A BOD online monitoring system capable of intermittent or continuous sampling

Abstract

The present invention discloses a BOD online monitoring system capable of intermittent or continuous sampling, belonging to the technical field of environmental monitoring, and comprising an intermittent sampling module, a signal acquisition module, and a master control module. The intermittent sampling module is used to deliver a water sample to be tested to the signal acquisition module, the signal acquisition module is used to obtain a signal online in real time, and the signal acquisition and transmission module is used to acquire and transmit the signal to the master control module for calculating and displaying the BOD value, and controlling the operation of the entire system. The BOD online monitoring system with intermittent automatic sampling of the present invention can automatically deliver the water sample signal to be tested to the signal acquisition module in real time, adopt the microbial electrode method to perform BOD detection of the water sample to be tested, and can quickly determine the water sample of BOD through the master control module, and place all the control modules in a closed constant temperature environment, so the sample detection time is short, and the detection result is accurate and applicable to the BOD detection of surface water, groundwater, drinking water, pharmaceutical wastewater and some industrial wastewater. At the same time, intermittent or continuous sampling is satisfied.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental detection, and specifically discloses a BOD online monitoring system capable of intermittent and continuous sampling. Background Art

[0002] The detection of biochemical oxygen demand (hereinafter referred to as BOD) is an important indicator in environmental water quality monitoring. The traditional detection method mainly uses the 5-day cultivation method, which has a low success rate, a long time, and the data has a lag. It can only obtain BOD data 5 days ago, and it cannot be monitored 24 hours a day, which brings many inconveniences to environmental testing. The majority of environmental testing personnel urgently need a method of rapid measurement and 24-hour real-time monitoring to improve efficiency and reduce labor intensity. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a BOD online monitoring system capable of intermittent or continuous sampling in view of the deficiencies in the prior art, which not only greatly improves the detection accuracy, but also shortens the detection time of a single sample to about 8 minutes, and can achieve 24h real-time monitoring.

[0004] In order to solve the above technical problems, the present invention provides a BOD online monitoring system capable of intermittent or continuous sampling, comprising a constant temperature box, and an intermittent or continuous sampling module integrated with the constant temperature box, which is placed in the constant temperature box and is used to feed a water sample to be tested at a constant temperature and constant flow into the detection module;

[0005] The detection module is placed in the constant temperature box, and the signal output end of the detection module is connected to the signal input end of the signal acquisition and transmission module to obtain the detection signal in real time online;

[0006] The signal acquisition and transmission module is placed in the constant temperature box, and the signal output end of the signal acquisition and transmission module is connected to the master control module for collecting and transmitting the detection signal;

[0007] The master control module is placed outside the thermostat and includes a host computer, which is used to calculate the BOD value based on the received detection signal and control the operation of the entire system.

[0008] Specifically, the intermittent and continuous sampling module includes a water inlet pipe, a heater and a water outlet pipe. The heater and the water outlet pipe are placed in a constant temperature box. One end of the water inlet pipe is inserted into the water source to be tested, and the other end is connected to the water inlet of the heater. One end of the water outlet pipe is connected to the water outlet of the heater, and the other end is connected to the detection module. The water outlet pipe is provided with a water outlet temperature controller and a water outlet flow pump.

[0009] Specifically, the detection module includes a sample pool and a BOD sensor, the water outlet pipe is inserted into the bottom of the sample pool, and the BOD sensor is placed in the water sample to be tested in the sample pool.

[0010] Preferably, the BOD sensor has a built-in microbial membrane and adopts a microbial electrode method for detection.

[0011] Preferably, the sample pool is also connected to the overflow tank through an overflow pipe.

[0012] Preferably, the water inlet pipe is also provided with a water inlet delivery pump and a water inlet temperature detector.

[0013] Preferably, the outlet water temperature controller has a built-in PID controller, and the signal output end of the PID controller is electrically connected to the heater control end.

[0014] Preferably, the control ends of the outlet water temperature control controller and the outlet water flow pump are both connected to the master control template signal.

[0015] The BOD online monitoring system capable of intermittent and continuous sampling of the present invention has a sampling module, a detection module, a signal acquisition and transmission module and a master control module which are integrated with a constant temperature box. The constant temperature and constant current sampling module and the detection module are placed inside the constant temperature box, the signal acquisition and transmission module is placed on the back of the constant temperature box, the host computer of the master control module is placed on the front of the constant temperature box, the signal output end of the detection module is connected to the signal input end of the signal acquisition and transmission module, and the signal output end of the signal acquisition and transmission module is connected to the host computer; the signal acquisition and transmission module includes a circuit board, which is used to collect the detection signal of the BOD sensor and transmit it to the host computer and convey the operation instructions of the host computer.

[0016] The BOD sensor has a built-in microbial membrane and uses the microbial electrode method for detection. The microbial membrane is placed close to the oxygen permeable membrane surface of the galvanic dissolved oxygen electrode to form a microbial electrode. The flow detection method is adopted. Since the output signal value of the dissolved oxygen electrode is inversely proportional to the dissolved oxygen content, when the liquid without any organic matter flows through the sample pool, the assimilation of microorganisms is very small, so the dissolved oxygen flowing through the microbial membrane is almost not reduced. When the dissolved oxygen containing organic matter passes through the sample pool, the assimilation of microorganisms becomes abnormally active, consuming more dissolved oxygen, thus resulting in a decrease in the amount of dissolved oxygen flowing through the microbial membrane. This change in dissolved oxygen content directly causes the output of the dissolved oxygen electrode to change inversely, which proves that the output signal change value is inversely proportional to the content of organic matter in the sample, and the BOD value is calculated accordingly.

[0017] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0018] The BOD online monitoring system capable of intermittent and continuous sampling of the present invention can automatically and real-time deliver the water sample to be tested to the detection module by utilizing the sampling module, and adopts the microbial electrode method to perform BOD detection on the water sample to be tested. The detection result is accurate and reliable, and the BOD value of the water sample can be quickly determined. The system is easy to operate and accurate in measurement. The detection time of a single sample is only about 8 minutes. The system is widely applicable to the detection of BOD in surface water, groundwater, drinking water, wastewater from the pharmaceutical industry, and industrial wastewater that does not contain any obvious toxic effects on microorganisms.

[0019] All control modules are placed in a closed constant temperature environment, so the sample detection time is short, the detection results are accurate and reliable, and it is widely used in BOD detection of surface water, groundwater, drinking water, pharmaceutical wastewater and some industrial wastewater. The intermittent sampling BOD online monitoring system of the present invention can be used for intermittent sampling and continuous sampling. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the overall block diagram of the BOD online monitoring system capable of intermittent or continuous sampling of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the BOD online monitoring system capable of intermittent and continuous sampling of the present invention.

[0022] Legend:

[0023] 10-constant temperature box; 20-sampling module; 21-water inlet pipe; 22-water inlet delivery pump; 23-water inlet temperature detector; 24-heater; 25-water outlet pipe; 26-water outlet temperature controller; 27-water outlet flow pump; 30-detection module; 31-sample pool; 32-BOD sensor; 33-fixed box; 40-signal acquisition and transmission module; 50-master control module; 61-overflow pipe; 62-overflow pool. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0025] This embodiment provides a BOD online monitoring system capable of intermittent or continuous sampling. Figure 1 and Figure 2 As shown, it includes a thermostat 10 and the thermostat 10 integrated with the thermostat 10:

[0026] The sampling module 20 is placed in the thermostat 10 and is used to feed the water sample to be tested with constant temperature and constant flow into the detection module 20. The sampling module 20 includes an inlet pipe 21, a heater 24 and an outlet pipe 25. The heater 24 and the outlet pipe 25 are both placed in the thermostat 10. One end of the inlet pipe 21 is inserted into the water source to be tested, and the other end is connected to the water inlet of the heater 24. The inlet pipe 21 is provided with an inlet pump 22 and an inlet temperature detector 23, which are used to transport the water sample to be heated to the heater 24. One end of the outlet pipe 25 is connected to the water outlet of the heater 24, and the other end is connected to the detection module 30. The outlet pipe 25 is provided with an outlet temperature controller 26 and an outlet flow pump 27. The outlet temperature controller 26 has a built-in PI D controller, the signal output end of the PID controller is electrically connected to the control end of the heater 24. When the water temperature detected by the outlet water temperature control controller 26 is lower than the set value, the PID controller controls the heater 24 to work and heat the water temperature to the set value. Moreover, since the outlet water pipe 25 is located in the incubator 10, the heat loss is small. Even if there are some slight fluctuations in the temperature of the water sample to be tested, they are all controlled within a reasonable range and will not affect the test results. The outlet water flow pump 27 is used to transport the water sample to be tested and adjust the sampling flow rate of the water sample to be tested according to the set value. The control ends of the outlet water temperature controller 26 and the outlet water flow pump 27 are both connected to the master control template 50 by signal, and are used to control the water temperature and flow rate of the water sample to be tested according to the instructions.

[0027] The detection module 30 is placed in the constant temperature box 10. The signal output end of the detection module 30 is connected to the signal input end of the signal acquisition and transmission module 40 for real-time online acquisition of the detection signal. The detection module 30 includes a sample pool 31 and a BOD sensor 32. The outlet pipe 25 is inserted into the bottom of the sample pool 31 for introducing a constant temperature and constant flow water sample to be tested into the sample pool 31. The BOD sensor 32 is placed in a fixed box 33, which is fixed in the sample pool 31. The water sample to be tested in the sample pool 31 can flow into the fixed box 33. The BOD sensor 32 has a built-in microbial membrane and adopts the microbial electrode method for detection. The microbial membrane is closely attached to the oxygen permeable membrane surface of the galvanic cell type dissolved oxygen electrode to form a microbial electrode. The flow detection method is adopted. Since the output signal value of the dissolved oxygen electrode is inversely proportional to the dissolved oxygen content, when a liquid not containing any organic matter flows through the sample pool 31, the assimilation effect of the microorganisms is very small, so the dissolved oxygen flowing through the microbial membrane is almost not reduced. When dissolved oxygen containing organic matter passes through the sample pool 31, the assimilation of microorganisms becomes abnormally active, consuming more dissolved oxygen, thus causing the amount of dissolved oxygen flowing through the microbial membrane to decrease. This change in dissolved oxygen content directly causes the output of the dissolved oxygen electrode to change inversely, proving that the output signal change value is inversely proportional to the content of organic matter in the sample, and the BOD value is calculated accordingly.

[0028] The signal acquisition and transmission module 40 is placed on the back of the thermostat 10. The signal output end of the signal acquisition and transmission module 40 is connected to the master control module 50 for collecting and transmitting the detection signal.

[0029] The master control module 50 is placed outside the thermostat 10 and includes a host computer for calculating the BOD value based on the received detection signal. The master control module 50 is also connected to the control end signals of the outlet water temperature controller 26 and the outlet water flow pump 27 to control the temperature and flow of the water sample to be tested according to instructions.

[0030] As a preferred embodiment of the present invention, the sample pool 31 is also connected to the overflow pool 62 through the overflow pipe 61.

[0031] During the detection, turn on the host computer, take the BOD sensor 32 out of the fixed box 33, lay the BOD sensor 32 flat, wipe the water stains on the surface of the BOD sensor 32 and put it back into the fixed box 33 to eliminate the influence of the water stains on the surface of the BOD sensor 32; then, add the calibration water sample with set temperature and set flow rate into the sample pool 31, obtain the detection signal of the calibration water sample, repeat the operation twice to achieve the purpose of calibration stability; then add the water sample to be tested with constant temperature and constant flow into the sample pool 31, and obtain the detection signal of the water sample to be tested after the temperature and flow rate of the sample pool 31 are stable, and calculate the BOD value of the water sample to be tested according to the detection signal of the calibration water sample, and the host computer automatically records the detection time and the BOD value of the test water sample, and saves it as needed. For the detection of the same water source, only one calibration is required, and the detection can be carried out continuously, and the detection results are saved every few minutes to achieve the purpose of real-time online monitoring.

[0032] The BOD online monitoring system capable of intermittent and continuous sampling of the present invention can automatically and in real time deliver a constant-temperature water sample to be tested to a detection module by utilizing a sampling module, and adopts a microbial electrode method to perform BOD detection on the water sample to be tested. The detection result is accurate and reliable, and the BOD value of the water sample can be quickly determined. The system is also simple to operate, accurate in measurement, and short in single sample detection time. The system is widely applicable to the detection of BOD of surface water, groundwater, domestic drinking water, pharmaceutical industry wastewater, and industrial wastewater that does not contain wastewater that has obvious toxic effects on microorganisms.

[0033] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. A person skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the present invention.

Claims

1. A BOD online monitoring system capable of intermittent or continuous sampling, characterized in that: It comprises a thermostat (10) and the following integrated with the thermostat (10): A constant temperature and constant flow sample introduction module (20), placed in the constant temperature box (10), is used to introduce a water sample to be tested at a constant temperature and constant flow into the detection module (30); The detection module (30) is placed in the constant temperature box (20), and the signal output end of the detection module (30) is connected to the signal input end of the signal acquisition and transmission module (40) for obtaining the detection signal online in real time; A signal acquisition and transmission module (40) is placed in the constant temperature box (20), and a signal output end of the signal acquisition and transmission module (40) is connected to the main control module (50) for acquiring and transmitting detection signals; The master control module (50) is placed outside the thermostatic box (20) and includes a host computer, which is used to calculate the BOD value according to the received detection signal and control the operation of the entire system.

2. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 1, characterized in that: The constant temperature and constant flow injection module (20) comprises a heater (24) and a water outlet pipe (25), the water inlet of the heater (24) is connected to the water inlet pipe (21), the water inlet pipe (21) is connected to a water source to be tested, the water outlet of the heater (24) is connected to the water outlet pipe (25), the water outlet pipe (25) is connected to the detection module (30), and the water outlet pipe (25) is provided with a water outlet temperature controller (26) and a water outlet flow pump (27).

3. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 2, characterized in that: The detection module (30) comprises a sample pool (31) and a BOD sensor (32), the water outlet pipe (25) is inserted into the bottom of the sample pool (31), and the BOD sensor (32) is placed in the water sample to be tested in the sample pool (31).

4. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 3, characterized in that: The BOD sensor (32) has a built-in microbial membrane.

5. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 3, characterized in that: The sample pool (31) is also connected to the overflow pool (62) through an overflow pipe (61).

6. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 2, characterized in that: The water inlet pipe (21) is also provided with a water inlet delivery pump (22) and a water inlet temperature detector (23).

7. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 2, characterized in that: The outlet water temperature controller (26) has a built-in PID controller, and the signal output end of the PID controller is connected to the control end of the heater (24).

8. The BOD online monitoring system capable of intermittent and continuous sampling as claimed in claim 7, characterized in that: The control ends of the outlet water temperature controller (26) and the outlet water flow pump (27) are both connected to the master control template (50) by signal.

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