CN111141110B - 一种低能耗中压氮气制取工艺 - Google Patents

一种低能耗中压氮气制取工艺 Download PDF

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CN111141110B
CN111141110B CN202010062916.5A CN202010062916A CN111141110B CN 111141110 B CN111141110 B CN 111141110B CN 202010062916 A CN202010062916 A CN 202010062916A CN 111141110 B CN111141110 B CN 111141110B
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韦霆
何森林
杨正军
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Hangzhou Turning Energy Technology Development Co ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • F25J3/04351—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using quasi-closed loop internal vapor compression refrigeration cycles, e.g. of intermediate or oxygen enriched (waste-)streams of nitrogen
    • F25J3/04357—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using quasi-closed loop internal vapor compression refrigeration cycles, e.g. of intermediate or oxygen enriched (waste-)streams of nitrogen and comprising a gas work expansion loop
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    • F25J3/04763—Start-up or control of the process; Details of the apparatus used
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    • F25J2270/00—Refrigeration techniques used
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Abstract

本发明公开一种低能耗中压氮气制取工艺，制取时所需装置，包括过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、电加热器、主换热器、低温冷冻机、精馏塔I、主冷凝蒸发器I、精馏塔II、主冷凝蒸发器II、增压透平膨胀机、增压透平膨胀机增压后冷却器、循环氮压机、循环氮压机后冷却器、液氮泵、过冷器。利用本发明工艺制取中压氮气，提取率高，装置能耗低。

Description

一种低能耗中压氮气制取工艺
技术领域
本发明涉及空气分离技术领域，具体涉及一种低能耗中压氮气制取工艺。
背景技术
随着化工、电子、新材料、瓷钢业、玻璃等行业技术发展和革新，对氮气需求量急速增加，同时对氮气纯度也提出了更高的要求。
目前市场上的常用的纯氮设备分为两种：单塔制氮和双塔制氮，单塔制氮流畅可制取一定压力的产品氮气直接供用户使用，该种流程形式虽然结构简单，但装置提取率较低，产品单耗高，不适合大规模用氮气量的需求；双塔制氮可以制取常压氮气或压力为0.1-0.2MpaG的低压氮气，装置提取率高，能耗较单塔制氮低，但是由于产品压力较低，不能直接满足用户对氮气压力的要求。
发明内容
本发明的目的是提供一种低能耗中压氮气制取工艺，以解决现有技术的不足。
本发明采用以下技术方案：
一种低能耗中压氮气制取工艺，制取时所需装置，包括过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、电加热器、主换热器、低温冷冻机、精馏塔I、主冷凝蒸发器I、精馏塔II、主冷凝蒸发器II、增压透平膨胀机、增压透平膨胀机增压后冷却器、循环氮压机、循环氮压机后冷却器、液氮泵、过冷器，
过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、电加热器、低温冷冻机、增压透平膨胀机增压端、增压透平膨胀机增压后冷却器、循环氮压机、循环氮压机后冷却器设于冷箱外，主换热器、精馏塔I、主冷凝蒸发器I、精馏塔II、主冷凝蒸发器II、增压透平膨胀机、液氮泵、过冷器设于冷箱内，主冷凝蒸发器I设于精馏塔I之上，主冷凝蒸发器II设于精馏塔II之上；
过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、主换热器依次连接，主换热器第一部分冷却出口和低温冷冻机连接，低温冷冻机和主换热器连接，主换热器第一完全冷却出口和精馏塔I底部的原料空气进口连接；
精馏塔I底部的液空出口和过冷器连接，过冷器和主冷凝蒸发器I连接，过冷器和主冷凝蒸发器I的连接管路上设有节流阀，主冷凝蒸发器I的富氧空气出口、主冷凝蒸发器I的液空出口均和精馏塔II底部连接；
精馏塔I顶部的压力氮气出口分别和主冷凝蒸发器I、主换热器连接，主冷凝蒸发器I的液氮出口和精馏塔I顶部连接；主换热器和循环氮压机连接，循环氮压机和循环氮压机后冷却器连接，循环氮压机后冷却器分别和外部中压氮气储罐、增压透平膨胀机增压端连接，增压透平膨胀机增压端和增压透平膨胀机增压后冷却器连接，增压透平膨胀机增压后冷却器和主换热器连接，主换热器第二部分冷却出口和低温冷冻机连接，低温冷冻机和主换热器连接，主换热器第三部分冷却出口、第二完全冷却出口分别和增压透平膨胀机、精馏塔I顶部连接，增压透平膨胀机和主换热器连接，主换热器连至循环氮压机；主换热器第二完全冷却出口和精馏塔I顶部的连接管路上设有节流阀；
精馏塔II底部的富氧液空出口和主冷凝蒸发器II连接，精馏塔II底部的富氧液空出口和主冷凝蒸发器II连接管路上设有节流阀；精馏塔II顶部的污氮气出口和过冷器连接，过冷器和主换热器连接，主换热器分别和外部放空管道、电加热器连接，电加热器和交替使用的分子筛吸附器连接；
精馏塔II顶部的氮气出口和主冷凝蒸发器II连接，主冷凝蒸发器II的液氮出口分别和液氮泵、外部的液氮储罐、精馏塔II顶部连接，液氮泵和精馏塔I顶部连接；
制取时包括如下步骤：
步骤一、将原料空气经过滤器过滤掉灰尘和机械杂质后，进入透平空气压缩机将空气压缩到设定压力；之后经空气预冷机组预冷后进入交替使用的分子筛吸附器中纯化；
步骤二、纯化后的原料空气部分用于仪表空气，其余部分进入主换热器部分冷却后抽出，经低温冷冻机冷却后引入主换热器继续冷却至饱和温度并带有一定的含湿后进入精馏塔I底部参与精馏；
步骤三、空气经精馏塔I精馏后分离为液空和压力氮气，液空经过冷器过冷、节流阀节流后进入主冷凝蒸发器I和压力氮气换热，液空被汽化为富氧空气，富氧空气和未被汽化的部分液空引入精馏塔II底部参与精馏；部分压力氮气引入主冷凝蒸发器I和液空换热，压力氮气被冷凝为液氮，液氮引入精馏塔I顶部作为回流液；
步骤四、富氧空气和液空经精馏塔II精馏后分离为富氧液空和氮气，富氧液空经节流阀节流后进入主冷凝蒸发器II和氮气换热，富氧液空被汽化为污氮气；氮气引入主冷凝蒸发器II和富氧液空换热，氮气被冷凝为液氮，部分液氮经液氮泵增压后进入精馏塔I顶部参与精馏，部分液氮作为产品液氮，其余液氮引入精馏塔II顶部作为回流液；
步骤五、精馏塔I顶部其余部分压力氮气经主换热器复热后出冷箱进入循环氮压机增压并冷却，冷却后的中压氮气引出部分作为中压氮气产品，其余经增压透平膨胀机增压端增压并冷却后进入主换热器，经部分冷却后引入低温冷冻机冷却，后引入主换热器继续冷却后抽出部分进入增压透平膨胀机膨胀，膨胀后氮气经主换热器复热后出冷箱进入循环氮压机循环，其余部分继续冷却至液化后节流进入精馏塔I顶部参与精馏；
步骤六、精馏塔II顶部引出的污氮气经过冷器、主换热器复热后出冷箱，部分作为再生气由电加热器加热后引入交替使用的分子筛吸附器，其余放空。
进一步地，步骤一空气经透平空气压缩机压缩到0.6-1.3MPa。
进一步地，步骤一空气经空气预冷机组预冷至5-8℃。
进一步地，步骤二其余部分空气进入主换热器部分冷却至243-252K后抽出，经低温冷冻机冷却至233-242K后引入主换热器继续冷却。
进一步地，步骤五其余中压氮气经增压透平膨胀机增压端增压并冷却后进入主换热器，经部分冷却至243-252K后引入低温冷冻机冷却至233-242K，后引入主换热器继续冷却至175-186K后抽出部分进入增压透平膨胀机膨胀。
进一步地，步骤五中压氮气产品压力为20-36bar，纯度为10ppmO2以下。
本发明的有益效果：
1、本发明采用双塔精馏，设置精馏塔II用于分离来自精馏塔I中分离出的富氧空气、液空中的氮，分离出的氮气经顶部主冷凝蒸发器II冷凝为液氮，部分液氮作为精馏塔II的回流液，部分液氮经液氮泵增压后引入精馏塔I作为回流液；精馏塔II的精馏作用分离出更多的氮产品，泵后液氮的回流增加精馏塔I的回流液，提高了精馏塔I的分离效果，从而有效提高了装置氮的提取率，降低装置能耗。
2、本发明采用双主冷凝蒸发器，设置主冷凝蒸发器I，因主冷凝蒸发器I中液空中含氧量较精馏塔II低，在精馏塔II精馏压力不变及满足主冷凝蒸发器I换热的情况下，可以降低精馏塔I的压力，从而降低进入精馏塔I的空气压力，进而降低装置能耗。
3、本发明工艺流程主冷凝蒸发器II中氮气冷凝后的液氮经液氮泵增压后再引入精馏塔I参与精馏，降低了装置的能耗。
4、本发明经增压透平膨胀机增压端增压后引出氮气经冷却节流的液氮，该股氮气压力高，经过主换热器被返流气体冷却时易液化，进一步降低装置能耗。
5、本发明从精馏塔I引出的为压力氮气，经过循环氮压机增压获得中压氮气产品，循环增压机进口压力高，压缩能耗低。
6、本发明增加低温冷冻机，低温冷冻机能效比高，可以提供低品位的冷能，降低主换热器的热负荷，降低能耗。
附图说明
图1为本发明工艺利用的装置的结构示意图。
具体实施方式
下面结合实施例和附图对本发明做更进一步地解释。下列实施例仅用于说明本发明，但并不用来限定本发明的实施范围。
一种低能耗中压氮气制取工艺，其是利用图1所示的装置进行制取。
所示装置包括过滤器1、透平空气压缩机2、空气预冷机组3、交替使用的分子筛吸附器4、电加热器5、主换热器6、低温冷冻机7、精馏塔I8、主冷凝蒸发器I9、精馏塔II10、主冷凝蒸发器II11、增压透平膨胀机12、增压透平膨胀机增压后冷却器13、循环氮压机14、循环氮压机后冷却器15、液氮泵16、过冷器17，过滤器1、透平空气压缩机2、空气预冷机组3、交替使用的分子筛吸附器4、电加热器5、低温冷冻机7、增压透平膨胀机12增压端、增压透平膨胀机增压后冷却器13、循环氮压机14、循环氮压机后冷却器15设于冷箱外，主换热器6、精馏塔I8、主冷凝蒸发器I9、精馏塔II10、主冷凝蒸发器II11、增压透平膨胀机12、液氮泵16、过冷器17设于冷箱内，主冷凝蒸发器I9设于精馏塔I8之上，主冷凝蒸发器II11设于精馏塔II10之上；
过滤器1、透平空气压缩机2、空气预冷机组3、交替使用的分子筛吸附器4、主换热器6依次连接，主换热器6第一部分冷却出口和低温冷冻机7连接，低温冷冻机7和主换热器6连接，主换热器6第一完全冷却出口和精馏塔I8底部的原料空气进口连接；
精馏塔I8底部的液空出口和过冷器17连接，过冷器17和主冷凝蒸发器I9连接，过冷器17和主冷凝蒸发器I9的连接管路上设有节流阀，主冷凝蒸发器I9的富氧空气出口、主冷凝蒸发器I9的液空出口均和精馏塔II10底部连接；
精馏塔I8顶部的压力氮气出口分别和主冷凝蒸发器I9、主换热器6连接，主冷凝蒸发器I9的液氮出口和精馏塔I8顶部连接；主换热器6和循环氮压机14连接，循环氮压机14和循环氮压机后冷却器15连接，循环氮压机后冷却器15分别和外部中压氮气储罐、增压透平膨胀机12增压端连接，增压透平膨胀机12增压端和增压透平膨胀机增压后冷却器13连接，增压透平膨胀机增压后冷却器13和主换热器6连接，主换热器6第二部分冷却出口和低温冷冻机7连接，低温冷冻机7和主换热器6连接，主换热器6第三部分冷却出口、第二完全冷却出口分别和增压透平膨胀机12、精馏塔I8顶部连接，增压透平膨胀机12和主换热器6连接，主换热器6连至循环氮压机14；主换热器6第二完全冷却出口和精馏塔I8顶部的连接管路上设有节流阀；
精馏塔II10底部的富氧液空出口和主冷凝蒸发器II11连接，精馏塔II10底部的富氧液空出口和主冷凝蒸发器II11连接管路上设有节流阀；精馏塔II10顶部的污氮气出口和过冷器17连接，过冷器17和主换热器6连接，主换热器6分别和外部放空管道、电加热器5连接，电加热器5和交替使用的分子筛吸附器4连接；
精馏塔II10顶部的氮气出口和主冷凝蒸发器II11连接，主冷凝蒸发器II11的液氮出口分别和液氮泵16、外部的液氮储罐、精馏塔II10顶部连接，液氮泵16和精馏塔I8顶部连接。
上述各部件的功能如下：
过滤器1，用于过滤原料空气中的灰尘和机械杂质；
透平空气压缩机2，用于将过滤后的原料空气压缩到设定压力；
空气预冷机组3，用于将过滤、压缩后的原料空气预冷；
交替使用的分子筛吸附器4，用于将过滤、压缩、预冷后的原料空气纯化，去除水分、CO2、C2H2等物质；
电加热器5，用于加热污氮气以再生交替使用的分子筛吸附器4；
主换热器6，用于将纯化后的原料空气、循环增压后的中压氮气冷却；用于将压力氮气、污氮气复热；
低温冷冻机7，用于主换热器6第一部分冷却出口、第二部分冷却出口的部分冷却空气冷却；
精馏塔I8，用于将原料空气精馏而分离为压力氮气和液空；
主冷凝蒸发器I9，用于压力氮气和液空换热，压力氮气被液化为液氮，液空被汽化为富氧空气；
精馏塔II10，用于将富氧空气和液空精馏而分离为氮气和富氧液空；
主冷凝蒸发器II11，用于氮气和富氧液空换热，氮气被液化为液氮，富氧液空被汽化为污氮气；
增压透平膨胀机12，用于将主换热器6第三部分冷却出口的部分冷却空气膨胀，制取冷量；
循环氮压机14，用于将经主换热器6复热后的压力氮气、经增压透平膨胀机12膨胀及主换热器6复热后的氮气循环增压；
液氮泵16，用于将主冷凝蒸发器II11的部分液氮增压；
过冷器17，用于液空过冷、污氮气过热。
具体制取时包括如下步骤：
步骤一、将原料空气经过滤器1过滤掉灰尘和机械杂质后，进入透平空气压缩机2将空气压缩到设定压力0.6-1.3MPa；之后经空气预冷机组3预冷至5-8℃后进入交替使用的分子筛吸附器4中纯化，去除水分、CO2、C2H2等物质；
步骤二、纯化后的原料空气部分用于仪表空气(图中未示意出)，其余部分进入主换热器6部分冷却至243-252K后抽出，经低温冷冻机7冷却至233-242K后引入主换热器6继续冷却至饱和温度并带有一定的含湿后进入精馏塔I8底部参与精馏；
步骤三、空气经精馏塔I8精馏后分离为液空和压力氮气，压力氮气压力为7-9.5bar；液空经过冷器17过冷、节流阀节流后进入主冷凝蒸发器I9和压力氮气换热，液空被汽化为富氧空气，富氧空气和未被汽化的部分液空引入精馏塔II10底部参与精馏；部分压力氮气引入主冷凝蒸发器I9和液空换热，压力氮气被冷凝为液氮，液氮引入精馏塔I8顶部作为回流液；
步骤四、富氧空气和液空经精馏塔II10精馏后分离为富氧液空和氮气，氮气压力为3-5bar；富氧液空经节流阀节流后进入主冷凝蒸发器II11和氮气换热，富氧液空被汽化为污氮气；氮气引入主冷凝蒸发器II11和富氧液空换热，氮气被冷凝为液氮，部分液氮经液氮泵16增压后进入精馏塔I8顶部参与精馏，部分液氮作为产品液氮，其余液氮引入精馏塔II10顶部作为回流液；
步骤五、精馏塔I8顶部其余部分压力氮气经主换热器6复热后出冷箱进入循环氮压机14增压并冷却，冷却后的中压氮气引出部分作为中压氮气产品，其压力为20-36bar，纯度为10ppmO2以下，其余经增压透平膨胀机12增压端增压并冷却后进入主换热器6，经部分冷却至243-252K后引入低温冷冻机7冷却至233-242K，后引入主换热器6继续冷却至175-186K后抽出部分进入增压透平膨胀机12膨胀，膨胀后氮气经主换热器6复热后出冷箱进入循环氮压机14循环，其余部分继续冷却至液化后节流进入精馏塔I8顶部参与精馏；
步骤六、精馏塔II10顶部引出的污氮气经过冷器17、主换热器6复热后出冷箱，部分作为再生气由电加热器5加热后引入交替使用的分子筛吸附器4，其余放空。

Claims (5)

1.一种低能耗中压氮气制取工艺，其特征在于，
制取时所需装置，包括过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、电加热器、主换热器、低温冷冻机、精馏塔I、主冷凝蒸发器I、精馏塔II、主冷凝蒸发器II、增压透平膨胀机、增压透平膨胀机增压后冷却器、循环氮压机、循环氮压机后冷却器、液氮泵、过冷器，
过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、电加热器、低温冷冻机、增压透平膨胀机增压端、增压透平膨胀机增压后冷却器、循环氮压机、循环氮压机后冷却器设于冷箱外，主换热器、精馏塔I、主冷凝蒸发器I、精馏塔II、主冷凝蒸发器II、增压透平膨胀机、液氮泵、过冷器设于冷箱内，主冷凝蒸发器I设于精馏塔I之上，主冷凝蒸发器II设于精馏塔II之上；
过滤器、透平空气压缩机、空气预冷机组、交替使用的分子筛吸附器、主换热器依次连接，主换热器第一部分冷却出口和低温冷冻机连接，低温冷冻机和主换热器连接，主换热器第一完全冷却出口和精馏塔I底部的原料空气进口连接；
精馏塔I底部的液空出口和过冷器连接，过冷器和主冷凝蒸发器I连接，过冷器和主冷凝蒸发器I的连接管路上设有节流阀，主冷凝蒸发器I的富氧空气出口、主冷凝蒸发器I的液空出口均和精馏塔II底部连接；
精馏塔I顶部的压力氮气出口分别和主冷凝蒸发器I、主换热器连接，主冷凝蒸发器I的液氮出口和精馏塔I顶部连接；主换热器和循环氮压机连接，循环氮压机和循环氮压机后冷却器连接，循环氮压机后冷却器分别和外部中压氮气储罐、增压透平膨胀机增压端连接，增压透平膨胀机增压端和增压透平膨胀机增压后冷却器连接，增压透平膨胀机增压后冷却器和主换热器连接，主换热器第二部分冷却出口和低温冷冻机连接，低温冷冻机和主换热器连接，主换热器第三部分冷却出口、第二完全冷却出口分别和增压透平膨胀机、精馏塔I顶部连接，增压透平膨胀机和主换热器连接，主换热器连至循环氮压机；主换热器第二完全冷却出口和精馏塔I顶部的连接管路上设有节流阀；
精馏塔II底部的富氧液空出口和主冷凝蒸发器II连接，精馏塔II底部的富氧液空出口和主冷凝蒸发器II连接管路上设有节流阀；精馏塔II顶部的污氮气出口和过冷器连接，过冷器和主换热器连接，主换热器分别和外部放空管道、电加热器连接，电加热器和交替使用的分子筛吸附器连接；
精馏塔II顶部的氮气出口和主冷凝蒸发器II连接，主冷凝蒸发器II的液氮出口分别和液氮泵、外部的液氮储罐、精馏塔II顶部连接，液氮泵和精馏塔I顶部连接；
制取时包括如下步骤：
步骤一、将原料空气经过滤器过滤掉灰尘和机械杂质后，进入透平空气压缩机将空气压缩到设定压力；之后经空气预冷机组预冷后进入交替使用的分子筛吸附器中纯化；
步骤二、纯化后的原料空气部分用于仪表空气，其余部分进入主换热器部分冷却后抽出，经低温冷冻机冷却后引入主换热器继续冷却至饱和温度并带有一定的含湿后进入精馏塔I底部参与精馏；
步骤三、空气经精馏塔I精馏后分离为液空和压力氮气，液空经过冷器过冷、节流阀节流后进入主冷凝蒸发器I和压力氮气换热，液空被汽化为富氧空气，富氧空气和未被汽化的部分液空引入精馏塔II底部参与精馏；部分压力氮气引入主冷凝蒸发器I和液空换热，压力氮气被冷凝为液氮，液氮引入精馏塔I顶部作为回流液；
步骤四、富氧空气和液空经精馏塔II精馏后分离为富氧液空和氮气，富氧液空经节流阀节流后进入主冷凝蒸发器II和氮气换热，富氧液空被汽化为污氮气；氮气引入主冷凝蒸发器II和富氧液空换热，氮气被冷凝为液氮，部分液氮经液氮泵增压后进入精馏塔I顶部参与精馏，部分液氮作为产品液氮，其余液氮引入精馏塔II顶部作为回流液；
步骤五、精馏塔I顶部其余部分压力氮气经主换热器复热后出冷箱进入循环氮压机增压并冷却，冷却后的中压氮气引出部分作为中压氮气产品，其余经增压透平膨胀机增压端增压并冷却后进入主换热器，经部分冷却至243-252K后引入低温冷冻机冷却至233-242K，后引入主换热器继续冷却至175-186K后抽出部分进入增压透平膨胀机膨胀，膨胀后氮气经主换热器复热后出冷箱进入循环氮压机循环，其余部分继续冷却至液化后节流进入精馏塔I顶部参与精馏；
步骤六、精馏塔II顶部引出的污氮气经过冷器、主换热器复热后出冷箱，部分作为再生气由电加热器加热后引入交替使用的分子筛吸附器，其余放空。
2.根据权利要求1所述低能耗中压氮气制取工艺，其特征在于，步骤一空气经透平空气压缩机压缩到0.6-1.3MPa。
3.根据权利要求1所述低能耗中压氮气制取工艺，其特征在于，步骤一空气经空气预冷机组预冷至5-8℃。
4.根据权利要求1所述低能耗中压氮气制取工艺，其特征在于，步骤二其余部分空气进入主换热器部分冷却至243-252K后抽出，经低温冷冻机冷却至233-242K后引入主换热器继续冷却。
5.根据权利要求1所述低能耗中压氮气制取工艺，其特征在于，步骤五中压氮气产品压力为20-36bar，纯度为10ppmO2以下。
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Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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CN114791205B (zh) * 2022-04-22 2023-07-21 杭州特盈能源技术发展有限公司 一种绿电高效转化低能耗空分储能及co2提纯液化工艺
CN115060041B (zh) * 2022-06-28 2024-04-05 四川空分集团工程有限公司 一种液空过冷返流膨胀双塔提产制氮系统及方法

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1038514A (zh) * 1988-06-08 1990-01-03 大连理工大学 生产高压氧和高压氮的空气分离流程
GB2269226B (en) * 1992-07-29 1996-01-31 Air Liquide Process and apparatus for the production of gaseous nitrogen
CN101048637A (zh) * 2004-11-08 2007-10-03 大阳日酸株式会社 氮制造方法和装置
CN101738059A (zh) * 2009-12-22 2010-06-16 四川空分设备(集团)有限责任公司 一种降低空气分离综合能耗的方法
CN103620330A (zh) * 2011-06-28 2014-03-05 大阳日酸株式会社 空气分离方法和装置
CN207716722U (zh) * 2018-01-12 2018-08-10 杭州特盈能源技术发展有限公司 一种新式带液氮泵低纯度富氧制取装置
CN109442867A (zh) * 2018-12-19 2019-03-08 杭州特盈能源技术发展有限公司 一种新型外增压内液化纯氮制取装置及方法
CN109838975A (zh) * 2019-03-22 2019-06-04 杭州特盈能源技术发展有限公司 一种低能耗液氮制取装置及工艺
CN110260594A (zh) * 2019-07-05 2019-09-20 浙江智海化工设备工程有限公司 一种产品氮气生产装置及其方法

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1038514A (zh) * 1988-06-08 1990-01-03 大连理工大学 生产高压氧和高压氮的空气分离流程
GB2269226B (en) * 1992-07-29 1996-01-31 Air Liquide Process and apparatus for the production of gaseous nitrogen
CN101048637A (zh) * 2004-11-08 2007-10-03 大阳日酸株式会社 氮制造方法和装置
CN101738059A (zh) * 2009-12-22 2010-06-16 四川空分设备(集团)有限责任公司 一种降低空气分离综合能耗的方法
CN103620330A (zh) * 2011-06-28 2014-03-05 大阳日酸株式会社 空气分离方法和装置
CN207716722U (zh) * 2018-01-12 2018-08-10 杭州特盈能源技术发展有限公司 一种新式带液氮泵低纯度富氧制取装置
CN109442867A (zh) * 2018-12-19 2019-03-08 杭州特盈能源技术发展有限公司 一种新型外增压内液化纯氮制取装置及方法
CN109838975A (zh) * 2019-03-22 2019-06-04 杭州特盈能源技术发展有限公司 一种低能耗液氮制取装置及工艺
CN110260594A (zh) * 2019-07-05 2019-09-20 浙江智海化工设备工程有限公司 一种产品氮气生产装置及其方法

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