Method and system for improving sewage treatment energy efficiency of continuous flow SBR pool

Abstract

The invention discloses a method for improving sewage treatment energy efficiency of a continuous flow SBR (sequencing batch reactor) pool. The method comprises the following steps: performing efficient biological denitrification bacterial sludge culture on the SBR pool by adopting an efficient biological denitrification method; and configuring a sequence control program of the SBR pool for sewage treatment, including a water inlet stage, an aeration stage, a stirring stage, a precipitation stage and a drainage stage until the effluent quality parameter reaches a target design value. By culturing the efficient biological denitrification bacterial sludge of the SBR pool and combining with sequential control logic to efficiently treat sewage, synchronous nitrification and denitrification can be realized, the method is suitable for treating high-temperature wastewater, the sewage treatment efficiency of the SBR pool is improved, the biochemical retention time is shortened, the energy medium cost is saved, and the method is suitable for industrial production. The method has the advantages of stable system, high tolerance, easiness in operation, easiness in large-scale popularization and application and the like.

Description

Technical Field

[0001] The invention relates to a method and a system for improving the energy efficiency of sewage treatment in a continuous flow SBR tank, belonging to the field of industrial sewage treatment. Background Art

[0002] Biological denitrification is a common method for treating ammonia nitrogen in water. Compared with physical and chemical denitrification technology, biological denitrification technology has the advantages of no secondary pollution and low treatment cost, so it is widely used in sewage treatment. At present, there are three main mainstream biological denitrification technologies, namely nitrification and denitrification, short-range nitrification and denitrification, and anaerobic ammonia oxidation. However, high-efficiency biological denitrification technology is a biological denitrification technology based on high-efficiency denitrification bacteria, which has enhanced denitrification performance and takes into account the performance of treating multiple pollutants such as COD. High-efficiency denitrification technology is a special composite bacterial community that is domesticated in a high-ammonia nitrogen base solution. It has the characteristics of traditional nitrification and denitrification bacteria, short-range nitrification and short-range denitrification, and anaerobic ammonia oxidation bacteria in terms of denitrification performance. Compared with anaerobic ammonia oxidation, it exchanges a small amount of carbon source and aeration requirements for the environmental tolerance and proliferation rate of the high-efficiency denitrification bacterial community. At the same time, the high-efficiency biological denitrification system allows electrons to be transferred to the denitrification enzyme system and oxygen at the same time through the action of multiple enzymes, which can achieve denitrification under aerobic conditions. Therefore, under certain environmental conditions, simultaneous nitrification and denitrification can be achieved. While saving energy costs and carbon source costs, high-efficiency denitrification technology has the advantages of system stability, strong tolerance, easy operation, and easy scale-up and promotion.

[0003] In industrial wastewater treatment systems that use traditional biological denitrification technology, the sludge treatment efficiency is low, the biochemical retention time is long, the SBR system treatment capacity is low, and the energy medium treatment cost is high, which cannot meet the needs of industrial enterprises to reduce energy and increase efficiency. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned conventional technologies, the present invention provides a method and system for improving the energy efficiency of sewage treatment in a continuous flow SBR tank, so as to improve the sewage treatment capacity of industrial enterprises.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] A method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank comprises the following steps:

[0007] The high-efficiency biological denitrification method is used to cultivate the high-efficiency biological denitrification bacteria sludge in the SBR pool;

[0008] The sequential control program of the SBR tank is configured to carry out sewage treatment, including the water inlet stage, aeration stage, mixing stage, sedimentation stage and drainage stage, until the effluent water quality parameters reach the target design values.

[0009] Specifically, the SBR pool is cultured with high-efficiency biological denitrification bacteria sludge by using a high-efficiency biological denitrification method, which includes the following steps:

[0010] Inject sewage of a preset proportion height into the SBR tank;

[0011] Add bacterial sludge to the water inlet section of the SBR pool, and add sewage at the same time. When the water level reaches the preset height, start the water circulation;

[0012] Start aeration and stirring procedures;

[0013] Test various parameters of the mixed liquid in the SBR pool. When the parameters reach the target value, the sludge culture is completed and water is injected to the normal working level.

[0014] Specifically, the various parameters of the mixed liquor in the SBR pool include sludge settling ratio SV30, sludge concentration MLSS, dissolved oxygen DO in the biochemical pool, redox potential ORP, sludge settling ratio SV, sludge index SVI, sludge age SRT, and total suspended solids TSS.

[0015] Specifically, the sequential control program of the SBR tank is configured to treat sewage, including the water inlet stage, the aeration stage, the stirring stage, the sedimentation stage and the drainage stage, including the following steps:

[0016] During the water inlet stage, the water inlet volume and phosphate dosage are controlled according to the preset time;

[0017] During the aeration phase, air is introduced according to the preset time, and water circulation control is started, and then the amount of biochemical liquid alkali added is controlled according to the preset time;

[0018] During the stirring stage, stop air intake, start sludge discharge control at the preset time, and control the methanol dosage at the preset time; repeat the aeration stage and stirring stage N times (N>=0), and then stop after aeration at the preset time;

[0019] During the sedimentation stage, the water circulation control is stopped and the mud discharge control is started at the preset time;

[0020] During the drainage stage, the decanting control is started according to the preset time.

[0021] Specifically, the preset control durations of phosphate dosage, methanol dosage, and biochemical liquid alkali dosage are all optional for manual and automatic input, and the switching authority is set in parallel with the main sequential control steps of the water inlet stage, aeration stage, and stirring stage.

[0022] Specifically, the sequential control program of the SBR pool also includes an alarm program, which outputs the cause of the fault when a fault occurs and resets after the fault is eliminated.

[0023] Specifically, a method for improving the energy efficiency of continuous flow SBR pool sewage treatment also includes the following steps: when the bacterial sludge in the first SBR pool is completed and enters the normal sewage treatment procedure, the bacterial sludge is introduced into the bacterial sludge in the second SBR pool for expansion cultivation, and the expansion cultivation and sequential control procedures are repeated, and this process is repeated to achieve multi-pool expansion cultivation of the target number of SBR pools.

[0024] A system for improving the energy efficiency of sewage treatment in a continuous flow SBR pool comprises: an inlet pump, an inlet valve, a blower, a circulation pump, a decanter, a sludge pump, a biochemical liquid alkali dosing device, a methanol dosing device, and a phosphate dosing device.

[0025] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor is used to call computer instructions in the memory to execute any of the above methods for improving the energy efficiency of continuous flow SBR tank sewage treatment.

[0026] A computer-readable storage medium stores a computer program, wherein when the computer instructions are executed, the device where the storage medium is located is controlled to execute any of the above methods for improving the energy efficiency of continuous flow SBR tank sewage treatment.

[0027] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0028] The efficient biological denitrification system adopted by the present invention has enhanced denitrification performance, and can take into account the performance of treating multiple pollutants such as COD; the rich bacterial community has stronger adaptability and impact resistance to the biochemical system; it can also realize nitrate-oxygen co-metabolism, increase the conditions of denitrification reaction, and then enhance the denitrification effect, improve the treatment capacity, and realize simultaneous nitrification and denitrification; it is also suitable for operation under high temperature conditions (35-40°C), and is suitable for treating high-temperature wastewater in the gasification section without affecting the treatment capacity. The present invention improves the sewage treatment efficiency of the SBR pool, shortens the biochemical residence time, saves energy medium costs, and has the advantages of stable system, strong tolerance, easy operation, and easy to expand the scale of promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0030] Figure 1 A schematic flow chart of a method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank provided in an embodiment of the present invention.

[0031] Figure 2 A sewage treatment control flow chart of a method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank provided in an embodiment of the present invention.

[0032] Figure 3 A host computer HMI diagram of a system for improving the energy efficiency of continuous flow SBR tank sewage treatment provided in an embodiment of the present invention.

[0033] Figure 4 A sequential control logic diagram of a system for improving the energy efficiency of sewage treatment in a continuous flow SBR tank provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0035] Embodiment 1

[0036] See also Figure 1 , Figure 1 A schematic flow chart of a method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank provided in an embodiment of the present invention. In an embodiment of the present application, the method comprises:

[0037] S110, using high-efficiency biological denitrification method to cultivate high-efficiency biological denitrification bacteria sludge in SBR pool. High-efficiency biological denitrification technology is a special composite bacterial community, which is domesticated in a high-ammonia nitrogen base liquid. In terms of denitrification performance, it has the characteristics of traditional nitrification and denitrification bacteria, short-range nitrification and short-range denitrification and anaerobic ammonia oxidation bacteria; compared with anaerobic ammonia oxidation, it exchanges a small amount of carbon source and aeration requirements for the high-efficiency denitrification bacteria community's tolerance to the environment and the increase in proliferation rate; at the same time, the high-efficiency biological denitrification system allows electrons to be transferred to the denitrification enzyme system and oxygen at the same time through the action of multiple enzymes, which can realize denitrification under aerobic conditions. Therefore, under certain environmental conditions, simultaneous nitrification and denitrification can be achieved.

[0038] S120, configure the sequential control program of the SBR tank to treat sewage, including the water inlet stage, aeration stage, mixing stage, sedimentation stage and drainage stage, until the effluent water quality parameters reach the target design value. Figure 2 .

[0039] like Figure 2 As shown, Figure 2 A sewage treatment control flow chart of a method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank provided in an embodiment of the present invention.

[0040] S210, water inlet stage, controlling water inlet and phosphate dosage according to preset time; the preset time interval of water inlet is 0-999 minutes, and the preset time interval of phosphate dosage is 0-99 minutes;

[0041] S220, aeration stage, air is introduced according to the preset time, and water flow circulation control is started, and then the dosage of biochemical liquid alkali is controlled according to the preset time; the aeration method adopts two methods: intermittent aeration and continuous aeration; the aeration gas source uses pure oxygen or air; the preset time interval of the dosage of biochemical liquid alkali is 0-99 minutes;

[0042] S230, in the stirring stage, the air intake is stopped, the sludge discharge control is started according to the preset time, and the methanol dosage is controlled according to the preset time; the preset time interval of the methanol dosage is 0-999 minutes;

[0043] Repeat the aeration stage and stirring stage N times (N>=0), and then stop aeration after the preset time. The aeration gas source is air or pure oxygen;

[0044] S240, sedimentation stage, stop water circulation control, start mud discharge control according to the preset time; the preset time interval of mud discharge is 0-999 minutes;

[0045] S250, drainage stage, decanting control is started according to the preset time; the preset time interval of decanting is 0-99 minutes.

[0046] Embodiment 2

[0047] A system for improving the energy efficiency of sewage treatment in a continuous flow SBR tank is used to implement the above-mentioned method for improving the energy efficiency of sewage treatment in a continuous flow SBR tank. The system includes: an inlet pump, an inlet valve, a blower, a circulation pump, a decanter, a sludge pump, a biochemical liquid alkali dosing device, a methanol dosing device, and a phosphate dosing device.

[0048] Embodiment 3

[0049] Take the sewage treatment project of a chemical enterprise as an example. Before the high-efficiency biological denitrification method was used to improve the energy efficiency of sewage treatment in the SBR pool, the water treatment capacity of a single SBR pool was less than 30m3 / h, the biochemical retention time was long, the treatment capacity was low, and the energy medium cost was high.

[0050] At the beginning of strain debugging, 17 tons of bacterial sludge was put in, the moisture content was 95%, the SBR pool concentration was 3000-6000 mg / L, the SVI was 85-120, and SV30 ≥ 30%.

[0051] First, fill the SBR pool and biochemical pool with 1 / 4 of sewage, then add the inoculated sludge to the water inlet section of the SBR pool, and at the same time, add sewage. After the water level exceeds 1 / 2 and submerges the aerator for more than 1 meter, start the aeration system to ensure the circulation of water below the liquid level. In the early stage of sludge cultivation, since the sludge has not yet been formed in large quantities, the flocculation performance of the generated sludge is not very good and it is still in a discrete state. In addition, the sludge concentration is low and the microorganisms are prone to endogenous respiration. Therefore, the aeration volume of the blower should not be too large, and it is better to stir and mix. During the sludge cultivation process, not only should the SV30 (sludge settling ratio) and MLSS (sludge concentration) of the mixed liquid in the aeration tank be measured in the morning and evening, but also the biological phase of the sludge should be observed at any time. While observing the apparent color of the sludge, the growth of the bacterial flocs and indicator microorganisms should be understood through microscopic examination, so as to make necessary adjustments to the cultivation process according to the situation. When the SV30 value is stably higher than 20%, the SVI (sludge index) is lower than 120mL / g, and the sludge concentration is higher than 1500mg / L, start to fill the tank with water to the normal working level, and control the amount of residual sludge discharged by observing the SV30 value. The initial sludge discharge should not be too large. Measure the dissolved oxygen value, COD (chemical oxygen demand), ammonia nitrogen value, etc. at different time periods. At this time, the cultured and domesticated activated sludge should have a compact structure, clear edges, large sludge flocs, and good adsorption and sedimentation properties. The flocs are based on bacterial flocs, with a small amount of filamentous bacteria interspersed, and the micro-animals are mainly fixed fiber worms, such as bell worms, cover ciliates, and branch worms, and occasionally a small amount of swimming ciliates can be seen.

[0052] When the following conditions are met, the intermittent water discharge of the SBR system can be carried out:

[0053] (1) The sludge concentration is greater than 2 g / L, and the sedimentation is good, and the SV30 is stable greater than 15%;

[0054] (2) After sludge sedimentation, the supernatant is clear and the COD value is less than 70 mg / L.

[0055] (3) Microscopic examination of activated sludge revealed a rich variety of microorganisms, with coarse and dense flocs containing a large number of protozoa and metazoa.

[0056] (4) The dissolved oxygen in the SBR tank shall not be less than 2.5 mg / L.

[0057] (5) When the SBR pool treats 80% of the designed water volume and the sludge concentration and activity meet the design requirements, process water quality debugging is carried out.

[0058] The effluent water quality meets the design requirements as shown in Table 1 below. The indicators such as sludge discharge volume and sludge age all reach the design values, and the commissioning is completed.

[0059] Table 1:

[0060]

[0061] The sequential control procedure of the SBR pool includes the following steps:

[0062] S310, start and confirm whether various equipment (circulation pump, blower, decanter, sludge pump, biochemical alkali dosing pump, methanol dosing pump, phosphate dosing pump), various instruments (DO, PH, ORP, liquid level, temperature, COD, ammonia nitrogen, nitric nitrogen) and operation procedures of the SBR pool system can work normally. If yes, proceed to the next step; otherwise, an alarm prompts;

[0063] S320, open the water inlet valve for a preset time (e.g., 30 seconds); start the water inlet pump for a preset time (e.g., 72 minutes), and start the phosphate dosing pump for a preset time (e.g., 10 minutes), and set the "on / off authority" for the phosphate dosing pump operation; when the phosphate dosing pump fails, it does not affect the operation of the water inlet sequence; after the above steps are completed, turn off the water inlet pump and the water inlet valve;

[0064] S330, start the blower for a preset time (e.g., 90 minutes), start the circulation pump at the same time, start the biochemical alkali dosing pump after the blower operation timing ends, for a preset time (e.g., 30 minutes), and then start the blower again after the biochemical alkali dosing pump operation timing ends, for a preset time (e.g., 120 minutes); the blower frequency is variable during operation; after the above steps are completed, turn off the biochemical alkali dosing pump and the blower;

[0065] S340, start the sludge pump for a preset time (e.g., 60 minutes), and after the sludge pump operation timing ends, start the methanol dosing pump for a preset time (e.g., 30 minutes). After the above steps are completed, turn off the methanol dosing pump;

[0066] Repeat the above steps S330 and S340, but it should be noted that when repeating step S340, the mud pump is not started; in the debugging process of this embodiment, after repeating the above steps 5 times, the blower is started for a preset time (for example, 30 minutes), and the aeration gas source is air, and the oxygenation reaction is carried out. The blower is turned off after the timing ends.

[0067] S350, stop the circulation pump for a preset time (e.g., 60 minutes), start the mud discharge pump for a preset time (e.g., 30 minutes), and stop the mud discharge pump after the running timer ends;

[0068] S360, start the decanter, the decanter descends at a preset frequency (for example, 30 Hz), and when it descends to the right position, the decanter is left to stand for a preset time (for example, 50 minutes), and then it starts to rise after the timing ends.

[0069] In this embodiment, the sewage is efficiently treated through the sludge culture debugging combined with the sequential control logic, so that the water treatment capacity of a single SBR pool reaches 90m3 / h, and the effluent water quality meets the requirements of COD≤38mg / L, ammonia nitrogen≤2mg / L, and total nitrogen≤10mg / L, and the biochemical reaction residence time is not higher than 73 hours (excluding sedimentation and drainage time).

[0070] In this embodiment, the second and third SBR pools are also included in the high-efficiency biological denitrification sludge expansion culture. When the sludge culture in the first SBR pool is completed and enters the normal sewage treatment procedure, the sludge is introduced into the second SBR pool for expansion culture, and the expansion culture and sequential control procedures are repeated. After the sludge culture in the second SBR pool is completed and enters the normal sewage treatment procedure, the sludge is introduced into the third SBR pool for expansion culture, and the expansion culture and sequential control procedures are repeated to achieve multi-pool expansion culture.

[0071] See also Figure 3 , Figure 4 The host computer interface of this embodiment is beautiful, well-planned and easy to operate. Clear program steps, visible status of each device, eye-catching alarm display, with manual, automatic, start, stop, emergency stop, fault reset, switching and other functions. By collecting the control points of the pump, valve, instrument (PH, ORP, NH3-N, COD, nitrate nitrogen, temperature, flow, liquid level, etc.) of the target SBR pool, intelligent remote monitoring is carried out, and control logic is improved according to the program logic control determined by debugging.

[0072] Furthermore, this embodiment also provides an electronic device, which includes a processor and a memory, wherein the memory stores computer instructions that can be executed on the processor, and the processor is used to call the computer instructions in the memory to execute the method for improving the energy efficiency of continuous flow SBR tank sewage treatment as mentioned above.

[0073] In addition, this embodiment also provides a storage medium, which is used to store computer instructions, wherein when the computer instructions are executed, the device where the storage medium is located is controlled to execute the method for improving the energy efficiency of continuous flow SBR tank sewage treatment as described above.

[0074] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment, characterized in that: The following steps are involved: The high-efficiency biological denitrification method is used to cultivate the high-efficiency biological denitrification bacteria sludge in the SBR pool; The sequential control program of the SBR tank is configured to carry out sewage treatment, including the water inlet stage, aeration stage, mixing stage, sedimentation stage and drainage stage, until the effluent water quality parameters reach the target design values.

2. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 1, characterized in that: The method of using the efficient biological denitrification method to culture the SBR pool with efficient biological denitrification bacteria sludge comprises the following steps: Inject sewage of a preset proportion height into the SBR tank; Add bacterial sludge to the inlet section of the SBR pool, and add sewage at the same time. When the water level reaches the preset height, start the water circulation; Start aeration and stirring procedures; Test various parameters of the mixed liquid in the SBR pool. When the parameters reach the target value, the sludge culture is completed and water is injected to the normal working level.

3. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 2, characterized in that: The various parameters of the mixed liquor in the SBR pool include sludge settling ratio SV30, sludge concentration MLSS, dissolved oxygen DO in the biochemical pool, oxidation-reduction potential ORP, sludge settling ratio SV, sludge index SVI, sludge age SRT, and total suspended solids TSS.

4. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 1, characterized in that: The sequential control procedure of configuring the SBR tank for sewage treatment includes a water intake stage, an aeration stage, a stirring stage, a sedimentation stage and a drainage stage, and includes the following steps: During the water inlet stage, the water inlet volume and phosphate dosage are controlled according to the preset time; During the aeration phase, air is introduced according to the preset time, and water circulation control is started, and then the amount of biochemical liquid alkali added is controlled according to the preset time; During the stirring stage, stop air intake, start sludge discharge control at the preset time, and control the methanol dosage at the preset time; repeat the aeration stage and stirring stage N times (N>=0), and then stop after aeration at the preset time; During the sedimentation stage, the water circulation control is stopped and the mud discharge control is started at the preset time; During the drainage stage, the decanting control is started according to the preset time.

5. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 4, characterized in that: The preset control durations of the phosphate dosage, methanol dosage, and biochemical liquid alkali dosage are all optional for manual and automatic input, and the switching authority is set in parallel with the main sequential control steps of the water inlet stage, aeration stage, and stirring stage.

6. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 4, characterized in that: The sequential control program of the SBR tank also includes an alarm program. When a fault occurs, the cause of the fault is output and reset after the fault is eliminated.

7. A method for improving the energy efficiency of continuous flow SBR tank sewage treatment according to claim 1, characterized in that: The following steps are also included: When the bacterial sludge in the first SBR pool is completed and enters the normal sewage treatment procedure, the bacterial sludge is introduced into the second SBR pool for expansion cultivation, and the expansion cultivation and sequential control procedures are repeated, and this process is repeated to achieve multi-pool expansion cultivation of the target number of SBR pools.

8. A system for improving the energy efficiency of continuous flow SBR tank sewage treatment, used for implementing the method described in any one of claims 1 to 7, characterized in that: The system comprises: a water inlet pump, a water inlet valve, a blower, a circulation pump, a decanter, a mud discharge pump, a biochemical liquid alkali dosing device, a methanol dosing device, and a phosphate dosing device.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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