Intelligent method for controlling hydrogen sulfide and methane in sewer networks with activated urea peroxide

Abstract

The present application belongs to the technical field of sewage treatment, and provides a smart method for controlling hydrogen sulfide and methane in sewage pipe network by activated urea peroxide. The method comprises adding urea peroxide to the sewage pipe network to treat the sewage. The present application forms various free radicals by in-situ activation of urea peroxide, destroys the extracellular polymeric substance EPS of sulfate-reducing bacteria (SRB) and methanogens (MA), affects the activity of intracellular enzymes, inhibits the generation of hydrogen sulfide and methane gas in sewage from the source, and reduces the corrosion of the sewage pipe network. The inhibition effect on hydrogen sulfide and methane is more persistent, and 85% of sulfides and 82% of methane gas can be inhibited in the short term, and the inhibition state is still maintained for a period of time. A smart system is established by connecting an online monitoring device, a dosing execution device and a control center into a closed-loop control system, and a dosing optimization model and a regulation model are adopted to realize intelligent optimization control of hydrogen sulfide and methane.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a smart method for controlling hydrogen sulfide and methane in wastewater pipe networks by activating urea peroxide. Background Technology

[0002] Wastewater pipe networks serve as crucial connecting points between urban residential buildings and wastewater treatment plants, responsible for wastewater collection and transportation. Scientific operation and maintenance of these networks are paramount, with issues such as pipe corrosion, odor, and carbon emissions being particularly prominent. The abundant sulfides and organic matter present in wastewater pipe networks, under the action of sulfate-reducing bacteria (SRB) and methanogens (MA), produce large amounts of hydrogen sulfide and methane gas. Corrosion caused by hydrogen sulfide gas is a major culprit for the high costs and environmental safety hazards of wastewater pipe network operation and maintenance, representing a core issue in network maintenance. Furthermore, the foul odor and health threats posed by hydrogen sulfide, as well as the carbon emissions from methane gas, cannot be ignored, and several safety incidents caused by hydrogen sulfide poisoning have already occurred.

[0003] Currently, chemical dosing is a common method for controlling hydrogen sulfide and methane in sewage pipe networks. It controls the production of hydrogen sulfide and methane by removing already generated gases or inhibiting bacterial activity, achieving methane emission reduction while controlling hydrogen sulfide. Commonly used chemical dosing agents include iron salts, alkalis, nitrates, and oxygen. However, this method is costly and carries the risk of hydrogen sulfide backflow. Chemicals that control hydrogen sulfide and methane production by inhibiting bacterial activity include free nitrites, ferrates, and polyoxometalates (POMs), but issues with bacterial resistance and downstream environmental impact remain. Chinese patent CN116854232A discloses adding iron ions to sewage pipe networks to form ferrous sulfide particles on the surface of sediments. Simultaneously, oxygen-containing gas is used to aerate the sewage pipe network, causing the ferrous sulfide particles to react with dissolved oxygen to form hydroxyl radicals. These hydroxyl radicals oxidize sulfides in the sewage pipe network and inhibit the activity of SRB and MA. Chinese patent CN117003344 discloses an electrochemical sewage pipe network sulfide control device and method. It utilizes chemical reactions at the anode and cathode to achieve long-term in-situ generation of reagents, eliminating safety hazards during transport and storage, effectively controlling sulfides, and eliminating the generation of hydrogen sulfide gas. A specific device is used to control the position within the sewage pipe network, and different products are regulated according to the characteristics of the sewage, reducing the operation and maintenance costs of the sewage pipe network. Chinese patent CN114180701A discloses a method for degrading organic arsenic pollution in water by activating ferrous peroxide. Urea peroxide and ferrous ions are added to water containing organic arsenic. The urea peroxide and ferrous ions undergo a Fenton-like reaction to generate hydroxyl radicals, degrading the organic arsenic in the water into arsenate, thereby removing organic arsenic pollution from the water.

[0004] Urea peroxide (UHP) is an adduct of hydrogen peroxide and urea, with an active oxygen content of 36.2%, higher than that of calcium peroxide, sodium perborate, and sodium percarbonate. Urea peroxide is a good alternative to high-concentration hydrogen peroxide and organic peroxyacids. It is non-toxic and pollution-free, and is a novel, efficient, multifunctional, broad-spectrum, safe, and easy-to-use green solid disinfectant. Low-cost urea peroxide can be obtained using electrochemical methods, and combining it with urine wastewater management can further reduce costs, demonstrating extremely broad development potential and significant development value.

[0005] This invention aims to address the problems of insufficient environmental protection, low economic efficiency, and lack of intelligent control methods in existing technologies by providing a smart method for controlling hydrogen sulfide and methane in sewage pipe networks. Summary of the Invention

[0006] The purpose of this invention is to provide a smart method for controlling hydrogen sulfide and methane in sewage pipe networks by activating urea peroxide, which addresses the shortcomings of existing technologies.

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

[0008] This invention provides a smart method for controlling hydrogen sulfide and methane in sewage pipe networks by activating urea peroxide, comprising the following steps:

[0009] Urea peroxide is added to the sewage pipe network to treat the sewage.

[0010] As a preferred option, the method also includes adding the activator into the sewage network.

[0011] Preferably, the activator is a substance capable of activating urea peroxide to generate hydroxyl radicals, superoxide radicals, and singlet oxygen.

[0012] Preferably, the molar volume ratio of the urea peroxide dosage to the wastewater is 1–3 mmol: 1 L.

[0013] Preferably, the molar volume ratio of the activator to the wastewater is 0.1–0.3 mmol: 1 L.

[0014] Preferably, the processing time is 5 to 8 hours.

[0015] As a preferred option, after adding urea peroxide to the sewage pipe network, the method also includes quantitative control of the dosage through a smart system;

[0016] The intelligent system includes an online monitoring device, a drug delivery device, and a control center;

[0017] The online monitoring device monitors the wastewater online to obtain a dynamic water quality database; the dynamic water quality database includes pH value, H2S concentration, sulfate concentration, COD, and flow rate;

[0018] The dosing device includes a storage tank, a dosing pipeline, and a dosing port. The storage tank is connected to the dosing port via the dosing pipeline. The dosing pipeline is equipped with a dosing metering pump, an electric valve, and a detector.

[0019] The control center includes an industrial computer and a PLC control system. The dosing metering pump, electric valve, detector, and online monitoring device are respectively connected to the industrial computer, and the industrial computer is connected to the PLC control system.

[0020] The process of quantitative drug administration controlled by the intelligent system includes the following steps:

[0021] S1. Water quality dynamic database acquisition: Collects the pH value, H2S concentration, sulfate concentration, COD and flow rate of wastewater through online monitoring devices and transmits them to the industrial control computer;

[0022] S2. Model Calculation: The industrial control computer uses the water quality dynamic database to perform a dosing optimization model to obtain the optimized dosing amount and predicted H2S concentration.

[0023] S3. Dosing Execution: The industrial control computer transmits the optimized dosage to the PLC control system, which then controls the dosing execution device to perform the dosing.

[0024] S4. Detection and Feedback: The industrial control computer compares the H2S concentration in the water quality dynamic database with the H2S concentration limit value, which is 10ppm. When the H2S concentration is higher than the H2S concentration limit value, the industrial control computer calculates the dosage of the supplementary drug according to the adjustment model and transmits it to the PLC control system. The PLC control system controls the dosing execution device to perform the supplementary drug dosing.

[0025] Preferably, the drug dosing optimization model is based on the drug dosing inhibition model to obtain the relationship between H2S concentration and urea peroxide dosage, and performs optimization iteration with the baseline value of urea peroxide dosage, and solves the minimization objective function through a QP solver;

[0026] The objective function is: Among them, [H2S] t The predicted H2S concentration is given in ppm and μ. t ω1 represents the dosage of urea peroxide, in kg / h; ω2 represents the weighting parameter for H2S inhibition and cost savings.

[0027] The drug administration inhibition model is: and Where, μ SRBThe specific growth rate of sulfate-reducing bacteria, h -1 μ max,SRB The maximum specific growth rate of sulfate-reducing bacteria, h -1 ;[SO4 2- SO4 in wastewater 2- Concentration, mg / L; Ks is the sulfate half-saturation constant, mg / L; [COD] is the organic matter concentration, mg / L; K COD [H2O2] is the half-saturation constant of the organic compound, in mg / L; [H2O2] is the dosage in μg / L. t The concentration of hydrogen peroxide released by urea peroxide, mg / L; K I，SRB [SRB] represents the drug inhibition constant, in mg / L; [SRB] represents the number of viable SRB cells per unit volume of wastewater, in cells / mL.

[0028] The baseline value for the urea peroxide dosage is based on Calculate, where C 最佳 1–3 mmol / L; Q in The flow rate of the wastewater is m. 3 / h; This is the ratio of the sulfate concentration in actual wastewater to the sulfate concentration in the experimental baseline, i.e. The experimental baseline sulfate concentration

[0029] Preferably, the adjustment model is as follows: Where, μ PID K represents the dosage of urea peroxide supplementation, in kg / h; e(t) represents the concentration deviation of H2S, in ppm; d K represents the differential coefficient; p K is the proportionality coefficient. i is the integral coefficient.

[0030] The beneficial effects of this invention include the following:

[0031] 1) This invention utilizes in-situ activation of urea peroxide to generate hydroxyl radicals, superoxide radicals, singlet oxygen, etc. The synergistic effect of these multiple free radicals destroys the extracellular polymers (EPS) of SRB and MA, and affects the activity of intracellular enzymes, thereby achieving a bactericidal effect. This inhibits the generation of hydrogen sulfide and methane gas in sewage from the source, reducing the corrosion of sewage pipe networks and carbon emissions. Urea peroxide can gradually release hydrogen peroxide, oxidizing sulfides in sewage into elemental sulfur or sulfur oxides, thus preventing the generation of hydrogen sulfide.

[0032] 2) Compared with traditional chemical dosing methods, the method of the present invention can suppress 85% of hydrogen sulfide and 82% of methane gas in a short period of time, and can maintain the suppression state for a period of time, with a lower dosage. The by-products of urea peroxide are simple and non-toxic, reducing the treatment burden of downstream sewage and achieving more favorable economic and environmental benefits in the construction of integrated operation and maintenance of sewage pipe networks.

[0033] 3) Establish an intelligent system by connecting online monitoring devices, dosing execution devices, and a control center into a closed-loop control system. Employ dosing optimization and adjustment models, and form a closed loop of "perception-analysis-decision-execution" through data monitoring → optimization decision-making → dosing execution → effect feedback → parameter calibration to achieve intelligent optimization control of hydrogen sulfide and methane. Attached Figure Description

[0034] Figure 1 C represents the hydrogen sulfide production rate in Example 1 and Comparative Example 1, where C represents Comparative Example 1 and RU represents Example 1.

[0035] Figure 2 C represents the methane production rate in Example 1 and Comparative Example 1, where C represents Comparative Example 1 and RU represents Example 1. Detailed Implementation

[0036] This invention provides a smart method for controlling hydrogen sulfide and methane in sewage pipe networks by activating urea peroxide, comprising the following steps:

[0037] Urea peroxide is added to the sewage pipe network to treat the sewage.

[0038] In this invention, it is preferable to further include adding an activator to the sewage pipe network. When the sum of the concentrations of total Fe, total Cu, total Mn, and total Cr in the sewage of the sewage pipe network is less than 10 mg / L, the method further includes adding an activator to the sewage pipe network to increase the activation effect of urea peroxide.

[0039] In this invention, the activator is preferably a substance capable of activating urea peroxide to generate hydroxyl radicals, superoxide radicals and singlet oxygen.

[0040] In this invention, the activator is preferably a ferrous salt.

[0041] In this invention, the ferrous salt is preferably ferrous chloride.

[0042] In this invention, the molar volume ratio of urea peroxide to wastewater is preferably 1-3 mmol:1L, more preferably 1.5-2.5 mmol:1L, and even more preferably 2 mmol:1L.

[0043] In this invention, the molar volume ratio of the activator to the wastewater is preferably 0.1-0.3 mmol:1L, more preferably 0.15-0.25 mmol:1L, and even more preferably 0.2 mmol:1L.

[0044] In this invention, the processing time is preferably 5 to 8 hours, and more preferably 6 to 7 hours.

[0045] In this invention, the activator and urea peroxide are preferably added upstream of the sewage system, and more preferably at a pumping station, wet well, manhole, or pipeline.

[0046] In this invention, after adding urea peroxide to the sewage pipe network, it is preferable to further include quantitative control of the dosage through an intelligent system;

[0047] The intelligent system preferably includes an online monitoring device, a drug delivery device, and a control center;

[0048] The online monitoring device preferably monitors wastewater online to obtain a dynamic water quality database; the dynamic water quality database preferably includes pH value, H2S concentration, sulfate concentration, COD, and flow rate;

[0049] The dosing device preferably includes a storage tank, a dosing pipeline, and a dosing port. The storage tank is preferably connected to the dosing port via the dosing pipeline. The dosing pipeline is preferably equipped with a dosing metering pump, an electric valve, and a detector.

[0050] The control center preferably includes an industrial computer and a PLC control system. The dosing metering pump, electric valve, detector, and online monitoring device are preferably connected to the industrial computer, and the industrial computer is preferably connected to the PLC control system.

[0051] The process of quantitative drug administration controlled by the intelligent system preferably includes the following steps:

[0052] S1. Water quality dynamic database acquisition: Collects the pH value, H2S concentration, sulfate concentration, COD and flow rate of wastewater through online monitoring devices and transmits them to the industrial control computer;

[0053] S2. Model Calculation: The industrial control computer uses the water quality dynamic database to perform a dosing optimization model to obtain the optimized dosing amount and predicted H2S concentration.

[0054] S3. Dosing Execution: The industrial control computer transmits the optimized dosage to the PLC control system, which then controls the dosing execution device to perform the dosing.

[0055] S4. Detection and Feedback: The industrial control computer compares the H2S concentration in the water quality dynamic database with the H2S concentration limit value, which is 10ppm. When the H2S concentration is higher than the H2S concentration limit value, the industrial control computer calculates the dosage of the supplementary drug according to the adjustment model and transmits it to the PLC control system. The PLC control system controls the dosing execution device to perform the supplementary drug dosing.

[0056] In this invention, the drug dosing optimization model is preferably based on the drug dosing inhibition model to obtain the relationship between H2S concentration and urea peroxide dosage, and performs optimization iteration with the baseline value of urea peroxide dosage, and solves the minimization objective function through a QP solver;

[0057] The objective function is preferably... Among them, [H2S] t The predicted H2S concentration is given in ppm and μ. t ω1 represents the dosage of urea peroxide, in kg / h; ω2 represents the weighting parameter for H2S inhibition and cost savings.

[0058] The preferred drug administration inhibition model is... and Where, μ SRB The specific growth rate of sulfate-reducing bacteria, h -1 μ max,SRB The maximum specific growth rate of sulfate-reducing bacteria, h -1 ;[SO4 2- SO4 in wastewater 2- Concentration, mg / L; Ks is the sulfate half-saturation constant, mg / L; [COD] is the organic matter concentration, mg / L; K COD [H2O2] is the half-saturation constant of the organic compound, in mg / L; [H2O2] is the dosage in μg / L. t The concentration of hydrogen peroxide released by urea peroxide, mg / L; K I，SRB [SRB] represents the drug inhibition constant, in mg / L; [SRB] represents the number of viable SRB cells per unit volume of wastewater, in cells / mL.

[0059] The reference value for the dosage of urea peroxide is preferably based on... Calculate, where C 最佳 1–3 mmol / L; Q in The flow rate of the wastewater is m. 3 / h; This is the ratio of the sulfate concentration in actual wastewater to the sulfate concentration in the experimental baseline, i.e. The experimental baseline sulfate concentration

[0060] In this invention, ω1 is preferably 0.6 to 0.8, more preferably 0.7; ω2 is preferably 0.2 to 0.3, more preferably 0.25; the values ​​of ω1 and ω2 need to take into account the expected hydrogen sulfide suppression effect and dosage cost in different pipeline systems; for example, for urban municipal pipelines, the requirement for hydrogen sulfide suppression effect will be higher, and ω1 will be higher.

[0061] In this invention, the μ max,SRB The preferred value is 0.12 to 0.18 h. -1 More preferably, it is 0.14–0.16 h. -1 Ks is preferably 40–60 mg / L, more preferably 45–55 mg / L, and even more preferably 50 mg / L; K COD Preferably, the concentration is 80–120 mg / L, more preferably 90–110 mg / L, and even more preferably 100 mg / L; [H2O2] is preferably calculated from the baseline value of urea peroxide dosage, with each mole of urea peroxide releasing 1 mol of hydrogen peroxide; K I，SRB Preferably 0.15–0.25 mg / L, more preferably 0.2 mg / L; [SRB] is preferably 10 mg / L. 5 ~10 7 cell / mL.

[0062] In this invention, the adjustment model is preferably... Where, μ PID K represents the dosage of urea peroxide supplementation, in kg / h; e(t) represents the concentration deviation of H2S, in ppm; d K is the differential coefficient, kg / ppm; p K is a proportionality coefficient, expressed in kg / h / ppm. i The integral coefficient is kg / (h) 2 / ppm).

[0063] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0064] Example 1

[0065] The initial wastewater used in this embodiment was municipal wastewater from a wet well on the campus of Tianjin University, which was collected and stored at 4°C.

[0066] The composition of the artificially prepared wastewater used in this embodiment is shown in Table 1.

[0067] Table 1. Composition of artificially prepared wastewater

[0068]

[0069]

[0070] The simulation experiment used a cylindrical reactor (80 mm in diameter, 149 mm in height, and 0.75 L in volume). The reactor was kept in a completely anaerobic environment, and its exterior was wrapped with aluminum foil to prevent light and algae growth. A magnetic stirrer was installed, operating at 200 rpm to ensure uniform mixing of the wastewater and prevent bottom sediment formation. Four stainless steel rods were fixed inside the reactor, with their ends attached to the top and bottom of the cylindrical reactor. A plastic carrier was fixed to the surface of the stainless steel rods. Initially, actual wastewater was fed to provide actual pipeline microorganisms. During the cultivation process, the microorganisms in the wastewater accumulated and gradually formed a biofilm on the surface of the plastic carrier, simulating the biofilm in actual pipeline wastewater. The total biofilm area to reactor volume ratio was 67 m². 2 / m 3 The experiment simulated the conditions of a small-diameter, high-pressure sewage pipeline. The sewage was heated to 20°C in a water bath before being pumped into the reactor. Each pumping time was 5 minutes.

[0071] 0.75 L of initial wastewater was pumped into a cylindrical reactor using a peristaltic pump. When the generation rates of hydrogen sulfide and methane gases in the reactor reached a steady state (average generation rate of hydrogen sulfide gas was 10.32 mg / (L·h), and the average generation rate of methane gas was 3.24 mg / (L·h)), the wastewater was drained. The reactor was then filled back into the reactor with the initial wastewater using a peristaltic pump, and urea peroxide powder was added for treatment. The molar volume ratio of urea peroxide powder to initial wastewater was 1.8 mmol:1 L. After 6 hours of exposure, the wastewater was drained, and the reactor was filled with artificially prepared wastewater. The concentrations of hydrogen sulfide and methane gases in the reactor were immediately measured, and the generation rates were calculated. The reactor was operated for one month. During this period, the wastewater was drained every 6 hours, and the reactor was refilled with artificially prepared wastewater. The concentrations of hydrogen sulfide and methane gases were measured every two days, and the generation rates were calculated.

[0072] Procedure for determining hydrogen sulfide and methane content: After draining the wastewater and filling it with artificially prepared wastewater within 15 minutes, start timing. Collect gas samples at 0 min, 20 min, 40 min, and 60 min, and measure the concentrations of hydrogen sulfide and methane in the samples. Then, fit a linear relationship between concentration and time to obtain the slope, which is the 1-hour production rate of hydrogen sulfide and methane. The concentration of hydrogen sulfide was determined by the methylene blue method, and the concentration of methane was detected by a gas chromatograph equipped with a flame ionization detector.

[0073] Comparative Example 1

[0074] The initial wastewater, artificially prepared wastewater, and simulation test apparatus used in this comparative example are the same as those in Example 1.

[0075] 0.75L of initial wastewater was pumped into a cylindrical reactor using a peristaltic pump. When the generation rates of hydrogen sulfide and methane gases in the reactor reached a steady state (average generation rate of hydrogen sulfide gas was 10.32 mg / (L·h), and average generation rate of methane gas was 3.24 mg / (L·h)), the wastewater was emptied. Artificially prepared wastewater was then pumped back into the reactor using a peristaltic pump, and the gas concentrations of hydrogen sulfide and methane in the reactor were immediately measured, and the generation rates were calculated. The reactor was operated for one month. During this period, the wastewater was emptied every 6 hours, and the reactor was refilled with artificially prepared wastewater. The gas concentrations of hydrogen sulfide and methane were measured every two days, and the generation rates were calculated.

[0076] The procedure for determining the gas content of hydrogen sulfide and methane is the same as in Example 1.

[0077] Figure 1 C represents the hydrogen sulfide production rate in Example 1 and Comparative Example 1, where C represents Comparative Example 1 and RU represents Example 1. Figure 2 The values ​​represent the methane production rates in Example 1 and Comparative Example 1, where C represents Comparative Example 1 and RU represents Example 1. Figure 1 , Figure 2 It can be seen that the inhibitory effect of urea peroxide in Example 1 is significantly better than that of Comparative Example 1, which did not undergo chemical dosing.

[0078] Example 2

[0079] An online monitoring system is used to monitor actual wastewater and collect data to create a dynamic water quality database. This database includes data on wastewater pH, H2S concentration, sulfate concentration, COD, and flow rate.

[0080] Based on the wastewater flow rate and sulfate concentration, through Calculate the baseline dosage of urea peroxide, and then apply the objective function. Optimize the dosage of urea peroxide. The specific steps are as follows:

[0081] (1) Obtain the wastewater flow rate Q from the water quality dynamic database. in sulfate concentration COD and pH value;

[0082] (2) According to The baseline value for calculating the dosage of urea peroxide is given, where C 最佳 The optimal concentration of urea peroxide is 1–3 mmol / L, or 94–282 mg / L; Q in The flow rate of the wastewater is m. 3 / h; This is the ratio of the actual sulfate concentration in wastewater to the experimental baseline sulfate concentration, i.e. The experimental baseline sulfate concentration

[0083] (3) Based on the drug inhibition model

[0084] and The relationship between the predicted H2S concentration and the amount of urea peroxide added was obtained. Wherein, μ SRB h represents the specific growth rate of SRB. -1 μ max,SRB The maximum specific growth rate of sulfate-reducing bacteria, h -1 0.12~0.18h -1 [H2S] represents the concentration of H2S, in ppm; [SO4] represents the concentration of H2S, in ppm. 2- [[COD]] represents sulfate concentration, mg / L; [COD] represents organic matter concentration, mg / L; Ks is the sulfate half-saturation constant, mg / L, 40–60 mg / L; K COD K is the half-saturation constant of organic matter, mg / L, 80–120 mg / L; I，SRB [α] represents the drug inhibition constant, mg / L, 0.15–0.25 mg / L; [SRB] represents the number of viable SRB cells per unit volume of wastewater, cells / mL, 10 5 ~10 7 cell / mL; [H2O2] represents the dosage in μg / mL. t The concentration of hydrogen peroxide released by urea peroxide, mg / L, is determined by μ. 1，base Calculations show that each mole of urea peroxide releases 1 mol of hydrogen peroxide.

[0085] (4) Optimize iteratively using the baseline value of urea peroxide dosage, and solve the minimization objective function using a QP solver. The optimal dosage of urea peroxide was obtained, wherein [H2S] t The predicted H2S concentration is given in ppm and μ. t ω1 represents the dosage of urea peroxide, in kg / h; ω2 represents the weighting parameter for H2S inhibition, in the range of 0.6 to 0.8; and ω3 represents the weighting parameter for cost savings, in the range of 0.2 to 0.3.

[0086] (5) The industrial control computer transmits the optimized dosage of urea peroxide to the PLC control system, and the PLC control system controls the dosing device to perform the dosing.

[0087] (6) When the H2S concentration is shown to be >10 ppm in the water quality dynamic database, the dosage of urea peroxide is calculated according to the adjustment model, and the dosage is then supplemented. The adjustment model is... Where, μ PID K represents the dosage of urea peroxide, in kg / h; e(t) represents the concentration deviation of H2S, i.e., the difference between the H2S concentration limit (10ppm) and the measured value, in ppm; Kp K is a proportionality coefficient, expressed in kg / h / ppm. i The integral coefficient is kg / (h) 2 / ppm); K d The coefficient is the differential value, expressed in kg / ppm. By adjusting the model, the H2S concentration can be reduced to a safe range in a timely manner, avoiding over-dosing.

[0088] K d K p K i The adjustment plan is as follows: First, set K i =0,K d =0, artificially caused H2S to exceed the standard by 5ppm, K is gradually increased from 0. p The system continues to oscillate (i.e., the system oscillates in the adjustment model, with the H2S concentration near the H2S concentration limit and the H2S concentration deviation fluctuating between positive and negative) until the critical value K is reached. u Take K p =0.5K u For example, when K u When K = 1.2, the system oscillates, then K p =0.5×

[0089] 1.2 = 0.6 kg / h / ppm; K i =K p / T i After adding 2 times the amount of urea peroxide, record the time it takes for H2S to go from exceeding the standard to reaching the standard. i = 1.2 × measured time, for example, if the time for H2S to go from exceeding the standard to reaching the standard is 15 minutes, then T i =18min; K d =T i ×K p ×0.5.

[0090] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A smart method for controlling hydrogen sulfide and methane in sewage pipe networks by activating urea peroxide, characterized in that, It includes the following steps: Urea peroxide is added to the sewage pipe network to treat the sewage; Adding urea peroxide to the sewage pipe network also includes quantitative control of the dosage through a smart system; The intelligent system includes an online monitoring device, a drug delivery device, and a control center; The online monitoring device monitors the wastewater online to obtain a dynamic water quality database; the dynamic water quality database includes pH value, H2S concentration, sulfate concentration, COD, and flow rate; The dosing device includes a storage tank, a dosing pipeline, and a dosing port. The storage tank is connected to the dosing port via the dosing pipeline. The dosing pipeline is equipped with a dosing metering pump, an electric valve, and a detector. The control center includes an industrial computer and a PLC control system. The dosing metering pump, electric valve, detector, and online monitoring device are respectively connected to the industrial computer, and the industrial computer is connected to the PLC control system. The process of quantitative drug administration controlled by the intelligent system includes the following steps: S1. Water quality dynamic database acquisition: Collects the pH value, H2S concentration, sulfate concentration, COD and flow rate of wastewater through online monitoring devices and transmits them to the industrial control computer; S2. Model Calculation: The industrial control computer uses the water quality dynamic database to perform a dosing optimization model to obtain the optimized dosing amount and predicted H2S concentration. S3. Dosing execution: The industrial control computer transmits the optimized dosage to the PLC control system, which then controls the dosing execution device to perform the dosing. S4. Detection and Feedback: The industrial control computer compares the H2S concentration in the water quality dynamic database with the H2S concentration limit value, which is 10 ppm. When the H2S concentration is higher than the H2S concentration limit value, the industrial control computer calculates the dosage of the chemical supplementation based on the adjustment model and transmits it to the PLC control system. The PLC control system controls the chemical dosing execution device to perform the chemical supplementation. The drug dosing optimization model is based on the drug dosing inhibition model to obtain the relationship between H2S concentration and urea peroxide dosage, and performs optimization iterations with the baseline value of urea peroxide dosage, and solves the minimization objective function through a QP solver; The objective function is: Among them, [H2S] t The predicted H2S concentration is given in ppm and μ. t ω1 represents the dosage of urea peroxide, in kg / h; ω2 represents the weighting parameter for H2S inhibition and cost savings. The drug administration inhibition model is: and , where μ SRB The specific growth rate of sulfate-reducing bacteria, h -1 μ max,SRB The maximum specific growth rate of sulfate-reducing bacteria, h -1 ;[SO4 2- SO4 in wastewater 2- Concentration, mg / L; Ks is the sulfate half-saturation constant, mg / L; [COD] is the organic matter concentration, mg / L; K COD [H2O2] is the half-saturation constant of the organic compound, in mg / L; [H2O2] is the dosage in μg / L. t The concentration of hydrogen peroxide released by urea peroxide, mg / L; K I，SRB [SRB] represents the drug inhibition constant, in mg / L; [SRB] represents the number of viable SRB cells per unit volume of wastewater, in cells / mL. The baseline value for the urea peroxide dosage is based on Calculate, where C 最佳 1~3mmol / L; Q in The flow rate of the wastewater is m. 3 / h; This is the ratio of the sulfate concentration in actual wastewater to the sulfate concentration in the experimental baseline, i.e. The experimental baseline sulfate concentration =30mg / L; The adjustment model is as follows: , where μ PID The dosage of urea peroxide is given in kg / h; e(t) is the concentration deviation of H2S in ppm. K d These are the differential coefficients; K p This is the proportionality coefficient; K i is the integral coefficient.

2. The method according to claim 1, characterized in that, It also includes adding activators to the sewage pipe network.

3. The method according to claim 2, characterized in that, The activator is a substance that can activate urea peroxide to generate hydroxyl radicals, superoxide radicals, and singlet oxygen.

4. The method according to claim 3, characterized in that, The molar volume ratio of the urea peroxide dosage to the wastewater is 1~3 mmol:1L.

5. The method according to claim 2 or 3, characterized in that, The molar volume ratio of the activator to the wastewater is 0.1~0.3 mmol:1L.

6. The method according to claim 5, characterized in that, The processing time is 5-8 hours.

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