JPH0434391Y2 - - Google Patents
Info
- Publication number
- JPH0434391Y2 JPH0434391Y2 JP1984104504U JP10450484U JPH0434391Y2 JP H0434391 Y2 JPH0434391 Y2 JP H0434391Y2 JP 1984104504 U JP1984104504 U JP 1984104504U JP 10450484 U JP10450484 U JP 10450484U JP H0434391 Y2 JPH0434391 Y2 JP H0434391Y2
- Authority
- JP
- Japan
- Prior art keywords
- waste gas
- air
- nitrogen
- pipe
- condenser
- 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
Links
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 66
- 229910052757 nitrogen Inorganic materials 0.000 claims description 33
- 239000002912 waste gas Substances 0.000 claims description 19
- 239000007788 liquid Substances 0.000 claims description 12
- 238000004519 manufacturing process Methods 0.000 claims description 12
- 238000005057 refrigeration Methods 0.000 claims description 8
- 239000007789 gas Substances 0.000 claims description 7
- 239000000284 extract Substances 0.000 claims description 4
- 238000004821 distillation Methods 0.000 claims 1
- 238000000605 extraction Methods 0.000 claims 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 239000003463 adsorbent Substances 0.000 description 5
- 229930195733 hydrocarbon Natural products 0.000 description 5
- 150000002430 hydrocarbons Chemical class 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 150000001722 carbon compounds Chemical class 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000002808 molecular sieve Substances 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 150000002829 nitrogen Chemical class 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Landscapes
- Separation By Low-Temperature Treatments (AREA)
Description
【考案の詳細な説明】
本考案は、空気を液化精留して窒素を製造する
装置に関するものである。[Detailed Description of the Invention] The present invention relates to an apparatus for producing nitrogen by liquefying and rectifying air.
空気を液化精留して酸素、窒素を製造する際、
原料空気中の二酸化炭素、炭化水素等は精留塔に
導入される以前に、熱交換器または蓄冷器で冷却
されることにより水分とともに除去されるが微量
のものが精留塔に入ることは避けられない。この
ような炭素化合物が製品中に混入することは品質
上好ましくないし、さらに微量ではあつてもこれ
が精留塔内に蓄積すると爆発の危険がある。その
ためたとえば複式精留塔では中圧精留塔の塔底液
を低圧精留塔へ導入する前にフイルター（吸着
器）を設け、二酸化炭素、炭化水素類を捕集して
いたし、単式精留塔でもこれらの濃縮された液体
留分をとり出して、フイルターを通過させてい
た。 When air is liquefied and rectified to produce oxygen and nitrogen,
Carbon dioxide, hydrocarbons, etc. in the feed air are cooled in a heat exchanger or regenerator before being introduced into the rectification tower, and are removed together with moisture, but trace amounts of them do not enter the rectification tower. Inevitable. Contamination of such carbon compounds in the product is not desirable in terms of quality, and furthermore, if even a small amount of carbon compounds is accumulated in the rectification column, there is a risk of explosion. For this reason, for example, in a double rectification column, a filter (adsorber) was installed to collect carbon dioxide and hydrocarbons before introducing the bottom liquid from the medium pressure rectification column into the low pressure rectification column; These concentrated liquid fractions were also taken out from the tower and passed through a filter.
しかしながら、このような方法では常に定期的
にフイルター内の吸着剤の再生を行わねばならな
いし、吸着剤の機能が低下したときは、吸着剤の
交換をせねばならないので、操作が煩雑になると
いう欠点があり、さらに寒冷を損失する欠点があ
るため、本出願人はさきに、「空気を液化精留し
て窒素を製造する方法において、中圧精留塔上部
にある凝縮器からとり出される炭化水素、二酸化
炭素等の濃縮された酸素に富む液体を熱交換器に
導き、ここで常温の原料空気の一部との間接熱交
換によつて瞬間的に気化させた後大気中に放出
し、冷却された空気は、中圧精留塔上部の凝縮器
からとり出された後に主熱交換器で原料空気の冷
却に用いられた酸素に富むガスと合流した後膨張
され、主熱交換器において原料空気と間接熱交換
して常温にまで加温してから廃ガスとして大気中
に放出されることを特徴とする窒素製造方法」を
発明した（特公昭54−39830号）。 However, with this method, the adsorbent in the filter must be regularly regenerated, and when the adsorbent's function deteriorates, the adsorbent must be replaced, making the operation complicated. Because of the disadvantages and the disadvantage of loss of refrigeration, the applicant has previously proposed that ``In the method of producing nitrogen by liquefaction rectification of air, Concentrated oxygen-rich liquids such as hydrocarbons and carbon dioxide are introduced into a heat exchanger, where they are instantaneously vaporized by indirect heat exchange with a portion of the feed air at room temperature, and then released into the atmosphere. , the cooled air is taken out from the condenser at the top of the medium-pressure rectification column, combines with the oxygen-rich gas used to cool the feed air in the main heat exchanger, and is expanded. Invented a method for producing nitrogen, which involves indirect heat exchange with raw material air to warm it to room temperature and then releasing it into the atmosphere as waste gas (Japanese Patent Publication No. 39830/1983).
この窒素製造方法により、従来のような吸着剤
によるフイルターが不要となるので、吸着剤の再
生、交換という操作もまた必要がなくなるし、と
り出されて大気中に放出される炭化水素等の濃縮
された液体留分の寒冷も完全に回収できる。しか
も、装置的には主熱交換器、精留塔とともに炭化
水素類気化のための熱交換器も一体の保冷箱内に
収納し、従来の断熱材充填よりはるかに断熱効率
の優れた真空断熱または粉末充填真空断熱を施す
ることが可能となる等の大きな利点がある。 This nitrogen production method eliminates the need for conventional adsorbent filters, which eliminates the need for adsorbent regeneration and replacement operations, and reduces the concentration of hydrocarbons, etc. that are extracted and released into the atmosphere. The refrigeration of the liquid fraction produced can also be completely recovered. What's more, the main heat exchanger, rectification column, and heat exchanger for vaporizing hydrocarbons are housed in an integrated cold box, providing vacuum insulation with much better insulation efficiency than conventional insulation material filling. Also, it has great advantages such as being able to perform powder-filled vacuum insulation.
本考案者は前述の窒素製造方法を実施するため
に好適な窒素製造装置を開発するため種々検討、
実験の結果、本考案装置の開発に成功したもので
あり、本考案装置原料空気を１〜３Kg／cm2に圧縮
する圧縮機、精製器、製品ガス及び廃ガスと熱交
換して原料空気を液化点まで冷却する熱交換器、
冷却された空気を精留する精留塔、精留塔頂部か
ら製品窒素を取出す管路、精留塔上部のコンデン
サから廃ガスを取出す管路、熱交換器に送られる
廃ガスに寒冷を付加する手段を含む窒素製造装置
において、精留塔底部と該精留塔上部コンデンサ
とを連通する管路に、内部に穴を有する膨張弁か
又はオリフイスを設け、かつ逆止弁を有する廃ガ
ス管路を大気開放型とすることを特徴とし、いわ
ゆる窒素製造装置のうち、コールドボツクス内の
流体のラインに仕切り個所に設けず末端を大気開
放とし、装置の運転停止時等にもコールドボツク
ス内部の機器に異常な圧力がかゝることを防止し
うる特徴を有するものである。 The present inventor conducted various studies in order to develop a nitrogen production device suitable for carrying out the above-mentioned nitrogen production method.
As a result of experiments, we succeeded in developing the device of the present invention, which consists of a compressor that compresses the raw air to 1 to 3 kg/ cm2 , a purifier, and a heat exchanger with the product gas and waste gas to convert the raw air into heat exchanger to cool to liquefaction point,
A rectification column that rectifies the cooled air, a pipe line that extracts product nitrogen from the top of the rectification column, a line that extracts waste gas from the condenser at the top of the rectification column, and adds refrigeration to the waste gas sent to the heat exchanger. In a nitrogen production apparatus including a means for It is characterized by the fact that the line is open to the atmosphere, and in so-called nitrogen production equipment, the fluid line inside the cold box is not installed at a partition point, but the end is opened to the atmosphere, so that the inside of the cold box can be opened even when the equipment is stopped, etc. It has a feature that can prevent abnormal pressure from being applied to the equipment.
添付図面は、単式精留塔によつて窒素を製造す
る本考案装置の一例を示すフローシートである。 The attached drawing is a flow sheet showing an example of the apparatus of the present invention for producing nitrogen using a single rectification column.
添付図面に示す本考案装置の特徴的構成は、精
留塔５の底部に分離された液体空気を該精留塔上
部の窒素コンデンサ７に供給する管路１０に、膨
張弁としては閉であつても流体の流通を可能にす
る公知の構造の内部に穴を有する膨張弁か又はオ
リフイス６を設けること及び廃ガス管路１１に逆
止弁８を設けることにより装置の運転停止時等に
装置で圧力が上昇することがあつても、これらの
穴明き膨張弁又はオリフイス６及び逆止弁８を経
て大気に放出されるので装置内の圧力上昇を防止
できるし、外部からの不純物の混入、逆流をも防
止し得るのである。 The characteristic configuration of the device of the present invention shown in the accompanying drawings is that a pipe 10 that supplies the liquid air separated at the bottom of the rectification column 5 to the nitrogen condenser 7 at the top of the rectification column is connected to a closed expansion valve. By providing an expansion valve or orifice 6 with a hole in the interior of the well-known structure that allows fluid to flow even when the device is in operation, and by providing a check valve 8 in the waste gas pipe 11, the device can be used when the device is stopped, etc. Even if the pressure rises in the process, it is released to the atmosphere through the perforated expansion valve or orifice 6 and check valve 8, which prevents the pressure from rising inside the device and prevents contamination by impurities from the outside. , it can also prevent backflow.
本考案窒素製造装置は−190℃前後の低温下で
運転されるため、外部より侵入熱がある。又、熱
交換器の常温端における温度差（２〜３℃）があ
り、これが熱損失となる。このような熱損失に対
処するため本考案装置では、廃ガスに寒冷を付加
するため次の２種のいずれかの手段をとるもので
ある：
(1) 原料空気の一部を、熱交換器４の中間部から
取り出し、バイパス管路９′に設けた膨張ター
ビン９にて断熱膨張して冷却した後、熱交換器
４へ寒冷を供給する廃ガス管路１３に合流して
寒冷を付加する。または、
(2) 液体窒素、液体空気のような液化ガスを寒冷
源として管路１４から精留塔５又はコンデンサ
７に供給し、廃ガス管路１３から空気熱交換器
４に送られて常温まで温められ、この供給され
た液化ガスから常温のガスとなる熱量が付加寒
冷として利用される。 Since the nitrogen production equipment of the present invention is operated at a low temperature of around -190°C, there is heat intrusion from the outside. Additionally, there is a temperature difference (2 to 3° C.) at the normal temperature end of the heat exchanger, which results in heat loss. In order to cope with such heat loss, the device of the present invention takes one of the following two methods to add refrigeration to the waste gas: (1) A part of the raw air is transferred to a heat exchanger. 4, and is adiabatically expanded and cooled by the expansion turbine 9 provided in the bypass pipe 9', and then joins the waste gas pipe 13 that supplies cold to the heat exchanger 4 to add cold. . Or, (2) A liquefied gas such as liquid nitrogen or liquid air is supplied as a cold source to the rectification column 5 or the condenser 7 from the pipe 14, and the waste gas is sent to the air heat exchanger 4 from the waste gas pipe 13 and cooled to room temperature. The amount of heat from this supplied liquefied gas to room temperature gas is used as additional refrigeration.
上記の如き特徴的構成からなる本考案装置の窒
素発生プロセスを説明する。 The nitrogen generation process of the device of the present invention having the above-mentioned characteristic configuration will be explained.
空気圧縮機１で約１〜３Kg／cm2・ｇまで圧縮さ
れた原料空気は、空気冷却器２にて冷却され、切
替え可能のモレキユラー・シーブス塔３にて原料
空気中のCO2，H2Ｏ等の不純物を除去したのち
保冷槽２０に送られる。保冷槽２０内の空気熱交
換器４にて向流する製品窒素ガス及び廃ガスによ
つて液化点近くまで冷却された後窒素精留塔５に
送られる。 The raw air compressed to approximately 1 to 3 kg/cm 2 ·g by the air compressor 1 is cooled by the air cooler 2, and then converted to CO 2 and H 2 in the raw air by the switchable molecular sieves tower 3. After removing impurities such as O, it is sent to a cold storage tank 20. After being cooled to near the liquefaction point by the product nitrogen gas and waste gas flowing countercurrently in the air heat exchanger 4 in the cold storage tank 20, it is sent to the nitrogen rectification column 5.
窒素精留塔５においては塔頂で製品窒素が、塔
底で液体空気に精留分離される。塔底の液体空気
は内部に穴を有する膨張弁又はオリフイス６を備
えた管路１０を経て窒素コンデンサ７に送られ、
精留塔頂部の窒素により蒸発した後、廃ガスとし
て管路１３を経て前記熱交換器４を通り常温まで
加温された後、逆止弁８を備えた開放型の管路１
１より大気中に放出される。一方、塔頂の窒素の
一部は窒素コンデンサ７にて液化され、還流液と
して塔下部へゆき、残部は製品窒素として管路１
２を経て熱交換器４を通り常温まで加温された後
使用点へ送られる。 In the nitrogen rectification column 5, product nitrogen is separated by rectification at the top of the column and into liquid air at the bottom of the column. The liquid air at the bottom of the tower is sent to a nitrogen condenser 7 through a pipe 10 equipped with an expansion valve or orifice 6 having a hole inside.
After being evaporated by the nitrogen at the top of the rectification column, the waste gas is passed through the pipe 13, passed through the heat exchanger 4, and heated to room temperature.
1 is released into the atmosphere. On the other hand, a part of the nitrogen at the top of the tower is liquefied in the nitrogen condenser 7 and goes to the bottom of the tower as a reflux liquid, and the remainder is passed through the pipe line 1 as product nitrogen.
2 and a heat exchanger 4 where it is heated to room temperature and then sent to the point of use.
本考案装置は前述のとおり、コールドボツクス
内の流体ラインに仕切り個所を設けず、精留塔底
部と精留塔上部コンデンサとを連通する管路に内
部に穴を有する公知の膨張弁又はオリフイスを設
け、さらに廃ガス管路末端を逆止弁を設けて開放
型としてあるため、装置停止時等にも前記穴を有
する膨張弁又はオリフイス及び逆止弁を通つて精
留塔、コンデンサ等のガスが大気中に放出される
ので、コールドボツクス内部機器に異常な圧力が
かゝることを防止し得る顕著な効果を発揮し得
る。この効果は、原料空気の圧力が１〜３Kg／cm2
という低い圧力で運転される。本願考案の空気液
化精留による窒素製造装置では、特に有利であ
る。 As mentioned above, the device of the present invention does not provide a partition in the fluid line in the cold box, but instead uses a known expansion valve or orifice with an internal hole in the pipe line that communicates the bottom of the rectification column with the condenser at the top of the rectification column. Furthermore, since the end of the waste gas pipe is equipped with a check valve to make it open, even when the equipment is stopped, gas can be passed through the expansion valve or orifice with the hole and the check valve to the rectification column, condenser, etc. Since it is released into the atmosphere, it can have a remarkable effect of preventing abnormal pressure from being applied to the internal equipment of the cold box. This effect is due to the pressure of the raw air being 1 to 3 kg/cm 2
It is operated at low pressure. The nitrogen production apparatus using air liquefaction rectification according to the present invention is particularly advantageous.
添付図面は単式精留塔によつて窒素を製造する
本考案装置の一例を示すフローシートであり、
図中、１は空気圧縮機、２は空気冷却器、３は切
替式モレキユラー・シーブス塔、４は空気熱交換
器、５は窒素精留塔、６は穴明き膨張弁又はオリ
フイス、７は窒素コンデンサ、８は逆止弁、９は
膨張タービン、９′はバイパス管路、１０，１１，
１２，１３，１４はそれぞれ管路、２０は保冷
槽。
The attached drawing is a flow sheet showing an example of the device of the present invention for producing nitrogen using a single rectification column. In the drawing, 1 is an air compressor, 2 is an air cooler, 3 is a switching molecular sieve column, 4 is an air heat exchanger, 5 is a nitrogen rectification column, 6 is a perforated expansion valve or orifice, 7 is a nitrogen condenser, 8 is a check valve, 9 is an expansion turbine, 9' is a bypass pipe, 10, 11 ，
12, 13, and 14 are conduits, respectively, and 20 is a cold storage tank.
Claims (1)
精製器、製品ガス及び廃ガスと熱交換して原料
空気を液化点まで冷却する熱交換器、冷却され
た空気を精留する精留塔、精留塔頂部から製品
窒素を取出す管路、精留塔上部のコンデンサか
ら廃ガスを取出す管路、熱交換器に送られる廃
ガスに寒冷を付加する手段を含む窒素製造装置
において、精留塔５底部と該精留塔上部コンデ
ンサ７とを連通する管路１０に、内部に穴を有
する膨張弁か又はオリフイス６を設け、かつ逆
止弁８を有する廃ガス管路１１を大気開放型と
した窒素製造装置。 (2) 前記廃ガスに寒冷を付加する手段が、熱交換
器４の中間部から原料空気の一部を取出し前記
コンデンサ７からの廃ガス取出し管路１３に連
通する膨張タービン９を具備するバイパス管路
９′である実用新案登録請求の範囲第１項記載
の窒素製造装置。 (3) 前記廃ガスに寒冷を付加する手段が、精留塔
５又はコンデンサ７に外部から液体窒素又は液
体空気を供給する管路１４を設けることである
実用新案登録請求の範囲第１項記載の窒素製造
装置。[Scope of claims for utility model registration] (1) A compressor that compresses raw air to 1 to 3 kg/cm 2 ;
Purifier, heat exchanger that cools the feed air to the liquefaction point by exchanging heat with the product gas and waste gas, a rectifier that rectifies the cooled air, a pipe line that extracts product nitrogen from the top of the rectifier, and a rectifier that cools the feed air to the liquefaction point. In a nitrogen production device that includes a pipe line for extracting waste gas from a condenser at the top of the distillation column, and a means for adding refrigeration to the waste gas sent to a heat exchanger, the bottom of the rectification column 5 is connected to the condenser 7 at the top of the rectification column. A nitrogen production device in which an expansion valve or an orifice 6 having a hole inside is provided in a pipe 10 in which a waste gas pipe 11 having a check valve 8 is opened to the atmosphere. (2) A bypass in which the means for adding refrigeration to the waste gas includes an expansion turbine 9 that extracts a part of the raw air from the intermediate portion of the heat exchanger 4 and communicates with the waste gas extraction pipe 13 from the condenser 7. The nitrogen production apparatus according to claim 1, which is a pipe 9'. (3) The utility model registration claimed in claim 1, wherein the means for adding refrigeration to the waste gas is to provide a pipe line 14 for supplying liquid nitrogen or liquid air from the outside to the rectification column 5 or condenser 7. Nitrogen production equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10450484U JPS6121291U (en) | 1984-07-12 | 1984-07-12 | Nitrogen production equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10450484U JPS6121291U (en) | 1984-07-12 | 1984-07-12 | Nitrogen production equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6121291U JPS6121291U (en) | 1986-02-07 |
| JPH0434391Y2 true JPH0434391Y2 (en) | 1992-08-17 |
Family
ID=30663852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10450484U Granted JPS6121291U (en) | 1984-07-12 | 1984-07-12 | Nitrogen production equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6121291U (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5241232A (en) * | 1975-09-24 | 1977-03-30 | Bayer Ag | Weed killer |
| JPS5412690A (en) * | 1977-06-30 | 1979-01-30 | Matsushita Electric Works Ltd | Photoelectric switch |
-
1984
- 1984-07-12 JP JP10450484U patent/JPS6121291U/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5241232A (en) * | 1975-09-24 | 1977-03-30 | Bayer Ag | Weed killer |
| JPS5412690A (en) * | 1977-06-30 | 1979-01-30 | Matsushita Electric Works Ltd | Photoelectric switch |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6121291U (en) | 1986-02-07 |
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