JP2004232967A - Low temperature air separating device - Google Patents

Low temperature air separating device Download PDF

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Publication number
JP2004232967A
JP2004232967A JP2003022508A JP2003022508A JP2004232967A JP 2004232967 A JP2004232967 A JP 2004232967A JP 2003022508 A JP2003022508 A JP 2003022508A JP 2003022508 A JP2003022508 A JP 2003022508A JP 2004232967 A JP2004232967 A JP 2004232967A
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Prior art keywords
adsorption tower
temperature
regeneration
air
tower
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JP2003022508A
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Japanese (ja)
Inventor
Jun Yoshida
純 吉田
Taro Kano
太郎 狩野
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Hitachi Ltd
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Hitachi Ltd
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Priority to JP2003022508A priority Critical patent/JP2004232967A/en
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    • 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
    • F25J3/04769—Operation, control and regulation of the process; Instrumentation within the process
    • F25J3/04775—Air purification and pre-cooling
    • 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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
    • F25J3/0409—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression of oxygen
    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04157—Afterstage cooling and so-called "pre-cooling" of the feed air upstream the air purification unit and main heat exchange line
    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04163—Hot end purification of the feed air
    • F25J3/04169—Hot end purification of the feed air by adsorption of the impurities
    • F25J3/04181—Regenerating the adsorbents
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    • 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
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    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
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    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
    • F25J3/04206—Division of the main heat exchange line in consecutive sections having different functions including a so-called "auxiliary vaporiser" for vaporising and producing a gaseous product
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • 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
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
    • F25J3/0429—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams of feed air, e.g. used as waste or product air or expanded into an auxiliary column
    • F25J3/04303—Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • 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
    • F25J3/04763—Start-up or control of the process; Details of the apparatus used
    • F25J3/04769—Operation, control and regulation of the process; Instrumentation within the process
    • F25J3/04854—Safety aspects of operation
    • F25J3/0486—Safety aspects of operation of vaporisers for oxygen enriched liquids, e.g. purging of liquids
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/30—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes
    • F25J2205/32—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes as direct contact cooling tower to produce a cooled gas stream, e.g. direct contact after cooler [DCAC]
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/30—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes
    • F25J2205/34—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes as evaporative cooling tower to produce chilled water, e.g. evaporative water chiller [EWC]
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/60—Processes or apparatus using other separation and/or other processing means using adsorption on solid adsorbents, e.g. by temperature-swing adsorption [TSA] at the hot or cold end
    • F25J2205/66—Regenerating the adsorption vessel, e.g. kind of reactivation gas
    • F25J2205/68—Cooling the adsorption vessel
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/60—Processes or apparatus using other separation and/or other processing means using adsorption on solid adsorbents, e.g. by temperature-swing adsorption [TSA] at the hot or cold end
    • F25J2205/66—Regenerating the adsorption vessel, e.g. kind of reactivation gas
    • F25J2205/70—Heating the adsorption vessel
    • 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
    • F25J2240/00—Processes or apparatus involving steps for expanding of process streams
    • F25J2240/40—Expansion without extracting work, i.e. isenthalpic throttling, e.g. JT valve, regulating valve or venturi, or isentropic nozzle, e.g. Laval
    • F25J2240/42—Expansion without extracting work, i.e. isenthalpic throttling, e.g. JT valve, regulating valve or venturi, or isentropic nozzle, e.g. Laval the fluid being air
    • 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
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    • F25J2245/40—Processes or apparatus involving steps for recycling of process streams the recycled stream being air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • 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
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    • 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
    • F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
    • F25J2250/40—One fluid being air
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    • 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
    • F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
    • F25J2250/50—One fluid being oxygen

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Emergency Medicine (AREA)
  • Separation Of Gases By Adsorption (AREA)
  • Separation By Low-Temperature Treatments (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for controlling a low temperature air separating device having a pre-treatment device including an adsorption tower automatically controlled to optimum regenerative gas conditions. <P>SOLUTION: This low temperature air separating device with a TSA system pre-treatment device comprises a DCS control calculator 30 having a function to monitor the peak value Tp and the final value Te of the regenerative gas outlet temperature of the adsorption tower 3 and, when the monitored value comes out of a proper range, automatically correcting regenerative gas conditions. The DCS control calculator 30 comprises a function to predict the regenerative gas outlet temperature by using an air temperature Ti at an inlet to the adsorption tower 3 by automatically functionally generating the optimum values of the regenerative gas conditions subsequent to the air temperature Ti and automatically performing a control to correct that temperature. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、ＴＳＡ方式の吸着塔を含む前処理装置と該前処理装置等を制御するＤＣＳ制御計算機とを備えた酸素プラントや窒素発生装置等の深冷空気分離装置に関する。
【０００２】
【従来の技術】
原料空気圧縮機で所定の圧力まで圧縮され、前冷却装置で冷却された後、吸着塔等で水分除去、ＣＯ２除去等を行い、前処理した原料空気を原料とし、深冷分離にて酸素や窒素等の製品ガスまたは液体を精留により連続生産するプラントにおいては、プラント各所の圧力、流量、温度、液面、純度制御等はＤＣＳ（Ｄｉｓｔｒｉｂｕｔｅｄ Ｃｏｎｔｒｏｌ Ｓｙｓｔｅｍ）制御にて統合され、全体を安定運転させる制御系が構築されているのが一般的である。
【０００３】
これらの制御システムは、プラント各所のプロセスデータをＤＣＳへ取込み、各々のマイナループ制御にてそれぞれの所定のプロセス値に制御すると同時に、それぞれのループ制御を組み合わせたカスケード動作を行わせることにより、プラント全体の自動起動、定常運転、操業変更、自動停止等の工程制御もこなすシステムとなっている。
【０００４】
この、システムにおいて、前処理装置と言われる代表的な機器である吸着塔には、吸着剤の再生方法に、温度差を主に利用したＴＳＡ（Ｔｈｅｒｍａｌ Ｓｗｉｎｇ Ａｄｓｏｒｐｔｉｏｎ）方式と、主に圧力差を利用したＰＳＡ（Ｐｒｅｓｓｕｒｅ Ｓｗｉｎｇ Ａｄｓｏｒｐｔｉｏｎ）方式に大別されるが、比較的大容量の原料空気を処理するには、ＴＳＡ方式が採用されるのが一般的である。
【０００５】
ＴＳＡ方式の典型的な例は、２塔切替式があり、一定周期で、吸着運転を行った後、塔を切り替えて、「脱圧」再生ガスにより「加熱」、「再生」、「冷却」、「加圧」を行い、再び吸着運転を行うサイクルを構成する。
【０００６】
再生工程は吸着剤を所定の温度以上に加温するが、これには外部加熱源にて加熱された再生ガス（一般的には保冷槽からの廃ガス、または吸着塔にて処理された後の原料空気）を一定時間吸着塔内に導入し、吸着運転時に吸着した水分やＣＯ２を脱着する。その後の残された時間で、常温（加熱しない）再生ガスを吸着塔に導入し、再生加熱された吸着剤の冷却を行う。
【０００７】
一方、吸着剤の再生確認の一つの目安として、加熱再生工程における再生ガスの吸着塔出口温度のピーク到達温度が所定の温度まで上昇したか、否かを人間が確認して判断し、もし、ピーク到達温度が所定の温度まで上昇していない場合には、正常なレベルまで回復させるべく、吸着負荷を減らすか、再生条件を手動で調整がなされていた。
【０００８】
また、吸着器を有する深冷空気分離装置の従来技術としては、特開平９−１３３４６１号公報及び特開２００２−３１８０６９号公報において知られている。
【０００９】
【特許文献１】
特開平９−１３３４６１号公報
【特許文献２】
特開２００２−３１８０６９号公報
【００１０】
【発明が解決しようとする課題】
上記のごとく、ＴＳＡ吸着塔の再生加熱状況を最適に調整するのは、各設定値（再生ガス温度、再生ガス流量）を手動で変更し、数サイクル回してみて、再生ガス出口ピーク温度の適正確認、且つ、再生サイクル完了時の冷却温度の適正確認を行い、人間の判断で、再調整を行っている。一般に切替のサイクルは４時間程度であり、少なくとも８〜１６時間経たないと結果が出ず、その毎に調整オペレータが拘束されるという課題を有していた。
【００１１】
また、プラントの試運転時に最適に調整しても、年間の季節差による環境の変化（外気温度、外気湿度）、または原料空気圧縮機の運転圧力の変化等の外的要因により、吸着塔入口条件（水分負荷度合い）は、刻々変動している。この年間の条件差を見越した人間判断による初期調整だけでは、どうしても年間を通じての最適な条件にはならないという課題を有していた。
【００１２】
本発明の目的は、上記課題を解決すべく、最適な再生ガス条件に自動制御できるようにした吸着塔を含む前処理装置を備えた深冷空気分離装置の制御方法及びその装置を提供することにある。
【００１３】
【課題を解決するための手段】
上記目的を達成するために、本発明は、ＴＳＡ方式の前処理装置付きの深冷空気分離装置であって、吸着塔の各サイクル毎の判断データを監視、比較、内部演算して、自動的に再生条件の自動修正（再生ガス量または再生ガス温度の自動修正）機能を有するＤＣＳ制御計算機を備えたことを特徴とする。
【００１４】
即ち、本発明は、ＴＳＡ方式の前処理装置付きの深冷空気分離装置であって、ＴＳＡ方式の吸着塔への再生サイクルにおいて前記吸着塔への再生条件が適正であるか否かを自己判断し、該自己判断された結果適正でない場合には自動でその後の前記吸着塔への再生条件を制御して是正する機能を有するＤＣＳ制御計算機を備えたことを特徴とする。
【００１５】
また、本発明は、前記深冷空気分離装置のＤＣＳ制御計算機において、前記吸着塔への再生条件が適正であるか否かの自己判断を、前記吸着塔の再生ガス出口温度または前記吸着塔の入口空気温度の挙動変化の監視の基に行うことを特徴とする。
【００１６】
また、本発明は、ＴＳＡ方式の前処理装置付きの深冷空気分離装置であって、吸着塔負荷条件の悪化、および、再生ガス条件の悪化が生じた場合には、ＤＣＳ制御計算機の内部で、再生サイクルの再生ガス出口ピーク温度および終了温度を予測計算して、その後の再生サイクルでの再生ガス量と再生ガス温度の設定値をフォワード制御する機能を持たせることを特徴とする。
【００１７】
即ち、本発明は、ＴＳＡ方式の前処理装置付きの深冷空気分離装置であって、ＴＳＡ方式の吸着塔の再生ガス出口温度または前記吸着塔の入口空気温度の挙動変化を監視し、前記吸着塔への再生サイクルにおいて前記監視された前記再生ガス出口温度または前記入口空気温度の挙動変化が適正範囲にあるか否かを自己判断し、該自己判断された結果前記再生ガス出口温度または前記入口空気温度の挙動変化が適正範囲からはずれた場合には自動でその後の前記吸着塔へ導入する再生ガス温度または再生ガス量を制御して是正する機能を有するＤＣＳ制御計算機を備えたことを特徴とする。
【００１８】
また、本発明は、前記ＤＣＳ制御計算機において、さらに、前記吸着塔において異常兆候が表れたときに、このまま持続した場合の運転可能日数を内部関数で発生させて通知する機能を有することを特徴する。
【００１９】
【発明の実施の形態】
以下、本発明の実施の形態を図１乃至図６を用いて説明する。
【００２０】
本発明に係る最も簡単な実施の形態として、原料空気から酸素ガスと窒素ガスを分離する深冷空気分離装置の構成例を図１に示す。図１の空気分離プロセスは内部昇圧式と呼ばれる実施の形態であるが、本発明の主眼（特徴）とするところは吸着塔３廻りの前処理装置にあるので、吸着塔３以降のプロセスはこの図１に示す実施の形態に限定されるものでない。
【００２１】
まず、本発明に係る深冷空気分離装置の基本的な実施の形態について図１を用いて説明する。即ち、本発明は、原料空気圧縮機１にて大気から圧縮され、吸着塔３等にて前処理された空気を原料とし、深冷分離法にて原料の空気から窒素や酸素等を分離し連続生産するコールドボックス（保冷槽）５を有し、例えば製品となる酸素を液体の状態で液体酸素ポンプ１０等を利用して製品圧力まで昇圧する部分を有する深冷空気分離装置に関するものである。
【００２２】
まず、大気中の空気を吸入し、所定の圧力まで、原料空気圧縮機１で昇圧する。空気の分離は低温状態に保たれた保冷槽５の内部で行われるが、操作温度が−１７０℃〜−１８０℃となり、常温からこの温度に至る間に凝縮・固化する水分やＣＯ２成分等を除去する目的で、吸着塔３が設けられている。
【００２３】
原料空気圧縮機１で圧縮された空気は、約９０℃〜１００℃の温度で最終段吐出から出てくるが、吸着塔３での運転温度まで冷却するために、チラー水２２と冷却水２１と直接接触して熱交換を行う水洗冷却塔２で冷却され、原料空気は約１５℃以下に降下する。
【００２４】
水洗冷却塔２には、寒冷源として、クリーニングタワー等で冷却された冷却水２１と、蒸発冷却塔２０で更に温度降下したチラー水２２が供給される。通常、水洗冷却塔２の頂部へチラー水２２が、中間部へ冷却水２１が供給される。蒸発冷却塔２０では、頂部には冷却水２１が供給され、底部から乾燥した窒素ガスを蒸発冷却塔用ガスライン２３を介して供給することにより、底部へ流下した冷却水の温度は低下し、チラー水２２として、上記水洗冷却塔２の頂部へ供給される。但し、プラントの起動過程においては、保冷槽５からの戻りガス（窒素ガス）が蒸発冷却塔用ガスライン２３を介して十分に確保されないため、蒸発冷却塔起動用ガスとして、水洗冷却塔２の出口の原料空気を制御バイパス弁２５を介してバイパスさせて一時的に使用する。これを「蒸発冷却塔起動バイパス」２４と称する。
【００２５】
そして、ＡＴＳ方式の吸着塔３にて、原料空気中の水分やＣＯ２等の後段の深冷分離プロセスにとって障害となる成分を吸着除去する。吸着塔３は通常複数塔の切替式になっており、一定周期毎に吸着サイクル（例えば１５分程度の吸着運転）と再生サイクル（例えば３０分程度の再生運転）を繰り返して運転される。吸着塔３の再生には、乾燥した、保冷槽５からの戻り窒素ガスを窒素ガスライン１９を介して再生ガス加熱（電気または蒸気過熱、もしくはそれらの組み合わせ）等の外部加熱源１１にて加熱したものが導入される。この加熱再生工程の再生ガス温度は、使われる剤の種類や量により、１５０℃〜２５０℃程度が選択される。また上記再生ガスの外部加熱源１１としては、電気ヒータや蒸気ヒータ、または両者の組み合わせで行われる。
【００２６】
但し、プラントの起動過程においては、保冷槽５からの戻りのガスが窒素ガスライン１９を介して十分に確保されないため、吸着塔３の再生ガス２９として、吸着塔３の出口の原料空気を制御バイパス弁２７を介して窒素ガスライン１９にバイパスさせ、該ガスライン１９から再生ガスライン２９に供給して一時的に使用する。これを「吸着塔起動バイパス」２６と称する。なお、蒸発冷却塔用ガスライン２３に設けた制御弁２８によって、それぞれのラインの圧力が適正になるよう調整される。
【００２７】
吸着塔３を出た原料空気は、製品のガスに製品分離される保冷槽５へ供給される。原料空気は、保冷槽５内の空気熱交換器１３にて液化点近傍まで冷却され、精留塔８へ供給され、一部は寒冷発生用の膨張タービン８への空気として抽気される。
【００２８】
例えば内部昇圧式の中圧酸素ガスを取り出すプラントにおいては、製品酸素を深冷状態で精留分離する精留塔は、下塔（中圧塔）８と上塔（低圧塔）７から構成され、両者は主凝縮器４０にて互いに熱交換を行う。この主凝縮器４０には下塔８の上部から窒素ガスが供給され、液化された窒素は下塔８の上部に戻される。即ち、精留塔は、送り込まれた原料空気を窒素ガスと酸素分に富んだ液体空気に精留分離する下塔８と、下塔８の底部より抜出された液体空気及び下塔８から抜出された液体不純窒素を過冷却する過冷却器１２と、タービンコンプレッサにより昇圧されるか或いはそのままの圧力で、同じく熱交換器１３により温度降下し、必要寒冷を発生する膨張タービン６にて大気圧近くまで膨張して原料空気として流入し、上記過冷却器１２で過冷却されて送られてきた液体空気及び液体不純窒素を精留して底部から液体酸素を取り出す上塔７とを備えて構成される。なお、上塔７の頂部から得られる窒素ガスは、過冷却器１２において、寒冷の一部を下塔８からの液体空気及び液体不純窒素に渡して過冷却することになる。そして、これら上塔７と下塔８の圧力関係は、主凝縮器４０の温度差で決まる飽和温度に相当する圧力にて運転される。
【００２９】
また、精留塔では、原料の深冷空気（蒸気）を上昇させ、上部の窒素凝縮器７から流下する液体と直接接触させて精留することにより、高純度の製品窒素ガスおよび製品液体窒素を低温状態で塔頂部から抽出する。なお、全体の寒冷をバランスさせるために膨張タービン６が設けられている。
【００３０】
更に、例えば、精留塔上塔７の底部から抽出されて液体酸素ポンプ１０にて所定の圧力に加圧された液体酸素は、液体酸素ドラム（液体酸素蒸発器）９において、その飽和温度より更に高い飽和温度となる空気昇圧器４から得られる昇圧空気と液体酸素熱交換器４１により間接的に熱交換されて所定圧力の製品酸素ガスとして蒸発し、更に常温まで温度回復され、より多くの製品酸素ガス４２としてプラントから取り出されることになる。また、液体酸素ドラム９内の液体酸素は、蒸発器１４によって蒸発して製品酸素ガス４２として取り出されることになる。
【００３１】
次に、本発明の特徴とするＤＣＳ（Ｄｉｓｔｒｉｂｕｔｅｄ Ｃｏｎｔｒｏｌ Ｓｙｓｔｅｍ）制御機能を利用し、吸着塔３の再生条件（再生ガス温度又は再生ガス量）を自己判断して適正条件からはずれた場合には、自動で条件改善を行って上記再生条件を是正する吸着塔３廻りの前処理装置の自動制御方法及びその装置の実施例について説明する。図２には本発明に係るＴＳＡ吸着塔再生工程における再生ガスの吸着塔出口温度の１サイクルあたりの温度挙動例を示す。図３には本発明に係るＴＳＡ吸着塔再生工程における自己最適制御の制御フローの一実施例を示す。図４及び図５には本発明に係るＴＳＡ吸着塔再生工程の自己最適制御の一実施例を示し、図６には他の実施例を示す。本発明に係る深冷空気分離装置においては、吸着塔３の再生には保冷槽５からの戻りガス１９の一部が利用される。先ず、吸着塔再生サイクルとして、内部脱圧後、保冷槽５からガスライン１９によって得られる窒素ガス等の再生ガスをライン５１において加熱ヒータ（外部加熱源）１１で所定温度まで加熱して吸着塔３に初期の規定時間導入し、吸着剤を一定時間加熱再生する。その後、常温の再生ガスをライン５２を通して吸着塔３に導入し、吸着塔３内部を吸着サイクルへの切替に耐え得る温度まで冷却する。このように再生ガス温度で示される加熱された再生ガスを入口２９から吸着塔３に導入したとき、図２に示すように、出口側（再生ガス出口温度）の温度挙動は、再生ガス入口より時間的に遅れてピークを示し、その後、切替末期まで常温の再生ガス温度に漸近していくことになる（決められた切替サイクル時間の中で、最終的に所定の温度まで冷却されなければならない。）。そこで、吸着塔３の再生工程（再生サイクル）において、自己判断する吸着塔３の再生条件（再生ガス温度又は再生ガス量）として例えば再生ガスブロー温度（再生ガス出口温度）を温度計測器ＴＩ（３５）で計測してＤＣＳ（分配制御システム：Ｄｉｓｔｒｉｂｕｔｅｄ Ｃｏｎｔｒｏｌ Ｓｙｓｔｅｍ）制御計算機３０に入力し、ＤＣＳ制御計算機３０は、再生ガスブロー温度の挙動を一定時間毎に監視し、それぞれの再生サイクルにおける再生ガス出口温度のピーク温度（Ｔｐ）を自動検出して例えば記憶装置３３に記憶する（ステップＳ３０１）。なお、ＤＣＳ制御計算機３０が再生ガス出口温度のピーク温度を自動検出する際、温度勾配の反転点のうち最も高い点を抽出することによって行う。
【００３２】
そして、ＤＣＳ制御計算機３０は、上記自動検出して記憶されたピーク温度Ｔｐの値を例えば記憶装置３３に予め入力手段３１を用いて入力して記憶された適正条件としての設計上の許容範囲（例えば１０５℃〜１１０℃）と比較してピーク温度Ｔｐの値が例えば１０５℃〜１１０℃の範囲内にあると判断した場合には、吸着塔３は健全であると判断し、再生条件の修正制御は行わない（ステップＳ３０２）。さらに、ＤＣＳ制御計算機３０は、再生条件が適正条件からはずれて適正でないと判断した場合、例えばピーク温度Ｔｐの値が規定値（例えば１０８℃）以下になったと判断した場合には、Ｔｐの規定値からの乖離の度合いによって再生条件悪化の傾向にあるか否かを判断し（ステップＳ３０３）、再生条件悪化の傾向にあると判断されたとき、例えば表示装置３２に対して「吸着塔再生条件改善動作自動実行します。」を発報し（ステップＳ３０４）、「吸着塔再生条件改善動作自動実行」に移行することになる。
【００３３】
ＤＣＳ制御計算機３０は、「吸着塔再生条件改善動作自動実行」に移行すると、自動で再生条件改善を行って該再生条件を是正すべく、例えば図４（ａ）に示すように、▲１▼加熱ヒータ（外部加熱源）１１に対して次回の吸着塔再生温度制御設定値ＳＶｔ（℃）（該設定値ＳＶｔは、温度計測器ＴＩ（３５）で一定時間毎に計測される再生ガス出口温度の挙動を基に吸着塔３に導入する再生ガス温度との関係から予測計算される再生ガス出口のピーク温度Ｔｐに基づいて設定される。この際、吸着塔３に導入する再生ガスの温度を温度計測器ＴＩ（図示せず）で計測しても良い。）を上昇させるフォワード制御を行う（ステップＳ３０５）。ＤＣＳ制御計算機３０は、これでも温度計測器ＴＩ（３５）で計測されるピーク温度Ｔｐの値が適正値におさまらぬ場合には、次の段階の制御として、例えば図４（ｂ）に示すように、▲２▼流量制御弁１８、３７に対して再生ガスの風量の流量制御設定値ＳＶｑ（Ｎｍ３／ｈ）（該設定値ＳＶｑは、温度計測器ＴＩ（３５）で一定時間毎に計測される再生ガス出口温度の挙動を基に吸着塔３に導入する再生ガス流量との関係から予測計算される再生ガス出口のピーク温度Ｔｐに基づいて設定される。この際、吸着塔３に導入する再生ガスの流量を流量計測器ＦＩ（図示せず）で計測しても良い。）を上昇させるフォワード制御を行う（ステップＳ３０６）。
【００３４】
これらの制御により、常に再生ガス出口温度のピーク値Ｔｐを適正範囲に保ち、吸着塔３の破過に至る状況を自動で回避することが出来る。また、ＤＣＳ制御計算機３０は、上記ピーク値Ｔｐが過剰に高いと判断した場合には、再生条件が過剰であることから、逆に再生ガス温度を下げる制御を加熱ヒータ１１に対して行い、再生風量を下げる制御を流量制御弁１８に対して行い、常に加熱ヒータ１１に対して最小の再生加熱エネルギ消費点にて運転されるため、余計な運転電力消費量や蒸気消費量を自動で押さえることも可能となる。
【００３５】
但し、上記▲１▼の制御修正において、再生工程終了時の再生ガス出口温度Ｔｅがある規定値以下でないと、吸着サイクルへの切替後のプロセスガス温度が上がり、後流側の一時的な温度上昇を招くと同時に、保冷槽５からの戻りガス（再生ガスや蒸発冷却塔２０へのガス）温度もこれにつられて上昇する。この結果、水洗冷却塔２の出口空気（吸着塔入口空気）温度が上昇気味になり、その分、吸着塔３への水分負荷が増大し、悪循環となる。このため、ＤＣＳ制御計算機３０は、図５（ａ）に示すように、温度計測器ＴＩ（３５）で一定時間毎に吸着塔再生工程終了時において計測される再生ガス出口温度の挙動を基に吸着塔３に導入する再生ガス温度との関係から予測計算される吸着塔再生工程終了時における再生ガス出口温度Ｔｅが既定値以下に下がるといった前提条件のもとで（即ち、予測計算される再生工程終了時における再生ガス出口温度Ｔｅが適正許容幅に入るように）、上記▲１▼をフォワード制御する。この際、図５（ｂ）に示すように、上記▲２▼をフォワード制御してもよい。これにより、自動的に再生ガス条件変更による吸着塔３の負荷増大の防止も自動で行うことが可能となる。
【００３６】
次に、ＴＳＡ吸着塔再生工程の自己最適制御の更に発展した他の実施例について説明する。この他の実施例として、原料空気の吸着塔３への入口温度Ｔｉは、季節毎の外気温度変化や外気湿度変化で変わっていく。これにつれて、吸着塔３の水分負荷も変わり、結果として吸着塔３の再生時ガス出口ピーク温度値Ｔｐも変化することになる。そこで、ＤＣＳ制御計算機３０は、温度計測器ＴＩ（３６）で計測される吸着塔入口空気温度Ｔｉの挙動変化を長期的に自動判断し、その結果、図６に示すように、上記計測される吸着塔入口空気温度（Ｔｉ）が適正な範囲になるように、吸着塔３の再生条件（例えば加熱ヒータ１１に対する再生ガス温度制御設定値ＳＶｔ）を、温度計測器ＴＩ（３６）で計測される吸着塔入口空気温度Ｔｉの例えば平均値の関数として自動制御することにより、吸着に引き続く次の再生時に是正制御を自動で行うことが出来る。即ち、ＤＣＳ制御計算機３０は、上記計測される吸着塔３への入口の空気温度（Ｔｉ）からそれに続く再生条件の最適値を自動で関数発生させて再生ガス出口温度を予測演算し、それを是正する制御を自動的に行う。
【００３７】
また、ＤＣＳ制御計算機３０は、例えば温度計測器ＴＩ（３５）で計測される吸着塔３の再生ガス出口温度（Ｔｐ若しくはＴｅ）または温度計測器ＴＩ（３６）で計測される吸着塔入口空気温度（Ｔｉ）の挙動変化を監視して吸着塔への再生条件または吸着塔への吸着負荷に異常兆候が表れたときに、このまま持続した場合の運転可能日数を内部関数で発生させて例えば表示装置３２に表示する等出力する通知機能を有することによって、深冷空気分離装置の管理者に通知することが可能となる。
【００３８】
【発明の効果】
以上説明したように、本発明によれば、深冷空気分離装置において、吸着塔の再生条件を適正に自動制御するように構成したことにより、従来運転員の毎回の記録確認や、予想による制御調整にて行われていた、調整制御が不要となるとともに、調整漏れによる吸着塔の破過といった最悪の事態を未然防止することが可能となる効果を奏する。
【００３９】
また、本発明によれば、年間を通じて吸着塔の再生に係わる電力や蒸気量を自動で最小にできる効果を奏する。
【図面の簡単な説明】
【図１】本発明に係る深冷空気分離装置の一実施の形態（内部昇圧式の場合）を示す構成図である。
【図２】本発明に係るＴＳＡ吸着塔再生工程における再生ガスの吸着塔出口温度の１サイクルあたりの温度挙動例を示す図である。
【図３】本発明に係るＴＳＡ吸着塔再生工程における自己最適制御の制御フローの一実施例を説明するための図である。
【図４】本発明に係るＴＳＡ吸着塔再生工程の自己最適制御の一実施例を説明するための図である。
【図５】本発明に係るＴＳＡ吸着塔再生工程の自己最適制御の一実施例を説明するための図である。
【図６】本発明に係るＴＳＡ吸着塔再生工程の自己最適制御の他の実施例を説明するための図である。
【符号の説明】
１…原料空気圧縮機、２…冷却塔（水洗冷却塔）、３…吸着塔、５…コールドボックス（保冷槽）、６…膨張タービン、７…精留塔（上塔）、８…精留塔（下塔）、９…液体酸素ドラム、１０…液体酸素ポンプ、１１…再生ガス加熱ヒータ（外部加熱源）、１２…過冷却器、１３…空気熱交換器、１４…蒸発器、１８…再生ガス流量制御弁、１９…ガスライン、２０…蒸発冷却塔、２３…蒸発冷却塔用ガスライン、２４…蒸発冷却塔起動バイパス、２６…吸着塔起動バイパス、２９…再生ガスライン（入口）、３０…ＤＣＳ制御計算機、３１…入力手段、３２…表示装置、３３…記憶装置、３５、３６…温度計測器ＴＩ、４２…製品酸素ガスライン、５１、５２…ライン。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cryogenic air separation apparatus such as an oxygen plant or a nitrogen generator equipped with a pretreatment apparatus including a TSA type adsorption tower and a DCS control computer for controlling the pretreatment apparatus and the like.
[0002]
[Prior art]
After being compressed to a predetermined pressure by a raw air compressor and cooled by a pre-cooling device, water is removed by an adsorption tower or the like, CO 2 is removed, and the pretreated raw material air is used as a raw material, and oxygen is obtained by deep cooling. In a plant that continuously produces product gas or liquid such as nitrogen and rectified by rectification, the pressure, flow rate, temperature, liquid level, purity control, etc. of each part of the plant are integrated by DCS (Distributed Control System) control, and the whole is stable In general, a control system to be operated is constructed.
[0003]
These control systems take in process data from various parts of the plant to the DCS and control them to their respective predetermined process values in each minor loop control, and at the same time, perform a cascade operation combining the respective loop controls, thereby This system also handles process control such as automatic start-up, steady operation, operation change, and automatic stop.
[0004]
In this system, an adsorption tower, which is a typical device called a pretreatment device, has a TSA (Thermal Swing Adsorption) method mainly using a temperature difference as a method for regenerating the adsorbent, and a pressure difference mainly. Although generally classified into PSA (Pressure Swing Adsorption) method, the TSA method is generally adopted to process a relatively large volume of raw material air.
[0005]
A typical example of the TSA method is a two-column switching type. After performing an adsorption operation at a fixed period, the column is switched, and “heating”, “regeneration”, “cooling” is performed by “depressurization” regeneration gas. , "Pressurization" is performed, and a cycle in which the adsorption operation is performed again is configured.
[0006]
In the regeneration step, the adsorbent is heated to a predetermined temperature or more, and this is caused by a regeneration gas heated by an external heating source (generally, waste gas from a cold storage tank or after being treated in an adsorption tower). The raw material air) is introduced into the adsorption tower for a certain period of time, and moisture and CO 2 adsorbed during the adsorption operation are desorbed. After that, the room temperature (not heated) regeneration gas is introduced into the adsorption tower, and the regenerated and heated adsorbent is cooled.
[0007]
On the other hand, as one guideline for the regeneration confirmation of the adsorbent, a human confirms whether or not the peak arrival temperature of the adsorption tower outlet temperature of the regeneration gas in the heating regeneration process has increased to a predetermined temperature. When the peak temperature has not risen to a predetermined temperature, the adsorption load has been reduced or the regeneration conditions have been adjusted manually in order to recover to a normal level.
[0008]
Moreover, as a prior art of the cryogenic air separation apparatus which has an adsorption device, it is known in Unexamined-Japanese-Patent No. 9-133461 and Unexamined-Japanese-Patent No. 2002-318069.
[0009]
[Patent Document 1]
JP-A-9-133461 [Patent Document 2]
Japanese Patent Laid-Open No. 2002-318069
[Problems to be solved by the invention]
As described above, the optimum adjustment of the regeneration heating status of the TSA adsorption tower can be achieved by manually changing each set value (regeneration gas temperature, regeneration gas flow rate) and turning it several cycles to determine the appropriate regeneration gas outlet peak temperature. Confirmation and proper confirmation of the cooling temperature at the completion of the regeneration cycle are performed, and readjustment is performed by human judgment. In general, the switching cycle is about 4 hours, and if at least 8 to 16 hours have not passed, the result is not obtained, and the adjustment operator is restricted every time.
[0011]
In addition, even if the plant is optimally adjusted during the trial operation of the plant, the conditions of the inlet of the adsorption tower may be affected by external factors such as changes in the environment due to seasonal differences (outside air temperature, outside air humidity) or changes in the operating pressure of the raw material air compressor. (Moisture load degree) changes every moment. The initial adjustment based on human judgment in anticipation of this year's condition difference alone has a problem that the optimum condition is not necessarily achieved throughout the year.
[0012]
An object of the present invention is to provide a method for controlling a cryogenic air separation apparatus having a pretreatment device including an adsorption tower that can be automatically controlled to an optimum regeneration gas condition and an apparatus for solving the above problems. It is in.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is a cryogenic air separation apparatus with a TSA type pretreatment device, which automatically monitors judgment, comparison, and internal calculation for each cycle of the adsorption tower. Is provided with a DCS control computer having a function of automatically correcting regeneration conditions (automatic correction of regeneration gas amount or regeneration gas temperature).
[0014]
That is, the present invention is a cryogenic air separation apparatus with a TSA type pretreatment device, and it is self-determining whether the regeneration conditions for the adsorption tower are appropriate in the regeneration cycle for the TSA type adsorption tower. In addition, if the self-determined result is not appropriate, a DCS control computer having a function of automatically controlling and correcting the subsequent regeneration conditions for the adsorption tower is provided.
[0015]
In the DCS control computer of the cryogenic air separation apparatus, the present invention may determine whether or not the regeneration conditions for the adsorption tower are appropriate by determining whether or not the regeneration gas outlet temperature of the adsorption tower or the adsorption tower It is characterized in that it is performed based on monitoring of changes in the behavior of the inlet air temperature.
[0016]
Further, the present invention is a chilled air separation apparatus with a TSA type pretreatment device, and when the deterioration of the adsorption tower load condition and the deterioration of the regeneration gas condition occur, the inside of the DCS control computer. The regeneration gas outlet peak temperature and end temperature of the regeneration cycle are predicted and calculated, and a function of forward-controlling the regeneration gas amount and regeneration gas temperature set values in the subsequent regeneration cycle is provided.
[0017]
That is, the present invention is a cryogenic air separation apparatus with a TSA type pretreatment device, which monitors the behavior change of the regeneration gas outlet temperature of the TSA type adsorption tower or the inlet air temperature of the adsorption tower, and In the regeneration cycle to the tower, it is self-determined whether the monitored change in the regeneration gas outlet temperature or the inlet air temperature is within an appropriate range, and the self-determination result indicates the regeneration gas outlet temperature or the inlet. A DCS control computer having a function of automatically controlling and correcting the regeneration gas temperature or the amount of regeneration gas introduced to the adsorption tower when the change in behavior of the air temperature deviates from the appropriate range. To do.
[0018]
Further, the present invention is characterized in that, in the DCS control computer, when an abnormal sign appears in the adsorption tower, it has a function of notifying the number of days that can be operated with an internal function when it continues as it is. .
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0020]
As a simplest embodiment according to the present invention, FIG. 1 shows a configuration example of a cryogenic air separation device for separating oxygen gas and nitrogen gas from raw material air. Although the air separation process of FIG. 1 is an embodiment called an internal boosting type, the main feature (feature) of the present invention is the pretreatment device around the adsorption tower 3, and the process after the adsorption tower 3 is this. It is not limited to the embodiment shown in FIG.
[0021]
First, a basic embodiment of a cryogenic air separation device according to the present invention will be described with reference to FIG. That is, the present invention uses air compressed by the raw material air compressor 1 and pretreated by the adsorption tower 3 or the like as a raw material, and separates nitrogen, oxygen, etc. from the raw material air by a cryogenic separation method. The present invention relates to a cryogenic air separation apparatus having a cold box (cold storage tank) 5 for continuous production and having a portion for increasing the pressure of a product to a product pressure using a liquid oxygen pump 10 or the like in a liquid state, for example. .
[0022]
First, air in the atmosphere is sucked and the pressure is increased by the raw material air compressor 1 to a predetermined pressure. Air separation is performed inside the cold storage tank 5 kept at a low temperature, but the operating temperature is -170 ° C to -180 ° C, and moisture, CO 2 components, etc. that condense and solidify from room temperature to this temperature. An adsorption tower 3 is provided for the purpose of removing water.
[0023]
The air compressed by the raw material air compressor 1 comes out from the final stage discharge at a temperature of about 90 ° C. to 100 ° C. In order to cool to the operating temperature in the adsorption tower 3, chiller water 22 and cooling water 21 are used. The raw air is cooled to about 15 ° C. or less as it is cooled by the water-washing cooling tower 2 that performs direct heat contact with the water washing.
[0024]
As the cooling source, the water washing cooling tower 2 is supplied with cooling water 21 cooled by a cleaning tower or the like and chiller water 22 further lowered in temperature by the evaporative cooling tower 20. Usually, chiller water 22 is supplied to the top of the water-washing cooling tower 2 and cooling water 21 is supplied to the intermediate part. In the evaporative cooling tower 20, the cooling water 21 is supplied to the top, and the nitrogen gas dried from the bottom is supplied via the evaporative cooling tower gas line 23, so that the temperature of the cooling water flowing down to the bottom decreases. The chiller water 22 is supplied to the top of the flush cooling tower 2. However, in the start-up process of the plant, the return gas (nitrogen gas) from the cold storage tank 5 is not sufficiently secured via the evaporative cooling tower gas line 23, so that the washing cooling tower 2 is used as the evaporative cooling tower start gas. The raw material air at the outlet is bypassed via the control bypass valve 25 and temporarily used. This is referred to as “evaporative cooling tower activation bypass” 24.
[0025]
Then, the ATS type adsorption tower 3 adsorbs and removes components that hinder the subsequent cryogenic separation process such as moisture in the raw material air and CO 2 . The adsorption tower 3 is usually a switching type of a plurality of towers, and is operated by repeating an adsorption cycle (for example, an adsorption operation of about 15 minutes) and a regeneration cycle (for example, a regeneration operation of about 30 minutes) at regular intervals. For regeneration of the adsorption tower 3, the dried return nitrogen gas from the cold storage tank 5 is heated by an external heating source 11 such as regeneration gas heating (electrical or steam overheating, or a combination thereof) through a nitrogen gas line 19. Will be introduced. The regeneration gas temperature in this heating regeneration step is selected to be about 150 ° C. to 250 ° C. depending on the type and amount of the agent used. The regeneration gas external heating source 11 is an electric heater, a steam heater, or a combination of both.
[0026]
However, in the start-up process of the plant, the return gas from the cold storage tank 5 is not sufficiently secured through the nitrogen gas line 19, so the raw air at the outlet of the adsorption tower 3 is controlled as the regeneration gas 29 of the adsorption tower 3. The gas is bypassed to the nitrogen gas line 19 via the bypass valve 27 and supplied to the regeneration gas line 29 from the gas line 19 to be temporarily used. This is referred to as an “adsorption tower activation bypass” 26. In addition, the pressure of each line is adjusted by the control valve 28 provided in the gas line 23 for evaporative cooling towers.
[0027]
The raw air leaving the adsorption tower 3 is supplied to a cold storage tank 5 where the product is separated into product gas. The raw material air is cooled to the vicinity of the liquefaction point by the air heat exchanger 13 in the cold storage tank 5, supplied to the rectification tower 8, and a part thereof is extracted as air to the expansion turbine 8 for generating cold.
[0028]
For example, in a plant for taking out internal pressure oxygen gas having an internal boosting type, a rectifying column for rectifying and separating product oxygen in a deep cooling state is composed of a lower column (medium pressure column) 8 and an upper column (low pressure column) 7. Both exchange heat with each other in the main condenser 40. Nitrogen gas is supplied to the main condenser 40 from the upper part of the lower tower 8, and the liquefied nitrogen is returned to the upper part of the lower tower 8. That is, the rectifying tower is composed of a lower tower 8 that rectifies and separates the fed raw material air into liquid air rich in nitrogen gas and oxygen, and liquid air extracted from the bottom of the lower tower 8 and the lower tower 8. A supercooler 12 that supercools the extracted liquid impure nitrogen, and an expansion turbine 6 that generates a necessary cold by the pressure being increased by the turbine compressor or by the heat exchanger 13 at the same pressure. An upper tower 7 is provided that expands to near atmospheric pressure and flows in as raw material air, and rectifies liquid air and liquid impure nitrogen that are supercooled by the supercooler 12 and extracts liquid oxygen from the bottom. Configured. The nitrogen gas obtained from the top of the upper tower 7 is supercooled in the supercooler 12 by passing a part of the cold to the liquid air and liquid impure nitrogen from the lower tower 8. The pressure relationship between the upper tower 7 and the lower tower 8 is operated at a pressure corresponding to the saturation temperature determined by the temperature difference of the main condenser 40.
[0029]
Further, in the rectification tower, the raw material chilled air (steam) is raised and rectified by direct contact with the liquid flowing down from the upper nitrogen condenser 7 to obtain high purity product nitrogen gas and product liquid nitrogen. Is extracted from the top of the column at low temperature. An expansion turbine 6 is provided in order to balance the whole cold.
[0030]
Furthermore, for example, liquid oxygen extracted from the bottom of the rectifying tower upper column 7 and pressurized to a predetermined pressure by the liquid oxygen pump 10 is discharged from the saturation temperature in the liquid oxygen drum (liquid oxygen evaporator) 9. Further, heat is indirectly exchanged with the pressurized air obtained from the air pressure booster 4 having a higher saturation temperature and the liquid oxygen heat exchanger 41 to evaporate as a product oxygen gas at a predetermined pressure, and the temperature is recovered to room temperature. The product oxygen gas 42 is taken out from the plant. The liquid oxygen in the liquid oxygen drum 9 is evaporated by the evaporator 14 and taken out as product oxygen gas 42.
[0031]
Next, when the DCS (Distributed Control System) control function, which is a feature of the present invention, is used and the regeneration condition (regeneration gas temperature or amount of regeneration gas) of the adsorption tower 3 is self-determined and deviates from the appropriate condition, An automatic control method of the pretreatment apparatus around the adsorption tower 3 for automatically improving the conditions and correcting the regeneration conditions will be described. FIG. 2 shows an example of a temperature behavior per cycle of the regeneration tower outlet temperature of the regeneration gas in the TSA adsorption tower regeneration step according to the present invention. FIG. 3 shows an embodiment of a control flow of self-optimal control in the TSA adsorption tower regeneration process according to the present invention. 4 and 5 show an embodiment of self-optimal control of the TSA adsorption tower regeneration process according to the present invention, and FIG. 6 shows another embodiment. In the cryogenic air separation apparatus according to the present invention, a part of the return gas 19 from the cold storage tank 5 is used for the regeneration of the adsorption tower 3. First, as an adsorption tower regeneration cycle, after internal pressure reduction, a regeneration gas such as nitrogen gas obtained from the cold storage tank 5 through the gas line 19 is heated to a predetermined temperature in a line 51 by a heater (external heating source) 11 to the adsorption tower. 3 is introduced for an initial specified time, and the adsorbent is heated and regenerated for a certain time. Thereafter, normal temperature regeneration gas is introduced into the adsorption tower 3 through the line 52, and the inside of the adsorption tower 3 is cooled to a temperature that can withstand switching to the adsorption cycle. When the heated regeneration gas indicated by the regeneration gas temperature is introduced into the adsorption tower 3 from the inlet 29, the temperature behavior on the outlet side (regeneration gas outlet temperature) is as shown in FIG. It shows a peak with a delay in time, and then gradually approaches the normal regeneration gas temperature until the end of switching (in the determined switching cycle time, it must finally be cooled to a predetermined temperature) .) Therefore, in the regeneration step (regeneration cycle) of the adsorption tower 3, for example, the regeneration gas blow temperature (regeneration gas outlet temperature) is set as the temperature measuring device TI (35) as the regeneration condition (regeneration gas temperature or regeneration gas amount) of the adsorption tower 3 to be self-determined. ) And is input to a DCS (Distributed Control System) control computer 30. The DCS control computer 30 monitors the behavior of the regeneration gas blow temperature at regular intervals, and the regeneration gas outlet temperature in each regeneration cycle. The peak temperature (Tp) is automatically detected and stored in, for example, the storage device 33 (step S301). In addition, when the DCS control computer 30 automatically detects the peak temperature of the regeneration gas outlet temperature, it is performed by extracting the highest point among the inversion points of the temperature gradient.
[0032]
Then, the DCS control computer 30 inputs the value of the peak temperature Tp automatically detected and stored in the storage device 33 by using the input means 31 in advance and stores it as an appropriate design tolerance ( For example, if it is determined that the peak temperature Tp is within the range of 105 ° C. to 110 ° C., for example, the adsorption tower 3 is determined to be healthy and the regeneration condition is corrected. Control is not performed (step S302). Furthermore, if the DCS control computer 30 determines that the regeneration condition is not appropriate and is not appropriate, for example, if it is determined that the value of the peak temperature Tp is equal to or less than a specified value (for example, 108 ° C.), the specified Tp is specified. It is determined whether or not there is a tendency for the regeneration condition to deteriorate depending on the degree of deviation from the value (step S303). "Improvement operation is automatically executed" is issued (step S304), and the process proceeds to "Adsorption tower regeneration condition improvement operation automatic execution".
[0033]
When the DCS control computer 30 shifts to “automatic execution of the adsorption tower regeneration condition improvement operation”, as shown in FIG. 4A, for example, as shown in FIG. The next adsorption tower regeneration temperature control set value SVt (° C.) for the heater (external heating source) 11 (this set value SVt is the regeneration gas outlet temperature measured at regular intervals by the temperature measuring device TI (35)). Is set based on the peak temperature Tp of the regeneration gas outlet that is predicted and calculated from the relationship with the regeneration gas temperature introduced into the adsorption tower 3 based on the above behavior. Forward control for raising the temperature measuring instrument TI (not shown) may be performed (step S305). If the value of the peak temperature Tp measured by the temperature measuring instrument TI (35) still does not fall within the appropriate value, the DCS control computer 30 performs, for example, as shown in FIG. (2) The flow rate control set value SVq (Nm 3 / h) of the regeneration gas flow rate with respect to the flow rate control valves 18 and 37 (this set value SVq is measured at regular intervals by the temperature measuring instrument TI (35)). It is set based on the peak temperature Tp of the regeneration gas outlet that is predicted and calculated from the relationship with the regeneration gas flow rate introduced into the adsorption tower 3 based on the behavior of the regeneration gas outlet temperature that is introduced. The flow rate of the regeneration gas to be measured may be measured by a flow rate measuring device FI (not shown)) (step S306).
[0034]
By these controls, the peak value Tp of the regeneration gas outlet temperature can always be kept in an appropriate range, and the situation of breakthrough of the adsorption tower 3 can be automatically avoided. On the other hand, when the DCS control computer 30 determines that the peak value Tp is excessively high, the regeneration condition is excessive. Therefore, the DCS control computer 30 controls the heater 11 to lower the regeneration gas temperature and regenerates the regeneration. The flow rate control valve 18 is controlled to reduce the air volume, and the heater 11 is always operated at the minimum regeneration heating energy consumption point, so that unnecessary operating power consumption and steam consumption can be automatically suppressed. Is also possible.
[0035]
However, in the control correction of (1) above, if the regeneration gas outlet temperature Te at the end of the regeneration process is not less than a specified value, the process gas temperature after switching to the adsorption cycle rises, and a temporary temperature on the downstream side Simultaneously with the rise, the temperature of the return gas (regeneration gas and gas to the evaporative cooling tower 20) from the cold storage tank 5 rises accordingly. As a result, the temperature of the outlet air (adsorption tower inlet air) of the washing / cooling tower 2 rises, and the moisture load on the adsorption tower 3 increases correspondingly, resulting in a vicious cycle. Therefore, as shown in FIG. 5A, the DCS control computer 30 is based on the behavior of the regeneration gas outlet temperature measured at the end of the adsorption tower regeneration process at regular intervals by the temperature measuring device TI (35). Under the precondition that the regeneration gas outlet temperature Te at the end of the adsorption tower regeneration process, which is predicted and calculated from the relationship with the regeneration gas temperature introduced into the adsorption tower 3, falls below a predetermined value (that is, the regeneration that is predicted and calculated). (1) is forward-controlled so that the regeneration gas outlet temperature Te at the end of the process falls within an appropriate allowable range. At this time, as shown in FIG. 5 (b), the above (2) may be forward controlled. As a result, it is possible to automatically prevent an increase in the load on the adsorption tower 3 by automatically changing the regeneration gas condition.
[0036]
Next, another embodiment in which the self-optimal control of the TSA adsorption tower regeneration process is further developed will be described. As another example, the inlet temperature Ti of the raw material air to the adsorption tower 3 changes with the change in the outside air temperature and the change in the outside air humidity every season. Accordingly, the moisture load of the adsorption tower 3 also changes, and as a result, the gas outlet peak temperature value Tp during regeneration of the adsorption tower 3 also changes. Therefore, the DCS control computer 30 automatically determines a long-term change in the behavior of the adsorption tower inlet air temperature Ti measured by the temperature measuring instrument TI (36). As a result, as shown in FIG. The regeneration condition of the adsorption tower 3 (for example, the regeneration gas temperature control set value SVt for the heater 11) is measured by the temperature measuring device TI (36) so that the adsorption tower inlet air temperature (Ti) falls within an appropriate range. By automatically controlling, for example, a function of the average value of the adsorption tower inlet air temperature Ti, correction control can be automatically performed at the next regeneration following adsorption. That is, the DCS control computer 30 automatically generates a function of the optimum value of the subsequent regeneration conditions from the measured air temperature (Ti) of the inlet to the adsorption tower 3 to predict and calculate the regeneration gas outlet temperature. Automatic control to correct.
[0037]
Further, the DCS control computer 30 is configured such that, for example, the regeneration gas outlet temperature (Tp or Te) of the adsorption tower 3 measured by the temperature measuring instrument TI (35) or the adsorption tower inlet air temperature measured by the temperature measuring instrument TI (36). When the behavior change of (Ti) is monitored and an abnormal sign appears in the regeneration condition for the adsorption tower or the adsorption load on the adsorption tower, the number of days that can be operated is maintained as an internal function. By having a notification function for displaying the information on the display 32, it is possible to notify the administrator of the deep air separation apparatus.
[0038]
【The invention's effect】
As described above, according to the present invention, in the cryogenic air separation device, the regeneration condition of the adsorption tower is configured to be automatically and appropriately controlled. There is an effect that adjustment control, which has been performed by adjustment, becomes unnecessary, and it is possible to prevent the worst situation such as breakthrough of the adsorption tower due to adjustment leakage.
[0039]
Moreover, according to this invention, there exists an effect which can minimize automatically the electric power and steam quantity which are related to regeneration of an adsorption tower throughout a year.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment (in the case of an internal boosting type) of a cryogenic air separation device according to the present invention.
FIG. 2 is a diagram showing an example of temperature behavior per cycle of regeneration tower outlet temperature of regeneration gas in the TSA adsorption tower regeneration step according to the present invention.
FIG. 3 is a diagram for explaining an embodiment of a control flow of self-optimal control in the TSA adsorption tower regeneration step according to the present invention.
FIG. 4 is a diagram for explaining an embodiment of self-optimal control of a TSA adsorption tower regeneration process according to the present invention.
FIG. 5 is a diagram for explaining an embodiment of self-optimal control of a TSA adsorption tower regeneration process according to the present invention.
FIG. 6 is a diagram for explaining another embodiment of the self-optimal control of the TSA adsorption tower regeneration process according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Raw material air compressor, 2 ... Cooling tower (washing cooling tower), 3 ... Adsorption tower, 5 ... Cold box (cold storage tank), 6 ... Expansion turbine, 7 ... Rectification tower (upper tower), 8 ... Rectification Tower (lower tower), 9 ... Liquid oxygen drum, 10 ... Liquid oxygen pump, 11 ... Regenerative gas heater (external heating source), 12 ... Subcooler, 13 ... Air heat exchanger, 14 ... Evaporator, 18 ... Regeneration gas flow control valve, 19 ... gas line, 20 ... evaporative cooling tower, 23 ... evaporative cooling tower gas line, 24 ... evaporative cooling tower activation bypass, 26 ... adsorption tower activation bypass, 29 ... regeneration gas line (inlet), DESCRIPTION OF SYMBOLS 30 ... DCS control computer, 31 ... Input means, 32 ... Display apparatus, 33 ... Memory | storage device, 35, 36 ... Temperature measuring instrument TI, 42 ... Product oxygen gas line, 51, 52 ... Line.

Claims (5)

原料空気圧縮機にて大気から圧縮され、ＴＳＡ方式の吸着塔を含む前処理装置において前処理された空気を原料とし、該原料の空気からコールドボックスにおいて深冷分離法にて主に窒素又は酸素を分離連続生産する深冷空気分離装置であって、
前記ＴＳＡ方式の吸着塔への再生サイクルにおいて前記吸着塔への再生条件が適正であるか否かを自己判断し、該自己判断された結果適正でない場合には自動でその後の前記吸着塔への再生条件を制御して是正する機能を有するＤＣＳ制御計算機を備えたことを特徴とする深冷空気分離装置。Air is compressed from the atmosphere with a raw material air compressor and pretreated in a pretreatment device including a TSA type adsorption tower as raw material, and nitrogen or oxygen is mainly separated from the raw material air in a cold box by a cryogenic separation method. A cryogenic air separation device for continuous production of
In the regeneration cycle to the TSA type adsorption tower, it is self-determined whether or not the regeneration conditions for the adsorption tower are appropriate, and if the self-determined result is not appropriate, it is automatically transferred to the subsequent adsorption tower. A cryogenic air separation device comprising a DCS control computer having a function of controlling and correcting a regeneration condition. 前記ＤＣＳ制御計算機において、前記吸着塔への再生条件が適正であるか否かの自己判断を、前記吸着塔の再生ガス出口温度または前記吸着塔の入口空気温度の挙動変化の監視の基に行うことを特徴とする請求項１記載の深冷空気分離装置。In the DCS control computer, the self-judgment as to whether or not the regeneration condition for the adsorption tower is appropriate is made based on monitoring the behavior change of the regeneration gas outlet temperature of the adsorption tower or the inlet air temperature of the adsorption tower. The cryogenic air separation device according to claim 1. 前記ＤＣＳ制御計算機において、前記吸着塔への再生条件の制御として、前記吸着塔へ導入する再生ガス温度または再生ガス量の制御であることを特徴とする請求項１記載の深冷空気分離装置。2. The chilled air separation apparatus according to claim 1, wherein in the DCS control computer, the regeneration condition to the adsorption tower is controlled by controlling the regeneration gas temperature or the regeneration gas amount introduced into the adsorption tower. 原料空気圧縮機にて大気から圧縮され、ＴＳＡ方式の吸着塔を含む前処理装置において前処理された空気を原料とし、該原料の空気からコールドボックスにおいて深冷分離法にて主に窒素又は酸素を分離連続生産する深冷空気分離装置であって、
前記ＴＳＡ方式の吸着塔の再生ガス出口温度または前記吸着塔の入口空気温度の挙動変化を監視し、前記吸着塔への再生サイクルにおいて前記監視された前記再生ガス出口温度または前記入口空気温度の挙動変化が適正範囲にあるか否かを自己判断し、該自己判断された結果前記再生ガス出口温度または前記入口空気温度の挙動変化が適正範囲からはずれた場合には自動でその後の前記吸着塔へ導入する再生ガス温度または再生ガス量を制御して是正する機能を有するＤＣＳ制御計算機を備えたことを特徴とする深冷空気分離装置。Air is compressed from the atmosphere with a raw material air compressor and pretreated in a pretreatment device including a TSA type adsorption tower as raw material, and nitrogen or oxygen is mainly separated from the raw material air in a cold box by a cryogenic separation method. A cryogenic air separation device for continuous production of
Changes in the behavior of the regeneration gas outlet temperature of the TSA type adsorption tower or the inlet air temperature of the adsorption tower are monitored, and the behavior of the monitored regeneration gas outlet temperature or the inlet air temperature in the regeneration cycle to the adsorption tower is monitored. Self-determining whether or not the change is in an appropriate range, and if the change in behavior of the regeneration gas outlet temperature or the inlet air temperature deviates from the appropriate range as a result of the self-determination, it automatically goes to the subsequent adsorption tower A chilled air separation device comprising a DCS control computer having a function of controlling and correcting a regenerative gas temperature or a regenerative gas amount to be introduced. 前記ＤＣＳ制御計算機において、さらに、前記吸着塔において異常兆候が表れたときに、このまま持続した場合の運転可能日数を内部関数で発生させて通知する機能を有することを特徴とした請求項１または４記載の深冷空気分離装置。5. The DCS control computer further has a function of generating and notifying an internal function of the number of days that can be operated when an abnormality sign appears in the adsorption tower when the adsorption tower continues. The cryogenic air separation device as described.
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Cited By (8)

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JP2006258302A (en) * 2005-03-15 2006-09-28 Taiyo Nippon Sanso Corp Purification method for raw material air in air liquefaction separation device
CN102240495A (en) * 2010-05-12 2011-11-16 林德股份公司 Adsorption device
KR101225380B1 (en) * 2005-12-23 2013-01-24 재단법인 포항산업과학연구원 A monitoring device for intercooler of a compressor and a control method thereof
JP2014223622A (en) * 2013-05-16 2014-12-04 エア プロダクツ アンド ケミカルズ インコーポレイテッドＡｉｒ Ｐｒｏｄｕｃｔｓ Ａｎｄ Ｃｈｅｍｉｃａｌｓ Ｉｎｃｏｒｐｏｒａｔｅｄ Purification of air
JP2015094475A (en) * 2013-11-08 2015-05-18 株式会社カワタ Dryer
KR20190078223A (en) * 2017-12-26 2019-07-04 주식회사 포스코 Apparatus for controling heat capacity of by-product gas in complex generating system
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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006258302A (en) * 2005-03-15 2006-09-28 Taiyo Nippon Sanso Corp Purification method for raw material air in air liquefaction separation device
JP4590287B2 (en) * 2005-03-15 2010-12-01 大陽日酸株式会社 Purification method of raw material air in air liquefaction separation device
KR101225380B1 (en) * 2005-12-23 2013-01-24 재단법인 포항산업과학연구원 A monitoring device for intercooler of a compressor and a control method thereof
CN102240495A (en) * 2010-05-12 2011-11-16 林德股份公司 Adsorption device
JP2014223622A (en) * 2013-05-16 2014-12-04 エア プロダクツ アンド ケミカルズ インコーポレイテッドＡｉｒ Ｐｒｏｄｕｃｔｓ Ａｎｄ Ｃｈｅｍｉｃａｌｓ Ｉｎｃｏｒｐｏｒａｔｅｄ Purification of air
US9108145B2 (en) 2013-05-16 2015-08-18 Air Products And Chemicals, Inc. Purification of air
JP2015094475A (en) * 2013-11-08 2015-05-18 株式会社カワタ Dryer
KR20190078223A (en) * 2017-12-26 2019-07-04 주식회사 포스코 Apparatus for controling heat capacity of by-product gas in complex generating system
KR102015513B1 (en) * 2017-12-26 2019-08-28 주식회사 포스코 Apparatus for controling heat capacity of by-product gas in complex generating system
CN111971107A (en) * 2018-03-09 2020-11-20 奥图工业有限公司 System, device and method for separating oxygen from air
WO2024024572A1 (en) * 2022-07-26 2024-02-01 国立研究開発法人物質・材料研究機構 Co2 separation system

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