Chemical phosphorus removal dosing control method for sewage treatment plant

Abstract

The invention relates to a chemical phosphorus removal dosing control method for a sewage treatment plant, which comprises the following steps: installing a water quality sensor at a key node of the sewage treatment plant, and the sensor is used for monitoring the total phosphorus concentration CTP, the target effluent phosphorus concentration CTPout, the pH value, the temperature, the dissolved oxygen concentration and the organic matter concentration in the sewage in real time; real-time water quality parameters acquired by each sensor are transmitted to a central control system through a data acquisition unit, and are subjected to denoising, filtering and normalization preprocessing, so that the quality and consistency of data are ensured; and the real-time dosage is calculated through the calculation model. According to the chemical phosphorus removal dosing control method for the sewage treatment plant, the optimal phosphorus removal effect is ensured by monitoring water quality parameters in real time and dynamically adjusting the dosing amount, and excessive use or insufficient use of chemicals is avoided; the control strategy can be automatically adjusted according to different water quality conditions, the system is suitable for various types of sewage plants and complex water quality changes, and the adaptability and flexibility of the system are enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of sewage treatment, and in particular relates to a method for controlling chemical phosphorus removal and dosing in a sewage treatment plant. Background Art

[0002] In the chemical phosphorus removal process of sewage treatment plants, metal salts (such as iron salts, aluminum salts) or alkaline substances (such as lime) are usually added to the sewage to make phosphate ions react with metal ions or calcium ions to form insoluble phosphate precipitates, thereby removing phosphorus from the water. The traditional method of calculating the dosage of chemical phosphorus removal mainly relies on empirical values ​​or fixed ratios, and the dosage is usually determined based on the total phosphorus concentration in the influent and the required phosphorus concentration in the effluent. This method has the following problems: Impact of water quality fluctuations: The phosphorus content and other water quality parameters in sewage (such as pH, dissolved oxygen, organic matter concentration, etc.) will change with time and season. A fixed dosing ratio cannot adapt to these fluctuations and may result in excessive or insufficient dosage.

[0003] Differences in reaction conditions: Different sewage treatment processes (such as biological treatment, chemical precipitation, etc.) have a significant impact on the effect of chemical phosphorus removal. The fixed proportion of dosage cannot take these differences into account, resulting in unstable treatment effects.

[0004] Low utilization rate of reagents: Traditional methods of adding reagents often lead to waste of reagents, increase operating costs, and may cause secondary pollution to the environment. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a new dosing method based on real-time water quality parameters. This method combines real-time water quality parameters and reaction kinetics models, and can dynamically adjust the dosage to ensure optimal phosphorus removal effect while minimizing the waste of agents.

[0006] The technical objectives of the present invention are achieved through the following technical solutions: A method for controlling dosing of chemical phosphorus removal in a sewage treatment plant, comprising: S1 installs water quality sensors at key nodes of the sewage plant. The sensors are used to monitor the total phosphorus concentration CTP in the sewage and the target effluent phosphorus concentration CTP in real time. out , pH value, temperature, dissolved oxygen concentration and organic matter concentration; S2 transmits the real-time water quality parameters collected by each sensor to the central control system through the data acquisition unit, and performs denoising, filtering and normalization preprocessing to ensure the quality and consistency of the data; S3 by formula , calculate the dosage Q at the current moment, where: Q is the dosage of the drug to be added; CTP is the total phosphorus concentration in the influent; CTP out is the target effluent phosphorus concentration; CD is the concentration of the active ingredient of the agent; V is the reaction volume; t is the reaction time; K is the reaction rate constant, which reflects the reaction rate between the agent and phosphorus and is affected by water quality conditions; among them, the reaction rate constant K is calculated by the following formula: ;in, CTP is the total phosphorus concentration in the influent; pH is the pH value of the sewage; T is the temperature; DO is the dissolved oxygen concentration; COD is the chemical oxygen demand; t is the reaction time (unit: min); f is the nonlinear function trained by the XGBoost model.

[0007] Preferably, an alarm system is also provided, which is electrically connected to the central control system. When the phosphorus concentration exceeds a preset range or an abnormal situation occurs during the dosing process, the system will automatically sound an alarm. Compared with the existing method, the present invention has the following beneficial effects: Compared with the traditional dosage calculation method, the chemical phosphorus removal dosing control method for sewage treatment plants proposed in the present invention ensures the optimal phosphorus removal effect by real-time monitoring of water quality parameters and dynamically adjusting the dosage, avoiding excessive or insufficient use of reagents; it can automatically adjust the control strategy according to different water quality conditions, and is suitable for various types of sewage treatment plants and complex water quality changes, enhancing the adaptability and flexibility of the system; at the same time, by optimizing the dosage, it reduces the waste of reagents and reduces operating costs. Accurate dosing control can not only improve the phosphorus removal effect, but also reduce the pollution of the environment caused by residual reagents, thereby improving the environmental benefits of sewage treatment plants.

[0008] The present invention realizes the fully automated control of the chemical phosphorus removal process of the sewage plant, reduces manual intervention, and improves work efficiency. At the same time, the system has self-learning and self-adaptive capabilities, and can continuously optimize the control strategy according to operating experience to ensure the long-term stable operation of the system. DETAILED DESCRIPTION

[0009] The present invention is described in detail below in conjunction with specific implementation modes.

[0010] This embodiment provides a method for controlling the dosing of chemical phosphorus removal in a sewage treatment plant, comprising: S1 installs water quality sensors at key nodes of the sewage plant. The sensors are used to monitor the total phosphorus concentration CTP in the sewage and the target effluent phosphorus concentration CTP in real time. out , pH value, temperature, dissolved oxygen concentration and organic matter concentration; S2 transmits the real-time water quality parameters collected by each sensor to the central control system through the data acquisition unit, and performs denoising, filtering and normalization preprocessing to ensure the quality and consistency of the data; S3 by formula , calculate the dosage Q at the current moment, where: Q is the dosage required (unit: mg / L); CTP is the total phosphorus concentration in the influent (unit: mg / L); CTP out is the target effluent phosphorus concentration (unit: mg / L); CD is the active ingredient concentration of the agent (unit: mg / L); V is the reaction volume (unit: m³); t is the reaction time (unit: min); K is the reaction rate constant, which reflects the reaction speed between the reagent and phosphorus and is affected by water quality conditions.

[0011] The reaction rate constant K is a key parameter affecting the dosage, which reflects the reaction rate between the agent and phosphorus. Since K is affected by many factors (such as pH value, temperature, dissolved oxygen, organic matter concentration, etc.), the traditional fixed value cannot accurately reflect the actual reaction conditions. The present invention uses support vector machine machine learning algorithm to analyze historical data and establishes a dynamic K value prediction model. The model can automatically adjust the K value according to real-time water quality parameters to ensure the accuracy of the dosage.

[0012] Specifically, the reaction rate constant K is calculated by the following formula: ;in, CTP is the total phosphorus concentration in the influent (unit: mg / L); pH is the pH value of the sewage; T is the temperature (unit: °C); DO is the dissolved oxygen concentration (unit: mg / L); COD is the chemical oxygen demand (unit: mg / L); t is the reaction time (unit: min); f is the nonlinear function obtained by XGBoost model training.

[0013] In the actual operation of the above embodiment, the system will monitor the water quality parameters in the sewage in real time and input these parameters into the K prediction model. The model will dynamically adjust the K value according to the current water quality conditions to ensure the accuracy of the dosage. The specific steps are as follows: Real-time data collection: The system collects water quality parameters (such as pH value, temperature, dissolved oxygen, organic matter concentration, etc.) in real time through sensors installed at key nodes of the sewage plant; Data preprocessing: Preprocess the collected real-time data to ensure data quality and consistency.

[0014] K value prediction: input the preprocessed data into the K prediction model to dynamically predict the reaction rate constant K; Dosage calculation: According to the formula , calculate the dosage Q at the current moment; Feedback control: The system monitors the change of phosphorus concentration after adding the drug in real time and transmits the feedback information to the intelligent control model. If the phosphorus concentration does not reach the expected target, the system will automatically adjust the dosage to ensure the best phosphorus removal effect; Self-learning optimization: The intelligent control model has self-learning capabilities and can continuously optimize the control strategy based on historical data and operating experience, gradually improving the accuracy and efficiency of dosing.

[0015] It should be noted that since the XGBoost model is an integrated model composed of multiple decision trees, its internal nonlinear function f is not an explicit mathematical expression, but is obtained through a series of decision rules and weighted combinations. Therefore, we cannot use traditional mathematical formulas to express f, but it can be described in the following form: ;in, N is the number of decision trees in the XGBoost model; It is The weight of a decision tree; It is The predicted value of a decision tree indicates the K value predicted by the decision tree based on the input features.

[0016] In some preferred embodiments, an alarm system is also provided, which is electrically connected to the central control system. When the phosphorus concentration exceeds a preset range or an abnormal situation occurs during the dosing process, the system will automatically sound an alarm to remind the staff to intervene in time, prevent the occurrence of unplanned situations in extreme cases, and avoid operational losses and environmental incidents.

[0017] The present invention realizes the fully automated control of the chemical phosphorus removal process of the sewage treatment plant, ensuring the optimal phosphorus removal effect. The method is not only applicable to municipal sewage treatment plants, but also can be widely used in the fields of industrial wastewater treatment, and has broad application prospects and market potential.

[0018] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for controlling chemical phosphorus removal and dosing in a sewage treatment plant, characterized in that: include: S1 installs water quality sensors at key nodes of the sewage plant. The sensors are used to monitor the total phosphorus concentration CTP in the sewage and the target effluent phosphorus concentration CTP in real time. out , pH value, temperature, dissolved oxygen concentration and organic matter concentration; S2 transmits the real-time water quality parameters collected by each sensor to the central control system through the data acquisition unit, and performs denoising, filtering and normalization preprocessing to ensure the quality and consistency of the data; S3 by formula , calculate the dosage Q at the current moment, where: Q is the dosage of the drug to be added; CTP is the total phosphorus concentration in the influent; CTP out is the target effluent phosphorus concentration; CD is the concentration of the active ingredient of the agent; V is the reaction volume; t is the reaction time; K is the reaction rate constant, which reflects the reaction rate between the agent and phosphorus and is affected by water quality conditions; among them, the reaction rate constant K is calculated by the following formula: ;in, CTP is the total phosphorus concentration in the influent; pH is the pH value of the sewage; T is the temperature; DO is the dissolved oxygen concentration; COD is the chemical oxygen demand; t is the reaction time; and f is the nonlinear function trained by the XGBoost model.

2. A method for controlling chemical phosphorus removal and dosing in a sewage treatment plant according to claim 1, characterized in that: An alarm system is also provided, which is electrically connected to the central control system. When the phosphorus concentration exceeds a preset range or an abnormal situation occurs during the dosing process, the system will automatically sound an alarm.

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