Pretreatment device for content of halogen and sulfur in hydrogen

Abstract

The utility model relates to a pretreatment device for the content of halogen and sulfur in hydrogen in the technical field of gas detection. The pretreatment device comprises a gas enrichment and separation structure, a gas combustion structure and a gas absorption structure which are connected in sequence, the gas enrichment and separation structure comprises a liquid nitrogen container; a first inlet and a first outlet are formed in the two ends of the main pipeline respectively, the first outlet is connected with the gas combustion structure, and a gas concentration pipeline capable of being placed in a liquid nitrogen container is formed on the main pipeline; the first gas mass flow controller is connected to the main pipeline and located on the side, close to the first inlet, of the gas concentration pipeline; and the heater is arranged on the outer side of the gas concentration pipeline. According to the pretreatment device, hydrogen can be completely separated from halogen and sulfur contained components, trace halogen and sulfur components in a large amount of hydrogen can be enriched to the maximum extent, the stability of detection of the content of halogen and sulfur in hydrogen is greatly improved, the detection lower limit is greatly reduced, and the detection accuracy is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of gas detection, and in particular to a pre-treatment device for halogen and sulfur content in hydrogen. Background Art

[0002] The development of fuel cells has put higher and higher requirements on the purity of hydrogen, including the testing of halogen and sulfur content. The existing standard GB / T 37244-2018 on the "Appendix A Method for Measuring the Total Chloride Content in Hydrogen" in the fuel hydrogen for proton exchange membrane fuel cell vehicles uses hydrogen to pass through water, the chloride in the sample is absorbed by the water, and then the halogen ion content in the water is measured. However, this method is only suitable for measuring inorganic chlorides and halogen ions. For organic gases such as monochloromethane and dichloromethane, since these organic gases themselves are insoluble in water, the recovery rate of organic chlorine or halogen is very low when measuring, and it cannot accurately reflect the actual total halogen content.

[0003] The existing standard ASTM D7652-2011 is a test method for determining trace hydrogen sulfide, carbonyl sulfide, methyl mercaptan, carbon disulfide and total sulfur in hydrogen fuel by gas chromatography and sulfur chemiluminescence detection. It separates the compound components in the mixture by gas chromatography and detects and quantifies the sulfur compounds by sulfur chemiluminescence detection. However, this method requires the high sensitivity of the chemiluminescence detector, which not only has high requirements on the detection conditions and equipment accuracy, but also is easily affected by some minor factors, resulting in inaccurate measurement results. Utility Model Content

[0004] In view of the problems existing in the background technology, the present application provides a pretreatment device for the halogen and sulfur content in hydrogen, which can completely separate hydrogen from the halogen and sulfur components contained therein, and can enrich the trace halogen and sulfur components in a large amount of hydrogen to the greatest extent, greatly increase the stability of the detection of the halogen and sulfur content in hydrogen, greatly reduce the detection limit, and ensure the detection accuracy.

[0005] According to one aspect of the utility model, a pretreatment device for halogen and sulfur content in hydrogen is provided, comprising a gas enrichment and separation structure, a gas combustion structure and a gas absorption structure connected in sequence; the gas enrichment and separation structure comprises: a liquid nitrogen container; a main pipeline, a first inlet and a first outlet are formed at both ends of the main pipeline respectively, the first outlet is connected to the gas combustion structure, and a gas concentration pipeline capable of placing the liquid nitrogen container is formed on the main pipeline; a first gas mass flow controller is connected to the main pipeline and is located on a side of the gas concentration pipeline close to the first inlet; a heater is installed on the outside of the gas concentration pipeline.

[0006] By using the pretreatment device for the halogen and sulfur content in hydrogen in the technical solution, the gas concentration pipeline is first placed in a liquid nitrogen container, the hydrogen to be measured is connected to the first inlet of the main pipeline, and then the opening and closing time of the first gas mass flow controller is controlled to allow a set volume of hydrogen to pass through the gas concentration pipeline of the main pipeline. The hydrogen can pass through the gas concentration pipeline in the liquid nitrogen smoothly, while other impurity gases will be frozen in the gas concentration pipeline by the liquid nitrogen. When the first gas mass flow controller is closed, the gas concentration pipeline of the main pipeline can be lifted up from the liquid nitrogen container, and then the heater is turned on to concentrate the gas. The shrink pipe is heated. During this process, the previously liquefied and frozen impurity gas is re-analyzed into gas. The gas combustion structure is used to burn this part of the gas. After being absorbed by pure water or ion chromatography mobile phase of the gas absorption structure, the ion content in the absorption liquid can be directly analyzed by ion chromatography. The pretreatment device can completely separate hydrogen from the halogen and sulfur components it contains, and can enrich trace halogen and sulfur components in a large amount of hydrogen to the greatest extent or even unlimitedly, greatly increasing the stability of the detection of halogen and sulfur content in hydrogen, greatly reducing the detection limit, and ensuring the detection accuracy.

[0007] In addition, the pre-treatment device for halogen and sulfur content in hydrogen according to the present application may also have the following additional technical features:

[0008] In some embodiments of the utility model, the pretreatment device also includes: a carrier gas container; a carrier gas pipeline, having a second inlet and a second outlet formed at both ends thereof, respectively, the second outlet being connected to the main pipeline, and the connection point between the second outlet and the main pipeline being located between the first gas mass flow controller and the gas concentration pipeline; a second gas mass flow controller being connected between the second inlet and the venting port of the carrier gas container.

[0009] In some embodiments of the utility model, the pretreatment device also includes: an electric tee, connected to the main line, located on the side of the gas concentration line close to the first outlet; the electric tee is formed with a first opening, a second opening and a third opening, the first opening and the second opening can connect the gas concentration line and the first outlet, and the first opening and the third opening can connect the gas concentration line and the outside world.

[0010] In some embodiments of the present invention, the pre-treatment device further comprises: an atmospheric branch pipe connected to the third opening.

[0011] In some embodiments of the present invention, the gas combustion structure includes: a tubular high-temperature furnace, the tubular high-temperature furnace includes a combustion tube, and both ends of the combustion tube respectively form a gas inlet and a gas outlet, and the gas inlet is connected to the first outlet.

[0012] In some embodiments of the present utility model, the pre-treatment device further comprises: a combustion tube and a main pipeline joint, connecting the gas inlet and the first outlet.

[0013] In some embodiments of the present invention, the gas absorption system is connected to the gas outlet, and is used to absorb the gas discharged from the gas outlet.

[0014] In some embodiments of the present invention, the heater is a heating wire.

[0015] The embodiment of the present application provides a pretreatment device for the halogen and sulfur content in hydrogen. Through the pretreatment device, a gas concentration pipeline is placed in a liquid nitrogen container, the hydrogen to be measured is connected to the first inlet of the main pipeline, and the electric three-way is adjusted to connect the gas concentration pipeline with the outside atmosphere; the opening and closing time of the first gas mass flow controller is controlled so that a set volume of hydrogen passes through the gas concentration pipeline of the main pipeline and is discharged into the atmosphere, and the impurity gas in the hydrogen is frozen in the gas concentration pipeline; after the first gas mass flow controller is closed, the opening and closing time of the second gas mass flow controller is controlled, and the hydrogen remaining in the main pipeline is discharged into the atmosphere through the carrier gas in the carrier gas container. Empty; continue to keep the carrier gas container open, adjust the electric tee to connect the gas concentration pipeline with the tubular high-temperature furnace, lift the gas concentration pipeline out of the liquid nitrogen container, open the second gas mass flow controller, release the carrier gas, and heat the gas concentration pipeline with the heater. The frozen impurity gas in the gas concentration pipeline is resolved into a gaseous state and brought into the tubular high-temperature furnace with the carrier gas. After combustion, the inorganic gas and organic halogen-containing gas are converted into inorganic components, which are introduced into the gas absorption system and absorbed by water or ion chromatography mobile phase; subsequently, the inorganic halogen components therein are analyzed, and then the halogen content in the hydrogen can be calculated based on the flow rate of the mass flowmeter and the opening time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0017] Figure 1 It is a schematic diagram of the overall structure of a pre-treatment device for halogen and sulfur content in hydrogen according to an embodiment of the present application.

[0018] The reference numerals in the accompanying drawings represent as follows: 1. liquid nitrogen container; 2. main pipeline; 3. first gas mass flow controller; 4. gas concentration pipeline; 5. carrier gas container; 6. carrier gas pipeline; 7. second gas mass flow controller; 8. tee; 9. electric tee; 10. atmospheric branch pipe; 12. tubular high-temperature furnace; 13. combustion tube; 14. joint between combustion tube and main pipeline; 15. gas absorption system; 16. hydrogen to be measured. DETAILED DESCRIPTION

[0019] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0020] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0021] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0022] At present, the halogen and sulfur content in hydrogen is often detected by the standard GB / T 37244-2018 "Appendix A Method for Determination of Total Chloride Content in Hydrogen" in hydrogen for proton exchange membrane fuel cell vehicles or the standard ASTM D7652-2011 using gas chromatography and sulfur chemiluminescence detection methods. It is not only difficult to effectively detect the halogen content or sulfur content in hydrogen, but also the gas chromatography combined with sulfur chemiluminescence detection method is very easy to explode when directly burning hydrogen. Although hydrogen can be burned by dilution, this will greatly reduce the injection volume of hydrogen, which will further lead to poor detection accuracy.

[0023] Therefore, the utility model provides a pretreatment device for the halogen and sulfur content in hydrogen, which uses liquid nitrogen to enrich other impurity gases based on the difference in boiling points between hydrogen and other impurity gases (as shown in Table 1 below), and then burns the enriched other impurity gases and absorbs them with pure water or ion chromatography mobile phase, and then directly uses ion chromatography to analyze the ion content in the absorption liquid.

[0024] Table 1 Boiling points of hydrogen and other impurity gases

[0025]

[0026] The following is a description of the pre-treatment device for halogen and sulfur content in hydrogen provided in an embodiment of the present application in conjunction with the accompanying drawings.

[0027] The present application discloses a pre-treatment device for halogen and sulfur content in hydrogen. Figure 1 As shown, the pretreatment device includes a gas enrichment and separation structure, a gas combustion structure and a gas absorption structure connected in sequence; wherein the gas enrichment and separation structure includes a liquid nitrogen container 1, a main line 2, a first gas mass flow controller 3 and a heater.

[0028] Among them, a first inlet and a first outlet are respectively formed at both ends of the main line 2, the first outlet is connected to the gas combustion structure, and a gas concentration pipeline 4 capable of being placed in the liquid nitrogen container 1 is formed on the main line 2; a first gas mass flow controller 3 is connected to the main line 2, and the first gas mass flow controller 3 is located on a side of the gas concentration pipeline 4 close to the first inlet; the heater is installed on the outside of the gas concentration pipeline 4.

[0029] By using the pre-treatment device in the technical solution, when it is necessary to detect the halogen and sulfur content of hydrogen, the gas concentration pipeline 4 of the main pipeline 2 can be placed in the liquid nitrogen container 1, the hydrogen 16 to be tested is connected to the first inlet of the main pipeline 2, and then the opening and closing time of the first gas mass flow controller 3 is controlled to allow a set volume of hydrogen to pass through the gas concentration pipeline 4 of the main pipeline 2. The hydrogen can pass smoothly through the gas concentration pipeline 4 in the liquid nitrogen, while other impurity gases will be frozen in the gas concentration pipeline 4 by the liquid nitrogen. When the first gas mass flow controller 3 is closed, the gas concentration pipeline 4 of the main pipeline 2 can be lifted upward from the liquid nitrogen container 1. After the gas is concentrated, the heater is turned on to heat the gas concentration pipeline 4. In this process, the previously liquefied and frozen impurity gas is re-analyzed into gas, and the gas combustion structure is used to burn this part of the gas, and after being absorbed by the pure water or ion chromatography mobile phase of the gas absorption structure, the ion content in the absorption liquid can be directly analyzed by ion chromatography. The pretreatment device can completely separate the hydrogen from the halogen and sulfur components contained therein, and can maximally or even unlimitedly enrich the trace halogen and sulfur components in a large amount of hydrogen, which greatly increases the stability of the detection of the halogen and sulfur content in hydrogen, greatly reduces the detection limit, and ensures the detection accuracy.

[0030] In this embodiment, it should be understood that the gas concentration pipeline 4 is a part of the main pipeline 2. For example, a U-shaped section can be formed by bending on the main pipeline 2, and the U-shaped section is used as the gas concentration pipeline 4. The U-shaped section can be placed in the liquid nitrogen container 1 through the mouth of the liquid nitrogen container 1, and the gas concentration pipeline 4 can be formed in any area of ​​the length of the main pipeline 2.

[0031] In some embodiments of the present invention, Figure 1 As shown, the pre-treatment device also includes a carrier gas container 5, a carrier gas pipeline 6 and a second gas mass flow controller 7.

[0032] Among them, the two ends of the carrier gas pipeline 6 respectively form a second inlet and a second outlet, the second outlet is connected to the main pipeline 2, and the connection point between the second outlet and the main pipeline 2 is located between the first gas mass flow controller 3 and the gas concentration pipeline 4; the second gas mass flow controller 7 is connected between the second inlet and the venting port of the carrier gas container 5.

[0033] When the first gas mass flow controller 3 is closed, the opening and closing time of the second gas mass flow controller 7 can be controlled, and the residual hydrogen in the main line 2 can be emptied through the carrier gas in the carrier gas container 5. In this way, when the impurity gas in the gas concentration pipeline 4 is analyzed and burned, the possibility of explosion can be greatly reduced and the safety of detection can be improved.

[0034] At the same time, when the analyzed impurity gas is burned, the impurity gas in the gas concentration pipeline 4 can continue to be delivered through the carrier gas in the carrier gas container 5, so as to fully utilize the enriched impurity gas and further improve the accuracy of detection.

[0035] In this embodiment, the carrier gas in the carrier gas container 5 includes but is not limited to argon, helium, etc.

[0036] In this embodiment, the second outlet of the carrier gas pipeline 6 and the main pipeline 2 can be connected via a tee 8 .

[0037] In some embodiments of the present invention, Figure 1 As shown, the pre-treatment device also includes an electric tee 9, which is connected to the main pipeline 2, and the electric tee 9 is located on the side of the gas concentration pipeline 4 close to the first outlet; the electric tee 9 is formed with a first opening, a second opening and a third opening, the first opening and the second opening can connect the gas concentration pipeline 4 and the first outlet, and the first opening and the third opening can connect the gas concentration pipeline 4 and the outside.

[0038] When collecting impurity gases in hydrogen, the electric tee 9 can be adjusted to a state where the first opening and the third opening are connected. At this time, the first opening and the second opening are closed. Since hydrogen is a non-toxic and harmless gas, the hydrogen can be discharged into the atmosphere after passing through the gas concentration pipeline 4 of the main line 2 through the main line 2, the first opening, the electric tee 9 and the second opening in sequence.

[0039] Furthermore, the pre-treatment device further comprises an atmospheric branch pipe 10, which is connected to the third opening. Through the atmospheric branch pipe 10, hydrogen can be discharged into a designated area or collected and utilized.

[0040] In some embodiments of the present invention, Figure 1 As shown, the gas combustion structure includes a tubular high-temperature furnace 12, and the tubular high-temperature furnace 12 includes a combustion tube 13. Two ends of the combustion tube 13 respectively form a gas inlet and a gas outlet, and the gas inlet is connected to the first outlet.

[0041] In this embodiment, after the impurity gas in the gas concentration pipeline 4 is analyzed, the gas is introduced into the combustion tube 13 through the main pipeline 2 with the carrier gas argon, and burned in the combustion tube 13. The halogen-containing and sulfur-containing components will all be converted into inorganic ions, and then they can be introduced into the absorption liquid to achieve absorption of the inorganic ions. The impurity gas burns safely and reliably in the tubular high-temperature furnace 12, ensuring the quality of inorganic ion collection.

[0042] In some embodiments of the present invention, Figure 1As shown, the pre-treatment device further includes a combustion tube and a main pipe joint 14, and the combustion tube and the main pipe joint 14 are connected to the gas inlet and the first outlet.

[0043] In some embodiments of the present invention, Figure 1 As shown, the gas absorption system 15 is connected to the gas outlet, and the gas absorption system 15 is used to absorb the gas discharged from the gas outlet.

[0044] After the impurity gas is burned, the pure water or ion chromatographic mobile phase of the gas absorption system 15 absorbs the inorganic ions, and then the ion content in the absorption liquid can be analyzed by an ion chromatographic analyzer.

[0045] In some embodiments of the present invention, Figure 1 As shown, the heater is a heating wire (not shown), which is tied to the gas concentration pipeline 4 of the main pipeline 2.

[0046] This embodiment also proposes a pretreatment method for halogen and sulfur content in hydrogen, which uses the above-mentioned pretreatment device for halogen and sulfur content in hydrogen to pretreat the halogen and sulfur content in hydrogen, and the pretreatment method includes the following steps:

[0047] First, place the gas concentration pipeline 4 of the main pipeline 2 in the liquid nitrogen container 1, connect the hydrogen gas 16 to be tested to the first inlet of the main pipeline 2, and adjust the electric tee 9 to connect the gas concentration pipeline 4 to the outside atmosphere.

[0048] Then, the opening and closing time of the first gas mass flow controller 3 is controlled so that the set volume of hydrogen passes through the gas concentration pipeline 4 of the main pipeline 2 and is discharged into the atmosphere, and the impurity gas in the hydrogen is frozen in the gas concentration pipeline 4.

[0049] After the first gas mass flow controller 3 is closed, the opening and closing time of the second gas mass flow controller 7 is controlled, and the hydrogen remaining in the main pipeline 2 is evacuated through the carrier gas in the carrier gas container 5 .

[0050] After the residual hydrogen in the main pipeline 2 is emptied, the carrier gas container is kept open, and the electric tee 9 is adjusted to connect the gas concentration pipeline 4 with the tubular high-temperature furnace 12, and the gas concentration pipeline 4 is taken out of the liquid nitrogen container 1. The heater heats the gas concentration pipeline 4, and the frozen impurity gas in the gas concentration pipeline 4 is resolved into a gaseous state and brought into the tubular high-temperature furnace 12 with the carrier gas. After combustion, the inorganic gas and the organic halogen-containing gas are converted into inorganic components, which are introduced into the gas absorption system 15 and absorbed by water or ion chromatography mobile phase. Subsequently, it is only necessary to analyze the inorganic halogen components therein, and then the halogen content in the hydrogen can be calculated based on the flow rate of the mass flowmeter and the opening time.

[0051] In some embodiments of the present invention, the flow rate of the carrier gas is set to 100-500 ml / min.

[0052] In some embodiments of the present invention, the temperature of the heater heating the gas concentration pipeline 4 is 50-100°C.

[0053] The halogen and sulfur content in hydrogen can be detected by this pretreatment method without directly burning the hydrogen. The components to be tested in the hydrogen can be enriched and the hydrogen can be removed, which can greatly increase the actual injection volume and thus greatly improve the detection accuracy.

[0054] The above is only a preferred specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A pre-treatment device for halogen and sulfur content in hydrogen, characterized in that: It includes a gas enrichment and separation structure, a gas combustion structure and a gas absorption structure connected in sequence; The gas enrichment and separation structure comprises: Liquid nitrogen container; A main pipeline, wherein a first inlet and a first outlet are respectively formed at two ends of the main pipeline, the first outlet is connected to the gas combustion structure, and a gas concentration pipeline capable of being placed in the liquid nitrogen container is formed on the main pipeline; A first gas mass flow controller, connected to the main pipeline and located on a side of the gas concentration pipeline close to the first inlet; The heater is arranged on the outside of the gas concentration pipeline.

2. The pretreatment device for halogen and sulfur content in hydrogen according to claim 1, characterized in that: Also includes: Carrier gas container; A carrier gas pipeline, with two ends of which respectively form a second inlet and a second outlet, the second outlet is connected to the main pipeline, and the connection point between the second outlet and the main pipeline is located between the first gas mass flow controller and the gas concentration pipeline; The second gas mass flow controller is connected between the second inlet and the gas outlet of the carrier gas container.

3. The pre-treatment device for halogen and sulfur content in hydrogen according to claim 2, characterized in that: Also includes: An electric tee, connected to the main pipeline, located on a side of the gas concentration pipeline close to the first outlet; The electric tee is formed with a first opening, a second opening and a third opening. The first opening and the second opening can connect the gas concentration pipeline with the first outlet, and the first opening and the third opening can connect the gas concentration pipeline with the outside.

4. The pre-treatment device for halogen and sulfur content in hydrogen according to claim 3, characterized in that: Also includes: An atmospheric branch pipe is connected to the third opening.

5. The pre-treatment device for halogen and sulfur content in hydrogen according to any one of claims 1 to 4, characterized in that: The gas combustion structure comprises: A tubular high-temperature furnace comprises a combustion tube, two ends of the combustion tube respectively form a gas inlet and a gas outlet, and the gas inlet is connected to the first outlet.

6. The pre-treatment device for halogen and sulfur content in hydrogen according to claim 5, characterized in that: Also includes: The combustion tube is connected to the main pipeline joint, connecting the gas inlet and the first outlet.

7. The pre-treatment device for halogen and sulfur content in hydrogen according to claim 5, characterized in that: The gas absorption system is connected to the gas outlet and is used for absorbing the gas discharged from the gas outlet.

8. The pre-treatment device for halogen and sulfur content in hydrogen according to any one of claims 1 to 4, characterized in that: The heater is a heating wire.

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