Enhanced denitrification dosing method and system based on oxidation ditch

Abstract

The invention provides an enhanced denitrification dosing method and system based on an oxidation ditch, and belongs to the technical field of sewage treatment.The method comprises the steps that the total carbon source amount needing to be put is determined based on a first coefficient and a second coefficient; the first coefficient is a C / N ratio required to be added into the sewage; the second coefficient is the ratio of degradable COD to total COD in the sewage; on the basis of the first coefficient, the second coefficient and the total carbon source amount, the dosage corresponding to the outer ditch dosing pump and the dosage corresponding to the middle ditch dosing pump are calculated; according to the first judgment condition, whether the outer ditch dosing pump and the middle ditch dosing pump start dosing or not is determined; and controlling the outer ditch dosing pump and the middle ditch dosing pump to respectively carry out dosing according to the corresponding dosing amounts according to the second judgment condition. According to the enhanced denitrification dosing method and system based on the oxidation ditch provided by the invention, accurate control on the carbon source feeding position and the carbon source feeding amount can be realized.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of sewage treatment, and more specifically, relates to an enhanced denitrification dosing method and system based on an oxidation ditch. Background Art

[0002] The Orbel oxidation ditch is a variation of the activated sludge process. Because the mixture of sewage and activated sludge flows continuously in the annular aeration channel, it is called a "circulating aeration tank" or "endless aeration system". The Orbel oxidation ditch is generally composed of three concentric circular or elliptical channels, which are connected to each other. In the three-channel system, from the outside to the inside, they are called the outer ditch, the middle ditch and the inner ditch. Sewage and return sludge (external return) enter from the outer ditch, then enter the middle ditch and finally enter the inner ditch, circulate in each ditch for dozens to hundreds of times, and finally flow out to the secondary sedimentation tank through the adjustable weir gate of the central island. The Orbel oxidation ditch is equipped with different numbers of aeration equipment (aeration disc machine) across each ditch to provide oxygen and have a strong plug flow stirring effect. Generally, during operation, the dissolved oxygen in the three ditches from the outside to the inside is distributed in a gradient of 0-1-2 mg / L.

[0003] refer to Figure 1 The main forms of nitrogen pollutants in sewage are organic nitrogen and ammonia nitrogen, and their removal is mainly completed by three reactions: ammoniation, nitrification and denitrification. The ammoniation reaction is mainly the decomposition and conversion of organic nitrogen compounds into ammonia nitrogen by ammonifying bacteria; the nitrification reaction is the process in which autotrophic bacteria, mainly nitrite bacteria and nitrate bacteria, convert ammonia nitrogen into nitrite nitrogen and nitrate nitrogen under an aerobic environment; the denitrification reaction is the process in which nitrite nitrogen and nitrate nitrogen are reduced to nitrogen gas by heterotrophic denitrifying bacteria.

[0004] Among them, Table 1 shows the conditions that affect microbial denitrification. As shown in Table 1, the main factors affecting the denitrification effect in the sewage treatment process are dissolved oxygen content, pH value and alkalinity, carbon source input and temperature, among which the carbon source input is the main influencing factor affecting the denitrification reaction.

[0005] Table 1 Conditions affecting microbial denitrification

[0006] In order to effectively remove nitrogen pollutants in sewage, it is usually necessary to accurately control the amount of carbon source added during nitrification and denitrification reactions. At present, most sewage treatment plants have various methods for studying carbon source addition systems and calculating carbon source addition amounts, but there is a common problem of delayed adjustment of carbon placement positions, and it is impossible to clearly define the basis for carbon source addition calculations, thus making it impossible to accurately control carbon addition amounts. Therefore, there is an urgent need for an enhanced denitrification dosing method and system based on an oxidation ditch. Summary of the invention

[0007] The purpose of the present disclosure is to provide an enhanced denitrification dosing method and system based on an oxidation ditch to solve the problem of precise control and accurate calculation of the amount of carbon source added during sewage treatment.

[0008] In a first aspect of the embodiments of the present disclosure, a method for enhancing denitrification and dosing based on an oxidation ditch is provided, comprising: The total amount of carbon source to be added is determined based on the first coefficient and the second coefficient; the first coefficient is the C / N ratio to be added in the sewage; the second coefficient is the degradable COD / total COD ratio in the sewage; Based on the first coefficient, the second coefficient, and the total carbon source amount, calculate the dosage corresponding to the outer groove dosing pump and the middle groove dosing pump respectively; Determine whether the outer groove dosing pump and the middle groove dosing pump start dosing according to the first judgment condition; According to the second judgment condition, the outer groove dosing pump and the middle groove dosing pump are controlled to add drugs according to the corresponding dosing amounts.

[0009] A second aspect of the disclosed embodiment provides an enhanced denitrification dosing device based on an oxidation ditch, comprising: A prediction module, for determining the total amount of carbon source to be added based on a first coefficient and a second coefficient; the first coefficient is the C / N ratio to be added to the sewage; the second coefficient is the degradable COD / total COD ratio in the sewage; A calculation module, used for calculating the dosage corresponding to the outer groove dosing pump and the middle groove dosing pump respectively based on the first coefficient, the second coefficient, and the total carbon source amount; A first judgment module is used to determine whether the outer groove dosing pump and the middle groove dosing pump start dosing according to a first judgment condition; The second judgment module is used to control the outer groove dosing pump and the middle groove dosing pump to add drugs according to corresponding dosing amounts according to the second judgment condition.

[0010] The third aspect of the embodiments of the present disclosure provides an enhanced denitrification dosing system based on an oxidation ditch, comprising: an online monitoring instrument, a control system, a carbon source dosing system and an electronic device; the electronic device comprises a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of the above-mentioned enhanced denitrification dosing method based on an oxidation ditch when executing the computer program.

[0011] According to a fourth aspect of the embodiments of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above-mentioned enhanced denitrification dosing method based on oxidation ditch are implemented.

[0012] The beneficial effects of the enhanced denitrification dosing method and system based on the oxidation ditch provided by the embodiments of the present disclosure are: First, the disclosed embodiment can introduce the relevant first coefficient and second coefficient into the carbon source addition calculation method, adjust the first coefficient and the second coefficient in advance according to different water inlet conditions and the first monitoring data obtained from sewage monitoring, and achieve precise regulation of the carbon source dosage through the adjustment of the coefficients, thereby ensuring that the calculation of the carbon source dosage is completed before the system effluent exceeds the standard, avoiding the problem of adjustment lag, improving the control accuracy of the carbon source dosage, and ensuring the full implementation of the denitrification reaction of the system.

[0013] Second, the disclosed embodiment can realize the dosing control of the outer ditch dosing pump and the middle ditch dosing pump respectively through the second judgment condition. When the system effluent is stable and the concentration of pollutants in the sewage is low, the carbon source dosage is reduced or even stopped in time to avoid water safety accidents caused by excessive water quality drug concentration. At the same time, it can also reduce operating expenses and reduce operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, 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 some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 A diagram of the denitrification mechanism of a biochemical pool provided in one embodiment of the present disclosure; Figure 2 A schematic flow diagram of an enhanced denitrification dosing method based on an oxidation ditch provided in one embodiment of the present disclosure; Figure 3 A schematic diagram of a feedback adjustment unit of a control system provided in an embodiment of the present disclosure; Figure 4 A detailed schematic diagram of a dosing method provided in one embodiment of the present disclosure; Figure 5 A structural block diagram of an enhanced denitrification dosing device based on an oxidation ditch provided in one embodiment of the present disclosure; Figure 6 A partial structural schematic diagram of an enhanced denitrification dosing system based on an oxidation ditch provided in one embodiment of the present disclosure; Figure 7 A schematic block diagram of an electronic device provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0016] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present disclosure. However, it should be clear to those skilled in the art that the present disclosure may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present disclosure with unnecessary details.

[0017] In order to make the purpose, technical solutions and advantages of the present disclosure more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0018] Please refer to Figure 2 , Figure 2 A schematic flow diagram of an enhanced denitrification dosing method based on an oxidation ditch provided in one embodiment of the present disclosure, the method comprising: S101: Determine the total amount of carbon source that needs to be added based on the first coefficient and the second coefficient; the first coefficient is the C / N ratio that needs to be added to the sewage; the second coefficient is the degradable COD / total COD ratio in the sewage.

[0019] This embodiment can analyze the conditions affecting denitrification, nitrification and denitrification reactions, and by setting up a variety of monitoring equipment in the oxidation ditch, the first monitoring data is obtained to achieve accurate calculation of the total carbon source input. For example, a real-time online water quality monitoring device is set in the oxidation ditch, mainly including DO, alkalinity, ammonia nitrogen, nitrate nitrogen, etc. to grasp the water quality in real time, and provide feedback to the carbon source addition system for real-time adjustment. Set the position and monitoring indicators: install online instruments for dissolved oxygen, ammonia nitrogen and nitrate nitrogen in the outer ditch; install online instruments for dissolved oxygen, alkalinity, ammonia nitrogen and nitrate nitrogen in the inner ditch, and combine the COD and inlet flow meters of the sewage treatment plant to monitor the denitrification effect of the oxidation ditch in real time and provide feedback.

[0020] According to the analysis of the first monitoring data, the most suitable carbon-nitrogen ratio (C / N) for denitrification reaction in the current water quality, i.e. the first coefficient, is determined; as well as the most suitable degradable COD / total COD ratio, i.e. the second coefficient. COD concentration refers to the amount of oxygen required for organic matter to be oxidized by chemical oxidants in a certain volume of water sample, usually expressed in milligrams per liter (mg / L). Based on the currently determined first and second coefficients, the total amount of carbon source to be put in can be predicted, so that the corresponding amount of put in can be configured in advance to avoid the problem of delayed regulation of carbon source put in due to the time difference in the water inlet process, which affects the precise control of carbon source put in and leads to low sewage treatment efficiency.

[0021] S102: Calculate the dosages corresponding to the outer groove dosing pump and the middle groove dosing pump respectively based on the first coefficient, the second coefficient, and the total carbon source amount.

[0022] In this embodiment, the outer ditch dosing pump is a dosing pump arranged in the outer ditch, and the middle ditch dosing pump is a dosing pump arranged in the middle ditch. The dosing amount corresponding to the outer ditch dosing pump and the middle ditch dosing pump can be calculated according to the first coefficient, the second coefficient and the total carbon source, and the dosing control process of the oxidation ditch enhanced denitrification is realized according to the dosing amount.

[0023] S103: Determine whether the outer groove dosing pump and the middle groove dosing pump start dosing according to the first judgment condition.

[0024] In this embodiment, a first judgment condition is set to control whether the outer groove dosing pump and the middle groove dosing pump start dosing, wherein the first judgment condition can be calculated based on the first coefficient and the second coefficient. This embodiment provides a reference example, and the first judgment condition can be set as: >0, start the carbon source dosing pump. is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent; is the second coefficient; is the influent COD concentration; is the effluent COD concentration.

[0025] S104: According to the second judgment condition, the outer groove dosing pump and the middle groove dosing pump are controlled to add drugs according to corresponding dosing amounts.

[0026] In this embodiment, the outer ditch volume of the traditional Orbel oxidation ditch is about 50% to 55% of the total volume. The sewage stays in the outer ditch for a long time, and its dissolved oxygen is controlled at 0-0.5 mg / L. By forming an alternating aerobic and anoxic environment, the nitrification reaction and the denitrification reaction can be completely realized simultaneously; the dissolved oxygen in the middle ditch is controlled at 0.5-1.5 mg / L, which can further complete the nitrification reaction; the inner ditch volume is small, accounting for about 15% to 20% of the total volume, and its dissolved oxygen is controlled at 2-2.5 mg / L, mainly for aerobic nitrification reaction. Such a dissolved oxygen distribution makes the Orbel oxidation ditch have better denitrification performance. However, in actual situations, since the Orbel oxidation ditch is a surface aeration disc machine that controls dissolved oxygen, its control ability is limited, and it is difficult for the outer ditch to form an alternating aerobic and anoxic environment, so it will have a greater impact on the denitrification reaction.

[0027] In this embodiment, the traditional Obel oxidation ditch is modified to control the dissolved oxygen in the outer ditch to 0-1 mg / L, and to achieve nitrification and denitrification reactions simultaneously; the dissolved oxygen in the middle ditch is controlled to be in a completely anoxic state, and the denitrification reaction is carried out here. In addition, this embodiment sets a second judgment condition to control the outer ditch dosing pump and the middle ditch dosing pump to add drugs according to the corresponding dosing amount. Therefore, the corresponding amount of drugs can be added to the outer ditch and the middle ditch according to the actual reaction situation to achieve the best denitrification effect.

[0028] It can be concluded from the above that this embodiment can achieve precise control of the carbon source placement position by improving the traditional oxidation ditch, and the total carbon source placement amount required for the outer ditch and the middle ditch can be calculated through the first coefficient and the second coefficient, avoiding the problem of delayed dosage adjustment and affecting the control accuracy. The time nodes of the outer ditch dosing pump and the middle ditch dosing pump switch are determined according to the first judgment condition, and the carbon source placement amount is precisely controlled according to the second judgment condition, thereby achieving the effect of enhanced denitrification.

[0029] In one embodiment of the present disclosure, controlling the outer groove dosing pump and the middle groove dosing pump to add drugs according to corresponding dosing amounts according to the second judgment condition includes: In response to the first parameter being greater than or equal to the first threshold, the outer channel dosing pump and the middle channel dosing pump are controlled to dosing according to the first preset value. The first parameter is the pollutant content in the inner channel.

[0030] In response to the first parameter being less than the first threshold and greater than the second threshold, the outer groove dosing pump and the middle groove dosing pump are controlled to dosing according to the outer groove dosing amount and the middle groove dosing amount, respectively. The first threshold is greater than the second threshold. The outer groove dosing amount is the dosing amount corresponding to the outer groove dosing pump. The middle groove dosing amount is the dosing amount corresponding to the middle groove dosing pump.

[0031] In response to the first parameter being less than or equal to the second threshold, the outer channel dosing pump is turned off, and the middle channel dosing pump is controlled to dosing according to a second preset value, which is less than the first preset value.

[0032] In response to the first parameter being less than or equal to the third threshold, the outer channel dosing pump and the middle channel dosing pump are turned off. The second threshold is greater than the third threshold.

[0033] In this embodiment, the first parameter is a parameter used to determine whether the nitrogen concentration of the sewage in the current inner ditch reaches the second determination condition. The first parameter can be expressed as: ,in, is the ammonia nitrogen concentration in the inner ditch, in mg / L, is the nitrate nitrogen concentration in the inner ditch, in mg / L. The first threshold is the maximum limit of the total nitrogen concentration in the effluent, in mg / L, determined according to the control value of the total nitrogen in the effluent, and generally 1-2 mg / L lower than the control value. The second threshold is the guaranteed value of the total nitrogen concentration in the effluent, in mg / L, determined according to the control value of the total nitrogen in the effluent, and generally 3-4 mg / L lower than the control value. The first threshold is greater than the second threshold. The third threshold controls the minimum value of the total nitrogen concentration in the effluent, in mg / L, determined according to the control value of the total nitrogen in the effluent, and generally 5-7 mg / L lower than the control value. The second threshold is greater than the third threshold. The process of adding drugs to the outer ditch dosing pump and the middle ditch dosing pump according to the corresponding dosing amounts according to the second judgment condition can be described in detail as: When the first parameter is greater than or equal to the first threshold, it means that the nitrogen concentration in the inner groove has reached a certain severity, and the outer groove dosing pump and the middle groove dosing pump are controlled to dosing according to the first preset value. The first preset value can be determined by multiple experiments.

[0034] When the first parameter is less than the first threshold and greater than the second threshold, the nitrogen concentration in the inner groove begins to decrease, and the outer groove dosing pump and the middle groove dosing pump can be controlled to add medicine according to the corresponding normal dosing amount, which is the dosing amount calculated according to the first coefficient and the second coefficient.

[0035] When the first parameter is less than or equal to the second threshold, it means that the nitrogen concentration in the inner ditch has dropped significantly, and the outer ditch dosing pump can be controlled to be turned off, and the middle ditch dosing pump can be controlled to dosing according to the second preset value to reduce the dosage and prevent the effluent water quality from exceeding the drug content. The second preset value can also be determined by multiple experiments, and the second preset value is less than the first preset value.

[0036] When the first parameter is less than or equal to the third threshold, it means that the nitrogen concentration in the inner groove has dropped below the safety threshold and no further dosing is needed. Then the outer groove dosing pump and the middle groove dosing pump are controlled to be closed to stop the dosing process.

[0037] From the above, it can be concluded that the present embodiment can accurately control the dosing dosage and switching time of the middle ditch dosing pump and the outer ditch dosing pump through the second judgment condition, and realize the switching coordination between the two dosing pumps, which can respond to the denitrification effect and condition changes in real time, and adjust the carbon source dosage in time according to the feedback to prevent excessive dosing, thereby improving the accuracy of dosing control.

[0038] In one embodiment of the present disclosure, the first threshold is determined based on the total nitrogen discharge of the effluent water, and the second threshold and the third threshold are determined based on the total nitrogen situation of the effluent water.

[0039] The first threshold is determined based on the total nitrogen discharge in the effluent and a first formula; the first formula is:

[0040] The determining the second threshold and the third threshold based on the total nitrogen situation of the effluent water comprises: The second threshold is determined based on the total nitrogen content of the effluent and the second formula; the second formula is:

[0041] The third threshold is determined based on the total nitrogen content of the effluent and the third formula; the third formula is:

[0042] Where A represents the first threshold, B represents the second threshold, represents the third threshold, Indicates the total nitrogen discharge into the water, It represents the average value of effluent total nitrogen (for example, the average value of effluent total nitrogen in the past year), t is estimated according to the normal distribution of the data, and is obtained by looking up the t distribution table; represents the sample standard deviation, and n represents the total sample size.

[0043] In one embodiment of the present disclosure, reference Figure 3 , Figure 3 A schematic diagram of a feedback regulation unit of a control system provided in an embodiment of the present disclosure. The feedback regulation unit includes a PID, an electric stroke controller, a dosing pump, and a flow meter. The PID is connected to the electric stroke controller, which is connected to the dosing pump. The flow meter is used to detect the flow rate of the liquid output by the dosing pump and feed back the collected data to the input end of the PID. The PID sends instructions to the electric stroke controller based on the judgment result, and the electric stroke controller controls the stroke range of the corresponding dosing pump, thereby realizing feedback regulation.

[0044] In one embodiment of the present disclosure, the enhanced denitrification dosing method based on the oxidation ditch further includes: In response to the outer groove dosing pump and the middle groove dosing pump dosing according to the first preset value, controlling the stroke of the dosing pump corresponding to the first preset value based on the first control parameter; In response to the middle channel dosing pump adding chemicals according to the second preset value, the stroke of the dosing pump corresponding to the second preset value is controlled based on the second control parameter.

[0045] In this embodiment, the first control parameter represents the stroke range of the dosing pump (outer groove dosing pump and middle groove dosing pump) corresponding to the first preset value, for example, 90% to 100%; the second control parameter represents the stroke range of the dosing pump (middle groove dosing pump) corresponding to the second preset value, for example, 0% to 10%.

[0046] In one embodiment of the present disclosure, determining the total amount of carbon source to be delivered based on the first coefficient and the second coefficient includes: The first model is trained based on the historical first coefficient, the historical second coefficient, and the total amount of carbon source that needs to be put in historically; the first coefficient and the second coefficient are input into the first model to obtain the total amount of carbon source that needs to be put in.

[0047] In this embodiment, the historical first coefficient and the historical second coefficient can be obtained based on historical monitoring data, which are usually determined artificially. Historical monitoring data refers to historical data for monitoring the concentrations of various pollutants in the oxidation ditch, and the historical monitoring data include monitoring data such as nitrogen concentration content, sewage pH value, sewage temperature, etc. The historical first coefficient refers to the mass ratio of dissolved organic carbon to total nitrogen in sewage with different nitrogen concentrations. The historical second coefficient refers to the ratio of degradable COD / total COD in sewage, that is, the chemical oxygen demand that can be biodegraded in sewage. The total amount of carbon source historically put in is calculated based on the historical first coefficient and the historical second coefficient.

[0048] The first model is trained based on the historical first coefficient, the historical second coefficient, and the total amount of carbon sources that need to be put in historically. The first model can perform matching calculations based on the current first coefficient, the second coefficient, and the total amount of carbon sources put in historically under these two coefficients, so as to predict the total amount of carbon sources that need to be put in currently based on the currently set first coefficient and second coefficient.

[0049] It can be concluded from the above that this embodiment can output the total amount of carbon source that needs to be added according to the prediction model, so that the value of the total carbon source is more accurate, the scientificity and speed of the prediction are improved, and it is beneficial to the advancement of the subsequent dosing process.

[0050] In one embodiment of the present disclosure, the dosage corresponding to the outer channel dosing pump is calculated based on the first coefficient, the second coefficient and the total carbon source amount, including: The dosage of the outer groove is calculated according to the fourth formula; the fourth formula is:

[0051] in, Add medicine to the outer ditch; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

[0052] In this embodiment, in order to accurately control the outer ditch dosing pump to automatically add medicine according to the calculated dosage when the first parameter is less than the first threshold value and greater than the second threshold value, the outer ditch dosage can be calculated by the second formula. The quantitative carbon source delivery to the outer ditch is automatically realized according to the outer ditch dosage, wherein the outer ditch dosage is calculated based on the first coefficient and the second coefficient, and the outer ditch dosage corresponding to different sewage in the denitrification process is calculated according to the prediction results of the first coefficient and the second coefficient. The middle ditch dosage can also be calculated according to the outer ditch dosage, so as to facilitate the simultaneous control of the outer ditch dosing pump and the middle ditch dosing pump to dosing at the same time, so as to realize the enhanced denitrification process of sewage. It can be concluded from the above that the present embodiment can realize the control of the denitrification reaction in the outer ditch by calculating the dosage of the outer ditch, thereby improving the scientificity of the use and the control accuracy of the present embodiment.

[0053] In one embodiment of the present disclosure, the dosage corresponding to the middle channel dosing pump is calculated based on the first coefficient, the second coefficient and the total carbon source amount, including: The dosage of the outer groove is calculated according to the fifth formula; the fifth formula is:

[0054] in, Add medicine to the middle groove; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

[0055] In this embodiment, the dosage of the middle ditch can also be calculated according to the first coefficient and the second coefficient. The dosage of the middle ditch is calculated by the fifth formula to coordinate with the outer ditch to perform the dosing operation synchronously, thereby achieving simultaneous control of nitrification and denitrification reactions and improving reaction efficiency.

[0056] It can be concluded from the above that this embodiment can accurately control the carbon source dosage of the outer groove and the middle groove at the same time, and can also timely reduce the carbon source dosage or even stop the dosage according to the reaction progress, thereby reducing operating costs.

[0057] In one embodiment of the present disclosure, the enhanced denitrification dosing method based on the oxidation ditch also includes: The dosage of the alkalinity chemical is determined based on the first data.

[0058] In this embodiment, according to the influencing factors in Table 1, it can be seen that the influence of sewage alkalinity on nitrification effect cannot be ignored. Generally, most sewage treatment plants will reflect its alkalinity through the pH value of sewage, but in fact, there is a big difference between sewage alkalinity and pH value. pH value directly reflects the H in sewage. + or OH - The alkalinity refers to the total amount of substances in sewage that can neutralize strong acids, except OH - In addition, CO3 2- 、HCO3 - Therefore, it is unreasonable to reflect the alkalinity by pH. Therefore, an alkalinity online monitoring instrument can be added to the inner ditch of the oxidation ditch, and its monitoring results can be recorded and saved in the first monitoring data. According to the first monitoring data obtained, the alkalinity of the sewage in the nitrification stage can be fed back more accurately and in real time to ensure a better nitrification effect.

[0059] In this embodiment, the enhanced denitrification dosing system based on the oxidation ditch also includes an alkalinity dosing system, which controls the dosing amount of the alkalinity drug through real-time alkalinity feedback of the sewage, and can achieve precise control process by setting the alkalinity dosing conditions. For example: (1) When the sewage alkalinity is less than 70, turn on the alkaline chemical dosing pump; (2) When the sewage alkalinity is ≥120, stop the alkaline chemical dosing pump.

[0060] It can be concluded from the above that the present embodiment can also better control the dosage of alkalinity medicine by monitoring the alkalinity of sewage, and better control the progress of nitrification reaction by coordinating the amount of carbon source added, thereby improving the control efficiency.

[0061] In one embodiment of the present disclosure, the enhanced denitrification dosing method and system based on the oxidation ditch provided by the present disclosure are applied in actual sewage treatment scenarios. For example, a sewage treatment plant mainly treats domestic sewage, and the effluent index requires total nitrogen ≤ 10 mg / L. From April 2023 to October 2024, the average value of influent COD was 123 mg / L, of which the degradable COD accounted for 86 mg / L, the average value of influent total nitrogen was 23 mg / L, C / N = 3.7, the influent carbon-nitrogen ratio was low, and the total nitrogen removal was difficult. In October 2023, the enhanced denitrification dosing system based on the oxidation ditch proposed in the present disclosure was used to automatically control the carbon source dosing and the oxidation ditch system operation. From April 2023 to September 2023, the dosing system was not used in the oxidation ditch of the sewage treatment plant. The dosage was adjusted entirely by manual experience and effluent water quality. Sodium acetate was used as the carbon source, and the sodium acetate addition position was the outer ditch of the oxidation ditch. The average amount of sodium acetate added per month was 244 tons. This dosing system will be used from October 2023 to adjust the oxidation ditch system. From October 2023 to February 2024, the sewage treatment plant will operate in winter; from March to September 2024, the temperature is high, which is the summer operation time. The dosing system will be operated from October. According to data statistics, the average dosing amount in winter operation from October to February of the following year is reduced by 188 tons, which is about 30% lower than the previous year when the temperature was high. From March to September 2024, the dosing amount continued to decrease, with an average of 109 tons, a year-on-year decrease of 55%, which has a more obvious effect in reducing drug consumption.

[0062] In one embodiment of the present disclosure, both the outer groove dosing pump and the middle groove dosing pump are mechanical diaphragm pumps that can be adjusted by an eccentric mechanism.

[0063] In this embodiment, the dosing pumps currently used are mainly ordinary diaphragm metering pumps, which are equipped with ordinary constant speed motors. However, when the dosage needs to be reduced, the output torque of such motors will decrease during the frequency reduction process, so overload damage may occur when working at too low a frequency. Therefore, the method of amplifying the motor power is usually adopted to adapt to the requirements of low-frequency work. Long-term work is not only not conducive to metering statistics, but also damages the internal insulation of the electrode. In addition, ordinary metering pumps mainly use specially designed and processed flexible diaphragms to replace pistons, realize reciprocating motion under the action of a driving mechanism, and complete the suction and discharge process. However, this working mode always makes it intermittent when conveying materials, which is extremely unfavorable for the metering, statistics and intelligent control of the dosage, so it is necessary to improve or replace the dosing pump.

[0064] In this embodiment, a mechanical diaphragm pump with an adjustable eccentric mechanism is used, and an external 4-20mA signal is received through an electric stroke controller to adjust the stroke length, thereby achieving smooth and fine adjustment of the dosage.

[0065] As can be seen from the above, this embodiment can achieve intelligent control of the motor by improving the dosing pump method, ensure the smooth progress of the dosing process, improve the dosing efficiency, and also achieve a refined adjustment process and improve the control accuracy.

[0066] In an embodiment of the present disclosure, referring to Figure 4 , the calculation formula value, when the value of this formula is greater than 0, turn on the carbon source dosing pump. Calculate the first parameter Z, , when Z≥A, control the outer ditch dosing pump and the middle ditch dosing pump to dose according to the outer ditch dosing amount and the middle ditch dosing amount respectively, and the stroke of the dosing pump is 90% - 100%. When B<Z<A, the middle ditch and the outer ditch dose simultaneously, where the middle ditch doses according to the fifth formula and the outer ditch doses according to the fourth formula. When Z≤B, the middle ditch starts dosing, the outer ditch is closed, and the middle ditch doses according to 10% of the pump stroke. When Z≤Γ, both the middle ditch and the outer ditch are closed.

[0067] Corresponding to the enhanced denitrification dosing method based on the oxidation ditch in the above embodiment, Figure 5 is the structural block diagram of the enhanced denitrification dosing device based on the oxidation ditch provided by an embodiment of the present disclosure. For the convenience of description, only the parts related to the embodiment of the present disclosure are shown. Referring to Figure 5 , the enhanced denitrification dosing device 20 based on the oxidation ditch includes: a prediction module 21, a calculation module 22, a first judgment module 23, and a second judgment module 24.

[0068] Among them, the prediction module 21 is used to determine the total carbon source amount to be put in based on the first coefficient and the second coefficient; the first coefficient is the C / N ratio to be added in the sewage; the second coefficient is the ratio of biodegradable COD to total COD in the sewage.

[0069] The calculation module 22 is used to calculate the dosing amounts corresponding to the outer ditch dosing pump and the middle ditch dosing pump respectively based on the first coefficient, the second coefficient, and the total carbon source amount.

[0070] The first judgment module 23 is used to determine whether the outer ditch dosing pump and the middle ditch dosing pump start dosing according to the first judgment condition.

[0071] The second judgment module 24 is used to control the outer ditch dosing pump and the middle ditch dosing pump to dose according to the corresponding dosing amounts respectively according to the second judgment condition.

[0072] In an embodiment of the present disclosure, the second judgment module 24 is specifically used for: In response to the first parameter being greater than or equal to the first threshold, control the outer ditch dosing pump and the middle ditch dosing pump to dose according to the first preset value. The first parameter is the inner ditch pollutant content.

[0073] In response to the first parameter being less than the first threshold and greater than the second threshold, the outer groove dosing pump and the middle groove dosing pump are controlled to dosing according to the outer groove dosing amount and the middle groove dosing amount, respectively. The first threshold is greater than the second threshold. The outer groove dosing amount is the dosing amount corresponding to the outer groove dosing pump. The middle groove dosing amount is the dosing amount corresponding to the middle groove dosing pump.

[0074] In response to the first parameter being less than or equal to the second threshold, the outer channel dosing pump is turned off, and the middle channel dosing pump is controlled to dosing according to a second preset value, which is less than the first preset value.

[0075] In response to the first parameter being less than or equal to the third threshold, the outer channel dosing pump and the middle channel dosing pump are turned off. The second threshold is greater than the third threshold.

[0076] In one embodiment of the present disclosure, the prediction module 21 is further used to: The first threshold is determined based on the total nitrogen discharge of the effluent water, and the second threshold and the third threshold are determined based on the total nitrogen situation of the effluent water.

[0077] In one embodiment of the present disclosure, the prediction module 21 is specifically used for: The first threshold is determined based on the total nitrogen discharge in the effluent and a first formula; the first formula is:

[0078] The determining the second threshold and the third threshold based on the total nitrogen situation of the effluent water comprises: The second threshold is determined based on the total nitrogen content of the effluent and the second formula; the second formula is:

[0079] The third threshold is determined based on the total nitrogen content of the effluent and the third formula; the third formula is:

[0080] Where A represents the first threshold, B represents the second threshold, represents the third threshold, Indicates the total nitrogen discharge into the water, It represents the average value of effluent total nitrogen (for example, the average value of effluent total nitrogen in the past year), t is estimated according to the normal distribution of the data, and is obtained by looking up the t distribution table; represents the sample standard deviation, and n represents the total sample size.

[0081] In one embodiment of the present disclosure, the second determination module 24 is further configured to: In response to the outer groove dosing pump and the middle groove dosing pump dosing according to the first preset value, controlling the stroke of the dosing pump corresponding to the first preset value based on the first control parameter; In response to the middle channel dosing pump adding chemicals according to the second preset value, the stroke of the dosing pump corresponding to the second preset value is controlled based on the second control parameter.

[0082] In one embodiment of the present disclosure, the prediction module 21 is also used to: train the first model based on the historical first coefficient, the historical second coefficient, and the historical total amount of carbon source that needs to be put in; input the first coefficient and the second coefficient into the first model to obtain the total amount of carbon source that needs to be put in.

[0083] In one embodiment of the present disclosure, the calculation module 22 is specifically used for: The dosage of the outer groove is calculated according to the fourth formula; the fourth formula is:

[0084] in, Add medicine to the outer ditch; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

[0085] In one embodiment of the present disclosure, the calculation module 22 is specifically used for: The dosage of the outer groove is calculated according to the fifth formula; the fifth formula is:

[0086] in, Add medicine to the middle groove; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

[0087] See also Figure 6 , Figure 6 A partial structural schematic diagram of an enhanced denitrification dosing system based on an oxidation ditch provided in one embodiment of the present disclosure. It can be seen from the figure that the oxidation ditch is divided into an inner ditch, a middle ditch and an outer ditch. The dosing pump 1 in the carbon source dosing system is used to dosing to the middle ditch, and the dosing pump 2 is used to dosing to the outer ditch. The control system can control the working status of the dosing pump 1 and the dosing pump 2. The reagent is stored in a dosing tank connected to the dosing pump 1 and the dosing pump 2 by pipeline. The online monitoring instrument is set in the outer ditch of the oxidation ditch, which is used to monitor the water quality data of the oxidation ditch in real time and judge the denitrification effect. The monitoring instrument can complement the online instrument of the sewage treatment plant to achieve precise control while reducing investment costs.

[0088] See also Figure 7 , Figure 7 A schematic block diagram of an electronic device provided by an embodiment of the present disclosure. Figure 7 The electronic device 300 in the embodiment shown may include: one or more processors 301, one or more input devices 302, one or more output devices 303 and one or more memories 304. The processors 301, input devices 302, output devices 303 and memories 304 communicate with each other via a communication bus 305. The memory 304 is used to store computer programs, which include program instructions. The processor 301 is used to execute the program instructions stored in the memory 304. The processor 301 is configured to call the program instructions to execute the functions of the modules in the above-mentioned device embodiments, such as Figure 5 The functions of modules 21 to 24 are shown.

[0089] It should be understood that in the embodiment of the present disclosure, the processor 301 may be a central processing unit, the input device 302 may include a touch panel, etc., and the output device 303 may include a display, etc. The memory 304 may include a read-only memory and a random access memory, and provide instructions and data to the processor 301. In a specific implementation, the processor 301, the input device 302, and the output device 303 described in the embodiment of the present disclosure may execute the implementation described in the first embodiment and the second embodiment of the enhanced denitrification dosing method based on the oxidation ditch provided in the embodiment of the present disclosure, and may also execute the implementation of the electronic device described in the embodiment of the present disclosure, which will not be repeated here.

[0090] In another embodiment of the present disclosure, a computer-readable storage medium is provided, which stores a computer program, and when the computer program is executed by a processor, the steps of each of the above method embodiments can be implemented. The computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry computer program code, and a USB flash drive.

[0091] The computer-readable storage medium may be an internal storage unit of the electronic device of any of the foregoing embodiments, such as a hard disk or memory of the electronic device. The computer-readable storage medium is used to store computer programs and other programs and data required by the electronic device. The computer-readable storage medium may also be used to temporarily store data that has been output or is to be output.

[0092] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the electronic devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0093] In the several embodiments provided in the present application, it should be understood that the disclosed electronic devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces or units, or it can be an electrical, mechanical or other form of connection.

[0094] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present disclosure.

[0095] In addition, each functional unit in each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0096] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present disclosure, and these modifications or replacements should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A method for enhancing denitrification and dosing based on an oxidation ditch, characterized in that: include: Determine the total amount of carbon source that needs to be put in based on the first coefficient and the second coefficient; The first coefficient is the C / N ratio that needs to be added to the sewage; The second coefficient is the ratio of degradable COD / total COD in sewage; Based on the first coefficient, the second coefficient, and the total carbon source amount, calculate the dosage corresponding to the outer groove dosing pump and the middle groove dosing pump respectively; Determine whether the outer groove dosing pump and the middle groove dosing pump start dosing according to the first judgment condition; According to the second judgment condition, the outer groove dosing pump and the middle groove dosing pump are controlled to add drugs according to the corresponding dosing amounts.

2. The enhanced denitrification dosing method based on oxidation ditch according to claim 1, characterized in that: The controlling the outer groove dosing pump and the middle groove dosing pump to add drugs according to corresponding dosing amounts according to the second judgment condition includes: In response to a first parameter being greater than or equal to a first threshold, controlling the outer groove dosing pump and the middle groove dosing pump to dosing according to a first preset value; the first parameter is the pollutant content in the inner groove; In response to the first parameter being less than the first threshold and greater than the second threshold, the outer groove dosing pump and the middle groove dosing pump are controlled to add drugs according to the outer groove dosing amount and the middle groove dosing amount respectively; the first threshold is greater than the second threshold; the outer groove dosing amount is the dosing amount corresponding to the outer groove dosing pump; the middle groove dosing amount is the dosing amount corresponding to the middle groove dosing pump; In response to the first parameter being less than or equal to a second threshold, the outer channel dosing pump is turned off, and the middle channel dosing pump is controlled to add drugs according to a second preset value; the second preset value is less than the first preset value; In response to the first parameter being less than or equal to a third threshold, the outer channel dosing pump and the middle channel dosing pump are turned off; the second threshold is greater than the third threshold.

3. The enhanced denitrification dosing method based on oxidation ditch according to claim 2, characterized in that: Also includes: The first threshold is determined based on the total nitrogen discharge of the effluent water, and the second threshold and the third threshold are determined based on the total nitrogen situation of the effluent water.

4. The enhanced denitrification dosing method based on oxidation ditch according to claim 3, characterized in that: The determining the first threshold value based on the effluent total nitrogen emission comprises: The first threshold is determined based on the total nitrogen discharge in the effluent and a first formula; the first formula is: The determining the second threshold and the third threshold based on the total nitrogen situation of the effluent water comprises: The second threshold is determined based on the total nitrogen content of the effluent and the second formula; the second formula is: The third threshold is determined based on the total nitrogen content of the effluent and the third formula; the third formula is: Where A represents the first threshold, B represents the second threshold, represents the third threshold, Indicates the total nitrogen discharge into the water, It represents the average value of effluent total nitrogen (for example, the average value of effluent total nitrogen in the past year), t is estimated according to the normal distribution of the data, and is obtained by looking up the t distribution table; represents the sample standard deviation, and n represents the total sample size.

5. The enhanced denitrification dosing method based on oxidation ditch according to claim 2, characterized in that: Also includes: In response to the outer groove dosing pump and the middle groove dosing pump dosing according to the first preset value, controlling the stroke of the dosing pump corresponding to the first preset value based on the first control parameter; In response to the middle channel dosing pump adding medicine according to the second preset value, the stroke of the dosing pump corresponding to the second preset value is controlled based on the second control parameter.

6. The enhanced denitrification dosing method based on oxidation ditch according to claim 1, characterized in that: Calculating the dosage corresponding to the external channel dosing pump based on the first coefficient, the second coefficient and the total carbon source amount includes: The dosage of the outer groove is calculated according to the fourth formula; the fourth formula is: in, Add medicine to the outer ditch; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent water; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

7. The enhanced denitrification dosing method based on oxidation ditch according to claim 1, characterized in that: Calculating the dosage corresponding to the middle channel dosing pump based on the first coefficient, the second coefficient and the total carbon source amount includes: The dosage of the outer groove is calculated according to the fifth formula; the fifth formula is: in, Add medicine to the middle groove; is the first coefficient; is the ammonia nitrogen concentration in the outer ditch; is the nitrate nitrogen concentration in the outer ditch; The target for total nitrogen in effluent water; is the second coefficient; is the influent COD concentration; is the effluent COD concentration; is the water inlet flow rate; is the COD equivalent of the added carbon source; is the unit time of adding carbon source; It is the proportion of carbon source added to the outer ditch to the total carbon source.

8. An enhanced denitrification dosing device based on an oxidation ditch, characterized in that: include: A prediction module, used to determine the total amount of carbon source that needs to be put in based on the first coefficient and the second coefficient; The first coefficient is the C / N ratio that needs to be added to the sewage; The second coefficient is the ratio of degradable COD / total COD in sewage; A calculation module, used for calculating the dosage corresponding to the outer groove dosing pump and the middle groove dosing pump respectively based on the first coefficient, the second coefficient, and the total carbon source amount; A first judgment module is used to determine whether the outer groove dosing pump and the middle groove dosing pump start dosing according to a first judgment condition; The second judgment module is used to control the outer groove dosing pump and the middle groove dosing pump to add drugs according to corresponding dosing amounts according to the second judgment condition.

9. An enhanced denitrification dosing system based on an oxidation ditch, characterized in that: include: An online monitoring instrument, a control system, a carbon source dosing system and an electronic device; the electronic device comprises a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of the method as claimed in any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium storing a computer program, 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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