An open-loop and closed-loop composite control system for automatic dosing of sulfuric acid in reclaimed water

Abstract

The present invention provides an open-loop and closed-loop composite control system for automatic dosing of sulfuric acid in reclaimed water, which belongs to the technical field of automatic dosing control, and includes: obtaining a first real-time pH value of a variable-pore filter and determining a first deviation value; obtaining a second real-time pH value of a clarification zone of a machine-added pool and a water inlet flow rate of the machine-added pool to determine a required concentrated sulfuric acid flow rate; determining the required real-time frequency of a concentrated sulfuric acid dosing pump based on the first deviation value and the required concentrated sulfuric acid flow rate, and performing open-loop control on the concentrated sulfuric acid dosing pump; obtaining a third real-time pH value of a variable-pore filter after the start of open-loop control, and determining an adjusted amount, and performing closed-loop control on the concentrated sulfuric acid dosing pump based on the adjusted amount and the first deviation value at the corresponding time. The corresponding sulfuric acid flow rate is determined by measuring the deviation between the set value and the water inlet of the machine-added pool, and the frequency of the dosing pump is determined for open-loop control, and the adjusted amount is determined by the difference for closed-loop control, so that the control is more accurate.

Description

Technical Field

[0001] The invention relates to the technical field of automatic dosing control, in particular to an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid. Background Art

[0002] The sulfuric acid dosing control system for reclaimed water adopts the traditional PID closed-loop control method. Due to the large capacity of the reclaimed water machine and the large inertia of PH adjustment, the control system has frequent and large adjustments. Weakening the PID parameters makes it impossible for the system to accurately adjust the PH value, and there are large dynamic and static deviations. The traditional PID control method can no longer meet the on-site control requirements. The sulfuric acid dosing system at the inlet of the variable pore filter often requires manual input of frequency to adjust the PH. The personnel operation is frequent and the manual control accuracy cannot meet the on-site needs.

[0003] Therefore, the present invention provides a reclaimed water sulfuric acid dosing control system with open and closed loop composite control, which can meet the control requirements of on-site pH value while reducing manual operations, and realize continuous control of the frequency conversion of the sulfuric acid dosing pump to reduce the phenomenon of frequent and large-scale adjustment of the frequency converter and improve the service life of the equipment. Summary of the invention

[0004] The present invention provides an open-loop and closed-loop composite control system for automatically dosing sulfuric acid in reclaimed water, which is used to obtain the pH values ​​of the clarification zone of the variable pore filter and the machine-added tank and compare them with preset values ​​to obtain a deviation value, and then determine the required concentrated sulfuric acid flow rate through the water inlet flow rate, determine the real-time frequency of the dosing pump based on the deviation value and the concentrated sulfuric acid flow rate to perform open-loop control, and determine the regulated amount by comparing the calculated real-time value with the actual real-time value at the corresponding time to perform closed-loop control.

[0005] The present invention provides an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water, comprising:

[0006] Deviation determination module: used for obtaining a first real-time pH value of the variable pore filter and determining a first deviation value between the first real-time pH value and a set pH value;

[0007] Flow determination module: used to obtain the second real-time pH value of the clarification zone of the machining pool and the water inlet flow of the machining pool, and determine the required concentrated sulfuric acid flow based on the water inlet flow and the second real-time pH value;

[0008] An open-loop control module: used to determine the real-time frequency required by the concentrated sulfuric acid dosing pump based on the first deviation value and the required concentrated sulfuric acid flow rate, and perform open-loop control on the concentrated sulfuric acid dosing pump based on the real-time frequency;

[0009] Closed-loop control module: used to obtain the third real-time pH value of the variable pore filter after the start of open-loop control, and determine the adjusted amount based on the difference between the third real-time pH value and the first real-time pH value, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the adjusted amount and the first deviation value at the corresponding time.

[0010] Preferably, the deviation determination module comprises:

[0011] A first value acquisition unit is used to establish a pH real-time monitoring system based on a pH meter to perform real-time monitoring on the variable pore filter to be monitored, and determine a first real-time pH value of the variable pore filter;

[0012] The deviation determination unit is used to obtain the working requirements of the variable pore filter, determine the set pH value of the variable pore filter at the corresponding time based on the working requirements, and determine a first deviation value between the first real-time pH value and the set pH value at the corresponding time.

[0013] Preferably, the flow determination module includes:

[0014] A second value acquisition unit is used to perform real-time monitoring on the clarification area of ​​the machine-processing tank based on the real-time monitoring system to determine a second real-time pH value of the clarification area of ​​the machine-processing tank;

[0015] The flow determination unit is used to obtain the water inlet hole size and water inlet flow rate of the machining pool, and calculate the water inlet flow of the corresponding machining pool.

[0016] Preferably, the machine-added pool content determination unit is used to obtain a first real-time capacity of the machine-added pool clarification zone, and determine the concentrated sulfuric acid content of the machine-added pool clarification zone at a corresponding time based on the first real-time capacity and the second real-time pH value;

[0017] a required amount determination unit, configured to obtain a second real-time capacity of the variable porosity filter, and determine a real-time concentrated sulfuric acid amount required for the variable porosity filter based on the second real-time capacity and the first deviation value;

[0018] A flow difference determination unit, used to obtain the real-time flow rate between the clarification area of ​​the machine-processing tank and the variable-pore filter tank, and to obtain the flow difference of the clarification area of ​​the machine-processing tank based on the real-time flow rate and the inflow flow rate of the machine-processing tank;

[0019] The flow determination unit is used to determine the real-time concentrated sulfuric acid content required in the clarification zone of the machining pool based on the flow difference and the real-time concentrated sulfuric acid amount required by the variable pore filter, and to determine the concentrated sulfuric acid flow required in the clarification zone of the machining pool in combination with the water inlet flow of the machining pool.

[0020] Preferably, the open-loop control module comprises:

[0021] A frequency determination unit, for determining the total dosage required per unit time of the concentrated sulfuric acid dosing pump based on the concentrated sulfuric acid flow required at the corresponding moment and the first deviation value, and determining the real-time frequency required by the concentrated sulfuric acid dosing pump in combination with the maximum single dosage of the concentrated sulfuric acid dosing pump;

[0022] A frequency difference determination unit is used to set an open-loop control scheme for performing open-loop control on the concentrated sulfuric acid dosing pump according to the real-time frequency at the initial moment, and compare the real-time frequency required by the concentrated sulfuric acid dosing pump at each moment with the frequency at the previous moment to determine whether there is a frequency difference;

[0023] The open-loop control unit is used to adjust the open-loop control scheme corresponding to the previous moment according to the corresponding frequency difference when there is a frequency difference, and to perform open-loop control on the concentrated sulfuric acid dosing pump according to the adjusted open-loop control scheme.

[0024] Preferably, the closed-loop control module comprises:

[0025] A first total amount determination unit is used to obtain the duration of open-loop control of the concentrated sulfuric acid dosing pump and the historical open-loop control scheme, and determine the first total amount of concentrated sulfuric acid entering the clarification area of ​​the machine-adding tank within the corresponding time period based on the historical open-loop control scheme;

[0026] The second total amount determination unit is used to obtain the real-time flow rate between the clarification area of ​​the machine-added pool and the variable porosity filter in the corresponding time period, and determine the total amount of the second concentrated sulfuric acid flowing into the variable porosity filter in the corresponding time period based on the total amount of concentrated sulfuric acid entering the clarification area of ​​the machine-added pool;

[0027] The third value acquisition unit is used to obtain the total flow difference of the variable pore filter in the corresponding time period, and obtain the third real-time pH value of the variable pore filter at the corresponding time based on the total flow difference, the first real-time pH value of the variable pore filter at the initial time and the second total amount of concentrated sulfuric acid.

[0028] Preferably, the closed-loop control module comprises:

[0029] A to-be-adjusted value determination unit, configured to compare the third real-time pH value of the variable pore filter with the first real-time pH value at the corresponding moment to obtain a pH difference, and determine the to-be-adjusted pH value of the corresponding machine-added tank clarification zone based on the pH difference;

[0030] The adjusted amount determining unit is used to determine the required amount of concentrated sulfuric acid flow in the machining pool clarification zone based on the pH value to be adjusted in the machining pool clarification zone and the flow difference in the machining pool clarification zone at the corresponding time, and determine the adjusted amount based on the amount to be adjusted;

[0031] The closed-loop control unit is used to determine a closed-loop control scheme based on the regulated amount and the first deviation value at the corresponding moment, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the closed-loop control scheme.

[0032] Preferably, the controlled variable determining unit includes:

[0033] A coefficient determination block is used to obtain the working environment of the machine-processed pool clarification area and the working parameters under the corresponding working environment, and determine the pH value floating coefficient of the machine-processed pool clarification area under the corresponding working environment based on the working parameters;

[0034]

[0035]

[0036] in, is the pH floating coefficient, is the temperature weight coefficient, is the environmental weight coefficient, n is the number of pH value collections per unit time, is the maximum allowable temperature value, is the minimum allowable temperature value, is the temperature value when the ith pH value is collected, is the actual usage capacity of the clarification area of ​​the pool at the time of pH value collection for the i-th time, The standard usage capacity of the clarification area of ​​the machine pool;

[0037] The ratio comparison block is used to obtain the ratio between multiple pH values ​​to be adjusted in the clarification area of ​​the machine-added pool and the second real-time pH value within a unit time, and compare each ratio with the pH value floating coefficient to determine the comparison coefficient;

[0038]

[0039] Where D1 represents the contrast coefficient; Indicates the number of pH values ​​to be adjusted;

[0040] An adjustment determination block, for when there is a comparison coefficient greater than a preset coefficient and the number satisfies a preset threshold, then there is no need to adjust the concentrated sulfuric acid flow rate;

[0041] Otherwise, the flow rate of concentrated sulfuric acid needs to be adjusted;

[0042] The block for determining the amount to be adjusted is used to obtain the integral of the difference between each second real-time pH value of the clarification zone of the machine-added pool and the pH value to be adjusted within a unit time, and obtain the total flow difference of the clarification zone of the machine-added pool within a unit time, and determine the amount to be adjusted of the required concentrated sulfuric acid flow rate within the corresponding unit time based on the integral of the difference and the total flow difference;

[0043] A block for determining a frequency to be adjusted, for determining the total concentrated sulfuric acid flow rate per unit time of the concentrated sulfuric acid dosing pump after adjustment based on the amount to be adjusted and the concentrated sulfuric acid flow rate required at the corresponding moment, and determining the working frequency to be adjusted of the concentrated sulfuric acid dosing pump based on the total concentrated sulfuric acid flow rate;

[0044] The controlled quantity determination block is used to compare the working frequency to be adjusted with the working frequency required by the concentrated sulfuric acid dosing pump at the corresponding moment, and determine the controlled quantity based on the comparison result.

[0045] Compared with the prior art, the beneficial effects of the present application are as follows: the required concentrated sulfuric acid flow rate is calculated by obtaining the deviation between the pH of the variable pore filter distribution tank and the set value, the pH value of the clarification area of ​​the machine-added tank, and the water inlet flow of the machine-added tank, and then the required frequency of the dosing pump is calculated based on the frequency of the concentrated sulfuric acid dosing pump. The concentrated sulfuric acid dosing pump is open-loop controlled, and the dosing pump frequency is adjusted in advance according to the incoming water flow and pH changes to improve the rapidity of the control system. The deviation control compensation between the regulated quantity and the set value is introduced to effectively improve the static deviation of the system, that is, to improve the accuracy of the system.

[0046] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0047] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0049] Figure 1 The present invention is a structural diagram of an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid in water according to an embodiment of the present invention. DETAILED DESCRIPTION

[0050] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0051] The embodiment of the present invention provides an open-loop and closed-loop composite control system for automatically adding sulfuric acid to water, such as Figure 1 As shown, including:

[0052] Deviation determination module: used for obtaining a first real-time pH value of the variable pore filter and determining a first deviation value between the first real-time pH value and a set pH value;

[0053] Flow determination module: used to obtain the second real-time pH value of the clarification zone of the machining pool and the water inlet flow of the machining pool, and determine the required concentrated sulfuric acid flow based on the water inlet flow and the second real-time pH value;

[0054] An open-loop control module: used to determine the real-time frequency required by the concentrated sulfuric acid dosing pump based on the first deviation value and the required concentrated sulfuric acid flow rate, and perform open-loop control on the concentrated sulfuric acid dosing pump based on the real-time frequency;

[0055] Closed-loop control module: used to obtain the third real-time pH value of the variable pore filter after the start of open-loop control, and determine the adjusted amount based on the difference between the third real-time pH value and the first real-time pH value, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the adjusted amount and the first deviation value at the corresponding time.

[0056] In this embodiment, the first real-time pH value is a value obtained by measuring the pH value of the variable pore filter in real time.

[0057] In this embodiment, the set pH value is the pH value required by the variable pore filter in the corresponding working environment, and the set pH value is different in different working environments.

[0058] In this embodiment, the first deviation value is the difference between the first real-time pH value and the set pH value at the corresponding moment, and the first deviation value at different moments may be different.

[0059] In this embodiment, the second real-time pH value is a value obtained by measuring the pH value of the clarification zone of the machining pool in real time.

[0060] In this embodiment, the water inlet flow rate of the machining pool is related to the size of the water inlet hole of the machining pool and the water flow rate of the inlet water. The greater the water flow rate and the larger the size of the water inlet hole, the greater the water inlet flow rate.

[0061] In this embodiment, the concentrated sulfuric acid flow rate is calculated by determining the real-time concentrated sulfuric acid amount required for the variable pore filter in combination with the first deviation value and combining it with the water inlet flow rate of the machining pool.

[0062] In this embodiment, the dosing amount of the concentrated sulfuric acid dosing pump within a unit period can be controlled by controlling the frequency of the concentrated sulfuric acid dosing pump and the single dosing amount of the concentrated sulfuric acid dosing pump. Therefore, once the dosing amount is determined, the dosing frequency of the concentrated sulfuric acid dosing pump can be determined by the dosing amount.

[0063] In this embodiment, the open-loop control refers to a process of calculating the dosing frequency of the concentrated sulfuric acid dosing pump and controlling the concentrated sulfuric acid dosing pump to operate according to the calculated dosing frequency.

[0064] In this embodiment, the third real-time pH value is obtained by calculating the total amount of concentrated sulfuric acid entering the clarification zone of the machine-added pool after the start of open-loop control and further determining the changed pH value of the variable pore filter, and comparing it with the first real-time pH value of the variable pore filter at the initial moment.

[0065] In this embodiment, the adjusted amount specifically refers to the adjusted amount of the concentrated sulfuric acid dosing pump frequency. By comparing the first real-time pH value with the third real-time pH value, the error generated during the dosing process can be obtained and the specific adjustment frequency can be determined based on the error.

[0066] In this embodiment, the closed-loop control refers to a process of adjusting the dosing frequency of the concentrated sulfuric acid dosing pump determined by the open-loop control through the calculated controlled variable to reduce the error.

[0067] The beneficial effects of the above technical solution are: by obtaining the deviation between the pH of the variable pore filter distribution tank and the set value, as well as the pH value of the clarification area of ​​the machine-added tank and the water inlet flow of the machine-added tank, the required concentrated sulfuric acid flow rate is calculated, and then the required frequency of the dosing pump is calculated based on the frequency of the concentrated sulfuric acid dosing pump, and the concentrated sulfuric acid dosing pump is open-loop controlled, and the dosing pump frequency is adjusted in advance according to the incoming water flow and pH changes, thereby improving the rapidity of the control system, and introducing deviation control compensation between the regulated quantity and the set value, which can effectively improve the static deviation of the system, that is, improve the accuracy of the system.

[0068] The embodiment of the present invention provides an open-loop and closed-loop compliant control system for automatic dosing of sulfuric acid in reclaimed water, and a deviation determination module, including:

[0069] A first value acquisition unit is used to establish a pH real-time monitoring system based on a pH meter to perform real-time monitoring on the variable pore filter to be monitored, and determine a first real-time pH value of the variable pore filter;

[0070] The deviation determination unit is used to obtain the working requirements of the variable pore filter, determine the set pH value of the variable pore filter at the corresponding time based on the working requirements, and determine a first deviation value between the first real-time pH value and the set pH value at the corresponding time.

[0071] In this embodiment, the pH meter is used to obtain the pH value, and the pH real-time monitoring system is used to control the pH meter to obtain the pH value of the variable pore filter in real time, and to record the pH value obtained by the pH meter in real time.

[0072] In this embodiment, the working requirements of the variable pore filter determine the set pH values ​​of the variable pore filter at different times. For example, if the pH value required for working stage 1 is 4 and the pH value required for working stage 2 is 5, then the set pH value of time period 1 corresponding to working stage 1 is 4, and the set pH value of time period 2 corresponding to working stage 2 is 5.

[0073] In this embodiment, the first deviation value will change with the change of the first real-time pH value and the set pH value. For example, the first real-time pH value at moment 1 is 4, and the set pH value of time period 1 corresponding to moment 1 is 4, then the first deviation value at moment 1 is 0, the first real-time pH value at moment 2 is 3.8, and the set pH value of time period 1 corresponding to moment 2 is 4, then the first deviation value at moment 2 is 0.2.

[0074] The beneficial effects of the above technical solution are: by establishing a real-time monitoring system through a pH meter, real-time monitoring of the pH value of the variable pore filter can be achieved, which can ensure the timeliness of the data, determine the set pH value corresponding to different times through the working requirements of the variable pore filter, and calculate the first deviation value, thereby ensuring that the set value can meet the working requirements and further ensuring the accuracy of the open-loop control.

[0075] The embodiment of the present invention provides an open-loop and closed-loop compliant control system for automatic dosing of sulfuric acid in reclaimed water, and a flow determination module, comprising:

[0076] A second value acquisition unit is used to perform real-time monitoring on the clarification area of ​​the machine-processing tank based on the real-time monitoring system to determine a second real-time pH value of the clarification area of ​​the machine-processing tank;

[0077] The flow determination unit is used to obtain the water inlet hole size and water inlet flow rate of the machining pool, and calculate the water inlet flow of the corresponding machining pool.

[0078] In this embodiment, the size of the water inlet hole of the machining pool is fixed, but the water flow rate of the inlet water is not fixed. Therefore, the water flow rate needs to be monitored during operation. The faster the water flow rate, the greater the water inlet flow rate of the machining pool, and the slower the water flow rate, the smaller the water inlet flow rate of the machining pool.

[0079] The beneficial effects of the above technical solution are: by using the real-time monitoring system to monitor the clarification area of ​​the machine-processed pool in real time, the second real-time pH value of the clarification area of ​​the machine-processed pool is obtained, thereby ensuring the timeliness of the acquisition of the second real-time pH value data, and the water inlet flow rate of the machine-processed pool is calculated by obtaining the water inlet hole size of the machine-processed pool and the water flow rate of the inlet water, thereby ensuring the accuracy of the water inlet flow rate, and further ensuring the accuracy of the concentrated sulfuric acid flow rate determined subsequently.

[0080] The embodiment of the present invention provides an open-loop and closed-loop compliant control system for automatic dosing of sulfuric acid in reclaimed water, and a flow determination module, comprising:

[0081] A machine-processing tank content determination unit, used to obtain a first real-time capacity of a clarification zone of the machine-processing tank, and determine the concentrated sulfuric acid content of the clarification zone of the machine-processing tank at a corresponding time based on the first real-time capacity and the second real-time pH value;

[0082] a required amount determination unit, configured to obtain a second real-time capacity of the variable porosity filter, and determine a real-time concentrated sulfuric acid amount required for the variable porosity filter based on the second real-time capacity and the first deviation value;

[0083] A flow difference determination unit, used to obtain the real-time flow rate between the clarification area of ​​the machine-processing tank and the variable-pore filter tank, and to obtain the flow difference of the clarification area of ​​the machine-processing tank based on the real-time flow rate and the inflow flow rate of the machine-processing tank;

[0084] The flow determination unit is used to determine the real-time concentrated sulfuric acid content required in the clarification zone of the machining pool based on the flow difference and the real-time concentrated sulfuric acid amount required by the variable pore filter, and to determine the concentrated sulfuric acid flow required in the clarification zone of the machining pool in combination with the water inlet flow of the machining pool.

[0085] In this embodiment, the first real-time capacity refers to the capacity of the clarification zone of the machine-added pool at the current moment. The first real-time capacity and the second real-time pH value can be used to determine the number of hydrogen ions in the clarification zone of the machine-added pool at the corresponding moment, and further determine the concentrated sulfuric acid content in the clarification zone of the machine-added pool.

[0086] In this embodiment, the second real-time capacity refers to the capacity of the variable pore filter at the current moment. The second implementation capacity and the corresponding first deviation value can be used to determine the number of hydrogen ions currently required by the variable pore filter, and further determine the real-time concentrated sulfuric acid amount required by the variable pore filter.

[0087] In this embodiment, the real-time flow rate refers to the flow rate between the clarification zone of the machine-added tank and the variable pore filter. By adjusting the real-time flow rate and the pH value of the clarification zone of the machine-added tank, the pH value of the variable pore filter can be adjusted to reach the set pH value.

[0088] In this embodiment, the flow difference of the machine-added pool clarification zone refers to the difference between the water inlet and water outlet of the machine-added pool clarification zone, that is, the difference between the water inlet of the machine-added pool clarification zone and the water outlet of the machine-added pool clarification zone flowing into the variable pore filter.

[0089] The beneficial effect of the above technical solution is: by obtaining the real-time capacity of the machine-added pool clarification area and the variable pore filter and combining it with the second real-time pH value and the first deviation value, the real-time concentrated sulfuric acid flow rate required for the variable pore filter is obtained, and then the concentrated sulfuric acid flow rate required for the machine-added pool clarification area is determined by obtaining the flow difference of the machine-added pool clarification area and combining it with the concentrated sulfuric acid flow rate required for the variable pore filter, thereby ensuring the accuracy of the required concentrated sulfuric acid flow rate and providing data support for the subsequent calculation of the frequency of the concentrated sulfuric acid dosing pump.

[0090] The embodiment of the present invention provides an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water, and the open-loop control module includes:

[0091] A frequency determination unit, for determining the total dosage required per unit time of the concentrated sulfuric acid dosing pump based on the concentrated sulfuric acid flow required at the corresponding moment and the first deviation value, and determining the real-time frequency required by the concentrated sulfuric acid dosing pump in combination with the maximum single dosage of the concentrated sulfuric acid dosing pump;

[0092] A frequency difference determination unit is used to set an open-loop control scheme for performing open-loop control on the concentrated sulfuric acid dosing pump according to the real-time frequency at the initial moment, and compare the real-time frequency required by the concentrated sulfuric acid dosing pump at each moment with the frequency at the previous moment to determine whether there is a frequency difference;

[0093] The open-loop control unit is used to adjust the open-loop control scheme corresponding to the previous moment according to the corresponding frequency difference when there is a frequency difference, and to perform open-loop control on the concentrated sulfuric acid dosing pump according to the adjusted open-loop control scheme.

[0094] In this embodiment, the total dosage refers to the total dosage that the concentrated sulfuric acid dosing pump needs to add to the clarification area of ​​the machine-adding pool per unit time. The total dosage per unit time divided by the maximum single dosage of the concentrated sulfuric acid dosing pump is the real-time frequency required by the concentrated sulfuric acid dosing pump.

[0095] In this embodiment, the open-loop control scheme includes the dosing frequency of the concentrated sulfuric acid dosing pump and the corresponding time, and the frequency difference is used to determine whether the open-loop control scheme needs to be adjusted.

[0096] The beneficial effect of the above technical solution is: the required dosage per unit time is determined by the concentrated sulfuric acid flow rate at the corresponding moment and the first deviation value, and the frequency of the concentrated sulfuric acid dosing pump is determined in combination with the maximum single dosage of the concentrated sulfuric acid dosing pump, thereby ensuring the accuracy of the dosing pump frequency at each moment, setting an open-loop control scheme and judging whether the open-loop control scheme needs to be adjusted based on the frequency difference, which can ensure the stability of the open-loop control scheme to the greatest extent.

[0097] The embodiment of the present invention provides an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water, and a closed-loop control module, including:

[0098] A first total amount determination unit is used to obtain the duration of open-loop control of the concentrated sulfuric acid dosing pump and the historical open-loop control scheme, and determine the first total amount of concentrated sulfuric acid entering the clarification area of ​​the machine-adding tank within the corresponding time period based on the historical open-loop control scheme;

[0099] The second total amount determination unit is used to obtain the real-time flow rate between the clarification area of ​​the machine-added pool and the variable porosity filter in the corresponding time period, and determine the total amount of the second concentrated sulfuric acid flowing into the variable porosity filter in the corresponding time period based on the total amount of the first concentrated sulfuric acid entering the clarification area of ​​the machine-added pool;

[0100] The third value acquisition unit is used to obtain the total flow difference of the variable pore filter in the corresponding time period, and obtain the third real-time pH value of the variable pore filter at the corresponding time based on the total flow difference, the first real-time pH value of the variable pore filter at the initial time and the second total amount of concentrated sulfuric acid.

[0101] In this embodiment, the historical open-loop control scheme refers to the control scheme from the beginning of controlling the concentrated sulfuric acid dosing pump to the present moment. The first total amount of concentrated sulfuric acid entering the clarification area of ​​the mechanical treatment tank can be obtained through the historical open-loop control scheme.

[0102] In this embodiment, the total amount of second concentrated sulfuric acid entering the variable pore filter from the start of open-loop control to the current moment can be determined through the real-time flow of the machine-processed tank clarification area and the variable pore filter in the corresponding time period and the total amount of the first concentrated sulfuric acid entering the machine-processed tank clarification area at the corresponding moment.

[0103] In this embodiment, the total flow difference of the variable pore filter in the corresponding time period refers to the difference between the total flow flowing into the variable pore filter from the clarification zone of the machine-added tank after the variable pore filter starts to perform open-loop control and the total flow flowing out of the variable pore filter.

[0104] The beneficial effects of the above technical solution are: by obtaining the duration of open-loop control of the concentrated sulfuric acid dosing pump and the historical open-loop control scheme, the first total amount of concentrated sulfuric acid flowing into the clarification area of ​​the machine-processing tank after open-loop control is obtained, and the second total amount of concentrated sulfuric acid entering the variable-pore filter is obtained through the flow of the clarification area of ​​the machine-processing tank and the variable-pore filter, thereby ensuring the accuracy of the total amount of concentrated sulfuric acid entering the variable-pore filter, and obtaining the third real-time pH value by obtaining the total flow difference of the variable-pore filter and calculating it, thereby ensuring the matching of the third real-time pH value with the historical open-loop control scheme.

[0105] The embodiment of the present invention provides an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water, and a closed-loop control module, including:

[0106] A to-be-adjusted value determination unit, configured to compare the third real-time pH value of the variable pore filter with the first real-time pH value at the corresponding moment to obtain a pH difference, and determine the to-be-adjusted pH value of the corresponding machine-added tank clarification zone based on the pH difference;

[0107] The adjusted amount determining unit is used to determine the required amount of concentrated sulfuric acid flow in the machining pool clarification zone based on the pH value to be adjusted in the machining pool clarification zone and the flow difference in the machining pool clarification zone at the corresponding time, and determine the adjusted amount based on the amount to be adjusted;

[0108] The closed-loop control unit is used to determine a closed-loop control scheme based on the regulated amount and the first deviation value at the corresponding moment, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the closed-loop control scheme.

[0109] In this embodiment, the pH difference is actually the difference between the calculated value and the actual value of the variable pore filter. The pH difference is proportional to the pH value to be adjusted in the clarification zone of the machine-processed pool. The higher the absolute value of the pH difference, the higher the absolute value of the pH value to be adjusted.

[0110] In this embodiment, the amount to be adjusted refers to the amount to be adjusted of the concentrated sulfuric acid flow rate, and the amount to be adjusted refers to the amount to be adjusted of the dosing frequency of the concentrated sulfuric acid dosing pump.

[0111] In this embodiment, the closed-loop control scheme refers to performing closed-loop control on the concentrated sulfuric acid dosing pump by determining the real-time frequency of the concentrated sulfuric acid dosing pump through the first deviation value between the regulated variable and the corresponding moment.

[0112] The beneficial effect of the above technical scheme is: by comparing the calculated value of the variable pore filter with the actual measured value, and determining the difference of the variable pore filter, and then determining the value to be adjusted in the clarification zone of the machine-added tank according to the difference, determining the pH value to be adjusted by the value to be adjusted and the flow difference, and determining the adjusted amount by the pH value to be adjusted and the flow difference in the clarification zone of the machine-added tank, and then combining the adjusted amount with the first deviation value to determine the closed-loop control scheme to perform closed-loop control on the concentrated sulfuric acid dosing pump, the accuracy of the system is improved and the occurrence of large overshoot is avoided.

[0113] The embodiment of the present invention provides an open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid, wherein the controlled quantity determination unit comprises:

[0114] A coefficient determination block is used to obtain the working environment of the machine-processed pool clarification area and the working parameters under the corresponding working environment, and determine the pH value floating coefficient of the machine-processed pool clarification area under the corresponding working environment based on the working parameters;

[0115]

[0116]

[0117] in, is the pH floating coefficient, is the temperature weight coefficient, is the environmental weight coefficient, n is the number of pH value collections per unit time, is the maximum allowable temperature value, is the minimum allowable temperature value, is the temperature value when the ith pH value is collected, is the actual usage capacity of the clarification area of ​​the pool at the time of pH value collection for the i-th time, The standard usage capacity of the clarification area of ​​the machine pool;

[0118] The ratio comparison block is used to obtain the ratio between multiple pH values ​​to be adjusted in the clarification area of ​​the machine-added pool and the second real-time pH value within a unit time, and compare each ratio with the pH value floating coefficient to determine the comparison coefficient;

[0119]

[0120] Where D1 represents the contrast coefficient; Indicates the number of pH values ​​to be adjusted;

[0121] An adjustment determination block, for when there is a comparison coefficient greater than a preset coefficient and the number satisfies a preset threshold, then there is no need to adjust the concentrated sulfuric acid flow rate;

[0122] Otherwise, the flow rate of concentrated sulfuric acid needs to be adjusted;

[0123] The block for determining the amount to be adjusted is used to obtain the integral of the difference between each second real-time pH value of the clarification zone of the machine-added pool and the pH value to be adjusted within a unit time, and obtain the total flow difference of the clarification zone of the machine-added pool within a unit time, and determine the amount to be adjusted of the required concentrated sulfuric acid flow rate within the corresponding unit time based on the integral of the difference and the total flow difference;

[0124] A block for determining a frequency to be adjusted, for determining the total concentrated sulfuric acid flow rate per unit time of the concentrated sulfuric acid dosing pump after adjustment based on the amount to be adjusted and the concentrated sulfuric acid flow rate required at the corresponding time, and determining the working frequency to be adjusted of the concentrated sulfuric acid dosing pump based on the total concentrated sulfuric acid flow rate;

[0125] The regulated quantity determination block is used to compare the working frequency to be adjusted with the working frequency required by the concentrated sulfuric acid dosing pump at the corresponding moment, and determine the regulated quantity based on the comparison result.

[0126] In this embodiment, the working environment of the machining pool clarification area includes environmental factors such as working temperature and working environment, and the working parameters include parameters such as temperature parameters and environmental parameters.

[0127] In this embodiment, the pH value floating coefficient refers to the range in which the pH value in the clarification zone of the machining pool is allowed to float. For example, if the pH value floating coefficient is 0.3, when the ratio between the pH value to be adjusted in the clarification zone of the machining pool and the second real-time pH value exceeds 0.3, it exceeds the floating range and the pH value to be adjusted needs to be adjusted.

[0128] In this embodiment, the preset threshold refers to the minimum amount by which the ratio between the pH value to be adjusted and the second real-time pH value exceeds the floating range when adjustment is required.

[0129] In this embodiment, the total concentrated sulfuric acid flow rate is the sum of the concentrated sulfuric acid flow rate required at a corresponding moment and the amount to be adjusted at the corresponding moment.

[0130] The beneficial effects of the above technical scheme are: determining the working parameters and the pH value floating coefficient through the working environment of the clarification zone of the machine-processed pool to determine whether adjustment is needed, which greatly improves the work efficiency; obtaining the integral of the difference between the real-time value and the value to be adjusted and the total flow difference in the clarification zone of the machine-processed pool and determining the amount to be adjusted; performing control compensation through integration, thereby improving the accuracy of system operation; determining the total amount through the amount to be adjusted and the concentrated sulfuric acid flow required at the corresponding moment; and determining the working frequency to be adjusted of the concentrated sulfuric acid dosing pump based on the total amount; and comparing the adjusted amount with the working frequency required at the corresponding moment to determine the adjusted amount, thereby ensuring the accuracy of the adjusted amount and further ensuring the accuracy of the closed-loop control scheme.

[0131] 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. An open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water, characterized in that: include: Deviation determination module: used for obtaining a first real-time pH value of the variable pore filter and determining a first deviation value between the first real-time pH value and a set pH value; Flow determination module: used to obtain the second real-time pH value of the clarification zone of the machining pool and the water inlet flow of the machining pool, and determine the required concentrated sulfuric acid flow based on the water inlet flow and the second real-time pH value; An open-loop control module: used to determine the real-time frequency required by the concentrated sulfuric acid dosing pump based on the first deviation value and the required concentrated sulfuric acid flow rate, and perform open-loop control on the concentrated sulfuric acid dosing pump based on the real-time frequency; Closed-loop control module: used to obtain the third real-time pH value of the variable pore filter after the start of open-loop control, and determine the adjusted amount based on the difference between the third real-time pH value and the first real-time pH value, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the adjusted amount and the first deviation value at the corresponding time; Among them, the closed-loop control module includes: A to-be-adjusted value determination unit, configured to compare the third real-time pH value of the variable pore filter with the first real-time pH value at the corresponding moment to obtain a pH difference, and determine the to-be-adjusted pH value of the corresponding machine-added tank clarification zone based on the pH difference; The adjusted amount determining unit is used to determine the required amount of concentrated sulfuric acid flow in the machining pool clarification zone based on the pH value to be adjusted in the machining pool clarification zone and the flow difference in the machining pool clarification zone at the corresponding time, and determine the adjusted amount based on the amount to be adjusted; A closed-loop control unit, used to determine a closed-loop control scheme based on the regulated amount and a first deviation value at a corresponding moment, and perform closed-loop control on the concentrated sulfuric acid dosing pump based on the closed-loop control scheme; Wherein, the controlled variable determination unit includes: A coefficient determination block is used to obtain the working environment of the machine-processed pool clarification area and the working parameters under the corresponding working environment, and determine the pH value floating coefficient of the machine-processed pool clarification area under the corresponding working environment based on the working parameters; in, is the pH floating coefficient, is the temperature weight coefficient, is the environmental weight coefficient, n is the number of pH value collections per unit time, is the maximum allowable temperature value, is the minimum allowable temperature value, is the temperature value when the ith pH value is collected, is the actual usage capacity of the clarification area of ​​the pool at the time of pH value collection for the i-th time, The standard usage capacity of the clarification area of ​​the machine pool; The ratio comparison block is used to obtain the ratio between multiple pH values ​​to be adjusted in the clarification area of ​​the machine-added pool and the second real-time pH value within a unit time, and compare each ratio with the pH value floating coefficient to determine the comparison coefficient; Where D1 represents the contrast coefficient; Indicates the number of pH values ​​to be adjusted; An adjustment determination block, for when there is a comparison coefficient greater than a preset coefficient and the number satisfies a preset threshold, then there is no need to adjust the concentrated sulfuric acid flow rate; Otherwise, the flow rate of concentrated sulfuric acid needs to be adjusted; The block for determining the amount to be adjusted is used to obtain the integral of the difference between each second real-time pH value of the clarification zone of the machine-added pool and the pH value to be adjusted within a unit time, and obtain the total flow difference of the clarification zone of the machine-added pool within a unit time, and determine the amount to be adjusted of the required concentrated sulfuric acid flow rate within the corresponding unit time based on the integral of the difference and the total flow difference; A block for determining a frequency to be adjusted, for determining the total concentrated sulfuric acid flow rate per unit time of the concentrated sulfuric acid dosing pump after adjustment based on the amount to be adjusted and the concentrated sulfuric acid flow rate required at the corresponding moment, and determining the working frequency to be adjusted of the concentrated sulfuric acid dosing pump based on the total concentrated sulfuric acid flow rate; The controlled quantity determination block is used to compare the working frequency to be adjusted with the working frequency required by the concentrated sulfuric acid dosing pump at the corresponding moment, and determine the controlled quantity based on the comparison result.

2. The open-loop and closed-loop controlled automatic dosing control system for reclaimed sulfuric acid water according to claim 1 is characterized in that: Deviation determination module, including: A first value acquisition unit is used to establish a pH real-time monitoring system based on a pH meter to perform real-time monitoring on the variable pore filter to be monitored, and determine a first real-time pH value of the variable pore filter; The deviation determination unit is used to obtain the working requirements of the variable pore filter, determine the set pH value of the variable pore filter at the corresponding time based on the working requirements, and determine a first deviation value between the first real-time pH value and the set pH value at the corresponding time.

3. The open-loop and closed-loop controlled automatic dosing control system for reclaimed sulfuric acid water according to claim 2 is characterized in that: The flow determination module includes: A second value acquisition unit is used to perform real-time monitoring on the clarification area of ​​the machine-processing tank based on the real-time monitoring system to determine a second real-time pH value of the clarification area of ​​the machine-processing tank; The flow determination unit is used to obtain the water inlet hole size and water inlet flow rate of the machining pool, and calculate the water inlet flow of the corresponding machining pool.

4. The open-loop and closed-loop controlled automatic dosing control system for reclaimed sulfuric acid water according to claim 3 is characterized in that: The flow determination module includes: A machine-processing tank content determination unit, used to obtain a first real-time capacity of a clarification zone of the machine-processing tank, and determine the concentrated sulfuric acid content of the clarification zone of the machine-processing tank at a corresponding time based on the first real-time capacity and the second real-time pH value; a required amount determination unit, configured to obtain a second real-time capacity of the variable porosity filter, and determine a real-time concentrated sulfuric acid amount required for the variable porosity filter based on the second real-time capacity and the first deviation value; A flow difference determination unit, used to obtain the real-time flow rate between the clarification area of ​​the machine-processing tank and the variable-pore filter tank, and to obtain the flow difference of the clarification area of ​​the machine-processing tank based on the real-time flow rate and the inflow flow rate of the machine-processing tank; The flow determination unit is used to determine the real-time concentrated sulfuric acid content required in the clarification zone of the machining pool based on the flow difference and the real-time concentrated sulfuric acid amount required by the variable pore filter, and to determine the concentrated sulfuric acid flow required in the clarification zone of the machining pool in combination with the water inlet flow of the machining pool.

5. The open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water according to claim 4 is characterized in that: Open-loop control module, including: A frequency determination unit, for determining the total dosage required per unit time of the concentrated sulfuric acid dosing pump based on the concentrated sulfuric acid flow required at the corresponding moment and the first deviation value, and determining the real-time frequency required by the concentrated sulfuric acid dosing pump in combination with the maximum single dosage of the concentrated sulfuric acid dosing pump; A frequency difference determination unit is used to set an open-loop control scheme for performing open-loop control on the concentrated sulfuric acid dosing pump according to the real-time frequency at the initial moment, and compare the real-time frequency required by the concentrated sulfuric acid dosing pump at each moment with the frequency at the previous moment to determine whether there is a frequency difference; The open-loop control unit is used to adjust the open-loop control scheme corresponding to the previous moment according to the corresponding frequency difference when there is a frequency difference, and to perform open-loop control on the concentrated sulfuric acid dosing pump according to the adjusted open-loop control scheme.

6. The open-loop and closed-loop composite control system for automatic dosing of reclaimed sulfuric acid water according to claim 1 is characterized in that: Closed-loop control module, including: A first total amount determination unit is used to obtain the duration of open-loop control of the concentrated sulfuric acid dosing pump and the historical open-loop control scheme, and determine the first total amount of concentrated sulfuric acid entering the clarification area of ​​the machine-adding tank in the corresponding time period based on the historical open-loop control scheme; The second total amount determination unit is used to obtain the real-time flow rate between the clarification area of ​​the machine-added pool and the variable porosity filter in the corresponding time period, and determine the total amount of the second concentrated sulfuric acid flowing into the variable porosity filter in the corresponding time period based on the total amount of concentrated sulfuric acid entering the clarification area of ​​the machine-added pool; The third value acquisition unit is used to obtain the total flow difference of the variable pore filter in the corresponding time period, and obtain the third real-time pH value of the variable pore filter at the corresponding time based on the total flow difference, the first real-time pH value of the variable pore filter at the initial time and the second total amount of concentrated sulfuric acid.

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