Rbs intelligent control method for carbon source and phosphorus removal agent dosing of denitrification filter

Abstract

The application relates to a RBS intelligent control method for carbon source and phosphorus removal agent dosing of a denitrification filter, relates to the technical field of sewage treatment, can realize precise dosing of the agent, can reduce the backwashing frequency of the denitrification filter, thereby effectively saving operation energy consumption, and realizes green, low-carbon and high-quality operation of a sewage plant. In the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter, the carbon source dosing comprises the following steps: a control system collects an inflow flow signal, an inflow nitrate nitrogen concentration signal, outflow COD instrument information and filter DO instrument information, calculates a theoretical carbon source dosing amount through a fuzzy control theory, and regularly adjusts an actual carbon source dosing amount through feedback of an outflow nitro base nitrogen concentration signal; the outflow NO X -N is less than 1 mg / L, the carbon source dosing is not excessive, the outflow BOD and COD are less than the inflow, and under the condition that the carbon source dosing amount is the lowest, the outflow TN meets the standard, NO2-N accumulation is not generated, and carbon source dosing excess is not generated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, and particularly relates to an RBS intelligent control method for carbon source and phosphorus removal agent dosing of a denitrification filter. BACKGROUND

[0002] At present, the A2O process is a commonly used process in municipal sewage treatment plants, and RBS intelligent precise control can effectively save energy and reduce consumption, save drugs, realize unmanned or less manned operation, and greatly reduce the operation cost of the sewage plant while ensuring that the effluent quality meets the standard.

[0003] Therefore, how to provide an RBS intelligent control method for carbon source and phosphorus removal agent dosing of a denitrification filter, which can effectively save drug costs and operating energy consumption, and realize green, low-carbon and high-quality operation of the sewage plant, has become a technical problem to be solved by those skilled in the art. SUMMARY

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

[0005] To achieve the above purpose, the present application adopts the following technical solutions:

[0006] An RBS intelligent control method for carbon source and phosphorus removal agent dosing of a denitrification filter, comprising: carbon source dosing and phosphorus removal agent dosing.

[0007] The carbon source dosing comprises the following steps:

[0008] The control system collects the influent flow signal, the influent nitrate nitrogen concentration signal, the effluent COD instrument information and the filter DO instrument information, calculates the theoretical carbon source dosing amount through the fuzzy control theory, and then adjusts the actual carbon source dosing amount periodically through the feedback of the effluent nitro nitrogen concentration signal.

[0009] Ensure that the effluent NO X When N<1 mg / L and the carbon source dosing is not excessive, the effluent BOD and COD are less than the influent, and the effluent TN meets the standard under the condition of the minimum carbon source dosing amount, NO2-N accumulation is not produced, and the carbon source dosing is not excessive.

[0010] The control mode of the phosphorus removal agent dosing has the following three modes:

[0011] The phosphorus removal agent dosing preselects a "quantitative" operation mode: in the "quantitative" mode, the dosing amount of the phosphorus removal agent and the flow signal are adjusted to adjust the current dosing amount to the PAC dosing fixed dosing amount set value.

[0012] The phosphorus removal agent is added in the preselected "flow ratio" mode: in the "flow ratio" mode, the phosphorus removal agent and the flow signal are adjusted to adjust the current dosage to the calculated dosage value;

[0013] And the phosphorus removal agent is added in the preselected "RBS" mode: in the "RBS" mode, the PAC dosage is related to the influent flow, the measured value of the effluent pH, the measured value of the influent phosphate, the measured value of the effluent phosphate and the measured value of the effluent SS.

[0014] In actual application, the control mode of the carbon source addition has the following three modes:

[0015] The carbon source addition is preselected in the "quantitative" mode;

[0016] The carbon source addition is preselected in the "flow ratio" mode;

[0017] The carbon source addition is preselected in the "RBS" mode.

[0018] The carbon source addition is preselected in the "quantitative" mode:

[0019] In the "quantitative" mode, the denitrification filter carbon source dosage and the flow signal are adjusted to adjust the current dosage to the set value of the fixed dosage of the denitrification filter carbon source.

[0020] Specifically, the carbon source addition is preselected in the "flow ratio" mode:

[0021] In the "flow ratio" mode, the denitrification filter carbon source dosage and the flow signal are adjusted to adjust the current dosage to the calculated dosage value; the dosage Q 反硝化滤池碳源 is calculated by the following formula:

[0022]

[0023] Wherein, Q 反硝化滤池碳源 is the dosage, unit [l / h]; Q ratio C / N，设定 is the flow ratio set value, unitless; Q 进水 is the influent flow, unit [m³ / h]; [NO x总 ] 进 is the measured value of the total nitrate nitrogen in the influent, unit mgN / l; [NO x总 ] 出，设定 is the set value of the total nitrate nitrogen in the effluent, unit mgN / l;

[0024] And the flow limit is set between the minimum value of the denitrification carbon source dosage flow and the maximum value of the denitrification carbon source dosage flow.

[0025] Further, the carbon source addition is preselected in the "RBS" mode:

[0026] In the "RBS" mode, the denitrification filter carbon source dosage is related to the influent flow rate, the effluent COD measured value, the influent total nitrate nitrogen measured value, the effluent total nitrate nitrogen measured value, and the effluent total nitrate nitrogen set value; the denitrification carbon source dosage Q 反硝化碳源 is calculated by the following formula:

[0027]

[0028] wherein Q 反硝化碳源,RBS is the dosage, unit [l / h]; the proportion C / N，设定 is the C / N-nutrient ratio set value, unit gCOD / gN; Q 进 is the influent flow rate, unit [m³ / h]; [COD] 出 is the effluent COD measured value, unit mgCOD / l; [NO x总 ] 进 is the denitrification filter influent total nitrate nitrogen measured value, unit mgN / l; [NO x总 ] 出 is the denitrification filter effluent total nitrate nitrogen measured value, unit mgN / l; [NO x总 ] 出，设定 is the denitrification filter effluent total nitrate nitrogen set value, unit mgN / l; [C] 碳源 is the carbon source effective content set value, unit mgC / l; [DO] 反硝化 is the denitrification filter DO measured value, unit mg / l;

[0029] And, the flow rate is limited between the minimum value of the denitrification carbon source dosage flow rate and the maximum value of the denitrification carbon source dosage flow rate.

[0030] Further, in order not to exceed the effluent limit value, the calculated dosage is adjusted by correction coefficient k correction;

[0031] When the [NO x总 ] concentration of the effluent exceeds the denitrification filter carbon source dosage RBS effluent nitrate nitrogen maximum value, the correction coefficient k correction is 1.5;

[0032] When the [NO x总 ] concentration of the effluent is lower than the denitrification filter carbon source dosage RBS effluent nitrate nitrogen set value, the correction coefficient k correction is 1.0;

[0033] The intermediate value is linearly adjusted.

[0034] In actual application, in the preselected "flow rate ratio" operation mode of the phosphorus removal agent dosage, the dosage Q 除磷剂流量 is calculated by the following formula:

[0035]

[0036] wherein Q 除磷剂加药 is the dosage, in [l / h]; Q 除磷剂 is the flow rate ratio set value, in [—]; Q 进水 is the influent flow rate, in [m3 / h]; [PO x总 ] 进 is the influent total phosphorus set value, in mgN / l; [PO x总 ] 出，设 is the effluent total phosphorus set value, in mgN / l;

[0037] and the flow rate is limited between the minimum and maximum PAC dosing flow rates.

[0038] In particular, in the preselected “RBS” mode, the dosage Q

[0039]

[0040] wherein Q 除磷剂, RBS is the dosage, in [l / h]; Q 进 is the influent flow rate, in [m3 / h]; [PO x总 ] 进 is the influent phosphorus set value, in mgP / l; [PO x总 ] 出，设定 is the effluent phosphorus set value, in mgP / l; [PO x总 ] 出 is the effluent phosphorus measured value, in mgP / l; [P BioP ] is the phosphorus bound by BioP biological phosphorus removal, in mgP / l; (M 除磷剂 / M P ) 沉淀 is the stoichiometric ratio of the necessary chemical reaction, in g 沉淀 is the value of β, in [—]; [P

[0041] and the flow rate is limited between the minimum and maximum PAC dosing flow rates.

[0042] Further, in order not to exceed the effluent limit value, the calculated dosage will be adjusted by a correction factor;

[0043] When the [PO x总 ] concentration of the effluent exceeds the maximum total phosphorus value of the phosphorus removal agent dosing RBS, the correction factor KF [P出] is 1.5; when the [POx总 ]concentration is lower than the total phosphorus set value of the RBS effluent, the correction coefficient KF is 1.0; when the concentration is between the total phosphorus set value of the RBS effluent and the total phosphorus OK, the correction coefficient KF is linearly adjusted. [P出]

[0044] When the effluent SS value is higher than the maximum value of the RBS effluent SS, the correction coefficient KF is 1.2; when the effluent SS value is lower than the RBS effluent SS OK, the correction coefficient KF is 1.0; and when the effluent SS value is between the RBS effluent SS OK and the maximum value of the RBS effluent SS, the correction coefficient KF is linearly adjusted. SS SS

[0045] When the effluent pH value is higher than the maximum value of the RBS effluent pH, the correction coefficient KF is 0.8; when the effluent pH value is lower than the RBS effluent pH OK, the correction coefficient KF is 1.0; and when the effluent pH value is between the RBS effluent pH OK and the maximum value of the RBS effluent pH, the correction coefficient KF is linearly adjusted. pH pH

[0046] Compared with the prior art, the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter tank has the following advantages:

[0047] The RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter tank provided by the application can timely adjust the dosing amount through the determination of the nitrate nitrogen concentration of the effluent because the empty bed residence time of the filter tank is short, generally 15-30 min; the carbon source dosing system adopts a combination of feedforward and feedback to control the dosing of the carbon source, thereby effectively avoiding the situations of excessive and insufficient dosing, and making the dosing amount meet the removal requirements of TN; the filter tank can control the dosing amount of the carbon source based on the load amount of the nitrate nitrogen to be removed, that is, the system automatically obtains the inflow of the filter tank, combines the nitrate concentrations of the inflow and outflow of the filter tank, and through the calculation of the built-in software of the carbon source dosing field control cabinet, issues an instruction to control the carbon source dosing amount of the dosing pump; the carbon source dosing control system accurately controls the carbon source dosing amount through the feedback of the signals of the nitrate concentration meter and the inflow, and ensures the minimum methanol dosing amount, thereby effectively reducing the operating cost.

[0048] In other words, in the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter tank provided by the application, the carbon source is accurately dosed through the carbon source feedback dosing mechanism of the denitrification deep bed filter tank, and the increase of the COD of the filter tank effluent caused by excessive dosing of the carbon source is avoided; that is, the accurate dosing of the carbon source is realized through conversion, which ensures the denitrification effect of the filter tank and avoids the risk of the increase of the organic matter of the effluent caused by excessive dosing of the carbon source. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 ​​​​​The RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter provided by the embodiment of the present application is a control principle diagram of carbon source RBS dosing control of the denitrification filter.

[0050] Figure 2 The MIAC schematic diagram in the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter provided by the embodiment of the present application is a self-adaptive control model identification diagram. DETAILED DESCRIPTION

[0051] The system needs accurate and reliable nitrate analysis instruments and correction algorithms to ensure that the carbon source dosing is neither excessive nor insufficient, and just meets the design requirements. If the carbon source dosing is insufficient, the effluent water quality standard requirements cannot be met, and the effluent standard requirement TN<10mg / L cannot be met. If the carbon source dosing is excessive, the operation cost is high, and there is a possibility that the effluent BOD will exceed the standard. Therefore, the carbon source dosing needs to be controlled, and a carbon source dosing system is adopted. When the deep bed filter operates in the denitrification mode, external carbon source needs to be dosed to achieve denitrification, and therefore the amount of carbon source dosing directly affects the operation cost and the effluent water quality.

[0052] In order to facilitate understanding, the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter provided by the embodiment of the present application is described in detail below in combination with the drawings of the specification.

[0053] The embodiment of the present application provides an RBS intelligent control method for carbon source and phosphorus removal agent dosing of a denitrification filter, as shown in Figure 1 and Figure 2 , which comprises carbon source dosing and phosphorus removal agent dosing.

[0054] The carbon source dosing comprises the following steps:

[0055] The control system collects the influent flow signal, the influent nitrate nitrogen concentration signal, the effluent COD instrument information, and the filter DO instrument information, calculates the theoretical carbon source dosing amount through the fuzzy control theory, and then adjusts the actual carbon source dosing amount periodically through the feedback of the effluent nitro nitrogen concentration signal.

[0056] The effluent NO X -N<1mg / L and the carbon source dosing is not excessive, the effluent BOD and COD are less than the influent, and the effluent TN meets the standard under the condition of the minimum carbon source dosing amount, NO2-N accumulation is not generated, and carbon source dosing is not excessive.

[0057] The control mode of the phosphorus removal agent dosing has the following three modes:

[0058] The phosphorus removal agent dosing preselects a "quantitative" operation mode: in the "quantitative" mode, the phosphorus removal agent dosing and the flow signal are adjusted to adjust the current dosing amount to the PAC dosing fixed dosing amount set value.

[0059] The phosphorus removal agent dosing pre-selected "flow ratio" operation mode: in the "flow ratio" mode, the phosphorus removal agent dosing and flow signals are adjusted to adjust the current dosing amount to the dosing amount calculated value;

[0060] And, the phosphorus removal agent dosing pre-selected "RBS" operation mode: in the "RBS" mode, the PAC dosing amount is related to the influent flow, the effluent pH measurement value, the influent phosphate measurement value, the effluent phosphate measurement value and the effluent SS measurement value.

[0061] When the carbon source dosing amount is too high, the carbon source dosing cost is increased and the effluent BOD5 is over-standard, in addition, the excess carbon source dosing also causes the large amount of appearance of the Beggiatoa bacteria, which forms a viscous white substance and adheres to the pool wall, affecting the sense of vision;

[0062] When the carbon source dosing amount is insufficient, there are a lot of NO X -N in the effluent, so that the effluent TN cannot be guaranteed to reach the standard, and the carbon source is wasted, the effluent NO X -N is less than 2 mg / L, and NH3-N is less than 1.5 mg / L, if the effluent organic nitrogen is less than or equal to 1.5 mg / L, the effluent TN can be guaranteed to be less than 5 mg / L.

[0063] In the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter provided by the embodiment of the application, the RBS denitrification intelligent dosing control system can accurately control the effluent NO X -N to be less than 2 mg / L or 1 mg / L or less.

[0064] Compared with the prior art, the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter has the following advantages:

[0065] In the RBS intelligent control method for carbon source and phosphorus removal agent dosing of the denitrification filter provided by the embodiment of the application, because the empty bed residence time of the filter is short, generally 15-30 min, the dosing amount can be adjusted in time through the nitrate nitrogen concentration determined in the effluent; the carbon source dosing system adopts the combination of feedforward and feedback to control the carbon source dosing, thereby effectively avoiding the situations of too high and too low dosing amounts, and making the dosing amount meet the removal requirements of TN; the filter can control the carbon source dosing amount based on the load amount of nitrate nitrogen to be removed, that is, the system automatically obtains the influent flow of the filter, combines the influent and effluent nitrate concentrations of the filter, calculates through the built-in software of the carbon source dosing field control cabinet, and issues instructions to control the carbon source dosing amount of the dosing pump; the carbon source dosing control system accurately controls the carbon source dosing amount through the feedback of the nitrate concentration meter and the influent water amount signal, guarantees the minimum methanol dosing amount, and thereby effectively reduces the operating cost.

[0066] In other words, the RBS intelligent control method for adding carbon source and phosphorus removal agent in denitrification filter provided in this embodiment of the invention achieves precise addition of carbon source through the carbon source feedback addition mechanism of denitrification deep bed filter, avoiding the increase of COD in filter effluent due to excessive addition of carbon source; that is, precise carbon source addition is achieved through conversion, ensuring the denitrification effect of filter while avoiding the risk of increased organic matter in effluent caused by excessive addition of carbon source.

[0067] In practical applications, the above-mentioned carbon source addition control modes are as follows:

[0068] Carbon source addition pre-selected "quantitative" operation mode;

[0069] Carbon source addition pre-selected "flow ratio" operation mode;

[0070] Carbon source addition pre-selected "RBS" operation mode.

[0071] Among them, the above-mentioned carbon source addition pre-selected "quantitative" operation mode:

[0072] In "quantitative" mode, the dosing and flow signals of the carbon source in the denitrification filter will be adjusted to bring the current dosing amount to the set value of the fixed dosing amount of the carbon source in the denitrification filter.

[0073] Specifically, the above-mentioned carbon source addition pre-selected "flow ratio" operation mode:

[0074] In "flow ratio" mode, the carbon source dosing and flow signal of the denitrification filter will be adjusted to bring the current dosing rate to the calculated dosing rate; dosing rate Q 反硝化滤池碳源

[0075] It is calculated using the following formula:

[0076]

[0077] Among them, Q 反硝化滤池碳源 Dosage, unit [l / h]; Q ratio C / N，设定 Q is the set value for the flow ratio; it has no unit. 进水 The influent flow rate is expressed in m³ / h; [NO x总 ] 进 Total nitrate nitrogen in influent, measured in mgN / L; [NO x总 ] 出，设定 The set value for total nitrate nitrogen in the effluent, in mgN / l;

[0078] Furthermore, the flow rate is set to be between the minimum and maximum values ​​of the denitrification carbon source dosing flow rate.

[0079] Preferably, the influent flow rate is the total influent flow rate of the plant or the total influent flow rate of the denitrification filter. In order to prevent the unstable operation of the reflux pump due to the fluctuation of the measured value of the influent flow rate, the one-hour average value of the influent flow rate is used for calculation. When the influent nitrate nitrogen measurement device fails to provide a warning, the effluent flow rate is used to calculate the set value. When the measured value of the influent nitrate nitrogen is less than or equal to the set value of the effluent nitrate nitrogen,

[0080] When the effluent COD measurement value provides a warning and the effluent total nitrogen value does not provide a warning, the denitrification carbon source dosage is taken as 0, and the normal dosage is restored when the effluent COD warning is removed. When the effluent COD measurement value provides a warning and the effluent total nitrogen measurement value also provides a warning, the denitrification carbon source dosage is added according to the minimum value, and a pop-up window is used to remind the operation and maintenance technical personnel.

[0081] Further, the above-mentioned carbon source addition pre-selects the "RBS" operation mode:

[0082] In the "RBS" mode, the denitrification filter carbon source dosage is related to the influent flow rate, the measured value of the effluent COD, the measured value of the total influent nitrate nitrogen, the measured value of the total effluent nitrate nitrogen, and the set value of the total effluent nitrate nitrogen. The denitrification carbon source dosage Q 反硝化碳源 is calculated by the following formula:

[0083]

[0084] wherein Q 反硝化碳源,RBS is the dosage, unit [l / h]; the proportion C / N，设定 is the set value of the C / N-nutrient ratio, unit gCOD / gN; Q 进 is the influent flow rate, unit [m³ / h]; [COD] 出 is the measured value of the effluent COD, unit mgCOD / l; [NO x总 ] 进 is the total influent nitrate nitrogen measurement value of the denitrification filter, unit mgN / l; [NO x总 ] 出 is the total effluent nitrate nitrogen measurement value of the denitrification filter, unit mgN / l; [NO x总 ] 出，设定 is the set value of the total effluent nitrate nitrogen of the denitrification filter, unit mgN / l; [C] 碳源 is the set value of the effective content of the carbon source, unit mgC / l; [DO] 反硝化 is the measured value of the DO of the denitrification filter, unit mg / l;

[0085] And the flow rate is limited between the minimum value of the denitrification carbon source dosage flow rate and the maximum value of the denitrification carbon source dosage flow rate.

[0086] The first part of the formula considers the influence of the total nitrate nitrogen measurement of the denitrification filter inlet water on the carbon source dosage; the second part of the formula considers the influence of the total nitrate nitrogen measurement of the denitrification filter outlet water on the carbon source dosage; the third part of the formula considers the influence of the dissolved oxygen of the denitrification filter on the carbon source consumption; and the fourth part of the formula considers the influence of the COD of the denitrification filter outlet water on the carbon source dosage. The following situations may occur during actual operation: the outlet water total nitrate nitrogen concentration is low, and the inlet water COD concentration is high, or the outlet water total nitrate nitrogen concentration is high, and the inlet water COD concentration is low. Through calculation of the relevant parameters of the inlet water or outlet water of the sewage treatment plant, if one side needs to increase the carbon source dosage and the other side only needs to add a small amount, in order to ensure that the feedforward and feedback can effectively add the carbon source, only positive values of each part of the formula can be added, and the calculation results of each part of the formula are realized by MAX {0 | XY} to be positive. Proportion C / N，设定 During debugging, the denitrifying bacteria activity is adjusted.

[0087] Further, in order to not exceed the outlet water limit value, the calculated dosage is adjusted by correction coefficient k correction;

[0088] When the [NO x总 ] concentration of the outlet water exceeds the maximum value of the denitrification filter carbon source dosage RBS outlet water nitrate nitrogen, the correction coefficient k correction is 1.5;

[0089] When the [NO x总 ] concentration of the outlet water is lower than the set value of the denitrification filter carbon source dosage RBS outlet water nitrate nitrogen, the correction coefficient k correction is 1.0;

[0090] The correction coefficient is linearly adjusted between the values.

[0091] In actual application, in the above phosphorus removal agent addition pre-selected "flow ratio" operation mode, the dosage Q 除磷剂流量 is calculated by the following formula:

[0092]

[0093] Wherein, Q 除磷剂加药 is the dosage, unit [l / h]; Q 除磷剂 is the flow ratio set value, unitless; Q 进水 is the inlet water flow, unit [m³ / h]; [PO x总 ] 进 is the inlet water total phosphorus measurement, unit mgN / l; [PO x总 ] 出，设 is the outlet water total phosphorus set value, unit mgN / l;

[0094] And, the flow rate is set to be limited between the minimum value and the maximum value of the PAC dosing flow rate.

[0095] Preferably, the influent flow rate is measured at the influent. In order to prevent the dosing pump from operating unstably due to fluctuations in the measured value of the influent flow rate, the 1-hour average of the influent flow rate is used for the calculation. When a malfunction warning occurs in the influent phosphate measuring device, the effluent flow rate is used in the formula to calculate the set value. When the influent phosphate measured value is less than or equal to the effluent phosphate set value, One is taken as 0.

[0096] Specifically, in the preselected "RBS" operating mode of the above-mentioned phosphorus removal agent dosing, the dosing amount Q of the phosphorus removal agent is calculated by the following formula:

[0097]

[0098] wherein Q 除磷剂, RBS is the dosing amount, in units of [l / h]; Q 进 is the influent flow rate, in units of [m³ / h]; [PO x总 ] 进 is the influent phosphate measured value, in units of mgP / l; [PO x总 ] 出，设定 is the effluent phosphate set value, in units of mgP / l; [PO x总 ] 出 is the effluent phosphate measured value, in units of mgP / l; [P BioP ] is the phosphorus bound by the BioP biological phosphorus removal, in units of mgP / l; (M 除磷剂 / M P ) 沉淀 is the stoichiometric ratio of the necessary chemical reaction, in units of g phosphorus removal agent / g P; β 沉淀 is the β value, without units; [phosphorus removal agent] is the effective content set value of the phosphorus removal agent, in units of %;

[0099] And, the flow rate is set to be limited between the minimum value and the maximum value of the phosphorus removal agent dosing flow rate.

[0100] Further, in order not to exceed the effluent limit value, the calculated dosing amount will be adjusted by a correction factor;

[0101] When the [PO x总 ] concentration of the effluent exceeds the maximum value of the total phosphorus of the phosphorus removal agent dosing RBS, the correction factor KF [P出] is 1.5; when the [PO x总 ] concentration of the effluent is lower than the set value of the total phosphorus of the phosphorus removal agent dosing RBS, the correction factor KF [P出] is 1.0; and between the values, the correction factor is adjusted linearly;

[0102] When the effluent SS value is higher than the maximum effluent SS value of the phosphorus removal agent dosing RBS, 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 dosing RBS, the correction coefficient KF SS is 1.0; for the intermediate value, the correction coefficient is linearly adjusted;

[0103] When the effluent pH value is higher than the maximum effluent pH value of the phosphorus removal agent dosing RBS, the correction coefficient KF pH is 0.8; when the effluent pH value is lower than the effluent pH OK of the phosphorus removal agent dosing RBS, the correction coefficient KF pH is 1.0; for the intermediate value, the correction coefficient is linearly adjusted.

[0104] It needs to be supplemented here that the principle of denitrification: denitrification reaction is a biochemical process completed by a group of heterotrophic microorganisms, which is the reaction of reducing nitrite and nitrate to nitrogen, nitric oxide or oxidized nitrogen under the condition of lack of oxygen (no molecular state dissolved oxygen). The microorganisms involved in the denitrification process are denitrifying bacteria; denitrifying bacteria are facultative bacteria and almost ubiquitous in natural environment, and many common microorganisms in wastewater treatment system are denitrifying bacteria, such as Proteus, Micrococcus, Pseudomonas, Bacillus, Alcaligenes and Flavobacterium, most of which are facultative bacteria. When there is dissolved oxygen, denitrifying bacteria decompose organic matter and use molecular oxygen as the final electron acceptor; in the absence of dissolved oxygen, denitrifying bacteria use N 5+ and N 3+ in nitrate and nitrite as electron acceptors in energy metabolism, O 2- as hydrogen acceptor to generate H2O and OH - alkalinity, organic matter as carbon source and electron donor to provide energy and be oxidized and stabilized. Among them, the biological denitrification process can be represented by the following two formulas: 2NO2 - +6H (electron donor organic matter) → N2 +2H2O +2OH - and 2NO3 - +9H (electron donor organic matter) → N2 +3H2O +3OH - ;

[0105] The conversion of nitrite and nitrate in the denitrification process is completed by the assimilation and dissimilation of denitrifying bacteria; the assimilation refers to the process that nitrite and nitrate are reduced into ammonia nitrogen to synthesize new microbial cells and nitrogen becomes the component of cytoplasm; the dissimilation refers to the process that nitrite and nitrate are reduced into gaseous substances such as nitrogen, nitric oxide or nitrous oxide, wherein the main component is nitrogen, and the nitrogen removed by dissimilation accounts for about 70-75% of the total removal amount.

[0106] It also needs to be supplemented here that the carbon source dosing point of the sewage plant is mainly concentrated in the anoxic zone of the biochemical pool and the water inlet end of the deep bed denitrification filter. The way of dosing in the anoxic zone of the biochemical pool is described in detail in the invention patent “RBS intelligent control method for sewage plant, CN114920358B”; this application mainly introduces the intelligent and precise control of carbon source dosing at the water inlet end of the deep bed denitrification filter.

[0107] In sewage treatment, the denitrification filter is usually used as a unit for advanced treatment of sewage and is placed at the end of the entire sewage treatment process. In the case that the carbon source in the sewage itself is not very sufficient, the carbon source will be consumed by the preceding process units, such as the biochemical pool, and there is usually limited carbon source or difficult-to-biodegrade carbon source left in the denitrification filter stage. Without dosing carbon source, it is difficult to ensure the effect of denitrification, and if too much carbon source is dosed, the COD in the effluent will not decrease but increase, affecting the effluent quality, so the precise dosing of carbon source in the denitrification filter is also very important.

[0108] In addition, by reacting the coagulant with the phosphate in the sewage, insoluble phosphorus-containing compounds and flocculation bodies are generated, which can separate the phosphorus in the sewage and achieve the purpose of phosphorus removal. The commonly used coagulants for chemical phosphorus removal include aluminum salts and iron salts. When using the filter for filtration, the micro-flocculation direct filtration mode of the denitrification filter is used to complete the flocculation and SS interception process by using the unique turbulence effect of the filter, which can further remove the phosphate. If the phosphorus removal agent is excessively dosed in the denitrification filter, it will increase the filtration resistance of the filter and cause frequent backwashing of the filter, and if the phosphorus removal agent is insufficiently dosed, it may cause the effluent phosphate to exceed the standard, so the dosing of the phosphorus removal agent in the denitrification filter also needs to be intelligently and precisely controlled.

[0109] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A smart control method for the addition of carbon source and phosphorus removal agent in a denitrification filter (RBS), characterized in that, include: Carbon source addition and phosphorus removal agent addition; The carbon source addition includes the following steps: the control system collects influent flow rate signals, influent nitrate nitrogen concentration signals, effluent COD meter information, and filter DO meter information; calculates the theoretical carbon source addition amount using fuzzy control theory; and then periodically adjusts the actual carbon source addition amount based on feedback from the effluent nitrate nitrogen concentration signal; ensuring that the effluent NO... X -N < 1 mg / L and carbon source addition is not excessive, effluent BOD and COD are lower than influent, and effluent TN meets the standard under the condition of minimum carbon source addition, without NO2-N accumulation or excessive carbon source addition. The control modes for phosphorus removal agent dosing include the following three: Pre-selected "Quantitative" operation mode: In "Quantitative" mode, the phosphorus removal agent dosing and flow signals are adjusted to bring the current dosage to the fixed PAC dosage setting; Pre-selected "Flow Ratio" operation mode: In "Flow Ratio" mode, the phosphorus removal agent dosing and flow signals are adjusted to bring the current dosage to the calculated dosage value; and Pre-selected "RBS" operation mode: In "RBS" mode, the PAC dosage is related to the influent flow rate, effluent pH measurement, influent phosphate measurement, effluent phosphate measurement, and effluent SS measurement. The carbon source addition control modes include the following three: pre-selected "quantitative" operation mode; pre-selected "flow ratio" operation mode; and pre-selected "RBS" operation mode. The pre-selected "RBS" operation mode is as follows: In "RBS" mode, the carbon source dosage for the denitrification filter is related to the influent flow rate, effluent COD measurement, influent total nitrate nitrogen measurement, effluent total nitrate nitrogen measurement, and effluent total nitrate nitrogen setpoint; the denitrification carbon source dosage Q 反硝化碳源 It is calculated using the following formula: Among them, Q 反硝化碳源,RBS Dosage, unit [l / h]; proportion C / N，设定 C / N ratio setpoint, unit: gCOD / gN; Q 进 Influent flow rate, unit [m³ / h]; [COD] 出 The measured COD value of the effluent is in mgCOD / L; [NO x总 ] 进 The total nitrate nitrogen content in the influent to the denitrification filter is measured in mgN / L; [NO x总 ] 出 The total nitrate nitrogen content in the effluent from the denitrification filter is measured in mgN / L; [NO x总 ] 出，设定 The total nitrate nitrogen setpoint for the effluent from the denitrification filter, in mgN / l; [C] 碳源 Set the effective carbon source content as a value, in mg C / L; [DO] 反硝化 The measured DO value in the denitrification filter is expressed in mg / L. Furthermore, the flow rate is set to be between the minimum and maximum values ​​of the denitrification carbon source dosing flow rate.

2. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 1, characterized in that, The carbon source addition pre-selected "quantitative" operation mode: In "quantitative" mode, the dosing and flow signals of the carbon source in the denitrification filter will be adjusted to bring the current dosing amount to the set value of the fixed dosing amount of the carbon source in the denitrification filter.

3. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 1, characterized in that, The carbon source addition pre-selected "flow ratio" operation mode: In "flow ratio" mode, the carbon source dosing and flow signal of the denitrification filter will be adjusted to bring the current dosing rate to the calculated dosing rate; dosing rate Q 反硝化滤池碳源 It is calculated using the following formula: Among them, Q 反硝化滤池碳源 Dosage, unit [l / h]; Q ratio C / N，设定 Q is the set value for the flow ratio; it has no unit. 进水 The influent flow rate is expressed in m³ / h; [NO x总 ] 进 Total nitrate nitrogen in influent, measured in mgN / L; [NO x总 ] 出，设定 The set value for total nitrate nitrogen in the effluent, in mgN / l; Furthermore, the flow rate is set to be between the minimum and maximum values ​​of the denitrification carbon source dosing flow rate.

4. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 1, characterized in that, In order to avoid exceeding the effluent limit, the calculated dosage will be adjusted by using a correction factor k. When the water comes out [NO x总 If the concentration exceeds the maximum nitrate nitrogen value in the effluent of the denitrification filter carbon source dosing RBS, then the correction factor k is corrected to 1.5; When the water comes out [NO x总 If the concentration is lower than the set value of nitrate nitrogen in the effluent of the denitrification filter carbon source dosing RBS, then the correction factor k is corrected to 1.0; The intermediate values ​​are adjusted linearly by the correction coefficient.

5. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 1, characterized in that, In the pre-selected "flow ratio" operation mode for phosphorus removal agent dosing, the dosage Q is... 除磷剂流量 It is calculated using the following formula: Among them, Q 除磷剂加药 Dosage, unit [l / h]; Q ratio 除磷剂 Q is the set value for the flow ratio; it has no unit. 进水 The influent flow rate is expressed in m³ / h; [PO₄] x总 ] 进 The total phosphate content in the influent is measured in mgN / L; [PO4] x总 ] 出，设 The set value for total phosphate in the effluent, in mgN / l; Furthermore, the flow rate is set to be between the minimum and maximum PAC dosing flow rates.

6. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 1, characterized in that, In the pre-selected "RBS" operation mode for phosphorus removal agent addition, the dosage Q of phosphorus removal agent is calculated using the following formula: Among them, Q 除磷剂, RBS This refers to the dosage, expressed in [l / h]; Q 进 The influent flow rate is expressed in m³ / h; [PO₄] x总 ] 进 The measured value of phosphate in the influent is in mgP / L; [PO4] x总 ] 出，设定 The setpoint for effluent phosphate, in mgP / L; [PO4] x总 ] 出 The measured phosphate content in the effluent is in mgP / L; [P BioP [This refers to phosphorus bound by BioP biological phosphorus removal, expressed in mgP / L; (M 除磷剂 / M P ) 沉淀 For the necessary stoichiometric ratio of the chemical reaction, the unit is g phosphorus removal agent / gP; β 沉淀 This is the β value, unitless; [Phosphorus removal agent] is the set value of the effective content of the phosphorus removal agent, in % %. Furthermore, the flow rate is set to be between the minimum and maximum values ​​of the phosphorus removal agent dosing flow rate.

7. The intelligent control method for adding carbon source and phosphorus removal agent to the denitrification filter (RBS) according to claim 6, characterized in that, In order to avoid exceeding the effluent limit, the calculated dosage will be adjusted using a correction factor; When the water flows out [PO] x总 If the concentration exceeds the maximum total phosphorus value in the effluent of RBS after phosphorus removal agent addition, then the correction factor KF [P出] It is 1.5; when the effluent [PO] x总 If the concentration is lower than the set value of total phosphorus in the effluent of RBS after phosphorus removal agent addition, then the correction factor KF [P出] The value is 1.0; the intermediate values ​​are adjusted linearly by the correction factor. When the effluent SS value is higher than the maximum SS value of the effluent after adding phosphorus removal agent RBS, the correction factor KF SS The correction factor is 1.2; when the effluent SS value is lower than the SSOK value of the effluent after adding phosphorus removal agent RBS, the correction factor KF is 1.

2. SS The value is 1.0; the intermediate values ​​are adjusted linearly by the correction factor. When the pH value of the effluent is higher than the maximum pH value of the effluent after adding phosphorus removal agent RBS, the correction factor KF pH The correction factor is 0.8; when the effluent pH is lower than the pH of the RBS effluent after phosphorus removal agent addition, the correction factor KF is [value missing]. pH The value is 1.0; the intermediate values ​​are adjusted linearly by the correction factor.

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