An automatic adjustment system for the nitrification liquor return flow rate of pig farm wastewater

Abstract

This invention provides an automatic adjustment system for the reflux flow rate of nitrified liquid from pig farm wastewater, comprising an anaerobic reactor, a primary anoxic tank, a primary aerobic tank, a secondary anoxic tank, a secondary aerobic tank, and a biochemical sedimentation tank connected in sequence; a first reflux pump is installed between the primary aerobic tank and the primary anoxic tank, and a second reflux pump is installed between the secondary aerobic tank and the secondary anoxic tank. The system also includes a control system, comprising a control assembly, a first online total nitrogen detector, a first water flow meter, a first frequency converter, a second online total nitrogen detector, a second water flow meter, and a second frequency converter. The first online total nitrogen detector and the first water flow meter are sequentially installed between the anaerobic reactor and the primary anoxic tank; the second online total nitrogen detector and the second water flow meter are sequentially installed between the primary aerobic tank and the secondary anoxic tank. This invention achieves automatic adjustment of the nitrified liquid reflux flow rate by calculating and sending feedback signals to the reflux pumps through the control assembly.

Description

Technical Field

[0001] This utility model relates to the field of water treatment equipment, specifically to an automatic adjustment system for the return flow of nitrification liquid from pig farm wastewater. Background Technology

[0002] Existing biological treatment systems for pig farm wastewater mostly employ an anaerobic + two-stage AO + sedimentation tank process. Due to the high concentrations of ammonia nitrogen and total nitrogen in pig farm wastewater (800-1200 mg / L), a two-stage AO nitrification liquor recirculation process is required for denitrification. A nitrification liquor recirculation pump is installed at the aerobic tank end to recirculate the mixed liquor from the aerobic tank to the anoxic tank, thereby achieving the purpose of denitrification. Due to the high concentrations of ammonia nitrogen and total nitrogen, in order to meet the requirements of treated effluent, the nitrification liquor recirculation flow rate is usually designed to be four times the influent flow rate, thus requiring high pump power.

[0003] However, the daily treatment volume of pig farm wastewater and the total nitrogen concentration in the influent vary greatly throughout the year. When the wastewater volume is very low at certain times of the year, the fixed nitrification liquid return flow not only exceeds the actual needs, resulting in excessively high dissolved oxygen concentration in the anoxic tank, but also wastes energy. Utility Model Content

[0004] The purpose of this invention is to address the problems existing in the prior art by providing an automatic adjustment system for the nitrification liquid return flow rate of pig farm wastewater. The system achieves automatic adjustment of the nitrification liquid return flow rate by calculating the control assembly and using feedback signals to control the return pump.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An automatic adjustment system for the reflux flow rate of nitrified liquor from pig farm wastewater includes an anaerobic reactor, a primary anoxic tank, a primary aerobic tank, a secondary anoxic tank, a secondary aerobic tank, and a biochemical sedimentation tank connected in sequence; a first reflux pump is also provided between the primary aerobic tank and the primary anoxic tank to reflux the mixed liquor from the primary aerobic tank back to the primary anoxic tank; a second reflux pump is also provided between the secondary aerobic tank and the secondary anoxic tank to reflux the mixed liquor from the secondary aerobic tank back to the secondary anoxic tank; and a control system is also included.

[0007] The control system includes a control assembly, a first online total nitrogen detection device, a first water flow meter, a first frequency converter, a second online total nitrogen detection device, a second water flow meter, and a second frequency converter.

[0008] The data input terminals of the control assembly are respectively connected to the first online total nitrogen detection device, the first water flow meter, the second online total nitrogen detection device, and the second water flow meter; the data output terminals of the control assembly are respectively connected to the first return pump through the first frequency converter and to the second return pump through the second frequency converter.

[0009] A first total nitrogen online detection device and a first water flow meter are sequentially installed between the anaerobic generator and the primary anoxic tank; a second total nitrogen online detection device and a second water flow meter are sequentially installed between the primary aerobic tank and the secondary anoxic tank.

[0010] Furthermore, a first reflux flow meter and a second reflux flow meter are also provided; the first reflux flow meter and the second reflux flow meter are respectively connected to the data input terminal of the control assembly;

[0011] A first reflux flow meter is installed between the primary anoxic tank and the first reflux pump; a second reflux flow meter is installed between the secondary anoxic tank and the second reflux pump.

[0012] Furthermore, the first water flow meter, the second water flow meter, the first reflux flow meter, and the second reflux flow meter are electromagnetic flow meters.

[0013] This invention relates to an automatic adjustment system for the nitrification liquor return flow rate of pig farm wastewater. It uses an online total nitrogen detection device and a flow meter to detect the total nitrogen concentration and influent flow rate, and adjusts the power of the return pump in real time based on the actual values, thereby achieving automated adjustment of the nitrification liquor return flow rate. The system enables more intelligent and stable wastewater treatment, while also saving energy. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of an automatic adjustment system for the nitrification liquid return flow of pig farm wastewater provided by this utility model. Detailed Implementation

[0015] The technical solution of this utility model will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0016] Example 1

[0017] like Figure 1 As shown, the present invention provides an automatic adjustment system for the reflux flow of nitrified liquid from pig farm wastewater, comprising an anaerobic reactor 1, a primary anoxic tank 2, a primary aerobic tank 3, a secondary anoxic tank 4, a secondary aerobic tank 5, and a domestic sedimentation tank 6 connected in sequence; a first reflux pump 31 is also provided between the primary aerobic tank 3 and the primary anoxic tank 2 to reflux the mixed liquid from the primary aerobic tank 3 back to the primary anoxic tank 2; a second reflux pump 51 is also provided between the secondary aerobic tank 5 and the secondary anoxic tank 4 to reflux the mixed liquid from the secondary aerobic tank 5 back to the secondary anoxic tank 4; and a control system 7 is also included.

[0018] The control system 7 includes a control assembly 71, a first online total nitrogen detection device 72, a first water flow meter 73, a first frequency converter 74, a second online total nitrogen detection device 75, a second water flow meter 76, and a second frequency converter 77.

[0019] The data input terminals of the control assembly 71 are respectively connected to the first online total nitrogen detection device 72, the first water flow meter 73, the second online total nitrogen detection device 75, and the second water flow meter 76; the data output terminals of the control assembly 71 are respectively connected to the first return pump 31 through the first frequency converter 74 and to the second return pump 51 through the second frequency converter 77.

[0020] A first total nitrogen online detection device 72 and a first water flow meter 73 are sequentially installed between the anaerobic generator and the first-stage anoxic tank 2; a second total nitrogen online detection device 75 and a second water flow meter 76 are sequentially installed between the first-stage aerobic tank 3 and the second-stage anoxic tank 4.

[0021] Wastewater first enters the anaerobic generator, then passes through various treatment tanks in sequence, and finally undergoes sedimentation treatment in the domestic sedimentation tank 6 before being discharged. This process is exactly the same as existing technology, and the structure of each tank is consistent with existing technology, so it will not be described in detail here.

[0022] The improvement of this utility model is that it is equipped with a control assembly 71 and various detection units. By detecting the total nitrogen concentration and flow rate at the corresponding nodes, the power of the reflux pump is adjusted according to the parameters to make the reflux flow rate of the nitrification liquid match the optimal state.

[0023] The specific process is as follows:

[0024] For the nitrification liquid loop between the primary aerobic tank 3 and the primary anoxic tank 2, the control assembly 71 collects the total nitrogen data and flow data signals of the first total nitrogen online detection device 72 and the first water flow meter 73 at regular intervals (e.g., every 2 hours) to obtain the wastewater parameters entering the primary anoxic tank 2 and the primary aerobic tank 3.

[0025] Because the retention time in the biological treatment tanks of the pig farm wastewater project is relatively long, when the total retention time of the primary anoxic tank 2 and the primary aerobic tank 3 is several days (e.g., 3 days), the average value of the data for the corresponding number of days is obtained as the average value of the flow rate and total nitrogen data. Substituting the flow rate, total nitrogen data, and the target value for total nitrogen treatment into the pre-set calculation logic, the required nitrification liquid return flow rate can be derived. This return flow rate value is collected and calculated at regular intervals (e.g., every 2 hours), thereby achieving automatic control of the return flow rate.

[0026] Subsequently, the control assembly 71 sends an adjustment command to the first frequency converter 74 to adjust the operating frequency of the first return pump 31, thereby controlling the return flow rate of the nitrified liquid between the first aerobic tank 3 and the first anoxic tank 2.

[0027] Similarly, the process of controlling the return flow of nitrified liquid between the secondary aerobic tank 5 and the primary anoxic tank 2 is similar to the above process. It only requires collecting the total nitrogen data and flow data signals from the second online total nitrogen detection device 75 and the second water flow meter 76, and then controlling the second frequency converter 77 after calculation.

[0028] As a further improvement, the control system 7 is also equipped with a first reflux flow meter 78 and a second reflux flow meter 79; the first reflux flow meter 78 and the second reflux flow meter 79 are respectively connected to the data input terminal of the control assembly 71. The first reflux flow meter 78 is installed between the primary anoxic tank 2 and the first reflux pump 31; the second reflux flow meter 79 is installed between the secondary anoxic tank 4 and the second reflux pump 51.

[0029] The instantaneous change in the flow rate of the first return pump 31 is fed back to the control center in real time through the first return flow meter 78. The control center adjusts the first frequency converter 74 to the target value based on the real-time flow data, making the system a closed-loop system and achieving precise control. The application of the second return flow meter 79 is similar.

[0030] Preferably, the first water flow meter 73, the second water flow meter 76, the first reflux flow meter 78, and the second reflux flow meter 79 are electromagnetic flow meters. The measurement accuracy of electromagnetic flow meters is not affected by changes in fluid density, viscosity, temperature, pressure, and conductivity, thus they have high measurement accuracy and play an important role in the precise control of the control system 7.

[0031] This utility model provides an automatic adjustment system for the nitrification liquor return flow rate of pig farm wastewater. It deploys online total nitrogen monitoring devices and flow meters at various stages of wastewater treatment, adjusting the nitrification liquor return flow rate in real time based on actual dynamic data to achieve optimal parameter matching. The entire process is automatic and highly intelligent, while effectively reducing energy consumption.

[0032] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A system for automatic adjustment of the return flow of nitrified liquid from swine wastewater, characterized in that: It includes an anaerobic reactor, a primary anoxic tank, a primary aerobic tank, a secondary anoxic tank, a secondary aerobic tank, and a biochemical sedimentation tank connected in sequence; a first reflux pump is also provided between the primary aerobic tank and the primary anoxic tank to reflux the mixed liquor from the primary aerobic tank back to the primary anoxic tank; a second reflux pump is also provided between the secondary aerobic tank and the secondary anoxic tank to reflux the mixed liquor from the secondary aerobic tank back to the secondary anoxic tank; it also includes a control system; The control system includes a control assembly, a first online total nitrogen detection device, a first water flow meter, a first frequency converter, a second online total nitrogen detection device, a second water flow meter, and a second frequency converter; The data input terminals of the control assembly are respectively connected to the first online total nitrogen detection device, the first water flow meter, the second online total nitrogen detection device, and the second water flow meter; the data output terminals of the control assembly are respectively connected to the first return pump through the first frequency converter and to the second return pump through the second frequency converter. A first total nitrogen online detection device and a first water flow meter are sequentially installed between the anaerobic generator and the primary anoxic tank; a second total nitrogen online detection device and a second water flow meter are sequentially installed between the primary aerobic tank and the secondary anoxic tank.

2. The automatic adjustment system for the effluent quantity of the swine wastewater nitrification liquid according to claim 1, characterized in that: It also includes a first reflux flow meter and a second reflux flow meter; the first reflux flow meter and the second reflux flow meter are respectively connected to the data input terminal of the control assembly; A first reflux flow meter is installed between the primary anoxic tank and the first reflux pump; a second reflux flow meter is installed between the secondary anoxic tank and the second reflux pump.

3. The automatic adjustment system of the effluent quantity of the swine wastewater nitrification liquid according to claim 2, characterized in that: The first water flow meter, the second water flow meter, the first reflux flow meter, and the second reflux flow meter are electromagnetic flow meters.

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