Sewage disinfection system and precise regulation and control method

Abstract

The invention relates to a sewage disinfection system which comprises a sewage disinfection reaction unit, a first monitoring subunit, a disinfectant adding subunit, a second monitoring subunit and a disinfectant control subunit, the first monitoring subunit, the disinfectant adding subunit and the second monitoring subunit are all connected with the sewage disinfection reaction unit and the disinfectant control subunit; and one output end of the disinfectant control subunit is communicated with one input end of the disinfectant adding subunit. The regulation and control system has the beneficial effects that the regulation and control system is simple in composition and convenient to operate, and monitored signals are transmitted to the disinfectant control subunit through the first monitoring subunit, the disinfectant adding subunit and the second monitoring subunit so as to regulate and control the disinfectant adding subunit to disinfect sewage in the sewage disinfection reaction unit; the sewage disinfection effect is indicated through the effluent ORP value, the water quality stability of the sewage disinfection effluent is improved, and the ecological safety of the effluent is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a sewage disinfection system and a precise control method. Background Art

[0002] The influent of urban sewage treatment plants contains a large number of pathogens such as microorganisms, bacteria, and viruses. If undisinfected sewage is directly discharged into the water body, the pathogens will spread through different pathways and cause health risks. Therefore, the disinfection process unit in sewage treatment is crucial. At present, the main disinfection method used by urban sewage treatment plants in my country is chlorine disinfection.

[0003] However, the operation and control of the disinfection process unit of urban sewage treatment plants still face a series of problems: ① There is a lag in using the number of fecal coliform bacteria as a control indicator for the disinfection effect. The multi-tube fermentation method is used to detect the number of fecal coliform bacteria, and the detection time is 48 hours, which cannot judge the disinfection effect of the effluent in real time. When natural disasters or public health events occur, pathogens in the sewage system increase significantly, and this detection method cannot ensure that the number of fecal coliform bacteria in the effluent is stable and meets the standard. ② The addition of chlorine disinfectant has not been precisely regulated. At present, the amount of chlorine disinfectant added to the disinfection unit of the sewage treatment plant is regulated according to the experience of the operating personnel, and the survey shows that sewage plants often over-add chlorine disinfectants to ensure that the number of fecal coliform bacteria in the effluent meets the standard, and it is impossible to achieve accurate addition and dynamic adjustment of chlorine disinfectants. ③ Excessive chlorine disinfectants will affect the ecological safety of the receiving water body. my country's current "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB18918-2002) and local standards for urban sewage treatment plants in various places do not stipulate the limit value of residual chlorine discharged by sewage treatment plants. Studies have shown that excessive residual chlorine will also have a certain toxic effect on aquatic organisms. ④ Excessive chlorine disinfectant will generate chlorine disinfection by-products. During the chlorine disinfection process, chlorine reacts with organic matter in sewage to generate by-products such as trihalomethanes (THMs) and haloacetic acids (HAAs). These substances are carcinogenic and mutagenic, posing a long-term threat to human health. Especially in sewage with high organic content, the amount of by-products generated increases, increasing the risk of water pollution and affecting environmental safety.

[0004] Therefore, there is an urgent need for a control system that can determine in real time whether the fecal coliform count and residual chlorine index in the effluent meet the standards, and can provide real-time feedback to control the amount of chlorine disinfectant added at the front end, to ensure that the fecal coliform count and residual chlorine in the effluent meet the standards, and to accurately control the amount of chlorine disinfectant added. Summary of the invention

[0005] The present invention aims at solving the technical problems existing in the prior art and provides a sewage disinfection system and method.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: A first aspect of protection, a sewage disinfection system, includes a sewage disinfection reaction unit, a first monitoring subunit, a disinfectant dosing subunit, a second monitoring subunit, and a disinfectant control subunit; The first monitoring subunit, the disinfectant dosing subunit, and the second monitoring subunit are all connected to the sewage disinfection reaction unit and the disinfectant control subunit. The first monitoring subunit is used to monitor the water inlet flow of the sewage disinfection reaction unit in real time, the disinfectant dosing subunit is used to add disinfectant to the sewage disinfection reaction unit, and the second monitoring subunit is used to monitor the redox potential value of the effluent in the sewage disinfection reaction unit in real time. An output end of the disinfectant control subunit is connected to an input end of the disinfectant dosing subunit to collect data from the first monitoring subunit, the disinfectant dosing subunit, and the second monitoring subunit to adjust the dosage of the disinfectant dosing subunit.

[0007] As a further technical solution, the first monitoring subunit includes a flow meter and a first sensor arranged on the flow meter, and the flow meter is arranged on the water inlet pipe of the sewage disinfection reaction unit.

[0008] As a further technical solution, the disinfectant dosing subunit includes a metering pump and a disinfectant storage tank connected to the input end of the metering pump, a second sensor, and a controller. The metering pump is connected to the disinfection reaction tank in the sewage disinfection reaction unit.

[0009] As a further technical solution, the second monitoring subunit includes an oxidation-reduction potential meter and a third sensor arranged on the oxidation-reduction potential meter, and the oxidation-reduction potential meter is arranged on the outlet channel in the sewage disinfection reaction unit.

[0010] As a further technical solution, the disinfectant control subunit includes an input module, a central processing unit, a memory, and an output module, an output end of the input module is connected to an input end of the central processing unit, an output end of the central processing unit is connected to the output unit, and the central processing unit is connected to the memory to realize bidirectional transmission of data signals; The first sensor, the second sensor, and the third sensor are all connected to the input end of the input module, and an output end of the output module is connected to the controller to control the flow rate of the metering pump.

[0011] As a further technical solution, a central remote control unit is also included, which is connected to the disinfectant control subunit and realizes two-way transmission of data signals.

[0012] The second aspect of the present invention is to protect a precise control method of a sewage disinfection system, comprising the system as described in the first aspect, and the specific steps are as follows: S1. The test data of effective chlorine dosage, effluent ORP (oxidation-reduction potential), effluent fecal coliform count and effluent residual chlorine value are obtained through the chlorine disinfectant addition test and are kept for future use; S2, by nonlinear surface data fitting, obtain the quantitative relationship model 1 of effective chlorine dosage for sewage disinfection-outlet ORP-outlet fecal coliform group number, and by polynomial fitting analysis, obtain the quantitative relationship model 2 of disinfection effluent ORP-residual chlorine; and preset the target value of the number of fecal coliform group in the disinfection effluent, the target value of residual chlorine, the effective chlorine concentration of the chlorine disinfectant, the calculation model of effective chlorine dosage, the quantitative relationship model 1, and the quantitative relationship model 2 in the disinfectant control subunit; S3, the disinfectant control subunit calculates the real-time effective chlorine dosage, the number of fecal coliform bacteria in the effluent and the effluent residual chlorine according to the data signals transmitted in real time by the first monitoring subunit, the disinfectant dosing subunit and the second monitoring subunit and the model preset in the disinfectant control subunit in step S2; S4, comparing the calculation result of step S3 with the target value preset in the disinfectant control subunit, and sending a control instruction to the disinfectant dosing subunit according to the comparison result; Among them, the preset target values ​​in the disinfectant control subunit are the target value of fecal coliform count in the disinfected effluent, the target value of residual chlorine, and the effective chlorine concentration of the chlorine disinfectant.

[0013] As a further technical solution, in step S2, the quantitative relationship model 1 is:

[0014] in: is the number of fecal coliform bacteria in the effluent (pieces / L), is the effective chlorine dosage (mg / L), is the redox potential (mV), , , , , , is the fitting parameter; Quantitative relationship model 2 is:

[0015] in: is the residual chlorine value of the effluent (mg / L), is the redox potential (mV), , , is the fitting parameter; The calculation model of effective chlorine dosage is: , in, is the effective chlorine dosage (mg / L), Q 1 is the water inlet flow rate value of the sewage disinfection reaction unit (m 3 / h), Q 2 is the flow rate of disinfectant added by the disinfectant dosing subunit (m 3 / h), k is the effective chlorine concentration (mg / L).

[0016] As a further technical solution, step S3 includes the following steps: S31, the first monitoring subunit and the disinfectant dosing subunit monitor Q in real time respectively 1 , Q 2 and will monitor the Q 1 , Q 2 The data signal is transmitted to the disinfectant control subunit to calculate the real-time effective chlorine dosage of the disinfectant dosing subunit. value; S32, the disinfectant control subunit monitors the outlet water ORP in real time according to the second monitoring subunit, the The real-time fecal coliform count in effluent is calculated by using the value and the preset quantitative relationship model 1; The disinfectant control subunit calculates the real-time residual chlorine in the effluent water according to the ORP monitored in real time by the second monitoring subunit and the preset quantitative relationship model 2.

[0017] As a further technical solution, in step S4, specifically: The disinfectant control subunit compares the calculated real-time effluent fecal coliform count and real-time effluent residual chlorine with the target value preset in step S2: If the real-time effluent fecal coliform count is less than the target fecal coliform count, and the real-time effluent residual chlorine value is less than the target residual chlorine value, the discharge standard is met, and the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to maintain the current effective chlorine dosage; If the real-time effluent fecal coliform count is less than the target value of fecal coliform count, but the real-time effluent residual chlorine value is greater than or equal to the target value of residual chlorine, the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to gradually reduce the dosage of chlorine disinfectant until the effluent ORP value feedback shows that the real-time residual chlorine is less than the target value of residual chlorine, that is, the effective chlorine dosage is maintained; If the real-time fecal coliform count in the effluent is ≥ the target fecal coliform count, the disinfectant control subunit calculates the corresponding effective chlorine dosage according to the real-time ORP value, the target fecal coliform count and the preset quantitative relationship model 1. , and then according to Q 1 The calculation model of effective chlorine dosage is used to calculate Q2 ; The disinfectant control subunit sends a command to the disinfectant dosing subunit, immediately adjusting the chlorine disinfectant dosing flow value to the calculated Q 2 , and continuously monitor the effluent ORP value until the effluent ORP value feedback shows that the real-time effluent fecal coliform count is less than the target fecal coliform count, and the residual chlorine value is less than the target residual chlorine value, that is, maintain the effective chlorine dosage.

[0018] The beneficial effects of the present invention are: 1. The control system of the present invention has a simple composition and is easy to operate. The monitoring signal is transmitted to the disinfectant control subunit through the first monitoring subunit, the disinfectant dosing subunit and the second monitoring subunit, so as to control the disinfectant dosing subunit to disinfect the sewage in the sewage disinfection reaction unit. By controlling the dosage of the disinfectant, the consumption of the disinfectant and the operating cost of the disinfection process unit are effectively reduced, so as to help the sewage treatment plant achieve energy saving and carbon reduction green operation; the sewage disinfection effect is indicated by the effluent ORP value, which is equivalent to replacing the fecal coliform group number and residual chlorine index, thereby improving the stability of the effluent water quality of the sewage disinfection effluent and ensuring the ecological safety of the effluent; 2. The control method of the present invention is based on the ORP equivalent principle. The effluent ORP is monitored by the second monitoring subunit. The quantitative relationship model 1 and the quantitative relationship model 2 are preset in the disinfectant control subunit to achieve equivalent and accurate calculation of the fecal coliform group count and the residual chlorine value of the disinfected effluent. This solves the hysteresis problem of conventional fecal coliform group detection, achieves real-time monitoring of the effluent residual chlorine value, and ensures that the fecal coliform group count and the residual chlorine value of the effluent from sewage disinfection meet the standards. 3. The control method of the present invention simplifies the operation and maintenance workflow of the sewage treatment plant, improves the intelligent operation and management of the sewage treatment plant, and realizes the digitization and intelligence of the sewage disinfection process unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A connection structure block diagram of a sewage disinfection system of the present invention; Figure 2 is a structural block diagram of the first monitoring subunit of the present invention; Figure 3 It is a structural block diagram of the disinfectant dosing subunit of the present invention; Figure 4 is a structural block diagram of the second monitoring subunit of the present invention; Figure 5 is a structural block diagram of the disinfectant control subunit of the present invention; Figure 6 It is a structural block diagram of the central remote control unit of the present invention; Figure 7 The quantitative relationship model 1 in Embodiment 2 of the present invention; Figure 8This is the quantitative relationship model 2 in Example 2 of the present invention.

[0020] In the accompanying drawings, the components represented by the reference numerals are listed as follows: Sewage disinfection reaction unit 10, water inlet pipe 11, disinfection reaction tank 12, outlet channel 13; A first monitoring subunit 20, a flow meter 21, and a first sensor 22; Disinfectant dosing subunit 30, metering pump 31, disinfectant storage tank 32, second sensor 33, controller 34; A second monitoring subunit 40, an oxidation-reduction potential meter 41, and a third sensor 42; Disinfectant control subunit 50, input module 51, central processing unit 52, memory 53, output module 54; Central remote control unit 60 , data server 61 , application server 62 , security protection gateway 63 . DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0022] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0023] In the description of the present application, the term "for example" is used to mean "used as an example, illustration or description". Any embodiment described as "for example" in the present application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any technician in the field to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes will not be elaborated in detail to avoid unnecessary details to obscure the description of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in the present application.

[0024] Example 1 In order to effectively treat sewage, for example, to disinfect sewage, the operator can monitor the inlet flow, outlet ORP, and effective chlorine dosage and feed it back to the control system. The operator can then adjust the disinfectant dosage based on the judgment to achieve disinfectant dosage control. Figure 1 , this embodiment provides a sewage disinfection system, including a sewage disinfection reaction unit 10, a first monitoring subunit 20, a disinfectant dosing subunit 30, a second monitoring subunit 40, a disinfectant control subunit 50, and a central remote control unit 60; The first monitoring subunit 20, the disinfectant dosing subunit 30, and the second monitoring subunit 40 are all connected to the sewage disinfection reaction unit 10 and the disinfectant control subunit 50. The first monitoring subunit 20 is used to monitor the water inlet flow rate of the sewage disinfection reaction unit 10 in real time, the disinfectant dosing subunit 30 is used to add disinfectant to the sewage disinfection reaction unit 10, and the second monitoring subunit 40 is used to monitor the redox potential value of the effluent in the sewage disinfection reaction unit 10 in real time; at the same time, the first monitoring subunit 20 feeds back the real-time monitored water inlet flow rate value to the disinfectant control subunit 50; An output end of the disinfectant control subunit 50 is connected to an input end of the disinfectant dosing subunit 30, so as to collect data from the first monitoring subunit 20, the disinfectant dosing subunit 30, and the second monitoring subunit 40 and then adjust the dosage of the disinfectant dosing subunit 30; The central remote control unit 60 is connected to the disinfectant control subunit 50 and realizes two-way transmission of data signals.

[0025] It can be explained that the disinfectant in this embodiment can be a chlorine disinfectant; the sewage disinfection reaction unit 10 is used for the disinfection contact reaction process of sewage.

[0026] In the specific implementation process, see Figure 2 The first monitoring subunit 20 includes a flow meter 21 and a first sensor 22 arranged on the flow meter 21. The flow meter 21 is arranged on the water inlet pipe 11 of the sewage disinfection reaction unit 10 to monitor the flow rate of sewage entering the sewage disinfection reaction unit 10 in real time, and the first sensor 22 is used to read the data of the flow meter 21 in real time and transmit the read data to the disinfectant control subunit 50.

[0027] In the specific implementation process, see Figure 3The disinfectant dosing subunit 30 includes a metering pump 31 and a disinfectant storage tank 32 connected to the input end of the metering pump 31, a second sensor 33, and a controller 34. The metering pump 31 is connected to the disinfection reaction tank 12 in the sewage disinfection reaction unit 10 to add disinfectant, such as chlorine disinfectant, into the sewage disinfection reaction unit 10; the second sensor 33 and the controller 34 are both arranged on the metering pump 31, and the flow data of the metering pump 31 is monitored in real time by the second sensor 33, and the controller 34 is used to adjust and control the working state and parameters of the metering pump 31, that is, to control the flow rate of the metering pump 31.

[0028] In the specific implementation process, see Figure 4 The second monitoring subunit 40 includes an oxidation-reduction potential meter 41 and a third sensor 42 arranged on the oxidation-reduction potential meter 41. The oxidation-reduction potential meter 41 is arranged on the outlet channel 13 in the sewage disinfection reaction unit 10 to monitor the oxidation-reduction potential value of the effluent after disinfection in real time; and the third sensor 42 is used to read the data of the oxidation-reduction potential meter 41 in real time and transmit the data to the disinfectant control subunit 50.

[0029] In the specific implementation process, see Figure 5 The disinfectant control subunit 50 includes an input module 51, a central processing unit 52, a memory 53, and an output module 54. An output end of the input module 51 is connected to an input end of the central processing unit 52, and an output end of the central processing unit 52 is connected to the output module 54. The central processing unit 52 is connected to the memory 53 and realizes bidirectional transmission of data signals; the first sensor 22, the second flow meter 21, and the third sensor 42 are all connected to the input end of the input module 51, and an output end of the output module 54 is connected to the controller 34 to control the flow rate of the metering pump 31.

[0030] It can be explained that the first sensor 22, the second sensor 33, and the third sensor 42 are all connected to the input module 51. It can be known that the input module 51 is at least used to receive relevant data detected by each sensor; the memory 53 is used to store system programs and user programs, and the central processor 52 compares the data transmitted from the input module 51 according to the program in the memory 53 and transmits corresponding instructions to the output module 54. The output module 54 is connected to the controller 34, and transmits the instructions of the central processor 52 to the metering pump 31, so as to realize the regulation of the disinfectant control subunit 50 on the disinfectant dosing subunit 30.

[0031] In the specific implementation process, see Figure 1 , Figure 6 The central remote control unit 60 includes a data server 61, an application server 62, and a security protection gateway 63. The data server 61 realizes bidirectional transmission of data signals with the application server 62 and the security protection gateway 63; an output end of the output module 54 is signal-connected with an input end of the security protection gateway 63, and the data of the data server 61 is read in real time through the application server 62. The output module 54 transmits the program calculation data, results and instructions of the central processor 52 to the data server 61 for storage. The application server 62 can read real-time data and historical data from the data server 61, and the user can read the data of the first monitoring subunit 20, the disinfectant dosing subunit 30, the second monitoring subunit 40, and the disinfectant control subunit 50 through the application server 62. The user can also send instructions to the disinfectant control subunit 50 through the application server 62 to realize remote control of the disinfectant dosing subunit 30.

[0032] It can be explained that the central remote control unit 50 includes a power supply for providing power to the input module 51 , the central processor 52 , the memory 53 , and the output module 54 .

[0033] It can be explained that, in the present invention: The flow meter 21 may be an ultrasonic flow meter LRF-3000SC or an electromagnetic flow meter ORBLDBE-50-316L-4F; the first sensor 22 may be a KJT-LSA500 flow sensor; The metering pump 31 can be a diaphragm metering pump GM170 or an electromagnetic diaphragm metering pump AKS600; The second sensor 33 may be an ACU10L-L flow sensor; The controller 34 may be a Milton Roy HED1P1C controller or a Pulsfeld NEMA4 controller; The redox potential meter 41 may be a JD-ZS6 redox potential meter or a MIK-MDC redox potential meter; The third sensor 42 may be a Y533-A sensor; The input module 51 can be Siemens EM DE08 or Omron CJ1W-ID261; The central processor 52 may be Siemens CPU SR20 or Omron CJ1M-CPU13-ETN; The memory 53 may be Siemens 6ES7952-1AM00-0AA0 or Omron C200H-ME431; The output module 54 may be Siemens EM DR08 or Omron EM DT08.

[0034] The present invention is achieved in that: Disinfectant can be added into the sewage disinfection reaction unit 10 through the disinfectant adding subunit 30 to disinfect the sewage; The first sensor 22 obtains the flow data of the water inlet pipe 11 measured by the flowmeter 21 in real time, the second sensor 33 obtains the flow data of the metering pump 31 in real time, and the third sensor 42 obtains the water outlet ORP data measured by the oxidation-reduction potential meter 41 in real time. The first sensor 22, the second sensor 33, and the third sensor 42 transmit the acquired data signals to the input module 51 in real time. The water outlet ORP control value (ORP ≥ 650mV) is preset in the memory 53. When the water outlet ORP ≥ 650mV, the effective chlorine dosage is maintained. When the water outlet ORP < 650mV, the central processor 52 sends an instruction to increase the dosage of the metering pump 31 until the water outlet ORP ≥ 650mV. The output module 54 transmits the real-time data signal of the central processor 52 to the data server 61 through the security protection gateway 63. The user can retrieve the real-time data signal through the application server 62, or send instructions to the disinfectant control subunit 50 to realize remote control of the disinfectant dosing subunit 30. That is, by monitoring the sewage inlet flow, effluent ORP, and effective chlorine dosage, and feeding back these values ​​to the disinfectant control subunit 50 to adjust the disinfectant dosage, the disinfectant dosage can be effectively controlled with low cost and good effect.

[0035] Example 2 This embodiment provides a precise control method for a sewage disinfection system. It can be explained that the method includes the system described in Example 1, so as to determine whether the number of fecal coliform bacteria in water and the residual chlorine index meet the standard through the system of Example 1, and to provide real-time feedback and precisely control the amount of chlorine disinfectant added at the front end. The specific steps of the method are as follows: S1. The test data of effective chlorine dosage, effluent ORP value, effluent fecal coliform count and effluent residual chlorine value are obtained through chlorine disinfectant addition test and are reserved for future use; S2, by nonlinear surface data fitting, obtain the quantitative relationship model 1 of effective chlorine dosage for sewage disinfection-outlet ORP-outlet fecal coliform group number, and by polynomial fitting analysis, obtain the quantitative relationship model 2 of disinfection effluent ORP-residual chlorine; and preset the target value of the number of fecal coliform group in the disinfection effluent, the target value of residual chlorine, the effective chlorine concentration of the chlorine disinfectant, the calculation model of effective chlorine dosage, the quantitative relationship model 1, and the quantitative relationship model 2 in the disinfectant control subunit; In this step, the quantitative relationship model 1 is:

[0036] in: is the number of fecal coliform bacteria in the effluent (pieces / L), is the effective chlorine dosage (mg / L), is the redox potential (mV), , , , , , is the fitting parameter; Quantitative relationship model 2 is:

[0037] in: is the residual chlorine value of the effluent (mg / L), is the redox potential (mV), , , is the fitting parameter; The calculation model of effective chlorine dosage is: , in, is the effective chlorine dosage (mg / L), Q 1 is the water inlet flow rate value of the sewage disinfection reaction unit (m 3 / h), Q 2 is the flow rate of disinfectant added by the disinfectant dosing subunit (m 3 / h), k is the effective chlorine concentration (mg / L); S3, the disinfectant control subunit calculates the real-time effective chlorine dosage, the number of fecal coliform bacteria in the effluent and the effluent residual chlorine according to the data signals transmitted in real time by the first monitoring subunit, the disinfectant dosing subunit and the second monitoring subunit and the model preset in the disinfectant control subunit in step S2; This step includes: S31, the first monitoring subunit and the disinfectant adding subunit respectively monitor Q in real time 1 , Q 2 and will monitor the Q 1 , Q 2 The data signal is transmitted to the disinfectant control subunit to calculate the real-time effective chlorine dosage of the disinfectant dosing subunit. value; S32, the disinfectant control subunit monitors the outlet water ORP in real time according to the second monitoring subunit, the The real-time fecal coliform count in effluent is calculated by using the value and the preset quantitative relationship model 1; The disinfectant control subunit calculates the real-time residual chlorine in the effluent water according to the ORP monitored in real time by the second monitoring subunit and the preset quantitative relationship model 2.

[0038] S4, comparing the calculation result of step S3 with the target value preset in the disinfectant control subunit, and sending a control instruction to the disinfectant dosing subunit according to the comparison result; Among them, the preset target values ​​in the disinfectant control subunit are the target value of fecal coliform count in the disinfected effluent, the target value of residual chlorine, and the effective chlorine concentration of the chlorine disinfectant.

[0039] This step is specifically: the disinfectant control subunit compares the calculated real-time effluent fecal coliform count and real-time effluent residual chlorine with the target value preset in step S2: If the real-time effluent fecal coliform count is less than the target fecal coliform count, and the real-time effluent residual chlorine value is less than the target residual chlorine value, the discharge standard is met, and the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to maintain the current effective chlorine dosage; If the real-time effluent fecal coliform count is less than the target value of fecal coliform count, but the real-time effluent residual chlorine value is greater than or equal to the target value of residual chlorine, the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to gradually reduce the dosage of chlorine disinfectant until the effluent ORP value feedback shows that the real-time residual chlorine is less than the target value of residual chlorine, that is, the effective chlorine dosage is maintained; If the real-time fecal coliform count in the effluent is ≥ the target fecal coliform count, the disinfectant control subunit calculates the corresponding effective chlorine dosage according to the real-time ORP value, the target fecal coliform count and the preset quantitative relationship model 1. , and then according to Q 1 The calculation model of effective chlorine dosage is used to calculate Q 2 The disinfectant control subunit sends a command to the disinfectant dosing subunit to immediately adjust the chlorine disinfectant dosing flow rate to the target value Q 2 , and continuously monitor the effluent ORP value until the effluent ORP value feedback shows that the real-time effluent fecal coliform count is less than the target fecal coliform count, and the residual chlorine value is less than the target residual chlorine value, that is, maintain the effective chlorine dosage.

[0040] The following is a chlorine disinfectant addition test on the disinfection inlet water sample of a sewage treatment plant to obtain the quantitative relationship model 1 and quantitative relationship model 2 of the sewage treatment plant; A certain amount of chlorine disinfectant was added to the disinfection inlet water sample (effective chlorine dosage gradient: 1.0, 2.0, 3.0, 4.0, 5.0 mg / L). After a certain period of reaction at room temperature of 25°C (such as time gradient: 0, 5, 10, 20, 30 min), samples were taken to determine the redox potential ORP, fecal coliform count and residual chlorine value, as shown in Table 1 below.

[0041]

[0042] The effective chlorine dosage, redox potential, and fecal coliform count in the chlorine disinfectant dosage experiment data were subjected to nonlinear surface fitting analysis, and a Poly2D function was established, with x being the effective chlorine dosage (mg / L) and y being the redox potential (mV). is the number of fecal coliform bacteria (individuals / L), and the number of fitted fecal coliform bacteria The amount of effective chlorine added and redox potential Quantitative relationship model =f (x, y), the fitting function is as follows:

[0043] Fecal coliform count The quantitative relationship model between the effective chlorine dosage x and the redox potential y is as follows: Figure 7 shown.

[0044] The effluent redox potential and effluent residual chlorine content in the chlorine disinfectant addition experiment data were subjected to polynomial fitting analysis. is the residual chlorine value of the effluent (mg / L), is the redox potential (mV), establish the residual chlorine Redox potential Quantitative relationship model =f(y), as follows:

[0045] Residual Chlorine Redox potential Quantitative relationship model =f (y) Figure 8 shown.

[0046] In the actual operation process, the disinfection water flow rate is set to Q 1 (m 3 / h), the flow rate of the chlorine disinfection dosing pump is Q 2 (m 3 / h), a sewage treatment plant uses chlorine disinfectant as sodium hypochlorite solution with an effective chlorine content of 10% (i.e., an effective chlorine concentration of 10 5 mg / L), effective chlorine dosage of chlorine disinfectant dosing system The calculation model of x=f(Q 1 , Q 2 )as follows:

[0047] Sewage treatment plant A implements the Class A emission standard of the "Pollutant Emission Standard for Urban Sewage Treatment Plants" (GB18918-2002), and the fecal coliform count in the effluent must be less than 1000 / L. In order to ensure that the disinfected effluent does not affect the ecological safety of the water body after being discharged into the environmental water body, the residual chlorine value of the disinfected effluent is limited to less than 0.2mg / L. In order to control the fecal coliform count and residual chlorine in the disinfected effluent and not exceed the standard, the target value of the fecal coliform count in the effluent is preset in the storage device to be ≤900 / L, the target value of the effluent residual chlorine is ≤0.2mg / L, and the priority of the target value of the fecal coliform count in the effluent is higher than the target value of the effluent residual chlorine. Quantitative relationship model 1, quantitative relationship model 2 and effective chlorine dosage calculation model are preset in the storage device.

[0048] The disinfectant control subunit obtains the disinfection water flow value Q in real time 1 , metering pump flow Q 2 The central processor calculates the current effective chlorine dosage according to the data signal and the preset calculation model. The disinfectant control subunit obtains the disinfection effluent ORP data in real time, and calculates the real-time fecal coliform count and residual chlorine value through the preset quantitative relationship model 1 and quantitative relationship model 2. The central processor compares the calculated real-time effluent fecal coliform count and residual chlorine with the preset target value.

[0049] When the real-time fecal coliform count is ≤900 / L, the residual chlorine value is continued to be compared. If the residual chlorine value is ≤0.2mg / L, the disinfectant control subunit sends a command to the disinfectant dosing subunit to keep the current effective chlorine dosage and continue to operate. If the residual chlorine value is greater than 0.2mg / L, the disinfectant control subunit sends a command to the disinfectant dosing subunit to reduce the metering pump flow and the effective chlorine dosage until the real-time residual chlorine value is ≤0.2mg / L.

[0050] When the real-time fecal coliform count is greater than 900 / L, the disinfectant control subunit calculates the corresponding effective chlorine dosage according to the quantitative relationship model 1, the real-time ORP value and the fecal coliform count = 900 / L, and sends an instruction to the disinfectant dosing subunit to immediately increase the metering pump flow, increase the chlorine disinfectant dosage to the target value, and continuously monitor the effluent ORP to calculate the real-time fecal coliform count and the real-time residual chlorine value until the effluent ORP feedback shows that the real-time effluent fecal coliform count is ≤900 / L and the residual chlorine value is ≤0.2 mg / L, that is, the current effective chlorine dosage is maintained; the disinfectant control subunit sends a dynamic adjustment instruction to the disinfectant dosing subunit according to the comparison result to ensure that the fecal coliform count of the disinfected effluent is stably lower than 900 / L and the residual chlorine value is lower than 0.2 mg / L, thereby realizing the equivalent calculation of the fecal coliform count and the residual chlorine value of the disinfected effluent and the precise regulation of the chlorine disinfectant dosage.

[0051] The disinfectant control subunit will disinfect the real-time flow rate Q of the water inlet 1 , metering pump real-time flow Q 2 , ORP value of disinfected effluent, and calculated real-time effective chlorine dosage x, real-time fecal coliform count and residual chlorine value are transmitted to the central remote control unit. The operator can view the operating parameters of the first monitoring subunit in real time through the central remote control unit to ensure the stable operation of the system, and can also send instructions to the disinfectant control subunit through the central remote control unit to manually adjust the flow of the metering pump and modify the stored preset calculation model and target value.

[0052] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0053] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0054] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A sewage disinfection system, characterized in that: It comprises a sewage disinfection reaction unit (10), a first monitoring subunit (20), a disinfectant dosing subunit (30), a second monitoring subunit (40), and a disinfectant control subunit (50); The first monitoring subunit (20), the disinfectant dosing subunit (30), and the second monitoring subunit (40) are all connected to the sewage disinfection reaction unit (10) and the disinfectant control subunit (50); the first monitoring subunit (20) is used to monitor the water inlet flow of the sewage disinfection reaction unit (10) in real time; the disinfectant dosing subunit (30) is used to add disinfectant to the sewage disinfection reaction unit (10); and the second monitoring subunit (40) is used to monitor the redox potential value of the effluent from the sewage disinfection reaction unit (10) in real time; An output end of the disinfectant control subunit (50) is connected to an input end of the disinfectant dosing subunit (30) so as to collect data from the first monitoring subunit (20), the disinfectant dosing subunit (30) and the second monitoring subunit (40) and then adjust the dosage of the disinfectant dosing subunit (30).

2. A sewage disinfection system according to claim 1, characterized in that: The first monitoring subunit (20) comprises a flow meter (21) and a first sensor (22) arranged on the flow meter (21); the flow meter (21) is arranged on the water inlet pipe (11) of the sewage disinfection reaction unit (10).

3. A sewage disinfection system according to claim 2, characterized in that: The disinfectant dosing subunit (30) comprises a metering pump (31), a disinfectant storage tank (32) connected to an input end of the metering pump (31), a second sensor (33), and a controller (34); the metering pump (31) is connected to a disinfection reaction tank (12) in the sewage disinfection reaction unit (10).

4. A sewage disinfection system according to claim 3, characterized in that: The second monitoring subunit (40) comprises an oxidation-reduction potential meter (41) and a third sensor (42) arranged on the oxidation-reduction potential meter (41); the oxidation-reduction potential meter (41) is arranged on the outlet channel (13) in the sewage disinfection reaction unit (10).

5. A sewage disinfection system according to claim 4, characterized in that: The disinfectant control subunit (50) comprises an input module (51), a central processing unit (52), a memory (53), and an output module (54); an output end of the input module (51) is connected to an input end of the central processing unit (52); an output end of the central processing unit (52) is connected to the output module (54); the central processing unit (52) is connected to the memory (53) to realize bidirectional transmission of data signals; The first sensor (22), the second sensor (33), and the third sensor (42) are all connected to an input end of the input module (51), and an output end of the output module (54) is connected to the controller (34) for controlling the flow rate of the metering pump (31).

6. A sewage disinfection system according to claim 5, characterized in that: It also comprises a central remote control unit (60), wherein the central remote control unit (60) is connected to the disinfectant control subunit (50) and realizes bidirectional transmission of data signals.

7. A precise control method for a sewage disinfection system, characterized in that: comprising a system as claimed in any one of claims 1 to 6, The specific steps are as follows: S1. The test data of effective chlorine dosage, effluent ORP value, effluent fecal coliform count and effluent residual chlorine value are obtained through chlorine disinfectant addition test and are reserved for future use; S2, by nonlinear surface data fitting, obtain the quantitative relationship model 1 of effective chlorine dosage for sewage disinfection-outlet ORP-outlet fecal coliform group number, and by polynomial fitting analysis, obtain the quantitative relationship model 2 of disinfection effluent ORP-residual chlorine; and preset the target value of the number of fecal coliform group in the disinfection effluent, the target value of residual chlorine, the effective chlorine concentration of the chlorine disinfectant, the calculation model of effective chlorine dosage, the quantitative relationship model 1, and the quantitative relationship model 2 in the disinfectant control subunit; S3, the disinfectant control subunit calculates the real-time effective chlorine dosage, the number of fecal coliform bacteria in the effluent and the effluent residual chlorine according to the data signals transmitted in real time by the first monitoring subunit, the disinfectant dosing subunit and the second monitoring subunit and the model preset in the disinfectant control subunit in step S2; S4, comparing the calculation result of step S3 with the target value preset in the disinfectant control subunit, and sending a control instruction to the disinfectant dosing subunit according to the comparison result; Among them, the preset target values ​​in the disinfectant control subunit are the target value of fecal coliform count in the disinfected effluent, the target value of residual chlorine, and the effective chlorine concentration of the chlorine disinfectant.

8. The method according to claim 7, characterized in that In step S2, the quantitative relationship model 1 is: in: is the number of fecal coliform bacteria in the effluent (pieces / L), is the effective chlorine dosage (mg / L), is the redox potential (mV), , , , , , is the fitting parameter; Quantitative relationship model 2 is: in: is the residual chlorine value of the effluent (mg / L), is the redox potential (mV), , , is the fitting parameter; The calculation model of effective chlorine dosage is: , in, is the effective chlorine dosage (mg / L), Q1 is the water inlet flow rate of the sewage disinfection reaction unit (m 3 / h), Q2 is the flow rate of disinfectant added by the disinfectant dosing subunit (m 3 / h), k is the effective chlorine concentration (mg / L).

9. The method according to claim 8, characterized in that Step S3 includes the following steps: S31, the first monitoring subunit and the disinfectant dosing subunit monitor Q1 and Q2 in real time respectively, and transmit the monitored Q1 and Q2 data signals to the disinfectant control subunit to calculate the real-time effective chlorine dosage of the disinfectant dosing subunit value; S32, the disinfectant control subunit monitors the outlet water ORP in real time according to the second monitoring subunit, the The real-time fecal coliform count in effluent is calculated by using the value and the preset quantitative relationship model 1; The disinfectant control subunit calculates the real-time residual chlorine in the effluent water according to the ORP monitored in real time by the second monitoring subunit and the preset quantitative relationship model 2.

10. The method according to claim 9, characterized in that In step S4, specifically: The disinfectant control subunit compares the calculated real-time effluent fecal coliform count and real-time effluent residual chlorine with the target value preset in step S2: If the real-time effluent fecal coliform count is less than the target fecal coliform count, and the real-time effluent residual chlorine value is less than the target residual chlorine value, the discharge standard is met, and the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to maintain the current effective chlorine dosage; If the real-time effluent fecal coliform count is less than the target value of fecal coliform count, but the real-time effluent residual chlorine value is greater than or equal to the target value of residual chlorine, the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to gradually reduce the dosage of chlorine disinfectant until the effluent ORP value feedback shows that the real-time residual chlorine is less than the target value of residual chlorine, that is, the effective chlorine dosage is maintained; If the real-time fecal coliform count in the effluent is ≥ the target fecal coliform count, the disinfectant control subunit calculates the corresponding effective chlorine dosage according to the real-time ORP value, the target fecal coliform count and the preset quantitative relationship model 1. , and then calculate Q2 based on Q1 and the calculation model of effective chlorine dosage; The disinfectant control subunit sends an instruction to the disinfectant dosing subunit, immediately adjusts the chlorine disinfectant addition flow value to the calculated Q2, and continuously monitors the effluent ORP value until the effluent ORP value feedback shows that the real-time effluent fecal coliform count is less than the target fecal coliform count, and the residual chlorine value is less than the target residual chlorine value, that is, the effective chlorine dosage is maintained.

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