552391 五、 發明說明 ( 1； ) 本 發 明 關 於 — 種 在精餾 系 統 中 藉 由 低 溫 分餾 空 氣 以 製 造 氮 氣 之 方 法 該 系 統具有 壓 力 柱 及 低 壓 柱 ，該 方 法 中 進 料 空 氣 被 導 入 壓 力 柱 內。含 氧 的 液 體 餾 份 由 壓力 柱 被 移 出 然 後 送 入 低 壓 柱 內 Ο 氣態氮 係 由 質 量 傳 遞 段 上方 的低 壓 柱 被 抽取 出 其 具 有 至 少一個 理 三A 刪 板 或 實 際 板 ，且 該 氣 態 氮 在 頂 部 冷 凝 器 中 藉 與 冷凍劑 作 間 接 熱 交 換 而 至少 部 分 被 冷 凝 〇 局 純 度 氮 係 由 質 量傳遞 段 下 方 的 低 壓 柱 被移 出 且 係 以 氮 產 物 被 獲 得 〇 本 發 明 爲 以 導 言 中所述 類 型 的 方 法 之 以 及對 應 的 經 濟 上 特別有利 之 裝 置 爲 基礎當 作 巨 的 0 藉 由 以 下 事 實 來 達成此 巨 的 • 該 方 法 具 有冷 凍 供 應 系 統 1 其 中 冷 凍 流 體 流 動著， 且 來 白 冷 凍 供 應 系統 的 冷凍 流 體 被 導 入 質 量 傳 遞 段 上方的 低 壓 柱 內 〇 作 爲 替代例 或 附加 地 在 本 發 明 的 上 下文中 來 白 冷凍供 應 系統 的 冷凍流 體 亦 可 以 被 導 入 壓 力 柱的上 部 區 域 內 〇 在本 發 明 中 5 可 利用容 易 取 得 的 媒 質 來形成 被 導 入 低 壓 柱 內 的 冷凍 流 體 此製程 牽 涉低 壓 柱 內 的 質量 傳 遞 不 會 損 害 局 純 度 氮 產 物 的純度 且 低 壓 柱 的 操 作壓 力 不 必 匹 配 冷 凍 供 應 系 統 的 壓 力要求 〇 (： 適. 合丨 的 冷 凍 流體 之 ·— 例 爲 仍 含有 高 揮 發 性 雜 質 的氮氣 i ) 〇 反 之 在 已 知製 程 的 冷 凍 供 應 系 統 中 ， 殘 餘 餾 份，例 如 來 白 頂 部 冷 凝 器的 蒸 發 空 間 者 係 被 抽取 出 ， 以 作功方 式 膨 脹 至 約 大 氣 壓力 及 由 製 程 被 移 出 0 在 此 案 例 中，僅 由 冷 -3 凍 供 應 系 統 來決定 頂 部 冷 凝 552391 五、發明說明（2) 器上和低壓柱的最小操作壓力。本發明中可避免此缺點， 而不會減少產物的純度。 本發明中，冷凍流體較佳爲送入低壓柱的頂部。 在本發明的第一變化例中，冷凍流體由壓力柱被移出， 以作功方式在冷凍供應系統內膨脹，及被導入低壓柱內。 流體的作功膨脹，尤其是氣體由壓力柱至低壓柱，係能特 別有利地產生製程的冷凍。在此方式中，絕緣與交換損失 可被補償，且若適當地話，少量的產物可被液化。在作功 膨脹的上游處，冷凍流體較佳爲以間接熱交換方式被加熱 (相對於被冷卻的製程束流）。 質量傳遞段是由一或多個精餾板（稱障礙板）所形成的， 爲此目的’給予”實際”板數的資訊，或是短塡充段（”理論 ”板數）。障礙板或理論板數，例如是1至10，較佳2至3 。由於氮產物是在這些障礙板下方被抽取出，故氮產物具 有非常低量的高揮發性雜質，此雜質殘留在低壓柱頂部中 ，且由該處與純度較低的氮氣流被抽取出。 、 冷凍流體一般都含有比氮氣更揮發的成分。然而，由於 進行發生在上述質量傳遞段上方，因此這些成分並沒有進 入更下方所抽取出的氮產物中。 若由壓力柱的上部區域移出冷凍流體，則係較有利的。 其例如是由來自壓力柱之富氮氣餾份，尤其是由此柱的頂 部氣體，所形成的。 依照本發明的第二個變化例，冷凍流體是由已經在精餾 552391 五、發明說明 (3: ) 系統 外 製 的低 溫 流 體所形成。 由 於 外 部 液體 係 當 作冷凍來源（液體輔助）被 送’ 入 1 所以 此方 法 具 有特別 局 的 彈性。舉例而言，用來產 生 冷 凍 作用 的機 械 例 如膨 脹 渦 輪，可完全或部分地被免 除 0 低 溫液 體， 例 如 可由 源 白 於另一個分餾空氣設備的 液 態 氮 所形 成； 或 者 可使 用 空 氣成分的其它混合物。外 部 液 體 可經 由管 路 供 應 或由 儲 槽 移出。其被送入對應於外 部 液 體 之組 成物 的 點 〇 此可 爲 壓 力柱或低壓柱的上部區域 〇 低 溫 液 體 可部 分地 或完全地被導入低壓柱內 較 佳 爲在 柱頂 〇 作 爲 替代 例 和 附加地，低溫液體可至少 部 分 被 導入 壓力柱的 上 部區 域 內 〇 頂 部 冷 凝 器的 冷 凍 劑較佳爲由低壓柱下部區 域 被 移 出， 且壓 力 的 所 有富 氧 產 物被送入低壓柱內。在本文中， "吉 田 氧”係意指具有氧含量大於空氣的餾份。 氮 產 物 可 從低 壓 柱 中以氣體狀被抽取出。另 可 選 擇 地， 其係 由 低 壓 柱中 以 液 體狀被抽取出，然後與已 經 作功 膨脹 的冷 凍 流 體 作間 接 熱 交換而蒸發。此二方法步 驟 之 組 合亦 可行 的 0 此外 ， 本 發明 關 於 一種如申請專利範圍第1C 丨至： 12 項之 裝置 0 .以 下 參 照 二個 例示 實施例（本發明兩個變化例各- -痼）來 更詳 細 說 明 本發 明 及本發明更進一步的細節。 在 第 1 圖 所例 示的 實施例中，壓縮和乾淨的 -5 - 空 氣 1 係在 552391 五、發明說明（4 ) 主熱交換器2中被冷卻及送（3)入壓力9至13巴的壓力柱 4。此精餾系統亦具有低壓柱5，其在2至5巴的壓力下操 作，且係經由共用的冷凝器-蒸發器（主冷凝器）6與壓力柱 成熱交換連通。已經由壓力柱頂部移出的氮氣部分.8係在 主冷凝器中6被液化，且經由管路9和1 0，部份地當作回 流被加到壓力柱中。來自主冷凝器6的液體9之另一束流 14係被過冷卻（15)，且此束流的第一部分20係當作回流 被送到低壓柱5頂部。過冷卻後的氮之第二部分2 1係當 作液體產物（PLIN)被移出。在過冷卻15後，來自壓力柱 的底部液體1 1係被節流（1 2 )而當作含氧液體餾份進入低 壓柱5內。 低壓柱5的底部液體13同樣地也被過冷卻（15)及膨脹 (1 6 )，然後被導入低壓柱5的頂部冷凝器1 7的蒸發空間 內。來自低壓柱5頂部的氣態氮1 8係在此冷凝器的液化 空間中被冷凝；冷凝液1 9被送回到低壓柱內，其中它被 用當作附加回流。沖洗液（PURGE)係連續地或間歇地經由 管路22由頂部冷凝器1 7的蒸發空間之下部區域抽取出。 頂部冷凝器17中所產生的蒸氣23係在熱交換器15和2 中被溫熱至約周圍溫度，及經由管路24被廢棄’及/或被 用當作淸潔裝置（例如，分子篩段，其未於圖示）的再生氣 體。未冷凝的氣體，特別是含有比較高揮發性的成分，係 經由管3 5被抽取出。其被吹掉（3 6 )及/或與蒸氣2 3混合 (37)。 ， 552391 五、發明說明（5) 在低壓柱5之頂部下方，有質量傳遞段25，其在此例中 係由三個實際板（障礙板）所形成。在此下方，氣態氮係當 作高純度產物經由管路26被移出且在熱交換器1 5和2中 被溫熱至約周圍溫度。在例示的實施例中，溫氮氣產物27 係在具有後冷卻器29的氮氣壓縮機28中被更進一步地壓 縮，且最後經由管路30當作最終產物（PGAN)被抽取出。 經由管路3 1，一部分的氣態頂部氮係由壓力柱4當作冷 凍流體被抽取出，其在主熱交換器2中被溫熱至中等溫度 ，然後經由管路32被送到膨脹機33，該膨脹機係被設計 發電機滑輪。已經以作功方式膨脹至約低壓柱壓力的冷凍 流體3 4係被送到低壓柱的頂部，即被送到障礙板2 5的上 方。依本發明的第一個變化例，這些方法步驟和/或它們 所用的裝置零件係用來形成冷凍供應系統。 作爲替代例或附加地，依照本發明的第一個變化例，當 作冷凍流體的氮可在”冷凍供應系統”中被壓縮至約壓力柱 的壓力以上，且然而可以作功方式膨脹，及被送入壓力柱 中（較佳爲在頂部）（未於圖示）。 若渦輪3 3故障時’則設備能以緊急模式操作，藉由來 自精餾系統外的低溫流體（3 8 )，其被送入冷凍系統的管柱 之一（“液體輔助”），如第2圖之實施例中所詳細說明。不 像近來的專利申請案’低溫流體未必需要在冷凍系統外製 造；而是設備之正常操作期間所產生的且儲存在儲槽內的 液（例如液態氮）係亦可用於緊急操作。 552391 五、發明說明（6) 第1圖中所示的例示實施例可被修改成：氣態及/或液 態氧產物係在低壓柱中被製造。爲此目的，來自壓力柱的 底部液體1 1只有一部分被節流，在過冷卻1 5後當作含氧 的液體餾份進入低壓柱5內；另一部分爲閥12之分歧的 上流，且通入頂部冷凝器1 7的蒸發空間內。完全或部分 地消除底部液體由低壓柱進給1 6至此蒸發空潤。氧產物 係以氣體狀及/或液體狀由低壓柱5的底部區域被抽取出 〇 在第2圖所例示的實施例中，壓縮和乾淨的空氣1係在 主熱交換器2中被冷卻及送（3)入壓力9至10巴的壓力柱 4。而且，此精餾系統亦具有低壓柱5，其在2至3巴的壓 力下操作，且係經由共用的冷凝器-蒸發器（主冷凝器）6與 壓力柱成熱交換連通。已經由壓力柱頂部移出的氮氣8係 在主冷凝器中6被液化，且經由管路9和1 0，部份地當作 回流被加到壓力柱中。來自主冷凝器6的液體9之另一部 分1 4係被過冷卻（1 5 )，且其之第一部分20係當作回流被 送到低壓柱5頂部。過冷卻後的氮之第二部分21係當作 液體產物PL IN被移出。在過冷卻15後，來自壓力柱的底 部液體11係被節流（12)而當作含氧液體餾份進入低壓柱5 內。 低壓柱5的底部液體1 3同樣地也被過冷卻（丨5 )及膨脹 (16)，然後被導入低壓柱5的頂部冷凝器17的蒸發空間 內。來自低壓柱5頂部的氣態氮1 8係在此冷凝器的液化552391 V. Description of the invention (1;) The present invention relates to a method for producing nitrogen gas by distilling air at a low temperature in a rectification system. The system has a pressure column and a low pressure column. In this method, the feed air is guided into the pressure column. The oxygen-containing liquid fraction is removed from the pressure column and then sent into the low-pressure column. 0 Gaseous nitrogen is extracted from the low-pressure column above the mass transfer section. It has at least one R3A or actual plate. The top condenser is at least partially condensed by indirect heat exchange with the refrigerant. The local purity nitrogen is removed from the low pressure column below the mass transfer section and is obtained as a nitrogen product. The present invention is of the type described in the introduction. The method and the corresponding economically particularly advantageous device are regarded as giant 0 based on the fact that this giant is achieved by the following facts • The method has a refrigeration supply system 1 in which a refrigerant fluid is flowing and a refrigerant fluid from a refrigeration supply system Is introduced into the low pressure column above the mass transfer section as an alternative or in addition in the context of the present invention The refrigerated fluid can also be introduced into the upper region of the pressure column. In the present invention, an easily available medium can be used to form the refrigerated fluid introduced into the low pressure column. This process involves mass transfer in the low pressure column without compromising local purity nitrogen The purity of the product and the operating pressure of the low-pressure column do not have to match the pressure requirements of the refrigeration supply system. (: Suitable refrigerating fluids. Example: nitrogen that still contains high volatile impurities i). Conversely, refrigeration in known processes In the supply system, the residual distillate, such as the evaporation space from the white top condenser, is extracted, expanded to about atmospheric pressure by work and removed by the process. In this case, only cold -3 frozen supply System to determine the top condensation 552391 V. Description of the invention (2) Minimum operating pressure on the vessel and low pressure column. This disadvantage can be avoided in the present invention without reducing the purity of the product. In the present invention, the refrigerated fluid is preferably sent to the top of the low pressure column. In a first variation of the present invention, the refrigerating fluid is removed from the pressure column, expands in the refrigeration supply system in a work manner, and is introduced into the low-pressure column. The work expansion of a fluid, especially the passage of gas from a pressure column to a low pressure column, is particularly advantageous for producing process freezing. In this way, insulation and exchange losses can be compensated and, if appropriate, a small amount of product can be liquefied. Upstream of the work expansion, the refrigerated fluid is preferably heated in an indirect heat exchange manner (relative to the cooled process beam). The mass transfer section is formed by one or more rectifying plates (called obstacle plates), for this purpose, 'information' is given to the number of "actual" plates, or short filling sections ("theoretical" plates). The number of obstacle boards or theoretical boards is, for example, 1 to 10, and preferably 2 to 3. Because the nitrogen product is extracted under these barriers, the nitrogen product has a very low amount of highly volatile impurities that remain in the top of the low-pressure column and are extracted by a lower-purity nitrogen stream there. Frozen fluids generally contain more volatile components than nitrogen. However, because the process takes place above the mass transfer section, these components do not enter the nitrogen product extracted further below. It is advantageous if the refrigerated fluid is removed from the upper region of the pressure column. It is formed, for example, from a nitrogen-rich fraction from a pressure column, especially from the top gas of the column. According to a second variation of the present invention, the refrigerated fluid is formed by a low temperature fluid that has been produced outside the rectification 552391 V. Description of the Invention (3 :) system. Since the external liquid is sent as a source of freezing (liquid assisted), it is fed into 1 so this method is particularly flexible. For example, machinery used to generate refrigeration, such as expansion turbines, can be completely or partially exempted from 0 cryogenic liquids, such as formed from liquid nitrogen originating from another fractionated air plant; or other mixtures of air components can be used . The external liquid can be supplied by the pipeline or removed from the storage tank. It is fed into the point corresponding to the composition of the external liquid. This may be the upper area of the pressure column or the low pressure column. The cryogenic liquid may be partially or completely introduced into the low pressure column, preferably at the top of the column. As an alternative and Additionally, the cryogenic liquid may be at least partially introduced into the upper region of the pressure column. The refrigerant in the top condenser is preferably removed from the lower region of the low pressure column, and all the oxygen-rich products at pressure are sent into the low pressure column. In this context, " Yoshida oxygen " means a fraction having an oxygen content greater than that of air. The nitrogen product can be extracted as a gas from a low pressure column. Alternatively, it can be extracted as a liquid from a low pressure column. It is extracted and then indirect heat exchanged with the refrigerated fluid that has undergone work expansion to evaporate. The combination of these two method steps is also feasible. In addition, the present invention relates to a device such as the scope of patent application No. 1C to: 12 items 0. Hereinafter, the present invention and further details of the present invention will be described in more detail with reference to two exemplary embodiments (each of two variations of the present invention-痼). In the embodiment illustrated in Fig. 1, the compressed and clean -5 -Air 1 is in 552391 V. Description of the invention (4) The main heat exchanger 2 is cooled and sent (3) into a pressure column 4 with a pressure of 9 to 13 bar. This rectification system also has a low pressure column 5, which is at 2 Operates at pressures up to 5 bar and is in heat exchange communication with the pressure column via a common condenser-evaporator (main condenser) 6. The portion of nitrogen removed from the top of the force column. 8 is liquefied in the main condenser 6 and is partially added to the pressure column as reflux via lines 9 and 10. The liquid 9 from the main condenser 6 The other beam 14 is supercooled (15), and the first part 20 of this beam is sent back to the top of the low pressure column 5. The second part 21 of the supercooled nitrogen is treated as a liquid product ( PLIN) is removed. After subcooling 15, the bottom liquid 11 from the pressure column is throttled (12) and enters the low pressure column 5 as an oxygen-containing liquid fraction. The bottom liquid 13 of the low pressure column 5 is the same It is also supercooled (15) and expanded (16), and then introduced into the evaporation space of the condenser 17 at the top of the low pressure column 5. Gaseous nitrogen 18 from the top of the low pressure column 5 is in the liquefaction space of this condenser Is condensed; the condensate 19 is returned to the low-pressure column, where it is used as an additional reflux. The flushing liquid (PURGE) is continuously or intermittently under the evaporation space of the top condenser 17 through the line 22 The area 23 is extracted. The vapor 23 generated in the top condenser 17 is warmed in the heat exchangers 15 and 2 to about Ambient temperature, and is discarded via line 24 'and / or used as a regeneration gas for cleaning equipment (eg, molecular sieve section, which is not shown). Non-condensing gases, especially those containing relatively high volatility The component is extracted through the tube 35. It is blown off (3 6) and / or mixed with the vapor 2 3 (37). 552391 V. Description of the invention (5) There is mass under the top of the low pressure column 5. The transfer section 25, which in this example is formed by three actual plates (obstacle plates). Below this, gaseous nitrogen is removed as a high-purity product via line 26 and is warmed to about ambient temperature in heat exchangers 15 and 2. In the illustrated embodiment, the warm nitrogen product 27 is further compressed in a nitrogen compressor 28 having an aftercooler 29, and is finally extracted as a final product (PGAN) via line 30. Via line 31, a part of the gaseous top nitrogen system is extracted by the pressure column 4 as a refrigeration fluid, which is warmed to a medium temperature in the main heat exchanger 2 and then sent to the expander 33 through the line 32 The expander is designed as a generator pulley. The chilled fluid 3 4 which has been expanded by work to about the pressure of the low pressure column is sent to the top of the low pressure column, that is, to the top of the obstacle plate 25. According to a first variant of the invention, these method steps and / or the parts of the equipment they are used to form a refrigeration supply system. As an alternative or in addition, according to a first variation of the present invention, nitrogen as a refrigerated fluid may be compressed in a "frozen supply system" to above the pressure of a pressure column, but may be expanded in a work manner, and Into the pressure column (preferably at the top) (not shown). If the turbine 33 fails, then the equipment can be operated in emergency mode, with the cryogenic fluid (38) from outside the rectification system being sent to one of the tubing columns of the refrigeration system ("liquid assist"), as in section This is illustrated in detail in the embodiment of FIG. 2. Unlike the recent patent application, 'Cryogenic fluids do not necessarily need to be manufactured outside the refrigeration system; instead, liquids (such as liquid nitrogen) generated during normal operation of the equipment and stored in storage tanks can also be used for emergency operations. 552391 V. Description of the invention (6) The exemplified embodiment shown in Fig. 1 may be modified so that gaseous and / or liquid oxygen products are manufactured in a low pressure column. For this purpose, only a part of the liquid 11 from the bottom of the pressure column is throttled, and after being cooled 15, it is treated as an oxygen-containing liquid fraction and enters the low-pressure column 5; the other part is the divergent upstream of the valve 12, and the Into the evaporation space of the top condenser 17. Completely or partially eliminate the bottom liquid from the low-pressure column feed 16 until the evaporation and moistening. The oxygen product is extracted from the bottom region of the low pressure column 5 in a gaseous and / or liquid state. In the embodiment illustrated in FIG. 2, the compressed and clean air 1 is cooled in the main heat exchanger 2 and Feed (3) into pressure column 4 with a pressure of 9 to 10 bar. Furthermore, this rectification system also has a low pressure column 5 which operates at a pressure of 2 to 3 bar and is in heat exchange communication with the pressure column via a common condenser-evaporator (main condenser) 6. The nitrogen 8 that has been removed from the top of the pressure column is liquefied in the main condenser 6 and is partially added to the pressure column as reflux through lines 9 and 10. The other part 14 of the liquid 9 from the main condenser 6 is subcooled (15), and the first part 20 is sent to the top of the low pressure column 5 as reflux. The second part 21 of the supercooled nitrogen is removed as a liquid product PL IN. After subcooling 15, the bottom liquid 11 from the pressure column is throttled (12) and enters the low pressure column 5 as an oxygen-containing liquid fraction. The liquid 13 at the bottom of the low-pressure column 5 is also supercooled (5) and expanded (16), and then introduced into the evaporation space of the condenser 17 at the top of the low-pressure column 5. Gaseous nitrogen 18 from the top of the low pressure column 5 is liquefied in this condenser
552391 五、發明說明（7) 空間中被冷凝；冷凝液1 9被送回到低壓柱內，其中它被 用當作附加回流。沖洗液（PURGE)係連續地或間歇地經由 管路22由頂部冷凝器1 7的蒸發空間之下部區域抽取出。 頂部冷凝器17中所產生的蒸氣23係在熱交換器15和2 中被溫熱至約周圍溫度，及經由管路24被廢棄，及/或被 用當作淸潔裝置（例如，分子篩段，其未於圖示）的再生氣 體。未冷凝的氣體，特別是含有比較高揮發性的成分，係 經由管路35被抽取出。其被吹掉（36)及/或與蒸氣23混 合（37)。 在低壓柱5之頂部下方，有質量傳遞段25，其在此例中 係由三個實際板（障礙板）所形成。在此下方，氣態氮係當 作高純度產物經由管路26被移出且在熱交換器1 5和2中 被溫熱至約周圍溫度。在例示的實施例中，溫氮氣產物2 7 係在具有後冷卻器29的氮氣壓縮機28中被更進一步地壓 縮’且最後經由管路30當作最終產物（PGAN)被抽取出。 精I留系統裡中管柱4，5之一所尙未製造的液態氮係經由 管路38送入低壓柱的頂部，即障礙板25上方。在此例中 ’低溫流體係由儲槽3 9被移出，該儲槽經外部來源所塡 充，例如經桶槽。依照本發明的第二個變化例，這些方法 步驟及/或用於攜帶它驟出來的裝置零件係形成一種”冷凍 供應系統”。 作爲替代例或附加地，在依照本發明的第二個變化例之 ”冷凍供應系統，，中，來自儲槽39的液態氮可當作冷凍流 552391 五、發明說明（8) 體被送入壓力柱內（較佳在頂部）（未於圖示）。 第2圖中所示的例示實施例可被修改成：氣態及/或液 態氧產物係在低壓柱中被製造。爲此目的，來自壓力柱的 底部液體1 1只有一部分被節流，在過冷卻1 5後當作含氧 的液體餾份進入低壓柱5內；另一部分爲閥1 2之分歧的 上流，且通入頂部冷凝器1 7的蒸發空間內。完全或部分 地消除底部液體由低壓柱進給1 6至此蒸發空間。氧產物 係以氣體狀及/或液體狀由低壓柱5的底部區域被抽取出。 圖式簡蚩說明 第1圖係本發明之第一變化例的實施例。 第2圖係本發明之第二變化的的實施例。 元件符號說明 1 壓縮和乾淨的空氣 2 主熱交換器 3 送 4 壓力柱 5 低壓柱 6 主冷凝器 8 氮氣 9,10 管路 11 底部液體 12 節流 13 底部液體 14 束流 -10- 552391 發明說明（9) 15 過冷卻 16 膨脹 17 頂部冷凝器 18 氣態氮 19 冷凝液 20 第一部分 21 第二部分 22 管路 23 蒸氣 24 管路 25 質量傳遞段 26 管路 27 溫氮氣產物 28 氮氣壓縮機 29 後冷卻器 30,31,32 管路 33 膨脹機 34 冷凍流體 35 管路 36 吹掉 37 混合 38 管路 39 儲槽 -11-552391 V. Description of the invention (7) The space is condensed; the condensate 19 is returned to the low-pressure column, where it is used as additional reflux. The flushing liquid (PURGE) is continuously or intermittently drawn from the lower area of the evaporation space of the top condenser 17 through the line 22. The vapor 23 generated in the top condenser 17 is warmed to about ambient temperature in the heat exchangers 15 and 2 and is discarded via the line 24 and / or used as a cleaning device (for example, a molecular sieve section) , Which is not shown in the figure). The uncondensed gas, especially the relatively highly volatile components, is extracted through the pipe 35. It is blown off (36) and / or mixed with steam 23 (37). Below the top of the low-pressure column 5, there is a mass transfer section 25, which in this example is formed by three actual plates (barrier plates). Below this, gaseous nitrogen is removed as a high-purity product via line 26 and is warmed to about ambient temperature in heat exchangers 15 and 2. In the illustrated embodiment, the warm nitrogen product 27 is further compressed 'in a nitrogen compressor 28 having an aftercooler 29 and is finally extracted as a final product (PGAN) via line 30. The unmanufactured liquid nitrogen in one of the tubing columns 4, 5 in the fine I retention system is sent to the top of the low-pressure column through the pipe 38, that is, above the obstacle plate 25. In this example, the 'low temperature flow system is removed from a storage tank 39, which is filled by an external source, such as a barrel tank. According to a second variant of the invention, the method steps and / or the device parts used to carry it out form a "freezing supply system". As an alternative or in addition, in the "frozen supply system" according to the second modification of the present invention, the liquid nitrogen from the storage tank 39 can be used as the frozen stream 552391. 5. Description of the invention (8) Inside the pressure column (preferably at the top) (not shown). The exemplary embodiment shown in Figure 2 can be modified so that gaseous and / or liquid oxygen products are manufactured in a low pressure column. To this end, Only a part of the liquid 11 from the bottom of the pressure column is throttled. After subcooling 15, it is treated as an oxygen-containing liquid fraction and enters the low-pressure column 5. The other part is the divergent upflow of the valve 12 and flows into the top to condense. In the evaporation space of the device 17, the bottom liquid is completely or partially eliminated from the low pressure column feed 16 to this evaporation space. The oxygen products are extracted in the form of gas and / or liquid from the bottom area of the low pressure column 5. Schematic Brief description of the first diagram is an embodiment of the first modified example of the present invention. The second diagram is an embodiment of the second modified example of the present invention. Element symbol description 1 compressed and clean air 2 main heat exchanger 3 send 4 Pressure column 5 Low pressure column 6 Main condenser 8 Nitrogen 9, 10 Pipeline 11 Bottom liquid 12 Throttle 13 Bottom liquid 14 Beam -10- 552391 Description of the invention (9) 15 Subcooling 16 Expansion 17 Top condenser 18 Gaseous nitrogen 19 Condensate 20 First part 21 Second part 22 Line 23 Steam 24 Line 25 Mass transfer section 26 Line 27 Warm nitrogen products 28 Nitrogen compressor 29 After cooler 30, 31, 32 Line 33 Expander 34 Refrigerant fluid 35 Line 36 Blow off 37 Mix 38 Line 39 Tank-11-