CN106277299B - Aeration control system and method based on oxygen consumption rate tester - Google Patents

Aeration control system and method based on oxygen consumption rate tester Download PDF

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CN106277299B
CN106277299B CN201610757777.1A CN201610757777A CN106277299B CN 106277299 B CN106277299 B CN 106277299B CN 201610757777 A CN201610757777 A CN 201610757777A CN 106277299 B CN106277299 B CN 106277299B
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aeration
dissolved oxygen
value
oxygen
actual
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CN106277299A (en
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罗涛
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Shine Beijing Water Co ltd
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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/02—Aerobic processes
    • C02F3/12—Activated sludge processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/005—Processes using a programmable logic controller [PLC]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/22—O2
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Abstract

The invention discloses an aeration control system which comprises a data acquisition unit, a P L C control unit and an aeration unit, wherein the data acquisition unit comprises an OUR tester and a DO tester, the aeration unit comprises an air blower, a micropore aeration head and a flow meter, the P L C control unit comprises hardware such as a control cabinet, a display screen and the like and control software, and the control software comprises a control unit based on an OUR value, an OTE value and a dissolved oxygen value and a protection unit based on DO feedback.

Description

Aeration control system and method based on oxygen consumption rate tester
Technical Field
The invention relates to the field of sewage treatment, in particular to an aeration control system and method based on an oxygen consumption rate tester.
Background
In the industrial development and energy utilization of China at the present stage, energy conservation and emission reduction are still important subjects. Currently, the current practice is. The energy efficiency of urban sewage treatment in China is still at a low stage, and the high energy consumption per ton of water is still high; as is well known, the sewage treatment industry is a high-energy-consumption industry, the total power consumption of the sewage treatment industry in 2012 in China is up to 125 hundred million kWh, and the unit power consumption is 0.29kWh/m3If the price of the electric charge is 0.7 yuan/kWh, the total electric charge is nearly 90 million yuan, and at present, a large part of sewage plants in China have no sludge treatment facilities. Along with the implementation of upgrading and reconstruction in various regions, the energy consumption of sewage treatment in China is further increased. Therefore, energy conservation and consumption reduction are important tasks of the operation management of the sewage treatment plant in China at present.
The aeration system is an important part in the sewage biological treatment process, is mainly used for supplying oxygen to an oxygen consumption tank, and is also the most important energy consumption link. Generally, the total power consumption of the sewage plant is about 50% -70%, so that the energy consumption in the aeration stage is reduced, which is the important factor for saving energy and reducing consumption of the sewage plant. The aeration control strategy is to realize automatic and accurate regulation and control of aeration quantity in the sewage treatment process by adopting an automatic control instrument and instrument so as to achieve the purposes of stable effluent quality reaching the standard, energy conservation, consumption reduction and personnel intervention reduction.
At present, the most common domestic aeration control method is a relatively extensive manual debugging mode, aeration quantity is usually determined according to the experience of operators, and if the effluent quality does not fluctuate obviously for a long time, the aeration quantity cannot be adjusted in real time; once the operation condition is changed, the adjustment of the aeration amount is still only adjusted according to the experience, so that the problems of insufficient aeration or excessive aeration are caused, even the aeration system of some treatment plants is operated for a long time in a state of exceeding the normal load, the quality of effluent water is not ensured, and a large amount of energy consumption waste is caused. Most control strategies do not relate to the mass transfer efficiency of oxygen, and the relationship between the aeration rate and the conversion rate cannot be accurately grasped, so that the control of the aeration rate is inaccurate.
At present, for a system which carries out aeration control by using ORP (oxidation-reduction potential) and pH, the actual application is not wide because the ORP and the pH have no direct linear relation with aeration quantity, the ORP value is delayed seriously in a short period, and the accurate judgment is difficult in the nitrification-denitrification process. The water quality index is used as feedforward aeration control, the basic principle is to calculate the oxygen amount required to be provided through the pollutant concentration, but the sewage quality index is mostly determined by experiments, the determination time needs hours or even days, and the effect on real-time control is not great. The on-line water quality detecting instrument has delay of hours, and is expensive and not completely popularized.
The intermittent aeration is realized by repeatedly starting and stopping the blower, so that the oxygen consumption tank is in an alternative state of aeration and non-aeration, the intermittent aeration is simple and practical, the control performance is unstable, the blower is generally in the maximum load, the energy consumption is high, the service life of the blower can be shortened, and the control of aeration amount with large difference can also reduce the aeration precision. Therefore, it is desirable to provide a precise and reliable aeration control method.
Disclosure of Invention
The invention aims to provide an aeration control system and method, which can realize accurate aeration and achieve the purposes of energy conservation and consumption reduction.
The application provides an aeration control system, which comprises a data acquisition unit, a P L C control unit and an aeration unit, wherein the data acquisition unit comprises an oxygen consumption rate determinator and a dissolved oxygen determinator, the aeration unit comprises a blower, a microporous aeration head and a flowmeter, the P L C control unit comprises a control cabinet and a display screen, control software is arranged in the control cabinet, and the control software comprises a control unit based on an oxygen consumption rate value and a dissolved oxygen value and a protection unit fed back by DO;
the detection part of the oxygen consumption rate measuring instrument extends into the aeration tank, and the oxygen consumption rate measuring instrument is in signal connection with the P L C control unit;
the detection part of the dissolved oxygen tester extends into the aeration tank, and the dissolved oxygen tester is in signal connection with the P L C control unit;
the microporous aeration head is arranged in an aeration tank, an inlet of the microporous aeration head is communicated with the air blower, the flow meter is arranged on a pipeline between the microporous aeration head and the air blower, and the flow meter and the air blower are both connected with a P L C control unit.
Preferably, the aeration control system further comprises a stirring device, and one end of the stirring device is arranged in the aeration tank.
The application also provides a method for controlling aeration by using the aeration control system, which comprises the following steps:
inputting a dissolved oxygen setpoint in the P L C control unit;
detecting actual dissolved oxygen concentration, if the dissolved oxygen set value-actual dissolved oxygen value is greater than k1, and adjusting the aeration amount in the aeration tank according to DO feedback;
if the | dissolved oxygen set value-actual dissolved oxygen value | is less than or equal to k1, calculating the aeration amount required by the dissolved oxygen set value by the P L C control unit according to the detected sludge oxygen consumption rate, the actual dissolved oxygen concentration and the calculated oxygen transfer efficiency, wherein the oxygen transfer efficiency is calculated by the P L C control unit according to the sludge oxygen consumption rate, and the k1 is 0.3-0.5 mg/L;
and adjusting the air blower according to the aeration amount to control the aeration amount in the aeration tank.
Preferably, if the actual dissolved oxygen value is less than the dissolved oxygen set value, (-) dissolved oxygen set value — actual dissolved oxygen value, (-) k1, the change coefficient β is increased in proportion to the previous aeration amount (C)Set value-CActual value) When the actual dissolved oxygen value is larger than the dissolved oxygen set value, the subtraction of the change coefficient β based on the last aeration amount is proportional to (C)Actual value-CSet value) Value of β > 0, and according to exposureThe specific conditions of the air pool are adjusted.
Preferably, the sludge oxygen consumption rate is measured on line by an oxygen consumption rate measuring instrument, and the period of the on-line measurement is 15 min.
Preferably, the actual dissolved oxygen concentration is monitored in real time by a dissolved oxygen monitor, and the oxygen transfer rate is calculated from the oxygen consumption rate and the last aeration amount.
Preferably, the calculation formula of the aeration amount required for obtaining the dissolved oxygen set value is:
Figure GDA0002253994290000031
wherein Q is the required aeration quantity, OUR is the oxygen consumption rate of the activated sludge, VAeration tankIs the volume of the aeration tank, tControl periodThe time required for determining a value for the OUR instrument, CSet valueTo control the target dissolved oxygen concentration to be achieved after the reaction, CActual valueDetermining the dissolved oxygen concentration for the actual dissolved oxygen probe;
SOTR is the fresh water oxygenation capacity of the aerator under the quantity of Q gas and is saturated dissolved oxygen under the standard state, k is a correction parameter of the saturated dissolved oxygen, SOTE is the oxygen utilization rate of the aerator under the standard state,
Figure GDA0002253994290000032
is the saturated dissolved oxygen concentration under standard conditions.
The invention provides an aeration control system, which comprises a data acquisition unit, a P L C control unit and an aeration unit, wherein the data acquisition unit comprises an oxygen consumption rate (OUR) determinator and a Dissolved Oxygen (DO) determinator, the aeration unit comprises a blower, a micropore aeration head and a flow meter, the aeration control system is based on the OUR as a control parameter, the control system timely adjusts the aeration amount by measuring the real-time oxygen consumption of activated sludge in an aeration tank to provide accurate basis for the oxygen amount which should be supplied by the aeration system, the accurate control of the aeration amount is further realized by measuring the oxygen consumption rate of the aeration control system, meanwhile, the aeration amount which needs to be supplied is accurately adjusted by measuring the oxygen consumption rate of the aeration control system through the difference between the actual dissolved oxygen concentration and the dissolved oxygen concentration set value, so that the adjustment range of the aeration amount is reduced, namely, the accurate control of the aeration amount is further realized, the absolute value of the difference between the actual dissolved oxygen concentration and the determined value is used for accurately adjusting the aeration amount, if the absolute value of the difference between the actual dissolved oxygen concentration and the determined value is greater than 1, the absolute value of the DO is used for directly adjusting the aeration amount, the DO 1, the DO is used for realizing the purposes of automatic control of the automatic acquisition of the DO collection and the calculation, the control of the energy-saving and the control of the output of the energy.
Drawings
FIG. 1 is a schematic view of the structure of an aeration control system according to the present invention;
FIG. 2 is a flow chart of an embodiment of the aeration control method of the present invention.
Detailed Description
For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims.
The embodiment of the invention discloses an aeration control system, which comprises a data acquisition unit, a P L C control unit and an aeration unit, wherein the data acquisition unit comprises an oxygen consumption rate determinator and a dissolved oxygen determinator;
a breathing pipe of the oxygen consumption rate tester extends into the aeration tank, and the oxygen consumption rate tester is in signal connection with the P L C control unit;
the probe of the dissolved oxygen tester is immersed in the aeration tank, and the dissolved oxygen tester is in signal connection with the P L C control unit;
the micropore aeration head is arranged at the bottom of the aeration tank, a ventilation pipeline of the micropore aeration head is communicated with the air blower, the flow meter is arranged on a pipeline between the micropore aeration head and the air blower, and the flow meter and the air blower are both connected with the P L C control unit.
The control unit of P L C is mainly provided with a DO feedback protection unit besides a control unit based on OUR value and dissolved oxygen value, and the control units can be directly input by the technicians in the field, and the application is not limited in particular.
The DO feedback protection unit is activated when dissolved oxygen concentration fluctuations (absolute value of difference between actual dissolved oxygen concentration and dissolved oxygen set point) exceed k1, while the OUR based aeration control system is deactivated.
As shown in fig. 1, fig. 1 is a schematic structural diagram of an aeration control system of the present invention, in which 1 is an aeration tank, 2 is a Dissolved Oxygen (DO) real-time monitor, 3 is a sludge oxygen consumption rate (OUR) meter, 4 is a stirring device, 5 is a programmable logic control unit (P L C), 6 is an aeration pipeline, 7 is a data signal transmission line, 8 is a blower, 9 is a flow meter, and 10 is a microporous aeration head.
In order to make the oxygen distribution in the aeration tank uniform, the aeration control system further comprises a stirring device 4, and one end of the stirring device 4 is arranged in the aeration tank. Microporous aeration head 11 increases the specific surface area of the air bubbles, thereby increasing the transfer efficiency of oxygen.
The aeration tank, the sludge oxygen consumption rate determinator, the stirring device, the dissolved oxygen real-time monitor, the flow meter, the aeration pipeline, the blower, the data signal transmission line and the microporous aeration head are all devices well known to those skilled in the art, and the sources of the devices are not particularly limited in the present application. The OUR determinator is used for detecting the oxygen consumption rate of activated sludge in an aeration tank, and the DO determinator is used for monitoring the dissolved oxygen amount of the aeration tank in real time.
The P L C control system is a control system well known to those skilled in the art, and includes a data acquisition end, a data display window and system automatic control software.
The OUR tester and the DO tester respectively test the OUR value and the DO value in the aeration tank; wherein the oxygen consumption rate (OUR) refers to the speed of oxygen consumed by microorganisms in the sludge during respiration by utilizing organic matters, is an important index for representing the activity of the microorganisms in the sludge and represents the actual oxygen demand.
The aeration control system firstly judges the difference value between the DO actual value and the DO set value according to the OUR value and the DO value automatically collected on line through the P L C control unit, if the difference value is larger, the aeration quantity is firstly adjusted, if the difference value is smaller, the aeration quantity required to be supplied is automatically calculated according to a formula, and then the signal is output to change the blast flow, so that the accuracy of aeration control is ensured.
Inputting a dissolved oxygen setpoint in the P L C control unit;
detecting actual dissolved oxygen concentration, if the dissolved oxygen set value-actual dissolved oxygen value is greater than k1, and adjusting the aeration amount in the aeration tank according to DO feedback;
if the | dissolved oxygen set value-actual dissolved oxygen value | is less than or equal to k1, calculating the aeration amount required by the dissolved oxygen set value by the P L C control unit according to the detected sludge oxygen consumption rate, the actual dissolved oxygen concentration and the calculated oxygen transfer efficiency, wherein the oxygen transfer efficiency is calculated by the P L C control unit according to the sludge oxygen consumption rate, and the k1 is 0.3-0.5 mg/L;
and adjusting the air blower according to the aeration amount to control the aeration amount in the aeration tank.
The process comprises the following steps:
inputting a dissolved oxygen setpoint in the P L C control unit;
detecting actual dissolved oxygen concentration, if the dissolved oxygen set value-actual dissolved oxygen value | k1, and adjusting the aeration amount according to DO feedback;
detecting actual dissolved oxygen concentration, if an agent dissolved oxygen set value-actual dissolved oxygen value agent is not more than k1, calculating by a P L C control unit according to the detected sludge oxygen consumption rate and the actual dissolved oxygen concentration to obtain actual instantaneous oxygen supply, and calculating by a P L C control unit according to actual aeration parameters and oxygen transfer efficiency to obtain aeration system performance evaluation parameters, wherein the oxygen transfer efficiency is calculated by a P L C control unit according to the sludge oxygen consumption rate;
calculating by a P L C control unit according to the actual instantaneous oxygen supply amount, the dissolved oxygen set value and the performance evaluation parameter of the aeration system to obtain the aeration amount required by the dissolved oxygen set value;
and adjusting the air blower according to the aeration amount to control the aeration amount in the aeration tank.
Specifically, if the actual dissolved oxygen value is higher or lower than a set value and exceeds k1, the DO feedback protection unit is started, the actual dissolved oxygen is rapidly approached to the set value by reducing or increasing the aeration amount, when the difference between the actual dissolved oxygen and the set value is less than or equal to k1, the DO feedback protection unit is closed, and the aeration amount is calculated, the k1 is determined according to the actual condition of an oxygen consumption tank and ranges from 0.3 mg/L, and can be adjusted within the range according to the specific condition of the aeration tank, and the process is shown in figure 2.
Firstly, inputting a dissolved oxygen set value into a P L C control unit, detecting an actual dissolved oxygen concentration, adjusting the aeration amount in an aeration tank if | the dissolved oxygen set value-the actual dissolved oxygen value | is > k1, and particularly CSet value-CActual valueWhen the aeration rate is more than k1, the change coefficient β is increased based on the last aeration rate to be proportional to (C)Set value-CActual value) A value of (d); at CActual value-CSet valueWhen the aeration rate is more than k1, the subtraction of the change coefficient β on the basis of the last aeration rate is proportional to (C)Actual value-CSet value) Thereby realizing that the fluctuation range is reduced by rapidly increasing or decreasing the air quantity in time when the fluctuation range exceeds +/-k 1, the change coefficient β is more than 0, and the aeration tank is subjected to specific conditionsAnd then the adjustment is made.
This algorithm, | CSet value-CActual value︱>k1 is enabled.
After the adjustment, if the difference between the DO actual value and the DO set value is still larger than k1, DO feedback adjustment of aeration amount is continued, and if the difference is smaller than k1, OUR-based aeration control is performed. According to the invention, the system is operated continuously, the sequence of the DO feedback protection and the accurate algorithm based on the OUR measured value is not limited, namely, the control method provided by the application is a conditional control method.
The process of utilizing the aeration control system to carry out aeration control comprises the steps of inputting an expected DO value into software in a P L C control unit, inputting an initial aeration amount, measuring an OUR value according to an oxygen consumption rate (OUR) measuring instrument, calculating an Oxygen Transfer Efficiency (OTE) value according to the relation of parameters such as oxygen transfer rate (OTE) and OUR, calculating required actual aeration amount according to a function formula of the relation between the actual aeration amount and other parameters, and adjusting a fan according to the aeration amount.
In the process, the sludge oxygen consumption rate is measured by an active sludge oxygen consumption rate on-line measuring device, and the time interval of the measuring device is 15 min; and the actual dissolved oxygen concentration is detected by a dissolved oxygen real-time monitor.
The performance evaluation parameters of the aeration system are important indexes of comprehensive oxygenation performance of aeration in a process state and are obtained by an online measuring device and actual aeration parameters, wherein the actual aeration parameters comprise the oxygenation capacity of clear water of an aerator, correction parameters based on basic conditions of water quality and saturated dissolved oxygen concentration in a standard state; the actual aeration rate is measured by a flowmeter.
The calculation process is controlled by P L C.
Firstly, calculating the actual instantaneous oxygen supply amount according to the following formula:
Figure GDA0002253994290000081
wherein OUR is the oxygen consumption rate of the activated sludge, VAeration tankIs the volume of the aeration tank, tControl periodDetermination of the period, C, for the OUR InstrumentSet valueTo adjust the target value to be achieved, CActual valueIs the actual measured value of the dissolved oxygen probe; among the above parameters, VAeration tank、CSet value、tControl periodFor the preset parameters, OUR and CActual valueIs an instrumental measurement value; the oxygen supply amount can be calculated according to the calculation formula and the measured value of the instrument.
And then, calculating the performance evaluation parameters of the aeration system, wherein the calculation formula is as follows:
Figure GDA0002253994290000082
wherein Q is the required aeration quantity, SOTR is the pure water oxygenation capacity of the aerator under the quantity of Q, and is saturated dissolved oxygen under a standard state, and k is a correction parameter of the saturated dissolved oxygen; theta is a temperature correction parameter of the oxygen transfer efficiency; among the above parameters, CActual valueSOTR, k and theta are set values for the measured value of the instrument, wherein: theta is 0.888.
The SOTR changes along with the change of aeration quantity, the k changes along with the change of water quality, the temperature and the position of a test site, and therefore the parameter k is a variable. In contrast, SOTR can be obtained from specification of performance index of aerator products used in sewage treatment plants, and k can be determined by first determining saturated dissolved oxygen in sewage and by measuring atmospheric pressure on site, and then defaulted to a fixed value. In the process of calculating the performance evaluation parameters of the aeration system, Q is the required aeration quantity, and specifically comprises the following steps: if the aeration system is started for the first time, Q is the set aeration quantity, if the aeration system is operated for a period of time, Q is the aeration quantity calculated last time, and in the process, in order to distinguish the last aeration quantity from the actual aeration quantity, the last calculation value of the actually measured aeration quantity is set as Q1.
In the above formula, the OTE is calculated by its relationship with other parameters, and the Oxygen Transfer Efficiency (OTE) is performed according to the following rule:
Figure GDA0002253994290000091
wherein OT is the consumption of oxygen in the aeration tank, OS is the air supply, OUR is the oxygen consumption rate of the activated sludge, VAeration tankQ1 is the last calculation value of the aeration amount actually measured for the aeration tank volume.
Substituting the OTE calculation formula into the formula of the aeration system performance evaluation parameter to obtain the aeration system performance evaluation parameter.
And finally, calculating the aeration rate according to the following rules:
Figure GDA0002253994290000092
wherein SOTE is the oxygen utilization rate of the aerator in a standard state.
Brought above AORGeneral assemblyAnd α F, the calculation formula for obtaining the actually required aeration quantity Q is as follows:
Figure GDA0002253994290000093
wherein Q is the required aeration quantity, OUR is the oxygen consumption rate of the activated sludge, VAeration tankIs the volume of the aeration tank, tControl periodDetermination of the period, C, for the OUR InstrumentSet valueIn order to achieve the target value after regulation, the actual value C is the actual measured value of the dissolved oxygen probe, SOTR is the oxygenation capacity of clear water of the aerator under the quantity of Q gas and is saturated dissolved oxygen under the standard state, and k is a correction parameter of the saturated dissolved oxygen; among the above parameters, VAeration tank、CSet value、tControl periodSOTR, k are preset parameters, OUR and CActual valueOTE is the calculated value for instrumental measurements. k varies with the change of the test conditions such as water quality and pressure, but k can be used for measuring the saturated dissolved oxygen in the sewage and the field atmospheric pressureDefault to a constant value. In the calculation of the aeration amount, Q1 is the last calculation value of the actually measured aeration amount. Substituting the OTE calculation formula into the Q formula to obtain the calculation formula of the actually required aeration Q as follows:
Figure GDA0002253994290000094
the aeration control method utilizes the aeration control system to carry out real-time monitoring and calculation on aeration quantity, in the actual aeration control process, the aeration quantity changes in real time along with the change of an on-line monitoring value and the parameters, and the aeration quantity is directly output by the P L C control unit to control the aeration unit.
This algorithm, | CSet value-CActual value| k 1.
The invention utilizes the aeration control system to carry out the aeration control process, which comprises the following steps:
when the actual dissolved oxygen value is not equal to the set value, the P L C recalculates the air volume according to the parameters of the sludge oxygen consumption rate, the oxygen transfer efficiency and the like, and adjusts the fan or increases the aeration volume or decreases the aeration volume so that the actual dissolved oxygen slightly fluctuates above and below the set value;
under the condition that the sludge oxygen consumption rate fluctuates greatly, the activity of the sludge is shown to be in an unconventional state, and the aeration rate can change greatly to adapt to the current life state of the sludge;
when the actual dissolved oxygen value variation trend fluctuates around a set value and the fluctuation is less than k1, the stable control of aeration can be judged to be realized;
when the actual dissolved oxygen value fluctuates beyond k1, the DO protection system is activated at this point.
The application also provides a method for controlling aeration by using the aeration control system, wherein the automatic control software of the system calculates the aeration amount to be supplied together by inputting an automatic control algorithm according to the OUR value and the DO value which are automatically collected on line and the variable OTE value calculated according to the OUR value and the aeration amount, then changes the blast flow by outputting signals, ensures that the DO is stabilized at a set value, has a deviation not exceeding +/-k 1, and if the DO value deviation exceeds +/-k 1 or even is larger, the DO is too low at the moment and can influence the effluent water quality, and if the DO value deviation is too high, the DO indicates that the power consumption is wasted due to excessive aeration, and at the moment, the protection system can be started. Finally, the dynamic balance of oxygen supply and demand is realized, the problem of poor effluent quality caused by insufficient oxygen supply can be solved, and energy waste caused by excessive aeration can be reduced.
According to the aeration control system, the accurate aeration algorithm based on OUR and the DO feedback protection module are combined, so that not only can the sludge activity be accurately monitored and the aeration amount be accurately controlled, but also the problem that dissolved oxygen is too high or too low for a long time when the system is in a problem can be solved, and the purposes of long-term stable effluent quality, energy conservation and consumption reduction are achieved.
For further understanding of the present invention, the aeration control system and the aeration control method provided by the present invention are described in detail below with reference to the following examples, and the scope of the present invention is not limited by the following examples.
Example 1
Setting a desired dissolved oxygen concentration, wherein the set dissolved oxygen value is that the actual aeration quantity is close to or consistent with the desired value as much as possible by changing the aeration quantity;
firstly, writing a control algorithm program in the specification into a P L C control unit 5, after an aeration control system starts to operate, measuring the DO concentration in sewage in real time by a Dissolved Oxygen (DO) measuring instrument 2, sending the DO to the P L C control unit 5 through a data signal transmission line 7, feeding data back to the P L C control unit 5 by an OUR measuring instrument 3, sending an air volume signal to the P L C control unit 5 in real time by a flowmeter 9 through the data signal transmission line 7, calculating the required aeration volume by the P L C control unit through algorithm integration, sending the calculation result to a control blower 8 in a signal mode, and outputting the air volume to an aeration tank 1 through an air pipeline.
The method comprises the following specific working steps of sucking measured mixed liquid 1L, aerating to ensure that DO concentration reaches 6-8 mg/L, pumping the mixed liquid into a respiratory chamber, automatically making a DO time-varying curve by a software program and obtaining the slope k of the curve, namely the OUR value of active microorganisms in the activated sludge, wherein the sample measuring time interval of the OUR measuring instrument 3 is 15min, and a P L C control unit 5 calculates to obtain the required aeration amount according to the OUR value, the measured value of the DO measuring instrument 2 and the OTE calculated value before the next measured value is fed back by the OUR measuring instrument 3;
the OTE calculation formula is input into a P L C control unit 5;
the P L C control unit 5 comprises a data collection module, a command sending module, a data display screen and a historical data module, and judges the quality of the aeration control system by observing the deviation degree of the change trend of the actual dissolved oxygen value and the dissolved oxygen set value.
Example 2
The volume of the aeration tank is 0.25m3Since the measurement period of the OUR measurement apparatus was 15 minutes, the control period was set to 15min, SOTE was 20%, SOTR was 0.03kg/h, k was 0.75, and C was* ∞20Is a saturated dissolved oxygen value at 20 ℃;
the initial setting value of dissolved oxygen is 2, aeration control can be implemented after an OUR tester, a DO tester and an aeration system are all connected into P L C, the OUR tester measures a value every 15min, the DO tester measures in real time, changes of the OUR, OTE and DO values every time are transmitted to a P L C control cabinet through signal transmission lines, actually required air volume is calculated, signals are output to a fan to regulate and control the air volume of the fan, and the numerical value of a flowmeter is displayed and recorded on a P L C display screen through signal lines.
Under the stable condition, the change of the OUR and the OTE values is not large, and the control quality of the dissolved oxygen is stabilized within the range of +/-k 1; if the dissolved oxygen level fluctuates too much due to unpredictable problems, the DO feedback protection system needs to be activated to adjust.
If the OUR value is increased or decreased by a large amount, P L C will transmit the calculated value to the flow controller to command it to make aeration adjustments so that the actual dissolved oxygen quickly returns to a level of 2.
1. DO when OUR is 30 mg/L. hSet valueWhen the oxygen content is 2.0 mg/L, the oxygen DO is actually dissolvedActual valueWhen the Q is 2.0 mg/L, the Q is 7.85L/min;
2. when in useOUR＝30mg/L·h，DOActual valueWhen the ratio of Q to Q is increased to 2.1 mg/L at 2.0 mg/L, the ratio of Q to Q is adjusted to 7.54L/min;
3. if OUR is 30 mg/L. h, k1 is 0.5 mg/LActual valueWhen the flow rate drops to 1.4 mg/L, a DO feedback protection system is started, β is set to 5, the last aeration quantity Q is 8.48L/min, and the Q is adjusted to 11.48L/min.
From 1 to 2, the actual dissolved oxygen exceeds the set value by 2 mg/L, the aeration quantity is correspondingly reduced, so that the actual dissolved oxygen gradually falls back to be closer to the set value, and from 1 to 3, the oxygen is | CSet value-CActual value︱>0.5 mg/L, start the DO feedback protection system, increase the aeration rate, make the actual dissolved oxygen value rise rapidly.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (4)

1. The method for controlling aeration by utilizing the aeration control system comprises the following steps:
the aeration control system comprises a data acquisition unit, a P L C control unit and an aeration unit, wherein the data acquisition unit comprises an oxygen consumption rate tester and a dissolved oxygen tester, the aeration unit comprises an air blower, a micropore aeration head and a flow meter, the P L C control unit comprises a control cabinet and a display screen, control software is arranged in the control cabinet, and the control software comprises a control unit based on an oxygen consumption rate value and a dissolved oxygen value and a protection unit fed back by DO (DO);
the detection part of the oxygen consumption rate measuring instrument extends into the aeration tank, and the oxygen consumption rate measuring instrument is in signal connection with the P L C control unit;
the detection part of the dissolved oxygen tester extends into the aeration tank, and the dissolved oxygen tester is in signal connection with the P L C control unit;
the microporous aeration head is arranged in an aeration tank, the inlet of the microporous aeration head is communicated with the blower, the flow meter is arranged on a pipeline between the microporous aeration head and the blower, and the flow meter and the blower are both connected with a P L C control unit;
inputting a dissolved oxygen setpoint in the P L C control unit;
detecting actual dissolved oxygen concentration, if the dissolved oxygen set value-actual dissolved oxygen value is greater than k1, and adjusting the aeration amount in the aeration tank according to DO feedback;
if the | dissolved oxygen set value-actual dissolved oxygen value | is less than or equal to k1, calculating the aeration amount required by the dissolved oxygen set value by the P L C control unit according to the detected sludge oxygen consumption rate, the actual dissolved oxygen concentration and the calculated oxygen transfer efficiency, wherein the oxygen transfer efficiency is calculated by the P L C control unit according to the sludge oxygen consumption rate, and the k1 is 0.3-0.5 mg/L;
adjusting the blower according to the required aeration amount, and controlling the aeration amount in the aeration tank;
the calculation formula of the aeration amount required by the dissolved oxygen set value is as follows:
Figure 51336DEST_PATH_IMAGE001
wherein Q is the required aeration quantity, OUR is the oxygen consumption rate of the activated sludge, VAeration tankIs the volume of the aeration tank, tControl periodThe time required for determining a value for the OUR instrument, CSet valueTo control the target dissolved oxygen concentration to be achieved after the reaction, CActual valueDetermining the dissolved oxygen concentration for the actual dissolved oxygen probe;
SOTR is the fresh water oxygenation capacity of the aerator under the quantity of Q gas, k is a correction parameter of saturated dissolved oxygen, SOTE is the oxygen utilization rate of the aerator under a standard state,
Figure 787211DEST_PATH_IMAGE002
is the saturated dissolved oxygen concentration under the standard condition;
oxygen Transfer Efficiency (OTE) is performed according to the following rule:
Figure 986111DEST_PATH_IMAGE003
wherein OT is the consumption of oxygen in the aeration tank, OS is the air supply, OUR is the oxygen consumption rate of the activated sludge, VAeration tankQ1 is the last calculation value of the aeration amount actually measured for the aeration tank volume.
2. The method of claim 1, wherein the aeration control system further comprises a stirring device, one end of which is disposed in the aeration tank.
3. The method of claim 1, wherein the addition of a coefficient of variation β on the basis of the last aeration amount is proportional to (C) when the actual dissolved oxygen value is less than the dissolved oxygen set value, > k1, and the dissolved oxygen set value-actual dissolved oxygen value | is greater than k1Set value-CActual value) When the actual dissolved oxygen value is larger than the dissolved oxygen set value, the subtraction of the change coefficient β based on the last aeration amount is proportional to (C)Actual value-CSet value) β > 0 and is adjusted according to the specific conditions of the aeration tank.
4. The method according to claim 1, wherein the sludge oxygen consumption rate is measured on line by an oxygen consumption rate measuring instrument, and the period of the on-line measurement is 15 min.
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CN109775845B (en) * 2017-11-14 2022-02-18 北京天诚同创电气有限公司 Method and device for controlling oxygen exposure in sewage treatment
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1193310A (en) * 1995-06-22 1998-09-16 比萨斯科有限公司 Controlling of wastewater treatment by monitoring oxygen utilisation rates
CN201903539U (en) * 2010-12-03 2011-07-20 北京工业大学 Frequency-converting speed-regulating fast online detecting device for specific oxygen uptake rate
CN102156432A (en) * 2011-02-22 2011-08-17 上海市城市建设设计研究院 Method for controlling aeration in biochemical reaction tank in real time
CN104787872A (en) * 2015-04-29 2015-07-22 梁锐振 Aeration rate control method and system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1193310A (en) * 1995-06-22 1998-09-16 比萨斯科有限公司 Controlling of wastewater treatment by monitoring oxygen utilisation rates
CN201903539U (en) * 2010-12-03 2011-07-20 北京工业大学 Frequency-converting speed-regulating fast online detecting device for specific oxygen uptake rate
CN102156432A (en) * 2011-02-22 2011-08-17 上海市城市建设设计研究院 Method for controlling aeration in biochemical reaction tank in real time
CN104787872A (en) * 2015-04-29 2015-07-22 梁锐振 Aeration rate control method and system

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