CN111624273A - Method for collecting light hydrocarbons in natural gas in laboratory, online circulation system and application - Google Patents
Method for collecting light hydrocarbons in natural gas in laboratory, online circulation system and application Download PDFInfo
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Abstract
The invention provides a method for collecting light hydrocarbons in natural gas in a laboratory, an online circulation system and application, and relates to the field of gas geochemical analysis, wherein the method comprises the steps that natural gas repeatedly flows through a pipeline provided with a molecular sieve in a vacuum circulation system, so that the light hydrocarbons in the natural gas are enriched in the molecular sieve; heating the molecular sieve enriched with light hydrocarbon in a vacuum circulating system, and collecting the light hydrocarbon released by the molecular sieve; wherein the light hydrocarbon is C5 hydrocarbon, C6 hydrocarbon, C7 hydrocarbon and C8 hydrocarbon, and the invention has the advantages of low cost, high light hydrocarbon content and low cost
Recycle systems for molecular sieves, i.e. obtaining pure C from natural gas with very low light hydrocarbon content5‑C8The method is simple and the cost is lowLow cost, simple operation and high obtaining efficiency.
Description
Technical Field
The invention relates to the field of gas geochemical analysis, in particular to a method and a system for collecting light hydrocarbon in natural gas.
Background
Light hydrocarbon (C)5-C8) The natural gas is one of the important components of natural gas, contains extremely important and abundant geochemical information, and light hydrocarbon geochemical indexes can be used for determining the maturity of the natural gas, identifying the gas reservoir which is subjected to water washing or biodegradation, tracing the source of the natural gas and dividing the cause type of the natural gas.
The crude oil sample contains a large amount of volatile light hydrocarbon components, so that the light hydrocarbon components can be analyzed by using gas chromatography or high performance liquid chromatography; however, the content of light hydrocarbon components in natural gas is very low, particularly the content of methane in dry gas reaches more than 95%, and other hydrocarbon components are very little, so that during gas chromatography detection, only a few components such as methane, ethane and the like, namely light hydrocarbon components (C)5-C8) The content cannot be detected because it does not reach the chromatographic detection limit. Due to the limitation of analysis technology, the scientific research on light hydrocarbon components in natural gas is slow and inferior to the research work on light hydrocarbon in crude oil and hydrocarbon source rocks, and the gas-oil-source comparison work in geological science is hindered. Therefore, how to accurately and conveniently analyze the trace light hydrocarbon in the natural gas by using the gas chromatograph is a focus of the analysis and test technology.
Detecting light hydrocarbon components in the natural gas, and firstly carrying out enrichment pretreatment on the light hydrocarbon in the natural gas. The existing gas washing method, thermal evaporation method, rock sealing extraction, rock low boiling point light hydrocarbon extraction method and adsorption-acid hydrolysis hydrocarbon analysis method are only suitable for crude oil and hydrocarbon source rock samples with higher light hydrocarbon content, while the slow curtain (1990) design pressurizing sampling method is only suitable for analyzing natural gas with higher humidity, and the natural gas steel cylinder needs to be heated to 120 ℃, so that great potential safety hazard exists; the quartz tube enrichment method disclosed by Zhang Hei et al (1994) has limited gas volume of the collected natural gas, and the six-way valve part is easy to generate errors, and light hydrocarbon components cannot be accurately detected. In recent years, studies have been conducted on the analysis of light hydrocarbons in natural gas by using Solid Phase Microextraction (SPME) technology (Li et)
2014) However, butThe method is not mature, and the detection of light hydrocarbon components in natural gas cannot be realized at present. Wangshun jade and the like disclose a natural gas C3-C8A new method for the analysis of hydrocarbon concentrates, which makes C for the direct collection of a concentrated sample of natural gas at an onsite wellhead3-C8In the hydrocarbon concentrator, however, it is necessary to perform a treatment such as elution of an impurity gas such as methane or ethane in the concentrator during the detection.
Disclosure of Invention
In order to realize efficient, simple, convenient, safe and accurate analysis and test of trace light hydrocarbon components in natural gas in a natural gas sample, provide more reliable experimental data for geochemical research, carry out scientific research on geochemical indexes of light hydrocarbon components in natural gas and promote the gas-oil-source comparison work in geological science, the invention establishes a set of device and a method for circularly enriching natural gas with a fixed volume by using a molecular sieve, and can collect the enriched light hydrocarbon components on line and transfer the light hydrocarbon components to gas chromatography for analysis. The device and the method can simply, conveniently, safely, accurately and efficiently enrich trace light hydrocarbon components in the natural gas.
In order to achieve the technical purpose of the invention, the invention provides a method for collecting light hydrocarbon in natural gas in a laboratory, which comprises the following steps:
the natural gas repeatedly flows through a pipeline filled with the molecular sieve in the vacuum circulating system, so that light hydrocarbon in the natural gas is enriched in the molecular sieve;
in a vacuum circulating system, the molecular sieve enriched with light hydrocarbon is heated, and the light hydrocarbon released by the molecular sieve is collected and obtained.
Wherein the light hydrocarbon is C5 hydrocarbon, C6 hydrocarbon, C7 hydrocarbon and C8 hydrocarbon.
Wherein the vacuum circulating system is a vacuum pipeline connected with a molecular sieve in series;
in particular, an air pump and a vacuum pump are arranged on the vacuum pipeline.
The pipeline filled with the molecular sieve can be a U-shaped pipe or other pipelines which can increase the contact area of the natural gas and the molecular sieve and can enable the gas to flow.
In particular, the molecular sieve is
And (3) a molecular sieve.
In particular, in order to make the vacuum pipeline have a good vacuum environment, the vacuum pump is arranged at one end of the vacuum pipeline, and a valve is arranged on the pipeline connecting the vacuum pump and the pipeline.
Wherein, in order to the vacuum environment of the observation pipeline that can be directly perceived, this application sets up the vacuum gauge at the other end of vacuum pipeline for indicate the vacuum environment of pipeline.
The air pump is arranged at one end close to the vacuum gauge, and after the air pump is started after the pipeline forms a circulation loop, the air pressure difference of the air pump enables the airflow in the pipeline to generate directional circulation flow, so that the circulation flow of the natural gas is realized.
The pipeline filled with the molecular sieve is arranged in the middle section of the vacuum pipeline, so that the natural gas slowly flows into the pipeline filled with the molecular sieve, and the flowing out filtered natural gas slowly flows into the natural gas storage device.
In particular, a gas extraction port is provided at one end of the tube containing the molecular sieve for collecting gas released from the molecular sieve.
In particular, valves for controlling the gas flow are arranged at one end of the pipeline filled with the molecular sieve and the other end of the gas extraction port, and are used for controlling the gas flow in the molecular sieve and the gas extraction port.
In order to achieve the technical object of the present invention, another aspect of the present invention provides an online circulation system for collecting natural gas light hydrocarbon in a laboratory, comprising:
a natural gas storage unit;
a light hydrocarbon adsorption unit with a molecular sieve inside;
a light hydrocarbon collection unit;
the circulating power unit is arranged between the adsorption unit and the storage unit; and
and the natural gas storage unit, the circulating power unit, the light hydrocarbon adsorption unit and the light hydrocarbon sampling unit are sequentially connected in series to form a vacuum pipeline of a circulating system.
The vacuum pipeline is provided with an air pump, a vacuum pump and a plurality of valves for controlling air flow.
The natural gas storage unit is any commercially available high-pressure steel cylinder with straight-through valves at two ends.
The light hydrocarbon adsorption unit is a stainless steel pipe with a molecular sieve inside, the pipeline is a U-shaped pipe, and the stainless steel pipe can increase the contact area of natural gas and the molecular sieve and enable gas to flow.
In particular, the molecular sieve used in the light hydrocarbon adsorption unit is
And (3) a molecular sieve.
The invention only utilizes
The molecular sieve can absorb light hydrocarbon in natural gas, and has the advantages of single material, low cost and simple and convenient use.
Wherein, light hydrocarbon adopts the unit to include:
the heating devices are arranged at the periphery of the light hydrocarbon adsorption unit;
and the gas taking port is arranged on the adjacent pipeline of the light hydrocarbon adsorption unit.
The heating device is any commercially available high-temperature furnace which can be arranged on a stainless steel pipe, and can have a temperature control function and an intelligent adjusting function.
The light hydrocarbon adsorbed in the adsorption unit can be resolved by starting the heating device, and the method is simple.
Wherein, get gas port department and use the silica gel pad to seal.
When needs carry out the ration sample to light hydrocarbon, can utilize current ration sampling equipment to insert the rubber pad and extract, also can utilize external derivation equipment, with the quantitative derivation of light hydrocarbon in the circulation system.
In particular, the light hydrocarbon collection unit may be connected to the detection system via existing quantitative sampling equipment.
Wherein, the detecting system is a gas chromatograph or other analytical equipment for analyzing light hydrocarbon.
In order to achieve the technical purpose of the invention, the invention also provides the application of the method for collecting light hydrocarbon in natural gas in the laboratory to the geochemical analysis of the gas.
The light hydrocarbon collected by the method has extremely low impurity content and high content, and can meet the requirements of gas geochemical analysis.
To achieve the technical object of the present invention, the present invention further provides an apparatus for analyzing chemical composition of light hydrocarbon in natural gas, which has the on-line circulation system for collecting light hydrocarbon in natural gas as claimed above.
Advantageous effects
The invention is provided by constructing
Recycle systems for molecular sieves, i.e. obtaining pure C from natural gas with very low light hydrocarbon content5-C8The light hydrocarbon gas is used for geochemical experimental analysis, and has the advantages of simple method, low cost, simple and convenient operation, high acquisition efficiency and stable test result.
Drawings
Fig. 1 is a schematic structural diagram of an on-line circulation collection system for light hydrocarbons in natural gas provided in embodiment 1 of the present invention.
FIG. 2 is a line graph of molecular sieve adsorbent composition versus time in the recycle system provided in test example 1 of the present invention;
FIG. 3 is a line graph showing the relationship between the adsorption amounts of the molecular sieve to methane, ethane, isobutane and isopentane with time in the recycle system according to test example 1 of the present invention;
FIG. 4 is a graph showing the relationship between the release amount of each component and the desorption temperature at an adsorption time of 30min in the circulation system according to test example 2 of the present invention;
fig. 5 is a graph showing changes in the content of gas components desorbed at eight desorption temperatures when the adsorption time is 30min in the circulation system provided in test example 2 of the present invention, wherein 1 is methane; 2. ethane; 3. propane; 4; isobutane; 5. n-butane; 6. isopentane; 7. n-pentane; 8. 2, 2-dimethylbutane; 9. cyclopentane + 2, 3-dimethylbutane; 10. 2-methylpentane; 11. 3-methylpentane; 12. n-hexane; 13. methylcyclopentane.
In fig. 1, a natural gas storage unit, 11, a high-pressure steel cylinder, 12 and a connecting piece; 2. light hydrocarbon adsorption unit, 21, molecular sieve; 3. a light hydrocarbon collecting unit 31, a heating device 32, an air intake 321, a connecting piece 322 and a silica gel pad; 4. a circulating power unit; 5. vacuum pipeline, 51, vacuum gauge, 52, vacuum pump, 53, valve, 54, valve, 55, valve.
Detailed Description
The present invention will be further described with reference to specific examples and test examples. It should be understood that these examples and test examples are only for illustrating the present invention and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers.
The present invention will now be described with reference to specific examples and test examples, which are intended to be illustrative only and should not be construed as limiting the invention. The technical means used in the examples and test examples are conventional means well known to those skilled in the art and the reagents and products used are commercially available, unless otherwise specified. Various procedures and methods not described in detail are conventional methods well known in the art, and the sources, trade names, and components of the reagents used are indicated at the time of first appearance, and the same reagents used thereafter are the same as those indicated at the first appearance, unless otherwise specified.
As shown in fig. 1, the on-line circulation collection system for light hydrocarbon in natural gas provided by the invention comprises: a natural gas storage unit 1; a light hydrocarbon adsorption unit 2; a light hydrocarbon collecting unit 3; a circulating power unit 4; a vacuum line 5 with a valve 51 and a vacuum pump 52.
Further, the natural gas storage unit 1 includes a high pressure steel cylinder 11 storing natural gas and a connection 12 connecting the high pressure steel cylinder 11 to a vacuum line.
Specifically, the high-pressure steel cylinder 11 for storing natural gas is a high-pressure steel cylinder conventionally used in the art, and has a straight-through valve 13 at both ends thereof, such as an LPG stainless steel sampling steel cylinder sold by electromechanical technologies ltd of Jiangsu Wheatstone.
Specifically, the connecting member 12 is a commercially available stainless steel sealing joint capable of connection.
Further, the light hydrocarbon adsorption unit 2 is a U-shaped pipe, and a molecular sieve 21 is installed inside the U-shaped pipe.
In particular, the molecular sieve is commercially available
And (3) a molecular sieve.
Further, the light hydrocarbon collecting unit 3 comprises heating devices 31 arranged around the light hydrocarbon adsorption unit; and an air intake 32 disposed on the adjacent pipeline of the light hydrocarbon adsorption unit.
In particular, the gas extraction port 32 is connected to the circulation system via a connection 321.
Specifically, the air intake port 32 may be closed by a silicone pad 322.
Specifically, the heating device 31 may be any commercially available device capable of heating the U-shaped pipe, for example, a high temperature furnace, or any commercially available high temperature furnace capable of temperature control, and the connector 321 may be any commercially available stainless steel sealing joint capable of connection.
Further, the circulating power unit 4 is a commercially available micro air pump. The invention utilizes the pressure difference generated at the two ends of the micro air pump to make the airflow in the system generate directional circulating flow.
Further, the vacuum pipeline 5 connects the natural gas storage unit 1, the circulating power unit 4, the light hydrocarbon adsorption unit 2 and the light hydrocarbon sampling unit 3 in series in sequence to form a circulating system, and the circulating power unit 4 is utilized to enable the natural gas to flow in the natural gas storage unit 1 and the light hydrocarbon adsorption unit 2 in a circulating mode along one direction.
Specifically, the vacuum pipeline 5 is provided with a vacuum gauge 51, a vacuum pump 52, a valve 53 sequentially arranged between the circulating power unit 4 and the light hydrocarbon adsorption unit 2, and a valve 54 and a valve 55 on the pipeline between the gas intake port 32 and the natural gas storage unit 1.
Specifically, the vacuum gauge 51 is used to indicate the vacuum degree in the circulation system, the vacuum pump 52 is used to establish the vacuum environment in the circulation system, and also to discharge the impurity gas, the valve 55 is used to control the opening and closing of the vacuum pump, and the valve 53 and the valve 54 are used to open and close the gas flow at both ends of the light hydrocarbon adsorption unit 2.
Specifically, the vacuum lines used in the present invention are commercially available stainless steel tubes, and in one embodiment of the present invention, the vacuum lines are made of 1/4-inch stainless steel tubes from Swagelok.
The invention has simple structure and low cost, and especially, the adsorption carrier in the light hydrocarbon adsorption unit 2 only needs to be
The molecular sieve has the advantages of single component, convenient replacement and low cost.
Example 2 on-line circulation collection method of light hydrocarbon in natural gas
The method for collecting light hydrocarbon in natural gas by using the system provided by the embodiment 1 comprises the following steps:
1. mounting connection for natural gas storage device
Firstly, the high-pressure steel cylinder 11 for collecting natural gas is connected into the circulating adsorption system by using the connecting piece 12 according to the structural connection relationship provided in the embodiment 1, and the through valves 13 at two ends of the high-pressure steel cylinder are in a closed state.
2. Test for gas tightness
And (3) closing the gas taking port, carrying out leak detection on the circulating adsorption system connected with the high-pressure steel cylinder 11, checking whether the gas tightness of each part of the system is good, adopting a conventional method in the field for the leak detection method, observing whether the vacuum gauge changes by closing the valve 55, judging that the gas tightness of the circulating system is good if the reading of the vacuum gauge does not change greatly, and indicating that the gas tightness of the system is poor if the reading of the vacuum gauge is increased.
3. Building a vacuum circulation System
The vacuum pump 52 is turned on and the line valve 53 and valves 54, 55 are opened, as the vacuum gauge is shown
At this point, valve 55 is closed, and the system is purged of air. Then the straight-through valves 13 at the two ends of the high-pressure steel cylinder are slowly opened, and the micro air pump 4 is simultaneously opened, so that the natural gas in the system generates directional circulating flow due to the pressure difference generated at the two ends of the air pump.
4. Adsorption of light hydrocarbons in natural gas
The natural gas flows out from one end of the high-pressure steel cylinder 11 and flows through the U-shaped pipe 2 along the vacuum pipeline 5 due to the action of the micro air pump 4
A molecular sieve is used for the molecular sieve,
the molecular sieve absorbs light hydrocarbon in the natural gas, the residual natural gas returns to the high-pressure steel cylinder 11, and when the natural gas continuously flows out of the high-pressure steel cylinder, passes through the U-shaped pipe 2 and then continuously flows into the high-pressure steel cylinder 11, the natural gas and the natural gas are enabled to be mixed
The molecular sieve is contacted repeatedly, and light hydrocarbon in the natural gas is continuously in
And (4) enriching in the molecular sieve.
5. Extraction of light hydrocarbons from natural gas
After the light hydrocarbon adsorption is completed, the valve 55 is opened, and the vacuum pump 52 is started to discharge the impurity gas. Then, the valve 53 and the valve 54 are closed, the heating device 31 is opened to heat the U-shaped tube, so that the light hydrocarbon components adsorbed by the molecular sieve are desorbed, after a period of heating, the light hydrocarbon gas is taken from the gas taking port by using the existing quantitative sampling equipment, for example, an external device with a fixed volume of saturated saline water is connected with the gas taking port, and the light hydrocarbon is quantitatively taken. Because the light hydrocarbon adopted by the method has high purity, the light hydrocarbon collected from the gas taking port can be directly used for gas chromatography detection, thereby carrying out gas geochemical analysis.
Application examples
A high-pressure steel cylinder having a capacity of 1L was connected to the adsorption system of example 1, and 3g of the solution was charged in a U-shaped tube in the adsorption system
Molecular sieves are subjected to daughter-in-law and collection of light hydrocarbons using the method provided in example 2.
Specifically, the adsorption time is 30-60min, the impurity gas discharge time is 30s, the heating temperature is less than 300 ℃, and the heating time is 2 min.
Detecting that the impurity gas is methane, ethane, propane, isobutane and normal butane; the gas collected from the gas extraction port is isopentane, n-pentane, 2-dimethylbutane, cyclopentane +2, 3-dimethylbutane, 2-methylpentane, 3-methylpentane, n-hexane, methylcyclopentane.
Therefore, the on-line circulation collection system for light hydrocarbon in natural gas provided by the invention can efficiently and accurately collect light hydrocarbon gas in natural gas with extremely low content.
The following are some of the tests performed during the development of the present invention, in particular:
test example 1 adsorption Effect test of Components at different adsorption times
In order to study in the circulatory system
The adsorption behavior of the molecular sieve on the light hydrocarbon components of the natural gas selects different adsorption time for testing, which respectively comprises the following steps: 5min, 10min, 30min, 60min, 150min, 300min, the desorption temperature of the sample is from 15 minThe temperature is 0-500 deg.C, and is divided into 150 deg.C, 200 deg.C, 250 deg.C, 300 deg.C, 350 deg.C, 400 deg.C, 450 deg.C, and 500 deg.C. The sample volume during chromatographic detection is all 0.5mL, so that in order to avoid various accidental errors caused by single sample introduction, the samples collected in each adsorption time period are tested repeatedly for multiple times (n is more than or equal to 5), and an average value is taken. After the molecular sieve passes through different adsorption time, the total amount of adsorbed light hydrocarbon is the sum of the gas amount analyzed at each temperature point. The experimental data are shown in table 1, fig. 2 and fig. 3.
TABLE 1 adsorption content of various components of molecular sieves at different adsorption times
Note: the amounts of the components are expressed as the area of the chromatographic peak (mV. s), and the data in the table is the sum of the amounts of gases desorbed from each component at six temperature points, 150 ℃, 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃ and 500 ℃.
From the results in table 1 and fig. 1, it can be seen that the adsorption capacity of the molecular sieve to propane, n-butane, n-pentane, 2-dimethylbutane, cyclopentane +2, 3-dimethylbutane, 2-methylpentane, 3-methylpentane, n-hexane, methylcyclopentane increased with time before 60min, reached a maximum between 30 and 60min, and then decreased with increasing adsorption time. Indicating that the molecular sieve has a unimodal distribution of the adsorption of these components over time. Although the adsorption amount of the molecular sieve to methane, ethane, isobutane and isopentane fluctuates greatly with time as shown in fig. 2, the trend of the total adsorption amount of the molecular sieve is still maximum between 30min and 60min within the same adsorption time. After 60min, the adsorption capacity begins to decrease, and it can be seen that the molecular sieve starts to diffuse after adsorption reaches equilibrium.
It can also be seen from FIG. 2 that the adsorption of methane is minimal at 30min and that the adsorption of the other components is substantially maximal at 30min. Thus setting the adsorption time at 30min effectively filters out the main Component (CH) in the natural gas4) Thereby achieving the purpose of light hydrocarbon concentration.
Through the analysis, the optimal adsorption time of 30min can be obtained.
Test example 2 contents of respective components released at different desorption temperatures
According to the test analysis results of test example 1, the applicant desorbed hydrocarbons from the molecular sieve in the circulation system at eight temperature points of 150 ℃, 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃ and 500 ℃ respectively, with the temperature error controlled within + -10 ℃. The composition data thus obtained are shown in Table 2 and FIG. 4.
TABLE 2 content of components released at different desorption temperatures
Note: the data in the table are the peak areas (mV. s) of the chromatogram for each component
It can be seen from table 2 and fig. 4 that the total amount of gas released is maximum when the desorption temperature is 300 deg.c. The amount of gas released before 300 ℃ gradually increases; after the desorption temperature exceeds 300 ℃, the amount of desorbed gas is reduced sharply. Indicating that most of light hydrocarbon components absorbed by the molecular sieve can be released at 300 ℃.
According to the change curve of the release amount of each component in the molecular sieve with the desorption temperature shown in fig. 5, the desorption amounts of components such as methane, ethane, isopentane, 2-dimethylbutane and the like are reduced with the increase of the desorption temperature, and isobutane is basically and completely released before 300 ℃. Indicating that these components can be released from the molecular sieve at a lower desorption temperature. The desorption amount of components such as propane, n-butane, n-pentane and n-hexane reaches the maximum at 300 ℃. The methane content in the adsorbed gas is obviously reduced, which shows that the 5A molecular sieve also has the functions of filtering methane and concentrating light hydrocarbon.
It can also be seen from fig. 5 that methane and ethane have the lowest content in the desorbed gas at 300 ℃ and 350 ℃, the content of the components after isopentane in the desorbed gas gradually increases with the increase of temperature, and the effect that the content of the components with higher carbon number increases with the increase of temperature is more obvious because the thermodynamic property of the hydrocarbon molecule with higher carbon number determines that the hydrocarbon molecule with higher carbon number needs higher desorption temperature to be separated from the desorbed gasAnd (3) a molecular sieve. Sample after 5A molecular sieve adsorption and C compared to the original sample composition5 +The component concentration is obviously increased.
Test example 3
Reproducibility test of molecular sieve enrichment effect
The invention also tests in the test process
Reproducibility of the molecular sieve enrichment effect (the repetition number n is 7), and the conditions are selected as follows: the adsorption time is 30min, the desorption temperature is 300 ℃, the chromatographic detection conditions are unchanged, and the data are shown in table 3. The standard deviation of all light hydrocarbon components was less than 0.4.
TABLE 35A molecular Sieve enrichment repeat test
Column: the data in the table are the percentage concentration (%)
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (9)
1. A method for collecting light hydrocarbons in natural gas in a laboratory is characterized by comprising the following steps:
the natural gas repeatedly flows through a pipeline filled with the molecular sieve in the vacuum circulating system, so that light hydrocarbon in the natural gas is enriched in the molecular sieve;
heating the molecular sieve enriched with light hydrocarbon in a vacuum circulating system, and collecting the light hydrocarbon released by the molecular sieve;
wherein the light hydrocarbon is C5Hydrocarbons, C6Hydrocarbons, C7Hydrocarbons, C8A hydrocarbon.
2. The method for laboratory collection of light hydrocarbons from natural gas according to claim 1, wherein said vacuum circulation system is a vacuum line in series with molecular sieves;
wherein, the vacuum pipeline is provided with an air pump and a vacuum pump.
3. The method for laboratory collection of light hydrocarbons from natural gas according to either of claims 1 and 2, wherein the molecular sieve is selected from the group consisting of
And (3) a molecular sieve.
4. An on-line circulation system for collecting natural gas light hydrocarbons, comprising:
a natural gas storage unit;
a light hydrocarbon adsorption unit with a molecular sieve inside;
a light hydrocarbon collection unit;
the circulating power unit is arranged between the adsorption unit and the storage unit; and
and the natural gas storage unit, the circulating power unit, the light hydrocarbon adsorption unit and the light hydrocarbon sampling unit are sequentially connected in series to form a vacuum pipeline of a circulating system.
5. The on-line circulation system for collecting light hydrocarbons in natural gas as claimed in claim 4, wherein the vacuum pipeline is provided with an air pump and a vacuum pump, and a valve for controlling air flow.
6. The on-line circulation system for collecting light hydrocarbons from natural gas as claimed in claim 4, wherein said light hydrocarbon extraction unit comprises:
the heating devices are arranged at the periphery of the light hydrocarbon adsorption unit;
and the gas taking port is arranged on the adjacent pipeline of the light hydrocarbon adsorption unit.
7. The on-line circulation system for collecting light hydrocarbons in natural gas as claimed in claim 4, wherein the light hydrocarbon collection unit is connected to the detection system via existing quantitative sampling equipment.
8. Use of the laboratory method for the collection of light hydrocarbons in natural gas according to any one of claims 1 to 4 for the geochemical analysis of gases.
9. An apparatus for analyzing chemical composition of light hydrocarbon in natural gas, which comprises the on-line circulation system for collecting light hydrocarbon in natural gas as claimed in any one of claims 4 to 6.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010606583.8A CN111624273A (en) | 2020-06-29 | 2020-06-29 | Method for collecting light hydrocarbons in natural gas in laboratory, online circulation system and application |
| NL2028533A NL2028533B1 (en) | 2020-06-29 | 2021-06-24 | Method and online circulation system for collecting light hydrocarbon in natural gas |
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| CN202010606583.8A CN111624273A (en) | 2020-06-29 | 2020-06-29 | Method for collecting light hydrocarbons in natural gas in laboratory, online circulation system and application |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114088832A (en) * | 2021-11-12 | 2022-02-25 | 中国科学院西北生态环境资源研究院 | Deep-ultra-deep hydrocarbon source rock normal paraffin light component and isotope analysis system and method |
| CN117531333A (en) * | 2024-01-08 | 2024-02-09 | 西安瑞恒测控设备有限公司 | Filtering system of gas chromatograph in krypton-xenon detection |
-
2020
- 2020-06-29 CN CN202010606583.8A patent/CN111624273A/en active Pending
-
2021
- 2021-06-24 NL NL2028533A patent/NL2028533B1/en active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114088832A (en) * | 2021-11-12 | 2022-02-25 | 中国科学院西北生态环境资源研究院 | Deep-ultra-deep hydrocarbon source rock normal paraffin light component and isotope analysis system and method |
| CN117531333A (en) * | 2024-01-08 | 2024-02-09 | 西安瑞恒测控设备有限公司 | Filtering system of gas chromatograph in krypton-xenon detection |
| CN117531333B (en) * | 2024-01-08 | 2024-04-02 | 西安瑞恒测控设备有限公司 | Filtering system of gas chromatograph in krypton-xenon detection |
Also Published As
| Publication number | Publication date |
|---|---|
| NL2028533B1 (en) | 2023-03-24 |
| NL2028533A (en) | 2022-02-17 |
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