RBS intelligent control method for adding denitrification filter carbon source and phosphorus removal agent

Abstract

The invention discloses an RBS intelligent control method for adding a carbon source and a phosphorus removal agent of a denitrification filter tank, relates to the technical field of sewage treatment, and can realize accurate adding of an agent and reduce the backwashing frequency of the denitrification filter tank so as to effectively save operation energy consumption and realize green, low-carbon and high-quality operation of a sewage plant. According to the RBS intelligent control method for adding the denitrification filter carbon source and the phosphorus removal agent, carbon source adding comprises the following steps that a control system collects an inlet water flow signal, an inlet water nitrate nitrogen concentration signal, outlet water COD instrument information and filter DO instrument information, and the theoretical carbon source adding amount is calculated through the fuzzy control theory; the actual carbon source adding amount is regularly adjusted through effluent nitro nitrogen concentration signal feedback; the method ensures that NOX-N of the effluent is less than 1mg / L, the addition of the carbon source is not excessive, and the BOD and COD of the effluent are less than those of the influent, and ensures that the TN of the effluent reaches the standard, the accumulation of NO2-N is not generated and the addition of the carbon source is not excessive under the condition that the addition of the carbon source is the lowest.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to an RBS intelligent control method for adding a carbon source and a dephosphorizing agent to a denitrification filter. Background Art

[0002] At present, the A2O process is a commonly used process in municipal sewage treatment plants. The RBS intelligent and precise control can enable water plants to effectively save energy and reduce consumption, save chemicals, and achieve unmanned or low-staff operation, which can significantly reduce the operating costs of sewage plants while ensuring that the effluent quality meets the standards at all times.

[0003] Therefore, how to provide an RBS intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter, which can effectively save reagent costs and operating energy consumption and realize green, low-carbon and high-quality operation of the sewage treatment plant, has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] The object of the present invention is to provide an RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter, which can not only realize the precise addition of agents to effectively save agent costs, but also reduce the backwashing frequency of the denitrification filter while ensuring the effect, thereby effectively saving operating energy consumption, and further realizing the green, low-carbon and high-quality operation of the sewage treatment plant.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme: An RBS intelligent control method for adding carbon source and dephosphorizing agent in a denitrification filter, comprising: adding carbon source and dephosphorizing agent; The carbon source addition comprises the following steps: The control system collects the inlet flow signal, inlet nitrate nitrogen concentration signal, outlet COD instrument information, and filter tank DO instrument information, calculates the theoretical carbon source dosage through fuzzy control theory, and then regularly adjusts the actual carbon source dosage through the outlet nitrate nitrogen concentration signal feedback; Guaranteed water output NO X -N<1mg / L and the carbon source is not excessively added, the effluent BOD and COD are less than the influent, and it is ensured that the effluent TN meets the standard under the condition of the lowest carbon source dosage, and no NO is generated 2 -N accumulation, and no excessive addition of carbon source; There are three control modes for adding the dephosphorization agent: Phosphorus removal agent dosing preselects the "quantitative" operation mode: In the "quantitative" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosing amount to the PAC dosing fixed dosing amount setting value; Phosphorus removal agent dosing preselects the "flow ratio" operation mode: In the "flow ratio" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosage to the calculated dosage value; And, the phosphorus removal agent dosing preselects the "RBS" operating mode: In the "RBS" mode, the PAC dosage is related to the inlet flow rate, the effluent pH measurement value, the inlet phosphate measurement value, the effluent phosphate measurement value and the effluent SS measurement value.

[0006] In practical application, there are three control modes for adding the carbon source: Carbon source addition preselects "quantitative" operation mode; Carbon source addition pre-selects the "flow ratio" operation mode; Carbon source addition pre-selects "RBS" operation mode.

[0007] Wherein, the carbon source addition preselects the "quantitative" operation mode: In the "quantitative" mode, the denitrification filter carbon source dosing and flow signal will be adjusted to adjust the current dosing amount to the set value of the denitrification filter carbon source fixed dosing amount.

[0008] Specifically, the carbon source addition preselects the "flow ratio" operation mode: In the "flow ratio" mode, the carbon source dosing and flow signal of the denitrification filter will be adjusted to adjust the current dosing amount to the calculated dosing amount value; the dosing amount Q 反硝化滤池碳源 Calculated by the following formula:

[0009] Among them, Q 反硝化滤池碳源 is the dosage, unit [l / h]; Q ratio C / N，设定 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the influent, in mgN / l; [NO x总 ] 出，设定 It is the set value of total nitrate nitrogen in effluent, in mgN / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

[0010] Furthermore, the carbon source addition preselects the "RBS" operation mode: In the "RBS" mode, the carbon source dosage of the denitrification filter is related to the inlet flow rate, the effluent COD measurement value, the inlet total nitrate nitrogen measurement value, the effluent total nitrate nitrogen measurement value, and the effluent total nitrate nitrogen set value; the denitrification carbon source dosage Q 反硝化碳源 It is calculated by the following formula:

[0011] Among them, Q 反硝化碳源,RBSis the dosage, unit [l / h]; ratio C / N，设定 is the C / N-nutrient ratio setting value, unit is gCOD / gN; Q 进 is the water inlet flow rate, unit [m³ / h]; [COD] 出 is the measured value of effluent COD, in mgCOD / l; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the denitrification filter influent, in mgN / l; [NO x总 ] 出 is the measured value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [NO x总 ] 出，设定 is the set value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [C] 碳源 It is the set value of effective content of carbon source, in mgC / l; [DO] 反硝化 is the DO measurement value of the denitrification filter, in mg / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

[0012] Furthermore, in order not to exceed the water outlet limit, the calculated dosage will be adjusted by correction factor k; When the water [NO x总 ] concentration exceeds the maximum value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.5; When the water [NO x总 ] concentration is lower than the set value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.0; In between values, the correction factor is adjusted linearly.

[0013] In actual application, the dephosphorization agent is added in the pre-selected "flow ratio" operation mode, and the dosage Q 除磷剂流量 Calculated by the following formula:

[0014] Among them, Q 除磷剂加药 is the dosage, unit [l / h]; Q ratio 除磷剂 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the total phosphate measurement value of the influent, in mgN / l; [PO x总 ] 出，设 is the set value of total phosphate in effluent, in mgN / l; In addition, the flow rate is set to be limited between the minimum PAC dosing flow rate and the maximum PAC dosing flow rate.

[0015] Specifically, in the dephosphorization agent dosing preselected "RBS" operation mode, the dosage Q dephosphorization agent is calculated by the following formula:

[0016] Among them, Q 除磷剂, RBS is the dosage, unit [l / h]; Q 进 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the measured value of phosphate in the influent, in mgP / l; [PO x总 ] 出，设定 is the effluent phosphate set value, in mgP / l; [PO x总 ] 出 is the measured value of phosphate in the effluent, in mgP / l; [P BioP ] is the phosphorus bound by BioP biological phosphorus removal, unit is mgP / l; (M 除磷剂 / M P ) 沉淀 is the necessary chemical reaction stoichiometric ratio, unit: g dephosphorizer / gP; β 沉淀 is the β value, without unit; [Phosphorus removal agent] is the set value of the effective content of the phosphorus removal agent, unit: %; Furthermore, the flow rate is set to be limited between the minimum value of the dephosphorization agent dosing flow rate and the maximum value of the dephosphorization agent dosing flow rate.

[0017] Furthermore, in order not to exceed the water outlet limit, the calculated dosage will be adjusted by a correction factor; When the water [PO x总 ] concentration exceeds the maximum value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.5; when the outlet water [PO x总 ] concentration is lower than the set value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent SS value is higher than the maximum effluent SS value of RBS after adding phosphorus removal agent, the correction coefficient KF SS is 1.2; when the effluent SS value is lower than the effluent SS OK of the phosphorus removal agent RBS, the correction coefficient KF SS is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent pH value is higher than the maximum effluent pH value of RBS after adding phosphorus removal agent, the correction coefficient KF pH is 0.8; when the effluent pH value is lower than the effluent pH value of RBS after phosphorus removal, the correction factor KFpH is 1.0; for values ​​between them, the correction factor is adjusted linearly.

[0018] Compared with the prior art, the RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter of the present invention has the following advantages: In the RBS intelligent control method for adding carbon source and dephosphorizing agent to a denitrification filter provided by the present invention, since the empty bed residence time of the filter is short, usually 15 to 30 minutes, the dosage can be adjusted in time according to the nitrate nitrogen concentration measured in the effluent; the carbon source addition system adopts a feedforward and feedback combination to control the addition of the carbon source, thereby effectively avoiding the situation of too high or too low dosage, so that the dosage meets the removal requirement of TN; the filter can control the addition of the carbon source based on the load of nitrate nitrogen to be removed, that is, the system automatically obtains the inlet flow rate of the filter, combines the inlet and outlet nitrate concentrations of the filter, calculates through the built-in software of the carbon source addition field control cabinet, and issues instructions to control the carbon source dosage of the dosing pump; the carbon source addition control system accurately controls the carbon source dosage through the feedback of the signal of the nitrate concentration meter and the inlet water volume, ensures the minimum methanol dosage, and effectively reduces the operating cost.

[0019] In other words, in the RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter provided by the present invention, accurate addition of carbon source is achieved through the carbon source feedback addition mechanism of the denitrification deep bed filter, thereby avoiding the increase of COD in the filter effluent due to excessive addition of carbon source; that is, accurate carbon source addition is achieved through conversion, thereby ensuring the denitrification effect of the filter while avoiding the risk of increased organic matter in the effluent due to excessive addition of carbon source. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the control principle of RBS dosing of carbon source in a denitrification filter in the RBS intelligent control method for dosing carbon source and dephosphorization agent in a denitrification filter provided in an embodiment of the present invention; Figure 2 A schematic diagram of the identification adaptive control model (MIAC) in the RBS intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The system requires accurate and reliable nitrate analyzers and calibration algorithms to ensure that the carbon source addition is neither too much nor too little, just meeting the design requirements. If too little carbon source is added, the effluent water quality standard cannot be met, and the effluent standard requirement of TN < 10mg / L cannot be met; if too much carbon source is added, the operating cost is high, and there is a possibility that the effluent BOD exceeds the standard; therefore, it is necessary to control the carbon source addition and use a carbon source addition system; and when the deep bed filter is running in the denitrification mode, it is necessary to add an external carbon source to achieve denitrification and denitrification, and the amount of carbon source added directly affects the operating cost and effluent water quality.

[0022] For ease of understanding, the RBS intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter provided by the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings of the specification.

[0023] The embodiment of the present invention provides a RBS intelligent control method for adding carbon source and phosphorus removal agent to a denitrification filter, such as Figure 1 and Figure 2 As shown, it includes: adding carbon source and phosphorus removal agent; The carbon source addition comprises the following steps: The control system collects the inlet flow signal, inlet nitrate nitrogen concentration signal, outlet COD instrument information, and filter tank DO instrument information, calculates the theoretical carbon source dosage through fuzzy control theory, and then regularly adjusts the actual carbon source dosage through the outlet nitrate nitrogen concentration signal feedback; Guaranteed water output NO X -N<1mg / L and the carbon source is not excessively added, the effluent BOD and COD are less than the influent, and it is ensured that the effluent TN meets the standard under the condition of the lowest carbon source dosage, and no NO is generated 2 -N accumulation, and no excessive addition of carbon source; There are three control modes for adding the dephosphorization agent: Phosphorus removal agent dosing preselects the "quantitative" operation mode: In the "quantitative" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosing amount to the PAC dosing fixed dosing amount setting value; Phosphorus removal agent dosing preselects the "flow ratio" operation mode: In the "flow ratio" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosage to the calculated dosage value; And, the phosphorus removal agent dosing preselects the "RBS" operating mode: In the "RBS" mode, the PAC dosage is related to the inlet flow rate, the effluent pH measurement value, the inlet phosphate measurement value, the effluent phosphate measurement value and the effluent SS measurement value.

[0024] When the carbon source dosage is too high, it will increase the carbon source dosage cost and the effluent BOD 5In addition, excessive addition of carbon source will also produce a large number of Bayer sulfur bacteria, which will become a sticky white substance attached to the pool wall, affecting the sensory perception; When the amount of carbon source added is insufficient, the effluent will contain a lot of NO X -N, which can neither ensure that the effluent TN meets the standard nor waste the carbon source. X -N<2mg / L, while NH 3 -N<1.5mg / L, if the effluent organic nitrogen ≤1.5mg / L, the effluent TN can be guaranteed to be<5mg / L.

[0025] In the RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter provided by the embodiment of the present invention, the RBS denitrification intelligent dosing control system can accurately control the effluent NO X -N<2mg / L or below 1mg / L.

[0026] Compared with the prior art, the RBS intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter described in the embodiment of the present invention has the following advantages: In the RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter provided by the embodiment of the present invention, since the empty bed residence time of the filter is short, usually 15 to 30 minutes, the dosage can be adjusted in time according to the nitrate nitrogen concentration measured in the effluent; the carbon source addition system adopts a feedforward and feedback combination to control the addition of the carbon source, thereby effectively avoiding the situation of too high or too low dosage, so that the dosage meets the TN removal requirements; the filter can control the dosage of the carbon source based on the load of nitrate nitrogen to be removed, that is, the system automatically obtains the inlet flow rate of the filter, combines the inlet and outlet nitrate concentrations of the filter, calculates through the built-in software of the carbon source addition field control cabinet, and issues instructions to control the carbon source dosage of the dosing pump; the carbon source addition control system accurately controls the carbon source dosage through the feedback of the nitrate concentration meter and the inlet water volume signal, ensures the minimum methanol dosage, and effectively reduces the operating cost.

[0027] In other words, in the RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter provided by the embodiment of the present invention, accurate addition of carbon source is achieved through the carbon source feedback addition mechanism of the denitrification deep bed filter, thereby avoiding the increase of COD in the filter effluent due to excessive addition of carbon source; that is, accurate carbon source addition is achieved through conversion, thereby ensuring the denitrification effect of the filter while avoiding the risk of increased organic matter in the effluent due to excessive addition of carbon source.

[0028] In practical application, there are three control modes for the above carbon source addition: Carbon source addition preselects "quantitative" operation mode; Carbon source addition pre-selects the "flow ratio" operation mode; Carbon source addition pre-selects "RBS" operation mode.

[0029] Among them, the above-mentioned carbon source addition pre-selects the "quantitative" operation mode: In the "quantitative" mode, the denitrification filter carbon source dosing and flow signal will be adjusted to adjust the current dosing amount to the set value of the denitrification filter carbon source fixed dosing amount.

[0030] Specifically, the above carbon source addition preselects the "flow ratio" operation mode: In the "flow ratio" mode, the carbon source dosing and flow signal of the denitrification filter will be adjusted to adjust the current dosing amount to the calculated dosing amount value; the dosing amount Q 反硝化滤池碳源 Calculated by the following formula:

[0031] Among them, Q 反硝化滤池碳源 is the dosage, unit [l / h]; Q ratio C / N，设定 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the influent, in mgN / l; [NO x总 ] 出，设定 It is the set value of total nitrate nitrogen in effluent, in mgN / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

[0032] Preferably, the inlet flow rate is less than the total inlet flow rate of the plant or the total inlet flow rate of the denitrification filter. In order to prevent the unstable operation of the reflux pump due to the fluctuation of the inlet flow measurement value, the 1-hour average value of the inlet flow rate is used for calculation. When the inlet flow measurement device fails, the outlet flow rate is used to enter the formula to calculate the set value. When the inlet nitrate nitrogen measurement value is less than or equal to the outlet nitrate nitrogen set value, One item is set to 0. When the effluent COD measurement value has an alarm, but the effluent total nitrogen value has no alarm, the denitrification carbon source dosage is set to 0, and the normal dosage is restored after the effluent COD alarm is lifted; when the effluent COD measurement value has an alarm, and the effluent total nitrogen measurement value also has an alarm, the denitrification carbon source dosage is added at the minimum value, and a pop-up window is displayed to remind the operation and maintenance technicians.

[0033] Furthermore, the above carbon source addition preselects the "RBS" operation mode: In the "RBS" mode, the carbon source dosage of the denitrification filter is related to the inlet flow rate, the effluent COD measurement value, the inlet total nitrate nitrogen measurement value, the effluent total nitrate nitrogen measurement value, and the effluent total nitrate nitrogen set value; the denitrification carbon source dosage Q 反硝化碳源 It is calculated by the following formula:

[0034] Among them, Q 反硝化碳源,RBS is the dosage, unit [l / h]; ratio C / N，设定 is the C / N-nutrient ratio setting value, unit is gCOD / gN; Q 进 is the water inlet flow rate, unit [m³ / h]; [COD] 出 is the measured value of effluent COD, in mgCOD / l; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the denitrification filter influent, in mgN / l; [NO x总 ] 出 is the measured value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [NO x总 ] 出，设定 is the set value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [C] 碳源 It is the set value of effective content of carbon source, in mgC / l; [DO] 反硝化 is the DO measurement value of the denitrification filter, in mg / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

[0035] Formula in curly brackets: The first part of the formula takes into account the impact of the total nitrate nitrogen measured value of the denitrification filter influent on the carbon source dosage; the second part of the formula takes into account the impact of the total nitrate nitrogen measured value of the denitrification filter effluent on the carbon source dosage; the third part of the formula takes into account the impact of dissolved oxygen in the denitrification filter on carbon source consumption; the fourth part of the formula takes into account the impact of COD in the denitrification filter effluent on the carbon source dosage. The following situations may occur during actual operation: the total nitrate nitrogen concentration in the effluent is low, while the inlet COD concentration is high, or the total nitrate nitrogen concentration in the effluent is high, while the inlet COD concentration is low. Calculated through the relevant parameters of the sewage treatment plant influent or effluent, if one side of the calculation requires an increase in the carbon source dosage while the other side only requires a small amount of addition, in order to ensure that both feedforward and feedback can effectively perform carbon source dosing, only positive values ​​in each part of the formula can be added, and MAX {0 | XY} is used to achieve positive calculation results for each part of the formula. Proportional C / N，设定 During the debugging process, adjustments are made according to the activity of denitrifying bacteria.

[0036] Furthermore, in order not to exceed the water outlet limit, the calculated dosage will be adjusted by correction factor k; When the water [NO x总 ] concentration exceeds the maximum value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.5; When the water [NO x总 ] concentration is lower than the set value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.0; In between values, the correction factor is adjusted linearly.

[0037] In actual application, in the above phosphorus removal agent addition pre-selected "flow ratio" operation mode, the dosage Q 除磷剂流量 Calculated by the following formula:

[0038] Among them, Q 除磷剂加药 is the dosage, unit [l / h]; Q ratio 除磷剂 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the total phosphate measurement value of the influent, in mgN / l; [PO x总 ] 出，设 is the set value of total phosphate in effluent, in mgN / l; In addition, the flow rate is set to be limited between the minimum PAC dosing flow rate and the maximum PAC dosing flow rate.

[0039] Preferably, the inlet flow rate is measured at the water inlet. In order to prevent the dosing pump from unstable operation due to fluctuations in the measured value of the inlet flow rate, the 1-hour average value of the inlet flow rate is used for calculation. When the inlet flow rate measurement device fails, the outlet flow rate is used to enter the formula to calculate the set value. When the inlet phosphate measurement value is less than or equal to the outlet phosphate set value, One item is set to 0.

[0040] Specifically, in the above-mentioned dephosphorization agent dosing preselection "RBS" operation mode, the dosage Q dephosphorization agent is calculated by the following formula:

[0041] Among them, Q 除磷剂, RBS is the dosage, unit [l / h]; Q 进 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the measured value of phosphate in the influent, in mgP / l; [PO x总 ] 出，设定 is the effluent phosphate set value, in mgP / l; [PO x总 ]出 is the measured value of phosphate in the effluent, in mgP / l; [P BioP ] is the phosphorus bound by BioP biological phosphorus removal, unit is mgP / l; (M 除磷剂 / M P ) 沉淀 is the necessary chemical reaction stoichiometric ratio, unit: g dephosphorizer / gP; β 沉淀 is the β value, without unit; [Phosphorus removal agent] is the set value of the effective content of the phosphorus removal agent, unit: %; Furthermore, the flow rate is set to be limited between the minimum value of the dephosphorization agent dosing flow rate and the maximum value of the dephosphorization agent dosing flow rate.

[0042] Furthermore, in order not to exceed the water outlet limit, the calculated dosage will be adjusted by a correction factor; When the water [PO x总 ] concentration exceeds the maximum value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.5; when the outlet water [PO x总 ] concentration is lower than the set value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent SS value is higher than the maximum effluent SS value of RBS after adding phosphorus removal agent, the correction coefficient KF SS is 1.2; when the effluent SS value is lower than the effluent SS OK of the phosphorus removal agent RBS, the correction coefficient KF SS is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent pH value is higher than the maximum effluent pH value of RBS after adding phosphorus removal agent, the correction coefficient KF pH is 0.8; when the effluent pH value is lower than the effluent pH value of RBS after phosphorus removal, the correction factor KF pH is 1.0; for values ​​between them, the correction factor is adjusted linearly.

[0043] It should be noted here that the principle of denitrification is as follows: denitrification is a biochemical process performed by a group of heterotrophic microorganisms. It is a reaction that reduces nitrite and nitrate to nitrogen gas, nitric oxide or nitrous oxide under anaerobic conditions (no molecular dissolved oxygen). The microorganisms involved in the denitrification process are denitrifying bacteria; denitrifying bacteria are facultative bacteria and are almost ubiquitous in the natural environment. Many common microorganisms in wastewater treatment systems are denitrifying bacteria, such as Proteus, Micrococcus, Pseudomonas, Bacillus, Alcaligenes, Flavobacter, etc. Most of them are facultative bacteria. When dissolved oxygen is present, denitrifying bacteria decompose organic matter using molecular oxygen as the final electron acceptor; in the absence of dissolved oxygen, denitrifying bacteria use N in nitrate and nitrite to decompose organic matter. 5+ and N 3+ As an electron acceptor in energy metabolism, O 2- As a hydrogen acceptor, it generates H 2 O and OH - Alkalinity, organic matter as a carbon source and electron donor to provide energy and be oxidized and stabilized. Among them, the biological denitrification process can be expressed by the following two formulas: 2NO 2 - +6H (electron donor organic matter) → N 2 +2H 2 O +2OH - and 2NO 3 - +9H (electron donor organic matter) → N 2 +3H 2 O +3OH - ; The conversion of nitrite and nitrate in the denitrification process is completed through the assimilation and dissimilation of denitrifying bacteria; assimilation refers to the process in which nitrite and nitrate are reduced to ammonia nitrogen, which is used to synthesize new microbial cells and nitrogen becomes a component of the cytoplasm; dissimilation refers to the process in which nitrite and nitrate are reduced to gaseous substances such as nitrogen, nitric oxide or nitrous oxide, the main component of which is nitrogen, and the nitrogen removed by dissimilation accounts for about 70-75% of the total removal.

[0044] It should be noted that the carbon source addition points of the sewage treatment plant are mainly concentrated in the anoxic zone of the biochemical pool and the water inlet of the deep bed denitrification filter. The method of adding in the anoxic zone of the biochemical pool is described in detail in the invention patent "Intelligent Control Method of RBS for Sewage Treatment Plant, CN114920358B"; this application mainly introduces the intelligent and precise control of carbon source addition at the water inlet of the deep bed denitrification filter.

[0045] In sewage treatment, the denitrification filter is usually used as a unit for deep sewage treatment and is placed at the end of the entire sewage treatment process. When the carbon source of the sewage itself is not sufficient, the carbon source will be used and consumed by the previous process treatment units first, such as the biochemical pool. By the denitrification filter stage, there are usually limited carbon sources or carbon sources that are difficult to bio-utilize. It is difficult to ensure the effect of denitrification and nitrogen removal without adding carbon sources. If too much is added, it is easy to cause the effluent COD to increase instead of decrease, since there are basically no subsequent treatment units, affecting the effluent water quality. Therefore, the precise addition of carbon sources in the denitrification filter is also very important.

[0046] In addition, through the reaction of coagulants with phosphates in sewage, insoluble phosphorus-containing compounds and flocculants are generated, which can separate phosphorus from sewage and achieve the purpose of phosphorus removal. Common coagulants for chemical phosphorus removal include aluminum salts and iron salts. When using filter tank filtration, the micro-flocculation direct filtration method of the denitrification filter is used, and the flocculation and SS interception process is completed by using the unique turbulence effect of the filter tank, which can further remove phosphates; if the denitrification filter tank is overdosed with dephosphorization agents, the filter resistance of the filter tank will increase, and the filter tank will be backwashed frequently. If the dephosphorization agent is too little, it may cause the phosphate in the effluent to exceed the standard, because the addition of dephosphorization agents in the denitrification filter tank also requires intelligent and precise control.

[0047] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter, characterized in that: include: Addition of carbon source and phosphorus removal agent; The carbon source addition comprises the following steps: The control system collects the inlet flow signal, inlet nitrate nitrogen concentration signal, outlet COD instrument information, and filter tank DO instrument information, calculates the theoretical carbon source dosage through fuzzy control theory, and then regularly adjusts the actual carbon source dosage through the outlet nitrate nitrogen concentration signal feedback; Guaranteed water output NO X -N<1mg / L and the carbon source is not excessively added, the effluent BOD and COD are less than the influent, and the effluent TN meets the standard under the condition of the lowest carbon source dosage, without the accumulation of NO2-N and excessive carbon source addition; There are three control modes for adding the dephosphorization agent: Phosphorus removal agent dosing preselection "quantitative" operation mode: In the "quantitative" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosing amount to the PAC dosing fixed dosing amount setting value; Phosphorus removal agent dosing preselection "flow ratio" operation mode: In the "flow ratio" mode, the phosphorus removal agent dosing and flow signals will be adjusted to adjust the current dosing amount to the calculated dosing amount value; And, the phosphorus removal agent dosing pre-selects the "RBS" operating mode: In the "RBS" mode, the PAC dosage is related to the inlet flow rate, the effluent pH measurement value, the inlet phosphate measurement value, the effluent phosphate measurement value and the effluent SS measurement value.

2. The RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter according to claim 1, characterized in that: The control modes of carbon source addition are as follows: Carbon source addition preselection "quantitative" operation mode; Carbon source addition pre-selection "flow ratio" operation mode; Carbon source addition pre-selection "RBS" operation mode.

3. The RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter according to claim 2, characterized in that: The carbon source addition preselects the "quantitative" operation mode: In "Quantitative" mode, the denitrification filter carbon source dosing and flow signal will be adjusted to adjust the current dosing amount to the set value of the denitrification filter carbon source fixed dosing amount.

4. The RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter according to claim 2, characterized in that: The carbon source addition preselected "flow ratio" operation mode: In the "flow ratio" mode, the carbon source dosing and flow signal of the denitrification filter will be adjusted to adjust the current dosing amount to the calculated dosing amount value; Dosing amount Q 反硝化滤池碳源 Calculated by the following formula: Among them, Q 反硝化滤池碳源 is the dosage, unit [l / h]; Q ratio C / N，设定 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the influent, in mgN / l; [NO x总 ] 出，设定 It is the set value of total nitrate nitrogen in effluent, in mgN / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

5. The RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter according to claim 2, characterized in that: The carbon source addition pre-selection "RBS" operation mode: In the "RBS" mode, the carbon source dosage of the denitrification filter is related to the inlet flow rate, the effluent COD measurement value, the inlet total nitrate nitrogen measurement value, the effluent total nitrate nitrogen measurement value, and the effluent total nitrate nitrogen set value; the denitrification carbon source dosage Q 反硝化碳源 It is calculated by the following formula: Among them, Q 反硝化碳源,RBS is the dosage, unit [l / h]; ratio C / N，设定 is the C / N-nutrient ratio setting value, unit is gCOD / gN; Q 进 is the water inlet flow rate, unit [m³ / h]; [COD] 出 is the measured value of effluent COD, in mgCOD / l; [NO x总 ] 进 is the measured value of total nitrate nitrogen in the denitrification filter influent, in mgN / l; [NO x总 ] 出 is the measured value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [NO x总 ] 出，设定 is the set value of total nitrate nitrogen in the effluent of the denitrification filter, in mgN / l; [C] 碳源 It is the set value of effective content of carbon source, in mgC / l; [DO] 反硝化 is the DO measurement value of the denitrification filter, in mg / l; Furthermore, the flow rate is set to be limited between a minimum denitrification carbon source dosing flow rate and a maximum denitrification carbon source dosing flow rate.

6. The RBS intelligent control method for adding carbon source and dephosphorization agent to the denitrification filter according to claim 5, characterized in that: In order not to exceed the water outlet limit, the calculated dosage will be adjusted by correction factor k; When the water [NO x总 ] concentration exceeds the maximum value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.5; When the water [NO x总 ] concentration is lower than the set value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, the correction coefficient k is corrected to 1.0; In between values, the correction factor is adjusted linearly.

7. The RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter according to claim 1, characterized in that: In the operation mode of preselected "flow ratio" for adding the dephosphorization agent, the dosage Q 除磷剂流量 Calculated by the following formula: Among them, Q 除磷剂加药 is the dosage, unit [l / h]; Q ratio 除磷剂 Q is the flow ratio setting value, without unit; 进水 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the total phosphate measurement value of the influent, in mgN / l; [PO x总 ] 出，设 is the set value of total phosphate in effluent, in mgN / l; In addition, the flow rate is set to be limited between the minimum PAC dosing flow rate and the maximum PAC dosing flow rate.

8. The RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter according to claim 1, characterized in that: In the dephosphorization agent dosing preselection "RBS" operation mode, the dosage Q dephosphorization agent is calculated by the following formula: Among them, Q 除磷剂, RBS is the dosage, unit [l / h]; Q 进 is the water inlet flow rate, unit [m³ / h]; [PO x总 ] 进 is the measured value of phosphate in the influent, in mgP / l; [PO x总 ] 出，设定 is the effluent phosphate set value, in mgP / l; [PO x总 ] 出 is the measured value of phosphate in the effluent, in mgP / l; [P BioP ] is the phosphorus bound by BioP biological phosphorus removal, unit is mgP / l; (M 除磷剂 / M P ) 沉淀 is the necessary chemical reaction stoichiometric ratio, unit: g dephosphorizer / gP; β 沉淀 is the β value, without unit; [Phosphorus removal agent] is the set value of the effective content of the phosphorus removal agent, unit: %; In addition, the flow rate is set to be limited between the minimum value of the dephosphorization agent dosing flow rate and the maximum value of the dephosphorization agent dosing flow rate.

9. The RBS intelligent control method for adding carbon source and dephosphorization agent to a denitrification filter according to claim 8, characterized in that: In order not to exceed the water outlet limit, the calculated dosage will be adjusted by the correction factor; When the water [PO x总 ] concentration exceeds the maximum value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.5; when the outlet water [PO x总 ] concentration is lower than the set value of total phosphorus in the RBS effluent after adding phosphorus removal agent, then the correction coefficient KF [P出] is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent SS value is higher than the maximum effluent SS value of RBS after adding phosphorus removal agent, the correction coefficient KF SS is 1.2; when the effluent SS value is lower than the effluent SS OK of the phosphorus removal agent RBS, the correction coefficient KF SS is 1.0; for values ​​in between, the correction coefficient is adjusted linearly; When the effluent pH value is higher than the maximum effluent pH value of RBS after adding phosphorus removal agent, the correction coefficient KF pH is 0.8; when the effluent pH value is lower than the effluent pH value of RBS after phosphorus removal, the correction factor KF pH is 1.0; for values ​​between them, the correction factor is adjusted linearly.

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