Trace impurity purification system

Abstract

According to the trace impurity purification system provided by the utility model, during purification of the first adsorber, helium passes through the second pneumatic control valve, the first adsorber and the pneumatic switch valve, and during regeneration of the first adsorber, the second pneumatic control valve and the third pneumatic switch valve are closed; high-pressure normal-temperature helium enters the first heat exchanger through the first pneumatic control valve and the second pneumatic switch valve, and enters the helium low-temperature system low-pressure pipeline after being subjected to heat exchange through the first heat exchanger. Low-temperature and high-pressure helium in the first adsorber enters a third heat exchanger through a sixth pneumatic switch valve and then enters a helium recovery air bag through a fifth pneumatic control valve, the vacuum pump performs vacuum extraction, according to the logic, when the second adsorber works, the first adsorber regenerates, and the operation is repeated, so that the helium is recovered. Automatic control over trace impurity purification, purification system regeneration switching and the like is achieved, automatic continuous operation of a large helium low-temperature system can be achieved, and the automation degree of the system is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of low-temperature refrigeration and adsorption, in particular to a trace impurity purification system. Background Art

[0002] Since the beginning of the 20th century, the progress of science and technology has brought about the development of low-temperature superconducting technology. Low-temperature superconducting technology is inseparable from large-scale helium cryogenic systems. The two complement and promote each other. In these large-scale helium cryogenic systems, in order to ensure the reliable operation of the system, the purity of helium is an important factor. Therefore, in the helium cryogenic system, 80K and 10K adsorbers are generally set up to adsorb trace amounts of impurity gases such as nitrogen, oxygen, argon, hydrogen and neon in high-purity helium. After the adsorber is saturated with impurity gases, in order to ensure the subsequent continuous operation of the large-scale helium cryogenic system, it is very necessary to activate and regenerate the adsorber.

[0003] In traditional large-scale helium cryogenic systems, especially cryogenic refrigeration systems, closed cycles are generally used, and open cycles are generally used for liquefaction systems. In a closed cycle, after the system is purified, other impurities in the circulating medium helium are almost negligible. For long-term helium refrigeration systems, a single purification system (adsorber) can meet the requirements, and switching is not required, and the regeneration of the purification system can be arranged during the overhaul of the entire system. Therefore, there is no problem of automatic control of purification and regeneration of the purification system. For long-term continuous operation of the open cycle, it is necessary to continuously replenish high-purity helium that meets the requirements of national standards. Although switching trace impurity purification and purification systems (adsorbers) are indispensable, the regeneration of the adsorber can be arranged during the overhaul of the system, or the manual regeneration of the adsorber can be performed occasionally during online operation, without involving automatic control. In the natural gas helium extraction project, the high-purity helium from the refining workshop sometimes does not meet the requirements of national standards. In the continuous natural gas helium extraction project with a high degree of automation, the automatic control system for switching trace impurity purification and regeneration of the purification system (adsorber) is particularly important. Utility Model Content

[0004] In view of this, it is necessary to provide an automated trace impurity purification system that can realize continuous operation of a large helium cryogenic system in order to address the current technical problem of low degree of automatic control of trace impurity purification and purification system (adsorber) regeneration.

[0005] In order to solve the above problems, the utility model adopts the following technical solutions:

[0006] One of the purposes of the utility model is to provide a trace impurity purification system, comprising:

[0007] A first adsorber (AD1), a second adsorber (AD2), a second pneumatic regulating valve (CV04) disposed at an air inlet of the first adsorber (AD1), a third pneumatic switch valve (CV05) disposed at an air outlet of the first adsorber (AD1), a third pneumatic regulating valve (CV06) disposed at an air inlet of the second adsorber (AD2), a fourth pneumatic switch valve (CV07) disposed at an air outlet of the second adsorber (AD2), a first pneumatic regulating valve (CV01), a second pneumatic regulating valve (CV04), a third pneumatic switch valve (CV05) disposed at an air outlet of the first adsorber (AD1), a third pneumatic regulating valve (CV06) disposed at an air inlet of the second adsorber (AD2), a fourth pneumatic switch valve (CV07) disposed at an air outlet of the second adsorber (AD2), A third pneumatic regulating valve (CV06), a fourth pneumatic regulating valve (CV10), a fifth pneumatic regulating valve (CV11), a first pneumatic switch valve (CV02), a second pneumatic switch valve (CV03), a third pneumatic switch valve (CV05), a fourth pneumatic switch valve (CV07), a fifth pneumatic switch valve (CV08), a sixth pneumatic switch valve (CV09), one end of the fourth pneumatic regulating valve (CV10) is connected to a vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump;

[0008] When the first adsorber (AD1) is purified, the helium passes through the second pneumatic regulating valve (CV04), the first adsorber (AD1) and the third pneumatic switch valve (CV05). When the first adsorber (AD1) is regenerated, the second pneumatic regulating valve (CV04) and the third pneumatic switch valve (CV05) are closed, and the high-pressure and normal-temperature helium passes through the first pneumatic regulating valve (CV01) and the second pneumatic switch valve (CV03) and enters the first heat exchanger (HEX01). After heat exchange in the first heat exchanger (HEX01), it enters the low-pressure pipeline of the helium cryogenic system. The low-temperature and high-pressure helium in the first adsorber (AD1) enters the third heat exchanger (HEX03) through the sixth pneumatic switch valve (CV09), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11). One end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump.

[0009] When the second adsorber (AD2) is purified, the helium passes through the third pneumatic regulating valve (CV06), the second adsorber (AD2) and the fourth pneumatic switch valve (CV07). When the second adsorber (AD2) is regenerated, the third pneumatic regulating valve (CV06) and the fourth pneumatic switch valve (CV07) are closed, and the high-pressure and normal-temperature helium passes through the first pneumatic regulating valve (CV01) and the first pneumatic switch valve (CV02) and enters the second heat exchanger (HEX02). After heat exchange in the second heat exchanger (HEX02), it enters the low-pressure pipeline of the helium cryogenic system. The low-temperature and high-pressure helium in the second adsorber (AD2) enters the third heat exchanger (HEX03) through the fifth pneumatic switch valve (CV08), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11). One end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump.

[0010] In some embodiments, the invention further comprises a compressor (110), a heat exchanger group (120) composed of a plurality of heat exchangers connected in series, a turbine expansion unit (130) and a liquid helium dewar (140); one end of the compressor (110) is connected to one end of the heat exchanger group (120) via a pipeline; the other end of the compressor (110) is connected to the liquid helium dewar (140) via a pipeline; the liquid helium dewar (140) is connected to the other end of the heat exchanger group (120) via a pipeline; and the turbine expansion unit (130) is arranged on the pipeline.

[0011] In some embodiments, the heat exchanger group (120) is composed of a plurality of heat exchangers connected in series.

[0012] In some of the embodiments, the turboexpander unit (130) is composed of two turboexpanders connected in series.

[0013] In some embodiments, a first low-temperature thermometer (T1) and a second low-temperature thermometer (T2) are respectively disposed on the first adsorber (AD1) and the second adsorber (AD2).

[0014] In some of the embodiments, a first pressure sensor (P1) is further provided on the pipeline between the second pneumatic regulating valve (CV04) and the first adsorber (AD1).

[0015] In some of the embodiments, a second pressure sensor (P2) is further provided on the pipeline between the third pneumatic regulating valve (CV06) and the second adsorber (AD2).

[0016] The utility model adopts the above technical solution, and its beneficial effects are as follows:

[0017] The utility model provides a trace impurity purification system. When the first adsorber (AD1) is purified, helium passes through the second pneumatic regulating valve (CV04), the first adsorber (AD1) and the pneumatic switch valve (CV05). When the first adsorber (AD1) is regenerated, the second pneumatic regulating valve (CV04) and the third pneumatic switch valve (CV05) are closed, and high-pressure and room-temperature helium passes through the first pneumatic regulating valve (CV01) and the second pneumatic switch valve (CV03) and enters the first heat exchanger (HEX01). After heat exchange in the first heat exchanger (HEX01), the helium enters the low-pressure pipeline of the helium cryogenic system. The low-temperature and high-pressure helium in the first adsorber (AD1) enters the third heat exchanger (HEX03) through the sixth pneumatic switch valve (CV09), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11). One end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump. According to the above logic, when the second adsorber (AD2) is working, the first adsorber (AD1) is regenerated, and so on, to achieve automatic control such as trace impurity purification and purification system (adsorber) regeneration switching, which can realize automatic continuous operation of large helium cryogenic systems and improve the automation of the system. The low-temperature helium in the main part of the adsorber is provided with a vaporizer, namely HEX03, in the regeneration pipeline, thereby avoiding the use of a heater in the form of electric heating, avoiding electricity consumption, and improving the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments of the utility model or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic structural diagram of a trace impurity purification system provided in one embodiment of the utility model.

[0020] Figure 2 A schematic diagram of an adsorber regeneration control interface provided in one embodiment of the utility model. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0022] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "horizontal", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations 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 a limitation on the present invention.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0025] See also Figure 1 The present invention provides a trace impurity purification system, comprising: a first adsorber (AD1), a second adsorber (AD2), a second pneumatic regulating valve (CV04) disposed at an air inlet of the first adsorber (AD1), a third pneumatic switch valve (CV05) disposed at an air outlet of the first adsorber (AD1), a third pneumatic regulating valve (CV06) disposed at an air inlet of the second adsorber (AD2), a fourth pneumatic switch valve (CV07) disposed at an air outlet of the second adsorber (AD2), a first pneumatic regulating valve (CV01), a second pneumatic regulating valve (CV02), a second pneumatic regulating valve (CV03) disposed at an air inlet of the second adsorber (AD2), a third pneumatic regulating valve (CV04) disposed at an air outlet of the first adsorber (AD1), a third pneumatic regulating valve (CV05) disposed at an air inlet of the second adsorber (AD2), a fourth pneumatic switch valve (CV07) disposed at an air outlet of the second adsorber (AD2), a first pneumatic regulating valve (CV01), a second pneumatic regulating valve (CV02), a second pneumatic regulating valve (CV03) disposed at an air inlet of the second adsorber (AD2), a third pneumatic regulating valve (CV06) disposed at an air inlet of the second adsorber (AD2), a third pneumatic regulating valve (CV03) disposed at an air outlet of the second adsorber (AD2), a third pneumatic regulating valve (CV03) disposed at an air inlet ... outlet of the second adsorber (AD2), a third pneumatic regulating valve (CV03) disposed at an air in a pneumatic regulating valve (CV04), a third pneumatic regulating valve (CV06), a fourth pneumatic regulating valve (CV10), a fifth pneumatic regulating valve (CV11), a first pneumatic switch valve (CV02), a second pneumatic switch valve (CV03), a third pneumatic switch valve (CV05), a fourth pneumatic switch valve (CV07), a fifth pneumatic switch valve (CV08), a sixth pneumatic switch valve (CV09), one end of the fourth pneumatic regulating valve (CV10) is connected to a vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump.

[0026] When the first adsorber (AD1) is purified, the helium passes through the second pneumatic regulating valve (CV04), the first adsorber (AD1) and the third pneumatic switch valve (CV05); when the first adsorber (AD1) is regenerated, the second pneumatic regulating valve (CV04) and the third pneumatic switch valve (CV05) are closed, and the high-pressure and room-temperature helium passes through the first pneumatic regulating valve (CV01) and the second pneumatic switch valve (CV03) and enters the first heat exchanger (HEX01). After heat exchange in the first heat exchanger (HEX01), the helium enters the low-pressure pipeline of the helium cryogenic system; the low-temperature and high-pressure helium in the first adsorber (AD1) enters the third heat exchanger (HEX03) through the sixth pneumatic switch valve (CV09), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11); one end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump;

[0027] When the second adsorber (AD2) is purified, the helium passes through the third pneumatic regulating valve (CV06), the second adsorber (AD2) and the fourth pneumatic switch valve (CV07). When the second adsorber (AD2) is regenerated, the third pneumatic regulating valve (CV06) and the fourth pneumatic switch valve (CV07) are closed, and the high-pressure normal-temperature helium passes through the first pneumatic regulating valve (CV01) and the first pneumatic switch valve (CV02) and enters the second heat exchanger (HEX02). After heat exchange in the second heat exchanger (HEX02), it enters the low-pressure pipeline of the helium cryogenic system. The low-temperature and high-pressure helium in the second adsorber (AD2) then enters the third heat exchanger (HEX03) through the fifth pneumatic switch valve (CV08), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11). One end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump.

[0028] Specifically, during the purification process, when AD1 is working, the pneumatic control valve CV04 is fully opened, and the pneumatic switch valve CV05 is fully opened. At the same time, the outlet pneumatic switch valve CV07 of adsorber AD2 is fully opened, and the inlet pneumatic control valve CV06 is opened to a small opening of about 4% to achieve continuous precooling of adsorber AD2. During the operation of the helium cryogenic system, adsorbers AD1 and AD2 cannot be regenerated at the same time.

[0029] See also Figure 2, which is a schematic diagram of the adsorber regeneration control interface provided in this embodiment. First, set the adsorber regeneration time interval to 100h in the adsorber regeneration control interface. When the adsorber regeneration is reached, the adsorber AD1 automatically regenerates, the regeneration button becomes pressed, and the "regeneration" and "regeneration end" change color. Slowly open CV06 to 100% opening, and at the same time, slowly close CV04 to an opening of 0. When the CV04 opening is 0, immediately open the pneumatic switch valve CV09, and open the pneumatic regulating valve CV11 to about 8% opening, and then slowly open the CV11 opening until the pressure P1 of the adsorber AD1 is 2-3bara. At the same time, open the pneumatic switch valve CV03, and slowly open the pneumatic regulating valve CV01, and adjust CV11 at the same time, so that the pressure of the adsorber AD1 is maintained at 2-3bara. Pay attention to the temperature T1 of the adsorber AD1. When the temperature T1 is around 100K, close CV01 and CV03 at the same time. Slowly adjust the opening of CV11 until the pressure in the adsorber AD1 no longer changes. At the same time, turn on the vacuum pump, close CV11, and open CV10. Continue to draw vacuum for about 40 minutes. Turn off CV10 and the vacuum pump. Open CV04 to about 4% opening, and when the pressure of adsorber AD1 reaches atmospheric pressure, close CV08. When the pressure of adsorber AD1 reaches the working pressure, fully open CV05. At this point, the regeneration is over, and the regeneration button returns to the initial unpressed state, and "Regeneration" and "End of Regeneration" change color. That is, the colors of "Regeneration" and "End of Regeneration" are inconsistent on the same interface. The green font indicates that it is in this state, and the red font indicates that the state is over. When the regeneration time interval of the adsorber is reached again, according to the above logic, adsorber AD2 works and adsorber AD1 regenerates, and so on, to achieve automatic control such as purification of trace impurities and regeneration switching of the purification system (adsorber).

[0030] It can be understood that the trace impurity purification system provided in this embodiment includes a first adsorber (AD1) and a second adsorber (AD2), and the control logic and automatic control system for the purification of multiple adsorbers in parallel or the purification of 80K adsorbers and the regeneration of the purification system (adsorber) are consistent with the technical solutions of the above-mentioned embodiments and will not be repeated here.

[0031] In some embodiments, the invention further comprises a compressor (110), a heat exchanger group (120) composed of a plurality of heat exchangers connected in series, a turbine expansion unit (130) and a liquid helium dewar (140); one end of the compressor (110) is connected to one end of the heat exchanger group (120) via a pipeline; the other end of the compressor (110) is connected to the liquid helium dewar (140) via a pipeline; the liquid helium dewar (140) is connected to the other end of the heat exchanger group (120) via a pipeline; and the turbine expansion unit (130) is arranged on the pipeline.

[0032] In some embodiments, the heat exchanger group (120) is composed of a plurality of heat exchangers connected in series.

[0033] In some of the embodiments, the turboexpander unit (130) is composed of two turboexpanders connected in series.

[0034] In some embodiments, the first adsorber (AD1) and the second adsorber (AD2) are provided with a first low-temperature thermometer (T1) and a second low-temperature thermometer (T2), respectively, for obtaining the temperature of the first adsorber (AD1) and the second adsorber (AD2) in real time. The first low-temperature thermometer (T1) and the second low-temperature thermometer (T2) are low-temperature thermometers in the 10K temperature range.

[0035] In some of the embodiments, a first pressure sensor (P1) is further provided on the pipeline between the second pneumatic regulating valve (CV04) and the first adsorber (AD1) for obtaining the pressure on the pipeline in real time.

[0036] In some of the embodiments, a second pressure sensor (P2) is further provided on the pipeline between the third pneumatic regulating valve (CV06) and the second adsorber (AD2) for obtaining the pressure on the pipeline in real time.

[0037] The trace impurity purification system provided by the above embodiment of the utility model can realize automatic control of trace impurity purification and regeneration switching of the purification system (adsorber), and can realize automatic continuous operation of a large helium cryogenic system, thereby improving the automation level of the system. The low-temperature helium gas in the main part of the adsorber is provided with a vaporizer, namely HEX03, in the regeneration pipeline, thereby avoiding the use of an electric heating heater, avoiding electricity consumption, and improving the reliability of the system.

[0038] It can be understood that the technical features of the above-described embodiments can be arbitrarily combined. In order to make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0039] The above are only preferred embodiments of the present invention, and only specifically describe the technical principles of the present invention. These descriptions are only for the purpose of explaining the principles of the present invention, and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanation here, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention, and other specific implementation methods of the present invention that can be associated with by technicians in this field without creative labor, should be included in the scope of protection of the present invention.

Claims

1. A trace impurity purification system, It is characterized in that include: a first adsorber (AD1), a second adsorber (AD2), a second pneumatic regulating valve (CV04) disposed at an air inlet of the first adsorber (AD1), a third pneumatic switch valve (CV05) disposed at an air outlet of the first adsorber (AD1), a third pneumatic regulating valve (CV06) disposed at an air inlet of the second adsorber (AD2), a fourth pneumatic switch valve (CV07) disposed at an air outlet of the second adsorber (AD2), a first pneumatic regulating valve (CV01), a second pneumatic regulating valve (CV04), A third pneumatic regulating valve (CV06), a fourth pneumatic regulating valve (CV10), a fifth pneumatic regulating valve (CV11), a first pneumatic switch valve (CV02), a second pneumatic switch valve (CV03), a third pneumatic switch valve (CV05), a fourth pneumatic switch valve (CV07), a fifth pneumatic switch valve (CV08), a sixth pneumatic switch valve (CV09), one end of the fourth pneumatic regulating valve (CV10) is connected to a vacuum pump and the other end is connected to a third heat exchanger (HEX03) for vacuum extraction through the vacuum pump; When the first adsorber (AD1) is purified, the helium passes through the second pneumatic regulating valve (CV04), the first adsorber (AD1) and the third pneumatic switch valve (CV05); when the first adsorber (AD1) is regenerated, the second pneumatic regulating valve (CV04) and the third pneumatic switch valve (CV05) are closed, and the high-pressure and room-temperature helium passes through the first pneumatic regulating valve (CV01) and the second pneumatic switch valve (CV03) and enters the first heat exchanger (HEX01), and after heat exchange in the first heat exchanger (HEX01), enters the low-pressure pipeline of the helium cryogenic system; the low-temperature and high-pressure helium in the first adsorber (AD1) enters the third heat exchanger (HEX03) through the sixth pneumatic switch valve (CV09), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11); one end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump; When the second adsorber (AD2) is purified, the helium passes through the third pneumatic regulating valve (CV06), the second adsorber (AD2) and the fourth pneumatic switch valve (CV07); when the second adsorber (AD2) is regenerated, the third pneumatic regulating valve (CV06) and the fourth pneumatic switch valve (CV07) are closed, and the high-pressure and room-temperature helium passes through the first pneumatic regulating valve (CV01) and the first pneumatic switch valve (CV02) and enters the second heat exchanger (HEX02). After heat exchange in the second heat exchanger (HEX02), the helium enters the low-pressure pipeline of the helium cryogenic system; the low-temperature and high-pressure helium in the second adsorber (AD2) enters the third heat exchanger (HEX03) through the fifth pneumatic switch valve (CV08), and then enters the helium recovery airbag through the fifth pneumatic regulating valve (CV11); one end of the fourth pneumatic regulating valve (CV10) is connected to the vacuum pump and the other end is connected to the third heat exchanger (HEX03) for vacuum extraction through the vacuum pump.

2. The trace impurity purification system according to claim 1, It is characterized in that The invention also comprises a compressor (110), a heat exchanger group (120) composed of a plurality of heat exchangers connected in series, a turbine expansion unit (130) and a liquid helium dewar (140), wherein one end of the compressor (110) is connected to one end of the heat exchanger group (120) via a pipeline, the other end of the compressor (110) is connected to the liquid helium dewar (140) via a pipeline, the liquid helium dewar (140) is connected to the other end of the heat exchanger group (120) via a pipeline, and the turbine expansion unit (130) is arranged on the pipeline.

3. The trace impurity purification system according to claim 2, It is characterized in that The heat exchanger group (120) is composed of a plurality of heat exchangers connected in series.

4. The trace impurity purification system according to claim 2, It is characterized in that The expansion unit (130) is composed of two turbine expanders connected in series.

5. The trace impurity purification system according to claim 1, It is characterized in that The first adsorber (AD1) and the second adsorber (AD2) are provided with a first low-temperature thermometer (T1) and a second low-temperature thermometer (T2), respectively.

6. The trace impurity purification system according to claim 1, It is characterized in that A first pressure sensor (P1) is also provided on the pipeline between the second pneumatic regulating valve (CV04) and the first adsorber (AD1).

7. The trace impurity purification system according to claim 1, It is characterized in that A second pressure sensor (P2) is also provided on the pipeline between the third pneumatic regulating valve (CV06) and the second adsorber (AD2).

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