JPH0735933B2 - Liquefaction equipment such as helium - Google Patents
Liquefaction equipment such as heliumInfo
- Publication number
- JPH0735933B2 JPH0735933B2 JP3525586A JP3525586A JPH0735933B2 JP H0735933 B2 JPH0735933 B2 JP H0735933B2 JP 3525586 A JP3525586 A JP 3525586A JP 3525586 A JP3525586 A JP 3525586A JP H0735933 B2 JPH0735933 B2 JP H0735933B2
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- temperature
- helium
- valve
- outlet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000001307 helium Substances 0.000 title claims description 21
- 229910052734 helium Inorganic materials 0.000 title claims description 21
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 title claims description 21
- 239000007789 gas Substances 0.000 claims description 18
- 238000001514 detection method Methods 0.000 claims description 6
- 230000005494 condensation Effects 0.000 claims description 5
- 238000009833 condensation Methods 0.000 claims description 5
- 238000001816 cooling Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000006837 decompression Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
Landscapes
- Separation By Low-Temperature Treatments (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明はヘリウム等の液化装置に係り、特に液化プロセ
スに設けられるジュールトムソン弁（以下、JT弁とい
う）の前段に膨張タービンを設備する際に、プロセス制
御を適切に行なうことができるヘリウム等の液化装置に
関する。Description: TECHNICAL FIELD The present invention relates to a liquefying device for helium or the like, and particularly when installing an expansion turbine before a Joule-Thomson valve (hereinafter referred to as a JT valve) provided in a liquefying process. In addition, the present invention relates to a liquefying device for helium or the like that can appropriately perform process control.
［従来の技術］ 従来、ヘリウムや水素等を液化するための装置は第３図
に示すように、基本的には、液化すべきヘリウム等の被
冷却ガスを供給タンクａから常温で圧縮機ｂに供給し、
圧縮した被冷却ガスをその後多段に設けられた熱交換器
ｃで順次熱交換させて凝縮温度近くまで冷却し、最終的
にJT弁ｄで減圧して膨張させることにより液化して液化
タンクｅ内に貯留するようにしている。この液化プロセ
スにおける熱交換器ｃでの被冷却ガスの冷却には、液化
タンクｅ内において蒸発し若しくは液化されなかったた
めに再液化すべく圧縮機ｂへ戻される極低温の戻りガス
が利用されている。尚、液化プロセスの途中には、適当
に膨張タービンｉが配置され、戻りガスの冷却能力が低
い場合に被冷却ガスの一部を特に低温化して戻りガス側
に補充するようになっている。またｇは、圧縮機ｂで圧
縮されたばかりの被冷却ガスを液化窒素で熱交換して予
冷する予冷系である。[Prior Art] Conventionally, an apparatus for liquefying helium, hydrogen, etc. is basically a compressor b at room temperature for supplying a cooled gas such as helium to be liquefied as shown in FIG. Supply to
The compressed gas to be cooled is then sequentially heat-exchanged by heat exchangers c provided in multiple stages to be cooled to near the condensation temperature, and finally decompressed and expanded by the JT valve d to be liquefied in the liquefaction tank e. It is stored in. To cool the gas to be cooled in the heat exchanger c in this liquefaction process, the cryogenic return gas that is returned to the compressor b to be reliquefied because it has not been vaporized or liquefied in the liquefaction tank e is used. There is. An expansion turbine i is appropriately arranged in the middle of the liquefaction process, and when the return gas cooling capacity is low, a part of the gas to be cooled is particularly cooled to replenish the return gas side. Further, g is a pre-cooling system for pre-cooling the gas to be cooled, which has just been compressed by the compressor b, by heat exchange with liquefied nitrogen.
ところで従来の技術にあっては、JT弁ｄの効率が良くな
いためJT弁ｄの入口温度をできる限り下げる必要があ
り、そのために熱交換器ｃの台数を増加したり各熱交換
器ｃの容量を大きくしたり、その他予冷系ｇの効率化、
膨張タービンｉの増設等を余儀なくされ、設備の大型
化、コストアップを招くなどの問題があった。By the way, in the conventional technology, since the efficiency of the JT valve d is not good, it is necessary to lower the inlet temperature of the JT valve d as much as possible. Therefore, the number of heat exchangers c is increased or the heat exchanger c of each heat exchanger c is increased. Increase capacity, improve efficiency of other pre-cooling system g,
There was a problem that the expansion turbine i was required to be additionally installed, resulting in an increase in the size of equipment and an increase in cost.
そこでこれらの問題を解決するために第４図に示すよう
に、JT弁ｄに代えて膨張タービンｈで液化すべきガスを
減圧させることが考えられる。第２図に示すように、膨
張タービンｈの減圧（図中、実線Ａで示す）は、JT弁ｄ
の減圧（図中、破線Ｂで示す）に比べて高効率であるか
ら、タービン入口温度がJT弁入口温度より高くともJT弁
ｄと同程度の液化量を確保することができる。第２図に
示したヘリウムの状態の例では、JT弁ｄが15atmにおい
て入口温度7Kのガスを液化させる量を、膨張タービンｈ
は同じ15atmにおいて入口温度9Kで確保できる。Therefore, in order to solve these problems, it is conceivable to reduce the pressure of the gas to be liquefied by the expansion turbine h in place of the JT valve d, as shown in FIG. As shown in FIG. 2, the pressure reduction of the expansion turbine h (shown by the solid line A in the figure) is performed by the JT valve d.
Since the efficiency is higher than the decompression (shown by the broken line B in the figure), it is possible to secure a liquefaction amount similar to that of the JT valve d even if the turbine inlet temperature is higher than the JT valve inlet temperature. In the example of the helium state shown in FIG. 2, the amount that the JT valve d liquefies the gas having an inlet temperature of 7K at 15 atm is set to the expansion turbine h.
Can be secured at an inlet temperature of 9 K at the same 15 atm.
従って膨張タービンｈの採用により、上述した熱交換器
ｃの増設等の問題を解決することができる。Therefore, by adopting the expansion turbine h, it is possible to solve the above-mentioned problems such as the addition of the heat exchanger c.
［発明が解決しようとする問題点］ ところでJT弁ｄに代えて膨張タービンｈを採用した場
合、出口温度、出口圧力等タービンｈの出口側条件によ
っては、ガスがタービンｈ内で一部液化してしまう虞れ
がある。そしてこのタービンｈ内での液化は、タービン
ｈの故障原因となり、液化装置全体の運転信頼性を低下
させるという問題がある。このため膨張タービンｈを採
用するに当たり、このようなタービンｈ内でのガスの液
化を防止することが要望される。[Problems to be Solved by the Invention] By the way, when the expansion turbine h is adopted instead of the JT valve d, the gas is partially liquefied in the turbine h depending on conditions such as the outlet temperature and the outlet pressure of the turbine h. There is a risk of being lost. The liquefaction in the turbine h causes a failure of the turbine h, and there is a problem that the operation reliability of the entire liquefaction device is reduced. Therefore, when adopting the expansion turbine h, it is required to prevent the gas liquefaction in the turbine h.
［問題点を解決するための手段］ 本発明は、ヘリウム等を圧縮機で圧縮し、圧縮したその
ガスを熱交換器で凝縮温度近くまで冷却した後、ジュー
ルトムソン弁を介して減圧液化させるヘリウム等の液化
装置において、熱交換器とジュールトムソン弁との間に
設けられた膨張タービンと、膨張タービンの出口側に設
けられ出口温度を検出する温度検出手段と、膨張タービ
ンの出口側に設けられ出口圧力を検出する圧力検出手段
と、温度検出手段から入力される出口温度により当該出
口温度における蒸気圧力を算出し、算出された蒸気圧力
と圧力検出手段から入力される出口圧力とを比較して出
口圧力が算出された蒸気圧力以上に維持されるようにジ
ュールトムソン弁を作動制御する制御手段とを備えたも
のである。[Means for Solving Problems] In the present invention, helium, which is obtained by compressing helium or the like with a compressor, cooling the compressed gas to near the condensation temperature with a heat exchanger, and then liquefying it under reduced pressure via a Joule-Thomson valve In the liquefaction device such as, the expansion turbine provided between the heat exchanger and the Joule-Thomson valve, the temperature detection means provided at the outlet side of the expansion turbine to detect the outlet temperature, and provided at the outlet side of the expansion turbine. A pressure detecting means for detecting the outlet pressure and a steam pressure at the outlet temperature calculated from the outlet temperature inputted from the temperature detecting means, and comparing the calculated steam pressure with the outlet pressure inputted from the pressure detecting means. And means for controlling the operation of the Joule-Thomson valve so that the outlet pressure is maintained at the calculated vapor pressure or higher.
［作 用］ 圧縮機で圧縮され熱交換器で凝縮温度近くまで冷却され
たヘリウム等は更に膨張タービンに導かれ、膨張タービ
ンは導入されたヘリウム等を減圧して効率良く冷却し、
JT弁の入口温度（膨張タービンの出口温度）を効果的に
下げる。従ってJT弁を介してヘリウム等を適切且つ充分
に液化させ得る。またこれに際し、膨張タービンの出口
温度及び出口圧力を夫々温度検出手段及び圧力検出手段
で検出し、検出したこれら値により制御手段が次のよう
な制御を行なう。制御手段は、予め記憶された温度と圧
力との関数で与えられる蒸気圧線に基づき、検出された
出口温度において膨張タービンの出口側を気相状態に維
持できる最低限の圧力、即ち蒸気圧力を算出し、この算
出された蒸気圧力と実際に検出された出口圧力とを比較
して、出口圧力が蒸気圧力と同じか、若しくはそれより
高く維持されるようにJT弁を作動制御して、膨張タービ
ンの出口側圧力条件を、膨張タービン内でヘリウム等が
液化しないように調整するように作用する。[Operation] Helium, etc. compressed by the compressor and cooled by the heat exchanger to near the condensing temperature is further guided to the expansion turbine, which reduces the introduced helium, etc., and efficiently cools it.
Effectively lowers the JT valve inlet temperature (expansion turbine outlet temperature). Therefore, helium or the like can be appropriately and sufficiently liquefied via the JT valve. At this time, the outlet temperature and the outlet pressure of the expansion turbine are detected by the temperature detecting means and the pressure detecting means, respectively, and the control means performs the following control based on these detected values. The control means, based on the steam pressure line given as a function of temperature and pressure stored in advance, at the detected outlet temperature, the minimum pressure capable of maintaining the outlet side of the expansion turbine in the vapor phase state, that is, the steam pressure. Calculate and compare the calculated steam pressure with the actually detected outlet pressure, and operate the JT valve to control the expansion so that the outlet pressure is maintained at the same as or higher than the steam pressure. It acts to adjust the pressure condition on the outlet side of the turbine so that helium and the like are not liquefied in the expansion turbine.
［実施例］ 以下に本発明の好適一実施例を添付図面に従って詳述す
る。第１図には本発明の要部拡大系統図が示されてお
り、最終段の熱交換器１よりも上流側、及びJT弁２より
も下流側の液化プロセスは、第３図又は第４図で説明し
たものと略同様である。[Embodiment] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an enlarged system diagram of the main part of the present invention. The liquefaction process upstream of the final stage heat exchanger 1 and downstream of the JT valve 2 is shown in FIG. 3 or 4. It is almost the same as that explained in the figure.
図示するように液化すべきヘリウム等を凝縮温度近くま
で冷却する熱交換器１と、冷却されたヘリウム等を減圧
して膨張させて液化させるJT弁２との間には、膨張ター
ビン３が設けられる。この膨張タービン３は入口側が熱
交換器１に、出口側がJT弁２に接続され、熱交換器１か
ら導入されるヘリウム等を減圧膨張させて温度を下げる
ようになっている。As shown in the figure, an expansion turbine 3 is provided between the heat exchanger 1 that cools helium or the like to be liquefied to near the condensation temperature and the JT valve 2 that decompresses and expands the cooled helium or the like to liquefy it. To be The expansion turbine 3 is connected to the heat exchanger 1 on the inlet side and to the JT valve 2 on the outlet side, and is configured to decompress and expand helium and the like introduced from the heat exchanger 1 to lower the temperature.
このように構成された膨張タービン３の出口側には、JT
弁２との間にタービン３の出口温度T0及び出口圧力P0を
検出するための温度検出手段４並びに圧力検出手段５が
設けられる。これら温度検出手段４及び圧力検出手段５
は共に制御手段６に接続され、検出値T0,P0を制御手段
６に入力するようになっている。On the outlet side of the expansion turbine 3 configured in this way, JT
A temperature detecting means 4 and a pressure detecting means 5 for detecting the outlet temperature T 0 and the outlet pressure P 0 of the turbine 3 are provided between the valve 2 and the valve 2. These temperature detecting means 4 and pressure detecting means 5
Are both connected to the control means 6 and input the detected values T 0 and P 0 to the control means 6.
他方制御手段６は、主に演算部７と制御部８とから構成
され、夫々以下のように機能する。演算部７には予めヘ
リウム等液化の対象となるガスの蒸気圧線が温度の関数
（Pv＝ｆ（Ｔ））で記憶されている。そして演算部７
は、温度検出手段４から入力される出口温度T0により上
記関数を用いて当該出口温度T0における蒸気圧力Pv0を
算出するようになっている。そしてこの算出された蒸気
圧力Pv0は制御部８に入力されて処理される。制御部８
は、演算部７から入力された蒸気圧力Pv0と圧力検出手
段５から入力される出口圧力P0とを比較する。そして制
御部８は少なくとも出口圧力P0が蒸気圧力Pv0と同じか
又はそれよりも高く維持されるように相当の制御信号Ｈ
を出力する。On the other hand, the control means 6 is mainly composed of a calculation section 7 and a control section 8, and each functions as follows. The vapor pressure line of the gas to be liquefied such as helium is previously stored in the calculation unit 7 as a function of temperature (Pv = f (T)). And the arithmetic unit 7
It is adapted to calculate the steam pressure Pv0 in the outlet temperature T 0 by using the function by the outlet temperature T 0 which is input from the temperature detecting means 4. Then, the calculated vapor pressure Pv0 is input to the control unit 8 and processed. Control unit 8
Compares the outlet pressure P 0 which is input from the steam pressure Pv0 and the pressure detection means 5 which is input from the arithmetic unit 7. The control unit 8 then uses a corresponding control signal H so that at least the outlet pressure P 0 is kept equal to or higher than the steam pressure Pv 0.
Is output.
以上のように構成された制御手段６はJT弁２に接続さ
れ、制御部８からの制御信号ＨはJT弁２に入力される。
JT弁２は制御部８からの制御信号Ｈに応じて作動制御さ
れ、このJT弁２により膨張タービン３の出口側圧力条件
を、タービン３内でガスが液化しないよう調整するよう
になっている。The control means 6 configured as described above is connected to the JT valve 2, and the control signal H from the control unit 8 is input to the JT valve 2.
The operation of the JT valve 2 is controlled according to a control signal H from the control unit 8, and the JT valve 2 adjusts the outlet side pressure condition of the expansion turbine 3 so that the gas is not liquefied in the turbine 3. .
これを第２図に示したヘリウムの場合のＴ−Ｓ（温度−
エントロピ）線図で説明すると、熱交換器１で凝縮温度
Tv近くまで冷却されたガス（第１図及び第２図におい
て、Ｉで示す）は、膨張タービン３を通ることにより凝
縮が始まる蒸気圧線Ｖ近傍まで減圧低温化される（第１
図及び第２図において、IIで示す）。これに際し、ター
ビン３内ではガスの液化は生じない。そして最終的にJT
弁２で更に減圧低温化されることにより液化されること
になる（第１図及び第２図において、IIIで示す）。こ
こにJT弁２の入口側に膨張タービン３を設けたことによ
り、JT弁２の入口温度を充分に下げることができ、JT弁
２の前段の熱交換器数の減少、各熱交換器容量の減少、
予冷系の能力低減等を達成できる。In the case of helium shown in FIG.
Explaining with the entropy) diagram, the condensing temperature in the heat exchanger 1
The gas cooled to near Tv (indicated by I in FIGS. 1 and 2) is decompressed to a temperature near the vapor pressure line V where condensation starts by passing through the expansion turbine 3 (first temperature).
(Indicated as II in the figures and FIG. 2). At this time, gas liquefaction does not occur in the turbine 3. And finally JT
It is liquefied by further reducing the pressure and temperature at the valve 2 (indicated by III in FIGS. 1 and 2). By providing the expansion turbine 3 on the inlet side of the JT valve 2 here, the inlet temperature of the JT valve 2 can be sufficiently lowered, the number of heat exchangers in the preceding stage of the JT valve 2 can be reduced, and the capacity of each heat exchanger can be reduced. Decrease of
It is possible to reduce the capacity of the pre-cooling system.
［発明の効果］ 以上要するに本発明によれば次のような優れた効果を発
揮する。[Effects of the Invention] In summary, according to the present invention, the following excellent effects are exhibited.
液化プロセスの熱交換器の出口側に膨張タービンを設備
して種々の利点を発揮させる際に、膨張タービンの出口
側でJT弁との間に出口温度及び出口出力を検出する温度
検出手段並びに圧力検出手段を設け、これらからの検出
値を利用して蒸気圧線に基づきタービンの出口側条件
を、タービン内で液化を生じないようにJT弁で調整する
よようにしたので、液化による膨張タービンの故障を防
止でき、液化装置の小型化を達成しつつその運転の信頼
性を確保できる。When the expansion turbine is installed on the outlet side of the heat exchanger in the liquefaction process to exert various advantages, temperature detection means and pressure for detecting the outlet temperature and the outlet output between the JT valve and the outlet side of the expansion turbine. Since a detection means is provided and the detected values from these are used to adjust the conditions on the outlet side of the turbine based on the steam pressure line with the JT valve so that liquefaction does not occur in the turbine, the expansion turbine due to liquefaction The failure can be prevented, and the reliability of the operation can be secured while achieving the downsizing of the liquefaction device.
第１図は本発明の好適一実施例を示す要部拡大系統図、
第２図はヘリウムの液化過程を示したＴ−Ｓ（温度−エ
ントロピ）線図、第３図は従来例を示す系統図、第４図
は従来考えられた例を示す系統図である。 図中、１は熱交換器、２はJT弁、３は膨張タービン、４
は温度検出手段、５は圧力検出手段、６は制御手段であ
る。FIG. 1 is an enlarged system diagram of an essential part showing a preferred embodiment of the present invention.
FIG. 2 is a T-S (temperature-entropy) diagram showing the liquefaction process of helium, FIG. 3 is a system diagram showing a conventional example, and FIG. 4 is a system diagram showing a conventionally considered example. In the figure, 1 is a heat exchanger, 2 is a JT valve, 3 is an expansion turbine, 4
Is temperature detecting means, 5 is pressure detecting means, and 6 is control means.
Claims (1)
のガスを熱交換器で凝縮温度近くまで冷却した後、ジュ
ールトムソン弁を介して減圧液化させるヘリウム等の液
化装置において、上記熱交換器と上記ジュールトムソン
弁との間に設けられた膨張タービンと、該膨張タービン
の出口側に設けられ出口温度を検出する温度検出手段
と、上記膨張タービンの出口側に設けられ出口圧力を検
出する圧力検出手段と、上記温度検出手段から入力され
る温度により蒸気圧力を算出し、算出された該蒸気圧力
と上記圧力検出手段から入力される圧力とを比較して上
記ジュールトムソン弁を作動制御する制御手段とを備え
たことを特徴とするヘリウム等の液化装置。1. A liquefying device for helium or the like, wherein helium or the like is compressed by a compressor, and the compressed gas is cooled by a heat exchanger to near the condensation temperature, and then liquefied under reduced pressure through a Joule-Thomson valve. Turbine provided between the container and the Joule-Thomson valve, temperature detecting means provided on the outlet side of the expansion turbine to detect the outlet temperature, and outlet pressure provided on the outlet side of the expansion turbine to detect the outlet pressure. The steam pressure is calculated from the pressure input means and the temperature input from the temperature detection means, and the calculated steam pressure is compared with the pressure input from the pressure detection means to control the operation of the Joule-Thomson valve. A liquefying device for helium or the like, which is provided with a control means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3525586A JPH0735933B2 (en) | 1986-02-21 | 1986-02-21 | Liquefaction equipment such as helium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3525586A JPH0735933B2 (en) | 1986-02-21 | 1986-02-21 | Liquefaction equipment such as helium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62196560A JPS62196560A (en) | 1987-08-29 |
| JPH0735933B2 true JPH0735933B2 (en) | 1995-04-19 |
Family
ID=12436710
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3525586A Expired - Lifetime JPH0735933B2 (en) | 1986-02-21 | 1986-02-21 | Liquefaction equipment such as helium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0735933B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2025012357A (en) * | 2023-07-13 | 2025-01-24 | 三菱重工業株式会社 | Liquefaction device and liquefaction method |
| JP2025012358A (en) * | 2023-07-13 | 2025-01-24 | 三菱重工業株式会社 | Liquefaction device and liquefaction method |
-
1986
- 1986-02-21 JP JP3525586A patent/JPH0735933B2/en not_active Expired - Lifetime
Non-Patent Citations (1)
| Title |
|---|
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62196560A (en) | 1987-08-29 |
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