Dynamic pre-oxidation disinfection method for inhibiting generation of halogenated disinfection by-products

Abstract

The invention is applicable to the technical field of water treatment and drinking water disinfection, and provides a dynamic pre-oxidation disinfection method for inhibiting generation of halogenated disinfection byproducts, which comprises the following steps: raw water pretreatment: treating raw water to reduce turbidity and organic matters; pre-oxidation treatment: adding a pre-oxidant potassium ferrate into the pretreated raw water to carry out a pre-oxidation reaction, and removing generated iron flocs after the pre-oxidation reaction; chlorine disinfection treatment: adding a sodium hypochlorite solution into the pre-oxidized water for chlorine disinfection. According to the method, potassium ferrate pre-oxidation and a disinfectant (sodium hypochlorite) are combined for use, an online monitoring and feedback regulation system is combined, a disinfection process is dynamically optimized to reduce generation of halogenated disinfection byproducts (DBPs) in drinking water, and the method is suitable for advanced purification and safety guarantee of drinking water treatment in urban and rural water plants, emergency water purification devices and micro-polluted water sources.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment and drinking water disinfection, and in particular relates to a dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products. Background Art

[0002] Emerging micropollutants (ECs) are a class of pollutants that have garnered widespread attention in recent years but have yet to be fully regulated or included in traditional pollutant control systems. They are characterized by low concentrations, high risk, wide distribution, and resistance to degradation. Antibiotics, a key component of these emerging micropollutants, have been frequently detected in water environments. Traditional water purification processes (coagulation, sedimentation, filtration, etc.) have low removal rates for these trace organic pollutants. Therefore, the current project has added a pre-oxidation disinfection step using chlorine-containing disinfectants (such as chlorine gas and sodium hypochlorite) to further remove ECs.

[0003] While chlorine-containing disinfectants do remove some ECs, they also pose a new problem: when chlorine-containing disinfectants come into contact with aromatic and aniline organic matter (such as humic acid in natural organic matter (NOM)) in water, they produce a series of chlorinated disinfection byproducts (DBPs) with carcinogenic, mutagenic, and teratogenic effects, posing a serious threat to drinking water safety and health. The most common disinfection byproducts (DBPs) produced by chlorination of drinking water are trihalomethanes (THMs) and haloacetic acids (HAAs). Subsequent studies have also identified a number of newer, more toxic DBPs, including iodinated trihalomethanes (I-THMs), halogenated acetonitriles (HANs), haloketones (HKs), and chloropicrin. Furthermore, when the bromide or iodide ion content in source water is high, halogen substitution reactions occur during the chlorination process, forming brominated or iodinated DBPs, which are far more toxic than chlorinated DBPs. Switching to chloramination disinfection can significantly reduce the generation of THMs and HAAs. Therefore, some water plants use pre-chlorination + post-chloramination to control conventional DBPs. However, chloramination disinfection will produce nitrogen-containing DBPs such as halogenated acetonitrile, which are even more toxic.

[0004] In summary, when water containing micropollutants such as antibiotics is disinfected with chlorine, the generation of disinfection by-products and their toxicity have become important issues that need to be addressed urgently. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products, aiming to solve the problems raised in the above background technology.

[0006] The embodiment of the present invention is achieved by providing a dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection byproducts, comprising the following steps: Raw water pretreatment: Treat raw water to reduce turbidity and organic matter; Pre-oxidation treatment: adding pre-oxidant potassium ferrate to the pre-treated raw water to carry out pre-oxidation reaction. After the pre-oxidation reaction, the generated iron flocs are removed; Chlorine disinfection: Add sodium hypochlorite solution to the water after pre-oxidation treatment for chlorine disinfection.

[0007] Preferably, in the step of treating the raw water to reduce turbidity and organic matter, the treatment includes sedimentation and filtration.

[0008] Preferably, in the step of adding a pre-oxidizing agent potassium ferrate to the pretreated raw water for pre-oxidation reaction, the addition concentration of potassium ferrate is 1-5 mg / L, and the oxidation contact time is 10-30 minutes.

[0009] Preferably, in the step of removing the generated iron flocs, sedimentation and sand filtration are adopted.

[0010] Preferably, in the step of adding sodium hypochlorite solution to the pre-oxidation treated water for chlorine disinfection, the sodium hypochlorite addition concentration is 1-3 mg / L, the chlorination contact time is not less than 30 minutes, and the residual chlorine concentration is controlled at 0.1-0.5 mg / L.

[0011] Preferably, during the chlorine disinfection step, the pH is controlled at 6.5-7.5.

[0012] Another object of an embodiment of the present invention is to provide a dynamic pre-oxidation disinfection system for inhibiting the generation of halogenated disinfection by-products, which is used to implement the above-mentioned dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products, comprising: The raw water unit is used to pre-treat the raw water, detect the raw water parameters, and calculate the dosage of the pre-treating agent, which is potassium ferrate; Potassium ferrate pre-oxidation unit, the raw water is transported to the potassium ferrate pre-oxidation unit through a lifting pump, and the raw water is pre-oxidized. The potassium ferrate pre-oxidation unit monitors UV in real time. 254 , TOC, conductivity parameter feedback to adjust the dosage of potassium ferrate; Chlorination disinfection unit: the water after pre-oxidation treatment is transported to the chlorination disinfection unit to perform chlorination disinfection on the raw water. The chlorination disinfection unit adjusts the dosage of sodium hypochlorite by real-time monitoring of residual chlorine and pH parameter feedback; Subsequent treatment units are used for deep treatment to remove residual by-products and improve water quality stability.

[0013] An embodiment of the present invention provides a dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products. A two-stage pre-oxidation unit is provided. In the first-stage pre-oxidation, potassium ferrate is added before coagulation to efficiently degrade DBPs precursors such as natural organic matter and antibiotic pollutants. The second-stage pre-oxidation is optionally arranged after sand filtration, and a trace amount of potassium ferrate is added to inhibit microbial regeneration and residual organic pollutants. In addition, an Fe(OH)3 floc recovery device can be provided to resource the sedimentation tank sludge, which can be used as a coagulant aid in the subsequent coagulation unit and can also be regenerated as ferrate for recycling. This combined process is suitable for a modular integrated system and is convenient for flexible deployment in small rural water purification stations or emergency water purification vehicles. The disinfection system combines online water quality monitoring and intelligent feedback control to achieve dynamic optimization of reagent addition. In the raw water adjustment stage, a potassium ferrate addition system is set up to 254 Real-time monitoring of key water quality indicators such as TOC and conductivity is performed, and the K2FeO4 dosage is adjusted to reduce organic precursors. During the disinfection stage, the sodium hypochlorite dosage is controlled through feedback from residual chlorine and pH monitoring to ensure the minimum effective disinfection dose while suppressing the formation of disinfection by-products. The entire system is managed by a PLC automation control platform with a multi-parameter linkage adjustment algorithm that can quickly respond to raw water anomalies such as sudden increases in turbidity or fluctuations in pollutants. It is highly adaptable in terms of application scenarios. For areas with severe antibiotic pollution, potassium ferrate pre-oxidation can effectively break its molecular structure, reducing the formation of toxic byproducts in subsequent chlorination reactions at the source. In emergency drinking water treatment, solid potassium ferrate premixing and sodium hypochlorite integrated modular equipment can be used, combined with an online control system to achieve rapid production and safe water output. For areas with high bromine or high iodine water sources, the above method and system can also be combined with a halide ion control module to prevent the formation of highly toxic Br-DBPs or I-DBPs. In actual application tests, the above method and system significantly reduced the generation of major halogenated disinfection by-products. The concentration of trichloromethane (TCM) was reduced by more than 65% compared with the conventional chlorination process, and the nitrogen-containing disinfection by-products such as halogenated acetonitriles (such as DCAN) was reduced by more than 70%. The overall cytotoxicity risk index of the effluent decreased by about 52%, fully demonstrating the significant advantages of the embodiments of the present invention in deep purification and safety assurance of drinking water. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The results of the effect of NaClO dosage on DBPs generation from SMZ in the NaClO-only process provided in Example 2 of the present invention are as follows; Figure 2 The results of the effect of NaClO dosage on DBPs generation in SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention are as follows; Figure 3 The results of the effect of chlorination time on DBPs generation from SMZ in the NaClO process alone provided in Example 2 of the present invention are as follows; Figure 4 The results of the effect of K2FeO4 pre-oxidation and post-chlorination time on the generation of DBPs from SMZ provided in Example 2 of the present invention; Figure 5 The results of the effect of pH on the generation of DBPs from SMZ in the NaClO process alone provided in Example 2 of the present invention are as follows; Figure 6 The results of the effect of pH on the generation of DBPs from SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention; Figure 7 The results of the effect of reaction temperature on the generation of DBPs from SMZ in the NaClO process alone provided in Example 2 of the present invention; Figure 8 The results of the effect of reaction temperature on the generation of DBPs from SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention; Figure 9 The results of the effect of FA dosage on DBPs generation in SMZ in the NaClO process alone provided in Example 2 of the present invention are as follows; Figure 10 The results of the effect of FA dosage on DBPs generation in SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention; Figure 11 The results of the effect of KBr dosage on DBPs generation from SMZ in the NaClO process alone provided in Example 2 of the present invention are as follows; Figure 12 The results of the effect of KBr dosage on DBPs generation in SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention; Figure 13 The results of the effect of KI dosage on DBPs generation in SMZ in the NaClO process alone provided in Example 2 of the present invention are as follows; Figure 14 The results of the effect of KI dosage on DBPs generation in SMZ after K2FeO4 pre-oxidation provided in Example 2 of the present invention; Figure 15 The results of the effect of K2FeO4 dosage on DBPs generation in SMZ provided in Example 2 of the present invention; Figure 16 This is a structural diagram of a dynamic pre-oxidation disinfection system for inhibiting the generation of halogenated disinfection by-products provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0016] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0017] Example 1: A dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products, comprising the following steps: (1) Raw water pretreatment: perform routine sedimentation, filtration and other treatments on the water source to reduce turbidity and some organic matter; (2) Pre-oxidation treatment: Add pre-oxidant (potassium ferrate) to the water to be treated for pre-oxidation reaction. Potassium ferrate is prepared as a solid agent and added in the form of solution. Pre-oxidation contact for a period of time can initially degrade the molecular structure of pollutants. At the same time, the pre-oxidation stage converts some difficult-to-degrade organic matter into a form that is easier to remove, and can reduce some DBPs precursors in the subsequent disinfection stage. For potassium ferrate pre-oxidation, FeO4 2- It will be reduced to Fe(OH)3 precipitation, which helps to further remove organic matter; after pre-oxidation, the iron flocs that may be generated can be removed by precipitation, sand filtration, etc., so as not to affect the subsequent processes; the potassium ferrate dosing system is introduced into the raw water regulating tank, and the online UV 254 , TOC or conductivity and other parameters feedback to adjust the K2FeO4 dosage, the addition concentration range is 1-5 mg / L, and the oxidation contact time is controlled at 10-30 minutes; (3) Chlorine disinfection: Sodium hypochlorite solution is added to the water after pre-oxidation treatment for chlorine disinfection. The dosage of NaClO is in accordance with the standard for conventional drinking water disinfectants, and the typical range is mg / L (adjusted according to the water quality after pre-oxidation). The residual chlorine in the water reacts with the pre-oxidation products and residual organic pollutants to achieve disinfection and sterilization while further degrading the pollutants; the chlorine contact reaction time is controlled to ensure that the residual chlorine reacts fully; slight stirring can be maintained during the reaction to ensure uniform distribution of the agent; real-time monitoring points for residual chlorine and pH are set in the disinfection contact tank, and the dosage of NaClO is intelligently controlled according to the feedback signal to achieve the minimum effective dosage principle; after the water is discharged from the disinfection contact tank, if the residual chlorine is too high, an appropriate amount of dechlorinating agent such as sodium thiosulfate can be added to neutralize it; the sodium hypochlorite dosage concentration is 1-3 mg / L, the chlorination contact time is not less than 30 minutes, and the residual chlorine concentration is controlled at 0.1-0.5 mg / L. The pH condition is maintained between 6.5-7.5 to take into account both oxidation efficiency and disinfection by-product control effects; (4) After the above-mentioned pre-oxidation + chlorine disinfection combined process, the effluent enters the subsequent deep treatment. The entire system is controlled by PLC and has a multi-parameter linkage adjustment algorithm that can automatically respond to water quality changes (such as sudden changes in turbidity, fluctuations in micropollutant concentrations, etc.).

[0018] Example 2: Analysis of the influence of different factors on the disinfection effect of the pre-oxidation-sodium hypochlorite disinfection combined process: 1. Dosage of sodium hypochlorite: Figure 1 and Figure 2 As shown in the figure, increasing the NaClO dosage accelerates the degradation of target pollutants. In the disinfection reactions of NaClO alone and K2FeO4+NaClO, the degradation rate of the pollutant sulfamethoxazole (SMZ) can be improved and approach 100% with the increase of NaClO concentration. However, higher sodium hypochlorite dosage will also promote the formation of DBPs. For example, the production of trichloromethane (TCM) and trichloroacetone (TCP) increases significantly with the increase of NaClO disinfectant dosage. The use of potassium ferrate pre-oxidation in the embodiment of the present invention can alleviate the DBPs problem under high sodium hypochlorite dosage to a certain extent. Potassium ferrate pre-oxidation can especially inhibit the excessive formation of some DBPs. 2. Contact time: Figure 3 、 4 As shown in the figure, extending the chlorine contact reaction time is beneficial to the complete degradation of the target pollutants. For example, when the chlorine disinfection reaction time reaches 480 minutes, the SMZ degradation rate can exceed 98%. However, the change of DBPs generation with reaction time is not completely linear: under longer reaction times, the effects of different processes on various types of DBPs show different trends of increase and decrease. Properly extending the contact time ensures thorough disinfection, while the amount of DBPs generated needs to be comprehensively considered. Pre-oxidation optimization can reduce the adverse effects of long-term contact. 3. pH value: Figure 5 、 6 As shown in the figure, the pH of water affects the disinfection reaction rate and the types of by-products. Generally speaking, hypochlorous acid (HOCl) has more hypochlorite ions (OCl) under neutral to alkaline conditions. - ) form, the oxidation capacity is slightly reduced, but the production of some DBPs (such as chloroform) is actually higher at neutral pH. Experiments have found that the degradation rate of SMZ is highest when the pH is close to neutral. When NaClO is disinfected alone, the total amount of DBPs increases with increasing pH, while the addition of potassium ferrate pre-oxidation and the combined process control DBP production at different pH levels, without a significant increase. Therefore, it is preferred to adjust the water pH to around neutral for pre-oxidation and disinfection to achieve a balance between degradation efficiency and DBP control. 4. Temperature: Figure 7 、 8As shown, increasing temperature generally accelerates the rate of chemical reactions. Experiments have shown that as the water temperature increases, the degradation rate of SMZ increases. For NaClO disinfection alone, temperature significantly affects the generation of certain DBPs (such as TCP). Every 10°C increase in temperature may increase the amount of TCP produced by about 50%. In contrast, the potassium ferrate pre-oxidation combined process is less sensitive to temperature changes, and DBPs generation is less affected by temperature fluctuations. Therefore, the method provided in the embodiment of the present invention is more applicable under room temperature conditions. At low temperatures, the contact time can be appropriately extended to ensure the effect. 5. Natural organic matter (represented by fulvic acid FA): such as Figure 9 、 10 As shown, dissolved organic matter in water competes for disinfectants and can serve as a precursor for DBPs. Studies have found that when FA is added to water to simulate NOM, the SMZ degradation rate in the ozone pre-oxidation process drops from 98.69% to 85.11%, a decrease of 13.58%, indicating that FA significantly inhibits O3 pre-oxidation. Experimental results show that potassium ferrate pre-oxidation is relatively more resistant to FA disturbances, and SMZ removal is less affected. On the other hand, the presence of FA promotes the formation of some halogenated organic byproducts. However, in the potassium ferrate pre-oxidation combined process, the formation of byproducts such as dichloroacetonitrile (DCAN) decreases continuously with increasing FA concentration. Therefore, when applying the methods and systems proposed in embodiments of the present invention to water containing high organic matter, it may be appropriate to consider increasing the dosage of potassium ferrate pre-oxidant to offset the adverse effects of natural organic matter. 6. Halogen ions (Br - , I - ):like Figures 11 to 14 As shown in the figure, the presence of bromide and iodide ions in the source water will change the disinfection reaction pathway, resulting in the formation of brominated or iodinated DBPs. Experiments have shown that increasing Br - The concentration of Br-DBPs promoted the formation of total Br-DBPs and inhibited the formation of Cl-DBPs in each process. Specifically, under the sodium hypochlorite disinfection process alone and the potassium ferrate pre-oxidation + sodium hypochlorite disinfection process, the Br-DBPs - As the concentration increases, the production of typical Cl-DBPs (such as TCM, TCP, and DCP) decreases, reflecting the bromine substitution effect; at the same time, brominated by-products will appear, such as bromochloroacetonitrile (BCAN), which is only detected in the combination of potassium ferrate pre-oxidation and sodium hypochlorite disinfection; I - When NaClO is present, the concentrations of various DBPs produced by disinfection alone are very low, but after adding potassium ferrate for pre-oxidation, Cl-DBPs decrease and iodine-DBP increases; in general, under high Br - / I -In water quality, the method provided by the embodiment of the present invention can still degrade the target pollutants, but it will generate a certain amount of more toxic Br-DBPs and I-DBPs, which needs further optimization (such as increasing the adsorption / removal of Br - , I - units or use more appropriate pretreatment) to ensure the safety of produced water; 7. Dosage of pre-oxidant: Figure 15 As shown in the figure, the amount of pre-oxidant directly affects the removal of SMZ and the degree of conversion of DBPs precursors. It is recommended to adjust the pre-oxidant dosage according to the water quality: the dosage of potassium ferrate is 1-5 mg / L. Increasing the dosage of K2FeO4 can improve the degradation rate of SMZ (about 7.4% when increasing from 0 to 5 mg / L, close to complete degradation). At the same time, when K2FeO4 is sufficient, it has a significant inhibitory effect on the formation of DBPs - for example, TCM, DCP, and TCP decreased by 65.6%, 66.9%, and 83.5% with the increase of K2FeO4 dosage. However, it should be noted that excessive potassium ferrate may increase the formation of nitrogen-containing by-product DCAN (increased by about 134.1%). Using potassium ferrate and controlling it within the optimized dosage range can not only ensure the maximum degradation of pollutants, but also effectively inhibit the formation of by-products.

[0019] In summary, potassium ferrate pre-oxidation combined with sodium hypochlorite provides the best control of disinfection byproducts, significantly reducing the production of halogenated hydrocarbons and halogenated nitriles (DBPs). Taking the scenario of increasing chlorine dosage as an example, when NaClO is used for disinfection alone, TCM and TCP production increase by approximately 114.2% and 160.2%, respectively. However, with K₂FeO₄ pre-oxidation, TCM increases by only 133.6% and TCP by 23.8%. Dichloroacetonitrile (DCAN) is almost nonexistent during chlorine disinfection alone, but increases only slightly by 3.8% after potassium ferrate pre-oxidation. This indicates that potassium ferrate pre-oxidation effectively inhibits the production of emerging organic byproducts during chlorine disinfection. Therefore, the combination of potassium ferrate pre-oxidation and sodium hypochlorite disinfection employed in the present invention can achieve a balance between pollutant degradation and DBP control in most cases.

[0020] Example 3, as Figure 16 As shown, a structural diagram of a dynamic pre-oxidation disinfection system for inhibiting the generation of halogenated disinfection by-products provided by an embodiment of the present invention is provided, which is used to implement the above-mentioned dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products, including: Raw water unit: The water to be treated containing micropollutants (such as antibiotics) first enters the raw water regulating tank or pipeline, where water quality parameters (pollutant concentration, pH, bromine / iodide ion content, etc.) are measured to determine the pretreatment dosage. The raw water is then transported to the pre-oxidation unit through a lift pump; Potassium ferrate pre-oxidation unit: The pre-oxidant dosing device introduces potassium ferrate or ozone gas into the pre-oxidation reactor. The pre-oxidation reactor can be a reaction tank equipped with a stirrer or a tubular mixer to ensure that the pre-oxidant and the raw water are fully in contact and reacted. After a period of pre-oxidation contact time, the target pollutants in the water are partially oxidized and degraded, and some DBP precursors are converted or removed. If potassium ferrate is used, the Fe(III) flocs generated at this stage can be removed by setting up a sedimentation tank / sand filter to ensure smooth subsequent processes. Chlorination (NaClO) disinfection unit: The water after pre-oxidation treatment flows into the chlorine disinfection contact tank. Sodium hypochlorite solution is added by a metering pump at the inlet and mixed with the water according to the set dosage. The contact tank provides sufficient residence time to complete the disinfection reaction and deep oxidation of pollutants. A stirring device can be set in the tank to maintain uniform reaction. The water quality after pre-oxidation is easier to disinfect. The chlorine dosage is relatively low to meet the residual chlorine requirements. A residual chlorine monitoring point is set at the end of the tank. If necessary, a dechlorinating agent (such as sodium bisulfite) is added for dechlorination to avoid excessive residual chlorine. Subsequent treatment unit: The disinfected effluent is collected into the clear water tank and can be further treated by sand filtration, activated carbon adsorption and other deep treatments to remove residual by-products and improve water quality stability (optional). The entire system is equipped with an automatic control and monitoring system: online monitoring of pre-oxidant dosage, residual chlorine concentration, oxidation-reduction potential (ORP), effluent water quality indicators, etc., to achieve coordinated optimization of each unit. Through PLC control, the dosage of pre-oxidant and disinfectant can be automatically adjusted according to changes in water quality to always maintain the best pollutant removal and DBP control effect.

[0021] In summary, the method and system provided by the embodiments of the present invention have a two-stage series structure: the pre-oxidation stage is mainly responsible for reducing the concentration of pollutants and lowering the activity of DBP precursors; the disinfection stage completes the final sterilization and oxidation of residual pollutants, while minimizing the generation and toxicity of DBPs on the basis of pretreatment; the system has clear logic, and the various functional units are closely connected, with stable, safe and efficient operation characteristics, and is suitable for deep purification treatment of PPCPs contaminated drinking water plants and source water.

[0022] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products, characterized in that: The following steps are involved: Raw water pretreatment: Treat raw water to reduce turbidity and organic matter; Pre-oxidation treatment: adding pre-oxidant potassium ferrate to the pre-treated raw water to carry out pre-oxidation reaction. After the pre-oxidation reaction, the generated iron flocs are removed; Chlorine disinfection: Add sodium hypochlorite solution to the water after pre-oxidation treatment for chlorine disinfection.

2. The dynamic pre-oxidation disinfection method for suppressing the generation of halogenated disinfection by-products according to claim 1, wherein In the step of treating the raw water to reduce turbidity and organic matter, the treatment includes sedimentation and filtration.

3. The dynamic pre-oxidation disinfection method for suppressing the generation of halogenated disinfection by-products according to claim 1, wherein In the step of adding the pre-oxidizing agent potassium ferrate to the pretreated raw water for pre-oxidation reaction, the addition concentration of the potassium ferrate is 1-5 mg / L, and the oxidation contact time is 10-30 minutes.

4. The dynamic pre-oxidation disinfection method for suppressing the generation of halogenated disinfection by-products according to claim 1, wherein In the step of removing the generated iron flocs, sedimentation and sand filtration are adopted.

5. The dynamic pre-oxidation disinfection method for suppressing the generation of halogenated disinfection by-products according to claim 1, wherein In the step of adding sodium hypochlorite solution to the pre-oxidation treated water for chlorine disinfection, the sodium hypochlorite addition concentration is 1-3 mg / L, the chlorination contact time is not less than 30 minutes, and the residual chlorine concentration is controlled at 0.1-0.5 mg / L.

6. The dynamic pre-oxidation disinfection method for suppressing the generation of halogenated disinfection by-products according to claim 1, wherein During the chlorine disinfection step, the pH is controlled at 6.5-7.

5.

7. A dynamic pre-oxidation disinfection system for inhibiting the generation of halogenated disinfection by-products, for implementing the dynamic pre-oxidation disinfection method for inhibiting the generation of halogenated disinfection by-products as described in any one of claims 1 to 6, characterized in that: include: The raw water unit is used to pre-treat the raw water, detect the raw water parameters, and calculate the dosage of the pre-treating agent, which is potassium ferrate; Potassium ferrate pre-oxidation unit, the raw water is transported to the potassium ferrate pre-oxidation unit through a lifting pump, and the raw water is pre-oxidized. The potassium ferrate pre-oxidation unit monitors UV in real time. 254 , TOC, conductivity parameter feedback to adjust the dosage of potassium ferrate; Chlorination disinfection unit: the water after pre-oxidation treatment is transported to the chlorination disinfection unit to perform chlorination disinfection on the raw water. The chlorination disinfection unit adjusts the dosage of sodium hypochlorite by real-time monitoring of residual chlorine and pH parameter feedback; Subsequent treatment units are used for deep treatment to remove residual by-products and improve water quality stability.

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