, According to the comparison relationship between the ammonia nitrogen concentration value and the preset threshold value, the step of controlling the double-track urban sewage treatment system to operate in a target mode further includes: turning on the pipeline connection between the double-track urban sewage treatment system and the sludge digestion system.

5. A dual track urban sewage treatment device, characterized in that, A control unit applied to a double-track urban sewage treatment system; the double-track urban sewage treatment system further includes an aerobic unit, a secondary sedimentation tank, a conditioning tank, an anoxic tank, and a chemical phosphorus removal unit connected in sequence, and an input end of the aerobic unit is connected with a sewage source; the control unit is connected with a double-track working tank in the aerobic unit, and by adjusting the working parameters of the double-track working tank in the aerobic unit, the double-track working tank is operated in a high-speed activated sludge tank mode or a nitrification tank mode to adjust the working mode of the double-track urban sewage treatment system; The device is used to execute the method of any one of claims 1-4; the device includes: An acquisition module is configured to acquire an ammonia nitrogen concentration value of an effluent; A control module is configured to control the double-track urban sewage treatment system to operate in a target mode according to a comparison relationship between the ammonia nitrogen concentration value and a preset threshold value.

6. An electronic device, comprising: The electronic device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to run the computer program to make the electronic device execute the method in any one of claims 1 to 4.

7. A storage medium, characterized by The storage medium stores computer program instructions, and the computer program instructions are read and run by the processor to execute the method in any one of claims 1 to 4.

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