CN115165994A - Device and method for measuring nitrous oxide emission of sewage treatment plant - Google Patents
Device and method for measuring nitrous oxide emission of sewage treatment plant Download PDFInfo
- Publication number
- CN115165994A CN115165994A CN202210917287.9A CN202210917287A CN115165994A CN 115165994 A CN115165994 A CN 115165994A CN 202210917287 A CN202210917287 A CN 202210917287A CN 115165994 A CN115165994 A CN 115165994A
- Authority
- CN
- China
- Prior art keywords
- gas
- nitrous oxide
- chamber
- dehumidification
- measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical compound [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 title claims abstract description 296
- 239000001272 nitrous oxide Substances 0.000 title claims abstract description 148
- 239000010865 sewage Substances 0.000 title claims abstract description 42
- 238000000034 method Methods 0.000 title claims description 20
- 238000007791 dehumidification Methods 0.000 claims abstract description 59
- 239000007791 liquid phase Substances 0.000 claims abstract description 32
- 238000006243 chemical reaction Methods 0.000 claims abstract description 31
- 239000012071 phase Substances 0.000 claims abstract description 24
- 239000007788 liquid Substances 0.000 claims abstract description 19
- 238000005259 measurement Methods 0.000 claims abstract description 18
- 239000007789 gas Substances 0.000 claims description 167
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 18
- 238000005485 electric heating Methods 0.000 claims description 14
- 239000000741 silica gel Substances 0.000 claims description 12
- 229910002027 silica gel Inorganic materials 0.000 claims description 12
- 239000007792 gaseous phase Substances 0.000 claims description 10
- 238000004458 analytical method Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 238000009423 ventilation Methods 0.000 claims description 2
- 239000012295 chemical reaction liquid Substances 0.000 claims 1
- 238000012544 monitoring process Methods 0.000 abstract description 11
- 229910052799 carbon Inorganic materials 0.000 abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 5
- 230000007774 longterm Effects 0.000 abstract description 4
- 229960001866 silicon dioxide Drugs 0.000 description 9
- 238000005273 aeration Methods 0.000 description 5
- 238000001514 detection method Methods 0.000 description 5
- 238000012545 processing Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 239000002274 desiccant Substances 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005264 electron capture Effects 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/26—Drying gases or vapours
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/26—Drying gases or vapours
- B01D53/261—Drying gases or vapours by adsorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/26—Drying gases or vapours
- B01D53/28—Selection of materials for use as drying agents
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N1/24—Suction devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2253/00—Adsorbents used in seperation treatment of gases and vapours
- B01D2253/10—Inorganic adsorbents
- B01D2253/106—Silica or silicates
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- General Chemical & Material Sciences (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Biomedical Technology (AREA)
- Electrochemistry (AREA)
- Sampling And Sample Adjustment (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a device for measuring nitrous oxide emission of a sewage treatment plant, belonging to the technical field of biological sewage treatment technology and carbon emission monitoring, and comprising a reaction tank, a gas collecting chamber, a gas pump, a gas flowmeter, a dehumidification chamber, a PLC (programmable logic controller), a gas-phase nitrous oxide analyzer, a nitrous oxide microelectrode, a liquid-phase nitrous oxide measuring host and a computer; the gas collecting chamber is fixed above the liquid level of the reaction tank, the gas collecting chamber is connected with a gas pump, the gas pump is connected with a gas flowmeter, the gas flowmeter is connected with a dehumidifying chamber, the dehumidifying chamber is connected with a gaseous nitrous oxide analyzer, and the dehumidifying chamber is also electrically connected with a PLC (programmable logic controller); the nitrous oxide microelectrode is connected with the liquid phase nitrous oxide measurement host, and the nitrous oxide microelectrode is arranged below the liquid surface of the reaction tank; the invention realizes high automation by utilizing the PLC, and can realize the long-term continuous online monitoring of liquid phase and gas phase nitrous oxide in the reaction tank of the sewage treatment plant.
Description
Technical Field
The invention belongs to the technical field of biological sewage treatment and carbon emission monitoring, and particularly relates to a device and a method for measuring nitrous oxide emission of a sewage treatment plant.
Background
Nitrous oxide is a strong greenhouse gas, has a long retention time in the atmosphere of 116 years, shows a strong greenhouse effect (265 times that of carbon dioxide), and consumes stratospheric ozone. Under the current 'double-carbon policy', the monitoring of nitrous oxide emission and the formulation of related emission reduction policies have important practical significance. The sewage treatment plant is a typical artificial emission source of nitrous oxide and accounts for 3.7 percent of the total annual emission amount of nitrous oxide in the world. Nitrous oxide emissions are also an important component of the carbon footprint of sewage treatment plants (up to 83% occupancy). For monitoring nitrous oxide emission of a sewage treatment plant, sampling off-line analysis is generally adopted at present, firstly, sampling is carried out at a fixed point in a reaction tank, then a gas chromatograph equipped with an Electron Capture Detector (ECD) is used for detecting the concentration of nitrous oxide of a sample, and a liquid sample needs to be subjected to complex pretreatment to obtain dissolved nitrous oxide gas so as to carry out concentration determination. Sampling off-line analysis needs higher sampling cost, the detection process is more complex and is only suitable for short-term monitoring, and because the nitrous oxide yield difference of sewage treatment plants in different operation time periods is obvious, the existing determination method cannot carry out continuous monitoring, so that the estimated total amount often has larger errors, and the data reliability is low. Therefore, the device and the method for measuring the nitrous oxide emission of the sewage treatment plant on line for a long time are very important to explore, and have higher practical significance for quantifying and evaluating the carbon emission of the sewage treatment plant, and the device and the method are reliable and labor-saving. Therefore, how to provide a device and a method for measuring nitrous oxide emission in a sewage treatment plant is an urgent problem to be solved by those skilled in the art.
Disclosure of Invention
The invention mainly aims to provide a device and a method for measuring nitrous oxide emission of a sewage treatment plant, so as to solve the technical problems. The device and the method can be used for simultaneously carrying out long-term continuous online monitoring on the liquid phase nitrous oxide and the gas phase nitrous oxide in the reaction tank, the device is simple in structure, labor cost is saved, the measurement result is accurate and reliable, a data base is provided for calculating the nitrous oxide emission amount and the output of a sewage treatment plant, and the device and the method have good application prospects.
In order to achieve the purpose, the invention adopts the following technical scheme:
a device for measuring nitrous oxide emission of a sewage treatment plant comprises a reaction tank, a gas collecting chamber, a gas pump, a gas flowmeter, a dehumidification chamber, a PLC (programmable logic controller), a gas-phase nitrous oxide analyzer, a nitrous oxide microelectrode, a liquid-phase nitrous oxide measuring host and a computer; the gas collection chamber is arranged above the liquid level of the reaction tank, the gas collection chamber is connected with a gas pump, the gas pump is connected with a gas flowmeter, the gas flowmeter is connected with a gas inlet of the dehumidification chamber, a gas outlet of the dehumidification chamber is connected with a gas phase nitrous oxide analyzer, the dehumidification chamber is also electrically connected with a PLC (programmable logic controller), and the gas phase nitrous oxide analyzer is connected with a gas outlet; the nitrous oxide microelectrode is connected with a liquid phase nitrous oxide measurement host, the liquid phase nitrous oxide measurement host is electrically connected with a computer, and the nitrous oxide microelectrode is arranged below the liquid level of the reaction tank.
Further, the dehumidification chamber includes vent, air discharge fan, thermometer, allochroic silica gel drier, observation window, porous tray, electric heating wire and humidity transducer, the air discharge fan is installed to the vent bottom, the air discharge fan below is provided with the allochroic silica gel drier, porous tray is installed to the bottom of allochroic silica gel drier, electric heating wire is installed to the bottom of porous tray, humidity transducer is installed to the gas outlet department of dehumidification chamber, observation window is installed to the dehumidification chamber, dehumidification chamber internally mounted has the thermometer.
Further, the gas collecting chamber comprises an air suction port, a fan, an upper floating ring, a gas pressure balance hole, a gas collecting box and a fixing ring, the fan is installed at the top end of the inside of the gas collecting box to ensure that the collected gas is uniformly mixed, the air suction port is formed in the top end of the gas collecting box, the gas pressure balance hole is installed in the side portion of the gas collecting box to ensure that the internal gas pressure and the external gas pressure are consistent, the fixing ring is installed outside the gas collecting box to fix the gas collecting chamber on the liquid level of the reaction tank through a rope, the upper floating ring is installed outside the gas collecting box, and the air suction port is formed in the top of the gas collecting box to extract a gas sample to perform subsequent analysis.
Furthermore, the dehumidification chambers, the PLC, the gas phase nitrous oxide analyzer, the liquid phase nitrous oxide measurement host and the computer are all arranged indoors, the number of the dehumidification chambers is multiple, the gas flow meter is respectively communicated with the gas inlets of the dehumidification chambers, and the gas phase nitrous oxide analyzer is respectively communicated with the gas outlets of the dehumidification chambers.
Furthermore, during the operation of the device, a plurality of dehumidification chambers are alternately used, and one and only one of the dehumidification chambers are used for dehumidification at the same time.
Further, the dehumidifying chamber is internally provided with a allochroic silica gel drying agent, so that the relative humidity of the gas to be measured is reduced from 90% RH to 42% RH-55% between RH; when the humidity sensor in the dehumidification chamber displays that the relative humidity value is higher than 55% RH, the current path of the dehumidification chamber is closed immediately, and valves of the electric heating wire, the exhaust fan and the vent are opened to dry the allochroic silica gel desiccant, so that the dehumidification function of the allochroic silica gel desiccant is recovered, the generated water vapor is discharged, and meanwhile, the path of the other dehumidification chamber is opened to continue dehumidifying the gas to be detected.
Furthermore, the data of the humidity sensor can be transmitted to the PLC in real time, and the electric heating wire, the exhaust fan, the valve of the vent and the air inlet and outlet of the dehumidifying chamber are controlled to be opened and closed by the PLC.
Furthermore, a gas sampling bag is connected to the gas outlet of the gaseous nitrous oxide analyzer to collect a gas sample, and the nitrous oxide isotope analyzer is used for further analyzing the generation path of nitrous oxide.
A method for measuring nitrous oxide emission of a sewage treatment plant comprises the following steps:
step 1: fixing a nitrous oxide microelectrode below the liquid level of effluent of the reaction tank, fixing a gas collection chamber above the liquid level of the reaction tank, and determining the connection of pipelines and lines of each part of the device; the concentration of the liquid-phase nitrous oxide is measured through the fixed nitrous oxide microelectrode and the liquid-phase nitrous oxide measurement host, and the gas collection chamber is used for extracting a gas sample to detect the concentration of the gas-phase nitrous oxide;
and 2, step: reading the concentration of liquid-phase nitrous oxide in the reaction tank by using a computer;
and 3, step 3: determining a concentration of gaseous nitrous oxide by a gaseous nitrous oxide analyzer;
and 4, step 4: after the measurement device was connected, the gas flow meter was set to 1-5L/min, the gas pump was turned on, and the gas collected in the gas collection chamber was first introduced into the dehumidification chamber to reduce the gas humidity to 42-55% RH, and then introduced into the gas phase nitrous oxide analyzer for concentration measurement.
Further, the determination steps of the gaseous phase nitrous oxide in the reaction tank are as follows: and setting the gas flow meter to be 1-5L/min, opening the gas pump, pumping a gas sample in the gas collection chamber into the dehumidification chamber to reduce the humidity of the gas, and then feeding the gas sample into the gas phase nitrous oxide analyzer for concentration determination.
Compared with the prior art, the invention has the following beneficial effects:
the invention has the advantages that the dehumidification chamber is arranged to obviously reduce the humidity of the gas to be detected, the interference of water vapor on the detection of the nitrous oxide is eliminated, the measurement accuracy is improved, meanwhile, the PLC is utilized to realize the on-line continuous monitoring of the gaseous phase and the liquid phase nitrous oxide in the reaction tank, the automation degree is high, the labor cost is saved, and a reliable data basis is provided for estimating the emission and the yield of the nitrous oxide in the sewage treatment plant.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic structural diagram of the present invention.
FIG. 2 is a schematic cross-sectional view of a gas collection chamber.
FIG. 3 is a schematic view of a flow and an apparatus for measuring gaseous phase nitrous oxide.
The device comprises a reaction tank 1, a gas collecting chamber 2, an air pumping port 2.1, a fan 2.2, an upper floating ring 2.3, an air pressure balancing hole 2.4, a gas collecting box 2.5, a fixing ring 2.6, an air pump 3, a gas flowmeter 4, a dehumidification chamber 5, a ventilation port 5.1, an exhaust fan 5.2, a thermometer 5.3, a allochroic silica gel desiccant 5.4, an observation window 5.5, a porous tray 5.6, an electric heating wire 5.7, a humidity sensor 5.8, a PLC 6, a gaseous nitrous oxide analyzer 7, an air outlet 8, a nitrous oxide microelectrode 9, a nitrous oxide measuring host 10-liquid phase measuring host and a computer 11.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1, the present invention provides a device for measuring nitrous oxide emissions from a sewage treatment plant. The measuring device comprises a reaction tank 1, a gas collecting chamber 2, a gas pump 3, a gas flowmeter 4, a dehumidifying chamber 5, a PLC (programmable logic controller) 6, a gas phase nitrous oxide analyzer 7, a nitrous oxide microelectrode 9, a liquid phase nitrous oxide measuring host 10 and a computer 11.
As shown in fig. 2, the gas collection chamber 2 is composed of a gas collection box 2.5 and an upper floating ring 2.3, a gas pressure balance hole 2.4 is installed on the lateral portion of the gas collection box 2.5 to ensure the uniformity of internal and external gas pressures, a fan 2.2 is installed on the top end of the inner portion to ensure the uniform mixing of collected gas, a fixing ring 2.6 is installed on the outer portion, the gas collection box 2.5 is fixed on the liquid level of the reaction tank 1 through the fixing ring 2.6 by using a rope, an air suction opening 2.1 is formed in the top end of the gas collection box to extract a gas sample for subsequent analysis, and the fan 2.2 is a small fan.
In this embodiment, the upper floating ring 2.3 has good air tightness, is made of light material, and is adhered to the outer side of the gas collection box 2.5 to ensure that the gas collection box 2 can float on the liquid surface.
In this embodiment, the lower portion of the gas collection box 2.5 is a cylindrical body, and the upper portion is a conical body, forming an inner cavity for collecting gas.
As shown in fig. 3, a gas inlet is provided at the top end of the dehumidification chamber 5, a gas outlet is provided at the bottom end of the dehumidification chamber 5, the gas inlet of the dehumidification chamber 5 is communicated with the gas flow meter 4, and the gas outlet is communicated with the gaseous nitrous oxide analyzer 7. 5 tops of dehumidification room are equipped with vent 5.1, air discharge fan 5.2 and thermometer 5.3, and the bottom is equipped with humidity transducer 5.8 and electric heating wire 5.7, and electric heating wire 5.7 top is equipped with porous tray 5.6, and color-changing silica gel drier 5.4 is placed to porous tray 5.6 top, 5 lateral parts of dehumidification room are equipped with observation window 5.5 and judge its dehumidification ability with the colour of observing color-changing silica gel drier 5.4 at any time.
In this embodiment, the number of the dehumidifying chambers 5 is plural, the gas inlets of the dehumidifying chambers 5 are respectively communicated with the gas flow meter 5, and the gas outlets of the dehumidifying chambers 5 are respectively communicated with the gaseous nitrous oxide analyzer 7.
In this embodiment, during the operation of the system, the plurality of dehumidifying chambers 5 are used alternately, and only one of the plurality of dehumidifying chambers 5 is used for dehumidifying at the same time.
In this embodiment, when the humidity sensor 5.8 of the dehumidification chamber 5 indicates that the relative humidity value is higher than 55% rh, the current path of the dehumidification chamber 5 is immediately closed, and the electric heating wire 5.7, the exhaust fan 5.2 and the vent 5.1 are opened to dry the allochroic silica gel desiccant 5.4, so that the dehumidification function is recovered, the generated water vapor is exhausted, and the path of the other dehumidification chamber is opened to continue dehumidifying the gas to be tested.
In this embodiment, the data of the humidity sensor 5.8 is transmitted to the PLC controller 6 in real time, and the electric heating wire 5.7, the exhaust fan 5.2, the valve of the vent 5.1, and the gas inlet and outlet of the dehumidification chamber 5 are controlled to be opened and closed by the PLC controller 6; the PLC is utilized to realize high automation, labor cost is saved, long-term continuous online monitoring on liquid-phase and gas-phase nitrous oxide in a reaction tank of a sewage treatment plant can be realized, a reliable data base is provided for estimating nitrous oxide emission of the sewage treatment plant, and the PLC has good practical significance and application prospect.
A method for measuring nitrous oxide emission of a sewage treatment plant comprises the following steps:
step 1: fixing a nitrous oxide microelectrode 9 below the liquid level of the effluent of the reaction tank 1, fixing a gas collection chamber 2 above the liquid level of the reaction tank 1, and determining the connection of pipelines and lines of each part of the device; the concentration of the liquid-phase nitrous oxide is measured through the fixed nitrous oxide microelectrode 9 and the liquid-phase nitrous oxide measuring host 10, and the gas collecting chamber 2 is used for extracting a gas sample to detect the concentration of the gas-phase nitrous oxide;
step 2: reading the concentration of the liquid-phase nitrous oxide in the reaction cell 1 by using a computer 11;
and step 3: the concentration of gaseous nitrous oxide is measured by a gaseous nitrous oxide analyzer 7;
and 4, step 4: after the measurement apparatus is connected, the gas flow meter 4 is set to 1-5L/min, the gas pump 3 is turned on, and the gas collected in the gas collection chamber 2 first enters the dehumidification chamber 5 to reduce the gas humidity to 42-55% RH, and then enters the gas phase nitrous oxide analyzer 7 to perform concentration measurement.
Example 1:
this example is an example of nitrous oxide emission measurement in a certain sewage treatment plant. According to previous researches, nitrous oxide emission in a mainstream process of a sewage treatment plant is mainly achieved through two ways: the gaseous phase nitrous oxide escapes from the water surface along with aeration and the dissolved nitrous oxide enters the environment along with effluent, so the embodiment estimates the nitrous oxide emission of the sewage treatment plant by continuously detecting the gaseous phase nitrous oxide in the aeration tank and the liquid phase nitrous oxide in the effluent on line. The nitrous oxide microelectrode 9 is fixed below the liquid level of the effluent, the concentration of liquid-phase nitrous oxide in the effluent is directly measured through the nitrous oxide microelectrode 9 and the liquid-phase nitrous oxide measuring host 10, and the measured concentration value is read on the computer 11. The process of measuring the gas phase oxidation sub-concentration in the aeration tank is as follows: the gas collected by the gas collecting chamber 2 above the liquid level of the aeration reaction tank is pumped by the gas pump 3, and the gas flow meter 4 is adjusted to be 1-5L/min. The gas to be detected enters the first dehumidification chamber 5 through a1 and a2 of the three-way valve, the humidity of the gas to be detected after the moisture is absorbed by the allochroic silica gel drying agent is reduced to 42-55% RH, the gas to be detected enters the gas phase nitrous oxide analyzer 7 through b1 and b3 of the three-way valve for concentration detection, and the gas after the concentration detection is discharged from the gas outlet 8. The allochroic silicagel desiccant 5.4 in the first dehumidification chamber 5 gradually loses the dehumidification capacity along with the extension of the dehumidification time, when the humidity sensor 5.8 shows that the relative humidity of the gas to be detected is higher than 55% RH, the PLC controller 6 automatically closes the a2 path and the b1 path, opens the electric heating wire 5.7, the exhaust fan 5.2 and the first valve of the vent 5.1 to dry the allochroic silicagel desiccant, recovers the dehumidification function, exhausts the generated water vapor, simultaneously opens the a3 path and the b2 path, enables the gas to be detected to enter the second dehumidification chamber 5 to continue to dehumidify the gas to be detected, and the dehumidified gas to be detected enters the gas phase nitrous oxide analyzer 7 through the b2 and the b3 of the three-way valve to detect the concentration. And (3) processing and summing the obtained continuous concentration numerical values of the gaseous phase nitrous oxide in the aeration tank and the effluent liquid phase nitrous oxide in a period of time, so as to estimate the nitrous oxide emission of the sewage treatment plant.
By arranging the dehumidification chamber, the interference of water vapor on the detection of the nitrous oxide is avoided, the continuous online monitoring of the nitrous oxide in the sewage treatment plant is realized by utilizing the PLC 6, dynamic nitrous oxide emission data which change along with the change of the operation period can be obtained, and a reliable data base is provided for the estimation of the nitrous oxide yield of the sewage treatment plant and the establishment of emission reduction measures.
Example 2:
this example is an example of the determination of the nitrous oxide yield of different treatment units of a certain sewage treatment plant. This example is substantially the same as example 1 except that the nitrous oxide microelectrode 9 and the gas collection chamber 2 are disposed in the same processing unit. The placement and flow of the assay device is shown in FIGS. 1-3. And (3) processing and summing the continuous concentration values of the gaseous phase nitrous oxide and the liquid phase nitrous oxide in a certain processing unit within a certain period of time, so as to estimate the nitrous oxide yield of the processing unit.
By simply adjusting the arrangement positions of the nitrous oxide microelectrode 9 and the gas collecting chamber 2, the nitrous oxide yield of different treatment units in the sewage treatment plant can be obtained, the analysis of the main source of nitrous oxide and the investigation of the carbon footprint of the sewage treatment plant are facilitated, and the method has important practical significance and application prospect.
Example 3:
the embodiment is an embodiment of nitrous oxide accumulation measurement of an anoxic pond of a certain sewage treatment plant. Basically the same as in example 1, except that the vapor phase nitrous oxide measurement device was not used, the nitrous oxide microelectrodes 9 were disposed just below the liquid surface of the anoxic tank. The concentration of the liquid phase nitrous oxide in the anoxic pond is measured through the nitrous oxide microelectrode 9 and the liquid phase nitrous oxide measurement host machine 10, and the measured concentration value is read on the computer 11. According to the obtained long-term continuous data, the accumulation amount of the nitrous oxide in the anoxic pond and the dynamic rule of the nitrous oxide, which changes along with the change of the operation period, can be analyzed.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
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 (9)
1. The device for measuring the nitrous oxide emission of the sewage treatment plant is characterized by comprising a reaction tank (1), a gas collecting chamber (2), an air pump (3), a gas flow meter (4), a dehumidifying chamber (5), a PLC (programmable logic controller) (6), a gas phase nitrous oxide analyzer (7), a nitrous oxide microelectrode (9), a liquid phase nitrous oxide measuring host (10) and a computer (11);
the device comprises a reaction tank (1), a gas collecting chamber (2), a gas flow meter (4), a dehumidifying chamber (5), a gas outlet of the dehumidifying chamber (5), a gas phase nitrous oxide analyzer (7), a PLC (programmable logic controller) controller (6), a gas collecting chamber (2), a gas pump (3), a gas flow meter (4), a gas inlet of the dehumidifying chamber (5), a gas outlet (8), a gas-phase nitrous oxide analyzer and a gas collecting chamber (2), wherein the gas collecting chamber (2) is fixed above the liquid level of the reaction tank (1) through a rope; the nitrous oxide microelectrode (9) is connected with a liquid phase nitrous oxide measuring host (10) in an interconnection mode, the liquid phase nitrous oxide measuring host (10) is electrically connected with a computer (11), and the nitrous oxide microelectrode (9) is arranged below the liquid level of the reaction tank (1).
2. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 1, characterized in that: dehumidification room (5) are including vent (5.1), air discharge fan (5.2), thermometer (5.3), color-changing silica gel drier (5.4), observation window (5.5), porous tray (5.6), electric heating wire (5.7) and humidity transducer (5.8), air discharge fan (5.2) is installed to vent (5.1) bottom, air discharge fan (5.2) below is provided with color-changing silica gel drier (5.4), porous tray (5.6) are installed to the bottom of color-changing silica gel drier (5.4), electric heating wire (5.7) are installed to the bottom of porous tray (5.6), the department of gas outlet of dehumidification room (5) installs humidity transducer (5.8), install observation window (5.5) except that dehumidification room (5), except that dehumidification room (5) internally mounted has thermometer (5.3).
3. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 1, characterized in that: the gas collection chamber (2) comprises an air suction opening (2.1), a fan (2.2), an upper floating ring (2.3), a gas pressure balance hole (2.4), a gas collection box (2.5) and a fixing ring (2.6), wherein the fan (2.2) is installed at the top end of the inside of the gas collection box (2.5) to ensure that the collected gas is uniformly mixed, the top end of the gas collection box (2.5) is provided with the air suction opening (2.1) for sucking a gas sample for subsequent analysis, the gas pressure balance hole (2.4) is installed at the side part of the gas collection box (2.5) to ensure that the internal and external gas pressures are consistent, the fixing ring (2.6) is installed outside the gas collection chamber (2) and used for fixing the gas collection chamber (2) on a reaction liquid level pool through a rope, and the upper floating ring (2.3) is installed outside the gas collection box (2.5).
4. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 2, characterized in that: dehumidification room (5), PLC controller (6), gaseous phase nitrous oxide analysis ware (7), liquid phase nitrous oxide measure host computer (10) and computer (11) all set up indoor, dehumidification room (5) quantity is a plurality of, gas flowmeter (4) communicate with the air inlet of a plurality of dehumidification rooms (5) respectively, gaseous phase nitrous oxide analysis ware (7) communicate with the gas outlet of a plurality of dehumidification rooms (5) respectively.
5. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 4, characterized in that: during the operation of the measuring device, the plurality of dehumidifying chambers (5) are used alternately, and only one of the plurality of dehumidifying chambers (5) is used for dehumidifying at the same time.
6. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 5, characterized in that: a chromophoric silica gel desiccant (5.4) is provided in the dehumidification chamber (5) to reduce the relative humidity of the gas to be measured from 90% RH to 42% RH-55% between RH; when the humidity sensor (5.8) in the dehumidification chamber (5) displays that the relative humidity value is higher than 55 percent RH, the current path of the dehumidification chamber (5) is closed immediately, and the electric heating wire (5.7), the exhaust fan (5.2) and the valve of the ventilation opening (5.1) are opened to dry the allochroic silica gel desiccant (5.4), so that the dehumidification function is recovered, the generated water vapor is exhausted, and simultaneously the path of the other dehumidification chamber (5) is opened to continue to dehumidify the gas to be tested.
7. The device for measuring nitrous oxide emission of sewage treatment plant according to claim 6, characterized in that: the data of the humidity sensor (5.8) are transmitted to the PLC controller (6) in real time, and the electric heating wire (5.7), the exhaust fan (5.2), the valve of the vent (5.1) and the passage of the gas inlet and outlet of the dehumidification chamber (5) are controlled to be opened and closed by the PLC controller (6).
8. A method for measuring nitrous oxide emission of a sewage treatment plant, which is realized by using the measuring device of any one of claims 1 to 7, and is characterized by comprising the following steps:
step 1: fixing a nitrous oxide microelectrode (9) below the liquid level of effluent of the reaction tank (1), fixing a gas collection chamber (2) above the liquid level of the reaction tank (1), and determining the connection of pipelines and lines of each part of the device; the concentration of the liquid-phase nitrous oxide is measured through a fixed nitrous oxide microelectrode (9) and a liquid-phase nitrous oxide measuring host (10), and a gas collecting chamber (2) is used for extracting a gas sample to detect the concentration of the gas-phase nitrous oxide;
step 2: reading the concentration of liquid-phase nitrous oxide in the reaction cell (1) by using a computer (11);
and step 3: determining the concentration of gaseous nitrous oxide by means of a gaseous nitrous oxide analyzer (7);
and 4, step 4: after the measurement device is connected, the gas flow meter (4) is set to 1-5L/min, the gas pump (3) is opened, and the gas collected in the gas collection chamber (2) first enters the dehumidification chamber (5) to reduce the gas humidity to 42-55% RH, and then enters the gas phase nitrous oxide analyzer (7) to perform concentration measurement.
9. The method for measuring nitrous oxide emission of sewage treatment plant according to claim 8, characterized in that the step of measuring gaseous phase nitrous oxide in the reaction tank (1) is as follows: the gas flow meter (4) is set to be 1-5L/min, the gas pump (3) is opened, the gas sample in the gas collection chamber (2) is pumped into the dehumidification chamber (5) to reduce the humidity of the gas, and then the gas sample enters the gas phase nitrous oxide analyzer (7) to be subjected to concentration measurement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210917287.9A CN115165994A (en) | 2022-08-01 | 2022-08-01 | Device and method for measuring nitrous oxide emission of sewage treatment plant |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210917287.9A CN115165994A (en) | 2022-08-01 | 2022-08-01 | Device and method for measuring nitrous oxide emission of sewage treatment plant |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115165994A true CN115165994A (en) | 2022-10-11 |
Family
ID=83477398
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210917287.9A Pending CN115165994A (en) | 2022-08-01 | 2022-08-01 | Device and method for measuring nitrous oxide emission of sewage treatment plant |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115165994A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116990089A (en) * | 2023-07-31 | 2023-11-03 | 珠海深圳清华大学研究院创新中心 | Monitoring device and method for directly discharging sewage greenhouse gases |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130076909A (en) * | 2011-12-29 | 2013-07-09 | 박승우 | Dehumidifying apparatus for recycle silica-gel using fan heating |
| CN104007235A (en) * | 2014-05-22 | 2014-08-27 | 河南师范大学 | Simulator for monitoring generation of nitrous oxide in process of aerobic biological treatment of sewage |
| CN104236954A (en) * | 2014-09-19 | 2014-12-24 | 北京工业大学 | Collection device for treating N2O on water level of treatment unit in sewage treatment plant and sampling method |
| CN109307729A (en) * | 2018-09-12 | 2019-02-05 | 中国原子能科学研究院 | Nitrous acid vapor liquid equilibrium assigned unit and method in a kind of measurement nitric acid solution |
| CN114609077A (en) * | 2022-03-07 | 2022-06-10 | 天津大学 | Device and method for measuring gas-phase methane in sewage pipe network |
-
2022
- 2022-08-01 CN CN202210917287.9A patent/CN115165994A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130076909A (en) * | 2011-12-29 | 2013-07-09 | 박승우 | Dehumidifying apparatus for recycle silica-gel using fan heating |
| CN104007235A (en) * | 2014-05-22 | 2014-08-27 | 河南师范大学 | Simulator for monitoring generation of nitrous oxide in process of aerobic biological treatment of sewage |
| CN104236954A (en) * | 2014-09-19 | 2014-12-24 | 北京工业大学 | Collection device for treating N2O on water level of treatment unit in sewage treatment plant and sampling method |
| CN109307729A (en) * | 2018-09-12 | 2019-02-05 | 中国原子能科学研究院 | Nitrous acid vapor liquid equilibrium assigned unit and method in a kind of measurement nitric acid solution |
| CN114609077A (en) * | 2022-03-07 | 2022-06-10 | 天津大学 | Device and method for measuring gas-phase methane in sewage pipe network |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116990089A (en) * | 2023-07-31 | 2023-11-03 | 珠海深圳清华大学研究院创新中心 | Monitoring device and method for directly discharging sewage greenhouse gases |
| CN116990089B (en) * | 2023-07-31 | 2024-03-12 | 珠海深圳清华大学研究院创新中心 | Monitoring device and method for directly discharging sewage greenhouse gases |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103389279B (en) | The device and method of sub-methyl blue spectrum analysis on-line checkingi water quality medium sulphide content concentration | |
| CN115165994A (en) | Device and method for measuring nitrous oxide emission of sewage treatment plant | |
| CN106198117B (en) | The in-site detecting device and measuring method of gas parameter | |
| CN206248652U (en) | Real-time in-situ water quality monitor | |
| CN105842725A (en) | Method for detecting specific activity of tritiated steam in air | |
| CN205719079U (en) | A kind of high-temperature gas humidity on-line measuring device | |
| CN201421449Y (en) | Device for measuring formaldehyde gas absorbed by plants real-timely and quantificationally | |
| CN113588739A (en) | Continuous arterial blood detection system | |
| CN108982770A (en) | Gas detection pretreatment system and gas online test method | |
| CN108490128A (en) | A kind of residual gas remove device | |
| CN107532978A (en) | The apparatus and method of detection pollution position, and computer readable recording medium storing program for performing | |
| CN210347252U (en) | Smoke and dust flue gas atmosphere detection device | |
| CN208488430U (en) | Gas on-line detecting system | |
| CN104297321B (en) | Intelligent detection device of hydrogen sulfide generated by sludge aerobic fermentation | |
| CN110632642A (en) | Rotary radioactive iodine monitoring system and method | |
| CN206460030U (en) | The integrated automonitor of city black and odorous water | |
| CN212459396U (en) | Device for preventing optical cavity ring-down closed-circuit flux analyzer from water inflow | |
| CN211576948U (en) | Automatic comprehensive smoke and dust tester | |
| CN207908482U (en) | A kind of residual gas remove device | |
| CN111551590A (en) | Full-automatic coal rock gas desorption and resistivity measuring device | |
| CN212341174U (en) | Large-traffic tail gas analysis device of binary channels for microorganism high density culture | |
| CN218725781U (en) | Gas monitoring and detecting device of blast furnace gas fine desulfurization system | |
| CN219608868U (en) | Online multi-gas detection device | |
| CN110186821A (en) | A kind of Performance Test System of indoor air quality sensor under different humidity | |
| CN220104854U (en) | Soil respiration intensity monitoring equipment for urban green land |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |