JPH05180559A - Air liquefaction/separation method - Google Patents

Air liquefaction/separation method

Info

Publication number
JPH05180559A
JPH05180559A JP17057792A JP17057792A JPH05180559A JP H05180559 A JPH05180559 A JP H05180559A JP 17057792 A JP17057792 A JP 17057792A JP 17057792 A JP17057792 A JP 17057792A JP H05180559 A JPH05180559 A JP H05180559A
Authority
JP
Japan
Prior art keywords
rectification column
nitrogen
column
hydrogen
auxiliary
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.)
Granted
Application number
JP17057792A
Other languages
Japanese (ja)
Other versions
JP2553989B2 (en
Inventor
Takashi Tatsumi
▲高▼司 辰巳
Hideyuki Honda
秀幸 本田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Japan Oxygen Co Ltd
Nippon Sanso Corp
Original Assignee
Japan Oxygen Co Ltd
Nippon Sanso Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Japan Oxygen Co Ltd, Nippon Sanso Corp filed Critical Japan Oxygen Co Ltd
Priority to JP4170577A priority Critical patent/JP2553989B2/en
Publication of JPH05180559A publication Critical patent/JPH05180559A/en
Application granted granted Critical
Publication of JP2553989B2 publication Critical patent/JP2553989B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04763—Start-up or control of the process; Details of the apparatus used
    • F25J3/04866—Construction and layout of air fractionation equipments, e.g. valves, machines
    • F25J3/04872—Vertical layout of cold equipments within in the cold box, e.g. columns, heat exchangers etc.
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04406—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system
    • F25J3/04412—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system in a classical double column flowsheet, i.e. with thermal coupling by a main reboiler-condenser in the bottom of low pressure respectively top of high pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04406—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system
    • F25J3/0443—A main column system not otherwise provided, e.g. a modified double column flowsheet
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04436—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using at least a triple pressure main column system
    • F25J3/04448—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using at least a triple pressure main column system in a double column flowsheet with an intermediate pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/32—Processes or apparatus using separation by rectification using a side column fed by a stream from the high pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2215/00—Processes characterised by the type or other details of the product stream
    • F25J2215/42—Nitrogen or special cases, e.g. multiple or low purity N2
    • F25J2215/44—Ultra high purity nitrogen, i.e. generally less than 1 ppb impurities
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2220/00—Processes or apparatus involving steps for the removal of impurities
    • F25J2220/42—Separating low boiling, i.e. more volatile components from nitrogen, e.g. He, H2, Ne
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/20—Boiler-condenser with multiple exchanger cores in parallel or with multiple re-boiling or condensing streams

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Separation By Low-Temperature Treatments (AREA)

Abstract

PURPOSE:To effectively, simply and inexpensively reduce and remove low boiling point components such as hydrogen in article nitrogen in an air liquefaction/ separation method. CONSTITUTION:An auxiliary rectification tower 30 is provided on a main rectification tower 2, and nitrogen gas from the main rectification tower 2 is introduced as ascending gas into a lower part of the auxiliary rectification tower 30 while being adjusted in its amount. Further, liquefied nitrogen from the main rectification tower 2 is liquefied and introduced as a reflux fluid into the auxiliary rectification tower 30 for rectification while being adjusted in its amount. Further, there is derived nitrogen gas including more amounts of low boiling point components such as hydrogen from the top of the auxiliary rectification tower 30. Additionally, there is derived high purification liquefied nitrogen of 1ppm or less contents of the low boiling point components such as hydrogen from the bottom of the auxiliary rectification tower 30.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、原料空気より混入する
水素等低沸点成分の含有量を低減した高純度窒素を採取
する空気液化分離方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air liquefaction separation method for collecting high-purity nitrogen with a reduced content of low-boiling components such as hydrogen mixed from raw material air.

【０００２】[0002]

【従来の技術】工業的に窒素を製造する方法として、空
気を原料としてこれを液化し、その組成分を精留塔を用
いてその沸点差によって分離するいわゆる空気液化分離
方法が採用されている。2. Description of the Related Art As a method for industrially producing nitrogen, a so-called air liquefaction separation method has been adopted in which air is used as a raw material and is liquefied, and its composition is separated by a boiling point difference using a rectification column. ..

【０００３】従来の空気液化分離方法を単式精留塔と複
式精留塔に分けて説明する。単式精留塔の場合は、例え
ば図７に示す如く、塵埃，炭酸ガス及び水分を除去され
た圧縮精製原料空気が径路１を通って単式精留塔２の下
部に導入され、単式精留塔２内で上部より精留板３を流
下する還流液によって精留され、単式精留塔２上部に窒
素ガスを、底部に酸素に富んだ液化空気を夫々生成す
る。The conventional air liquefaction separation method will be described separately for a single type rectification column and a double type rectification column. In the case of a single-column rectification column, for example, as shown in FIG. 7, compressed and purified raw material air from which dust, carbon dioxide gas and water have been removed is introduced into the lower part of the single-column rectification column 2 through a path 1. The gas is rectified by the reflux liquid flowing down the rectification plate 3 from the upper part in the column 2, and nitrogen gas is generated in the upper part of the single-column rectification column 2 and liquefied air rich in oxygen is generated in the lower part.

【０００４】生成された前記窒素ガスは、単式精留塔２
上部から径路４を通ってその一部が製品窒素ガスとして
導出され、残部が径路５を通って単式精留塔２直上に区
画された凝縮蒸発器６に導入され、単式精留塔２底部か
ら径路７を通って凝縮蒸発器６に導入される液化空気と
熱交換して液化窒素となり、径路８を通って単式精留塔
２の上部に導入されて還流液となる。The generated nitrogen gas is used in the single-column rectification column 2
A part of it is discharged as product nitrogen gas from the upper part through the path 4, and the remaining part is introduced through the path 5 into the condenser / evaporator 6 which is partitioned directly above the single-column rectification column 2, and from the bottom of the single-column rectification column 2. Liquefied air is heat-exchanged with the liquefied air introduced into the condensation evaporator 6 through the path 7 and becomes liquefied nitrogen, and is introduced into the upper part of the single-column rectification column 2 through the path 8 and becomes the reflux liquid.

【０００５】複式精留塔の場合は、例えば図８に示す如
く、単式精留塔２の場合と略同様に径路１０から複式精
留塔の下部塔１１に導入された原料空気が還流液との間
で精留され、下部塔１１上部に窒素ガスを、下部塔１１
底部に液化空気を夫々生成する。下部塔１１上部に生成
した前記窒素ガスは、径路１２を通って主凝縮蒸発器１
３に入り、液化酸素等と熱交換して液化窒素となり、一
部は径路１４を通って下部塔１１上部に還流液として戻
されると共に、残部は径路１５を通り過冷器１６及び膨
張弁１７を通って膨張降圧し、上部塔１８頂部に導入さ
れて還流液となる。In the case of the double rectification column, for example, as shown in FIG. 8, the raw material air introduced from the path 10 to the lower column 11 of the double rectification column is used as the reflux liquid in the same manner as in the case of the single rectification column 2. Between the lower tower 11 and the nitrogen gas above the lower tower 11
Liquefied air is generated at the bottom. The nitrogen gas generated in the upper part of the lower tower 11 passes through the path 12 and the main condenser evaporator 1
3, and exchanges heat with liquefied oxygen and the like to become liquefied nitrogen, part of which is returned to the upper part of the lower column 11 as reflux liquid through the path 14, and the rest passes through the path 15 and the subcooler 16 and the expansion valve 17 It is expanded and depressurized through and is introduced into the top of the upper tower 18 to form a reflux liquid.

【０００６】一方、下部塔１１下部からは原料空気の一
部が径路１９を通って膨張タービン２０で膨張されて上
部塔１８の中部に導入され、この空気および上部塔１８
下部に導入される主凝縮蒸発器１３からの蒸発ガス（図
示せず）と、下部塔１１底部から径路２１，過冷器２２
及び膨張弁２３を経て上部塔１８の中上部に導入される
液化空気および前記還流液の間で本精留が行なわれ、上
部塔１８上部に窒素ガスが生成される。この窒素ガス
は、径路２４を通って製品窒素ガスとして導出され、上
部塔１８底部からは径路２５を通って酸素ガスまたは液
化酸素が導出される。On the other hand, part of the raw material air from the lower part of the lower tower 11 is expanded by the expansion turbine 20 through the path 19 and introduced into the middle part of the upper tower 18, and this air and the upper tower 18 are supplied.
Evaporated gas (not shown) from the main condenser evaporator 13 introduced into the lower part, the path 21 from the bottom part of the lower tower 11 and the supercooler 22
Further, the main rectification is performed between the liquefied air and the reflux liquid introduced into the upper part of the upper tower 18 through the expansion valve 23, and nitrogen gas is generated in the upper part of the upper tower 18. This nitrogen gas is discharged as product nitrogen gas through the path 24, and oxygen gas or liquefied oxygen is discharged from the bottom of the upper tower 18 through the path 25.

【０００７】[0007]

【発明が解決しようとする課題】しかし、このようにし
て生成される製品窒素ガス中には、原料空気の中に微量
に含まれていた水素等の低沸点成分が濃縮されて含まれ
る。即ち、製品窒素ガス中には、一般に２〜１０ｐｐｍ
の水素，８〜２０ｐｐｍのヘリウム，４０〜１００ｐｐ
ｍのネオンが含有されている。そして、これらの成分
は、たとえ微量であっても半導体工業等の超高純度の窒
素ガスを要求している分野においては、その製品に及ぼ
す影響が大きく改善が要求されていた。However, the product nitrogen gas thus produced contains a low-boiling-point component such as hydrogen, which was contained in a trace amount in the raw material air, in a concentrated manner. That is, in product nitrogen gas, generally 2 to 10 ppm
Hydrogen, 8-20ppm helium, 40-100pp
m neon is contained. In addition, even in a small amount, these components are required to be greatly improved in their influence on the products in the fields requiring ultra-high purity nitrogen gas such as semiconductor industry.

【０００８】本発明の目的は、上記の点に鑑みなされた
もので、製品窒素中の水素等の低沸点成分を効率よく簡
単かつ廉価に低減除去する空気液化分離方法を提供する
ことにある。An object of the present invention is to provide an air liquefaction separation method which has been made in view of the above points and which efficiently and easily removes low boiling point components such as hydrogen in product nitrogen at low cost.

【０００９】[0009]

【課題を解決するための手段】上記の目的を達成するた
め、第１発明は、高純度窒素を採取する空気液化分離方
法において、主精留塔に補助精留塔を付設し、該補助精
留塔の下部に主精留塔よりの窒素ガスをその量を調節し
つつ導入して上昇ガスとし、主精留塔より導出した液化
窒素または窒素ガスを液化して前記補助精留塔に還流液
として、その量を調節しつつ導入して精留を行なわせ、
該補助精留塔頂部より水素等低沸点成分の含有量の多く
なった窒素ガスを導出すると共に、該補助精留塔底部よ
り水素等低沸点成分の含有量１ｐｐｍ以下の高純度液化
窒素を導出することを特徴とするものである。In order to achieve the above object, the first invention is an air liquefaction separation method for collecting high-purity nitrogen, wherein an auxiliary rectification column is attached to the main rectification column, and the auxiliary rectification column is attached. Nitrogen gas from the main rectification column is introduced into the lower part of the distillation column while adjusting its amount to make an ascending gas, and liquefied nitrogen or nitrogen gas derived from the main rectification column is liquefied and refluxed to the auxiliary rectification column. As a liquid, while adjusting the amount, it is introduced and rectification is performed,
Nitrogen gas having a high content of low boiling point components such as hydrogen is discharged from the top of the auxiliary rectification column, and high-purity liquefied nitrogen having a content of low boiling point components such as hydrogen of 1 ppm or less is discharged from the bottom of the auxiliary rectification column. It is characterized by doing.

【００１０】また第２発明は、第１発明において、補助
精留塔底部より導出した水素等低沸点成分の含有量１ｐ
ｐｍ以下の高純度液化窒素の一部を凝縮蒸発器を経て気
化して水素等低沸点成分の含有量１ｐｐｍ以下の高純度
窒素ガスとして導出することを特徴とするものである。The second invention is the same as the first invention, wherein the content of the low boiling point component such as hydrogen derived from the bottom of the auxiliary rectification column is 1 p.
Part of high-purity liquefied nitrogen of pm or less is vaporized through a condensing evaporator to be discharged as high-purity nitrogen gas having a low boiling point component such as hydrogen of 1 ppm or less.

【００１１】[0011]

【実施例】以下本発明の実施例について図面に基づいて
説明する。なお、図７および図８と同一構成要素につい
ては、同符号を付してその詳細な説明は省略する。Embodiments of the present invention will be described below with reference to the drawings. The same components as those in FIGS. 7 and 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

【００１２】図１は、本発明を単式精留塔に適用した第
１実施例を示すもので、単式精留塔２に補助精留塔３０
を設けた場合である。単式精留塔２上部より導出した窒
素ガスの一部を、径路３１の調節弁３２でその量を調節
しつつ前記補助精留塔３０の下部に導入して上昇ガスと
し、単式精留塔２上部の残りの窒素ガスを径路５を介し
て凝縮蒸発器６の凝縮側に導入し、径路７から凝縮蒸発
器６に導入された液化空気および補助精留塔３０の底部
から径路３３を通って凝縮蒸発器６の蒸発側に導入され
た液化窒素により液化し、径路８に導出した液化窒素の
一部を分岐して径路３４の膨張弁３５で膨張降圧し、前
記補助精留塔３０の上部に還流液として、その量を調節
しつつ導入し精留を行なわせる。FIG. 1 shows a first embodiment in which the present invention is applied to a single-column rectification column. A single-column rectification column 2 and an auxiliary rectification column 30 are shown.
Is provided. A part of the nitrogen gas derived from the upper part of the single-column rectification column 2 is introduced into the lower part of the auxiliary rectification column 30 while adjusting the amount thereof by the control valve 32 of the path 31, and is made into ascending gas. The remaining nitrogen gas in the upper part is introduced into the condensation side of the condensation evaporator 6 via the path 5, and the liquefied air introduced into the condensation evaporator 6 from the path 7 and the bottom of the auxiliary rectification column 30 are passed through the path 33. The liquefied nitrogen introduced to the evaporation side of the condenser-evaporator 6 is liquefied, a part of the liquefied nitrogen discharged to the path 8 is branched, and the expansion valve 35 of the path 34 expands and lowers the pressure, and the upper part of the auxiliary rectification column 30. As a reflux liquid, it is introduced while controlling its amount to carry out rectification.

【００１３】そして、補助精留塔３０頂部より水素等低
沸点成分の含有量の多くなった窒素ガスを、径路３６の
調節弁３７で濃度を制御しながら導出し、一方、補助精
留塔３０底部より水素等低沸点成分の含有量１ｐｐｍ以
下の高純度液化窒素を径路３８より導出すると共に、こ
の高純度液化窒素の一部を前記径路３３を通して凝縮蒸
発器６の蒸発側に導入して気化させ、径路３９から水素
等低沸点成分の含有量１ｐｐｍ以下の高純度窒素ガスを
導出する。また、径路８で一部を分岐した液化窒素の残
部は、径路４０により単式精留塔２の上部に還流液とし
て戻される。Nitrogen gas, which has a high content of low boiling point components such as hydrogen, is discharged from the top of the auxiliary rectification column 30 while controlling the concentration thereof with a control valve 37 of a path 36, while the auxiliary rectification column 30 is discharged. High-purity liquefied nitrogen containing 1 ppm or less of low-boiling-point components such as hydrogen from the bottom is led out from the path 38, and a part of this high-purity liquefied nitrogen is introduced into the evaporation side of the condensation evaporator 6 through the path 33 and vaporized. Then, the high-purity nitrogen gas having a content of the low boiling point component such as hydrogen of 1 ppm or less is discharged from the path 39. Further, the remaining part of the liquefied nitrogen which is partially branched in the path 8 is returned to the upper portion of the single-column rectification column 2 as a reflux liquid by the path 40.

【００１４】このように、単精留塔２に補助精留塔３０
を付設し、補助精留塔３０の下部に上昇ガスとして導入
される窒素ガスおよび補助精留塔３０の上部に還流液と
して導入される液化窒素の量を、調節弁３２，膨張弁３
５で調節して精留することにより、補助精留塔３０底部
より水素等低沸点成分の含有量１ｐｐｍ以下の高純度液
化窒素を得ることができる。即ち、補助精留塔３０の上
部における水素等低沸点成分の濃縮の程度は、調節弁３
２，膨張弁３５により調節される径路３１，３４の窒素
量に支配され、径路３３，３８より導出される液化窒素
中の水素等低沸点成分の量も、調節弁３２，膨張弁３
５，調節弁３７等の調節により１ｐｐｍ以下にすること
ができる。Thus, the auxiliary rectification column 30 is added to the single rectification column 2.
Is attached, and the amount of nitrogen gas introduced as a rising gas to the lower part of the auxiliary rectification column 30 and the amount of liquefied nitrogen introduced to the upper part of the auxiliary rectification column 30 as a reflux liquid are controlled by the control valve 32 and the expansion valve 3.
By adjusting with 5 and rectifying, high-purity liquefied nitrogen containing 1 ppm or less of low boiling point components such as hydrogen can be obtained from the bottom of the auxiliary rectification column 30. That is, the degree of concentration of low boiling point components such as hydrogen in the upper part of the auxiliary rectification column 30 is controlled by the control valve 3
2. The amount of low boiling point components such as hydrogen in the liquefied nitrogen, which is controlled by the amount of nitrogen in the paths 31 and 34 adjusted by the expansion valve 35 and is derived from the paths 33 and 38, is also controlled by the control valve 32 and the expansion valve 3.
5. It can be reduced to 1 ppm or less by adjusting the control valve 37 or the like.

【００１５】また、この水素等低沸点成分の含有量１ｐ
ｐｍ以下の高純度液化窒素の一部を凝縮蒸発器６で気化
させることにより、水素等低沸点成分の含有量１ｐｐｍ
以下の高純度窒素ガスも得られる。The content of this low boiling point component such as hydrogen is 1 p
By vaporizing part of high-purity liquefied nitrogen of pm or less in the condensation evaporator 6, the content of low boiling point components such as hydrogen is 1 ppm.
The following high-purity nitrogen gas can also be obtained.

【００１６】図２は第２実施例を示すもので、複式精留
塔の上部塔１８の上方に補助精留塔４０を設けた場合で
ある。上部塔１８頂部より径路２４を通って導出される
製品窒素ガスの一部を、径路４１の調節弁４２でその量
を調節しつつ前記補助精留塔４０の下部に導入して上昇
ガスとし、複式精留塔の前記下部塔１１（図８図示）頂
部より導出した液化窒素または下部塔１１上部より導出
した窒素ガスを主凝縮蒸発器１３に導入して液化窒素と
したものを径路１５の膨張弁１７を介して膨張降圧し、
還流液として前記補助精留塔４０上部に導入して精留を
行なわせる。FIG. 2 shows a second embodiment in which an auxiliary rectification column 40 is provided above the upper column 18 of the double rectification column. A part of the product nitrogen gas discharged from the top of the upper tower 18 through the path 24 is introduced into the lower portion of the auxiliary rectification tower 40 while adjusting the amount thereof by the control valve 42 of the path 41, and is used as the rising gas, The liquefied nitrogen derived from the top of the lower column 11 (shown in FIG. 8) of the double-column rectification column or the nitrogen gas derived from the upper part of the lower column 11 is introduced into the main condenser evaporator 13 to be liquefied nitrogen, which is expanded in the path 15. Inflation and depressurization via valve 17,
As a reflux liquid, it is introduced into the upper part of the auxiliary rectification column 40 to carry out rectification.

【００１７】そして、該補助精留塔４０頂部より水素等
低沸点成分の含有量の多くなった窒素ガスを、径路４３
の調節弁４４で濃度を制御しながら導出し、一方、該補
助精留塔４０底部より水素等低沸点成分の含有量１ｐｐ
ｍ以下の高純度液化窒素を径路４５を通して導出する。
また、この高純度液化窒素の一部を径路４６を通して、
上部塔１８頂部に還流液として導入する。Then, the nitrogen gas containing a large amount of low-boiling components such as hydrogen from the top of the auxiliary rectification column 40 is passed through the path 43.
The concentration of the low boiling point component such as hydrogen is 1 pp from the bottom of the auxiliary rectification column 40.
High-purity liquefied nitrogen of m or less is led out through the path 45.
In addition, a portion of this high-purity liquefied nitrogen is passed through the path 46,
It is introduced as a reflux liquid at the top of the upper tower 18.

【００１８】このように、主凝縮蒸発器１３で生じた低
沸点成分を多く含む液化窒素を上部塔１８に導入する前
に補助精留塔４０に導入して予備的に精留することによ
り、径路４５より得られる高純度液化窒素中の水素等低
沸点成分を１ｐｐｍ以下にすることができる。この濃度
の調節は、前記調節弁４２、膨張弁１７で補助精留塔４
０に導入する窒素ガスや液化窒素の量を調節することお
よび調節弁４４で径路４３より導出する排窒素ガスの量
を調節することにより行なうことができる。In this way, by introducing the liquefied nitrogen containing a large amount of low boiling point components generated in the main condenser evaporator 13 into the auxiliary rectification column 40 and preliminarily rectifying it before introducing it into the upper column 18. The low boiling point component such as hydrogen in the high-purity liquefied nitrogen obtained from the path 45 can be reduced to 1 ppm or less. The concentration is adjusted by using the control valve 42 and the expansion valve 17 for the auxiliary rectification column 4
This can be performed by adjusting the amounts of nitrogen gas and liquefied nitrogen introduced to 0 and adjusting the amount of exhaust nitrogen gas discharged from the path 43 by the control valve 44.

【００１９】また、水素等低沸点成分の含有量１ｐｐｍ
以下の高純度液化窒素の一部を、径路４６を通して上部
塔１８頂部に還流液として導入し、上部塔１８上部に上
昇してくる窒素ガスとの間で精留を行わせることによ
り、上部塔１８上部から径路２４を介して低沸点成分の
含有量の少ない高純度窒素ガスを取出すこともできる。The content of low boiling point components such as hydrogen is 1 ppm
A part of the following high-purity liquefied nitrogen is introduced as a reflux liquid to the top of the upper tower 18 through the path 46, and rectification is carried out with the nitrogen gas rising to the upper part of the upper tower 18 to obtain the upper tower. It is also possible to take out high-purity nitrogen gas having a low content of low-boiling components from the upper part of 18 via the path 24.

【００２０】図３は本発明の第３実施例を示すもので、
複式精留塔の上部塔１８の圧力より少し高い圧力状態中
に補助精留塔５０を設けた場合である。複式精留塔の下
部塔１１頂部より導出した窒素ガスの一部を、径路５１
の調節弁５２でその量を調節しつつ補助精留塔５０の下
部に導入して上昇ガスとし、下部塔１１頂部より導出し
た窒素ガスの残部を径路１２を介して主凝縮蒸発器１３
で液化酸素等により液化し、この液化窒素の一部を径路
１５の過冷器１６で冷却した後膨張弁１７で膨張降圧さ
せ、低沸点成分が濃縮されたフラッシュガスを含む液化
窒素として前記補助精留塔５０頂部に還流液として導入
し精留を行なわせる。FIG. 3 shows a third embodiment of the present invention.
This is a case where the auxiliary rectification column 50 is provided in a pressure state slightly higher than the pressure of the upper column 18 of the double rectification column. A part of the nitrogen gas derived from the top of the lower column 11 of the double-column rectification column was passed through the path 51.
The amount of the nitrogen gas is introduced into the lower part of the auxiliary rectification column 50 as an ascending gas while the amount is adjusted by a control valve 52 of the above, and the remaining nitrogen gas derived from the top of the lower part column 11 is passed through the path 12 to the main condenser evaporator 13
Is liquefied by liquefied oxygen, etc., and a part of this liquefied nitrogen is cooled in the subcooler 16 of the path 15 and then expanded and reduced in pressure by the expansion valve 17 to serve as liquefied nitrogen containing flash gas in which low boiling point components are concentrated. It is introduced as a reflux liquid at the top of the rectification column 50 to carry out rectification.

【００２１】そして、補助精留塔５０頂部より水素等低
沸点成分の含有量の多くなった前記フラッシュガスを含
む窒素ガスを、径路５３の調節弁５４で水素等低沸点成
分の濃度を制御して導出すると共に、該補助精留塔５０
底部より水素等低沸点成分の含有量１ｐｐｍ以下の高純
度液化窒素を径路５５より導出する。また、この高純度
液化窒素の一部を径路５６の弁５７でその量を調節して
複式精留塔の上部塔１８頂部に還流液として導入し、上
部塔１８内を上昇する窒素ガスとさらに精留を行なわせ
ることにより、上部塔１８頂部より径路２４を通して水
素等低沸点成分の含有量の少ない高純度窒素ガスを導出
することができる。The nitrogen gas containing the above-mentioned flash gas having a higher content of low boiling point components such as hydrogen from the top of the auxiliary rectification column 50 is controlled by the control valve 54 in the path 53 to control the concentration of low boiling point components such as hydrogen. And the auxiliary rectification tower 50
High-purity liquefied nitrogen containing 1 ppm or less of a low boiling point component such as hydrogen is led out from the bottom through a path 55. In addition, a part of this high-purity liquefied nitrogen is introduced as a reflux liquid into the top of the upper column 18 of the double rectification column by adjusting the amount thereof with the valve 57 of the path 56, and the nitrogen gas rising in the upper column 18 and further By carrying out the rectification, high-purity nitrogen gas having a low content of low boiling point components such as hydrogen can be discharged from the top of the upper column 18 through the path 24.

【００２２】なお、径路５５，５７より導出する液化窒
素中の水素等低沸点成分の含有量が１ｐｐｍ以下になる
ように膨脹弁１７，調節弁５２を調節して、径路１５，
５１の窒素量を制御する。この場合、膨脹弁１７、調節
弁５２は手動であり、調節弁５４はこれに伴う系内の圧
力を検出して作動する自動圧力調節弁である。The expansion valve 17 and the control valve 52 are adjusted so that the content of the low boiling point component such as hydrogen in the liquefied nitrogen discharged from the paths 55 and 57 is 1 ppm or less.
Control the nitrogen content of 51. In this case, the expansion valve 17 and the control valve 52 are manual, and the control valve 54 is an automatic pressure control valve that operates by detecting the pressure in the system accompanying this.

【００２３】また、一体型の複式精留塔で直管型の主凝
縮蒸発器を使用の場合は、下部塔頂部に溜った液化窒素
の一部を前記補助精留塔５０頂部に還流液として導入す
る。When a straight tube type main condenser evaporator is used in the integrated double rectification column, a part of the liquefied nitrogen accumulated at the top of the lower column is used as a reflux liquid at the top of the auxiliary rectification column 50. Introduce.

【００２４】図４は本発明の第４実施例を示すもので、
複式精留塔の下部塔１１の圧力より少し低い圧力状態中
に補助精留塔６０を設けた場合である。図３で説明した
第３実施例と同様に、補助精留塔６０の下部に下部塔１
１頂部より導出した窒素ガスの一部を、径路６１の調節
弁６２でその量を調節しつつ導入して上昇ガスとし、残
りの窒素ガスを径路１２，主凝縮蒸発器１３を介して液
化窒素とし、その一部を径路１５の調節弁６３を介して
前記補助精留塔６０上部へ還流液として導入し精留を行
なわせる。FIG. 4 shows a fourth embodiment of the present invention.
This is a case where the auxiliary rectification column 60 is provided in a pressure state slightly lower than the pressure of the lower column 11 of the double rectification column. Similar to the third embodiment described with reference to FIG. 3, the lower tower 1 is provided at the bottom of the auxiliary rectification tower 60.
1 A part of the nitrogen gas derived from the top is introduced while adjusting its amount with a control valve 62 of a path 61 to be an ascending gas, and the remaining nitrogen gas is liquefied nitrogen via a path 12 and a main condenser evaporator 13. Then, a part thereof is introduced as a reflux liquid into the upper portion of the auxiliary rectification column 60 through the control valve 63 of the path 15 to carry out rectification.

【００２５】そして、補助精留塔６０頂部より水素等低
沸点成分の濃度を制御する調節弁６４を設けた径路６５
を通して水素等低沸点成分の含有量の多い窒素ガスを導
出すると共に、補助精留塔６０底部より水素等低沸点成
分の含有量１ｐｐｍ以下の高純度液化窒素を径路６６か
ら導出する。また、この高純度液化窒素の一部を経路６
７に分岐して過冷器１６及び膨張弁１７を通して過冷及
び膨張降圧し、上部塔１８頂部に還流液として導入し、
該上部塔１８内を上昇する窒素ガスとさらに精留を行な
わせ、上部塔１８頂部より径路２４を通して水素等低沸
点成分の含有量の少ない高純度窒素ガスを導出する。A path 65 provided with a control valve 64 for controlling the concentration of low boiling point components such as hydrogen from the top of the auxiliary rectification column 60.
A nitrogen gas having a high content of low boiling point components such as hydrogen is discharged through the same, and high-purity liquefied nitrogen having a content of low boiling point components such as hydrogen of 1 ppm or less is discharged from the bottom of the auxiliary rectification column 60 through the path 66. In addition, part of this high-purity liquefied nitrogen is passed through the route 6
7 to be supercooled and expanded and reduced in pressure through a subcooler 16 and an expansion valve 17, and introduced as a reflux liquid to the top of the upper tower 18,
Nitrogen gas rising in the upper column 18 is further rectified, and high-purity nitrogen gas containing a small amount of low boiling point components such as hydrogen is discharged from the top of the upper column 18 through a path 24.

【００２６】なお、径路６６より導出する液化窒素中の
水素等低沸点成分の含有量が１ｐｐｍ以下になるよう
に、調節弁６２，６３を調節して径路１５，６１の窒素
量を制御する。The control valves 62 and 63 are adjusted so that the content of the low boiling point component such as hydrogen in the liquefied nitrogen discharged from the path 66 is 1 ppm or less, and the amount of nitrogen in the paths 15 and 61 is controlled.

【００２７】また、一体型の複式精留塔で直管型の主凝
縮蒸発器を使用の場合は、この実施例の場合にも、下部
塔１１頂部に溜った液化窒素の一部を補助精留塔６０頂
部に還流液として導入する。Further, in the case of using the straight tube type main condenser evaporator in the integrated double rectification column, also in this embodiment, a part of the liquefied nitrogen accumulated at the top of the lower column 11 is supplementarily purified. It is introduced as a reflux liquid at the top of the distillation column 60.

【００２８】次に、図８に示す従来方法の場合と、図３
に示す本発明の第３実施例及び図４に示す本発明の第４
実施例について、その各部位の流量及び水素濃度を表１
及び表２に示す。なお、表１の部位（ａ〜ｐ）を図５
に、表２の部位（ｆ′〜ｏ′）を図６に示す。Next, in the case of the conventional method shown in FIG.
Embodiment 3 of the present invention shown in FIG. 4 and Embodiment 4 of the present invention shown in FIG.
Table 1 shows the flow rate and hydrogen concentration of each part of the example.
And shown in Table 2. The parts (a to p) in Table 1 are shown in FIG.
FIG. 6 shows the sites (f ′ to o ′) in Table 2.

【００２９】[0029]

【表１】 [Table 1]

【００３０】[0030]

【表２】 [Table 2]

【００３１】この計算結果から明らかなように、１９０
００Ｎｍ3 ／ｈの原料空気を導入して１５００Ｎｍ3 ／
ｈの製品窒素ガスを取出す場合、従来は、１０．２ｐｐ
ｍの水素成分が製品窒素ガス中に含有されていたもの
が、本第３実施例では補助精留塔の操作圧力を１．５at
a ，２．０ata にし、理論段数を夫々１．５段，２段と
したとき、０．２ｐｐｍにまで低減除去することがで、
本第４実施例では補助精留塔の操作圧力を５．５ata に
し、理論段数を３段としたとき、０．３ｐｐｍにまで低
減除去することができる。As is clear from this calculation result, 190
00Nm 3 / h by introducing the feed air of 1500Nm 3 /
When taking out the product nitrogen gas of h, it was 10.2pp in the past.
Although the hydrogen component of m was contained in the product nitrogen gas, the operating pressure of the auxiliary rectification column was 1.5 at in the third embodiment.
a and 2.0 ata and theoretical plate numbers of 1.5 and 2, respectively, it is possible to reduce and remove to 0.2 ppm.
In the fourth embodiment, when the operating pressure of the auxiliary rectification column is set to 5.5ata and the number of theoretical plates is set to 3, the removal amount can be reduced to 0.3 ppm.

【００３２】なお、理論段数は理想塔のもので、実際の
塔では、気液接触の不完全や飛沫同伴などが生じ、理想
塔よりも多数の段数を必要とする。The theoretical number of plates is that of an ideal column. In an actual column, incomplete gas-liquid contact and entrainment of droplets occur, and thus a larger number of plates than the ideal column is required.

【００３３】[0033]

【発明の効果】本発明は以上説明した如く、主精留塔に
補助精留塔を付設し、該補助精留塔の下部に主精留塔よ
りの窒素ガスをその量を調節しつつ導入して上昇ガスと
し、主精留塔より導出した液化窒素または窒素ガスを液
化して前記補助精留塔に還流液として、その量を調節し
つつ導入して精留を行なわせ、該補助精留塔頂部より水
素等低沸点成分の含有量の多くなった窒素ガスを導出す
ると共に、該補助精留塔底部より水素等低沸点成分の含
有量１ｐｐｍ以下の高純度液化窒素を導出するので、水
素等の低沸点成分を効率よく簡単かつ廉価に低減するこ
とができ、高純度液化窒素を容易に製造することができ
る。INDUSTRIAL APPLICABILITY As described above, according to the present invention, an auxiliary rectification column is attached to the main rectification column, and nitrogen gas from the main rectification column is introduced into the lower part of the auxiliary rectification column while controlling its amount. As a rising gas, and liquefied liquefied nitrogen or nitrogen gas derived from the main rectification column is liquefied to the auxiliary rectification column as a reflux liquid, which is introduced while controlling its amount to carry out rectification. Since nitrogen gas having a high content of low boiling point components such as hydrogen is discharged from the top of the distillation column, high-purity liquefied nitrogen having a content of low boiling point components such as hydrogen of 1 ppm or less is discharged from the bottom of the auxiliary rectification column. Low-boiling components such as hydrogen can be efficiently and easily reduced at low cost, and high-purity liquefied nitrogen can be easily produced.

【００３４】また、補助精留塔底部より導出した水素等
低沸点成分の含有量１ｐｐｍ以下の高純度液化窒素の一
部を凝縮蒸発器を経て気化して水素等低沸点成分の含有
量１ｐｐｍ以下の高純度窒素ガスとして導出することに
より、製品高純度窒素ガスを採取する場合、気化に際し
て放出される寒冷をほぼ完全に回収し得、かつ蒸発器を
別途設ける必要がなく、しかも、半導体工業用の高純度
窒素ガスとすることができる。なお、このように低沸点
成分を除去した窒素を製造するために補助精留塔を設け
ることは特に既設のプラント等に好適に採用することが
できる。Also, a portion of high-purity liquefied nitrogen having a low boiling point component such as hydrogen of 1 ppm or less, which is derived from the bottom of the auxiliary rectification column, is vaporized through a condensation evaporator and the content of low boiling point component of hydrogen or the like is 1 ppm or less. When the product high-purity nitrogen gas is collected by deriving it as high-purity nitrogen gas, it is possible to almost completely recover the cold emitted during vaporization, and there is no need to install a separate evaporator. High purity nitrogen gas can be used. In addition, the provision of the auxiliary rectification column for producing nitrogen from which the low-boiling point components have been removed in this way can be suitably adopted particularly in an existing plant or the like.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明を単式精留塔に適用した第１実施例を説
明するための系統図。FIG. 1 is a system diagram for explaining a first embodiment in which the present invention is applied to a single-column rectification column.

【図２】本発明を複式精留塔の上部塔に適用した第２実
施例を説明するための系統図。FIG. 2 is a system diagram for explaining a second embodiment in which the present invention is applied to the upper column of a double rectification column.

【図３】本発明を複式精留塔の上部塔圧力状態の径路に
適用した第３実施例を説明するための系統図。FIG. 3 is a system diagram for explaining a third embodiment in which the present invention is applied to a path of a double column rectification column in a pressure state of an upper column.

【図４】本発明を複式精留塔の下部塔圧力状態の径路に
適用した第４実施例を説明するための系統図。FIG. 4 is a system diagram for explaining a fourth embodiment in which the present invention is applied to a path in a lower column pressure state of a double rectification column.

【図５】表１における水素濃度および流量を示した各部
位を示す従来の複式精留塔の系統図。FIG. 5 is a systematic diagram of a conventional double-column rectification column showing each part showing hydrogen concentration and flow rate in Table 1.

【図６】表２における水素濃度及び流量を示した各部位
を示す図３及び図４の一部拡大系統図。6 is a partially enlarged system diagram of FIG. 3 and FIG. 4 showing each part showing hydrogen concentration and flow rate in Table 2.

【図７】単式精留塔による従来の空気液化分離方法を説
明するための系統図。FIG. 7 is a system diagram for explaining a conventional air liquefaction separation method using a single-column rectification tower.

【図８】複式精留塔による従来の空気液化分離方法を説
明するための系統図。FIG. 8 is a system diagram for explaining a conventional air liquefaction separation method using a double rectification column.

【符号の説明】[Explanation of symbols]

２…単式精留塔 ６…凝縮蒸発器 １１…下部塔 １３…主凝縮蒸発器 １６，２２…過冷器 １７，２３，３５…膨張弁 １８…上部塔 ２０…膨張タービン ３０，４０，５０，６０…補助精留塔 ３２，３７，４２，４４，５２，５４，５７，６２，６
３，６４…調節弁2 ... Single-type rectification column 6 ... Condensation evaporator 11 ... Lower column 13 ... Main condensation evaporator 16, 22 ... Supercooler 17, 23, 35 ... Expansion valve 18 ... Upper column 20 ... Expansion turbine 30, 40, 50, 60 ... Auxiliary rectification tower 32,37,42,44,52,54,57,62,6
3, 64 ... Control valve

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 高純度窒素を採取する空気液化分離方法
において、主精留塔に補助精留塔を付設し、該補助精留
塔の下部に主精留塔よりの窒素ガスをその量を調節しつ
つ導入して上昇ガスとし、主精留塔より導出した液化窒
素または窒素ガスを液化して前記補助精留塔に還流液と
して、その量を調節しつつ導入して精留を行なわせ、該
補助精留塔頂部より水素等低沸点成分の含有量の多くな
った窒素ガスを導出すると共に、該補助精留塔底部より
水素等低沸点成分の含有量１ｐｐｍ以下の高純度液化窒
素を導出することを特徴とする空気液化分離方法。1. An air liquefaction separation method for collecting high-purity nitrogen, wherein an auxiliary rectification column is attached to the main rectification column, and the amount of nitrogen gas from the main rectification column is set below the auxiliary rectification column. Introduced while adjusting it as a rising gas, liquefying the liquefied nitrogen or nitrogen gas derived from the main rectification column and returning it to the auxiliary rectification column as a reflux liquid, introducing it while adjusting the amount to perform rectification. A nitrogen gas having a high content of low boiling point components such as hydrogen is discharged from the top of the auxiliary rectification column, and high-purity liquefied nitrogen having a content of low boiling point components such as hydrogen of 1 ppm or less is supplied from the bottom of the auxiliary rectification column. An air liquefaction separation method, characterized in that it is derived. 【請求項２】 高純度窒素を採取する空気液化分離方法
において、主精留塔に補助精留塔を付設し、該補助精留
塔の下部に主精留塔よりの窒素ガスをその量を調節しつ
つ導入して上昇ガスとし、主精留塔より導出した液化窒
素または窒素ガスを液化して前記補助精留塔に還流液と
して、その量を調節しつつ導入して精留を行なわせ、該
補助精留塔頂部より水素等低沸点成分の含有量の多くな
った窒素ガスを導出し、該補助精留塔底部より水素等低
沸点成分の含有量１ｐｐｍ以下の高純度液化窒素を導出
すると共に、該高純度液化窒素の一部を凝縮蒸発器を経
て気化して水素等低沸点成分の含有量１ｐｐｍ以下の高
純度窒素ガスとして導出することを特徴とする空気液化
分離方法。2. In the air liquefaction separation method for collecting high-purity nitrogen, an auxiliary rectification column is attached to the main rectification column, and the amount of nitrogen gas from the main rectification column is set below the auxiliary rectification column. Introduced while adjusting it as a rising gas, liquefying the liquefied nitrogen or nitrogen gas derived from the main rectification column and returning it to the auxiliary rectification column as a reflux liquid, introducing it while adjusting the amount to perform rectification. , Nitrogen gas having a high content of low boiling point components such as hydrogen is discharged from the top of the auxiliary rectification column, and high purity liquefied nitrogen having a content of low boiling point components such as hydrogen of 1 ppm or less is discharged from the bottom of the auxiliary rectification column. At the same time, a part of the high-purity liquefied nitrogen is vaporized through a condenser / evaporator to be discharged as high-purity nitrogen gas having a low boiling point component such as hydrogen content of 1 ppm or less.
JP4170577A 1992-06-29 1992-06-29 Air liquefaction separation method Expired - Lifetime JP2553989B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4170577A JP2553989B2 (en) 1992-06-29 1992-06-29 Air liquefaction separation method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4170577A JP2553989B2 (en) 1992-06-29 1992-06-29 Air liquefaction separation method

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP25180083A Division JPS60142184A (en) 1983-12-28 1983-12-28 Method of liquefying and separating air

Publications (2)

Publication Number Publication Date
JPH05180559A true JPH05180559A (en) 1993-07-23
JP2553989B2 JP2553989B2 (en) 1996-11-13

Family

ID=15907420

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4170577A Expired - Lifetime JP2553989B2 (en) 1992-06-29 1992-06-29 Air liquefaction separation method

Country Status (1)

Country Link
JP (1) JP2553989B2 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5241754A (en) * 1975-09-29 1977-03-31 Aisin Seiki Co Ltd Clutch construction
JPS5644577A (en) * 1979-09-19 1981-04-23 Hitachi Ltd Method of sampling pressurized nitrogen for air separator

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5241754A (en) * 1975-09-29 1977-03-31 Aisin Seiki Co Ltd Clutch construction
JPS5644577A (en) * 1979-09-19 1981-04-23 Hitachi Ltd Method of sampling pressurized nitrogen for air separator

Also Published As

Publication number Publication date
JP2553989B2 (en) 1996-11-13

Similar Documents

Publication Publication Date Title
KR100291684B1 (en) How to separate air
EP0636845B1 (en) Air separation
JP2003165712A (en) Method and apparatus for producing krypton and/or xenon by low-temperature air separation
JPH102664A (en) Low temperature distillating method for air flow of compressed raw material for manufacturing oxygen products of low purity and high purity
US4464191A (en) Cryogenic gas separation with liquid exchanging columns
PL183332B1 (en) Method of and system for separating air
KR100407184B1 (en) Cryogenic rectification system for producing ultra-high purity nitrogen and ultra-high purity oxygen
KR20010105207A (en) Cryogenic air separation system with split kettle recycle
JP2007064617A (en) Method of manufacturing krypton and/or xenon by cryogenic air separation
US5644933A (en) Air separation
JPH05288464A (en) Method and device for cryogenic rectification for producing nitrogen and ultra high purity oxygen
KR100343277B1 (en) High purity oxygen and low purity oxygen production method and apparatus
US4530708A (en) Air separation method and apparatus therefor
KR19990082696A (en) Cryogenic rectification system with serial liquid air feed
JPH05180559A (en) Air liquefaction/separation method
US6314757B1 (en) Cryogenic rectification system for processing atmospheric fluids
JPS60142183A (en) Method of liquefying and separating air
KR100390054B1 (en) Method for producing lower purity oxygen by cryogenic rectification
JPH09257365A (en) Low temperature fractionating system by stepwise condensation of feed air
JPH0526114B2 (en)
KR0137915B1 (en) Process and apparatus for producing a high purity nitrogen
JP3720863B2 (en) Air liquefaction separation method
JP2995694B2 (en) Argon production equipment
JP3254523B2 (en) Method and apparatus for purifying nitrogen
JP3072563B2 (en) Method and apparatus for collecting high-purity liquefied nitrogen

Legal Events

Date Code Title Description
EXPY Cancellation because of completion of term