Micro-chromatography continuous analysis system for LNG (Liquefied Natural Gas)

Abstract

The invention provides an LNG micro-chromatography continuous analysis system, the gas inlet end of a gasification assembly is connected to a gas source through an inlet pipeline, a nitrogen generation assembly is arranged on the inlet pipeline, the inlet end of a micro-chromatography analysis assembly or the outlet end of a pressure balance assembly is further connected in series with a steel cylinder assembly, the nitrogen generation assembly is used for periodically purging and cleaning the analysis system, and the nitrogen generation assembly is used for generating nitrogen. And the steel cylinder assembly is used for circularly sampling or externally connecting the micro chromatographic analysis assembly with a sample for analysis. The analysis system has a regular automatic nitrogen purging function, the micro chromatographic analysis assembly can continuously analyze LNG, meanwhile, the analysis system further has a liquefied natural gas gasification pressure stabilization and constant flow function and a low-pressure metering function that liquefied natural gas enters the micro analysis module after gasification, and an overpressure safe discharge function is designed on an analysis main path; stability and safety of continuous analysis of the system can be improved, the system can be directly connected to an analysis component through the inlet pipeline, manual sample feeding is reduced, and detection frequency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of liquefied natural gas analysis, and in particular relates to a continuous analysis system for LNG microchromatography. Background Art

[0002] As the development of LNG technology and industry enters a mature stage, LNG quality supervision has become the most advantageous way for LNG peers to compete. At present, LNG chromatographs have begun to be popularized in various domestic related industries, but the use environment is not comprehensive. The existing LNG online chromatographic analysis can be used for the content analysis of various components of natural gas, and the chromatographic workstation can automatically calculate the LNG high calorific value, low calorific value, Wobbe number, density, combustion potential and other characteristic indexes. It has full computer operation, color touch screen control, human-computer dialogue mode, easy operation, and can stably monitor the quality of LNG online. However, there is no supporting online continuous analysis system, and it is necessary to use manual sample delivery to analyze samples one by one. The analysis efficiency is low and the labor intensity is high. Summary of the invention

[0003] In view of this, the present invention aims to propose a continuous analysis system for LNG microchromatography to solve the problem that the prior art LNG online chromatographic analysis requires manual sample delivery for analysis one by one, which has low analysis efficiency and high labor intensity.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] A system for continuous analysis of LNG micro-chromatography comprises a gasification component, a buffer component, a pressure balance component, a micro-chromatography analysis component and a nitrogen generating component arranged in a protective cabinet, wherein the gas outlet end of the gasification component is connected to the micro-chromatography analysis component via the buffer component and the pressure balance component in sequence, the gas inlet end of the gasification component is connected to a gas source via an inlet pipe, and a nitrogen generating component is arranged on the inlet pipe, a cylinder component is further connected in series to the inlet end of the micro-chromatography analysis component or the outlet end of the pressure balance component, the nitrogen generating group is used for periodically purging and cleaning the analysis system, and the cylinder component is used for cyclic sampling or external sample analysis of the micro-chromatography analysis component.

[0006] Furthermore, a polyurethane cold insulation layer is arranged on the periphery of the inlet pipe; and a combustible gas leakage alarm is arranged in the protective cabinet.

[0007] Furthermore, the gasification component includes a gasification pipeline, and a heating module is arranged around the gasification pipeline, a temperature sensor a is arranged at the front end of the gasification pipeline, a temperature sensor c and a pressure sensor are arranged at the rear end of the gasification pipeline, and a temperature sensor b is arranged inside the gasification pipeline.

[0008] Furthermore, the buffer assembly includes a gasification buffer tank, and the inlet end of the gasification buffer tank is connected to the outlet end of the gasification assembly, and a first one-way valve is arranged between the inlet end of the gasification buffer tank and the outlet end of the gasification assembly, and the passage connecting the inlet end of the gasification buffer tank to the outlet end of the gasification assembly is opened and closed by a ball valve a.

[0009] Furthermore, the pressure balancing assembly includes a thermal compensation pressure regulating assembly, a first pipeline is installed at the outlet end of the gasification buffer tank, and a thermal compensation pressure regulating assembly is arranged on the first pipeline, and a ball valve b, a needle valve and a pressure gauge are also arranged on the first pipeline, the ball valve b is located at the front end of the thermal compensation pressure regulating assembly, and the needle valve and the pressure gauge are located at the rear end of the thermal compensation pressure regulating assembly.

[0010] Furthermore, the outlet end of the first pipeline is connected to the inlet end of the micro-chromatographic analysis component through the second pipeline, and a low-pressure regulating valve, a ball valve d and a flow meter are respectively arranged on the second pipeline, and the outlet end of the micro-chromatographic analysis component is connected to the recovery pipeline.

[0011] Furthermore, the cylinder assembly is connected to the outlet end of the first pipeline or the inlet end of the second pipeline through a third pipeline.

[0012] Furthermore, the micro-chromatographic analysis component is also connected in series to the gas supply component, and the gas medium of the gas supply component can enter the micro-chromatographic analysis component through the pressure regulating component.

[0013] Furthermore, the nitrogen generating assembly includes an air buffer tank, and a positive pressure pump is installed at the air inlet end of the air buffer tank, the air outlet end of the air buffer tank is connected to the gas molecular membrane separator through a fourth pipeline, and a filter and an oil-water drying separator are sequentially arranged on the fourth pipeline, the nitrogen outlet end of the gas molecular membrane separator is connected to the nitrogen temporary storage tank, the impurity gas outlet end of the gas molecular membrane separator is facing the air, the nitrogen temporary storage tank is connected to the nitrogen bottle through a fifth pipeline, and a delivery pump and a pressure regulating valve are arranged on the fifth pipeline, and the air outlet end of the nitrogen bottle is connected to the inlet pipeline.

[0014] Furthermore, the thermal compensation voltage regulating component includes a base, which is sleeved on the first pipe, and a first groove and a second groove are provided at the bottom of the base. A micro heating component is arranged in the first groove, and a temperature sensor d is arranged in the second groove.

[0015] Compared with the prior art, the LNG microchromatography continuous analysis system described in the present invention has the following beneficial effects: it has a periodic automatic nitrogen purge function, the micro-chromatography analysis component can continuously analyze LNG, and it also has a liquefied natural gas gasification pressure stabilization and constant flow function, and the liquefied natural gas enters the micro-analysis module after gasification. Low-pressure metering and component analysis function, and an overpressure safety discharge function is designed in the main analysis path, which can improve the stability and safety of the system's continuous analysis, and can directly reach the analysis component through the inlet pipe, reducing manual sample delivery and increasing the detection frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 This is a schematic diagram of the operating principle of a LNG microchromatography continuous analysis system according to an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the operating principle of the nitrogen generating assembly according to an embodiment of the present invention;

[0019] Figure 3 It is a schematic structural diagram of the base described in an embodiment of the present invention.

[0020] Description of reference numerals:

[0021] 1-protection cabinet; 101-combustible gas leakage alarm; 2-gasification component; 21-gasification pipeline; 22-heating module; 23-temperature sensor a; 24-temperature sensor c; 25-pressure sensor; 26-temperature sensor b; 3-buffer component; 31-gasification buffer tank; 32-first one-way valve; 33-ball valve a; 34-pressure reducing valve; 4-pressure balance component; 41-first pipeline; 42-thermal compensation pressure regulating component; 421-base; 422-first groove; 423-second groove; 43-ball valve b; 44-needle valve; 45-pressure gauge; 46-second pipeline; 47-low-pressure regulating valve; 48-ball valve d; 49-flow meter; 5-micro-chromatographic analysis component; 6-nitrogen generating component; 61-air buffer tank; 62-positive pressure pump; 63-fourth pipeline; 64-gas molecular membrane separator; 65-filter; 66-oil-water drying separator; 67-nitrogen temporary storage tank; 68-fifth pipeline; 69-nitrogen cylinder; 610-delivery pump; 611-pressure regulating valve; 7-inlet pipeline; 71-polyurethane cold insulation layer; 8-gas source; 9-steel cylinder assembly; 91-third pipeline; 10-recovery pipeline; 11-gas supply assembly; 12-gas supply pressure regulating assembly. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0025] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0026] like Figure 1-Figure 3As shown, a system for continuous analysis of LNG micro-chromatography includes a gasification component 2, a buffer component 3, a pressure balance component 4, a micro-chromatography analysis component 5 and a nitrogen generating component 6 arranged in a protective cabinet 1, and the gas outlet end of the gasification component 2 is connected to the micro-chromatography analysis component 5 through the buffer component 3 and the pressure balance component 4 in turn, the gas inlet end of the gasification component 2 is connected to the gas source 8 through the inlet pipe 7, and the nitrogen generating component 6 is arranged on the inlet pipe 7, and the inlet end of the micro-chromatography analysis component 5 or the outlet end of the pressure balance component 4 is also connected in series with a cylinder component 9, and the nitrogen generating component is used for The analysis system is purged and cleaned regularly, and the cylinder component 9 is used for cyclic sampling or external sample analysis of the micro-chromatographic analysis component 5. The analysis system has a regular automatic nitrogen purging function. The micro-chromatographic analysis component 5 can continuously analyze LNG. It also has a liquefied natural gas gasification pressure stabilization and constant flow function. The liquefied natural gas enters the micro-analysis module after gasification and has a low-pressure metering function. The overpressure safety discharge function is designed in the main analysis path, which can improve the stability and safety of the system's continuous analysis. It can be directly connected to the analysis component through the inlet pipe 7, reducing manual sample delivery and increasing the detection frequency.

[0027] A polyurethane cold insulation layer 71 is arranged on the periphery of the inlet pipe 7, and the coating thickness is not less than 50 mm. A combustible gas leakage alarm 101 is arranged in the protective cabinet 1. The combustible gas leakage alarm 101 is a prior art. All valves, joints, and pipeline components except the pipeline treated with polyurethane cold insulation coating at the rear end of the inlet pipe 7 are installed in the system protective cabinet 1, and the valves, joints, and pipelines can be used normally under LNG-176°C conditions. The gasification component 2 includes a gasification pipeline 21, and a heating module 22 is arranged on the periphery of the gasification pipeline 21, a temperature sensor a23 is arranged at the front end of the gasification pipeline 21, and a temperature sensor a24 is arranged at the rear end of the gasification pipeline 21. Sensor c24 and pressure sensor 25, temperature sensor b26 is arranged in the gasification pipeline 21, the protective cabinet 1 is made of 316L stainless steel as a whole, and has static elimination function, and a combustible gas leakage alarm 101 is designed to perform real-time leakage alarm monitoring on the system protective cabinet 1, and the protection level of the system protective cabinet 1 is not less than IP55, which can meet the requirements of waterproof and dustproof. All pipelines in contact with LNG samples in the system are made of 316L stainless steel, and all pipelines, joints, and valve components are required to be treated with sulfur passivation coating to prevent some components in LNG from being adsorbed during continuous analysis and affecting the accuracy of analysis.

[0028] The buffer component 3 includes a gasification buffer tank 31, which has a volume of 500ml or 1L and can effectively and stably buffer the instantaneous expansion pressure after LNG gasification. Its main body is made of 316L stainless steel, and the part in contact with LNG is sulfur passivated. The inlet end of the gasification buffer tank 31 is connected to the outlet end of the gasification component 2, and a first one-way valve 32 is arranged between the inlet end of the gasification buffer tank 31 and the outlet end of the gasification component 2. The passage connecting the inlet end of the gasification buffer tank 31 to the outlet end of the gasification component 2 is opened and closed by a ball valve a33. A pressure reducing valve 34 is arranged on the gasification buffer tank 31, and the pressure reducing valve 34 is connected to the recovery pipeline 10, and the pressure reducing valve 34 is an installation valve. The safety valve is connected to the system exhaust pipeline. The safety valve can be set to a pressure of 3 to 10Bar according to the system analysis sampling requirements. If the actual instantaneous pressure of the main line is greater than the set pressure, the system can be automatically discharged at overpressure.

[0029] The gasification component 2 has the function of automatic temperature and pressure detection and control. The temperature sensor a23 is designed at the front end of the gasification component 2 to monitor the LNG temperature before gasification; the temperature sensor b26 is designed during the vaporization process of the gasification component 2 to monitor the temperature changes during the gasification process in real time, and is equipped with a temperature control module to accurately control the real-time temperature of the gasification device; the temperature sensor c24 and pressure sensor 25 are designed at the rear end of the gasification component 2 to monitor the temperature and pressure values ​​of the LNG after gasification in real time. In this embodiment, the upper limit of the electric heating of the heating module 22 can reach up to 300°C, and the heating range is 0~80°C after temperature control, which can effectively monitor the operating status and temperature monitoring of the vaporization device. The detection range of the temperature sensor b26 is -200~100°C, and the detection range of the pressure sensor 25 is 0~3.0Mpa.

[0030] The pressure balancing component 4 includes a thermal compensation pressure regulating component 42, which performs secondary temperature compensation on the vaporized LNG to prevent secondary condensation of the LNG and affect the analysis results; the heating temperature control range of the thermal compensation pressure regulating component 42 is 0-50°C, the detection range of the temperature sensor is 0-100°C, the outlet pressure setting range of the thermal compensation pressure regulating component 42 is 0-20Bar, the outlet end of the vaporization buffer tank 31 is installed with a first pipeline 41, and the thermal compensation pressure regulating component 42 is arranged on the first pipeline 41, and the first pipeline 41 is also provided with a ball valve b43, a needle valve 44 and a pressure gauge 45, the ball valve b43 is located at the front end of the thermal compensation pressure regulating component 42, the needle valve 44 and the pressure gauge 45 are located at the rear end of the thermal compensation pressure regulating component 42, and the outlet end of the first pipeline 41 is connected to the first pipeline 41 through the first pipeline 41. The second pipeline 46 is connected to the inlet end of the micro-chromatographic analysis component 5, and a low-pressure pressure regulating valve 47, a ball valve d48 and a flow meter 49 are respectively arranged on the second pipeline 46. The outlet end of the micro-chromatographic analysis component 5 is connected to the recovery pipeline 10. The low-pressure pressure regulating valve 47 is mainly configured to meet the analysis pressure requirement of the micro-chromatographic component. The reduced pressure outlet pressure is consistent with the analysis pressure requirement of the micro-chromatographic component, and the error does not exceed ±0.1Bar. The outlet pressure adjustment range of the low-pressure pressure regulating valve 47 is 0~5Bar, and the accuracy is ±0.1Bar. In this embodiment, the outlet pressure of the low-pressure pressure regulating valve 47 is set to 1.0Bar. The flow meter 49 adopts a float flow meter 49, and the flow adjustment range is 0~5L / min, and the accuracy is ±0.1L / min. In this embodiment, the flow is set to 1L / min.

[0031] The low-temperature pipeline at the front end of the inlet pipe 7 exposed to the environment is designed with a polyurethane insulation layer. The system LNG inlet pipe is introduced into the system gasification device through cryogenic valves a and b. After gasification, LNG enters the buffer tank through ball valve a33 for pressure stabilization. Through ball valve b43 and thermal compensation pressure regulating assembly 42, needle valve 44, low-pressure pressure regulating valve 47, and flow meter 49, LNG finally enters the micro-chromatography assembly for continuous analysis; the front end of the micro-chromatography assembly is equipped with a low-pressure pressure regulating valve 47 and a flow meter 49 to precisely control the analysis pressure, and the micro-chromatography assembly has 3 analysis module assemblies, which can perform more stable analysis of LNG. The external explosion-proof shell is designed to enable the micro-chromatography to be used stably in harsh environments.

[0032] The thermal compensation pressure regulating component 42 includes a base 421, which is sleeved on the first pipe 41. A first groove 422 and a second groove 423 are provided at the bottom of the base 421. A micro heating component is arranged in the first groove 422, and a temperature sensor d is arranged in the second groove 423. In this embodiment, the thermal compensation pressure regulating component 42 is mainly designed with an installation structure of a micro electric heating plate, which is located at the center of the base 421 and can evenly heat the first pipe 41 as a whole; by evenly heating the medium in the first pipe 41, it is avoided that the gas introduced into the rear end by the first pipe 41 may be reduced due to the influence of the ambient temperature. In order to ensure the stability of the temperature compensation of the rear-end chromatographic module data analysis, a temperature control function is also designed on the base 421, and a second groove 423 with an installation space for a temperature sensor is provided, which can automatically control the temperature change of the thermal compensation component. The temperature control range is 0 to 50°C. When the temperature is ≥50°C, the micro electric heating plate automatically stops heating.

[0033] The safety valve connected to the gasification buffer tank 31 is connected to the recovery pipe 10; the cylinder assembly 9 is connected to the outlet end of the first pipe 41 or the inlet end of the second pipe 46 through the third pipe 91, and the one-way valve at the rear end of the exhaust port of the micro-chromatography assembly is connected to the system recovery pipe 10 through the emptying pipeline. The cylinder in the cylinder assembly 9 can be used for sampling and can also be used for sample analysis. The rear end of the cylinder assembly 9 is connected to the recovery pipe 10 through the second one-way valve, which can be used for circulating discharge when the system takes samples through the cylinder assembly 9, and prevent the gas in the recovery pipe 10 from flowing back; the circulation analysis outlet of the micro-chromatography assembly is connected to the recovery pipe 10 through the third one-way valve, which can ensure that the gas in the recovery pipe 10 will not flow back to the micro-chromatography assembly to avoid damage to the assembly, thereby ensuring the safe operation of the assembly.

[0034] The micro-chromatographic analysis component 5 itself is designed with an explosion-proof grade shell of not less than EX db IIC T6Gb in the prior art. The micro-chromatographic analysis component 5 is equipped with three micro-chromatographic analysis modules, GC1, GC2, and GC3, which can effectively meet the analysis requirements of the GB / T38753-2020 "Liquefied Natural Gas" standard for components such as C1~C6+, oxygen (O2), and nitrogen (N2) except total sulfur. The micro-chromatographic analysis component 5 is also connected in series to the gas supply component 11. The gas medium of the gas supply component 11 can enter the micro-chromatographic analysis component 5 through the pressure regulating component 12, and can effectively provide the standard gas and carrier gas pressure of the corresponding pressure according to the requirements of the micro-chromatographic analysis to ensure the stability of the micro-chromatographic analysis. In addition to the system LNG, the gas supply component 11 mainly needs carrier gas and standard gas for analysis. The carrier gas used in the present invention is helium, and the standard gas is a standard LNG gas that is almost similar to the LNG configuration; the gas supply component 11 adjusts the pressure to the required pressure of the chromatographic analysis gas supply through the gas supply pressure regulating component 12 to ensure the analysis stability of the micro-chromatographic component.

[0035] The nitrogen generating assembly 6 comprises an air buffer tank 61, and a positive pressure pump 62 is installed at the air inlet end of the air buffer tank 61, and the air outlet end of the air buffer tank 61 is connected to the gas molecular membrane separator 64 through a fourth pipeline 63, and a filter 65 and an oil-water drying separator 66 are sequentially arranged on the fourth pipeline 63, and the nitrogen outlet end of the gas molecular membrane separator 64 is connected to the nitrogen temporary storage tank 67, and the impurity outlet end of the gas molecular membrane separator 64 is facing the air, and the nitrogen temporary storage tank 67 is connected to the nitrogen bottle 69 through a fifth pipeline 68, and a delivery pump 610 and a pressure regulating valve 611 are arranged on the fifth pipeline 68, and the air outlet end of the nitrogen bottle 69 is connected to the inlet pipeline 7, and the function of the positive pressure pump 62 is to supply air to the nitrogen bottle 69. The compressed air is transmitted and temporarily stored in an air buffer tank 61 with a volume of 1L; the filter 65 can filter the front-end compressed air once to remove particulate matter in the air with a maximum accuracy of 0.22um; the oil-water dry separator 66 can remove moisture and oil gas from the filtered air once, further improving the cleanliness and dryness of the air; the gas molecular membrane separator 64 can separate the gas types of the clean air, and filter out the nitrogen through membrane fiber pressure deposition filtration to introduce it into a nitrogen temporary storage tank 67 with a volume of 1L, and further transport the nitrogen to the nitrogen bottle 69 by controlling the electronic switch valve and the delivery pump 610. The capacity of the nitrogen bottle 69 in this embodiment is 8L.

[0036] In this embodiment, the working pressure of the positive pressure pump 62 is 0-30Bar, it has an automatic heat dissipation function, and the power is 1Kw. The main body of the air buffer tank 61 is made of 316L stainless steel, and the design pressure can reach 200Bar. The filter 65 adopts a membrane filter 65, which can filter solid particles of 0.22um at the minimum, and can effectively purify the compressed air. The maximum working pressure of the oil-water separation dryer is 3.0Mpa (30Bar), the filtration level is 0.1um, and it has an adsorption drying function, which can effectively separate the oil and water in the air and adsorb , and further purify the air. The gas molecular membrane separator 64 can quickly penetrate the sample gas in the air, thereby separating impurity gases such as oxygen through the membrane fiber, thereby obtaining nitrogen with a purity of not less than 99%. The main body of the nitrogen temporary storage tank 67 is made of 316L stainless steel, with a design pressure of 200bar. In conjunction with the electronic switch valve, the front-end nitrogen can be temporarily stored, and then delivered to the nitrogen bottle 69 through the delivery pump 610. The working pressure of the delivery pump 610 is 0-50Bar, and the power is 2Kw, which can increase the pressure of the nitrogen bottle 69 to 50Bar at most.

[0037] A continuous analysis system for LNG microchromatography has the following functions:

[0038] Cleaning system: Start the nitrogen generating assembly 6 to collect nitrogen. When the nitrogen pressure in the nitrogen bottle 69 reaches about 30 Bar, open all valves except cryogenic valve a, cryogenic valve b, and ball valve c, and purge the system for at least 15 minutes. This process only needs to be performed periodically.

[0039] After cleaning, close the nitrogen generating assembly 6, close the cryogenic valve c, open the system cryogenic valve a, cryogenic valve b and all valves on the analysis main line except the ball valve c, introduce liquid LNG into the gasification assembly 2, and pay real-time attention to the changes in the values ​​of various sensors at the front and rear ends of the gasification assembly 2.

[0040] Set the pressure of the thermal compensation pressure regulating component 42, and select the outlet pressure of 0 to 20 Bar. If there is a specific sampling pressure requirement, the outlet pressure of the thermal compensation pressure regulating component 42 can be set to the sampling pressure.

[0041] The pressure setting range of the low-pressure regulating valve 47 is 0 to 5 Bar. In this embodiment, the analysis pressure requirement of the micro-chromatographic component is 1 Bar, that is, the outlet pressure of the low-pressure regulating valve 47 is adjusted to 1 Bar.

[0042] The flow meter 49 is adjusted, and according to the flow requirement of the micro-chromatographic component analysis, the flow meter 49 sets the flow rate to 1 L / min.

[0043] After the flow pressure stabilizes, turn on the chromatograph for continuous analysis. After the analysis values ​​of the micro-chromatographic component stabilize, continuous analysis can be started. The operating status of all sensors and electronic devices in the system can be observed in real time during the analysis process.

[0044] The control method of this embodiment is controlled by a controller, and the above-mentioned electrical components and control valves are all existing technologies. The control circuit of the controller can be realized by simple programming by technicians in this field. The provision of power is also common knowledge in this field. This article is mainly used to protect mechanical devices. The control method and circuit connection are not explained in detail in this article.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A continuous analysis system for LNG microchromatography, characterized in that: The invention comprises a gasification component (2), a buffer component (3), a pressure balance component (4), a micro-chromatographic analysis component (5) and a nitrogen generating component (6) arranged in a protective cabinet (1), wherein the gas outlet of the gasification component (2) is connected to the micro-chromatographic analysis component (5) through the buffer component (3) and the pressure balance component (4) in sequence, the gas inlet of the gasification component (2) is connected to a gas source (8) through an inlet pipe (7), and the nitrogen generating component (6) is arranged on the inlet pipe (7), the inlet end of the micro-chromatographic analysis component (5) or the outlet end of the pressure balance component (4) is also connected in series with a steel cylinder component (9), the nitrogen generating group is used for regularly purging and cleaning the analysis system, and the steel cylinder component (9) is used for cyclic sampling or external sample analysis of the micro-chromatographic analysis component (5).

2. The LNG microchromatography continuous analysis system according to claim 1, characterized in that: A polyurethane cold-insulating layer (71) is arranged on the periphery of the inlet pipe (7); and a combustible gas leakage alarm (101) is arranged in the protection cabinet (1).

3. The LNG microchromatography continuous analysis system according to claim 1, characterized in that: The gasification component (2) comprises a gasification pipeline (21), wherein a heating module (22) is arranged outside the gasification pipeline (21), a temperature sensor a (23) is arranged at the front end of the gasification pipeline (21), a temperature sensor c (24) and a pressure sensor (25) are arranged at the rear end of the gasification pipeline (21), and a temperature sensor b (26) is arranged inside the gasification pipeline (21).

4. The LNG microchromatography continuous analysis system according to claim 1, characterized in that: The buffer component (3) comprises a gasification buffer tank (31), wherein the inlet end of the gasification buffer tank (31) is connected to the outlet end of the gasification component (2), and a first one-way valve (32) is arranged between the inlet end of the gasification buffer tank (31) and the outlet end of the gasification component (2), and the passage connecting the inlet end of the gasification buffer tank (31) to the outlet end of the gasification component (2) is opened and closed by a ball valve a (33).

5. The LNG microchromatography continuous analysis system according to claim 4, characterized in that: The pressure balancing component (4) comprises a thermal compensation pressure regulating component (42); a first pipeline (41) is installed at the outlet end of the gasification buffer tank (31); the thermal compensation pressure regulating component (42) is arranged on the first pipeline (41); a ball valve b (43), a needle valve (44) and a pressure gauge (45) are also arranged on the first pipeline (41); the ball valve b (43) is located at the front end of the thermal compensation pressure regulating component (42); and the needle valve (44) and the pressure gauge (45) are located at the rear end of the thermal compensation pressure regulating component (42).

6. The LNG microchromatography continuous analysis system according to claim 5, characterized in that: The outlet end of the first pipeline (41) is connected to the inlet end of the micro-chromatographic analysis component (5) through the second pipeline (46), and a low-pressure regulating valve (47), a ball valve d (48) and a flow meter (49) are respectively arranged on the second pipeline (46), and the outlet end of the micro-chromatographic analysis component (5) is connected to the recovery pipeline (10).

7. The LNG microchromatography continuous analysis system according to claim 5, characterized in that: The cylinder assembly (9) is connected to the outlet end of the first pipe (41) or the inlet end of the second pipe (46) through the third pipe (91).

8. The LNG microchromatography continuous analysis system according to claim 1, characterized in that: The micro-chromatographic analysis component (5) is also connected in series to the gas supply component (11), and the gas medium of the gas supply component (11) can enter the micro-chromatographic analysis component (5) through the gas supply pressure regulating component (12).

9. The LNG microchromatography continuous analysis system according to claim 1, characterized in that: The nitrogen generating assembly (6) comprises an air buffer tank (61), and a positive pressure pump (62) is installed at the air inlet end of the air buffer tank (61), the air outlet end of the air buffer tank (61) is connected to a gas molecular membrane separator (64) through a fourth pipeline (63), and a filter (65) and an oil-water drying separator (66) are sequentially arranged on the fourth pipeline (63), the nitrogen outlet end of the gas molecular membrane separator (64) is connected to a nitrogen temporary storage tank (67), the impurity gas outlet end of the gas molecular membrane separator (64) is facing the air, the nitrogen temporary storage tank (67) is connected to a nitrogen bottle (69) through a fifth pipeline (68), and a delivery pump (610) and a pressure regulating valve (611) are arranged on the fifth pipeline (68), and the air outlet end of the nitrogen bottle (69) is connected to the inlet pipeline (7).

10. The LNG microchromatography continuous analysis system according to claim 5, characterized in that: The thermal compensation voltage regulating component (42) comprises a base (421), the base (421) is sleeved on the first pipe (41), a first groove (422) and a second groove (423) are provided at the bottom of the base (421), a micro heating component is provided in the first groove (422), and a temperature sensor d is provided in the second groove (423).

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