Automatic carbon source feeding system

Abstract

The utility model relates to an automatic carbon source adding system which comprises a water inlet monitoring and pretreatment module, a sewage treatment collection module, a carbon source adding amount control module, a carbon source adding unit, a feed-forward module, a feedback compensation module and a tail end verification module, the water inlet monitoring and pretreatment module is connected with the input end of the sewage treatment collection module; the output ends of the feed-forward module and the feedback compensation module are both in communication connection with the input end of the carbon source dosage control module; the input end of the feed-forward module is in communication connection with the output end of the water inlet monitoring and preprocessing module; the input end of the feedback compensation module is in communication connection with the output end of the sewage treatment collection module and the output end of the tail end verification module; the input end of the tail end verification module is in communication connection with the output end of the sewage treatment collection module; the input end of the carbon source adding unit is in communication connection with the output end of the carbon source adding amount control module, and the output end of the carbon source adding unit is connected with the sewage treatment collection module.

Description

Technical Field

[0001] The utility model relates to an automatic carbon source adding system, belonging to the technical field of sewage treatment. Background Art

[0002] Denitrification nitrogen removal uses organic matter as an electron donor to reduce nitric nitrogen in sewage to nitrogen gas. Therefore, the content of organic substrate has a great influence on the denitrification efficiency. At present, many studies and actual engineering operation experience have shown that the influent carbon-nitrogen ratio of many domestic sewage treatment plants is low and the carbon source is insufficient, resulting in unsatisfactory biological denitrification effect and the need to supplement the carbon source.

[0003] At present, the common carbon source automatic addition method is the carbon source addition control method based on feedforward-feedback, that is, by setting up online measuring instruments for influent water quality related indicators and online measuring instruments for total effluent water quality related indicators, feedforward and feedback are combined to automatically control the carbon source addition amount through the PLC controller. This method is because the sewage generally stays in the treatment system for more than ten hours, and the influent water quality and effluent water quality at the same time are poorly correlated, resulting in a certain lag in feedback. The carbon source addition amount determined by it is not accurate, resulting in large fluctuations in the total nitrogen in the effluent and additional addition of carbon sources to increase operating costs. Further improvement is needed. On this basis, there is also an automatic adjustment of carbon source addition by increasing the monitoring of nitrate nitrogen concentration in the anoxic zone. However, because the main body of total nitrogen in conventional sewage treatment is composed of ammonia nitrogen and nitrate nitrogen, only monitoring the nitrate nitrogen concentration in the anoxic zone cannot accurately predict the total nitrogen concentration in the effluent of the sewage plant. The setting value of nitrate nitrogen in the anoxic zone often needs to assume the ammonia nitrogen value first, and there are also problems such as inaccurate carbon source addition and large fluctuations in effluent water quality. Utility Model Content

[0004] In order to solve the above problems existing in the prior art, the utility model provides a carbon source automatic dosing system.

[0005] The technical solution of the utility model is as follows:

[0006] The utility model proposes an automatic carbon source dosing system, comprising an inlet water monitoring and pretreatment module, a sewage treatment assembly module, a carbon source dosage control module, a carbon source dosing unit, a feedforward module, a feedback compensation module and a terminal verification module; the inlet water monitoring and pretreatment module is connected to the input end of the sewage treatment assembly module; the output ends of the feedforward module and the feedback compensation module are both communicatively connected to the input end of the carbon source dosage control module; the input end of the feedforward module is communicatively connected to the output end of the inlet water monitoring and pretreatment module; the input end of the feedback compensation module is communicatively connected to the output end of the sewage treatment assembly module and the output end of the terminal verification module respectively; the input end of the terminal verification module is communicatively connected to the output end of the sewage treatment assembly module; the input end of the carbon source dosing unit is communicatively connected to the output end of the carbon source dosage control module, and the output end is connected to the sewage treatment assembly module;

[0007] The inlet monitoring and pretreatment module is used to monitor the inlet volume and the concentration of pollutants in the inlet water, and pretreat the pollutants in the sewage based on the subsequent sewage treatment steps; the sewage treatment assembly module is used for sewage treatment and disinfection; the feedforward module is used to predict the dosage of the carbon source according to the inlet volume and the concentration of pollutants in the inlet water; the feedback compensation module is used to adjust the dosage of the carbon source of the feedforward module; the terminal verification module is used to test the pollutant content in the final sewage and adjust the adjustment amount of the feedback compensation module; the carbon source dosage control module is used to control the action of the carbon source addition unit according to the test results of the feedforward module, the feedback compensation module and the terminal verification module; the carbon source addition unit is used to receive the action signal of the carbon source dosage control module and add the carbon source to the sewage treatment assembly module.

[0008] Preferably, the sewage treatment assembly module includes an anaerobic zone, an anoxic zone, an aerobic zone, a secondary sedimentation tank, a deep treatment unit and a disinfection unit, and the anaerobic zone, anoxic zone, aerobic zone, a secondary sedimentation tank, a deep treatment unit and a disinfection unit are connected in sequence; the output end of the anoxic zone is equipped with an online ammonia nitrogen and nitric nitrogen meter, and the output end of the disinfection unit is equipped with an outlet total nitrogen online monitor; the output end of the aerobic zone is connected to the input end of the anoxic zone; the carbon source addition unit is connected to the input end of the anoxic zone; the feedback compensation module is connected to the output end of the anoxic zone; the water inlet pretreatment unit is connected to the input end of the anaerobic zone; the terminal verification module input is communicatively connected to the output end of the disinfection unit.

[0009] Preferably, the water inlet end of the water inlet monitoring and pretreatment module is equipped with a flow meter, a water inlet COD Cr Online monitor and total nitrogen online monitor at the water inlet end.

[0010] Preferably, the carbon source dosing unit includes a dosing pump, a dosing pump frequency converter, a dosing flow meter and a drug storage bin; the dosing flow meter is installed at the output end of the dosing pump; the output end of the dosing pump frequency converter and the drug storage bin are both connected to the input end of the dosing pump, the output end of the dosing pump is installed with a dosing flow meter, and the carbon source dosage control module and the input end of the dosing pump frequency converter are both communicatively connected to the output end of the dosing pump; the input end of the dosing pump frequency converter is communicatively connected to the output end of the carbon source dosage control module.

[0011] The utility model has the following beneficial effects:

[0012] 1. The utility model realizes precise control of the amount of carbon source added through the cooperation of the feedforward module, the feedback compensation module and the terminal verification module, solves the problem of large fluctuations in total nitrogen caused by fluctuations in water volume, water quality and environmental changes, and reduces the waste caused by inaccurate addition of carbon sources.

[0013] 2. The utility model utilizes various online monitoring instruments to carry out real-time monitoring of the water inlet and outlet of each module. By real-time monitoring of the concentrations of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone, the sum of the two is kept within a controllable range, thereby ensuring the stability of the total nitrogen value of the effluent, and thus improving the total nitrogen control value of the effluent of the sewage treatment plant to a higher level.

[0014] 3. The utility model realizes accurate control and monitoring of the dosage of the dosing pump through the dosing pump frequency converter and the dosing pump flow meter, and can also monitor the working status of the dosing pump by real-time monitoring of the flow data. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of the utility model;

[0016] Figure 2 It is a detailed structural diagram of the utility model.

[0017] The reference numerals in the figure are as follows:

[0018] 81. Flow meter; 82. Inlet CODCr online monitor; 83. Inlet total nitrogen online monitor; 84. Ammonia nitrogen and nitrate nitrogen meter; 85. Outlet total nitrogen online monitor; 86. Dosing pump flow meter. DETAILED DESCRIPTION

[0019] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Embodiment 1:

[0021] See also Figure 1, a carbon source automatic dosing system, comprising an inlet water monitoring and pretreatment module, a sewage treatment assembly module, a carbon source dosage control module, a carbon source dosing unit, a feedforward module, a feedback compensation module and a terminal verification module; the inlet water monitoring and pretreatment module is connected to the input end of the sewage treatment assembly module; the output ends of the feedforward module and the feedback compensation module are both communicatively connected to the input end of the carbon source dosage control module; the input end of the feedforward module is communicatively connected to the output end of the inlet water monitoring and pretreatment module; the input end of the feedback compensation module is communicatively connected to the output end of the sewage treatment assembly module and the output end of the terminal verification module respectively; the input end of the terminal verification module is communicatively connected to the output end of the sewage treatment assembly module; the input end of the carbon source dosing unit is communicatively connected to the output end of the carbon source dosage control module, and the output end is connected to the sewage treatment assembly module;

[0022] The inlet monitoring and pretreatment module is used to monitor the inlet volume and the concentration of pollutants in the inlet water, and pretreat the pollutants in the sewage based on the subsequent sewage treatment steps; the sewage treatment assembly module is used for sewage treatment and disinfection; the feedforward module is used to predict the dosage of the carbon source according to the inlet volume and the concentration of pollutants in the inlet water; the feedback compensation module is used to adjust the dosage of the carbon source of the feedforward module; the terminal verification module is used to test the pollutant content in the final sewage and adjust the adjustment amount of the feedback compensation module; the carbon source dosage control module is used to control the action of the carbon source addition unit according to the test results of the feedforward module, the feedback compensation module and the terminal verification module; the carbon source addition unit is used to receive the action signal of the carbon source dosage control module and add the carbon source to the sewage treatment assembly module.

[0023] In this embodiment, the carbon source automatic dosing system is suitable for oxidation ditch, AO, AAO and other processes with biological denitrification function;

[0024] The first step is to determine the feedforward carbon source dosage in the feedforward module, that is, to determine the external carbon source dosage based on the influent water volume and water quality prediction. The specific calculation formula is as follows:

[0025]

[0026] In the formula, q 1 is the external carbon source dosage, in L / h; m is the carbon source dosage coefficient; A i-TN is the total nitrogen concentration in the influent, in mg / L; A O-TN is the total nitrogen concentration in the effluent, in mg / L; Q c is the water inlet flow rate, in m 3 / h; w is the mass concentration of the carbon source agent solution, in mg / L; β is the effective content of the carbon source agent, in %; COD eqCOD equivalent of carbon source agent, unit is mg / mg COD; COD Cr-i Influent COD Cr Concentration, in mg / L.

[0027] It is further stipulated that the value range of m is 4-8, m is pre-set and debugged manually based on operating experience, and the system determines the optimal value through self-learning of the deep learning network based on the debugging results.

[0028] It should also be noted that the frequency of feedforward carbon source dosage adjustment can be adjusted according to the online water quality update cycle of the inlet water; the feedforward carbon source dosage adjustment can be set to trigger adjustment when the deviation of the carbon source dosage calculation result compared with the previous cycle exceeds 15%.

[0029] The second step is to set the total nitrogen threshold of the sewage plant effluent as A according to the discharge standard to be implemented. O-TN (A O-TN Less than the total nitrogen concentration limit of the implementation standard).

[0030] The third step is to determine the total nitrogen threshold of the sewage plant effluent as A O-TN The concentration of ammonia nitrogen in the effluent of the anoxic zone under H , Nitrate nitrogen concentration A O The total concentration threshold A HO ; Among them, the total concentration threshold A HO The calculation of is as follows:

[0031] A HO =A H +A O =A O-TN +A 1

[0032] In the formula, A 1 It is the difference between the total concentration of ammonia nitrogen and nitrate nitrogen in the effluent of the anoxic zone and the total nitrogen concentration in the effluent of the sewage plant when the sewage plant is in stable operation. It has regularity and is relatively stable, generally 0-3 mg / L. 1 It can be set manually based on operating experience, or the control module can determine it through self-learning through statistical analysis of operating process data;

[0033] The fourth step is to determine the feedback compensation: the feedback compensation module is based on the sum of the real-time values ​​of the effluent ammonia nitrogen and nitrate nitrogen concentrations in the anoxic zone monitored by the ammonia nitrogen and nitrate nitrogen instrument and the set effluent ammonia nitrogen and nitrate nitrogen total concentration threshold value A HO The deviation between the two determines the amount of carbon source that needs to be added. The specific steps are as follows:

[0034] 4.1 After obtaining the real-time values ​​of ammonia nitrogen and nitrate nitrogen concentrations in the effluent of the anoxic zone according to the ammonia nitrogen and nitrate nitrogen instrument, send them to the feedback compensation module;

[0035] 4.2 The feedback compensation module determines whether the sum of the real-time values ​​of the effluent ammonia nitrogen and nitric nitrogen concentrations is within the set target value range, and gives an adjustment amount according to the deviation:

[0036] The sum of the real-time concentrations of ammonia nitrogen and nitrate nitrogen in the effluent of the anoxic zone monitored by the ammonia nitrogen and nitrate nitrogen instrument and the total concentration threshold value A of ammonia nitrogen and nitrate nitrogen are recorded. HO The difference is △A HO .

[0037] When -1mg / L≤△A HO When the concentration is ≤1 mg / L, the carbon source is maintained at the current dosage.

[0038] △A HO <-1mg / L, at this time, carbon source supplementation is negative feedback and the amount of carbon source added needs to be reduced.

[0039] △A HO >1mg / L, at this time, carbon source supplementation is positive feedback, and the amount of carbon source added needs to be increased.

[0040] At the same time, in order to exclude feedback compensation caused by instantaneous deviation, the carbon source feedback compensation can be started after the deviation lasts for more than 5-30 minutes.

[0041] The feedback compensation module feeds back the compensation signal to the carbon source dosage control module, and the carbon source dosage control module adjusts the frequency of the dosing pump inverter, thereby adjusting the carbon source dosage. The frequency increase or decrease of the dosing pump inverter each time can be manually set by the central control personnel, or it can be automatically adjusted by the automatic control system according to the deviation between the sum of the real-time values ​​of the effluent ammonia nitrogen and nitric nitrogen concentrations and the set target value after self-learning and summarizing the rules.

[0042] After the dosage of the carbon source feedback compensation described in 4.3 is adjusted, observe the change in the sum of the real-time concentrations of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone to evaluate the effect of this feedback supplement, and then continue with step 4.1;

[0043] In this step, the observation time is the time it takes for the effect of each adjustment of the dosage on the sum of the real-time concentrations of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone to reach stability.

[0044] 4.4 After the carbon source dosage is stabilized, the feedforward module automatically corrects the feedforward carbon source dosage coefficient m based on the deviation between the actual carbon source dosage and the theoretical carbon source dosage.

[0045] The fifth step is to adjust the feedback compensation module through the end verification module. The specific steps are as follows:

[0046] 5.1 The effluent online total nitrogen meter obtains the real-time value of the effluent total nitrogen in the sewage treatment plant and sends it to the terminal calibration module.

[0047] 5.2 The terminal verification module compares the real-time value of total nitrogen with the effluent total nitrogen threshold value AO-TN The deviation situation determines the rationality of the feedback compensation control and performs calibration. The standards are as follows:

[0048] The real-time value of the total nitrogen in the effluent and the threshold value of the total nitrogen in the effluent are recorded as A O-TN The difference is △A O-TN .

[0049] When -0.5mg / L≤△A O-TN When ≤0.5mg / L, the feedback compensation control level is maintained.

[0050] When △A O-TN <-0.5mg / L, at this time, the threshold value A of the total concentration of ammonia nitrogen and nitrate nitrogen for feedback compensation needs to be reduced HO , that is, the A 1 The value should be reduced |△A O-TN |.

[0051] When △A O-TN >0.5mg / L, then the threshold value A of the total concentration of ammonia nitrogen and nitrate nitrogen for feedback compensation needs to be increased HO , that is, the A 1 The value should be increased by △A O-TN .

[0052] In order to eliminate the influence of instantaneous deviation, it can be set to start feedback compensation control level adjustment after the deviation lasts for more than 5-30 minutes.

[0053] 5.3 After the terminal calibration and adjustment of the feedback compensation control level, observe the real-time value of the effluent total nitrogen and the effluent total nitrogen threshold A O-TN Deviation, to evaluate the effect of this terminal calibration adjustment, and then continue with step 5.1, when the real-time value of effluent total nitrogen meets the effluent total nitrogen threshold A O-TN When the system is stable, stop adjusting and keep the system running stably.

[0054] When the system is running, the inlet water quality online instruments (TN, COD Cr ) generally updates the data no less than once an hour. There is a lag in feedforward addition and it is difficult to verify the effect of addition in time. The introduction of feedback supplement can effectively solve this problem; and feedback compensation is mainly to fine-tune the amount of carbon source added to achieve stability of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone. If the inlet water volume and water quality change significantly, the carbon source addition is pre-adjusted through the feedforward module to make up for the problem that the feedback compensation is difficult to achieve in time when the deviation of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone is too large due to abnormal inlet water volume and water quality.

[0055] In this embodiment, the carbon source dosage control module, the feedforward module, the feedback compensation module and the end-point verification module together constitute a control system for carbon source addition, and are controlled by a controller.

[0056] Furthermore, the sewage treatment assembly module includes an anaerobic zone, an anoxic zone, an aerobic zone, a secondary sedimentation tank, a deep treatment unit and a disinfection unit, and the anaerobic zone, anoxic zone, aerobic zone, a secondary sedimentation tank, a deep treatment unit and a disinfection unit are connected in sequence; the output end of the anoxic zone is installed with an online ammonia nitrogen and nitric nitrogen meter 84, and the output end of the disinfection unit is installed with an outlet total nitrogen online monitor 85; the output end of the aerobic zone is connected to the input end of the anoxic zone; the carbon source addition unit is connected to the input end of the anoxic zone; the feedback compensation module is connected to the output end of the anoxic zone; the water inlet pretreatment unit is connected to the input end of the anaerobic zone; the terminal verification module input is communicatively connected to the output end of the disinfection unit.

[0057] In this embodiment, the online ammonia nitrogen and nitric nitrogen meter 84 is used to monitor the ammonia nitrogen and nitric nitrogen concentrations in the effluent of the anoxic zone, and the outlet total nitrogen online monitor 85 is used to monitor the total nitrogen concentration in the dischargeable water after all sewage treatment steps.

[0058] Furthermore, the water inlet end of the water inlet monitoring and pretreatment module is equipped with a flow meter 81 and a water inlet COD Cr Online monitor 82 and total nitrogen online monitor 83 at the water inlet end.

[0059] In this embodiment, the flow meter 81 is used to measure the influent water volume. Cr The online monitor 82 and the inlet total nitrogen online monitor 83 are used to monitor the inlet COD cr , total nitrogen pollutant concentration.

[0060] Furthermore, the carbon source dosing unit includes a dosing pump, a dosing pump frequency converter, a dosing flow meter 86 and a drug storage bin; the dosing flow meter 86 is installed at the output end of the dosing pump; the output end of the dosing pump frequency converter and the drug storage bin are both connected to the input end of the dosing pump, the output end of the dosing pump is installed with a dosing flow meter, and the carbon source dosage control module and the input end of the dosing pump frequency converter are both communicatively connected to the output end of the dosing pump; the input end of the dosing pump frequency converter is communicatively connected to the output end of the carbon source dosage control module.

[0061] Based on the above embodiments, Figure 1 The modules in can be more specifically expressed as Figure 2 shown.

[0062] Embodiment 2:

[0063] Now, based on the specific description of each step of the operation control method of the carbon source automatic dosing system in Example 1, a specific description is given in combination with an actual sewage treatment plant:

[0064] A certain city sewage treatment plant adopts fine screen + cyclone sand settling process for pretreatment, improved Carrousel2000 oxidation ditch + secondary sedimentation tank process for sewage treatment, high density pool + filter cloth filter process for deep treatment, ultraviolet disinfection process for tail water, and the design scale is 20,000 tons / day. The C / N ratio of the sewage plant influent is 4-4.5, and the total nitrogen in the influent can reach 60mg / L when it is high. The problem of C / N ratio imbalance exists for a long time. In order to ensure that the total nitrogen in the effluent meets the standard, it is necessary to add an external carbon source. The carbon source addition is manually adjusted by the central control personnel through observing the inlet and outlet water quality. Flow meters and water quality online monitors have been installed at the inlet and outlet of the sewage plant, and carbon source addition units have been installed at the inlet of the anoxic zone. The relevant data have been transmitted to the central control system of the sewage plant. An online ammonia nitrogen and nitrate nitrogen meter is installed at the inlet of the anoxic zone, and the corresponding control modules of the feedforward module, feedback compensation module and terminal calibration module are implanted in the central control computer of the sewage plant. The carbon source addition control system program has the authority to read the data of the central control system of the sewage plant computer.

[0065] (1) Determine the amount of carbon source feedforward

[0066] Input the feedforward carbon source dosage calculation formula into the feedforward module and set the relevant parameter values:

[0067]

[0068] In the formula, the external carbon source dosage q 1 For the calculation and output index of the feedforward module, the initial value of the carbon source addition coefficient m is set to 6; the total nitrogen concentration of the influent A i-TN 、Influent COD Cr Concentration COD Cr-i、 Inlet flow Q c Read from the computer control system of the sewage treatment plant. The sewage treatment plant uses glacial acetic acid with a purity of more than 99% as the carbon source. The mass concentration w of the carbon source solution is close to the density of glacial acetic acid, which is 1.049×10 6 mg / L, pure glacial acetic acid COD equivalent COD eq The COD is 1.067mg / mg. 3 / h, influent COD Cr Taking the total nitrogen content of 200mg / L and the total nitrogen of 45mg / L in influent as an example, the carbon source dosage calculated by the feedforward module is 39.2L / h, and the calculation result is output to the carbon source dosage control module. The carbon source dosage control module automatically doses the drug according to the dosage given by the feedforward module by simulating the relationship between the frequency of the inverter and the flow rate of the dosing pump. It is worth noting that the subsequent feedback compensation module may adjust the carbon source dosage, so the actual carbon source dosage is the superposition of the dosage output by the feedforward calculation and the feedback compensation dosage.

[0069] The online water quality of the sewage treatment plant's influent is updated every hour, so the feedforward carbon source dosage calculation is performed every hour. When the calculation result deviates by more than 15% compared with the previous cycle, the carbon source dosage adjustment is triggered. During each cycle calculation, the feedforward module will reversely deduce the corrected dosage coefficient m based on the actual dosage corrected by feedback compensation.

[0070] (2) Determine the carbon source feedback compensation amount

[0071] The total nitrogen discharge standard of the sewage plant is 15 mg / L, and the total nitrogen threshold A is set. O-TN It is 13 mg / L. According to the long-term operation monitoring data of the sewage plant, the total nitrogen concentration in the sewage plant effluent is generally higher than the ammonia nitrogen concentration in the anoxic zone effluent. H , Nitrate nitrogen concentration A O The sum of A HO is about 1.5 mg / L lower, so the A 1 The value is 1.5mg / L, that is, A HO Set to 14.5mg / L.

[0072] The online ammonia nitrogen and nitrate nitrogen meter installed at the outlet of the anoxic zone obtains the real-time values ​​of ammonia nitrogen and nitrate nitrogen in the effluent of the anoxic zone in real time. When the sum of the real-time values ​​of ammonia nitrogen and nitrate nitrogen in the effluent of the anoxic zone is equal to the total concentration threshold A of ammonia nitrogen and nitrate nitrogen, the HO When the difference is lower than -1mg / L or higher than 1mg / L for more than 20 minutes, negative feedback supplement and positive feedback compensation are performed respectively. The compensation method is that the feedback compensation module gives the carbon source dosage control module a frequency reduction or increase. The carbon source dosage control module adjusts the frequency of the dosing pump inverter according to the given signal and then adjusts the carbon source dosage. The frequency increase or decrease amplitude of the inverter is initially set to 2Hz. The subsequent system self-learning summarizes the sum of the online real-time values ​​of ammonia nitrogen and nitric nitrogen in the effluent and the total concentration threshold A of ammonia nitrogen and nitric nitrogen. HO The deviation size and the corresponding frequency size that need to be adjusted are automatically adjusted.

[0073] According to the observation results, after each feedback compensation adjustment of the dosage, the sum of the real-time values ​​of ammonia nitrogen and nitric nitrogen in the effluent of the anoxic zone stabilized again after about 0.5 hours. Therefore, the feedback compensation adjustment of the dosage was set to observe for 0.5 hours, and then the above analysis steps were repeated to determine whether the feedback compensation dosage should be adjusted again.

[0074] (3) End-point calibration adjustment feedback compensation control

[0075] The terminal verification module reads the total nitrogen concentration value of the sewage plant effluent from the central control system in real time and compares it with the effluent total nitrogen threshold value A. O-TN When the real-time value of total nitrogen in the effluent is compared with the threshold value of total nitrogen in the effluent A O-TNWhen the difference is lower than -0.5mg / L or higher than 0.5mg / L for more than 20 minutes, the terminal calibration module will give a feedback compensation signal, and the feedback compensation module will adjust A 1 Value, that is, to adjust the total concentration threshold A of ammonia nitrogen and nitrate nitrogen in the effluent of the anoxic zone HO , through the total concentration threshold A HO The change of carbon source feedback compensation dosage is adjusted to ensure the stability of the total nitrogen concentration in the effluent, such as the original effluent total nitrogen threshold A O-TN 13mg / L, A 1 The value is 1.5mg / L (i.e. A HO The control value is 14.5mg / L, and the actual effluent total nitrogen has reached 14mg / L for more than 20 minutes. At this time, without changing the effluent total nitrogen threshold value A O-TN Under the condition of 13mg / L, the terminal calibration module should give the feedback compensation module to reduce A 1 The signal value is 0.5 mg / L (the total concentration threshold A of the total ammonia nitrogen and nitrate nitrogen concentrations in the anoxic zone effluent HO Adjusted to 13.5mg / L).

[0076] The actual operation effect of the system is shown in Table 1. Through technical transformation, the total nitrogen content of the sewage treatment plant effluent has been stably up to standard and can be controlled at a higher level. Compared with the original dosage adjusted by the central control personnel, the carbon source dosage has been reduced by more than 26%.

[0077] Table 1 Comparison of operating effects before and after technical transformation

[0078]

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A carbon source automatic dosing system, characterized in that: It includes an inlet monitoring and pretreatment module, a sewage treatment assembly module, a carbon source dosage control module, a carbon source addition unit, a feedforward module, a feedback compensation module and a terminal verification module; the inlet monitoring and pretreatment module is connected to the input end of the sewage treatment assembly module; the output ends of the feedforward module and the feedback compensation module are both communicatively connected to the input end of the carbon source dosage control module; the input end of the feedforward module is communicatively connected to the output end of the inlet monitoring and pretreatment module; the input end of the feedback compensation module is communicatively connected to the output end of the sewage treatment assembly module and the output end of the terminal verification module respectively; the input end of the terminal verification module is communicatively connected to the output end of the sewage treatment assembly module; the input end of the carbon source addition unit is communicatively connected to the output end of the carbon source dosage control module, and the output end is connected to the sewage treatment assembly module; The inlet monitoring and pretreatment module is used to monitor the inlet volume and the concentration of pollutants in the inlet water, and pretreat the pollutants in the sewage based on the subsequent sewage treatment steps; the sewage treatment assembly module is used for sewage treatment and disinfection; the feedforward module is used to predict the dosage of the carbon source according to the inlet volume and the concentration of pollutants in the inlet water; the feedback compensation module is used to adjust the dosage of the carbon source of the feedforward module; the terminal verification module is used to test the pollutant content in the final sewage and adjust the adjustment amount of the feedback compensation module; the carbon source dosage control module is used to control the action of the carbon source addition unit according to the test results of the feedforward module, the feedback compensation module and the terminal verification module; the carbon source addition unit is used to receive the action signal of the carbon source dosage control module and add the carbon source to the sewage treatment assembly module.

2. The carbon source automatic dosing system according to claim 1, characterized in that: The sewage treatment assembly module comprises an anaerobic zone, an anoxic zone, an aerobic zone, a secondary sedimentation tank, a deep treatment unit and a disinfection unit, and the anaerobic zone, the anoxic zone, the aerobic zone, the secondary sedimentation tank, the deep treatment unit and the disinfection unit are connected in sequence; the output end of the anoxic zone is equipped with an online ammonia nitrogen and nitrate nitrogen meter (84), and the output end of the disinfection unit is equipped with an outlet end total nitrogen online monitor (85); the output end of the aerobic zone is connected to the input end of the anoxic zone; the carbon source addition unit is connected to the input end of the anoxic zone; the feedback compensation module is connected to the output end of the anoxic zone; the water inlet monitoring and pretreatment module is connected to the input end of the anaerobic zone; and the terminal verification module input is communicatively connected to the output end of the disinfection unit.

3. The carbon source automatic dosing system according to claim 1, characterized in that: The water inlet end of the water inlet monitoring and pretreatment module is equipped with a flow meter (81), a water inlet COD Cr An online monitor (82) and an online monitor (83) for total nitrogen at the water inlet.

4. The carbon source automatic dosing system according to claim 1, characterized in that: The carbon source dosing unit comprises a dosing pump, a dosing pump frequency converter, a dosing flow meter (86) and a drug storage bin; the dosing flow meter (86) is installed at the output end of the dosing pump; the output end of the dosing pump frequency converter and the drug storage bin are both connected to the input end of the dosing pump, the output end of the dosing pump is equipped with a dosing flow meter, and the carbon source dosing amount control module and the input end of the dosing pump frequency converter are both communicatively connected to the output end of the dosing pump; the input end of the dosing pump frequency converter is communicatively connected to the output end of the carbon source dosing amount control module.

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