CN209311403U - Gas-chromatography non-methane total hydrocarbons detection device - Google Patents
Gas-chromatography non-methane total hydrocarbons detection device Download PDFInfo
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- CN209311403U CN209311403U CN201822016235.6U CN201822016235U CN209311403U CN 209311403 U CN209311403 U CN 209311403U CN 201822016235 U CN201822016235 U CN 201822016235U CN 209311403 U CN209311403 U CN 209311403U
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Abstract
The disclosure provides a kind of gas-chromatography non-methane total hydrocarbons detection device, comprising: air admission unit, status toggle unit, carrier gas unit, methane separation element and detection unit;The air admission unit, for inputting test sample gas to be checked;The carrier gas unit is connected to the status toggle unit for being set to sample gas detection path, moves in sample gas detection path for carrying the test sample gas to be checked;The status toggle unit, one end are connect with the air admission unit, and the other end is connect with the detection unit, and for switching the working condition of the methane separation element, realization switches between CH_4 detection state and non-methane total hydrocarbons detecting state;When switching to CH_4 detection state, the detection unit is used to detect the methane content in the test sample gas to be checked;When switching to non-methane total hydrocarbons detecting state, the detection unit is used to detect the non-methane total hydrocarbons content in the test sample gas to be checked.The disclosure integrally realizes that structure is simple, and testing result is accurate, fast response time.
Description
Technical field
The disclosure belongs to field of gas detection, is related to a kind of gas-chromatography non-methane total hydrocarbons detection device.
Background technique
Non-methane total hydrocarbons (NMHC) typically refers to all volatilizable hydrocarbons in addition to methane.It is non-in atmosphere
When methane total hydrocarbon is more than a certain concentration, at human health, moreover it is possible to generate chemical fumes, be caused to environment and the mankind great
Harm.The emission concentration standard of the non-methane total hydrocarbons in China's " discharge standard of air pollutants " is 120mg/m3.Non-methane
Catalytic oxidation and chromatography are broadly divided on total hydrocarbon (NMHC) testing principle.Chromatography determination non-methane total hydrocarbons typically refer to through
Cross the summation of organic gas compound of the chromatographic isolation on the flame ionization ditector of gas-chromatography other than methane.
Catalytic oxidation and the chromatographic main distinction are that catalysis method divides methane by the organic matter other than catalytic methane
Analysis.
Detection for non-methane total hydrocarbons, currently used method have 3 road nitrogen of twin columns bivalve dual detector, twin columns single valve
2 road nitrogen of dual detector or twin columns single valve list detector first detect the content of total hydrocarbon, then detect methane content, the difference of the two
Value is exactly non-methane total hydrocarbons, either that method, all there is at high cost, complicated defect.And because different detections
The difference of device performance will cause testing result inaccuracy.
Utility model content
To overcome the problems in correlation technique, the disclosure provides a kind of gas-chromatography non-methane total hydrocarbons detection device,
It is characterised by comprising: a kind of non-methane total hydrocarbons detection device characterized by comprising air admission unit, status toggle unit,
Carrier gas unit, methane separation element and detection unit;
The air admission unit, for inputting test sample gas to be checked;
The carrier gas unit is connected to the status toggle unit for being set to sample gas detection path, described for carrying
Test sample gas to be checked moves in sample gas detection path;
The status toggle unit, one end are connect with the air admission unit, and the other end is connect with the detection unit, are used for
Switch the working condition of the methane separation element, realization is cut between CH_4 detection state and non-methane total hydrocarbons detecting state
It changes;
When switching to CH_4 detection state, the methane that the detection unit is used to detect in the test sample gas to be checked contains
Amount;
When switching to non-methane total hydrocarbons detecting state, the detection unit is non-in the test sample gas to be checked for detecting
Methane total hydrocarbon content.
It further, further include dosing unit, the dosing unit is set in sample gas detection path, for quantitative
Obtain the test sample gas to be checked.
Further, described when switching to CH_4 detection state, the detection unit is for detecting the test sample to be checked
Methane content in gas includes:
The status toggle unit is eight logical sampling valves;
The eight logical sampling valve switches to the first working condition, and the dosing unit is accessed the sample gas and detects path,
So that the carrier gas unit is connect with the dosing unit, the methane separation element and the detection unit respectively, by institute
It states test sample gas to be checked and is transported to the detection unit.
Further, described when switching to non-methane total hydrocarbons detecting state, the detection unit for detect it is described to
Detection sample gas in non-methane total hydrocarbons content include:
The eight logical sampling valve switches to the second working condition, so that the carrier gas unit is through the dosing unit blowback institute
Methane separation element is stated, the test sample gas to be checked is transported to the detection unit.
Further, the methane separation element is methane chromatographic column.
Further, described when switching to CH_4 detection state, the detection unit is for detecting the test sample to be checked
Methane content in gas includes:
The status toggle unit is two three-way electromagnetic valves;
Two three-way electromagnetic valve switches to the first working condition, and the methane separation element is accessed to the sample gas and is detected
Path, so that the methane separation element, the carrier gas unit and the dosing unit are sequentially connected, by the test sample to be checked
Gas is transported to the detection unit.
Further, described when switching to non-methane total hydrocarbons detecting state, the detection unit for detect it is described to
Detection sample gas in non-methane total hydrocarbons content include:
Two three-way electromagnetic valve switches to the second working condition, so that the carrier gas unit conveys the test sample gas to be checked
To the detection unit.
Further, which is characterized in that the methane separation element is non-methane total hydrocarbons catalytic converter.
Further, the non-methane total hydrocarbons catalytic converter is hollow circular-tube, is of a straight line type or screw type, outside
Heater is wrapped up, inside is filled with nickel-base catalyst, and the non-methane total hydrocarbons catalytic converter is heated to 240 by the heater
℃-260℃。
It further, further include heating unit, for heating the detection device in non-methane total hydrocarbons detection process.
The technical scheme provided by this disclosed embodiment can include the following benefits: the disclosure is switched single using state
Member switches different flow paths under different working conditions, uses a detection unit, a methane separation element, a carrier gas
The detection of non-methane total hydrocarbons can be realized in unit.Whole to realize that structure letter is answered, testing result is accurate, and fast response time, and one
As be less than 60s can be obtained testing result.
It should be understood that above general description and following detailed description be only it is exemplary and explanatory, not
The disclosure can be limited.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of non-methane total hydrocarbons detection device shown in one exemplary embodiment of the disclosure;
Fig. 2 is an a kind of working state structure of non-methane total hydrocarbons detection device shown in one exemplary embodiment of the disclosure
Figure;
Fig. 3 is an a kind of working state structure of non-methane total hydrocarbons detection device shown in one exemplary embodiment of the disclosure
Figure;
Fig. 4 is a kind of structural schematic diagram of non-methane total hydrocarbons detection device shown in one exemplary embodiment of the disclosure.
Specific embodiment
Example embodiments are described in detail here, and the example is illustrated in the accompanying drawings.Following description is related to
When attached drawing, unless otherwise indicated, the same numbers in different drawings indicate the same or similar elements.Following exemplary embodiment
Described in embodiment do not represent all implementations consistent with this disclosure.On the contrary, they be only with it is such as appended
The example of the consistent device and method of some aspects be described in detail in claims, the disclosure.
It is only to be not intended to be limiting the disclosure merely for for the purpose of describing particular embodiments in the term that the disclosure uses.
The "an" of the singular used in disclosure and the accompanying claims book, " described " and "the" are also intended to including majority
Form, unless the context clearly indicates other meaning.It is also understood that term "and/or" used herein refers to and wraps
It may be combined containing one or more associated any or all of project listed.
It will be appreciated that though various information, but this may be described using term first, second, third, etc. in the disclosure
A little information should not necessarily be limited by these terms.These terms are only used to for same type of information being distinguished from each other out.For example, not departing from
In the case where disclosure range, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as
One information.Depending on context, word as used in this " if " can be construed to " ... when " or " when ...
When " or " in response to determination ".
As shown in Figure 1, a kind of non-methane total hydrocarbons detection device 100 shown according to an exemplary embodiment, feature exists
In, comprising:
Air admission unit 1, status toggle unit 2, carrier gas unit 3, methane separation element 4 and detection unit 5;
The air admission unit 1, for inputting test sample gas to be checked;
The carrier gas unit 3 is connected to the status toggle unit 2 for being set to sample gas detection path, for carrying
Test sample gas to be checked is stated to move in sample gas detection path;
The status toggle unit 2, one end connect 1 with the air admission unit, and the other end is connect with the detection unit 5,
For switching the working condition of the methane separation element 4, realize CH_4 detection state and non-methane total hydrocarbons detecting state it
Between switch;
When switching to CH_4 detection state, the methane that the detection unit 5 is used to detect in the test sample gas to be checked contains
Amount;
When switching to non-methane total hydrocarbons detecting state, the detection unit 5 is for detecting in the test sample gas to be checked
Non-methane total hydrocarbons content.
According to one embodiment of the disclosure, as shown in Figure 1, non-methane total hydrocarbons detection device 100 includes air admission unit 1, state
Switch unit 2, carrier gas unit 3, methane separation element 4 and detection unit 5 are being switched to by the control of status toggle unit 2
When CH_4 detection state, flow path is switched to CH_4 detection state by detection device 100, to the methane content in sample gas to be detected
Detection;When switching to non-methane total hydrocarbons detecting state, flow path is switched to non-methane total hydrocarbons detecting state by detection device 100,
To the non-methane total hydrocarbons content detection in sample gas.
It further, further include dosing unit 6, the dosing unit 6 is set in sample gas detection path, for fixed
Amount obtains the test sample gas to be checked.
According to one embodiment of the disclosure, as shown in Figure 1, detection device 100 can also include dosing unit 6, dosing unit 6
Setting is in sample gas detection path, for quantitatively obtaining test sample gas to be checked, it is ensured that the accurate and timeliness of detection.Such as Fig. 2
Shown, dosing unit 6 is linked into sample gas detection path, for quantitatively obtaining test sample gas to be checked.It is of course also possible to be not provided with determining
Unit 6 is measured, guarantees a certain number of test sample gas to be checked by controlling the amount of air inlet.
Further, described when switching to CH_4 detection state, the detection unit 5 is for detecting the test sample to be checked
Methane content in gas includes:
The status toggle unit 2 is eight logical sampling valves 201;
The eight logical sampling valve 201 switches to the first working condition, and the dosing unit 6 is accessed the sample gas and detects road
Diameter, so that the carrier gas unit 3 connects with the dosing unit 6, the methane separation element 4 and the detection unit 5 respectively
It connects, the test sample gas to be checked is transported to the detection unit 5.
According to one embodiment of the disclosure, as shown in Fig. 2, giving a kind of structure of detection device 100.Wherein, state is cut
Changing unit 2 is eight logical sampling valves 201.As shown in Fig. 2, eight logical sampling valves 201 have 8 accesses, each access is adjacent thereto
One access ventilation connection, is isolated with its another adjacent lanes, and eight logical sampling valves 201 realize that flow path is cut by the operation such as rotation
It changes, to switch under different working conditions.
The first step of CH_4 detection state is shown in Fig. 2, dosing unit 6 is connect with air admission unit 1, by dosing unit
Quantitative test sample gas to be checked is full of in 6.Flow path of the eight logical sampling valves 201 that Fig. 3 is shown in CH_4 detection state, i.e., the first work
State.In this state, carrier gas unit 3 is linked into sample gas detection path, is sequentially connected dosing unit 6, methane separation element 4
With detection unit 5.Under the carrying of carrier gas nitrogen, the test sample gas to be checked in dosing unit 6 is admitted to methane separation element 4, first
Methane gas in sample gas is isolated sample gas by alkane separative unit 4, enters detection unit 5 along flow path, detection unit 5 is
Fid detector detects the content of methane in the sample gas sent.
Further, described when switching to non-methane total hydrocarbons detecting state, the detection unit 5 for detect it is described to
Detection sample gas in non-methane total hydrocarbons content include:
The eight logical sampling valve 201 switches to the second working condition, so that the carrier gas unit 3 is through the dosing unit 6
The test sample gas to be checked is transported to the detection unit by methane separation element 4 described in blowback.
Further, the methane separation element 4 is methane chromatographic column 401.
As shown in Fig. 2, eight logical sampling valves 201 switch to non-methane total hydrocarbons detecting state, by 4 (i.e. first of methane separation element
Alkane chromatographic column 401) flow path switching, carrier gas unit 3 carry dosing unit 6 in the remaining test sample gas to be checked for having separated methane into
Enter into detection unit 5, detects the non-methane total hydrocarbons content in the sample gas.
It further, further include heating unit, for heating the detection device in non-methane total hydrocarbons detection process.
In accordance with an embodiment of the present disclosure, in order to guarantee going on smoothly for detection, while accelerating to detect speed, can also be arranged
Heating unit (not shown), the heating unit are added in entire detection process for non-methane total hydrocarbons detection device 100
Heat guarantees 100 bulk temperature of non-methane total hydrocarbons detection device in a reasonable range of reaction temperature, it is ensured that entire detection process
Smoothly effectively carry out.
According to an embodiment of the disclosure, adoption status switch unit switches flow path, realize using a detection unit,
The measurement of non-methane total hydrocarbons can be completed in one methane separation element, a carrier gas unit.Apparatus structure is simple, highly reliable,
The response difference of bivalve dual detector band is avoided, testing result is more acurrate, and save the cost, and the detection used time is short.
It is further, described when switching to CH_4 detection state according to another embodiment of the disclosure, the detection unit
5 include: for the methane content that detects in the test sample gas to be checked
The status toggle unit 2 is two three-way electromagnetic valves 202;
Two three-way electromagnetic valve 202 switches to the first working condition, and the methane separation element 4 is accessed to the sample gas
Path is detected, so that the methane separation element 4, the carrier gas unit 3 and the dosing unit 6 are sequentially connected, it will be described
Test sample gas to be checked is transported to the detection unit 5.
As shown in figure 4, giving a kind of structure of detection device 100.Wherein, status toggle unit 2 is two three-way electromagnetic valves
202.As shown in figure 4, arbitrarily connecting two-way flow path all the way may be implemented in two three-way electromagnetic valves 202, thus realize that flow path switches,
Realization switches under different working conditions.
Two three-way electromagnetic valves 202 connect the first branch where methane separation element 4 in Fig. 4, that is, have been switched to the first work
State.In this state, methane separation element 4, the carrier gas unit 3 and the dosing unit 6 are sequentially connected, test sample to be checked
Gas separates methane gas after methane separation element 4, carries through carrier gas (nitrogen), into quantitative list 6, finally enters
Into detection unit 5, detection unit 5 detects the methane content in sample gas.
Further, described when switching to non-methane total hydrocarbons detecting state, the detection unit 5 for detect it is described to
Detection sample gas in non-methane total hydrocarbons content include:
Two three-way electromagnetic valve 202 switches to the second working condition, so that the carrier gas unit 3 is by the test sample gas to be checked
It is transported to the detection unit 5.
As shown in figure 4, two three-way electromagnetic valves 202 connect second branch, methane separation element 4 is picked out into sample gas detection path,
It has been switched to the second working condition.In this state, the carrier gas of carrier gas unit 3 carries test sample gas to be checked and enters dosing unit
It in 6, enters finally into detection unit 5, detection unit 5 detects the total hydrocarbon content in sample gas, and methane will be subtracted in total hydrocarbon content
Content obtains non-methane total hydrocarbons content.
Further, the methane separation element 4 is non-methane total hydrocarbons catalytic converter 402.
Further, the non-methane total hydrocarbons catalytic converter 402 is hollow circular-tube, is of a straight line type or screw type,
Outside package heater, inside are filled with nickel-base catalyst, and the heater heats the non-methane total hydrocarbons catalytic converter
To 240 DEG C -260 DEG C.
In accordance with an embodiment of the present disclosure, methane separation element 4 can be non-methane total hydrocarbons catalytic converter 402, the non-first
Alkane total hydrocarbon catalytic converter 402 is hollow circular-tube, and hollow circular-tube is linear type or spiral helicine bend pipe, and outer wall is by heater
Package, and heater includes temperature sensor and controllable temperature module, and the inside of the hollow circular-tube is filled with nickel-base catalyst, this
Catalyst can be oxidized to other organic gas other than methane carbon dioxide and water at 240 DEG C -260 DEG C, and first
Alkane itself does not change.
It further, further include heating unit, for heating the detection device in non-methane total hydrocarbons detection process.
In accordance with an embodiment of the present disclosure, in order to guarantee going on smoothly for detection, while accelerating to detect speed, can also be arranged
Heating unit (not shown), the heating unit are added in entire detection process for non-methane total hydrocarbons detection device 100
Heat guarantees 100 bulk temperature of non-methane total hydrocarbons detection device in a reasonable range of reaction temperature, it is ensured that entire detection process
Smoothly effectively carry out.
In accordance with an embodiment of the present disclosure, adoption status switch unit switches flow path, realizes using detection unit, one
The measurement of non-methane total hydrocarbons can be completed in a methane separation element, a carrier gas unit.Apparatus structure is simple, highly reliable, keeps away
The response difference of bivalve dual detector band is exempted from, testing result is more acurrate, and save the cost, and the response time is less than 60s.
The foregoing is merely the preferred embodiments of the disclosure, not to limit the disclosure, all essences in the disclosure
Within mind and principle, any modification, equivalent substitution, improvement and etc. done be should be included within the scope of disclosure protection.
Claims (10)
1. a kind of non-methane total hydrocarbons detection device characterized by comprising air admission unit, status toggle unit, carrier gas unit,
Methane separation element and detection unit;
The air admission unit, for inputting test sample gas to be checked;
The carrier gas unit is connected to the status toggle unit for being set to sample gas detection path, described to be checked for carrying
Test sample gas moves in sample gas detection path;
The status toggle unit, one end are connect with the air admission unit, and the other end is connect with the detection unit, for switching
The working condition of the methane separation element, realization switch between CH_4 detection state and non-methane total hydrocarbons detecting state;
When switching to CH_4 detection state, the detection unit is used to detect the methane content in the test sample gas to be checked;
When switching to non-methane total hydrocarbons detecting state, the detection unit is used to detect the non-methane in the test sample gas to be checked
Total hydrocarbon content.
2. detection device according to claim 1, which is characterized in that it further include dosing unit, the dosing unit setting
In sample gas detection path, for quantitatively obtaining the test sample gas to be checked.
3. detection device according to claim 2, which is characterized in that it is described when switching to CH_4 detection state, it is described
Detection unit is used for the methane content that detects in the test sample gas to be checked
The status toggle unit is eight logical sampling valves;
The eight logical sampling valve switches to the first working condition, and the dosing unit is accessed the sample gas and detects path, so that
The carrier gas unit is connect with the dosing unit, the methane separation element and the detection unit respectively, will it is described to
Detection sample gas is transported to the detection unit.
4. detection device according to claim 3, which is characterized in that described to switch to non-methane total hydrocarbons detecting state
When, the non-methane total hydrocarbons content that the detection unit is used to detect in the test sample gas to be checked includes:
The eight logical sampling valve switches to the second working condition, so that the carrier gas unit is through first described in the dosing unit blowback
The test sample gas to be checked is transported to the detection unit by alkane separative unit.
5. detection device described in any one of -4 according to claim 1, which is characterized in that the methane separation element is methane
Chromatographic column.
6. detection device according to claim 2, which is characterized in that it is described when switching to CH_4 detection state, it is described
Detection unit is used for the methane content that detects in the test sample gas to be checked
The status toggle unit is two three-way electromagnetic valves;
Two three-way electromagnetic valve switches to the first working condition, and the methane separation element is accessed to the sample gas and detects road
Diameter, so that the methane separation element, the carrier gas unit and the dosing unit are sequentially connected, by the test sample gas to be checked
It is transported to the detection unit.
7. detection device according to claim 6, which is characterized in that described to switch to non-methane total hydrocarbons detecting state
When, the non-methane total hydrocarbons content that the detection unit is used to detect in the test sample gas to be checked includes:
Two three-way electromagnetic valve switches to the second working condition, so that the test sample gas to be checked is transported to institute by the carrier gas unit
State detection unit.
8. according to claim 1, detection device described in any one of 2,6,7, which is characterized in that the methane separation element is
Non-methane total hydrocarbons catalytic converter.
9. detection device according to claim 8, which is characterized in that the non-methane total hydrocarbons catalytic converter is open circles
Pipe, is of a straight line type or screw type, external package heater, inside are filled with nickel-base catalyst, and the heater will be described
Non-methane total hydrocarbons catalytic converter is heated to 240 DEG C -260 DEG C.
10. detection device described in any one of -4,6,7 according to claim 1, which is characterized in that further include heating unit, use
In heating the detection device in non-methane total hydrocarbons detection process.
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CN109270183A (en) * | 2018-12-03 | 2019-01-25 | 华电智控(北京)技术有限公司 | Gas-chromatography non-methane total hydrocarbons detection device |
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