CN110822811A - 具有集成氮气去除的天然气液化 - Google Patents

具有集成氮气去除的天然气液化 Download PDF

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CN110822811A
CN110822811A CN201910748400.3A CN201910748400A CN110822811A CN 110822811 A CN110822811 A CN 110822811A CN 201910748400 A CN201910748400 A CN 201910748400A CN 110822811 A CN110822811 A CN 110822811A
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stream
lng
nitrogen
heat exchanger
recycle
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CN110822811B (zh
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M.J.罗伯茨
陈飞
C.M.奥特
A.O.韦斯特
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Air Products and Chemicals Inc
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Air Products and Chemicals Inc
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    • F25J1/0002—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the fluid to be liquefied
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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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    • 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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    • 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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Abstract

一种具有集成的氮气去除的天然气液化方法和系统。再循环的LNG气体在与主要热交换器中的天然气流分开并联的回路中冷却。在加热束之后，冷却的再循环气体和天然气流被引导至氮气整流塔。循环流被引入天然气流上方的整流塔，并且至少一个分离级位于循环流入口和天然气入口之间的整流塔中。来自整流塔的底部流被引导到主要热交换器的冷却束，在那里它被过冷。

Description

具有集成氮气去除的天然气液化
背景技术
本申请涉及一种液化天然气进料流并从中除去氮气的方法。本申请还涉及用于液化天然气进料流并从中除去氮气的设备(例如天然气液化设备或其他形式的处理设施)。
在液化天然气的方法中，通常需要或必要的是，例如由于纯度和/或回收要求，从进料流中除去氮气同时使产物(甲烷)损失最小化。除去的氮产物可用作燃料气体或排放到大气中。如果用作燃料气体，氮气产物必须含有足够量的甲烷(通常大于30mol％)以保持其热值。在这种情况下，由于对氮气产物纯度的松散规范，氮气的分离并不困难，这要求使用除氮工艺，只需要最少的附加设备和功耗。然而，在由电动机驱动的许多中小型液化天然气(LNG)设施中，对燃料气体的需求非常小，并且氮气产物被排放到大气中。如果排气，由于环境问题和/或甲烷回收要求，氮气产物具有更严格的纯度规格，例如大于95摩尔％，在一些情况下大于99摩尔％。
在这种应用中，这种相对高的氮纯度要求带来了技术挑战和经济挑战。在天然气进料中氮气浓度非常高(通常大于10摩尔％，在某些情况下高达或甚至高于20摩尔％)的情况下，专用的氮气排出装置(NRU)可以提供一种强有力的方法来有效地去除氮气并产生纯的(大于99摩尔％)氮气产物。然而，有许多应用，其中天然气进料含有10mol％或更少的氮气。在这些应用中，由于高资本成本和设备复杂性，专用NRU通常是不可行的。此外，许多天然气进料中的氮气浓度经受相对大的波动这一事实决定了NRU能够适应氮气浓度的变化。
已经进行了一些尝试来解决这些挑战，包括向NRU添加氮循环流或使用专用的整流塔。然而，这些过程通常非常复杂，需要大量设备(具有相关的资金成本)，难以操作和/或效率低，特别是对于具有低氮气浓度的进料流(即小于5mol％)。此外，通常的情况是天然气进料中的氮气浓度会不时变化，这意味着即使人们正在处理目前氮气含量高的进料，也不能保证这仍然是该情况。
因此，需要一种简单、有效且成本有效的氮气去除方法，该方法能够从具有低氮气浓度和氮气浓度变化的天然气进料中除去氮气。
发明概述
下面概述了本发明的系统和方法的几个具体方面。
方面1:一种制备贫氮气LNG产物的方法，该方法包括：
(a)使天然气进料流通过主要热交换器的第一回路以冷却所述天然气进料流并使所述天然气流的至少一部分针对第一制冷剂液化，从而产生第一冷却的LNG流；
(b)从所述主要热交换器取出第一冷却的LNG流；
(c)膨胀所述第一冷却的LNG流以形成第一减压LNG流；
(d)在第一位置将所述第一减压LNG流引入氮气整流塔，所述第一位置位于所述氮气整流塔的底端；
(e)从所述氮气整流塔的底端取出第一LNG底部流；
(f)从所述氮气整流塔取出顶部流；
(g)冷却所述第一LNG底部流以产生过冷的LNG流；
(h)将所述过冷的LNG流的至少一部分引导至闪蒸罐或LNG储罐；
(i)收集选自来自所述闪蒸罐的闪蒸气体流和来自所述LNG储罐的蒸发气体流的组中的至少一种以形成循环流；
(j)使所述循环流通过所述主要热交换器的第二回路，以冷却所述循环流并使至少一部分循环流液化，从而产生至少部分液化的循环流；
(k)使所述至少部分液化的循环流膨胀以形成减压循环流；和
(l)在第二位置将所述减压循环流引入所述氮气整流塔，所述第二位置位于所述第一位置上方，并且至少一个分离级位于所述第一位置和所述第二位置之间的氮气整流塔中。
方面2:方面1的方法，还包括：
(m)使用所述过冷的液体LNG流为所述氮气整流塔提供冷却负荷。
方面3:方面2的方法，还包括：
(n)在执行步骤(m)之前至少部分地蒸发所述过冷的液体LNG流。
方面4:方面1-3中任一项的方法，还包括：
(o)压缩和冷却制冷回路中的第一制冷剂；
(p)取出所述第一制冷剂的滑流以向所述氮气整流塔提供冷却负荷。
方面5:方面1-4中任一项的方法，还包括：
(q)将所述过冷的LNG流的至少一部分引导至闪蒸罐。
方面6:方面1-5中任一项的方法，还包括：
(r)在执行步骤(j)之前压缩和冷却所述循环流。
方面7:方面1-6中任一项的方法，还包括：
(s)在执行步骤(b)之后和执行步骤(d)之前，通过针对来自所述氮气整流塔的底端的再沸流进行间接热交换，进一步冷却所述第一LNG流，从而产生加热的再沸流；
(t)将所述加热的再沸流引入所述氮气整流塔的底端中。
方面8:方面1-7中任一项的方法，其中步骤(h)还包括在氮气汽提塔中将所述过冷的液体LNG流分离成液体LNG产物流和蒸汽LNG产物流；并且该方法还包括:
(u)从所述氮气整流塔的上端取出富氮蒸汽流，使所述富氮蒸汽流通过位于所述氮气汽提塔的冷凝器热交换器，为所述氮气汽提塔提供沸腾负荷，这产生至少部分液化的富氮气流；和
(v)将所述至少部分液化的富氮气流返回到所述氮气整流塔的上端。
方面9:方面1-8中任一项的方法，还包括：
(w)在顶部热交换器中进一步冷却所述顶部流，并将进一步冷却的顶部流分离成富氮气流和富氢气/氦气流；
(x)膨胀所述富氮气流并使用膨胀的富氮气流为顶部热交换器提供制冷负荷。
方面10:方面1-9中任一项的方法，还包括：
(y)使用变压吸附或膜单元将所述顶部流分离成所述富氮气流和所述富氢气/氦气流。
方面11:方面1-10中任一项的方法，还包括：
(z)将所述过冷的LNG流分离成LNG产物流和蒸汽NG产物流；
其中步骤(i)还包括将所述LNG产物流引导至所述LNG储罐。
方面12:方面11的方法，还包括：
(aa)将所述蒸发气体流与所述蒸汽NG产物流组合以形成循环流。
方面13:方面1-12中任一项的方法，其中步骤(d)包括将所述第一减压LNG流引入第一位置的氮气整流塔，所述第一位置位于位于所述氮气整流塔内的任何分离级下方。
方面14:方面1-13中任一项的方法，还包括：
(ab)将滑流从所述天然气进料流引导到所述氮气整流塔的底端。
方面15:一种用于产生贫氮气LNG产物的设备，该设备包括:
主要热交换器，具有第一组冷却通道，用于接收天然气进料流并使所述流通过热交换器以冷却天然气进料流并液化至少一部分天然气进料流，以产生第一LNG流和过冷的LNG流，所述主热交换器还包括第二组通道，用于接收循环流并使所述循环流通过所述主要热交换器以冷却和至少部分地液化循环流以产生第一至少部分液化的循环流，其中所述冷却通道被布置为使所述循环流通过与天然气进料流分开并平行的热交换器；
制冷系统，用于向所述主要热交换器供应制冷剂，以冷却所述第一和第二组冷却通道；
第一分离系统，与所述主要热交换器流体流动连通，用于接收、膨胀、部分蒸发和分离所述第一LNG流，或由第一LNG流的一部分形成的LNG流，以形成底部流和顶部流，所述第一分离系统包括循环流入口和位于所述循环流入口上方的LNG流入口，所述第一分离系统还包括位于所述循环流入口和所述LNG流入口之间的至少一个分离级；和
储罐，用于接收和储存所述过冷的LNG流，所述储罐与所述循环流流体流动连通；
其中所述底部流与所述主要热交换器的冷却束中的第一组通道流体流动连通，该主要热交换器的冷却束可操作地配置为使所述底部流过冷以形成过冷的LNG流，
方面16:方面15的系统，还包括压缩机，用于接收来自所述储罐的循环流并压缩所述循环流以形成压缩的循环流并将压缩的循环流返回到所述主要热交换器。
方面17:方面15-16中任一项的系统,其中所述第一分离系统还包括冷凝器热交换器，其适于使用所述过冷的LNG流来向所述第一分离系统提供冷凝负荷。
方面18:方面17的系统，还包括位于所述冷凝器热交换器下游和所述储罐上游的闪蒸罐。
附图简述
下面将结合附图描述本发明，其中相同的数字表示相同的元件。
图1是具有专用除氮系统的天然气液化系统的第一示例性实施例的框图；
图2是具有专用除氮系统的天然气液化系统的第二示例性实施例的框图；
图3是具有专用除氮系统的天然气液化系统的第三示例性实施例的框图；
图4是具有专用除氮系统的天然气液化系统的第四示例性实施例的框图；
图4A是图4所示系统的可选变型的方框图；
图5是具有专用除氮系统的天然气液化系统的第五示例性实施例的框图；
图6是具有专用除氮系统的天然气液化系统的第六示例性实施例的框图；
图7是具有专用脱氮系统的天然气液化系统的第七示例性实施例的框图。
发明详述
随后的详细描述仅提供了优选的示例性实施例，并且不旨在限制本发明的范围、适用性或配置。而是，随后对优选示例性实施例的详细描述将为本领域技术人员提供用于实现本发明的优选示例性实施例的可行描述。应当理解，在不脱离如所附权利要求中阐述的本发明的精神和范围的情况下，可以对元件的功能和布置进行各种改变。
在说明书和权利要求书中可以使用方向术语来描述本发明的部分(例如，上、下、左、右等)。这些方向术语仅旨在帮助描述示例性实施例，并且不旨在限制要求保护的发明的范围。如本文所用，术语“上游”旨在表示与导管中的流体从参考点的流动方向相反的方向。类似地，术语“下游”旨在表示在与从参考点的管道中的流体的流动方向相同的方向上。
在说明书和权利要求中使用的术语“流体流动通信”是指两个或更多个部件之间的连接性质，其使液体、蒸汽和/或气体能够以包含的方式在部件之间传输(即，没有实质性泄漏)。将两个或更多个部件联接使得它们彼此流动连通可以涉及本领域已知的任何合适的方法，例如使用焊接、法兰导管、垫圈和螺栓。两个或更多个组件也可以经由系统的其他组件耦合在一起，这些组件可以将它们分开。
在说明书和权利要求书中使用的术语“天然气”是指主要由甲烷组成的烃类气体混合物。
在说明书和权利要求书中使用的术语“分离级”旨在表示一种汽-液接触装置，其能够在上升的蒸汽和下降的液体之间进行质量传递，使得蒸汽离开装置与液体平衡。汽液接触装置的实例包括工业上通常已知的任何类型的装置，例如托盘(阀托盘、筛盘等)或填料(规整填料、无规填料等)。
如说明书和权利要求书中所使用的术语“束”旨在表示线圈缠绕热交换器的一部分，其包括壳体和至少一个缠绕管路。
如说明书和权利要求书中所用的术语“轻质组分”意指具有低于甲烷的标准沸点的流体组分。
在本公开中，在实施例之间共享的元件由增加因子100的附图标记表示。例如，图2中的闪蒸罐240对应于图5中的闪蒸罐540。为了清楚起见，与先前实施例共享的实施例的一些特征在随后的附图中编号，但在说明书中不再重复。如果在随后的实施例中没有具体描述编号的特征，则可以假设该特征在结构上基本相同并且执行与描述特征的最后实施例中的基本相同的功能。
图1中示出了天然气液化系统100的第一示例性实施例。天然气(NG)进料102与包含蒸发气体(BOG)和/或闪蒸气体的循环流166组合以形成在加热束106中冷却的组合的NG/BOG流103以产生冷却的NG/BOG流105。冷却的NG/BOG流105在中间束110中至少部分地液化以产生至少部分液化的NG流107。至少部分液化的NG流107通过阀114降压以产生减压NG流109，其进入所有分离级117下方的氮(N2)整流塔118的底端。
来自N2整流塔118的底部液体流120耗尽轻组分并继续在冷却束122中过冷以制备过冷的LNG流124。过冷的LNG流124进入冷凝器热交换器126以为N2整流塔118提供冷却任务。离开冷凝器热交换器126的LNG流134通过阀136降低压力以产生第一减压LNG流138，其可选地在闪蒸罐140中进一步降低压力以产生顶部LNG流150和底部LNG产物142。
来自闪蒸罐140的底部LNG产物142经由管线146和阀144被送至LNG储罐148。LNG产物可通过管线199从储罐148排出。来自闪蒸罐140的顶部LNG流150通过经由管线154与来自LNG储罐148的BOG气流156组合的阀152减压以形成循环流158。循环流158优选在BOG压缩机160中压缩以形成压缩的循环流162，压缩的循环流162然后优选在空气冷却器164中冷却以产生BOG循环流166，BOG循环流166与天然气进料102结合以形成组合的NG/BOG流103。
从N2整流塔118的上端(在部分冷凝器126上方)取出富含轻组分如N2、H2和He的塔顶部流128，并用作燃料或通过阀门130和管线132排放到大气中。
系统100包括制冷系统199，其为加热束106、中间束110和冷却束122提供制冷负荷。图1所示的制冷系统是示例性的闭环系统，其中制冷剂在专用回路中在每束中冷却，然后膨胀并引入每个束的壳侧，以为天然气提供制冷负荷。制冷剂从加热束的壳侧的底部抽出，并在再循环到束之前被压缩和冷却。可以使用任何合适的制冷系统或过程代替本文所述的任何实施例中的系统199。为了简化附图，制冷系统199未在图2至7中示出，但应理解为是每个示例性液化系统的一部分。
系统200的第二示例性实施例在图2中示出。除了处理顶部流228之外，该实施例与图1的系统100几乎相同。在系统200中，N2整流塔218的顶部流228经由阀230和管线232传送到热交换器268，在那里它进一步冷却成冷却的顶部流270。然后将冷却的顶部流270在闪蒸罐278中相分离以产生富含H2/He的流280和富含N2的流276。富含N2的流276通过阀274降压以产生减压N2富集流272，其被送至热交换器268以在排放到大气284之前提供制冷。富含H2/He的流280在通过管线282转移到H2循环系统(未示出)之前，任选地将其送至交换器268以提供制冷。
系统200中来自图1的系统100的另一个变化是阀225的定位。在该系统200中，通过阀225减小过冷的LNG流224的压力，以产生减压过冷的LNG流227，然后将其引入冷凝器热交换器226中。
系统300的第三示例性实施例在图3中示出。在图3中，天然气进料302与循环流358分开冷却。天然气进料302首先在加热束306中冷却以产生冷却的NG流308并且至少部分地在中间束310中液化以产生至少部分液化的NG流312。至少部分液化的NG流312通过阀314降低压力以产生减压NG流316，其进入N2整流塔318。来自N2整流塔318的底部液体流320耗尽轻组分并继续在冷却束322中过冷以产生过冷的LNG流324。过冷的LNG流324进入冷凝器热交换器326，以向N2整流塔318提供冷却负荷。离开冷凝器热交换器326的LNG流334通过阀336进一步降低压力以产生第一减压LNG流338，其任选地在闪蒸罐340中进一步降低压力以产生顶部NG流350和底部LNG产物342。
来自闪蒸罐340的底部LNG产物342经由管线346和阀344被送到LNG储罐348。闪蒸罐340的顶部350经由阀352和管线354引导以与来自LNG储罐348的BOG气体356结合以制备循环流358。循环流358在BOG压缩机360中压缩以形成压缩的循环流362，然后在空气冷却器364中冷却压缩的循环流362以产生BOG循环流366。
在该实施方案中，循环流366至少部分地与加热束306和中间束310中的天然气进料流302并行地液化，以产生至少部分液化的循环流388。至少部分液化的循环流388通过阀392降压以产生减压循环流390。减压循环流390在高于引入流316的位置的位置处引入N2整流塔318中，在这两个位置之间存在至少一个分离级317。
与图2的系统200类似地处理富含轻组分如N2、H2和He的N2整流塔顶部328。
图4中示出了系统400的第四示例性实施例。在该实施例中，至少部分液化的NG流412在再沸器热交换器497中进一步冷却，以产生进一步冷却的、部分液化的NG流413。进一步冷却的部分液化的NG流413通过阀414降低压力以产生减压部分液化的LNG流416。如图3的系统300中那样，减压部分液化的LNG流416在一组分离级417上方的位置处进入N2整流塔418。
再沸器热交换器497经由管线496和返回管线498向N2整流塔418的底部提供加热负荷。来自N2整流塔418的底部液体流420耗尽轻组分并继续在冷却束422中过冷却以产生过冷的LNG流424。过冷的LNG流424进入冷凝器热交换器426以向N2整流塔418提供冷却负荷。
离开冷凝器热交换器426的LNG流434通过阀436进一步降低压力以产生第一减压LNG流438，其可选地在闪蒸罐440中进一步降低压力以产生顶部LNG流450和底部LNG产物442。来自闪蒸罐440的底部LNG产物442经由管线446被送到LNG储罐440，并且如果需要，通过泵444泵送。
系统400的可选变型在图4A中示出。在图4A中，第一减压LNG流438通过阀436减压并且经由管线454被引导至LNG储罐448，而不是在闪蒸罐中进一步分离。
系统500的第五示例性实施例在图5中示出。在图5中，过冷的LNG流524进入N2汽提塔525的顶部，并向位于N2汽提塔525内的冷凝器热交换器526提供冷凝冷却负荷。第二顶部流547从N2整流塔518的上端排出，并在冷凝器热交换器526中冷凝，以产生至少部分液化的富氮气流545，其再次引入N2整流塔518的上端。
来自N2汽提塔525的底部LNG产物537被送至LNG储罐548。N2汽提塔525的顶部流527经由阀529和管线531输送以与来自储罐的BOG气体533结合以产生循环流558。
任选地，可以使用温进料气体的滑流，例如流505和/或流509，以向N2整流塔511的底部提供额外的汽提和再沸腾作用。
系统600的第六示例性实施例在图6中示出。该实施例与系统300非常相似，不同之处在于N2整流塔618的部分冷凝器626的冷却负荷不是由LNG提供，而是由来自制冷回路的制冷剂流665的滑流提供(参见例如图1)。离开N2整流塔618的废制冷剂667返回制冷回路。
在该实施方案中，富含H2/He的流676不通过热交换器668传输，这简化了其结构。
图7中示出了系统700的第七示例性实施例。在图7中，N2整流塔顶部728经由阀730和管线732传输，以在变压吸附(PSA)单元或膜单元767中进一步处理以进一步将H2/He与N2分离。
实施例
该实施例基于图3的系统300的具体示例性实施方式。来自煤气化单元的天然气进料流302进入加热束306并在热交换器的壳侧使用混合制冷剂(未示出)在管回路中冷却至-32华氏度(-35℃)。然后使用中间束310中的混合制冷剂进一步冷却冷却的NG流308至-163华氏度(-108℃)，以形成至少部分液化的NG流312。至少部分液化的NG流312通过阀314减压至323PSIA(2227kPa)，形成减压NG流316(其为两相)。将减压NG流316引入N2整流塔318的底端并在N2整流塔318的底端分离。所得蒸气与减压循环流390的蒸气部分一起通过N2整流塔盘或填料(分离级)并逐步纯化(除去甲烷)，得到含有约0.5mol％甲烷的顶部流328。
顶部流328可用作工艺加热或其他用途的燃料。在该实例中，使用热交换器368和分离器378进一步分离顶部流328。顶部流328经由阀330和管线332引导至热交换器368，在那里将其冷却至-274华氏度(-170摄氏度)。该冷却冷凝氮气和较重的组分，其在滚筒378中分离以产生粗氢气流380和氮气液流376。然后氮气液流376在阀374处减压并且减压流372在热交换器368中蒸发，并以流384的形式排放到大气中。粗氢气流380也在热交换器368中加热，然后作为流382再循环到煤气化设备中。
表1
Figure BDA0002166344810000101
Figure BDA0002166344810000111
进入N2整流塔318的大部分进料在底部液体流320中回收。然后底部液体流320在冷却束322中过冷，作为过冷的LNG流324在-263华氏度的温度下离开(-164摄氏度)。过冷的LNG流324的压力降低至18psia(124kPa)并在冷凝器热交换器326中部分蒸发，以向N2整流塔318提供制冷。离开冷凝器热交换器326的LNG流334是5％摩尔蒸气分数并且被送到闪蒸罐340，在那里它被分离到底部LNG产物342，其被送到LNG储罐348和顶部NG流350。LNG储罐348中的LNG在大气压--14.7psia(101kPa)下储存。LNG储罐348产生液体LNG流399和蒸发气体流356，其由当来自闪蒸罐340的液体流342经由连接管线346进入LNG储罐348并且由于热量泄漏到LNG储罐348中而沸腾时产生额外的闪蒸产生。
来自闪蒸罐340的顶部NG流350与来自LNG储罐348的BOG流356组合，形成循环流358，其被送至BOG压缩机360。BOG压缩机360将循环流358压缩至887psia(6116kPa)，形成压缩的循环流362。然后将压缩的循环流362在空气冷却器364中冷却至100华氏度(38℃)，形成BOG循环流366。BOG循环流366进入加热束306并在管回路中冷却至-32华氏度(-36℃)，以抵抗通过热交换器(未示出)的壳侧下降的混合制冷剂。然后将得到的流386在中间束310中进一步冷却至-163华氏度(-108℃)。将得到的流312通过阀门392减压至320psia(2206kPa)，形成引入N2整流塔318的减压循环流390。
虽然上面已经结合优选实施例描述了本发明的原理，但是应该清楚地理解，该描述仅通过示例的方式进行，而不是作为对本发明范围的限制。

Claims (18)

1.一种制备贫氮气LNG产物的方法，该方法包括：
(a)使天然气进料流通过主要热交换器的第一回路以冷却所述天然气进料流并使所述天然气流的至少一部分针对第一制冷剂液化，从而产生第一冷却的LNG流；
(b)从所述主要热交换器取出第一冷却的LNG流；
(c)膨胀所述第一冷却的LNG流以形成第一减压LNG流；
(d)在第一位置将所述第一减压LNG流引入氮气整流塔，所述第一位置位于所述氮气整流塔的底端；
(e)从所述氮气整流塔的底端取出第一LNG底部流；
(f)从所述氮气整流塔取出顶部流；
(g)冷却所述第一LNG底部流以产生过冷的LNG流；
(h)将所述过冷的LNG流的至少一部分引导至闪蒸罐或LNG储罐；
(i)收集选自来自所述闪蒸罐的闪蒸气体流和来自所述LNG储罐的蒸发气体流的组中的至少一种以形成循环流；
(j)使所述循环流通过所述主要热交换器的第二回路，以冷却所述循环流并使至少一部分循环流液化，从而产生至少部分液化的循环流；
(k)使所述至少部分液化的循环流膨胀以形成减压循环流；和
(l)在第二位置将所述减压循环流引入所述氮气整流塔，所述第二位置位于所述第一位置上方，并且至少一个分离级位于所述第一位置和所述第二位置之间的氮气整流塔中。
2.权利要求1所述的方法，还包括：
(m)使用所述过冷的液体LNG流为所述氮气整流塔提供冷却负荷。
3.权利要求2所述的方法，还包括：
(n)在执行步骤(m)之前至少部分地蒸发所述过冷的液体LNG流。
4.权利要求1所述的方法，还包括：
(o)压缩和冷却制冷回路中的第一制冷剂；
(p)取出所述第一制冷剂的滑流以向所述氮气整流塔提供冷却负荷。
5.权利要求1所述的方法，还包括：
(q)将所述过冷的LNG流的至少一部分引导至闪蒸罐。
6.权利要求1所述的方法，还包括：
(r)在执行步骤(j)之前压缩和冷却所述循环流。
7.权利要求1所述的方法，还包括：
(s)在执行步骤(b)之后和执行步骤(d)之前，通过针对来自所述氮气整流塔的底端的再沸流进行间接热交换，进一步冷却所述第一LNG流，从而产生加热的再沸流；
(t)将所述加热的再沸流引入所述氮气整流塔的底端中。
8.权利要求1所述的方法，其中步骤(h)还包括在氮气汽提塔中将所述过冷的液体LNG流分离成液体LNG产物流和蒸汽LNG产物流；并且该方法还包括：
(u)从所述氮气整流塔的上端取出富氮蒸汽流，使所述富氮蒸汽流通过位于所述氮气汽提塔的冷凝器热交换器，为所述氮气汽提塔提供沸腾负荷，这产生至少部分液化的富氮气流；和
(v)将所述至少部分液化的富氮气流返回到所述氮气整流塔的上端。
9.权利要求1所述的方法，还包括：
(w)在顶部热交换器中进一步冷却所述顶部流，并将进一步冷却的顶部流分离成富氮气流和富氢气/氦气流；
(x)膨胀所述富氮气流并使用膨胀的富氮气流为顶部热交换器提供制冷负荷。
10.权利要求1所述的方法，还包括：
(y)使用变压吸附或膜单元将所述顶部流分离成所述富氮气流和所述富氢气/氦气流。
11.权利要求1所述的方法，还包括：
(z)将所述过冷的LNG流分离成LNG产物流和蒸汽NG产物流；
其中步骤(i)还包括将所述LNG产物流引导至所述LNG储罐。
12.权利要求11所述的方法，还包括：
(aa)将所述蒸发气体流与所述蒸汽NG产物流组合以形成循环流。
13.权利要求1所述的方法，其中步骤(d)包括将所述第一减压LNG流引入第一位置的氮气整流塔，所述第一位置位于位于所述氮气整流塔内的任何分离级下方。
14.权利要求1所述的方法，还包括：
(ab)将滑流从所述天然气进料流引导到所述氮气整流塔的底端。
15.一种用于制备贫氮气LNG产物的设备，该设备包括：
主要热交换器，具有第一组冷却通道，用于接收天然气进料流并使所述流通过热交换器以冷却天然气进料流并液化至少一部分天然气进料流，以产生第一LNG流和过冷的LNG流，所述主热交换器还包括第二组通道，用于接收循环流并使所述循环流通过所述主要热交换器以冷却和至少部分地液化循环流以产生第一至少部分液化的循环流，其中所述冷却通道被布置为使所述循环流通过与天然气进料流分开并平行的热交换器；
制冷系统，用于向所述主要热交换器供应制冷剂，以冷却所述第一和第二组冷却通道；
第一分离系统，与所述主要热交换器流体流动连通，用于接收、膨胀、部分蒸发和分离所述第一LNG流，或由第一LNG流的一部分形成的LNG流，以形成底部流和顶部流，所述第一分离系统包括循环流入口和位于所述循环流入口上方的LNG流入口，所述第一分离系统还包括位于所述循环流入口和所述LNG流入口之间的至少一个分离级；和
储罐，用于接收和储存所述过冷的LNG流，所述储罐与所述循环流流体流动连通；
其中所述底部流与所述主要热交换器的冷却束中的第一组通道流体流动连通，该主要热交换器的冷却束可操作地配置为使所述底部流过冷以形成过冷的LNG流。
16.权利要求15所述的系统，还包括压缩机，用于接收来自所述储罐的循环流并压缩所述循环流以形成压缩的循环流并将压缩的循环流返回到所述主要热交换器。
17.权利要求15所述的系统，其中所述第一分离系统还包括冷凝器热交换器，其适于使用所述过冷的LNG流来向所述第一分离系统提供冷凝负荷。
18.权利要求17所述的系统，还包括位于所述冷凝器热交换器下游和所述储罐上游的闪蒸罐。
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101163934A (zh) * 2005-04-22 2008-04-16 气体产品与化学公司 从液化天然气中两段去除氮
CN101993749A (zh) * 2009-08-21 2011-03-30 林德股份公司 用于从天然气分离氮气的方法
CN102084199A (zh) * 2007-06-19 2011-06-01 气体产品与化学公司 脱氮气塔再沸器构造
CN102767936A (zh) * 2012-07-18 2012-11-07 重庆耐德工业股份有限公司 含氮天然气中氮-甲烷分离生产气相天然气以及液相天然气的工艺
WO2013087569A2 (en) * 2011-12-12 2013-06-20 Shell Internationale Research Maatschappij B.V. Method and apparatus for removing nitrogen from a cryogenic hydrocarbon composition
CN105043014A (zh) * 2014-04-24 2015-11-11 气体产品与化学公司 使用专用再喷射回路的液化天然气生产中的集成的除氮
CN211400511U (zh) * 2018-08-14 2020-09-01 气体产品与化学公司 用于制备贫氮气液化天然气产物的设备

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3440828A (en) * 1966-02-11 1969-04-29 Air Prod & Chem Liquefaction of natural gas employing cascade refrigeration
DE2022954C3 (de) * 1970-05-12 1978-05-18 Linde Ag, 6200 Wiesbaden Verfahren zur Zerlegung von stickstoffhaltigem Erdgas
US4225329A (en) * 1979-02-12 1980-09-30 Phillips Petroleum Company Natural gas liquefaction with nitrogen rejection stabilization
FR2826969B1 (fr) 2001-07-04 2006-12-15 Technip Cie Procede de liquefaction et de deazotation de gaz naturel, installation de mise en oeuvre, et gaz obtenus par cette separation
AU2007286291B2 (en) 2006-08-14 2010-08-12 Shell Internationale Research Maatschappij B.V. Method and apparatus for cooling a hydrocarbon stream
DE102009015766A1 (de) 2009-03-31 2010-10-07 Linde Aktiengesellschaft Verfahren zum Verflüssigen einer Kohlenwasserstoff-reichen Fraktion
KR20120040700A (ko) * 2009-07-21 2012-04-27 쉘 인터내셔날 리써취 마트샤피지 비.브이. 다상 탄화수소 스트림을 처리하는 방법 및 이를 위한 장치
DE102011010633A1 (de) * 2011-02-08 2012-08-09 Linde Ag Verfahren zum Abkühlen eines ein- oder mehrkomponentigen Stromes
JP6338589B2 (ja) 2012-11-16 2018-06-06 エクソンモービル アップストリーム リサーチ カンパニー 天然ガスの液化
US20160258675A1 (en) * 2013-10-09 2016-09-08 Lummus Technology Inc. Split feed addition to iso-pressure open refrigeration lpg recovery
US20150308737A1 (en) 2014-04-24 2015-10-29 Air Products And Chemicals, Inc. Integrated Nitrogen Removal in the Production of Liquefied Natural Gas Using Intermediate Feed Gas Separation
US9945604B2 (en) 2014-04-24 2018-04-17 Air Products And Chemicals, Inc. Integrated nitrogen removal in the production of liquefied natural gas using refrigerated heat pump
CN104293404B (zh) * 2014-09-12 2016-08-24 成都深冷液化设备股份有限公司 一种天然气高效脱氮的装置及其方法
US9863697B2 (en) * 2015-04-24 2018-01-09 Air Products And Chemicals, Inc. Integrated methane refrigeration system for liquefying natural gas
US10024595B2 (en) 2016-09-21 2018-07-17 Praxair Technology, Inc. System and method for cryogenic purification of a feed stream comprising hydrogen, methane, nitrogen and argon

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101163934A (zh) * 2005-04-22 2008-04-16 气体产品与化学公司 从液化天然气中两段去除氮
CN102084199A (zh) * 2007-06-19 2011-06-01 气体产品与化学公司 脱氮气塔再沸器构造
CN101993749A (zh) * 2009-08-21 2011-03-30 林德股份公司 用于从天然气分离氮气的方法
WO2013087569A2 (en) * 2011-12-12 2013-06-20 Shell Internationale Research Maatschappij B.V. Method and apparatus for removing nitrogen from a cryogenic hydrocarbon composition
CN102767936A (zh) * 2012-07-18 2012-11-07 重庆耐德工业股份有限公司 含氮天然气中氮-甲烷分离生产气相天然气以及液相天然气的工艺
CN105043014A (zh) * 2014-04-24 2015-11-11 气体产品与化学公司 使用专用再喷射回路的液化天然气生产中的集成的除氮
CN211400511U (zh) * 2018-08-14 2020-09-01 气体产品与化学公司 用于制备贫氮气液化天然气产物的设备

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