CN1121173A - 空气分离 - Google Patents
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Abstract
空气在压缩机2中压缩、在纯化单元4中纯化、流过主热交换器6而冷却并在包括高压精馏塔14和低压精馏塔18的双精馏塔12中分离。氩增浓的氧蒸汽物流通过出口39从低压精馏塔18采出,而氩产物在配备氩冷凝器48的氩精馏塔40中分离。氩在冷凝器48中在塔14和18操作压力之间的压力下与第二部分空气物流间接换热而冷凝。第二部分空气物流部分冷凝并送入相分离器60。从相分离器60采出液相物流,使它依次流过节流阀62和冷凝器48。因而为冷凝器48提供进一步的冷却作用。
Description
本发明关于分离空气的方法和装置。
工业上分离空气最重要的方法是采用精馏。在典型的空气精馏过程中采用的步骤有:压缩空气物流、除去得到的压缩空气中的水蒸汽和二氧化碳使它纯化和通过与返回的产物物流热交换预冷却压缩空气物流至适于精馏的温度。精馏在所谓“双精馏塔”中进行,该双精馏塔包括一个高压塔和一个低压塔,即其中一个塔在较另一个塔高的压力下运行。大部分进入空气被送入高压塔且被分离成氧增浓(oxygen-enriched)液体空气和氮蒸汽。将氮蒸汽冷凝。部分冷凝液用作高压塔的液体回流液。氧增浓液体从高压塔的底部采用,并用于形成低压塔的进料物流。氧增浓液体物流一般被过冷却并通过节流阀或减压阀送入低压塔的中部。氧增浓液体空气在低压塔内分离成基本上纯的氧和氮。气态氧和氮产物从低压塔引出并且通常形成与进入空气进行热交换的返回物流。以来自高压塔的冷凝液中的剩余部分作为低压塔的液体回流物,过冷却之并通过节流阀将它送入低压塔的顶部。通过使液体氧再沸腾,在低压塔内形成从底部上升的蒸汽流。再沸腾通过使低压塔底部的液体氧与来自高压塔的氮热交换实现。结果形成冷凝的氮蒸汽。
局部浓度最高的氩形成于低压塔的中部位置,氧增浓液体空气从该位置之下送入。如果希望得到氩产物,则氩增浓氧蒸汽物流从低压塔中氩体积浓度一般在5%至15%范围的位置附近采出,并送入一个侧塔(side column)的底部,氩产物在该侧塔中分离出来。氩塔的回流物由此塔塔顶冷凝器提供。冷凝器由至少一部分氧增浓液体空气冷却,这部分氧增浓液体空气然后送入低压塔。
EP-B-0377117说明了上述方法的一个实例。在趋于降低低压精馏塔中液/气比例的某些条件下实施此方法出现的问题是氩的产率往往低于不降低液/气比例的情况。造成此现象发生的条件的实例有将比例相当大的原料空气直接送入低压精馏塔、直接从高压塔中采出氮产物和向双精馏塔中送入比例相当大的液态原料空气。造成不希望的氩低产率的另一原因是低压精馏塔的塔板数不足或填料高度不够。本发明的一个目的是提供这样一种方法和装置,使得在这些情况下或至少在其中一些情况下,比EP-B-0377117所述方法更能保持氩的产率。
按照本发明提供的分离空气方法包括:压缩和纯化空气;在包括一个高压塔和一个低压塔的双精馏塔中精制第一部分压缩纯化的空气物流;从双精馏塔中采出富氧产物和富氮产物物流;在氩精馏塔中精制采自低压塔的氩增浓流体,从而在氩精馏塔塔顶获得富氩蒸汽;至少冷凝一部分所述富氩蒸汽且在氩精馏塔中至少采用一部分形成的冷凝液作为回流液;和从氩精馏塔中采出富氩产物物流,本方法的特征在于使第二部分液态压缩纯化的空气物流在高于低压塔塔顶压力但低于高压塔塔顶压力的压力下部分再沸腾,从而形成氧增浓液体和贫氧蒸汽;使氧增浓液体与贫氧蒸汽分离;冷凝贫氧蒸汽物流和将冷凝的贫氧蒸气物流送入低压精馏塔,其中通过使第二部分空气物流与所述冷凝富氩蒸汽过程间接换热进行第二部分空气物流的部分再沸腾。
本发明还提供了这样一种空气分离装置,它包括:包括一个高压塔和一个低压塔、用于精制第一部分压缩纯化的空气物流的双精馏塔,所述双精馏塔有一个富氧产物物流出口和一个富氮产物物流出口;氩精馏塔,它有一个与低压塔中所述氩增浓流体物流的出口相连通的氩增浓流体物流入口、一个氩精馏塔中富氩产物的出口;和第一冷凝器,用于冷凝在氩精馏塔中分离出的富氩蒸汽并将至少一部分冷凝液送到氩精馏塔作为回流液,其特征在于第一冷凝器包括一套热交换管,用于在比低压塔塔顶压力高但比高压塔塔顶压力低的压力下使第二部分液态压缩纯化的空气物流部分再沸腾,从而形成所用的氧增浓液体和贫氧蒸汽;此装置还包括一个相分离器,用于分离氧增浓液体和贫氧蒸汽,和一个第二冷凝器,它具有用于冷凝贫氧蒸汽物流的热交换管,所述第一冷凝器的再沸腾管与低压塔相连通。
所述分离的氧增浓液体优选用于冷凝作用。在本发明方法的一个优选实施方案中,分离的氧增浓液体物流过适宜设备如节流阀而压力降低,所形成压力降低的氧增浓液体物流在冷凝所述富氩蒸汽过程中补充第二部分空气物流。因此,此例中的第一冷凝器还有另一套供压力降低的氧增浓液体物流用的再沸腾管。压力降低的氧增浓液体物流本身与冷凝富氩蒸汽过程间接换热而再沸腾,所形成的再沸腾物流优选送入低压精馏塔。分离出的氧增浓液体也可用来起不同的冷凝作用,例如在位于氩塔中两个中间质量交换面(intermediate mass exchange levels)之间的冷凝器中起冷凝作用。在本发明方法的这样一个实例中,分离出的氧增浓液体物流可在与所述分离进行过程基本相同的压力下进入所述中间冷凝器,并且所得的再沸腾氧增浓液体优选返回低压精馏塔。如果能够获得特别高的液体空气生成率,则有时也可能采用另一种方案,即使用分离出的氧增浓液体第二部分物流冷凝贫氧蒸汽,而第二部分物流本身再沸腾,并优选送入低压精馏塔。
贫氧蒸汽物流优选通过与来自高压塔的氧增浓液体物流间接换热而被冷凝。这种热交换之后,所得再沸腾的氧增浓液体优选送入低压精馏塔。
例如通过使压缩、纯化的空气物流与液态富氧产物物流换热并使已换热的压缩纯化的空气物流通过节流阀可形成第二部分液态压缩纯化的空气物流。
如果需要,第二部分压缩纯化的空气物流也可以液态从高压塔的中间质量交换面采出,该面几乎与前体压缩纯化的空气物流以液态送入的中间质量交换面相同。此方案是使第二部分压缩纯化的空气物流生成速率不同于例如通过与液体氧气产物换热而使空气液化的速度的一个实例。如果第二部分空气物流的来源是高压塔的所述中间面,则第二部分空气物流的组成近似于前体空气物流的组成,但可以含有例如22%或23%(体积)的氧。
现在参照附图,以实施例说明本发明的方法和装置,其中:
图1为本发明的第一种空气分离装置的示意流程图;和
图2为本发明的第二种空气分离装置的示意流程图。
示意图不是按比例的。
参照附图1,原料空气物流于压缩机2中压缩,得到的压缩原料空气物流通过纯化单元4,有效地除去其中的水蒸汽和二氧化碳。单元4采用吸附剂床(未示出)除去水蒸汽和二氧化碳。各床层的运行并不同步,这样,当一个或多个床纯化原料空气物流时,则其余的床例如用热氮气物流再生。这种纯化单元和它们的操作是本领域公知的,无需进一步说明。
从纯化空气中取出第一部分空气物流并从主换热器6的暖端8流入此主热交换器到达它的冷端10。这样第一部分空气物流的温度从大约室温降至适于精馏分离的温度(例如它的露点)。冷却的第一部分空气物流经位于高压塔14上的比所有液-气质量交换设备(未示出)位置都低的入口16送入高压塔14。高压塔14构成还包括低压精馏塔18的双精馏塔12的一个部分。在高压精馏塔14中,上升蒸汽与下降液体密切接触,并可能在填料或塔板形式的液-气质量交换设备上发生质量交换。从高压精馏塔14顶部采出氮蒸汽,在冷凝器一再沸腾20的冷凝管中冷凝蒸汽并将所得冷凝液的一部分送回塔14顶部,这样就产生了下降液体,并作为回流液而向下流经高压塔。随着蒸汽沿高压塔14上升,它逐渐被氮增浓。
与经入口16进入高压塔14的空气接近于平衡,并因此而多少被氧增浓的液体在高压精馏塔14的底部聚集。这种氧增浓的液体空气物流通过出口22从高压精馏塔14采出并流经热交换器24被过冷却。过冷却的氧增浓液体空气物流分成两股支物流。一股支物流经节流阀26并通过入口28进入低压精馏塔18。第二股过冷却的氧增浓液体空气的支物流的流程将在下面叙述。
通过入口28进入低压精馏塔18的氧增浓液体空气在其中分为氧和氮。在低压精馏塔18中采用液-气接触设备(未示出)使下降液体和上升蒸汽进行质量交换。由于这种质量交换,上升蒸汽逐渐变得更加富氮,而下降液体逐渐变得更加富氧。液-气接触设备(未示出)可以是蒸馏塔板或填料的形式。为了给低压精馏塔18提供液体氮回流液,从冷凝器-再沸器20采出一股液体氮冷凝液物流,并且不是和其余的冷凝液一起送回高压塔,而是流经换热器24被过冷却。过冷却的液体氮物流分成两股支物流。其中一股支物流流经节流阀30并通过入口32送入低压精馏塔18塔顶。液体氮的另一股支物流流经节流阀34,作为产物收集于绝热贮罐(未示出)中。
冷凝器-再沸器20在低压精馏塔18底部使液体氧再沸腾,并以此提供塔18内的上升蒸汽流。通过泵36的运转使液体氧的压力升至选定的、一般高于高压精馏塔14塔顶压力的高压,从而经出口34从低压精馏塔18的底部采出液体氧物流。如果需要,泵36可将氧升压至超临界压力。获得的加压氧物流从热交换器6的冷端10到暖端8流过交换器6,因此被暖热至大约室温。若需要,也可采出液体氧产物的第二部分物流,并作为液体产物收集。
通过出口38从低压精馏塔18的塔顶采出气态氮产物,并在热交换器24内通过与正被过冷却的物流逆流换热被升温,并且从主热交换器6的冷端10到暖端8流过主热交换器6而被进一步升温至大约室温。如果此氮产物没有用处,则可排入大气。
为了生产氩产物,通过低于入口28平面并且低于塔的质量交换面的出口39从低压精馏塔18采出氩增浓的氧蒸汽物流,出口39平面处的氩浓度最大。一般含有5%至15%(体积)氩的氩增浓氧蒸汽物流通过入口42送入氩精馏塔40。液-气接触设备(未示出)位于氩精馏塔40中,并使上升蒸汽相与下降液体相之间在塔40中发生质量传递。液-气接触设备一般为低压降填料形态,如由Sulzer Brothers出售的商标为MELLAPAK的结构填料。根据塔40内的填料高度,可生产出一般含氧杂质例如最高达2%的氩产物。如果采用足够高的填料,氩中氧杂质的含量可降至少于10ppm(体积)。贫氩的氧物流从氩精馏塔40的底部采出并通过入口44返回低压精馏塔18。根据氩精馏塔40塔底高度与入口44高度的相对关系,可采用泵46将贫氩液体氧从氩精馏塔40底部传送至低压精馏塔18。
氩精馏塔40的回流液通过在第一冷凝器48的冷凝管中冷却采自塔40塔顶的富氩蒸汽而提供。所得冷凝液的一部分作为回流液返回塔40塔顶,而其余部分通过导管50作为液氩产物取出。若需要,在另一工艺中,可将一部分富氩蒸汽作为氩产物取出而来自第一冷凝器48的全部冷凝液则作为回流液返回氩塔40的塔顶。另一工艺是在氩塔塔顶以下几个理论塔板的质量交换面处取出氩产物,从而使氩产物中氮含量最低。另外,若需要,可采用单独的分馏塔来从氩中分离氮杂质。
为了向冷凝器48提供冷却作用,来自单元4的不作为第一部分空气物流的那部分纯化空气在三个串连的压缩机52、54和56中进一步被压缩。离开压缩机56的一部分压缩空气当作第二部分空气物流并使它从主热交换器的暖端8流到冷端10而在其中冷却。这样冷却的第二部分空气物流流过热交换器24而被进一步冷却。第二部分空气物流从热交换器24出来流过节流阀58,使它降压至大约2.3巴。如果第二部分空气物流在节流阀58的入口处不是液态(因为它处于超临界压力),那么流经节流阀58将使它转变成基本上液态,尽管也可能生成一些闪蒸气体(flashgas)。第二部分液体空气物流离开节流阀58,流经第一冷凝器48,并提供一部分在冷凝器48中冷凝富氩蒸汽所需的冷却作用。通过与富氩蒸汽的冷凝过程间接换热,第二部分空气物流部分再沸腾。一般而言,第一冷凝器48的热交换管入口的第二部分空气物流中的40%至60%(体积)的液态空气在流经这些热交换管过程中汽化。因为氧比氮难挥发,故而在冷凝器48中的部分再沸腾具有使液相富氧而气相贫氧的效果。部分再沸腾的第二部分空气物流离开第一冷凝器48后液相和气相在相分离器60中彼此分离。所得氧增浓液体例如含氧约32%(体积),从相分离器60的底部采出,流经节流阀62而降压,并流经第一冷凝器48的另一套热交换管,从而提供在其中冷凝氩蒸汽所需的其余冷却作用。氧增浓液体物流在通过第一冷凝器48的过程中再沸腾,并且所得到的蒸汽通过在入口44之上,入口28之下的低压精馏塔质量交换面上的入口64,送入低压精馏塔18而在其中分离。一般而言,节流阀62使来自相分离器60的氧增浓液体的压力降至接近低压精馏塔18在入口64平面上的操作压力。
贫氧蒸汽物流例如含氧约13%(体积),从相分离器60的顶部采出并流过第二冷凝器66的冷凝热交换管而冷凝。所得到的贫氧冷凝液流过节流阀68并通过在低压精馏塔18入口32之下、入口28之上的质量交换面上的入口70送入低压精馏塔18。第二冷凝器66的冷却作用通过下述方式提供:取出由出口22从高压塔14采出的过冷却氧增浓液态空气的第二股支物流(即不是通过入口28送入低压精馏塔18的那部分过冷却氧增浓液态空气),并使它流过另一节流阀72。得到的减压氧增浓液态空气流过第二冷凝器66的再沸管并通过与贫氧蒸汽间接换热而在冷凝器66中再沸腾。来自第二冷凝器66的再沸腾物流通过通常在与入口64近似相同的质量交换面上的入口74送入低压精馏塔18。
通过入口44、64、70和74送入低压精馏塔18的各种物流在其中分离,而氧增浓液态空气物流通过入口28送入。一般在塔18中产生杂质含量基本上小于1%(体积)的氧和氮产物。
如同在本领域中众所周知的一样,图1中所示装置的制冷作用的产生速度取决于液体产物的生产速度。图1所示装置用以以高于氧气总产量15%的速度生产液体产物。因此,需要相当大的制冷量,所以采用两台膨胀涡轮机(expansion turbine)来产生必要的制冷作用。“热”涡轮机76在接近于室温温度下从压缩机56的出口取空气,使它随着对外做功膨胀至稍高于高压精馏塔14底部压力的压力。使产生的膨胀空气物流以约为160K温度离开涡轮机76,并从主热交换器6的中部送入其中。膨胀的空气物流从热交换器6的中部流至其冷端10,并在主热交换器6冷端10下游的第一部分空气物流区与第一部分空气物流混合。进一步致冷作用通过下列方式提供:从压缩机52出口取出一部分压缩空气物流,并使它从主热交换器6的暖端8到其中部流经主热交换器6,一般在约160K温度从中部采出,使它随着对外做功在第二膨胀涡轮机中膨胀。使得形成的膨胀空气在适于其精馏的温度及在接近于高压塔14底部压力的压力下离开涡轮机78。来自膨胀涡轮机78的膨胀空气在主热交换器6冷端10下游的第一部分空气物流区与第一部分空气物流混合。
现参照附图2,所示装置除一部分外其余部分与图1所示的装置相类似。因此,两图中相同的部分用同一代码表示。此外,在此仅说明图2所示装置与图1所示装置的不同部分及其操作。此不同之处涉及第二部分空气物流的形成。在图1所示装置中,第二部分空气物流取自压缩机56。在图2所示装置中,第二部分空气物流取自高压塔14中间质量交换面上的出口80。为了使得第二部分空气物流能这样以液态从高压塔14采出而不对塔的工作效率产生不利的影响,将前体物流经在与出口80相同的质量交换面上的入口82引入到高压精馏塔14中。前体物流由一部分离开压缩机56出口的空气构成。前体物流通过从主热交换器6的暖端8到冷端10流经该主热交换器冷却至适于其精馏的温度。这样冷却的前体物流流经节流阀84到达入口82。
在图1和2所示装置中,存在许多易于降低低压精馏塔18上部液/气(L/V)比的因素。这些因素包括:将液态空气引入低压精馏塔18(由于要使加压液态氧汽化形成气态氧产物故而形成液态空气)和用一部分在高压塔14分离出的氮气形成氮气产物而非双精馏塔12的液体氮回流物。这种降低的L/V比率的效应将.降低氩产物的产率。与氩塔冷凝器仅以采自高压精馏塔底部的一部分氧增浓液体冷却的常规方法相比,本发明方法能够提供更高的L/V比率,使得能在常规产物不能获得此结果时保持氩的高产率,因此比较而言,本发明的方法对于给定的能源消耗能够得到更高的氩产率。与此相类似,在本发明方法的另一实例中(未在附图示出),通过采用利用出口直接与低压精馏塔中间质量交换区相连通的膨胀涡轮机的制冷***,可使得更大比例的总原料空气流过涡轮机,从而在可不降低氩产率的情况下,降低总能耗(与常规工艺相比),或者说例如能以更高的速度从高压精馏塔分离的氮中采出氮产物。
从本发明获取确实的经济利益的另一方法是利用“理论塔板”数比常规方法少而不降低氩产率的低压精馏塔。因此可降低低压精馏塔的投资费。
上述优点因氩塔顶部冷凝器内的汽化流体与冷凝流体之间较高的温度差而获得,此温度差由选择向氩冷凝器提供冷凝作用的流体而产生。
在附图2所示装置的典型操作实例中,压缩机2出口压力约6巴,压缩机52出口压力约23巴,压缩机56出口压力约65巴,膨胀涡轮机76出口压力约6巴,膨胀涡轮机78出口压力约6巴,液态氧泵36出口压力为30巴。此外,虽然在图2未示出,压力约为5.6巴的中压气态氮产物直接从高压精馏塔14的顶部采出。低压精馏塔18在其塔顶压力约为1.4巴条件下操作,氩精馏塔40在其塔顶压力约为1.3巴条件下操作。在此实例中,液态氮产物约以氧生成(既包括气态也包括液态)速率的17.5%的速率产出。液态氧产物以与液态氮产物相同的速率产出。此外,中压气态氮产物以与液体氮产物大约相同的速率直接从高压塔14采出。氩产率或回收率为90%(基于原料空气中氩含量)。
Claims (12)
1.分离空气的方法,包括:压缩和纯化空气;在包括一个高压塔和一个低压塔的双精馏塔中精制第一部分压缩纯化的空气物流;从双精馏塔中采出富氧产物和富氮产物物流;在氩精馏塔中精制采自低压塔的氩增浓流体,从而在氩精馏塔塔顶获得富氩蒸汽;至少冷凝一部分所述富氩蒸汽且在氩精馏塔中至少采用一部分形成的冷凝液作为回流液;和从氩精馏塔中采出富氩产物物流,本方法的特征在于使第二部分液态压缩纯化的空气物流在高于低压塔塔顶压力但低于高压塔塔顶压力的压力下部分再沸腾,从而形成氧增浓液体和贫氧蒸汽;使氧增浓液体与贫氧蒸汽分离;冷凝贫氧蒸汽物流和将冷凝的贫氧蒸气物流送入低压精馏塔,其中通过使第二部分空气物流与所述冷凝富氩蒸汽过程间接换热进行第二部分空气物流的部分再沸腾。
2.根据权利要求1的方法,其中所述分离的氧增浓液体用于起冷凝作用。
3.根据权利要求2的方法,其中分离的氧增浓液体的一股物流降压,并且形成的降压的氧增浓液体物流在冷凝所述富氩蒸汽过程中补充第二部分空气物流。
4.根据权利要求3的方法,其中降压的氧增浓液体物流本身通过与冷凝富氩蒸汽过程间接换热而再沸腾,且形成的再沸腾物流送入低压精馏塔。
5.根据前述权利要求中任一项的方法,其中贫氧蒸汽物流通过与采自高压塔的氧增浓液体物流间接换热而冷凝。
6.根据权利要求5的方法,其中采自高压塔的所述氧增浓液体物流通过与贫氧蒸汽换热而再沸腾,并且形成的再沸腾氧增浓液体物流送入低压精馏塔。
7.根据前述权利要求中任一项的方法,其中第二部分压缩纯化的空气物流通过使压缩纯化的气态空气物流与液态富氧产物物流换热而以液态形成并且使热交换过的压缩纯化空气物流流过节流阀。
8.根据权利要求1至6中任一项的方法,其中第二部分压缩纯化的空气物流以液态从高压塔中的与前体压缩纯化的空气物流以液态送入的中间质量交换面相同的中间质量交换面采出。
9.根据前述权利要求中任一项的方法,其中第二部分压缩纯化的空气物流中40%至60%(体积)的液态空气通过与冷凝氩蒸汽过程换热而汽化。
10.空气分离装置,包括:包括一个高压塔和一个低压塔、用于精制第一部分压缩纯化的空气物流的双精馏塔,所述双精馏塔有一个富氧产物物流出口和一个富氮产物物流出口;氩精馏塔,它有一个与低压塔中所述氩增浓流体物流的出口相连通的氩增浓流体物流入口、一个氩精馏塔中富氩产物的出口;和第一冷凝器,用于冷凝在氩精馏塔中分离出的富氩蒸汽并将至少一部分冷凝液送到氩精馏塔作为回流液,其特征在于第一冷凝器包括一套热交换管,用于在比低压塔塔顶压力高但比高压塔塔顶压力低的压力下使第二部分液态压缩纯化的空气物流部分再沸腾,从而形成所用的氧增浓液体和贫氧蒸汽;此装置还包括一个相分离器,用于分离氧增浓液体和贫氧蒸汽,和一个第二冷凝器,它具有用于冷凝贫氧蒸汽物流的热交换管,所述第一冷凝器的再沸腾管与低压塔相连通。
11.根据权利要求10的空气分离装置,还包括用于降低分离出的氧增浓液体物流压力的减压设备,并且其中第一冷凝器还有另一套用于使降压的氧增浓液体物流再沸腾的热交换管,所述第一冷凝器的再沸腾管与低压塔相连通。
12.根据权利要求10或11的空气分离装置,其中第二冷凝器含有再沸腾管,再沸腾管在其入口处与高压塔的氧增浓液体出口相连通,并在其出口处与高压塔中再沸腾的氧增浓液体的入口相连通。
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9410696A GB9410696D0 (en) | 1994-05-27 | 1994-05-27 | Air separation |
GB9410696.0 | 1994-05-27 |
Publications (1)
Publication Number | Publication Date |
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CN1121173A true CN1121173A (zh) | 1996-04-24 |
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Application Number | Title | Priority Date | Filing Date |
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CN95105530A Pending CN1121173A (zh) | 1994-05-27 | 1995-05-26 | 空气分离 |
Country Status (9)
Country | Link |
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US (1) | US5546766A (zh) |
EP (1) | EP0684438B1 (zh) |
CN (1) | CN1121173A (zh) |
AU (1) | AU684920B2 (zh) |
DE (1) | DE69503095T2 (zh) |
GB (1) | GB9410696D0 (zh) |
PL (1) | PL178373B1 (zh) |
TW (1) | TW283760B (zh) |
ZA (1) | ZA954130B (zh) |
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CN102770731A (zh) * | 2008-08-21 | 2012-11-07 | 普莱克斯技术有限公司 | 用于分离空气的方法和设备 |
CN101535755B (zh) * | 2006-01-12 | 2014-05-07 | 普莱克斯技术有限公司 | 低温空气分离*** |
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DE4443190A1 (de) * | 1994-12-05 | 1996-06-13 | Linde Ag | Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft |
WO1997001068A1 (fr) * | 1995-06-20 | 1997-01-09 | Nippon Sanso Corporation | Procede et appareil de separation de l'argon |
GB9513766D0 (en) * | 1995-07-06 | 1995-09-06 | Boc Group Plc | Air separation |
US5701764A (en) * | 1996-08-06 | 1997-12-30 | Air Products And Chemicals, Inc. | Process to produce moderate purity oxygen using a double column plus an auxiliary low pressure column |
FR2774752B1 (fr) * | 1998-02-06 | 2000-06-16 | Air Liquide | Installation de distillation d'air et boite froide correspondante |
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US6116052A (en) * | 1999-04-09 | 2000-09-12 | Air Liquide Process And Construction | Cryogenic air separation process and installation |
US6196024B1 (en) | 1999-05-25 | 2001-03-06 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Cryogenic distillation system for air separation |
US6276170B1 (en) | 1999-05-25 | 2001-08-21 | Air Liquide Process And Construction | Cryogenic distillation system for air separation |
US6202441B1 (en) | 1999-05-25 | 2001-03-20 | Air Liquide Process And Construction, Inc. | Cryogenic distillation system for air separation |
US6347534B1 (en) | 1999-05-25 | 2002-02-19 | Air Liquide Process And Construction | Cryogenic distillation system for air separation |
JP3715497B2 (ja) * | 2000-02-23 | 2005-11-09 | 株式会社神戸製鋼所 | 酸素の製造方法 |
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DE102007031765A1 (de) * | 2007-07-07 | 2009-01-08 | Linde Ag | Verfahren zur Tieftemperaturzerlegung von Luft |
WO2010030441A2 (en) * | 2008-09-09 | 2010-03-18 | Conocophillips Company | System for enhanced gas turbine performance in a liquefied natural gas facility |
US8528363B2 (en) * | 2009-12-17 | 2013-09-10 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Process and apparatus for the separation of air by cryogenic distillation |
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-
1994
- 1994-05-27 GB GB9410696A patent/GB9410696D0/en active Pending
-
1995
- 1995-05-12 TW TW084104718A patent/TW283760B/zh active
- 1995-05-19 AU AU20165/95A patent/AU684920B2/en not_active Ceased
- 1995-05-19 ZA ZA954130A patent/ZA954130B/xx unknown
- 1995-05-22 US US08/446,998 patent/US5546766A/en not_active Expired - Fee Related
- 1995-05-26 DE DE69503095T patent/DE69503095T2/de not_active Expired - Fee Related
- 1995-05-26 CN CN95105530A patent/CN1121173A/zh active Pending
- 1995-05-26 PL PL95308805A patent/PL178373B1/pl unknown
- 1995-05-26 EP EP95303598A patent/EP0684438B1/en not_active Expired - Lifetime
Cited By (2)
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---|---|---|---|---|
CN101535755B (zh) * | 2006-01-12 | 2014-05-07 | 普莱克斯技术有限公司 | 低温空气分离*** |
CN102770731A (zh) * | 2008-08-21 | 2012-11-07 | 普莱克斯技术有限公司 | 用于分离空气的方法和设备 |
Also Published As
Publication number | Publication date |
---|---|
PL308805A1 (en) | 1995-12-11 |
ZA954130B (en) | 1996-01-19 |
EP0684438A1 (en) | 1995-11-29 |
PL178373B1 (pl) | 2000-04-28 |
GB9410696D0 (en) | 1994-07-13 |
DE69503095T2 (de) | 1998-11-05 |
AU2016595A (en) | 1995-12-07 |
DE69503095D1 (de) | 1998-07-30 |
US5546766A (en) | 1996-08-20 |
TW283760B (zh) | 1996-08-21 |
EP0684438B1 (en) | 1998-06-24 |
AU684920B2 (en) | 1998-01-08 |
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