Sewage disinfection system and precise control method

Abstract

The present application relates to a sewage disinfection system, comprising a sewage disinfection reaction unit, a first monitoring subunit, a disinfectant adding subunit, a second monitoring subunit, a disinfectant control subunit; the first monitoring subunit, the disinfectant adding subunit, the second monitoring subunit are connected with the sewage disinfection reaction unit and the disinfectant control subunit; an output end of the disinfectant control subunit is communicated with an input end of the disinfectant adding subunit. Its beneficial effect is: the regulation and control system is simple in composition and convenient to operate, the signals monitored by the first monitoring subunit, the disinfectant adding subunit and the second monitoring subunit are transmitted to the disinfectant control subunit to regulate and control the disinfectant adding subunit to disinfect the sewage in the sewage disinfection reaction unit; the sewage disinfection effect is indicated by the effluent ORP value, the sewage disinfection effluent water quality stability is improved, and the effluent ecological safety is ensured.

Description

TECHNICAL FIELD

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

[0002] The influent of the urban sewage treatment plant contains a large number of microorganisms, bacteria, viruses and other pathogens. If the sewage without disinfection treatment is directly discharged into the water body, it will lead to the spread of pathogens through different channels and cause health risks. Therefore, the disinfection process unit in sewage treatment is crucial. At present, the main disinfection method used in urban sewage treatment plants in China is chlorine disinfection.

[0003] However, the operation control of the disinfection process unit of the urban sewage treatment plant still faces a series of problems: ①There is a lag in using fecal coliform count as the control index of disinfection effect. The detection time of fecal coliform count by multi-tube fermentation method is 48h, which cannot judge the disinfection effect of effluent in real time. When natural disasters or public health incidents occur, the number of pathogens in the sewage system increases greatly, and this detection method cannot ensure that the fecal coliform count of effluent meets the standard. ②The addition of chlorine disinfectant has not achieved precise control. At present, the addition of chlorine disinfectant in the disinfection unit of the sewage treatment plant is controlled according to the experience of the operation personnel, and the investigation shows that the sewage plant often over-adds chlorine disinfectant to ensure that the fecal coliform count of effluent meets the standard, which cannot achieve precise addition and dynamic adjustment of chlorine disinfectant. ③Excessive chlorine disinfectant will affect the ecological safety of the receiving water body. Studies have shown that excessive residual chlorine also has a certain toxic effect on aquatic organisms. ④Excessive 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 trihalomethane (THMs) and haloacetic acid (HAAs). These substances have carcinogenicity and mutagenicity, which pose a long-term threat to human health. Especially in sewage with high organic matter content, the generation amount of by-products increases, which increases the pollution risk of water body and affects environmental safety.

[0004] Therefore, there is an urgent need for a control system that can judge whether the fecal coliform count and residual chlorine indicators of effluent meet the standard in real time, and can feedback and control the addition amount of chlorine disinfectant in real time, to ensure that the fecal coliform count and residual chlorine of effluent meet the standard, and to precisely control the addition amount of chlorine disinfectant. SUMMARY

[0005] The present application provides a sewage disinfection system and method to solve the technical problems in the prior art.

[0006] The technical solution of the present application to solve the above technical problems is as follows:

[0007] In a first aspect, a sewage disinfection system is provided, which comprises a sewage disinfection reaction unit, a first monitoring subunit, a disinfectant addition subunit, a second monitoring subunit and a disinfectant control subunit.

[0008] The first monitoring subunit, the disinfectant adding subunit and the second monitoring subunit are connected with the sewage disinfection reaction unit and the disinfectant control subunit, the first monitoring subunit is used to monitor the water inflow of the sewage disinfection reaction unit in real time, the disinfectant adding subunit is used to add disinfectant to the sewage disinfection reaction unit, and the second monitoring subunit is used to monitor the oxidation-reduction potential value of the effluent in the sewage disinfection reaction unit in real time.

[0009] An output end of the disinfectant control subunit is in communication with an input end of the disinfectant adding subunit, so as to regulate the adding amount of the disinfectant adding subunit after data collection of the first monitoring subunit, the disinfectant adding subunit and the second monitoring subunit.

[0010] As a further technical solution, the first monitoring subunit comprises a flow meter and a first sensor arranged on the flow meter, and the flow meter is arranged on the water inflow pipeline of the sewage disinfection reaction unit.

[0011] As a further technical solution, the disinfectant adding subunit comprises a metering pump, a disinfectant storage tank connected with the input end of the metering pump, a second sensor and a controller, and the metering pump is connected with the disinfection reaction tank in the sewage disinfection reaction unit.

[0012] As a further technical solution, the second monitoring subunit comprises an oxidation-reduction potential instrument and a third sensor arranged on the oxidation-reduction potential instrument, and the oxidation-reduction potential instrument is arranged on the effluent channel in the sewage disinfection reaction unit.

[0013] As a further technical solution, the disinfectant control subunit comprises an input module, a central processor, a memory and an output module, an output end of the input module is connected with an input end of the central processor, an output end of the central processor is connected with the output module, the central processor is connected with the memory and realizes bidirectional transmission of data signals;

[0014] The first sensor, the second sensor and the third sensor are connected with the input end of the input module, and an output end of the output module is connected with the controller, so as to control the flow of the metering pump.

[0015] As a further technical solution, a central remote control unit is further included, the central remote control unit is connected with the disinfectant control subunit and realizes bidirectional transmission of data signals.

[0016] The second aspect of the application protects a precise regulation method of a sewage disinfection system, which comprises the system of the first aspect, and the specific steps are as follows:

[0017] S1, obtain the test data of effective chlorine dosage, effluent ORP (oxidation-reduction potential) value, effluent fecal coliform count and effluent residual chlorine value through chlorine disinfectant dosing test, for standby;

[0018] S2, obtain the quantitative relationship model 1 of sewage disinfection effective chlorine dosage-effluent ORP-effluent fecal coliform count by nonlinear surface data fitting, and obtain the quantitative relationship model 2 of disinfection effluent ORP-residual chlorine by polynomial fitting analysis; and preset the disinfection effluent fecal coliform count target value, residual chlorine target value, chlorine disinfectant effective chlorine concentration, effective chlorine dosage calculation model, quantitative relationship model 1 and quantitative relationship model 2 in the disinfectant control subunit;

[0019] S3, the disinfectant control subunit calculates the real-time effective chlorine dosage, effluent fecal coliform count and effluent residual chlorine according to the data signals transmitted by the first monitoring subunit, the disinfectant dosing subunit, the second monitoring subunit and the models preset in the disinfectant control subunit in step S2;

[0020] S4, compare the calculation results of step S3 with the target values preset in the disinfectant control subunit, and send control instructions to the disinfectant dosing subunit according to the comparison results;

[0021] Among them, the target values preset in the disinfectant control subunit are disinfection effluent fecal coliform count target value, residual chlorine target value and chlorine disinfectant effective chlorine concentration.

[0022] As a further technical solution, in step S2, the quantitative relationship model 1 is:

[0023] Among them: is the effluent fecal coliform count (pieces / L), is the effective chlorine dosage (mg / L), is the oxidation-reduction potential (mV), , , , , , is the fitting parameter;

[0024] The quantitative relationship model 2 is:

[0025] Among them: is the effluent residual chlorine value (mg / L), is the oxidation-reduction potential (mV), , , is the fitting parameter;

[0026] The effective chlorine dosage calculation model is ,

[0027] Wherein, is the effective chlorine dosage (mg / L), Q1 is the influent flow value (m 3 / h) of the sewage disinfection reaction unit, Q2 is the disinfectant flow value (m 3 / h) added by the disinfectant adding sub-unit, and k is the effective chlorine concentration (mg / L).

[0028] As a further technical solution, in step S3, the following steps are included:

[0029] S31, the first monitoring sub-unit and the disinfectant adding sub-unit respectively monitor Q1 and Q2 in real time, and transmit the monitored Q1 and Q2 data signals to the disinfectant control sub-unit to calculate the real-time effective chlorine dosage value of the disinfectant adding sub-unit.

[0030] S32, the disinfectant control sub-unit calculates the real-time effluent fecal coliform count according to the effluent ORP monitored by the second monitoring sub-unit, the value in step S31, and the preset quantity relationship model 1.

[0031] The disinfectant control sub-unit calculates the real-time effluent residual chlorine according to the ORP monitored by the second monitoring sub-unit and the preset quantity relationship model 2.

[0032] As a further technical solution, in step S4, there are specifically:

[0033] The disinfectant control sub-unit compares the calculated real-time effluent fecal coliform count and real-time effluent residual chlorine with the target values preset in step S2.

[0034] If the real-time effluent fecal coliform count is < the fecal coliform count target value, and the real-time effluent residual chlorine value is < the residual chlorine target value, the discharge standard is met, the disinfectant control sub-unit sends an instruction to the disinfectant adding sub-unit to maintain the current effective chlorine dosage operation.

[0035] If the real-time effluent fecal coliform count is < the fecal coliform count target value, but the real-time effluent residual chlorine value is ≥ the residual chlorine target value, the disinfectant control sub-unit sends an instruction to the disinfectant adding sub-unit to gradually reduce the chlorine disinfectant dosage until the effluent ORP value feedback real-time residual chlorine < residual chlorine target value, i.e. maintain the effective chlorine dosage operation.

[0036] ​​If the real-time effluent fecal coliform group number is greater than or equal to the target value of the fecal coliform group number, the disinfectant control subunit calculates the corresponding effective chlorine dosage according to the real-time ORP value, the target fecal coliform group number and the preset quantity relationship model 1 Then, Q2 is calculated according to Q1 and the effective chlorine dosage calculation model.

[0037] The disinfectant control subunit sends an instruction to the disinfectant dosing subunit, adjusts the chlorine disinfectant dosing flow value to Q2 calculated immediately, and continuously monitors the effluent ORP value until the effluent ORP value feedback real-time effluent fecal coliform group number is less than the target value of the fecal coliform group number, and the residual chlorine value is less than the target value of the residual chlorine, that is, the effective chlorine dosage is maintained.

[0038] The beneficial effects of the present application are:

[0039] 1. The control system of the present application is simple in composition and convenient to operate. The signals monitored by the first monitoring subunit, the disinfectant dosing subunit and the second monitoring subunit are transmitted to the disinfectant control subunit to control the disinfectant dosing subunit to disinfect the sewage in the sewage disinfection reaction unit. By controlling the disinfectant dosage, the drug consumption and the operation cost of the disinfection process unit are effectively reduced to help the sewage treatment plant to realize energy saving and carbon reduction green operation. The effluent ORP value indicates the sewage disinfection effect, which is equivalent to replacing the fecal coliform group number and the residual chlorine index, improves the stability of the sewage disinfection effluent water quality, and ensures the ecological safety of the effluent;

[0040] 2. The control method of the present application is based on the ORP equivalent principle. The effluent ORP is monitored by the second monitoring subunit, and the quantity relationship model 1 and the quantity relationship model 2 are preset in the disinfectant control subunit to realize the equivalent and accurate calculation of the fecal coliform group number and the residual chlorine value of the disinfection effluent, solve the hysteresis problem of the fecal coliform group routine detection, realize the real-time monitoring of the residual chlorine value of the effluent, and ensure that the fecal coliform group number and the residual chlorine value of the sewage disinfection effluent meet the standards;

[0041] 3. The control method of the present application simplifies the operation and maintenance work process of the sewage treatment plant, improves the intelligent operation and management of the sewage treatment plant, and realizes the digitization and intelligentization of the sewage disinfection process unit. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 The connection structure block diagram of the sewage disinfection system of the present application;

[0043] Figure 2 The structure block diagram of the first monitoring subunit of the present application;

[0044] Figure 3 The structure block diagram of the disinfectant dosing subunit of the present application;

[0045] Figure 4The structure block diagram of the second monitoring subunit of the present application;

[0046] Figure 5 The structure block diagram of the disinfectant control subunit of the present application;

[0047] Figure 6 The structure block diagram of the central remote control unit of the present application;

[0048] Figure 7 The quantity relationship model 1 in the embodiment 2 of the present application;

[0049] Figure 8 The quantity relationship model 2 in the embodiment 2 of the present application.

[0050] In the drawings, the components represented by each reference numeral are listed as follows:

[0051] Sewage disinfection reaction unit 10, water inlet pipeline 11, disinfection reaction tank 12, water outlet channel 13;

[0052] First monitoring subunit 20, flow meter 21, first sensor 22;

[0053] Disinfectant adding subunit 30, metering pump 31, disinfectant storage tank 32, second sensor 33, controller 34;

[0054] Second monitoring subunit 40, oxidation-reduction potential instrument 41, third sensor 42;

[0055] Disinfectant control subunit 50, input module 51, central processing unit 52, memory 53, output module 54;

[0056] Central remote control unit 60, data server 61, application server 62, security gateway 63. DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0058] In the description of the present application, the terms “first” and “second” are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with “first” and “second” can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of “multiple” is two or more, unless otherwise specifically limited.

[0059] In the description of the present application, the word "for example" is used to indicate "serving as an example, instance, or illustration." Any embodiment described as "for example" in this application is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the application. In the following description, for purposes of explanation, specific details are set forth. It will be apparent to those skilled in the art that the present application can be practiced without the specific details. In other instances, well-known structures and processes are not shown in detail to avoid obscuring the application. Thus, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features presented herein.

[0060] Embodiment 1

[0061] In order to effectively treat sewage, for example, sewage disinfection, by monitoring the influent flow, effluent ORP, effective chlorine dosage and feeding back to the control system, the operator adjusts the disinfectant dosage according to the judgment to realize the dosage control of disinfectant, see Figure 1 The present embodiment provides a sewage disinfection system, comprising a sewage disinfection reaction unit 10, a first monitoring sub-unit 20, a disinfectant dosing sub-unit 30, a second monitoring sub-unit 40, a disinfectant control sub-unit 50, and a central remote control unit 60.

[0062] The first monitoring sub-unit 20, the disinfectant dosing sub-unit 30, and the second monitoring sub-unit 40 are connected with the sewage disinfection reaction unit 10 and the disinfectant control sub-unit 50. The first monitoring sub-unit 20 is used to monitor the influent flow of the sewage disinfection reaction unit 10 in real time. The disinfectant dosing sub-unit 30 is used to dose disinfectant into the sewage disinfection reaction unit 10. The second monitoring sub-unit 40 is used to monitor the oxidation-reduction potential value of the effluent in the sewage disinfection reaction unit 10 in real time. At the same time, the first monitoring sub-unit 20 feeds back the real-time monitored influent flow value to the disinfectant control sub-unit 50.

[0063] An output end of the disinfectant control sub-unit 50 is in communication with an input end of the disinfectant dosing sub-unit 30, so as to regulate the dosage of the disinfectant dosing sub-unit 30 after data collection of the first monitoring sub-unit 20, the disinfectant dosing sub-unit 30, and the second monitoring sub-unit 40.

[0064] The central remote control unit 60 is connected with the disinfectant control sub-unit 50 and realizes bidirectional transmission of data signals.

[0065] It can be explained that the disinfectant in the embodiment can be chlorine disinfectant; the sewage disinfection reaction unit 10 is used for the disinfection contact reaction process of sewage.

[0066] In the process of implementation, referring to 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 pipeline 11 of the sewage disinfection reaction unit 10 to monitor the flow 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.

[0067] In the process of implementation, referring to Figure 3 , the disinfectant adding subunit 30 includes a metering pump 31, a disinfectant storage tank 32 connected with the input end of the metering pump 31, a second sensor 33, and a controller 34, the metering pump 31 is connected with 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 arranged on the metering pump 31, the flow data of the metering pump 31 is monitored in real time through 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 of the metering pump 31.

[0068] In the process of implementation, referring to Figure 4 , the second monitoring subunit 40 includes an oxidation-reduction potential instrument 41 and a third sensor 42 arranged on the oxidation-reduction potential instrument 41, the oxidation-reduction potential instrument 41 is arranged on the water outlet channel 13 in the sewage disinfection reaction unit 10 to monitor the oxidation-reduction potential value of the water after disinfection in real time; and the third sensor 42 is used to read the data of the oxidation-reduction potential instrument 41 in real time and transmit the data to the disinfectant control subunit 50.

[0069] In the process of implementation, referring to 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, one output end of the input module 51 is connected with one input end of the central processing unit 52, one output end of the central processing unit 52 is connected with the output module 54, the central processing unit 52 is connected with 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 connected with the input end of the input module 51, one output end of the output module 54 is connected with the controller 34 to control the flow of the metering pump 31.

[0070] It can be explained that the first sensor 22, the second sensor 33 and the third sensor 42 are connected with the input module 51, and it can be known that the input module 51 is used at least to receive relevant data detected by each sensor; the memory 53 is used to store system programs and user programs, and the central processing unit 52 transmits data from the input module 51 to the output module 54 after comparison according to programs in the memory 53. The output module 54 is connected with the controller 34, and transmits instructions of the central processing unit 52 to the metering pump 31, so that the disinfectant control subunit 50 realizes regulation and control of the disinfectant adding subunit 30.

[0071] In the specific implementation process, referring to Figure 1 、 Figure 6 The central remote control unit 60 includes a data server 61, an application server 62 and a security gateway 63, the data server 61 is connected with the application server 62 and the security gateway 63 to realize bidirectional transmission of data signals; one output end of the output module 54 is connected with one input end of the security gateway 63 in signal connection, real-time data of the data server 61 is read through the application server 62, the output module 54 transmits program calculation data, results and instructions of the central processing unit 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 data of the first monitoring subunit 20, the disinfectant adding subunit 30, the second monitoring subunit 40 and the disinfectant control subunit 50 through the application server 62, and the user can also send instructions to the disinfectant control subunit 50 through the application server 62 to realize remote regulation and control of the disinfectant adding subunit 30.

[0072] It can be explained that the central remote control unit 50 includes a power supply for providing power supply for the input module 51, the central processing unit 52, the memory 53 and the output module 54.

[0073] It can be explained that in the present application:

[0074] The flow meter 21 can be an ultrasonic flow meter LRF-3000SC or an electromagnetic flow meter ORBLDBE-50-316L-4F; the first sensor 22 can be a KJT-LSA500 flow sensor;

[0075] The metering pump 31 can be a diaphragm metering pump GM170 or an electromagnetic diaphragm metering pump AKS600;

[0076] The second sensor 33 can be an ACU10L-L flow sensor;

[0077] The controller 34 can be a Milton Roy HED1P1C controller or a Pascfi da NEMA4 controller.

[0078] The oxidation-reduction potential instrument 41 can be a JD-ZS6 oxidation-reduction potential instrument or a MIK-MDC oxidation-reduction potential instrument.

[0079] The third sensor 42 can be a Y533-A sensor.

[0080] The input module 51 can be a Siemens EM DE08 or an Omron CJ1W-ID261.

[0081] The central processing unit 52 can be a Siemens CPU SR20 or an Omron CJ1M-CPU13-ETN.

[0082] The memory 53 can be a Siemens 6ES7952-1AM00-0AA0 or an Omron C200H-ME431.

[0083] The output module 54 can be a Siemens EM DR08 or an Omron EM DT08.

[0084] The present application is implemented as follows:

[0085] The disinfectant dosing subunit 30 can be used to add disinfectant to the sewage disinfection reaction unit 10 for disinfection treatment of sewage.

[0086] The first sensor 22 acquires the flow data of the inflow pipe 11 measured by the flow meter 21 in real time, the second sensor 33 acquires the flow data of the metering pump 31 in real time, and the third sensor 42 acquires the effluent ORP data measured by the oxidation-reduction potential instrument 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 memory 53 has a preset effluent ORP control value (ORP≥650mV). When the effluent ORP≥650mV, the effective chlorine dosing amount is maintained, and when the effluent ORP<650mV, the central processing unit 52 sends a command to increase the dosing amount of the metering pump 31 until the effluent ORP≥650mV. The output module 54 transmits the real-time data signals of the central processing unit 52 to the data server 61 through the security gateway 63, and the user can retrieve the real-time data signals through the application server 62, or send a command to the disinfectant control subunit 50 to remotely control the disinfectant dosing subunit 30. That is, by monitoring the inflow flow, effluent ORP, and effective chlorine dosing amount of sewage, and feeding these values back to the disinfectant control subunit 50, the dosing amount of disinfectant can be controlled, which is low in cost and good in effect.

[0087] Example 2

[0088] The embodiment provides a precise control method of a sewage disinfection system, which can be described as follows: the method comprises the system in the embodiment 1, so as to determine whether the fecal coliform group number and the residual chlorine index of effluent water meet the standards through the system in the embodiment 1, and to feed back and precisely control the front-end chlorine disinfectant dosage in real time, and the specific steps of the method are as follows:

[0089] S1, obtaining the test data of effective chlorine dosage, effluent ORP value, effluent fecal coliform group number and effluent residual chlorine value through a chlorine disinfectant dosage test, for standby use;

[0090] S2, obtaining a quantity relationship model 1 of sewage disinfection effective chlorine dosage-effluent ORP-effluent fecal coliform group number through nonlinear surface data fitting, and obtaining a quantity relationship model 2 of disinfection effluent ORP-residual chlorine through polynomial fitting analysis; and presetting a disinfection effluent fecal coliform group number target value, a residual chlorine target value, a chlorine disinfectant effective chlorine concentration, an effective chlorine dosage calculation model, the quantity relationship model 1 and the quantity relationship model 2 in the disinfectant control subunit.

[0091] In this step, the quantity relationship model 1 is as follows:

[0092] Among them: the effluent fecal coliform group number (piece / L), the effective chlorine dosage (mg / L), the oxidation-reduction potential (mV), , , , , , the fitting parameters;

[0093] The quantity relationship model 2 is as follows:

[0094] Among them: the effluent residual chlorine value (mg / L), the oxidation-reduction potential (mV), , , the fitting parameters;

[0095] The effective chlorine dosage calculation model is as follows: ,

[0096] Among them, the effective chlorine dosage (mg / L), Q1 is the influent flow value (m 3 / h) of the sewage disinfection reaction unit, Q2 is the disinfectant flow value (m 3 / h) added by the disinfectant adding subunit, and k is the effective chlorine concentration (mg / L).

[0097] S3, the disinfectant control subunit calculates the real-time effective chlorine dosage, the effluent fecal coliform count and the effluent residual chlorine according to the data signals transmitted by the first monitoring subunit, the disinfectant dosing subunit, the second monitoring subunit and the model preset in the disinfectant control subunit in step S2;

[0098] This step includes: S31, the first monitoring subunit and the disinfectant dosing subunit respectively monitor Q1 and Q2 in real time, 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;

[0099] S32, the disinfectant control subunit calculates the real-time effluent fecal coliform count according to the real-time monitored effluent ORP of the second monitoring subunit, the value in step S31 and the preset quantity relationship model 1;

[0100] The disinfectant control subunit calculates the real-time effluent residual chlorine according to the real-time monitored ORP of the second monitoring subunit and the preset quantity relationship model 2.

[0101] S4, compare the calculation results of step S3 with the target values preset in the disinfectant control subunit, and send control instructions to the disinfectant dosing subunit according to the comparison results;

[0102] Among them, the target values preset in the disinfectant control subunit are the fecal coliform count target value, the residual chlorine target value and the effective chlorine concentration of the chlorine disinfectant.

[0103] 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 values preset in step S2:

[0104] If the real-time effluent fecal coliform count is less than the fecal coliform count target value, and the real-time effluent residual chlorine value is less than the residual chlorine target value, the discharge standard is met, the disinfectant control subunit sends instructions to the disinfectant dosing subunit to maintain the current effective chlorine dosage;

[0105] If the real-time effluent fecal coliform count is less than the fecal coliform count target value, but the real-time effluent residual chlorine value is greater than or equal to the residual chlorine target value, the disinfectant control subunit sends instructions to the disinfectant dosing subunit to gradually reduce the chlorine disinfectant dosage until the real-time residual chlorine is less than the residual chlorine target value according to the feedback of the effluent ORP value, that is, to maintain the current effective chlorine dosage;

[0106] If the real-time effluent fecal coliform count is greater than or equal to the target fecal coliform count, the disinfectant control subunit calculates the corresponding effective chlorine dosage based on the real-time ORP value, the target fecal coliform count, and the preset quantitative relationship model 1. Then, Q2 is calculated based on Q1 and the effective chlorine dosage calculation model. The disinfectant control subunit sends an instruction to the disinfectant dosing subunit to immediately adjust the chlorine disinfectant dosing flow rate to the target value Q2, and continuously monitors the effluent ORP value until the real-time effluent fecal coliform count is less than the target value and the residual chlorine value is less than the target value, that is, to maintain the effective chlorine dosage.

[0107] The following experiment was conducted on the chlorine disinfectant dosing of influent samples from a wastewater treatment plant to obtain quantitative relationship model 1 and quantitative relationship model 2 for the wastewater treatment plant.

[0108] A certain amount of chlorine disinfectant (effective chlorine dosage gradient: 1.0, 2.0, 3.0, 4.0, 5.0 mg / L) was added to the influent water sample for disinfection. After a certain time (e.g., time gradient: 0, 5, 10, 20, 30 min) at room temperature (25℃), the sample was taken to determine the oxidation-reduction potential (ORP), fecal coliform count, and residual chlorine value, as shown in Table 1 below.

[0109]

[0110] Nonlinear surface fitting analysis was performed on the effective chlorine dosage, redox potential, and fecal coliform count in the chlorine disinfectant addition experiment data to establish a Poly2D function, where x is the effective chlorine dosage (mg / L) and y is the redox potential (mV). The number of fecal coliforms (CFU / L) is used to fit the fecal coliform count. With available chlorine dosage and redox potential Quantitative Relationship Model =f(x, y);

[0111] fecal coliform count The quantitative relationship model between effective chlorine dosage x and redox potential y is as follows: Figure 7 As shown.

[0112] Polynomial fitting analysis was performed on the effluent oxidation-reduction potential and residual chlorine content in the chlorine disinfectant dosing experiment data, setting... The residual chlorine value of the effluent (mg / L) Given the redox potential (mV), establish the residual chlorine... With redox potential Quantitative Relationship Model =f(y), as follows:

[0113]

[0114] Residual chlorine With redox potential Quantitative Relationship Model =f(y) Figure 8 As shown.

[0115] In actual operation, the disinfection influent flow rate is set to Q1 (m³). 3 / h), the flow rate of the chlorine disinfection metering pump is Q2 (m 3 / h), a wastewater treatment plant uses sodium hypochlorite solution with an effective chlorine content of 10% (i.e., an effective chlorine concentration of 10) as the chlorine disinfectant. 5 mg / L), effective chlorine dosage of the chlorine disinfectant dosing system The computational model x=f(Q1,Q2) is as follows:

[0116]

[0117] Wastewater treatment plant A complies with the Class A discharge standard of the "Discharge Standard of Pollutants for Urban Wastewater Treatment Plants" (GB18918-2002), requiring the effluent fecal coliform count to be <1000 CFU / L. To ensure that the disinfected effluent does not affect the ecological safety of the water body after entering the environment, the residual chlorine value of the disinfected effluent is limited to <0.2 mg / L. To control the fecal coliform count and residual chlorine in the disinfected effluent to not exceed the standards, the target values ​​for the effluent fecal coliform count are preset in the storage tank to be ≤900 CFU / L and the target value for the effluent residual chlorine to be ≤0.2 mg / L, with the target value for the effluent fecal coliform count having a higher priority than the target value for the effluent residual chlorine. Quantitative relationship model 1, quantitative relationship model 2, and effective chlorine dosage calculation model are obtained through pre-set experiments in the storage tank.

[0118] The disinfectant control subunit acquires the disinfection influent flow rate Q1 and the metering pump flow rate Q2 in real time, and the central processing unit calculates the current effective chlorine dosage based on the data signals and a preset calculation model. The disinfectant control subunit acquires real-time ORP data of the disinfected effluent and calculates the real-time fecal coliform count and residual chlorine value using preset quantitative relationship models 1 and 2. The central processing unit compares the calculated real-time fecal coliform count and residual chlorine value of the effluent with preset target values.

[0119] When the real-time fecal coliform count is ≤900 / L, the residual chlorine value is continuously compared, if the residual chlorine value is ≤0.2 mg / L, the disinfectant control sub-unit sends an instruction to the disinfectant dosing sub-unit to maintain the current effective chlorine dosage to continue running. If the residual chlorine value is >0.2 mg / L, the disinfectant control sub-unit sends an instruction to the disinfectant dosing sub-unit to reduce the metering pump flow rate and reduce the effective chlorine dosage until the real-time residual chlorine value is ≤0.2 mg / L.

[0120] When the real-time fecal coliform count is >900 / L, the disinfectant control sub-unit calculates the corresponding effective chlorine dosage according to the number relationship model 1, the real-time ORP value and the fecal coliform count =900 / L, and sends an instruction to the disinfectant dosing sub-unit to immediately increase the metering pump flow rate and increase the chlorine disinfectant dosage to the target value, 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 real-time effluent fecal coliform count is ≤900 / L and the residual chlorine value is ≤0.2 mg / L, i.e. maintaining the current effective chlorine dosage to run; the disinfectant control sub-unit sends a dynamic adjustment instruction to the disinfectant dosing sub-unit according to the comparison result to ensure that the disinfection effluent fecal coliform count is stably below 900 / L and the residual chlorine value is below 0.2 mg / L, and to realize the equivalent calculation of the disinfection effluent fecal coliform count and the residual chlorine value and the precise regulation of the chlorine disinfectant dosage.

[0121] The disinfectant control sub-unit transmits the disinfection influent real-time flow rate Q1, the metering pump real-time flow rate Q2, the disinfection effluent ORP value, and the calculated real-time effective chlorine dosage x, the real-time fecal coliform count and the residual chlorine value to the central remote control unit. The operating personnel can real-time view the running parameters of the first monitoring sub-unit through the central remote control unit to ensure that the system runs stably, and can also send an instruction to the disinfectant control sub-unit through the central remote control unit to artificially adjust the metering pump flow rate and correct the stored pre-designed calculation model and target value.

[0122] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0123] Although the preferred embodiments of the present application have been described, those skilled in the art can make further changes and modifications to these embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including all the preferred embodiments and all the changes and modifications falling within the scope of the present application.

[0124] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A method for precise control of a wastewater disinfection system, characterized in that, It includes a wastewater 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 wastewater disinfection reaction unit (10) and the disinfectant control subunit (50). The first monitoring subunit (20) is used to monitor the influent flow rate of the wastewater disinfection reaction unit (10) in real time. The disinfectant dosing subunit (30) is used to add disinfectant to the wastewater disinfection reaction unit (10). The second monitoring subunit (40) is used to monitor the oxidation-reduction potential value of the effluent in the wastewater disinfection reaction unit (10) in real time. One output terminal of the disinfectant control subunit (50) is connected to one input terminal 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 dosing amount of the disinfectant dosing subunit (30); The specific steps are as follows: S1. Obtain test data on effective chlorine dosage, effluent ORP value, effluent fecal coliform count, and effluent residual chlorine value through chlorine disinfectant dosing tests, for future reference; S2. A quantitative relationship model 1 is obtained by fitting nonlinear surface data to obtain the effective chlorine dosage for wastewater disinfection, the effluent ORP, and the effluent fecal coliform count. A quantitative relationship model 2 is obtained by multinomial fitting analysis to obtain the effluent ORP and residual chlorine. In the disinfectant control subunit, target values ​​for effluent fecal coliform count, residual chlorine, effective chlorine concentration of chlorine disinfectant, calculation models for effective chlorine dosage, quantitative relationship model 1, and quantitative relationship model 2 are preset. S3. The disinfectant control subunit calculates the real-time effective chlorine dosage, the number of fecal coliforms in the effluent, and the residual chlorine in the effluent based on the data signals transmitted in real time by the first monitoring subunit, the disinfectant dosing subunit, and the second monitoring subunit, as well as the model preset in the disinfectant control subunit in step S2. S4. Compare the calculation result of step S3 with the preset target value in the disinfectant control subunit, and send a control command to the disinfectant dosing subunit according to the comparison result. The target values ​​preset 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.

2. The method according to claim 1, characterized in that, In step S2, the quantitative relationship model 1 is: in: The number of fecal coliforms in the effluent (CFU / L). This refers to the available chlorine dosage (mg / L). The redox potential is denoted as mV. , , , , , These are the fitting parameters; Quantitative Relationship Model 2 is: in: The residual chlorine value of the effluent (mg / L) The redox potential is denoted as mV. , , These are the fitting parameters; The calculation model for available chlorine dosage is as follows: , in, Q1 is the effective chlorine dosage (mg / L), and Q1 is the influent flow rate (m³) of the wastewater disinfection reaction unit. 3 / h), Q2 is the disinfectant flow rate (m³) added by the disinfectant dosing subunit. 3 / h), k is the effective chlorine concentration (mg / L).

3. The method according to claim 2, characterized in that, Step S3 includes the following steps: S31. The first monitoring subunit and the disinfectant dosing subunit respectively monitor Q1 and Q2 in real time, 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, based on the effluent ORP monitored in real time by the second monitoring subunit, and the results of step S31... The real-time fecal coliform count in the effluent is calculated using the value and the preset quantitative relationship model 1. The disinfectant control subunit calculates the real-time residual chlorine in the effluent based on the ORP monitored in real time by the second monitoring subunit and the preset quantitative relationship model 2.

4. The method according to claim 3, characterized in that, Step S4 specifically includes: The disinfectant control subunit compares the calculated real-time fecal coliform count and real-time residual chlorine in the effluent with the preset target values ​​in step S2: If the real-time effluent fecal coliform count is less than the target value for fecal coliform count and the real-time effluent residual chlorine value is less than the target value for residual chlorine, then the discharge standard is met. The disinfectant control subunit sends an instruction to the disinfectant dosing subunit to maintain the current effective chlorine dosing level. If the real-time effluent fecal coliform count is less than the target value, but the real-time effluent residual chlorine value is greater than or equal to the target value, the disinfectant control subunit sends an instruction to the disinfectant dosing subunit to gradually reduce the chlorine disinfectant dosage until the effluent ORP value feedback shows that the real-time residual chlorine is less than the target value, that is, the effective chlorine dosage is maintained. If the real-time effluent fecal coliform count is greater than or equal to the target fecal coliform count, the disinfectant control subunit calculates the corresponding effective chlorine dosage based on the real-time ORP value, the target fecal coliform count, and the preset quantitative relationship model 1. Then, Q2 is calculated based on Q1 and the effective chlorine dosage calculation model; The disinfectant control subunit sends an instruction to the disinfectant dosing subunit to immediately adjust the chlorine disinfectant dosing flow rate 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 value and the residual chlorine value is less than the target value, that is, to maintain the effective chlorine dosing amount.

5. The method according to claim 1, characterized in that, The first monitoring subunit (20) includes a flow meter (21) and a first sensor (22) installed on the flow meter (21). The flow meter (21) is installed on the inlet pipe (11) of the wastewater disinfection reaction unit (10).

6. The method according to claim 5, characterized in that, The disinfectant dosing subunit (30) includes a metering pump (31) and a disinfectant storage tank (32), a second sensor (33), and a controller (34) connected to the input end of the metering pump (31). The metering pump (31) is connected to the disinfection reaction tank (12) in the wastewater disinfection reaction unit (10).

7. The method according to claim 6, characterized in that, The second monitoring subunit (40) includes an oxidation-reduction potentiometer (41) and a third sensor (42) installed on the oxidation-reduction potentiometer (41). The oxidation-reduction potentiometer (41) is installed on the effluent channel (13) in the wastewater disinfection reaction unit (10).

8. The method according to claim 7, characterized in that, The disinfectant control subunit (50) includes an input module (51), a central processing unit (52), a memory (53), and an output module (54). One output terminal of the input module (51) is connected to one input terminal of the central processing unit (52), and one output terminal 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 sensor (33), and the third sensor (42) are all connected to the input terminal of the input module (51), and one output terminal of the output module (54) is connected to the controller (34) to control the flow rate of the metering pump (31).

9. The method according to claim 8, characterized in that, It also includes a central remote control unit (60), which is connected to the disinfectant control subunit (50) and realizes bidirectional transmission of data signals.

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