JP2004099718A - Method and apparatus for making lng having high calorific value have low calorie - Google Patents

Method and apparatus for making lng having high calorific value have low calorie Download PDF

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JP2004099718A
JP2004099718A JP2002262560A JP2002262560A JP2004099718A JP 2004099718 A JP2004099718 A JP 2004099718A JP 2002262560 A JP2002262560 A JP 2002262560A JP 2002262560 A JP2002262560 A JP 2002262560A JP 2004099718 A JP2004099718 A JP 2004099718A
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gas
lng
separated
liquid
calorific value
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JP4194325B2 (en
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Makoto Ozaki
尾崎　誠
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Ishikawajima Plant Construction Co Ltd
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Ishikawajima Plant Construction Co Ltd
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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
    • F25J3/0204—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 characterised by the feed stream
    • F25J3/0209—Natural gas or substitute natural gas
    • F25J3/0214—Liquefied natural gas
    • 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
    • F25J3/0228—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 characterised by the separated product stream
    • F25J3/0233—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 characterised by the separated product stream separation of CnHm with 1 carbon atom or more
    • 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
    • F25J3/0295—Start-up or control of the process; Details of the apparatus used, e.g. sieve plates, packings
    • 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
    • F25J2200/02—Processes or apparatus using separation by rectification in a single pressure main column system
    • 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
    • F25J2200/74—Refluxing the column with at least a part of the partially condensed overhead gas
    • 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
    • F25J2205/02—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum
    • F25J2205/04—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum in the feed line, i.e. upstream of the fractionation step
    • 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
    • F25J2205/90—Mixing of components
    • 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
    • F25J2210/00—Processes characterised by the type or other details of the feed stream
    • F25J2210/06—Splitting of the feed stream, e.g. for treating or cooling in different ways
    • 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
    • F25J2280/00—Control of the process or apparatus
    • F25J2280/02—Control in general, load changes, different modes ("runs"), measurements

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for making an LNG having a high calorific value have low calories, with which the calorific value of the LNG is readily and inexpensively adjusted without deteriorating the combustion characteristic of the LNG and the LNG is shipped. <P>SOLUTION: In adjusting the LNG, which is concentrated in a low-temperature storage tank 11 and made into a heavy LNG, to a gas having a fixed calorific value and supplying the gas to a consumption system, the LNG discharged from the low-temperature storage tank 11 is heated and vaporized, the vaporized gas is mixed with the LNG discharged from the low-temperature storage tank 11, the temperature of the mixture is adjusted, the gas and the liquid are equilibrated, introduced into a gas-liquid separator 14, separated into a gas and a liquid under fixed pressure, the heavy separated liquid subjected to the gas-liquid separation is introduced to a distillation column 31, the heavy component is separated from the separated liquid, a light component is gasified, the gas of the gasified light component is mixed with the gas separated by the gas-liquid separator 14 and supplied to the consumption system. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、ＬＮＧ貯蔵基地等からＬＮＧを都市ガスとして供給するための高発熱量ＬＮＧの低カロリー化方法及びその装置に関するものである。
【０００２】
【従来の技術】
ＬＮＧの貯蔵基地で、ＬＮＧを長期間貯蔵すると、タンク及び付帯設備に低温で滞留しているＬＮＧへの外気、付属ポンプ等からの入熱により、メタンを主成分としたガス（ＢＯＧ）が蒸発する。
【０００３】
ＬＮＧは、メタンを主成分とした、エタン、プロパン、ブタンなどの重質分との混合成分であるために、ＬＮＧの大部分を占める低沸点成分であるメタンが優先的に蒸発する。ＢＯＧは、自圧或いは圧縮機で昇圧して消費者に供給するが、ＢＯＧ量が多く（貯蔵量大）消費量が少ないケースでは、メタン成分がＢＯＧとして多く失われるために残留液は重質化し、高発熱量のＬＮＧとなる。
【０００４】
輸入されるＬＮＧ或いはこれらの基地からサテライト基地等に入るＬＮＧは、殆どの場合、都市ガス（１３Ａ）の発熱量４６．０５ＭＪ／Ｎｍ３　（１１０００ｋｃａｌ／Ｎｍ３　）より低い。しかし、貯蔵は低温度であるため、タンクへの外気等からの入熱により、メタンを主成分とした低沸点の軽質成分が先に蒸発して失われ、残液が重質化（高発熱量）する。
【０００５】
このような重質化は貯蔵基地に入荷するＬＮＧが１３Ａガスの規制値に近い場合は、容易に発熱量が規制値を超える。また、貯蔵基地のＢＯＧ量が多く年間の貯蔵液量から年間のＢＯＧ発生量を引いた貯蔵液の収斂組成が、発熱量の規制値を超える場合はＬＮＧからの気化ガスから重質分を除去しなければならない。また、入荷液が当初から規制値を超える場合は当然入荷ＬＮＧから重質分を除去しなければならない。
【０００６】
ＬＮＧ貯蔵基地において重質化した気化ガスの単位体積当たりの発熱量は高くなり、都市ガスで規制されている発熱量を超えるために、濃縮ＬＮＧの気化ガスを低発熱量に調整する装置が必要になる。
【０００７】
従来、単位体積当たりの高発熱量ガスを低発熱量に調整する方法としては、水素ガスで希釈する方法、空気で希釈する方法、ＢＯＧを再液化して貯蔵タンクに戻す方法などが考えられる。
【０００８】
【特許文献１】
特開２００２−３８１７０号公報
【０００９】
【発明が解決しようとする課題】
しかしながら、これらの方法は以下の問題がある。
【００１０】
（ａ）水素ガスで希釈する方法
この方法は燃焼性等の点から優れた方法であるが、水素ガスを得るのが難しいので、その点に難点がある。水素ガス製造装置を作ると設備費或いは運転費が高くなり経済性が悪くなる。運転、維持等が面倒になる。
【００１１】
（ｂ）空気で希釈する方法
この方法は空気を圧縮して必要量を混合すれば、容易に所定の発熱量の都市ガスが得られるので経済的に優れた方法であるが、重質成分の含有量によっては燃焼特性が悪くなるために混合量が制限される。従って、十分な熱調設備とは言えない。
【００１２】
（ｃ）ＢＯＧの再液化方法
ＢＯＧを再液化して貯蔵タンクに返せば貯蔵液は濃縮しない。再液化方法には冷凍機或いは出荷するＬＮＧの冷熱でＢＯＧを凝縮させる方法があるが、冷凍機での再液化は設備費及び運転費が高価になるので経済性が劣る。
【００１３】
出荷ＬＮＧで冷却してＢＯＧを再液化する設備は冷凍機設備より経済性が優れているが、ＢＯＧの量が多くＬＮＧの出荷量が少ない場合は、出荷ＬＮＧの量では、必要なＢＯＧを液化できない場合があり濃縮の問題を解決できないケースがある。
【００１４】
そこで、本発明の目的は、上記課題を解決し、ＬＮＧの燃焼特性を劣化させることなく容易にかつ安価に発熱量を調整して出荷できる高発熱量ＬＮＧの低カロリー化方法を提供することにある。
【００１５】
【課題を解決するための手段】
上記目的を達成するために請求項１の発明は、低温貯蔵タンク内で濃縮されて重質化したＬＮＧを所定の発熱量のガスに調整して消費系に供給するに際し、低温貯蔵タンクから払い出されるＬＮＧを加熱して気化し、その気化ガスと低温貯蔵タンクから払い出されるＬＮＧとを混合してその温度を調整し、気液を平衡させた後、これを気液分離器に導入して一定圧力下で気液分離し、その気液分離された重質の分離液を蒸留塔に導入して分離液から重質成分を分離すると共に軽質成分をガス化させ、そのガス化した軽質成分のガスを気液分離器で分離されたガスに混入して消費系に供給するようにした高発熱量ＬＮＧの低カロリー化方法である。
【００１６】
請求項２の発明は、気液分離器で分離されたガスの温度を検出し、その温度が設定温度となるよう、上記気化ガスとＬＮＧの混合量を制御する請求項１記載の高発熱量ＬＮＧの低カロリー化方法である。
【００１７】
請求項３の発明は、蒸留塔に導入した分離液を加熱してメタン、エタンからなる軽質成分とプロパン、ブタンからなる重質成分とに分離し、その軽質成分のガスを、気液分離器で分離されたガスに混入する請求項１又は２記載の高発熱量ＬＮＧの低カロリー化方法である。
【００１８】
請求項４の発明は、低温貯蔵タンク内で濃縮されて重質化したＬＮＧを所定の発熱量のガスに調整して消費系に供給するための高発熱量ＬＮＧの低カロリー化装置において、低温貯蔵タンク内の重質化したＬＮＧを払い出す払出ラインと、その払出ラインに接続された気化器と、気化器をバイパスするＬＮＧラインと、払出ラインに接続され、気化器で気化された気化ガスとＬＮＧラインからのＬＮＧを混合する第１ラインミキサーと、払出ラインに接続され、ラインミキサーで混合されたＬＮＧを導入し、これを気液分離する気液分離器と、気液分離器の頂部に接続され、分離された軽質成分のガスを消費系に供給するためのガスラインと、気液分離器で、分離された分離液を導入してこれを蒸留分離する蒸留塔と、蒸留塔で蒸留分離された軽質成分を上記ガスラインのガスに混入する蒸留ガスライとを備えた高発熱量ＬＮＧの低カロリー化装置である。
【００１９】
【発明の実施の形態】
以下、本発明の好適な一実施形態を添付図面に基づいて詳述する。
【００２０】
図１において、１０は、低温貯蔵タンク１１と払出ポンプ１２から構成されるＬＮＧ設備で、そのＬＮＧ払出ライン１３に気液分離器１４が接続される。
【００２１】
気液分離器１４に至るＬＮＧ払出ライン１３には、第１圧力調整弁１５、第１開閉弁１６、気化器１７、第１ラインミキサー１８が順次接続される。
【００２２】
気液分離器１４の頂部には、ガスライン１９が接続され、そのガスライン１９に、第２圧力調整弁２０、第２開閉弁２１、ガス加熱器２２、流量計２３、閉止弁２５、第３圧力調整弁２６が順次接続される。
【００２３】
閉止弁２５の前後のガスライン１９には、導入ライン２７と排出ライン２８を介してバッファタンク３０が接続される。導入ライン２７には、導入弁２９ａが、排出ライン２８には、排出弁２９ｂが接続される。
【００２４】
気液分離器１４の底部には、気液分離後の液を蒸留塔３１に供給する液ライン３２が接続される。この液ライン３２には、液位調整弁３３、流量計３４、液導入弁３５が接続される。
【００２５】
蒸留塔３１は、その塔体３６の下部にボトム加熱器３７が設けられ、その上部に下段蒸留部３８と上段蒸留部３９が設けられ、蒸留塔頂部にコンデンサー４０が設けられる。
【００２６】
液ライン３２は、下段蒸留部３８と上段蒸留部３９の間の塔体３６に接続される。
【００２７】
塔体３６の頂部には蒸留ガスライン４１が接続され、その蒸留ガスライン４１が、第２圧力調整弁２０と第２開閉弁２１間のガスライン１９に接続される。このガスライン１９に至る蒸留ガスライン４１には、第２圧力調節器４２と第３圧力調整弁４３が接続される。第３圧力調整弁４３は、第２圧力調節器４２により制御される。
【００２８】
塔体３６の底部には、ＬＰＧ排出ライン４４が接続され、そのＬＰＧ排出ライン４４に、液位調節弁４５、ＬＰＧ冷却器４６が接続される。液位調節弁４５は、蒸留塔３１に設けた第２液面調節計４７により制御される。
【００２９】
払出ポンプ１２の吐出側の払出ライン１３には、第１圧力調整弁１５をバイパスして、低温貯蔵タンク１１のＬＮＧをコンデンサー４０に流した後、第１圧力調整弁１５の下流側に戻すバイパスライン４８が接続され、その入口側バイパスライン４８ａに、蒸留塔３１の頂部に設けた温度調節器４９に応じてＬＮＧ量を調整する温度調整弁５０が接続される。
【００３０】
また、入口側バイパスライン４８ａの下流側の払出ライン１３には、第１圧力調整弁１５、第１開閉弁１６、気化器１７をバイパスして第１ラインミキサー１８にＬＮＧを流すＬＮＧライン５１が接続され、そのＬＮＧライン５１に温度調整弁５２が接続される。
【００３１】
気化器１７の出口側の払出ライン１３には、気化ガスを定期的に分析する成分分析計５３が接続され、その分析値が制御器５４に入力される。また気液分離器１４の頂部には温度調節器５５が設けられ、その検出値が制御器５４に入力される。
【００３２】
また、ガス加熱器２２の出口側のガスライン１９には圧力調節器５６が接続され、この圧力調節器５６の検出値が設定圧となるように払出ライン１３の第１圧力調整弁１５が制御されるようになっている。
【００３３】
さらにガスライン１９には、発熱量分析器５７が接続され、この発熱量分析器５７で分析された発熱量が温度調節器５５を介して制御器５４に入力され、発熱量分析器５７で分析された発熱量が規制値（１３Ａ）となるように制御器５４が温度調節器５５の設定温度を設定するようになっている。
【００３４】
気液分離器１４には、分離した分離液の液面を検出する液面計５８が設けられ、この液面計５８の検出値が制御器５９に入力される。制御器５９には、ガスライン１９に接続した流量計２３の流量値と、液ライン３２に接続した流量計３４の流量値とが入力される。制御器５９は、これら流量値と液面計５８の検出値に応じて液位調整弁３３を制御するようになっている。
【００３５】
ボトム加熱器３７の加熱媒体供給ライン３７ａには、流量制御弁６０が接続される。蒸留塔３１の下部には温度制御器６１が設けられ、この検出値が制御器６２に入力される。制御器６２は、温度制御器６１からの検出値と流量計３４から入力される流量値に応じて流量制御弁６０を制御するようになっている。
【００３６】
次に、本発明の高発熱量ＬＮＧの低カロリー化方法を説明する。
【００３７】
低温貯蔵タンク１１内で濃縮されたＬＮＧは払出ポンプ１２で加圧されて、ガスライン１９の圧力調整器５６の圧力が所定圧力になるように第１圧力調節弁１５で制御されて第１気化器１７に入る。
【００３８】
気化器１７でＬＮＧは海水、空気、その他の加熱媒体で加熱されて、約０℃以上の気化ガスになる。
【００３９】
気化ガスは定期的に成分分析器５３で分析されて組成を確定する。その後第１ラインミキサー１８に入る。
【００４０】
第１ラインミキサー１８には第１圧力調節弁１５の上流から分岐されたＬＮＧライン５１を通して、温度調整弁５２で、その流量が調節されたＬＮＧが流入する。第１ラインミキサー１８に入った気化ガスとＬＮＧとは、両流体が均一になるように十分に混合される。
【００４１】
ＬＮＧライン５１の温度調節弁５２は、下流側の気液分離器１４に設置されている温度調節器５５により、温度が所定温度になるように制御器５４で制御されて、第１ラインミキサー１８での気化ガスとＬＮＧの混合量が制御されてＬＮＧが流入する。
【００４２】
温度調節器５５の設定温度は、成分分析器５３の分析結果から定期的に決められる。温度調節器５５の設定温度は、例えば圧力が０．６ＭＰａの場合に約−６０℃前後（気・液平衡計算から求める）になる。
【００４３】
第１ラインミキサー１８に入った気化ガスとＬＮＧは、第１ラインミキサー１８内で両流体が均一になるように十分に混合される。
【００４４】
混合流体は気液分離器１４に入り比重差でガスと液に分離される。気液分離器１４内の圧力は、気液平衡状態から算出される必要圧力に、ガスライン１９に設置された第２圧力調整弁２０により一定に調整される。分離されたガスは低発熱量の軽質成分で、分離液は高発熱量の重質成分となる。
【００４５】
第２圧力調整弁２０から流出したガスは低温なのでガス加熱器２２に入り０℃以上に海水、空気、その他の加熱媒体により加熱される。
【００４６】
ガス加熱器２２からの流出ガスは、圧力調整器５６の圧力が所定圧力になるように第１圧力調節弁１５により調節され、流量が流量計２３で測定され、バッファタンク３０に溜められた後、第３圧力調整弁２６を介して消費系に供給される。
【００４７】
バッファタンク３０は、基地外へのガス供給が激しく変動する場合のシステムの圧力変動を緩やかにするために設置する。第３圧力調整弁２６は下流側の圧力を必要な圧力に維持するために設けられる。
【００４８】
気液分離器１４で分離されたガスとの平衡液（分離液）は気液分離器１４の底部に貯蔵され、余剰液は底部から液ライン３２を介して蒸留塔３１に送られる。
【００４９】
気液分離器１４から蒸留塔３１に送られる余剰分離液は、液面計５８と液位調整弁３３により制御されると同時に流量計３４により、蒸留塔３１への流量を一定時間（θ）の間一定流量で流れるように制御される。これは、流量が短時間で大きく変動すると塔頂・塔底のプロダクトの性質が安定しないのでこのような制御を行なう。このために、気液分離器１４の底部の分離液貯蔵体積を、分離量の数時間分以上溜められるようにする。
【００５０】
制御器５９は、流量計２３と第２液面調節計４７から蒸留塔３１での妥当な処理量を定期的に算定し、算定値を流量計３４に伝送して液位調整弁３３で流量制御することにより、蒸留塔３１に適切な処理量を送り込む。
【００５１】
蒸留塔３１に送られた分離液はエタン以上の軽沸点成分とＬＰＧに分離される。軽沸点成分は塔頂からガスとして、ＬＰＧは塔底から液状でそれぞれ分離される。
【００５２】
塔頂ガスは蒸留ガスライン４１より、気液分離器１４からの分離ガスに混入して都市ガスの原料とするが、低温度なのでガス加熱器２２の入口で気液分離器１４の分離ガスと合流する。
【００５３】
蒸留塔３１内に導入された気液分離器１４からの分離液は、塔底に設置されているボトム加熱器３７で加熱され蒸発し、塔頂ではコンデンサー４０で、バイパスライン４８からのＬＮＧを冷却媒体として冷却される。
【００５４】
この蒸留塔３１の分離のためのキー成分は、塔頂ではプロパン成分で、塔底ではエタン成分となる。
【００５５】
塔頂、塔底温度は定期的に原料ＬＮＧの組成を確認している成分分析計５３から、塔頂と塔底のキー成分の許容含有量を算定して、蒸留塔３１の圧力に対応した温度になるように加熱媒体或は冷却媒体の流量を制御する。
【００５６】
塔底のボトム加熱器３７は温度調節器４９と成分分析計５３から決められた温度になるように、温度制御器６１と温度制御弁６０により加熱流体が制御される。同時に気液分離器１４の分離液の流入量を測定している流量計３４のデータにより、蒸留塔３１の塔底での必要加熱量を確保するように熱媒体の流量を流量制御弁６０で制御する。
【００５７】
塔頂温度は決められた温度になるように温度調節器４９と温度調整弁５０によりＬＮＧ量を制御する。
【００５８】
塔頂コンデンサー４０の冷却温度は通常低い温度となるので、冷却媒体はＬＮＧの顕熱を使用することになる。従って、ＬＮＧは第１圧力調節弁１５の上流側からコンデンサー４０に導き、下流側に返して気化器１７で気化させてガスの製造に供する。
【００５９】
塔頂ガスは塔内圧力調節器４２と圧力調節弁４３により、所定の圧力を維持するように塔内から排出され、圧力調節弁２０の下流側で、ガス加熱器２２の入口より上流で気液分離器１４の分離ガスに混入される。
【００６０】
塔底のＬＰＧは設定液面より高くなると、液面調節計４７と液面調節弁４５より塔外に排出される。ＬＰＧは冷却器４６で常温に冷却されてＬＰＧタンクに送られ、貯蔵されると共に熱調の原料或は他の用途に供する。
【００６１】
次に、より具体的な実施例を説明する。
【００６２】
（１）発熱量が４６．０５ＭＪ／Ｎｍ３　（１１０００ｋｃａｌ／Ｎｍ３　）以上になったＬＮＧの組成の一例として、下記の例について実施例を説明する。
【００６３】

Figure 2004099718
上記のＬＮＧ組成中のＣ２（エタン）、Ｃ３（プロパン）、Ｃ４（ブタン），Ｃ５（ペンタン）の含有量は僅かであるが、メタンに比べて発熱量が約２〜３倍以上あり、これが都市ガスの発熱量４６．０５ＭＪ／Ｎｍ３　（１１０００ｋｃａｌ／Ｎｍ３　）以上とする要因である。
【００６４】
（２）（１）のガスの気液分離器１４における気液平衡関係からガスと液の組成を求める。それぞれの概略の分離量と発熱量は次のようになる。
【００６５】
Figure 2004099718
（３）気液分離器１４での熱的条件を作る為にラインミキサー１８で、気化器１７での気化ガス量と冷却ＬＮＧ量を求める。
【００６６】
Figure 2004099718
（４）上記の平衡計算をべースにして実際に都市ガス（１３Ａ）を製造する場合のマテリアルバランスについて一例を示す。
【００６７】
Figure 2004099718
このように本発明は（５）に示した各流量を各ユニット毎に設定された圧力と温度条件下で制御し、所定の発熱量のガスを製造するものである。
【００６８】
ＬＮＧの組成が変動しない場合の気液分離器１４での分離は、圧力と温度を正確に制御すれば、理論上は所定の発熱量のガス（１３Ａ）を得ることが可能であるが、都市ガスの消費量が常に変動するので、実際には正確な温度（検知遅れ等）とそれに対する流量の制御が難しい。
【００６９】
この理由で本発明では、気液分離器１４での分離ガスの発熱量が規定値（１３Ａ）よりも低めになるように、設定圧力に対する温度の制御値を設定する。気液分離器１４の分離ガスを規定値（１３Ａ）にする為の微調整は、下流に設置されている常設の熱調設備により行なう。この場合、蒸留塔３１で分離回収したＬＰＧ排出ライン４４からのＬＰＧを分離ガスに混入して熱調する。
【００７０】
【発明の効果】
以上要するに本発明によれば、重質化したＬＮＧを気液分離器で気液分離し、その気液分離した分離液を蒸留塔で蒸留してプロパンなどの重質成分を除去し、軽質成分を気液分離器で分離されたガスに混入して消費系に供給することで、燃料特性を劣化させることなく容易にかつ安価に発熱量を調整することができる。
【図面の簡単な説明】
【図１】本発明の一実施の形態を示す図である。
【符号の説明】
１１　低温貯蔵タンク
１３　払出ライン
１４　気液分離器
１９　ガスライン
３１　蒸留塔[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for reducing the calorific value of a high calorific value LNG for supplying LNG as city gas from an LNG storage base or the like.
[0002]
[Prior art]
When LNG is stored at an LNG storage base for a long period of time, gas (BOG) containing methane as a main component evaporates due to heat input from outside air and attached pumps to LNG that is staying at low temperature in tanks and auxiliary equipment at low temperatures. I do.
[0003]
LNG is a mixed component with heavy components such as ethane, propane, and butane containing methane as a main component. Therefore, methane, which is a low-boiling component that occupies most of LNG, evaporates preferentially. BOG is supplied to the consumer by increasing its pressure by a self-pressure or a compressor. In the case of a large amount of BOG (large storage amount) and a small amount of consumption, a large amount of methane is lost as BOG, so the residual liquid is heavy. And LNG having a high calorific value is obtained.
[0004]
In most cases, LNG to be imported or LNG entering a satellite base or the like from these bases is lower than the calorific value of city gas (13A) of 46.05 MJ / Nm 3 (11000 kcal / Nm 3 ). However, since the storage is at a low temperature, low-boiling light components mainly composed of methane are first evaporated and lost due to heat input from the outside air to the tank, and the remaining liquid becomes heavy (high heat generation). Amount).
[0005]
Such heavierness easily causes the calorific value to exceed the regulation value when the LNG received at the storage base is close to the regulation value of 13A gas. Also, if the amount of BOG at the storage base is large and the astringent composition of the storage solution obtained by subtracting the annual BOG generation amount from the annual storage solution amount exceeds the regulation value of the calorific value, heavy components are removed from the vaporized gas from LNG. Must. Also, if the received liquid exceeds the regulation value from the beginning, naturally heavy substances must be removed from the received LNG.
[0006]
Since the calorific value per unit volume of the heavy gas at the LNG storage base increases and exceeds the calorific value regulated by city gas, a device that adjusts the calorific value of the concentrated LNG to a low calorific value is required. become.
[0007]
Conventionally, as a method of adjusting a high calorific value gas per unit volume to a low calorific value, a method of diluting with hydrogen gas, a method of diluting with air, a method of reliquefying BOG and returning it to a storage tank, and the like can be considered.
[0008]
[Patent Document 1]
JP-A-2002-38170
[Problems to be solved by the invention]
However, these methods have the following problems.
[0010]
(A) Method of diluting with hydrogen gas This method is excellent in terms of flammability and the like, but it is difficult to obtain hydrogen gas, so there is a drawback in that point. When a hydrogen gas production apparatus is manufactured, equipment costs or operation costs increase, and economic efficiency deteriorates. Driving and maintenance are troublesome.
[0011]
(B) Method of diluting with air This method is economically excellent because if a required amount of city gas is easily obtained by compressing air and mixing the required amount, this method is economically excellent, Depending on the content, the combustion characteristics deteriorate, so the mixing amount is limited. Therefore, it cannot be said that it is a sufficient heat control facility.
[0012]
(C) Reliquefaction method of BOG If the BOG is reliquefied and returned to the storage tank, the storage liquid will not be concentrated. As a reliquefaction method, there is a method in which BOG is condensed by the cold of a refrigerator or LNG to be shipped. However, the reliquefaction in a refrigerator has a high equipment cost and an operation cost, and is therefore less economical.
[0013]
Equipment that cools and re-liquefies BOG by shipping LNG is more economical than refrigerator equipment, but when the amount of BOG is large and the amount of LNG shipped is small, the required BOG is liquefied with the amount of shipped LNG. In some cases, the problem of enrichment cannot be solved.
[0014]
Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a method for reducing the calorific value of a high calorific value LNG which can be easily and inexpensively adjusted in calorific value without deteriorating the combustion characteristics of the LNG and shipped. is there.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 adjusts LNG concentrated and heavy in a low-temperature storage tank to a gas having a predetermined calorific value and supplies the gas to a consumption system. The heated LNG is vaporized by heating, the vaporized gas is mixed with LNG discharged from the low-temperature storage tank, the temperature is adjusted, and the gas and liquid are equilibrated. Gas-liquid separation under pressure, the gas-liquid separated heavy separated liquid is introduced into a distillation column to separate heavy components from the separated liquid and gasify light components, and the gasified light components This is a method of reducing the calorie of the high calorific value LNG in which the gas is mixed into the gas separated by the gas-liquid separator and supplied to the consumption system.
[0016]
The invention according to claim 2 detects the temperature of the gas separated by the gas-liquid separator and controls the mixture amount of the vaporized gas and LNG so that the temperature becomes a set temperature. This is a method for reducing the calories of LNG.
[0017]
According to a third aspect of the present invention, the separated liquid introduced into the distillation column is heated and separated into a light component composed of methane and ethane and a heavy component composed of propane and butane, and the gas of the light component is separated into a gas-liquid separator. 3. The method for reducing calorie of a high calorific value LNG according to claim 1 or 2, wherein the calorific value is mixed with the gas separated in step (a).
[0018]
The invention according to claim 4 is a high calorific value LNG calorie reducing apparatus for adjusting LNG concentrated and heavy in a low temperature storage tank to a gas having a predetermined calorific value and supplying the gas to a consuming system. A discharge line for discharging heavy LNG in the storage tank, a vaporizer connected to the discharge line, an LNG line bypassing the vaporizer, and a vaporized gas connected to the discharge line and vaporized by the vaporizer. A first line mixer for mixing LNG from the LNG line, a LNG connected to the discharge line, introducing the LNG mixed by the line mixer, and separating the LNG into gas and liquid, and a top of the gas and liquid separator A gas line for supplying the gas of the separated light component to the consumption system, a gas-liquid separator, a distillation column for introducing the separated liquid and distilling and separating the separated liquid, and a distillation column. Distilled and separated The light component is a low calorie apparatus having high heating value LNG having a distillation Gasurai mixed in the gas of the gas line.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0020]
In FIG. 1, reference numeral 10 denotes an LNG facility including a low-temperature storage tank 11 and a discharge pump 12, and a gas-liquid separator 14 is connected to the LNG discharge line 13.
[0021]
A first pressure regulating valve 15, a first on-off valve 16, a vaporizer 17, and a first line mixer 18 are sequentially connected to the LNG discharge line 13 leading to the gas-liquid separator 14.
[0022]
A gas line 19 is connected to the top of the gas-liquid separator 14, and the gas line 19 is connected to a second pressure regulating valve 20, a second on-off valve 21, a gas heater 22, a flow meter 23, a shutoff valve 25, The three pressure adjusting valves 26 are sequentially connected.
[0023]
A buffer tank 30 is connected to a gas line 19 before and after the shutoff valve 25 via an introduction line 27 and a discharge line 28. An introduction valve 29a is connected to the introduction line 27, and a discharge valve 29b is connected to the discharge line 28.
[0024]
A liquid line 32 for supplying the liquid after gas-liquid separation to the distillation column 31 is connected to the bottom of the gas-liquid separator 14. A liquid level adjusting valve 33, a flow meter 34, and a liquid introduction valve 35 are connected to the liquid line 32.
[0025]
The distillation tower 31 is provided with a bottom heater 37 below the tower body 36, a lower distillation section 38 and an upper distillation section 39 above, and a condenser 40 at the top of the distillation tower.
[0026]
The liquid line 32 is connected to a tower 36 between a lower distillation section 38 and an upper distillation section 39.
[0027]
A distillation gas line 41 is connected to the top of the tower 36, and the distillation gas line 41 is connected to the gas line 19 between the second pressure regulating valve 20 and the second on-off valve 21. A second pressure regulator 42 and a third pressure regulating valve 43 are connected to a distillation gas line 41 leading to the gas line 19. The third pressure regulating valve 43 is controlled by the second pressure regulator 42.
[0028]
An LPG discharge line 44 is connected to the bottom of the tower 36, and a liquid level control valve 45 and an LPG cooler 46 are connected to the LPG discharge line 44. The liquid level control valve 45 is controlled by a second liquid level controller 47 provided in the distillation column 31.
[0029]
In the discharge line 13 on the discharge side of the discharge pump 12, the LNG of the low-temperature storage tank 11 is caused to flow through the condenser 40 by bypassing the first pressure regulating valve 15, and then returned to the downstream side of the first pressure regulating valve 15. The line 48 is connected, and a temperature control valve 50 for adjusting the LNG amount according to a temperature controller 49 provided at the top of the distillation column 31 is connected to the inlet side bypass line 48a.
[0030]
Further, an LNG line 51 for flowing LNG to the first line mixer 18 by bypassing the first pressure regulating valve 15, the first on-off valve 16, and the carburetor 17 is provided in the discharge line 13 downstream of the inlet-side bypass line 48a. The temperature control valve 52 is connected to the LNG line 51.
[0031]
A component analyzer 53 for periodically analyzing a vaporized gas is connected to the discharge line 13 on the outlet side of the vaporizer 17, and the analysis value is input to a controller 54. A temperature controller 55 is provided at the top of the gas-liquid separator 14, and the detected value is input to the controller 54.
[0032]
Further, a pressure regulator 56 is connected to the gas line 19 on the outlet side of the gas heater 22, and the first pressure regulating valve 15 of the discharge line 13 is controlled so that the detected value of the pressure regulator 56 becomes a set pressure. It is supposed to be.
[0033]
Further, a calorific value analyzer 57 is connected to the gas line 19, and the calorific value analyzed by the calorific value analyzer 57 is input to the controller 54 via the temperature controller 55 and analyzed by the calorific value analyzer 57. The controller 54 sets the set temperature of the temperature controller 55 so that the generated heat value becomes the regulation value (13A).
[0034]
The gas-liquid separator 14 is provided with a liquid level gauge 58 for detecting the liquid level of the separated liquid separated, and the detected value of the liquid level gauge 58 is input to the controller 59. The flow value of the flow meter 23 connected to the gas line 19 and the flow value of the flow meter 34 connected to the liquid line 32 are input to the controller 59. The controller 59 controls the liquid level adjusting valve 33 according to the flow rate value and the detection value of the liquid level gauge 58.
[0035]
A flow control valve 60 is connected to the heating medium supply line 37 a of the bottom heater 37. A temperature controller 61 is provided below the distillation column 31, and the detected value is input to the controller 62. The controller 62 controls the flow control valve 60 according to the detected value from the temperature controller 61 and the flow value input from the flow meter 34.
[0036]
Next, the method for reducing the calorie of the high calorific value LNG of the present invention will be described.
[0037]
The LNG concentrated in the low-temperature storage tank 11 is pressurized by the discharge pump 12 and controlled by the first pressure control valve 15 so that the pressure of the pressure regulator 56 of the gas line 19 becomes a predetermined pressure, and the first vaporization is performed. The vessel 17 is entered.
[0038]
In the vaporizer 17, the LNG is heated by seawater, air, or another heating medium to become a vaporized gas of about 0 ° C. or higher.
[0039]
The vaporized gas is periodically analyzed by the component analyzer 53 to determine the composition. After that, it enters the first line mixer 18.
[0040]
The LNG whose flow rate is adjusted by the temperature adjustment valve 52 flows into the first line mixer 18 through an LNG line 51 branched from the upstream of the first pressure adjustment valve 15. The vaporized gas and LNG that have entered the first line mixer 18 are sufficiently mixed so that the two fluids are uniform.
[0041]
The temperature control valve 52 of the LNG line 51 is controlled by a controller 54 so that the temperature becomes a predetermined temperature by a temperature controller 55 installed in the gas-liquid separator 14 on the downstream side. The mixture amount of the vaporized gas and LNG is controlled, and LNG flows in.
[0042]
The set temperature of the temperature controller 55 is periodically determined from the analysis result of the component analyzer 53. The set temperature of the temperature controller 55 is, for example, about −60 ° C. (determined from gas-liquid equilibrium calculation) when the pressure is 0.6 MPa.
[0043]
The vaporized gas and LNG that have entered the first line mixer 18 are sufficiently mixed in the first line mixer 18 so that both fluids are uniform.
[0044]
The mixed fluid enters the gas-liquid separator 14 and is separated into gas and liquid by a specific gravity difference. The pressure in the gas-liquid separator 14 is adjusted to a required pressure calculated from the gas-liquid equilibrium state by a second pressure regulating valve 20 installed in the gas line 19. The separated gas is a light component having a low calorific value, and the separated liquid is a heavy component having a high calorific value.
[0045]
Since the gas flowing out of the second pressure regulating valve 20 has a low temperature, it enters the gas heater 22 and is heated to 0 ° C. or higher by seawater, air, or another heating medium.
[0046]
The outflow gas from the gas heater 22 is adjusted by the first pressure regulating valve 15 so that the pressure of the pressure regulator 56 becomes a predetermined pressure, the flow rate is measured by the flow meter 23, and the gas is stored in the buffer tank 30. Is supplied to the consuming system via the third pressure regulating valve 26.
[0047]
The buffer tank 30 is provided to moderate the pressure fluctuation of the system when the gas supply to the outside of the base fluctuates greatly. The third pressure regulating valve 26 is provided to maintain the downstream pressure at a required pressure.
[0048]
An equilibrium liquid (separated liquid) with the gas separated by the gas-liquid separator 14 is stored at the bottom of the gas-liquid separator 14, and excess liquid is sent from the bottom to the distillation column 31 via the liquid line 32.
[0049]
The surplus separated liquid sent from the gas-liquid separator 14 to the distillation column 31 is controlled by the liquid level gauge 58 and the liquid level adjusting valve 33, and at the same time, the flow rate to the distillation column 31 is controlled by the flow meter 34 for a certain time (θ). Is controlled so as to flow at a constant flow rate. This is because if the flow rate fluctuates greatly in a short time, the properties of the products at the top and bottom are not stable, and thus such control is performed. For this purpose, the separated liquid storage volume at the bottom of the gas-liquid separator 14 is stored for several hours or more of the separated amount.
[0050]
The controller 59 periodically calculates an appropriate processing amount in the distillation column 31 from the flow meter 23 and the second liquid level controller 47, transmits the calculated value to the flow meter 34, and controls the liquid level adjusting valve 33 to adjust the flow rate. By controlling, an appropriate processing amount is sent to the distillation column 31.
[0051]
The separated liquid sent to the distillation column 31 is separated into LPG and light-boiling components not less than ethane. The light-boiling components are separated as gas from the top of the column, and the LPG is separated as liquid from the bottom of the column.
[0052]
The top gas is mixed with the separated gas from the gas-liquid separator 14 through the distillation gas line 41 to be a raw material of the city gas. However, since the temperature is low, the gas at the inlet of the gas heater 22 is mixed with the separated gas of the gas-liquid separator 14. Join.
[0053]
The separated liquid from the gas-liquid separator 14 introduced into the distillation column 31 is heated and evaporated by the bottom heater 37 installed at the bottom of the column, and the LNG from the bypass line 48 is removed by the condenser 40 at the top of the column. It is cooled as a cooling medium.
[0054]
The key component for separation of the distillation column 31 is a propane component at the top and an ethane component at the bottom.
[0055]
The temperature at the top and the bottom of the column was calculated from the component analyzer 53 which regularly checks the composition of the raw material LNG, and the allowable contents of the key components at the top and the bottom were calculated and corresponded to the pressure of the distillation column 31. The flow rate of the heating medium or the cooling medium is controlled so as to reach a temperature.
[0056]
The heating fluid is controlled by the temperature controller 61 and the temperature control valve 60 so that the bottom heater 37 at the bottom of the tower has a temperature determined by the temperature controller 49 and the component analyzer 53. At the same time, the flow rate of the heat medium is controlled by the flow control valve 60 so as to secure the required heating amount at the bottom of the distillation column 31 based on the data of the flow meter 34 measuring the inflow amount of the separated liquid into the gas-liquid separator 14. Control.
[0057]
The LNG amount is controlled by the temperature controller 49 and the temperature control valve 50 so that the tower top temperature becomes a predetermined temperature.
[0058]
Since the cooling temperature of the overhead condenser 40 is normally low, the sensible heat of LNG is used as the cooling medium. Therefore, LNG is led to the condenser 40 from the upstream side of the first pressure control valve 15 and returned to the downstream side to be vaporized by the vaporizer 17 and used for gas production.
[0059]
The top gas is discharged from the inside of the tower by a tower pressure controller 42 and a pressure control valve 43 so as to maintain a predetermined pressure, and is supplied downstream of the pressure control valve 20 and upstream of the inlet of the gas heater 22. It is mixed with the separation gas of the liquid separator 14.
[0060]
When the LPG at the bottom of the tower becomes higher than the set liquid level, it is discharged out of the tower through the liquid level controller 47 and the liquid level control valve 45. The LPG is cooled to a normal temperature by a cooler 46, sent to an LPG tank, stored, and supplied to a thermally controlled raw material or other uses.
[0061]
Next, more specific examples will be described.
[0062]
(1) As an example of the composition of LNG having a calorific value of 46.05 MJ / Nm 3 (11000 kcal / Nm 3 ) or more, the following example is described as an example.
[0063]
Figure 2004099718
Although the content of C2 (ethane), C3 (propane), C4 (butane), and C5 (pentane) in the above LNG composition is small, the calorific value is about 2-3 times or more as compared with methane, which is This is a factor that makes the calorific value of city gas 46.05 MJ / Nm 3 (11000 kcal / Nm 3 ) or more.
[0064]
(2) The composition of gas and liquid is obtained from the gas-liquid equilibrium relationship of the gas in the gas-liquid separator 14 of (1). The approximate separation amount and heat value of each are as follows.
[0065]
Figure 2004099718
(3) In order to create thermal conditions in the gas-liquid separator 14, the amount of vaporized gas and the amount of cooled LNG in the vaporizer 17 are obtained by the line mixer 18.
[0066]
Figure 2004099718
(4) An example of a material balance in the case where city gas (13A) is actually manufactured based on the above-described equilibrium calculation will be described.
[0067]
Figure 2004099718
As described above, the present invention controls the respective flow rates shown in (5) under the pressure and temperature conditions set for each unit to produce a gas having a predetermined calorific value.
[0068]
The separation by the gas-liquid separator 14 when the composition of LNG does not fluctuate can theoretically obtain a gas (13A) having a predetermined calorific value if the pressure and temperature are accurately controlled. Since the gas consumption constantly fluctuates, it is actually difficult to accurately control the temperature (detection delay or the like) and the flow rate corresponding thereto.
[0069]
For this reason, in the present invention, the control value of the temperature with respect to the set pressure is set so that the calorific value of the separation gas in the gas-liquid separator 14 is lower than the specified value (13A). Fine adjustment for setting the separation gas of the gas-liquid separator 14 to a specified value (13 A) is performed by a permanent heat control equipment installed downstream. In this case, the LPG from the LPG discharge line 44 separated and recovered in the distillation column 31 is mixed with the separation gas to perform heat control.
[0070]
【The invention's effect】
In short, according to the present invention, heavy LNG is separated into gas and liquid by a gas-liquid separator, and the separated gas-liquid separated liquid is distilled in a distillation column to remove heavy components such as propane, and light components are removed. Is mixed with the gas separated by the gas-liquid separator and supplied to the consumption system, whereby the calorific value can be easily and inexpensively adjusted without deteriorating the fuel characteristics.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of the present invention.
[Explanation of symbols]
11 Low-temperature storage tank 13 Discharge line 14 Gas-liquid separator 19 Gas line 31 Distillation tower

Claims (4)

低温貯蔵タンク内で濃縮されて重質化したＬＮＧを所定の発熱量のガスに調整して消費系に供給するに際し、低温貯蔵タンクから払い出されるＬＮＧを加熱して気化し、その気化ガスと低温貯蔵タンクから払い出されるＬＮＧとを混合してその温度を調整し、気液を平衡させた後、これを気液分離器に導入して一定圧力下で気液分離し、その気液分離された重質の分離液を蒸留塔に導入して分離液から重質成分を分離すると共に軽質成分をガス化させ、そのガス化した軽質成分のガスを気液分離器で分離されたガスに混入して消費系に供給することを特徴とする高発熱量ＬＮＧの低カロリー化方法。When the LNG concentrated and heavy in the low-temperature storage tank is adjusted to a gas having a predetermined calorific value and supplied to the consumption system, the LNG discharged from the low-temperature storage tank is heated and vaporized. After mixing with LNG discharged from the storage tank to adjust the temperature and equilibrate the gas and liquid, the mixture was introduced into a gas-liquid separator and separated into gas and liquid under a constant pressure. The heavy separated liquid is introduced into the distillation column to separate heavy components from the separated liquid and gasify the light components, and the gasified light component gas is mixed with the gas separated by the gas-liquid separator. A method for reducing the calorific value of the high calorific value LNG, wherein the calorific value is supplied to a consumption system. 気液分離器で分離されたガスの温度を検出し、その温度が設定温度となるよう、上記気化ガスとＬＮＧの混合量を制御する請求項１記載の高発熱量ＬＮＧの低カロリー化方法。2. The method according to claim 1, wherein a temperature of the gas separated by the gas-liquid separator is detected, and a mixing amount of the vaporized gas and LNG is controlled so that the temperature becomes a set temperature. 蒸留塔に導入した分離液を加熱してメタン、エタンからなる軽質成分とプロパン、ブタンからなる重質成分とに分離し、その軽質成分のガスを、気液分離器で分離されたガスに混入する請求項１又は２記載の高発熱量ＬＮＧの低カロリー化方法。The separated liquid introduced into the distillation column is heated and separated into light components consisting of methane and ethane and heavy components consisting of propane and butane, and the gas of the light components is mixed with the gas separated by the gas-liquid separator. The method for reducing calories of a high calorific value LNG according to claim 1 or 2. 低温貯蔵タンク内で濃縮されて重質化したＬＮＧを所定の発熱量のガスに調整して消費系に供給するための高発熱量ＬＮＧの低カロリー化装置において、低温貯蔵タンク内の重質化したＬＮＧを払い出す払出ラインと、その払出ラインに接続された気化器と、気化器をバイパスするＬＮＧラインと、払出ラインに接続され、気化器で気化された気化ガスとＬＮＧラインからのＬＮＧを混合する第１ラインミキサーと、払出ラインに接続され、ラインミキサーで混合されたＬＮＧを導入し、これを気液分離する気液分離器と、気液分離器の頂部に接続され、分離された軽質成分のガスを消費系に供給するためのガスラインと、気液分離器で、分離された分離液を導入してこれを蒸留分離する蒸留塔と、蒸留塔で蒸留分離された軽質成分を上記ガスラインのガスに混入する蒸留ガスライとを備えたことを特徴とする高発熱量ＬＮＧの低カロリー化装置。In a high calorific value LNG calorie reducing apparatus for adjusting LNG concentrated and heavy in a low temperature storage tank to a gas having a predetermined calorific value and supplying the gas to a consumption system, the heavy material in the low temperature storage tank And a vaporizer connected to the discharge line, an LNG line bypassing the vaporizer, and a vaporized gas connected to the discharge line and vaporized by the vaporizer and LNG from the LNG line. The first line mixer to be mixed, the LNG connected to the dispensing line, and the LNG mixed by the line mixer are introduced, and the gas-liquid separator for separating the LNG is connected to the top of the gas-liquid separator. A gas line for supplying light component gas to the consuming system, a gas-liquid separator for introducing the separated liquid separated and distilling and separating the separated liquid, and a light component distilled and separated in the distillation tower. Above High heating value of LNG low calorie apparatus being characterized in that a distillation Gasurai mixed in line gas.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008157457A (en) * 2006-12-22 2008-07-10 Man Diesel Se Gas supply device for driving machine
JP2008528882A (en) * 2005-01-21 2008-07-31 クライオスター・ソシエテ・パール・アクシオンス・サンプリフィエ Natural gas supply method and apparatus
JP2012141128A (en) * 2005-07-12 2012-07-26 Conocophillips Co Lng facility with integrated ngl for enhanced liquid recovery and product flexibility
WO2014010033A1 (en) * 2012-07-11 2014-01-16 中国電力株式会社 Lng terminal, and gas and/or lng supply method for lng terminal
WO2014167219A1 (en) * 2013-04-11 2014-10-16 Gaztransport Et Technigaz Method and system for treating and feeding natural gas to an apparatus for generating power in order to propel a ship
JP2014224204A (en) * 2013-05-17 2014-12-04 大阪瓦斯株式会社 Gas production method and gas production facility
CN107560321A (en) * 2017-09-15 2018-01-09 长江大学 BOG is reclaimed and nitrogen gas liquefaction system and process
JP2018508706A (en) * 2015-02-03 2018-03-29 サムスン ヘビー インダストリーズ カンパニー リミテッド Ship fuel gas supply system
WO2019238359A1 (en) * 2018-06-15 2019-12-19 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Natural gas production apparatus and natural gas production method
CN113357531A (en) * 2021-05-21 2021-09-07 厚普清洁能源股份有限公司 System and method capable of simultaneously filling LNG cold liquid and hot liquid

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5390302A (en) * 1977-01-21 1978-08-09 Osaka Gas Co Ltd Vaporizer of liquefied natural gas
JPS53118276A (en) * 1977-03-25 1978-10-16 Mitsui Eng & Shipbuild Co Ltd Evaporation of liquefied natural gas
JPS59100195A (en) * 1982-11-30 1984-06-09 Osaka Gas Co Ltd Preparation of fuel gas with consistent calorific value from multi-component liquefied natural gas
JPS60262890A (en) * 1984-06-08 1985-12-26 Osaka Gas Co Ltd Adjustment of composition of liquefied natural gas
JPH09157668A (en) * 1995-12-06 1997-06-17 Kobe Steel Ltd Method fo controlling calorific value of natural gas and apparatus therefor
JPH10195464A (en) * 1997-01-08 1998-07-28 Osaka Gas Co Ltd Production of town gas and apparatus therefor
JP2001056096A (en) * 1999-08-12 2001-02-27 Ishikawajima Harima Heavy Ind Co Ltd Prevention method and device against forming liquid in lng tank into heavy gravity
JP2002038170A (en) * 2000-07-28 2002-02-06 Osaka Gas Co Ltd Method for producing town gas

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5390302A (en) * 1977-01-21 1978-08-09 Osaka Gas Co Ltd Vaporizer of liquefied natural gas
JPS53118276A (en) * 1977-03-25 1978-10-16 Mitsui Eng & Shipbuild Co Ltd Evaporation of liquefied natural gas
JPS59100195A (en) * 1982-11-30 1984-06-09 Osaka Gas Co Ltd Preparation of fuel gas with consistent calorific value from multi-component liquefied natural gas
JPS60262890A (en) * 1984-06-08 1985-12-26 Osaka Gas Co Ltd Adjustment of composition of liquefied natural gas
JPH09157668A (en) * 1995-12-06 1997-06-17 Kobe Steel Ltd Method fo controlling calorific value of natural gas and apparatus therefor
JPH10195464A (en) * 1997-01-08 1998-07-28 Osaka Gas Co Ltd Production of town gas and apparatus therefor
JP2001056096A (en) * 1999-08-12 2001-02-27 Ishikawajima Harima Heavy Ind Co Ltd Prevention method and device against forming liquid in lng tank into heavy gravity
JP2002038170A (en) * 2000-07-28 2002-02-06 Osaka Gas Co Ltd Method for producing town gas

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008528882A (en) * 2005-01-21 2008-07-31 クライオスター・ソシエテ・パール・アクシオンス・サンプリフィエ Natural gas supply method and apparatus
JP2012141128A (en) * 2005-07-12 2012-07-26 Conocophillips Co Lng facility with integrated ngl for enhanced liquid recovery and product flexibility
JP2008157457A (en) * 2006-12-22 2008-07-10 Man Diesel Se Gas supply device for driving machine
JP5653563B2 (en) * 2012-07-11 2015-01-14 中国電力株式会社 LNG base
WO2014010033A1 (en) * 2012-07-11 2014-01-16 中国電力株式会社 Lng terminal, and gas and/or lng supply method for lng terminal
JPWO2014010033A1 (en) * 2012-07-11 2016-06-20 中国電力株式会社 LNG base
WO2014167219A1 (en) * 2013-04-11 2014-10-16 Gaztransport Et Technigaz Method and system for treating and feeding natural gas to an apparatus for generating power in order to propel a ship
FR3004513A1 (en) * 2013-04-11 2014-10-17 Gaztransp Et Technigaz METHOD AND SYSTEM FOR PROCESSING AND DELIVERING NATURAL GAS TO ENERGY PRODUCTION EQUIPMENT FOR VESSEL PROPULSION
US10012350B2 (en) 2013-04-11 2018-07-03 Gaztransport Et Technigaz Method and system for treating and feeding natural gas to an apparatus for generating power in order to propel a ship
JP2014224204A (en) * 2013-05-17 2014-12-04 大阪瓦斯株式会社 Gas production method and gas production facility
JP2018508706A (en) * 2015-02-03 2018-03-29 サムスン ヘビー インダストリーズ カンパニー リミテッド Ship fuel gas supply system
CN107560321A (en) * 2017-09-15 2018-01-09 长江大学 BOG is reclaimed and nitrogen gas liquefaction system and process
WO2019238359A1 (en) * 2018-06-15 2019-12-19 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Natural gas production apparatus and natural gas production method
JP2019219062A (en) * 2018-06-15 2019-12-26 レール・リキード−ソシエテ・アノニム・プール・レテュード・エ・レクスプロワタシオン・デ・プロセデ・ジョルジュ・クロード Natural gas production apparatus and natural gas production method
CN112119275A (en) * 2018-06-15 2020-12-22 乔治洛德方法研究和开发液化空气有限公司 Natural gas production plant and natural gas production method
JP7084219B2 (en) 2018-06-15 2022-06-14 レール・リキード－ソシエテ・アノニム・プール・レテュード・エ・レクスプロワタシオン・デ・プロセデ・ジョルジュ・クロード Natural gas production equipment and natural gas production method
CN113357531A (en) * 2021-05-21 2021-09-07 厚普清洁能源股份有限公司 System and method capable of simultaneously filling LNG cold liquid and hot liquid

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