CN1135351C - 生产氩的塔结构和氩的生产方法 - Google Patents

生产氩的塔结构和氩的生产方法 Download PDF

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CN1135351C
CN1135351C CNB98115980XA CN98115980A CN1135351C CN 1135351 C CN1135351 C CN 1135351C CN B98115980X A CNB98115980X A CN B98115980XA CN 98115980 A CN98115980 A CN 98115980A CN 1135351 C CN1135351 C CN 1135351C
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D·P·波纳奎斯特
M·J·罗克特
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Abstract

本文涉及一种在低温空气分离系统中为在低压塔中获得为氩塔供应含低水平氮的进料的系统，该系统利用低压塔中两个高度相等的结构性填料床，在其间对液体进行混合和再分配。该填料床位于来自氩塔顶部冷凝器的进料点和氩塔出料点之间。

Description

生产氩的塔结构和氩的生产方法
技术领域
本发明涉及氩的生产，更具体而言，涉及低温空气分离系统的低压塔的结构，该系统为氩蒸馏塔提供基本不含氮的富氩进料。
背景技术
氩气用于冶金工业，具体而言，用于钢和特殊钢的氩-氧脱气和各种金属的切割和焊接。等离子体射流炬利用加热到超过10000°K的氩气混合物用于切割操作和用于用难熔材料涂敷金属。最近氩气成为电子工业的重要成分如作载气、清洗气或作为从某些制造过程中排除空气的覆盖气，特别是在晶体生长，离子碾磨和其它蚀刻过程中。
氩的生产是工业气体生产的重要经济因素。一般说来，氩是低温空气分离的副产品。但是，为生产所需纯度的氩还需要一系列附加生产步骤。重要的纯度要求之一是所含氮的浓度。氩的多种应用要求基本上不含氮。
在低温蒸馏塔中采用结构性填料提供了一种利用填料在低压降下良好传质性能的机会(参见Meier的美国专利4,296,050)。采用结构性填料可在低温空气分离工厂的低压塔增加大量理论板，而又不受大压降的影响，从而显著改善氩生产的经济效果。
过去，高纯氩的生产包括一系列生产粗氩物流的生产步骤，然后粗氩物流在精制装置提高品位。氩的处理从低温空气分离厂的低压塔开始。低品位氩物流从低压塔的中间点流出。然后将低品位氩物流送入氩塔，在塔中经分离为含有约97.5％氩的塔顶粗氩物流和返回低压塔的塔底物流。典型的塔顶物流含有约1.5％氧和1.0％氮。
然后将来自氩塔塔顶的粗氩物流加热到空温，这时添加氢，并将混合物加压送入催化脱氧炉以除氧。将燃烧过的氩冷却、干燥，然后继续冷至液化温度。将冷氩物流再送入精炼塔以去除过量的氢和残余的氮。正常生产得到的氩产品流含低于5ppm的氮或氧。
德国专利1048936描述了减少氩塔进料中氮含量的方法。所建议的方法增加在氩冷凝器进料和氩塔出料点之间的低压塔段所采用的板数。在低压塔采用附加板，其目的在于减少氩塔进料中的氮含量，却带来压降损失，后者增加空气压缩机出口压力，因而增加能耗。此外，提高压力水平会使塔内相对挥发度减小，从而使氩的收率降低。
在Bianchi等的美国专利5,133,790，7月28日，1992中(发明内容引于本文作为参考)建议采用结构性填料增加在氩冷凝器进料和氩塔出料点之间的低压塔的平衡塔板数。低压塔的附加精馏是由引入结构性填料而不是增加板提供的。这大大降低氮的浓度，同时将氩浓度保持在或接近最大值，可直接生产不含氮的氩。采用结构性填料，而不是增加板，可避免能量损失和氩收率减少。
Bianchi等提出的系统的全尺寸规模试验(该系统在整个低温塔中皆采用结构性填料)表明，很难降低氩塔进料中氮的水平。曾经尝试，在氩冷凝器进料和氩塔出料点之间利用单个填料床以达到低氮水平，其效果未能令人满意。
发明内容
本发明之目标在于提供一种改进的氩生产系统，该系统利用含结构性填料的低压蒸馏塔。
本发明之另一目标在于提供一种改进的氩生产系统，其中由低压塔进入氩塔的进料基本上不含氮。
为获得含氮量低(通常为10ppm)的氩产品，应使为低温空气分离系统的氩塔供料的低压塔段中的氮含量水平降低。达到此目的的方法是在低压塔中利用两个高度相等的结构性填料床，两床之间有液体的混合和再分配。填料床布置在氩塔冷凝器进料和氩塔出料点之间的塔段。
附图说明
图1为结合本发明采用的氩生产装置的流程图。
图2为本发明一种实施方案图，该图表示低压塔中部件的布置情况，该塔能保证含有很低水平氮的富氩物流进入氩塔。
图3为塔段的计算特性与本发明所采用的低压塔的较低的结构性填料床中理论塔板的百分数的关系图。
在叙述发明之前，值得定义在本说明书和权利要求中所采用的某些术语。术语“塔”表示蒸馏或精馏塔或区段，即接触塔或区段，其中液相和汽相逆流以实现混合流体的分离，例如，通过在一系列安装在塔和/或填料元件上垂直隔开的板或盘上的汽相和液相的接触。有关蒸馏塔的进一步讨论参见化学工程师手册(Chemical Engineers’Handbook)，第五版，主编R.H.Perry和C.H.Chilton，McGraw-Hill出版社，纽约，第十三章，“蒸馏”(Distillation)B.D.Smith等，13-3页，连续蒸馏过程(The Continuous Distillation Process)。术语双塔用于表示高压塔，其上端与低压塔的下端有热交换关系。有关双塔的进一步讨论可参见Rnheman“气体的分离”(The Separation of Gases)牛津大学出版社，1949，VII章，工业用空气分离(Commercial Air Separation)。
蒸汽和液体接触分离过程取决于蒸汽压力差。蒸馏是一种分离过程，其中利用液体混合物加热使挥发组分浓集于汽相，而较不挥发的组分则浓集于液相。部分冷凝是一种分离过程，其中利用蒸汽混合物的冷却使挥发组分浓集于汽相，从而使较不挥发的组分浓集于液相。精馏或连续蒸馏是一种分离过程，该过程将连续的部分蒸发和冷凝组合，如汽相和液相的逆流处理。汽相和液相的逆流接触是绝热的并包括各相之间的整体或局部接触。利用精馏原理分离混合物的分离过程装置经常通用地称为精馏塔，蒸馏塔或分馏塔。低温精馏是至少部分在150°K或更低的温度下进行的精馏过程。
术语“间接热交换”系指将两液流在相互之间无任何实际接触或流体相互混合的条件下发生的热交换关系。
本文所用之术语“填料”系指一定结构、尺寸和形状的实心或空心物体作为塔的内填物，以提供两相在逆流期间在液-汽界面使液体进行传质的表面积。
本文所用之术语“结构性填料”系指一类填料，其中各个填料块相互之间及相对于塔轴具有特定的定向关系。
本文所用之术语“氩塔系统”系指一种包括塔和顶部冷凝器的系统，该系统处理含氩的进料，并产生其氩浓度超过进料中之氩浓度的产品。
本文所用之术语“顶部冷凝器”系指使来自氩塔顶部的蒸汽液化的传热装置。
本文所用之术语“平衡级”系指蒸汽和液体之间的接触过程，经接触使出口的蒸汽流和液体流呈平衡状态。
通常本发明包括低压塔的改进方案，以便在氩塔顶部冷凝器进料和氩塔出料点之间(即通常在氩浓度最大点或稍低于此点)设置两个高度相等的结构性填料床，而且两床之间有液体的混合和再分配。对低压塔的改进提高结构性填料的传质性能，后者是在氩塔进料中达到含低水平氮的关键。有时，为防范填料床壁流的不良效应，将一块或多块板直接置于氩塔出料点之上。
在详细叙述之前将介绍对低压塔的改进，和叙述整体空气蒸馏/氩生产系统。
参看图1，洁净的压缩空气进料通过在热交换器12中与回流物流进行间接热交换而冷却，所得冷空气流14进入塔16，该塔为双塔系统之高压塔，其操作的绝对压力一般为70-95磅/平方英寸(psia)。部分进料空气流18经热交换器24，在其中用其加热排出的氧产品流。所得空气流26再进入塔28，该塔为双塔系统之低压塔，其操作压力低于高压塔之压力，一般其绝对压力为15-25psia。
在塔16中，进料空气被低温精馏分离为富氧液体和富氮蒸汽。富氧液体从塔16以液流30流出，部分经过热交换器32，所得物流34进入氩塔顶部冷凝器36，其中该物流经间接热交换而部分蒸发，同时冷凝氩塔顶部蒸汽。所得气体与富氧液流以物流38和40分别从顶部冷凝器36进入塔28。
富氮蒸汽以物流42从塔16流出并进入再沸器44，其中该物流经间接热交换而冷凝，同时沸腾塔28之底流。所得富氮液体分成物流48和物流50，前者返回塔16作回流，后者部分经过热交换器32，然后作为物流52进入塔28。
在塔28中，进入塔的各种进料流被低温精馏分离成精制的氮和氧。气态氧从塔28中的再沸器44之上以物流54流出。该物流再通过热交换器24，所得物流56经过热交换器12并作为气态氧产品流58回收。如果需要，液态氧物流60可从塔28的再沸器44区作为液态氧产品回收。产品氧通常的氧浓度至少为99.0％。
气态氮从塔28以物流62流出，经过热交换器32加热，所得物流66再经过热交换器12加热，并以气态氮产品流68回收，其中氧浓度一般低于百万分之10(ppm)。废物流70从塔28中氮产品流出点以下流出，经过热交换器32和12加热，并以物流72从系统中去除。此废物流可用来控制氮和氧产品流的产品纯度。
氩塔进料74至少含有5％的氩，优选至少含7％的氩和少于50ppm的氮，它与基本上其余的氧一起从塔28流出，并流入氩塔76，其中它被低温精馏分离为富氧液体和富氩蒸汽，后者基本不含氮。不含氮系指不超过10ppm氮。优选不超过5ppm氮，最优选不超过2ppm氮。富氧液体从塔76以物流78流出，并返回塔28。富氩蒸汽可直接从氩塔系统以不含氮的氩产品物流80回收。不含氮的产品氩亦可呈液体回收。此外，塔76可具有足够的分离级，使氩产品的氧含量低，即小于100ppm O2或优选10ppm O2。
部分氩塔蒸汽以物流82从塔76流出，并流入顶部冷凝器36，其中它经间接热交换而冷凝，同时部分蒸发富氧液体，正如前面所述。所得液体流84返回塔76作为回流。如果需要，并取决于氩塔进料74中的氮含量，物流82的一部分79可作为废氩物流去除，它可用来进一步减少产品氩中的氮浓度。
为了生产满足氮含量指标的氩产品，即典型氮含量为10ppm或更小，低水平氮可在低压塔28的区段100中，特别可在氩塔进料流74从塔28的流出点获得。如图2所示，如此低水平的氮通过设置结构性填料的分离床区段102和104来达到，优选两床高度相等，位置在氩塔冷凝器蒸汽进料38和氩塔料流74的流出点之间。此外，液体收集和再分配装置106位于结构性填料段102和104之中间点上，以实现中间点上液体的再分配。
从下面的讨论中可以明白，液体的混合和再分配对于获得氩塔进料中的预期低水平氮是一个关键因素。这种混合还可通过在下结构性填料段104的底部设置一块或多块板108而得到进一步提高。板108选用来减轻填料床104中任何塔壁流的负作用。板可用来混合所有下流的液体，并避免液体旁流的负作用，旁流可能引起塔壁流。然后进入氩塔76的进料流74从此板段的底部流出。
应该指出，塔段100由上进料点38和下出料点74确定，前者是从氩塔冷凝器38来的富氩蒸汽，后者则是进入氩塔76的蒸汽料流。从氩塔76来的富氧液体40通常在富氧蒸汽流38之上处加入低压塔28，但在某些情况下却在同一高度加入。此外，在某些情况下，部分富氧液流34可不经氩塔冷凝器直接加入低压塔。同样，一般愿将此液体在富氧蒸汽流38之上的高度上加入。
在近平衡窄点区操作的结构性填料塔段的分离性能会受液体分配不良的负影响。曾经确定，给定塔段性能对一定程度的液体不良分配的敏感性可在段区的某中间点混合塔中下流的液体来加以降低。将板用于在操作线和平衡线之间有窄点的塔段中的单填料床的底部，对消除窄点带来的敏感性具有普遍的效果，从而改善此塔段的性能。性能的改善是由于从填料床下流液体的混合造成的。混合可消除当液体分布偏离单向流时所形成的局部窄点。
因此，从低压塔28上面流下的液体被液体收集和分布装置110接收，来自氩塔冷凝器36的蒸汽可在该点进入低压塔28。液体再分配到上结构性填料段102，使下流液体和上行蒸汽之间进行充分和均匀的接触。但是，上结构性填料段102实际上并不完善，在填料中会发生某些不良液体分配，从而在塔28壁上产生某些沟流。用液体收集和分布装置106在段100的中点阻截液体会纠正液体的不良分配。
下结构性填料段104的高度与上结构性填料段102相等，其作用在于提供将氮浓度减少到预期水平所需的填料数量。
本发明令人满意的性能取决于将低压塔28的段100分成两个部分。液体在段100中不良分布的影响可用图3说明，该图是基于蒸馏系统的数学模型。图3表示段性能与较低的填料床104的理论塔板百分数之间的关系。图象表明将填料段100分成两个部分的效果和进入下段的液体的再混合和再分配的效果。
从图可以看出，如果液体的再混合只发生在段100的两个极端点，即顶部和底部上，则精馏性能相当不好。当再混合点从段100的底部上提，则分离效率得到改善，直致达到理论塔板数三分之一的水平。在这一水平上，整个填料段基本达到完全的理论分离性能。这种高水平性能一直延续到大约结构填料三分之二的高度，这时分离性能下降。这显示将结构性填料段分成性能基本相同的两个部分的合理性。但是，是否确准相等并不至关重要。从底部算起以三分之一到约三分之二的分段将得到接近理论的性能。
应该理解，上面的描述仅是本发明的一个例证。各种替代方案和改进方案可在不背离本发明的前提下可由本领域技术人员提出。因此，本发明意图是包括所有在所附权利要求范围内的替代、修正和变化。

Claims (8)

1.一种用于生产基本上不含有氮气的氩气(80)的低温气体蒸馏系统，它包括高压塔(16)、低压塔(28)和氩蒸馏塔(76)，该低压塔包括(i)用于接收来自顶部冷凝器(36)的富氧物流(38)的进料点，在该顶部冷凝器中氩塔蒸汽(82)通过与从所述高压塔排出的富氧液流(34)进行热交换而冷凝，所述冷凝的氩塔蒸汽(84)作为回流返回到所述氩塔，和(ii)为该氩塔提供进料物流的出料点，该低压塔还包括：位于该低压塔的进料点和出料点之间的第一结构性填料床(102)和第二结构性填料床(104)；其特征在于位于该进料点和该第一结构性填料床之间的液体收集和分配装置(110)，从而使从以上接收到的液流在其进入该第一结构性填料床之前进行再分配；位于该第一结构性填料床和该第二结构性填料床之间的液体收集和分配装置(106)，从而使从该第一结构性填料床流出的液流在其进入该第二结构性填料床之前进行再分配；位于该第二结构性填料床(104)和该出料点之间的收集和再分配液体的板装置(108)。
2.权利要求1所述之低温气体蒸馏系统，其中该液体收集和分配装置(106)包括液体收集和分配板。
3.权利要求1所述之低温气体蒸馏系统，其中该第一结构性填料床(102)和该第二结构性填料床(104)共包含X个理论塔板，而且其中该第二结构性填料床含该X个理论塔板的约三分之一到约三分之二，该第一结构性填料床含有该X个理论塔板的剩余部分。
4.权利要求1所述之低温气体蒸馏系统，其中该第一结构性填料床(102)和该第二结构性填料床(104)共含X个理论塔板，而且其中该第一结构性填料床和第二结构性填料床各含该X个理论塔板的约一半。
5.权利要求1所述之低温气体蒸馏系统，其中该出料点位于该低压塔(28)中约为最大氩浓度的点上。
6.一种生产基本上不含氮的氩(80)的方法，该方法借助于包含高压塔(16)、低压塔(28)和氩蒸馏塔(76)的低温气体蒸馏系统运行，该低压塔包括(i)用于接收来自顶部冷凝器(36)富氧液体(38)的进料点，在该顶部冷凝器中氩塔蒸汽(82)通过与从所述高压塔排出的富氧液流(34)进行热交换而冷凝，所述冷凝的氩塔蒸汽作为回流返回到所述氩塔，和(ii)向该氩塔提供进料流(74)的出料点，该方法包括以下步骤：
使工艺气体和该液体逆向流经第一结构性填料床(102)和第二结构性填料床(104)，上述床均位于该低压塔的进料点和出料点之间，其特征在于在该进料点和该第一结构性填料床之间的位置收集和分配该液体，能使从以上接收到的液流在其进入第一结构性填料床之前进行再分配；位于该第一结构性填料床和该第二结构性填料床之间的一点处收集和分配所述液体，从而能够对从该第一结构性填料床流出的液流在其进入该第二结构性填料床之前进行再分配；和通过板装置(108)对从该第二结构性填料床(104)流出的所述液体在其到达所述出料点之前进行收集和再分配。
7.权利要求6所述之方法，其中该第一结构性填料床(102)和该第二结构性填料床(104)共含X个理论塔板，而且其中该第二结构性填料床含该X个理论塔板的约三分之一到三分之二，而该第一结构性填料床含有该X个理论塔板的剩余部分。
8.权利要求6所述之方法，其中该第一结构性填料床(102)和该第二结构性填料床(104)共含X个理论塔板，而且其中第一结构性填料床和第二结构性填料床各含该X个理论塔板的约一半。
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US6128922A (en) * 1999-05-21 2000-10-10 The Boc Group, Inc. Distillation method and column
US6378332B1 (en) * 2000-09-07 2002-04-30 Praxair Technology, Inc. Packing with low contacting crimp pattern
US10663224B2 (en) * 2018-04-25 2020-05-26 Praxair Technology, Inc. System and method for enhanced recovery of argon and oxygen from a nitrogen producing cryogenic air separation unit
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DE1048936B (de) * 1957-08-31 1959-01-22 Adolf Messer G M B H Verfahren und Vorrichtung zur Gewinnung von stickstofffreiem Argon durch Tiefkuehlung und Rektifikation der Luft
US4499035A (en) * 1977-03-17 1985-02-12 Union Carbide Corporation Gas-liquid contacting tray with improved inlet bubbling means
CH617357A5 (zh) * 1977-05-12 1980-05-30 Sulzer Ag
US4836836A (en) * 1987-12-14 1989-06-06 Air Products And Chemicals, Inc. Separating argon/oxygen mixtures using a structured packing
US4813988A (en) * 1987-12-14 1989-03-21 Air Products And Chemicals, Inc. Suitable distillation column packing for the cryogenic separation of air
US4871382A (en) * 1987-12-14 1989-10-03 Air Products And Chemicals, Inc. Air separation process using packed columns for oxygen and argon recovery
DE69119731T2 (de) * 1990-12-17 1996-11-14 Air Liquide Luftdistillationskolonne mit einer Well-cross Packung
US5133790A (en) * 1991-06-24 1992-07-28 Union Carbide Industrial Gases Technology Corporation Cryogenic rectification method for producing refined argon
US5237823A (en) * 1992-03-31 1993-08-24 Praxair Technology, Inc. Cryogenic air separation using random packing
US5282365A (en) * 1992-11-17 1994-02-01 Praxair Technology, Inc. Packed column distillation system
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