A method and apparatus for in-situ precision chemical phosphorus removal

Abstract

This invention relates to the field of wastewater phosphorus removal technology, specifically disclosing a control method and apparatus for in-situ precision chemical phosphorus removal, comprising: an online monitoring system, an intelligent analysis system, a precision control system, and an anomaly alarm system. The online monitoring system of this invention can sample and detect wastewater in real time. Through the intelligent analysis system, based on empirical formulas, it calculates the precise phosphorus removal agent dosage ratio and flow rate, and controls precise dosing. Based on years of production and operation experience, it sets multiple warning values; when different levels are reached, it promptly issues audible and central control interface alarms, and simultaneously activates automatic sampling. The control method of this invention achieves real-time intelligent analysis and indicator prediction of chemical phosphorus removal effects, significantly improving the precision and accuracy of chemical phosphorus removal, maximizing the conservation of phosphorus removal agents, and effectively enhancing environmental risk prevention capabilities.

Description

Technical Field

[0001] This invention belongs to the field of wastewater phosphorus removal technology, specifically relating to an in-situ precision chemical phosphorus removal control method and apparatus. Background Technology

[0002] With increasing human activities in exploiting natural resources, large amounts of phosphorus-containing domestic sewage and industrial wastewater are discharged into the environment, increasing the nutrient load on aquatic bodies and directly resulting in eutrophication. Eutrophication affects the photosynthesis of aquatic plants, may cause supersaturation of dissolved oxygen, and leads to the decomposition of organic matter in the water under anaerobic conditions, producing harmful gases and causing mass fish deaths. In addition, eutrophic water contains nitrates and nitrites, and long-term consumption of water with these substances exceeding certain standards can cause poisoning and illness in humans and animals.

[0003] Phosphorus-containing substances in wastewater can be removed by both chemical and biological methods. However, since biological phosphorus removal processes often cannot guarantee that the total phosphorus in the effluent will consistently meet the standard requirement of 0.5 mg / L, it is often necessary to add phosphorus removal agents to the water to assist in phosphorus removal through chemical methods.

[0004] Chinese patent CN 103964647 A discloses a three-stage biological filter system for denitrification and phosphorus removal from industrial waste and its wastewater treatment method, belonging to the field of wastewater denitrification and phosphorus removal. The system includes a storage tank, a primary device, a secondary device, and a tertiary device. The storage tank is located above the primary device. The primary device is positioned above the secondary device, with its bottom connected to the bottom of the secondary device via a pipe equipped with a bottom solenoid valve. A bottom outlet solenoid valve is also installed on the pipe connecting the bottom outlet of the primary device to the top of the secondary device. The secondary device is positioned above the tertiary device, with its bottom connected to the bottom of the tertiary device via a pipe equipped with a bottom solenoid valve. A bottom outlet solenoid valve is also installed on the pipe connecting the bottom outlet of the secondary device to the top of the tertiary device. This system fully utilizes the synergistic effect of filter media, has a small footprint and low operating costs, and is highly efficient in removing nitrogen and phosphorus from wastewater. Although the above scheme has many beneficial effects, it usually requires the addition of some chemical reagents when removing nitrogen and phosphorus from water samples. After the reaction in a three-stage device, the samples are monitored. However, the monitoring of the indicators is usually delayed by 2-3 hours, making it impossible to monitor phosphorus concentration in real time. This poses a high environmental risk, and it is also easy to add too much chemical reagent, resulting in waste and poor environmental performance.

[0005] In response, the inventors proposed a rapid sampling device based on membrane filtration technology and a method for achieving precise phosphorus removal to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a method and apparatus for controlling in-situ precise chemical phosphorus removal, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for controlling in-situ precision chemical phosphorus removal includes:

[0009] An online monitoring system is provided, which uses online equipment to monitor the total phosphorus index of the influent in the mixing zone and the effluent in the flocculation zone in real time. The online monitoring system specifically includes a sampling system, a sample supply system, and a sampling system.

[0010] The intelligent analysis system simulates the actual empirical formulas for the dosage ratio of phosphorus removal agents and the total phosphorus removal effect based on the monitoring results of the most recent 24 hours.

[0011] The precision control system forms a data pair (x1, y1, z1) based on the current monitoring results and the target or warning values ​​of the indicators. x1: total phosphorus value of mixed influent, y1: total phosphorus value of flocculated effluent, z1: ​​total phosphorus target or warning value. Based on the empirical formula of the intelligent analysis system, it calculates the precise phosphorus removal agent dosage ratio and dosage flow rate, and controls the precise dosage.

[0012] Based on years of production and operation experience, the abnormal alarm system sets multi-level early warning values ​​for x1 and y1. When different levels are reached, it promptly issues alarms via sound control and the central control interface, and simultaneously activates automatic sampling.

[0013] Preferably, the empirical formula is:

[0014] ;

[0015] Where a is the coefficient of x1 and b is the coefficient of z1.

[0016] Preferably, the total phosphorus value x1 of the mixed influent and the total phosphorus target value or warning value z1 are used as input features, and the total phosphorus value y1 of the flocculated effluent is used as the output label;

[0017] Construct a feature matrix by merging the input features x1 and z1 into a single feature matrix X;

[0018] Initialize the linear regression model and use it to build the model;

[0019] Model training involves using the model's fit method to train the feature matrix X and output label y1, thereby obtaining the optimal coefficients a and b.

[0020] Preferably, coefficients a and b are obtained by training a linear regression model that minimizes the loss function. In linear regression, the loss function is the squared loss, which is the sum of squares of the differences between the actual output and the model's predicted output. Minimizing the squared loss can be obtained by solving the least squares method, as follows:

[0021] Suppose we have N data points (x1i, z1i, y1i), where i represents the i-th data point. The expression for the linear regression model is:

[0022] ;

[0023] Where ϵi is the error term of the model;

[0024] To determine the coefficients a and b that minimize the squared loss:

[0025] ;

[0026] By taking the partial derivatives of J(a,b) with respect to a and b respectively, and then setting the partial derivatives to zero, we can obtain the system of equations for the least squares method. Solving this system of equations will give us the optimal coefficients a and b.

[0027] Preferably, the sampling system comprises a submersible pump unit, an inlet pipe unit, a housing unit, an outlet pipe unit, an overflow pipe unit, a flushing water pipe unit, and a venting pipe unit.

[0028] Preferably, the sample supply system comprises a membrane module unit, a peristaltic pump unit, a sample supply tube unit, and a sample retention bottle unit.

[0029] Preferably, the sampling system comprises a sampling pump unit and a sample supply tube unit.

[0030] Preferably, the membrane assembly comprises a frame unit, a filter membrane unit, and an inner liner unit.

[0031] A control device for in-situ precision chemical phosphorus removal includes the control method for in-situ precision chemical phosphorus removal described above, wherein the control device is used to achieve in-situ precision chemical phosphorus removal.

[0032] Compared with the prior art, the beneficial effects of the present invention are:

[0033] (1) The present invention uses a submersible pump to transport the flocculated mixed liquid sample from the flocculation stirring zone of the sedimentation tank to the box unit. The mixed liquid containing flocs is evenly distributed to both sides of the membrane module. The flocs in the mixed liquid are trapped on the membrane surface and carried away by the mixed liquid. The water in the mixed liquid can pass through the membrane smoothly without the need for the slow sedimentation process in the process to separate the flocs and water, thus realizing the rapid simulation of the three-stage treatment situation of membrane filtration.

[0034] (2) The online monitoring system of the present invention can sample and detect wastewater in real time. Through the intelligent analysis system, it calculates the precise dosage ratio and flow rate of phosphorus removal agent according to empirical formulas and controls the precise dosage. Based on years of production and operation experience, it sets multi-level early warning values. When different levels are reached, it promptly issues sound control and central control interface alarms and starts automatic sampling. The control method of the present invention realizes real-time intelligent analysis and index prediction of chemical phosphorus removal effect, significantly improves the precision and accuracy of chemical phosphorus removal, saves phosphorus removal agent to the maximum extent, and effectively enhances the ability to prevent environmental risks. Attached Figure Description

[0035] Figure 1 This is a block diagram of an online monitoring system for a control method of in-situ precision chemical phosphorus removal according to the present invention;

[0036] Figure 2 This is a schematic diagram of the overall composition of a control device for in-situ precision chemical phosphorus removal according to the present invention;

[0037] Figure 3 This is a top view of the housing unit of the control device for in-situ precision chemical phosphorus removal according to the present invention;

[0038] Figure 4 This is a side view of the housing unit of a control device for in-situ precision chemical phosphorus removal according to the present invention.

[0039] Figure 5 This is a schematic diagram of an in-situ precision chemical phosphorus removal control method and apparatus according to the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0041] Example 1:

[0042] Please see Figures 1 to 5 As shown, an in-situ precision chemical phosphorus removal control method includes:

[0043] An online monitoring system is provided, which uses online equipment to monitor the total phosphorus index of the influent in the mixing zone and the effluent in the flocculation zone in real time. The online monitoring system specifically includes a sampling system, a sample supply system, and a sampling system.

[0044] The intelligent analysis system simulates the actual empirical formulas for the dosage ratio of phosphorus removal agents and the total phosphorus removal effect based on the monitoring results of the most recent 24 hours (one pair every 30 minutes, 48 ​​data pairs);

[0045] The precision control system forms a data pair (x1, y1, z1) based on the current monitoring results and the target or warning values ​​of the indicators. x1: total phosphorus value of mixed influent, y1: total phosphorus value of flocculated effluent, z1: ​​total phosphorus target or warning value. Based on the empirical formula of the intelligent analysis system, it calculates the precise phosphorus removal agent dosage ratio and dosage flow rate, and controls the precise dosage.

[0046] Based on years of production and operation experience, the abnormal alarm system sets multi-level early warning values ​​for x1 and y1. When different levels are reached, it promptly issues alarms via sound control and the central control interface, and simultaneously activates automatic sampling.

[0047] The empirical formula is:

[0048] ;

[0049] Where a is the coefficient of x1 and b is the coefficient of z1.

[0050] Specifically, the total phosphorus value x1 of the mixed influent and the total phosphorus target or warning value z1 are used as input features, and the total phosphorus value y1 of the flocculated effluent is used as the output label.

[0051] Construct a feature matrix by merging the input features x1 and z1 into a single feature matrix X;

[0052] Initialize the linear regression model and use it to build the model;

[0053] Model training involves using the model's fit method to train the feature matrix X and output label y1, thereby obtaining the optimal coefficients a and b.

[0054] Specifically, coefficients a and b are obtained by training a linear regression model that minimizes the loss function. In linear regression, the loss function is the squared loss, which is the sum of squares of the differences between the actual output and the model's predicted output. Minimizing the squared loss can be achieved by solving the least squares method, as follows:

[0055] Suppose we have N data points (x1i, z1i, y1i), where i represents the i-th data point. The expression for the linear regression model is:

[0056] ;

[0057] Where ϵi is the error term of the model;

[0058] To determine the coefficients a and b that minimize the squared loss:

[0059] ;

[0060] By taking the partial derivatives of J(a,b) with respect to a and b respectively, and then setting the partial derivatives to zero, we can obtain the system of equations for the least squares method. Solving this system of equations will give us the optimal coefficients a and b.

[0061] As can be seen from the above, the online monitoring system can sample and test wastewater in real time. Through the intelligent analysis system, it can calculate the precise dosage ratio and flow rate of phosphorus removal agent based on empirical formulas and control the precise dosage. Based on years of production and operation experience, it can set multiple warning values. When different levels are reached, it can promptly issue audible and central control interface alarms and start automatic sampling.

[0062] The control method of this invention enables real-time intelligent analysis and index prediction of chemical phosphorus removal effect, significantly improving the precision and accuracy of chemical phosphorus removal, maximizing the conservation of phosphorus removal agents, and effectively enhancing the ability to prevent environmental risks.

[0063] Example 2:

[0064] A control device for in-situ precision chemical phosphorus removal includes the control method described above, wherein the control device includes a sampling system, a sample supply system, and a sampling system.

[0065] Specifically, the sampling system comprises a submersible pump unit, an inlet pipe unit, a housing unit, an outlet pipe unit, an overflow pipe unit, a flushing water pipe unit, and a venting pipe unit. The submersible pump unit and the inlet pipe unit are connected in sequence on one side of the housing unit. The inlet pipe unit is connected to the flocculation and mixing zone of the sedimentation tank. The submersible pump unit pumps sewage from the flocculation and mixing zone of the sedimentation tank into the housing unit.

[0066] The side of the inlet pipe unit is connected to a flushing water pipe unit for flushing the inlet pipe. Two vent pipe units are set at the bottom of the tank unit for draining the remaining sewage at the bottom of the tank. On the side of the tank unit away from the inlet pipe unit, from bottom to top, there are an outlet pipe unit and an overflow pipe unit, which are used to drain the sewage after testing and to prevent sewage from overflowing, respectively.

[0067] Specifically, the sample supply system comprises a membrane module unit, a peristaltic pump unit, a sample supply tube unit, and a sample retention bottle unit. The membrane module unit is located in the middle of the housing unit. The water sample filtered by the membrane is transported to the sample supply tube unit through the peristaltic pump unit. The other end of the sample supply tube unit is connected to an online monitoring device for monitoring the water sample. After monitoring is completed, the water sample with abnormality is discharged to the sample retention bottle unit for collection and storage.

[0068] Specifically, the sampling system comprises a sampling pump unit and a sample supply tube unit. The sampling pump unit is used to extract water samples from the sample supply tube unit and transport them to the online monitoring equipment.

[0069] Specifically, the membrane assembly comprises a frame unit, a filter membrane unit, and an inner liner unit.

[0070] As can be seen from the above, the flocculated mixed liquid sample is transported from the flocculation mixing zone of the sedimentation tank to the box unit by a submersible pump. The mixed liquid containing flocs is evenly distributed to both sides of the membrane module. The flocs in the mixed liquid are trapped on the membrane surface and carried away by the mixed liquid. The water in the mixed liquid can pass through the membrane smoothly without the need for slow sedimentation and other processes to separate the flocs and water. This achieves rapid simulation of tertiary treatment by membrane filtration.

[0071] Water samples filtered through the membrane are transported to online monitoring equipment via a peristaltic pump unit and a sample supply tube. A sampling pump unit then collects samples for testing, enabling real-time prediction of the tertiary treatment effect. Automatic detection equipment extracts water samples from the front end of the tertiary treatment process and monitors the data to obtain real-time total phosphorus water quality indicators. The real-time water quality data from the automatic detection equipment is transmitted to a PLC controller, which determines the range of the real-time water quality data based on the set tiered control limits. Furthermore, an automatic dosing system can be configured as needed. Based on the tiered control limits for total phosphorus and the actual dosage ratio, automatic dosing systems and alarm prompts can be developed for each level, thereby improving the accuracy of effluent indicators, saving on phosphorus removal agent costs, and enhancing environmental risk control capabilities.

[0072] All standard parts used in this invention can be purchased commercially, and irregularly shaped parts can be customized according to the description and drawings. The specific connection methods for each part all employ conventional methods such as bolts, rivets, and welding, which are mature technologies in the prior art. The machinery, parts, and equipment all use conventional models in the prior art, and the circuit connections also use conventional connection methods in the prior art, which will not be detailed here. Any content not described in detail in this specification belongs to the prior art known to those skilled in the art.

[0073] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0074] The accompanying drawings of the embodiments disclosed in this invention only involve structures relevant to the embodiments disclosed in this invention. Other structures can be referred to with common designs. Unless otherwise specified, the same embodiment and different embodiments of this invention can be combined with each other.

[0075] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for controlling in-situ precise chemical phosphorus removal, characterized in that, include: An online monitoring system is provided, which uses online equipment to monitor the total phosphorus index of the influent in the mixing zone and the effluent in the flocculation zone in real time. The online monitoring system specifically includes a sampling system, a sample supply system, and a sampling system. The intelligent analysis system simulates the actual empirical formulas for the dosage ratio of phosphorus removal agents and the total phosphorus removal effect based on the monitoring results of the most recent 24 hours. The precision control system forms a data pair (x1, y1, z1) based on the current monitoring results and the target or warning values ​​of the indicators. x1: total phosphorus value of mixed influent, y1: total phosphorus value of flocculated effluent, z1: ​​total phosphorus target or warning value. Based on the empirical formula of the intelligent analysis system, it calculates the precise phosphorus removal agent dosage ratio and dosage flow rate, and controls the precise dosage. Based on years of production and operation experience, the abnormal alarm system sets multi-level early warning values ​​for x1 and y1. When different levels are reached, it promptly issues sound and central control interface alarms and simultaneously activates automatic sampling. The empirical formula is: ； Where a is the coefficient of x1 and b is the coefficient of z1; Use the total phosphorus value x1 of the mixed influent and the target or warning value z1 of total phosphorus as input features, and the total phosphorus value y1 of the flocculated effluent as the output label; Construct a feature matrix by merging the input features x1 and z1 into a single feature matrix X; Initialize the linear regression model and use it to build the model; Model training involves using the model's fit method to train the feature matrix X and output label y1, thereby obtaining the optimal coefficients a and b. The coefficients a and b are obtained by training a linear regression model that minimizes the loss function. In linear regression, the loss function is the squared loss, which is the sum of the squares of the differences between the actual output and the model's predicted output. Minimizing the squared loss can be obtained by solving the least squares method, as follows: Suppose we have N data points (x1i, z1i, y1i), where i represents the i-th data point. The expression for the linear regression model is: ； Where ϵi is the error term of the model; To determine the coefficients a and b that minimize the squared loss: ； By taking the partial derivatives of J(a,b) with respect to a and b respectively, and then setting the partial derivatives to zero, we can obtain the system of equations for the least squares method. Solving this system of equations will give us the optimal coefficients a and b.

2. The in-situ precision chemical phosphorus removal control method according to claim 1, characterized in that: The sampling system consists of a submersible pump unit, an inlet pipe unit, a housing unit, an outlet pipe unit, an overflow pipe unit, a flushing water pipe unit, and a venting pipe unit.

3. The in-situ precision chemical phosphorus removal control method according to claim 1, characterized in that: The sample supply system consists of a membrane module unit, a peristaltic pump unit, a sample supply tube unit, and a sample retention bottle unit.

4. The in-situ precision chemical phosphorus removal control method according to claim 1, characterized in that: The sampling system consists of a sampling pump unit and a sample supply tube unit.

5. The in-situ precision chemical phosphorus removal control method according to claim 3, characterized in that: The membrane module comprises a frame unit, a filter membrane unit, and an inner liner unit.

6. A control device for in-situ precision chemical phosphorus removal, characterized in that: The invention includes a control method for in-situ precision chemical phosphorus removal as described in any one of claims 1-5, wherein the control device is used to achieve in-situ precision chemical phosphorus removal.

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