CN202693518U - Dissolved oxygen monitoring system based on polarographic electrode - Google Patents
Dissolved oxygen monitoring system based on polarographic electrode Download PDFInfo
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- CN202693518U CN202693518U CN 201220159579 CN201220159579U CN202693518U CN 202693518 U CN202693518 U CN 202693518U CN 201220159579 CN201220159579 CN 201220159579 CN 201220159579 U CN201220159579 U CN 201220159579U CN 202693518 U CN202693518 U CN 202693518U
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Abstract
The utility model discloses a dissolved oxygen monitoring system based on a polarographic electrode and relates to the technical field of water quality monitoring. The system comprises a polarographic electrode, a temperature sensor, a transmitter, an acquisition element and a control element, wherein the polarographic electrode, the transmitter, the acquisition element and the control element are connected in sequence; and the temperature sensor is connected with the control element. According to the utility model, through the adoption of the temperature sensor, when the concentration of dissolved oxygen is measured, effect of temperature on the concentration of the dissolved oxygen is considered, thereby improving the measuring accuracy of the concentration of the dissolved oxygen.
Description
Technical field
The utility model relates to the water quality inspection technique field, particularly a kind of dissolved oxygen DO monitoring system based on the polarogram electrode.
Background technology
Dissolved oxygen concentration is one of important indicator of water quality.The monitoring of dissolved oxygen concentration not only can effectively prevent and treat water pollution, and can provide decision support for culture fishery, be conducive to improve aquaculture production power, also be the very important technical indicator of biofermentation industrial circle simultaneously, the dissolved oxygen concentration in the quantitative measurment water body is significant.
At present the pick-up unit of dissolved oxygen concentration has been done large quantity research, has mainly concentrated on the development to sensor probe, but because and reckon without temperature to the impact of measured value, cause the measuring accuracy of dissolved oxygen concentration lower.
The utility model content
The technical matters that (one) will solve
The technical problems to be solved in the utility model is: the measuring accuracy that how to improve dissolved oxygen concentration.
(2) technical scheme
For solving the problems of the technologies described above, the utility model provides a kind of dissolved oxygen DO monitoring system based on the polarogram electrode, described system comprises: polarogram electrode, temperature sensor, transmitter, collecting unit and control module, described polarogram electrode, transmitter, collecting unit and control module connect successively, and described temperature sensor is connected with described control module;
Described control module is powered to described polarogram electrode by described transmitter, described polarogram electrode obtains the response current of electrolytic solution in the described polarogram electrode, and described response current is sent to described transmitter, described transmitter carries out current/voltage-converted to described response current, to obtain response voltage, described collecting unit gathers described response voltage, and described response voltage is sent to described control module, the temperature of electrolytic solution in the described polarogram electrode of described temperature sensor measurement, and described temperature is sent to described control module, described control module utilizes the corresponding relation between response current and the response voltage, and response current, corresponding relation between temperature and the dissolved oxygen concentration calculates the dissolved oxygen concentration that obtains described electrolytic solution.
Preferably, described polarogram electrode comprises: shell, negative electrode, positive electrode and oxygen flow film, be provided with electrolytic solution in the described shell, described negative electrode and positive electrode all are located in the described shell, described negative electrode is connected an end and is all stretched in the described electrolytic solution and the other end all is connected with described transmitter with positive electrode, described oxygen flow film is located on the described shell.
Preferably, described temperature sensor is digital temperature sensor.
Preferably, described transmitter comprises current/voltage-converted circuit, second-order low-pass filter circuit and the amplifying circuit that connects successively, described current/voltage-converted circuit carries out current/voltage-converted to described response current, to obtain response voltage, described second-order low-pass filter circuit carries out filtering to described response voltage, and described amplifying circuit amplifies described response voltage.
Preferably, described system also comprises: with the display that described control module is connected, described display is used for showing the dissolved oxygen concentration of described current electrolytic solution.
Preferably, described display is provided with the touch-screen that is connected with described control module, and described touch-screen is used for receiving user's operational order.
Preferably, described system also comprises: with the storage unit that described control module is connected, described storage unit is used for storing the dissolved oxygen concentration of described current electrolytic solution.
Preferably, described system also comprises: with the communication unit that described control module is connected, described communication unit is used for the communication between realization native system and other equipment.
Preferably, described system also comprises: with the Power Management Unit that described control module is connected, described Power Management Unit is used under the control of described control module, realizes the active device in the described system is powered.
Preferably, described system also comprises: with the device control cell that described control module is connected, described device control cell is used for the control oxygen increasing equipment.
(3) beneficial effect
The utility model when measuring dissolved oxygen concentration, considers that temperature on the impact of described dissolved oxygen concentration, has improved the measuring accuracy of dissolved oxygen concentration by the set temperature sensor.
Description of drawings
Fig. 1 is the structured flowchart based on the dissolved oxygen DO monitoring system of polarogram electrode according to a kind of embodiment of the utility model;
Fig. 2 is the structural representation of system shown in Figure 1;
Fig. 3 is the control flow chart of system shown in Figure 1.
Wherein, 1: shell; 2: the oxygen flow film; 3: negative electrode; 4: positive electrode; 5: electrolytic solution; 6: temperature sensor; 7: transmitter; 8: water joint; 9: main frame; 10: display; 11: wire; 12: connection.
Embodiment
Below in conjunction with drawings and Examples, embodiment of the present utility model is described in further detail.Following examples are used for explanation the utility model, but are not used for limiting scope of the present utility model.
Fig. 1 is the structured flowchart based on the dissolved oxygen DO monitoring system of polarogram electrode according to a kind of embodiment of the utility model; With reference to Fig. 1, the system of described embodiment comprises: polarogram electrode, temperature sensor, transmitter, collecting unit and control module, described polarogram electrode, transmitter, collecting unit and control module connect successively, and described temperature sensor is connected with described control module;
Described control module is powered to described polarogram electrode by described transmitter, described polarogram electrode obtains the response current of electrolytic solution in the described polarogram electrode, and described response current is sent to described transmitter, described transmitter carries out current/voltage-converted to described response current, to obtain response voltage, described collecting unit gathers described response voltage, and described response voltage is sent to described control module, the temperature of electrolytic solution in the described polarogram electrode of described temperature sensor measurement, and described temperature is sent to described control module, described control module utilizes the corresponding relation between response current and the response voltage, and response current, corresponding relation between temperature and the dissolved oxygen concentration calculates the dissolved oxygen concentration that obtains described electrolytic solution.
In the present embodiment, described control module is the C8051F020 single-chip microcomputer; Described signal gathering unit realizes the conversion of response voltage from the simulating signal to the digital signal to transmitter output, the analog/digital converter of described collecting unit (ADC) uses the built-in ADC of C8051F020 single-chip microcomputer, and conversion reference voltage is used inner 2.4V voltage reference.
With reference to Fig. 2, preferably, described polarogram electrode comprises: shell 1, negative electrode 3, positive electrode 4 and oxygen flow film 2, be provided with electrolytic solution 5 in the described shell 1, described negative electrode 3 and positive electrode 4 all are located in the described shell 1, the end that described negative electrode 3 is connected with positive electrode all stretches in the described electrolytic solution 5 and the other end all is connected with described transmitter 7, described oxygen flow film 2 is located on the described shell 1, in the present embodiment, wherein negative electrode 3 is the platinum wire of 0.3mm for diameter, and positive electrode 4 is the filamentary silver of 0.3mm for diameter; Described polarogram electrode needs polarizing voltage 0.425V, about 60s of its response time.
In the present embodiment, described shell 1 is stainless steel casing, described stainless steel casing diameter 18mm, the material of oxygen flow film 2 is fluoroplastic/silicon rubber/stainless steel cloth composite membrane, negative electrode 3 is the platinum wire of 0.3mm for diameter, positive electrode 4 is the filamentary silver of 0.3mm for diameter, and electrolytic solution 5 is Klorvess Liquid.During measurement, be dissolved in oxygen in the solution to be measured by described oxygen flow film diffusion to the inside of described polarogram electrode, the electrolytic solution 5 in described polarogram electrode arrives negative electrode 3 surfaces, under suitable polarizing voltage electrochemical reaction occuring, and produces response current.
The filamentary silver of the platinum wire of negative electrode 3 and positive electrode 4 consists of measuring circuit by electrolytic solution 5 under the effect of polarizing voltage, the reaction that negative and positive two electrodes occur in this process is as follows:
Negative electrode: O
2+ 2H
2O+4e
-→ 4OH
-
Positive electrode: 4Ag+4Cl
-→ 4AgCl+4e
-
According to Faraday's law: the electric current and the partial pressure of oxygen that flow through electrode are directly proportional, thus electrode at a certain temperature output current and oxygen concentration between linear.So just can calculate according to the size of electrode output current the size of oxygen concentration in the solution.
The response formula of electrode is:
In the formula, I is response current;
Be the partial pressure of oxygen in the electrolytic solution (described partial pressure of oxygen is one of form of expression of dissolved oxygen concentration); T is the oxygen permeation membrane working temperature; A is two constants relevant with electrode material and structure with A.
Preferably, in the present embodiment, described temperature sensor 6 is digital temperature sensor DS18B20, be used for realization to the conversion of temperature from the physical quantity to the electrical quantities of electrolytic solution, described digital temperature sensor DS18B20 is sealed in the stainless-steel tube that diameter is 8mm, this temperature sensor is fixed on the stainless steel low side, be close to stainless steel inside pipe wall, environment has good heat sensitivity to external world, DS18B20 adopts the 3.3V Power supply, unibus communication, temperature-measuring range are-55 ℃～+ 125 ℃, and accuracy of detection is ± 0.5 ℃.When systematic survey, temperature sensor and polarogram electrode are placed in the solution to be measured (temperature that is used for electrolytic solution is identical with solution temperature to be measured, therefore when being placed on temperature sensor and polarogram electrode in the solution to be measured, can obtain the temperature of electrolytic solution in the polarogram electrode), can guarantee the accurately temperature of electrolytic solution 5 in the polarogram electrode of system acquisition.
Preferably, described transmitter 7 comprises the current/voltage-converted circuit that connects successively, the second-order low-pass filter circuit, and amplifying circuit, described current/voltage-converted circuit carries out current/voltage-converted to described response current, to obtain response voltage, described second-order low-pass filter circuit carries out filtering to described response voltage, described amplifying circuit amplifies described response voltage, in the present embodiment, described current/voltage-converted circuit, the second-order low-pass filter circuit, and amplifying circuit all is sealed in high-strength polyvinyl chloride (Poly Vinyl Chloride, PVC) in the plastics, can enter fully in the water, described current/voltage-converted circuit realizes that with the 1M resistance that is connected across this amplifier reverse input end and output terminal electric current is to the conversion of voltage by high precision operating amplifier OPA277.Then the second-order low-pass filter that consists of by OP07, filter the HF noise signal in the circuit, the secondary amplifying circuit that again consists of through amplifier AD620, obtain the Voltage-output of 0～2.4V, the internal circuit of transmitter all passes through the sealant pouring and sealing water-proofing treatment, the output of transmitter 7 is connected with main frame 9 by wire 11, and wire 11 all passes through water joint 8 with connection 12 and is connected main frame 9, and described main frame 9 comprises control module.
Preferably, described system also comprises: the display 10 that is connected with described control module, described display 10 is used for showing the dissolved oxygen concentration of described current electrolytic solution, also can be used for realizing to temperature, and the demonstration of working state of system.
Preferably, described display 10 is provided with the touch-screen that is connected with described control module, described touch-screen is used for receiving user's operational order, with the interactive function of realization with the user, come system is carried out the operations such as menu setecting, system's setting and control model selection by screen operator, can realize that real time data demonstration, the inquiry of historical data, historical data curve display, transducer calibration, system time setting, the selection of equipment control mode, the setting of dissolved oxygen concentration bound, the setting of device start time, the timing controlled time interval are set etc.
The control flow of system as shown in Figure 3, during the user selection automatic control mode, need to set the automatically dissolved oxygen concentration bound of control, system judges at first whether collect dissolved oxygen concentration satisfies the bound that the user sets during work, if surpass the least concentration of dissolved oxygen concentration, system carries out dissolved oxygen concentration is regulated with regard to automatically opening oxygen increasing equipment, if surpass the maximum concentration limit, system just closes oxygen increasing equipment, is that dissolved oxygen concentration lowers.During the user selection timing controlled, can set a device start time, when system time is consistent with start-up time, will start oxygen increasing equipment, the user can also set three time periods, the time span of within each time period, setting three device starts and closing, system can set in strict accordance with the user, opens and closes automatically equipment according to the time span of setting within these three time periods.
From can finding out with above-mentioned control flow, the utility model can be widely used in aquaculture factory, biofermentation pond, sewage treatment plant, environmental administration to the monitoring field of dissolved oxygen concentration, has the advantage of convenient easy-to-use, complete function.
Preferably, described system also comprises: the storage unit that is connected with described control module, described storage unit is used for storing the dissolved oxygen concentration of described current electrolytic solution, but storage system job information also, in the present embodiment, the storage chip of described storage unit uses the mass storage AM29LV040B of 512K, 3.3V single power supply, 10 bytes of every record, storer divides 8 pages of storage spaces, altogether can store 49152 data.
Preferably, described system also comprises: the communication unit that is connected with described control module, described communication unit is used for the communication between realization native system and other equipment, in the present embodiment, the interface of described communication unit uses the RS-485 communication interface, Modbus communications protocol by standard adopts far-end measurement and control unit device (Remote Terminal Unit, RTU) mode transfer data.
Preferably, described system also comprises: the Power Management Unit that is connected with described control module, described Power Management Unit is used under the control of described control module, realization is powered to the active device in the described system, supply voltage than wide input range can be provided, for different active devices provide respectively+5V ,-5V and+voltage of 3.3V, satisfy different power supply requirements.
Preferably, described system also comprises: with the device control cell that described control module is connected, described device control cell is used for the oxygen increasing equipments such as control aerator, and the output of 8 railway digitals can be provided, and realizes automatically control or timing controlled according to the control law of system.
In the present embodiment, be connected by 0.5m left and right sides high-quality wire between described polarogram electrode and the transmitter, be connected by the 0.5m wire between transmitter and the collecting unit, digital temperature sensor directly is connected with control module by three-core conductor.
The principle of work of system of the present utility model is: described polarogram electrode is positioned in the solution to be measured, make the electrolytic solution in the described polarogram electrode consistent with the dissolved oxygen concentration of described solution to be measured, therefore only need calculate the dissolved oxygen concentration of the electrolytic solution in the described polarogram electrode, can know the dissolved oxygen concentration of described solution to be measured.
Described control module is powered to described polarogram electrode by described transmitter, described polarogram electrode obtains the response current of electrolytic solution in the described polarogram electrode, and described response current is sent to described transmitter, described transmitter carries out current/voltage-converted to described response current, to obtain response voltage, described collecting unit gathers described response voltage, and described response voltage is sent to described control module, the temperature of electrolytic solution in the described polarogram electrode of described temperature sensor measurement, and described temperature is sent to described control module, described control module utilizes the corresponding relation between response current and the response voltage, and response current, corresponding relation between temperature and the dissolved oxygen concentration calculates the dissolved oxygen concentration that obtains described electrolytic solution.
The system of present embodiment compared with prior art also has following advantage:
1, the utility model detects dissolved oxygen DO and has done systemic processing, integrated sensing, become send, gather, store, transmit, the several functions modules such as demonstration, control, powerful.
2, the utility model is with display module, and the dissolved oxygen concentration information and the temperature information that collect show that in real time the user does not need the data derivation directly just can be seen simple, intuitive.
3, the utility model employing touch-screen, display and operation can both be finished, and is elegant in appearance, only needs simply to press just energy complete operation in interface point, easy to use.
4, the utlity model has the control function, can realize the control to 8 pipeline equipments.
5, the utility model can allow the customization control mode, has two kinds of control models of automatic control and timing controlled to select.Automatically control is according to the dissolved oxygen concentration that gathers, and system oneself has judged whether to exceed the dissolved oxygen DO bound that the user sets, if transfinite, automatically conditioning equipment start and stop realize the control to dissolved oxygen concentration.Timing controlled can start or arrestment according to user's setting-up time, realizes the adjusting to dissolved oxygen concentration.
6, the utility model control parametric user can customize, and arranges flexibly, and the bound that dissolved oxygen concentration can be set is used for automatic control mode, and the equipment start-stop timing can be set, and can the setting-up time section realize the automatic training in rotation control of equipment simultaneously.
Above embodiment only is used for explanation the utility model; and be not limitation of the utility model; the those of ordinary skill in relevant technologies field; in the situation that does not break away from spirit and scope of the present utility model; can also make a variety of changes and modification; therefore all technical schemes that are equal to also belong to category of the present utility model, and scope of patent protection of the present utility model should be defined by the claims.
Claims (10)
1. dissolved oxygen DO monitoring system based on the polarogram electrode, it is characterized in that, described system comprises: polarogram electrode, temperature sensor, transmitter, collecting unit and control module, described polarogram electrode, transmitter, collecting unit and control module connect successively, and described temperature sensor is connected with described control module;
Described control module is powered to described polarogram electrode by described transmitter, described polarogram electrode obtains the response current of electrolytic solution in the described polarogram electrode, and described response current is sent to described transmitter, described transmitter carries out current/voltage-converted to described response current, to obtain response voltage, described collecting unit gathers described response voltage, and described response voltage is sent to described control module, the temperature of electrolytic solution in the described polarogram electrode of described temperature sensor measurement, and described temperature is sent to described control module, described control module utilizes the corresponding relation between response current and the response voltage, and response current, corresponding relation between temperature and the dissolved oxygen concentration calculates the dissolved oxygen concentration that obtains described electrolytic solution.
2. the system as claimed in claim 1, it is characterized in that, described polarogram electrode comprises: shell, negative electrode, positive electrode and oxygen flow film, be provided with electrolytic solution in the described shell, described negative electrode and positive electrode all are located in the described shell, described negative electrode is connected an end and is all stretched in the described electrolytic solution and the other end all is connected with described transmitter with positive electrode, described oxygen flow film is located on the described shell.
3. the system as claimed in claim 1 is characterized in that, described temperature sensor is digital temperature sensor.
4. the system as claimed in claim 1, it is characterized in that, described transmitter comprises current/voltage-converted circuit, second-order low-pass filter circuit and the amplifying circuit that connects successively, described current/voltage-converted circuit carries out current/voltage-converted to described response current, to obtain response voltage, described second-order low-pass filter circuit carries out filtering to described response voltage, and described amplifying circuit amplifies described response voltage.
5. such as each described system in the claim 1～4, it is characterized in that described system also comprises: with the display that described control module is connected, described display is used for showing the dissolved oxygen concentration of described current electrolytic solution.
6. system as claimed in claim 5 is characterized in that, described display is provided with the touch-screen that is connected with described control module, and described touch-screen is used for receiving user's operational order.
7. such as each described system in the claim 1～4, it is characterized in that described system also comprises: with the storage unit that described control module is connected, described storage unit is used for storing the dissolved oxygen concentration of described current electrolytic solution.
8. such as each described system in the claim 1～4, it is characterized in that described system also comprises: with the communication unit that described control module is connected, described communication unit is used for the communication between realization native system and other equipment.
9. such as each described system in the claim 1～4, it is characterized in that, described system also comprises: with the Power Management Unit that described control module is connected, described Power Management Unit is used under the control of described control module, realizes the active device in the described system is powered.
10. such as each described system in the claim 1～4, it is characterized in that described system also comprises: with the device control cell that described control module is connected, described device control cell is used for the control oxygen increasing equipment.
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| CN 201220159579 CN202693518U (en) | 2012-04-13 | 2012-04-13 | Dissolved oxygen monitoring system based on polarographic electrode |
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| CN 201220159579 CN202693518U (en) | 2012-04-13 | 2012-04-13 | Dissolved oxygen monitoring system based on polarographic electrode |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104807862A (en) * | 2015-04-20 | 2015-07-29 | 中国农业大学 | Method and device for detecting dissolved oxygen in water |
| CN106442677A (en) * | 2016-11-28 | 2017-02-22 | 福州微启迪物联科技有限公司 | Intelligent dissolved oxygen electrode without production calibration |
| CN106546647A (en) * | 2016-11-25 | 2017-03-29 | 福州微启迪物联科技有限公司 | A kind of intelligent telemetering dissolved oxygen meter and its implementation based on NB IoT |
| CN114983401A (en) * | 2022-04-20 | 2022-09-02 | 北京秋满实医疗科技有限公司 | Sensor for measuring the transcutaneous partial pressure of oxygen at a body part of a patient |
-
2012
- 2012-04-13 CN CN 201220159579 patent/CN202693518U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104807862A (en) * | 2015-04-20 | 2015-07-29 | 中国农业大学 | Method and device for detecting dissolved oxygen in water |
| CN106546647A (en) * | 2016-11-25 | 2017-03-29 | 福州微启迪物联科技有限公司 | A kind of intelligent telemetering dissolved oxygen meter and its implementation based on NB IoT |
| CN106442677A (en) * | 2016-11-28 | 2017-02-22 | 福州微启迪物联科技有限公司 | Intelligent dissolved oxygen electrode without production calibration |
| CN106442677B (en) * | 2016-11-28 | 2019-04-30 | 福州微启迪物联科技有限公司 | A kind of intelligent dissolved oxygen electrode without production calibration |
| CN114983401A (en) * | 2022-04-20 | 2022-09-02 | 北京秋满实医疗科技有限公司 | Sensor for measuring the transcutaneous partial pressure of oxygen at a body part of a patient |
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Granted publication date: 20130123 Termination date: 20130413 |