JPS5895181A - Pre-treatment method for air separator - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 本発明は空気から純酸素、純窒素などを得るための空気
分離装置に係り、特に空気分離装置の精留塔に流入又は
流出する空気又はガスの流量及び圧力の変動を抑制し、
且つ空気中の水分及び炭酸ガスを効率的に除去する空気
分離装置の前処理方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air separation device for obtaining pure oxygen, pure nitrogen, etc. from air, and particularly to fluctuations in the flow rate and pressure of air or gas flowing into or out of a rectification column of the air separation device. suppress,
The present invention also relates to a pretreatment method for an air separation device that efficiently removes moisture and carbon dioxide from the air.

空気から純酸素、純窒素などを回収する空気分離装置は
低温下で運転さｈるために空気中に存在する水分、炭酸
ガスが凝縮固化し、装置の運転を阻害する。空気は膨張
による低温源を得るため圧縮機で加圧後空気分離装置に
供給される。従って空気中には圧縮機後部冷却器出口に
おける圧力及び温度での飽和湿度相当の水分及び３００
ないし４００　ｐｐｍ　　の炭酸ガスが含まれるので、
これらの除去を必要とする。従来、水分及び炭酸ガスの
除去法として、精留塔に供給される空気と精留塔から排
出される純酸素、純窒素及び廃窒素を熱交換する可逆熱
交換器を利用する方法（以下可逆熱交法と称する）、又
は温度差吸着方式（ＴｈｅｒｍａｌＳｗｉ、ｎｇ　Ａｄ
ｓｏｒｐｔｉｏｎ　）を採用した前処理装置を使用する
方法（以下、ＴＳＡ法と称する）が採用されてきた。前
者は、空気流路と廃窒素流路を交互に切換えることがで
きる可逆熱交換器を使用するもので、まず、熱交換器配
管内に空気中の水分及び炭酸ガスを固化析出させて除去
し、次に空気流量と廃窒素流路を切換えて廃窒素により
水分及び炭酸ガスを気化させて熱交換器から系外に排出
し、これらの操作を交互に行わせることによって連続的
に水分及び炭酸ガスを除去した空気を精留塔に供給する
ものである。しかし、本方法では固化析出した水分及び
−炭酸ガスを気化させる際に空気流量の約７０％の廃窒
素を必要とするために純酸素及び純窒素からなる製品の
空気に対する回収率が低くなること、空気と廃窒素の流
路切換え時に流量及び圧力の変動が大きいことなどの問
題点があった。Since air separation equipment that recovers pure oxygen, pure nitrogen, etc. from air is operated at low temperatures, moisture and carbon dioxide gas present in the air condense and solidify, impeding the operation of the equipment. Air is compressed by a compressor to obtain a cold source by expansion and then supplied to an air separation device. Therefore, the air contains moisture equivalent to the saturated humidity at the pressure and temperature at the outlet of the cooler at the rear of the compressor, and 300%
It contains between 400 ppm and 400 ppm of carbon dioxide gas,
These require removal. Conventionally, as a method for removing moisture and carbon dioxide gas, a method using a reversible heat exchanger (hereinafter referred to as reversible heat exchange method) or temperature difference adsorption method (ThermalSwi, ng Ad
A method (hereinafter referred to as the TSA method) using a pre-treatment device employing the TSA method (Sorption) has been adopted. The former uses a reversible heat exchanger that can alternately switch between the air flow path and the waste nitrogen flow path. First, moisture and carbon dioxide in the air are solidified and precipitated in the heat exchanger piping and removed. Next, the air flow rate and the waste nitrogen flow path are switched to vaporize moisture and carbon dioxide using the waste nitrogen and discharge it from the heat exchanger to the outside of the system. By performing these operations alternately, moisture and carbon dioxide are continuously removed. Air from which gas has been removed is supplied to the rectification column. However, this method requires approximately 70% of the air flow rate of waste nitrogen to vaporize the solidified and precipitated moisture and carbon dioxide gas, resulting in a low recovery rate of products consisting of pure oxygen and pure nitrogen relative to air. However, there were problems such as large fluctuations in flow rate and pressure when switching between air and waste nitrogen flow paths.

後者は、低温吸着−高温脱着という温度差吸着方法を採
用した複数の吸着塔からなる前処理装置を使用するもの
で、まず吸着塔内の吸着剤と空気を５ないし２０Ｃの温
度で接触させて水分及び炭酸ガスを吸着除去し、次に２
００ないし３００Ｃに加熱した碩窒素を吸着剤に接触さ
せて水分及び炭酸ガスを脱着して吸着剤を再生し、これ
らの操作を複数の吸着塔を用いて交互に行わせることに
よって連続的に水分及び炭酸ガスを除去した空気を精留
塔に供給するものである。本方法では吸着剤の再生に使
用する廃窒素流量は特公昭４７−３５１８５号公報等に
□例示されているように空気流量の１０ないし４０チに
低減できるため可逆熱交法に比べて製品の回収率を向上
させることができる。しかし、吸着剤の再生を高温下で
行わせるため多大な熱量を必要とし、製品の電力原単位
が上昇して製造コストを増加させる。また、吸着剤の急
激な加熱−冷却が困難であるため吸着塔の切換え時間が
長くなり、吸着剤量の増加、装置の大型化などの問題点
があった。The latter uses a pretreatment device consisting of multiple adsorption towers that employs a temperature difference adsorption method called low-temperature adsorption and high-temperature desorption.First, the adsorbent in the adsorption tower is brought into contact with air at a temperature of 5 to 20C. Water and carbon dioxide are adsorbed and removed, then 2
The adsorbent is regenerated by bringing nitrogen heated to 00 to 300C into contact with the adsorbent to desorb moisture and carbon dioxide, and these operations are performed alternately using multiple adsorption towers to continuously remove moisture. and air from which carbon dioxide gas has been removed is supplied to the rectification column. In this method, the waste nitrogen flow rate used for regenerating the adsorbent can be reduced to 10 to 40 inches of the air flow rate, as exemplified in Japanese Patent Publication No. 47-35185, etc., so the product quality is lower than that of the reversible heat exchange method. Recovery rate can be improved. However, since regeneration of the adsorbent is performed at high temperatures, a large amount of heat is required, which increases the power consumption of the product and increases manufacturing costs. Furthermore, since it is difficult to rapidly heat and cool the adsorbent, there are problems such as a long switching time between adsorption towers, an increase in the amount of adsorbent, and an increase in the size of the apparatus.

以上の観点から、廃窒素使用量及び熱使用量が少なく、
且つ流量及び圧力変動が少ない新たな水分及び炭酸カス
の除去法が要望され、この要望に対処するために圧力差
吸着方式−（ＰｒｅｓｓｕｒｅＳｗｉｎｇ　Ａｄｓｏｒ
ｐｔｉｏｎ　　）　　を採用した前処理装置を使用する
方法（以下ＰＳＡ法と称する）が提案されている。本方
法は高圧吸着−低圧脱着という圧力差吸着方式を採用し
た複数の吸着塔からなる前処理装置を使用するもので、
まず低温源を得る目的で加圧された空気を常温（５ない
し４０Ｃ）下で吸着剤と接触させ水分及び炭酸ガスを吸
着除去し、次に上記空気との熱交換により上記空気温度
と同等もしくはそれ以下の温度及び大気圧前後の圧力の
状態の廃窒素ガスを吸着剤に接触させて水分及び炭酸ガ
スを脱着して吸着剤を再生し、これらの操作を複数のｉ
Ｊ塔を用いて交互に行わせることによって連続的に水分
及び炭酸ガスを除去した空気を精留塔に供給するもので
ある。本方法では吸着剤の再生に使用する廃窒素流量を
空気流量の３０ないし４０％に低減できるため可逆熱交
法に比べて製品の回収率を向上することができる。また
、吸着剤の再生を行う際に加熱源を必要としないために
ＴＥＡ法に比べて省エネルギ化が図られ、製造コストの
低減が可能となった。更に、吸着剤の加熱−冷却が不要
なため吸着塔の切換え時間を短縮でき、装置の小型化が
達成されるという効果がある。このよ・うに、ＰＳＡ法
による前処理装置は多くの特長を有するが、本装置を適
用した空気分離装置を運転する際に空気中の水分及び炭
酸ガスを効率的に除去し、且つ製品である純酸素及び純
窒素の純度を高くするためには、吸着塔切換え時の空気
の収支あるいは時間配分が大きく影響し、その最適化な
しにはＰＳＡ法適用の効果が達成されないばかりでなく
、空気分離装置の運転阻害に・もなりかねないことが判
明した。From the above points of view, the amount of waste nitrogen and heat used is small.
In addition, there is a demand for a new method for removing moisture and carbon dioxide with less fluctuation in flow rate and pressure.
A method (hereinafter referred to as the PSA method) using a preprocessing device employing the PSA method has been proposed. This method uses a pretreatment device consisting of multiple adsorption towers that employs a pressure difference adsorption method called high-pressure adsorption and low-pressure desorption.
First, in order to obtain a low-temperature source, pressurized air is brought into contact with an adsorbent at room temperature (5 to 40C) to adsorb and remove moisture and carbon dioxide, and then heat exchanged with the above air to achieve a temperature equal to or equal to the above air temperature. Waste nitrogen gas at a temperature below this temperature and a pressure around atmospheric pressure is brought into contact with an adsorbent to desorb moisture and carbon dioxide gas and regenerate the adsorbent, and these operations are repeated multiple times.
Air from which moisture and carbon dioxide have been continuously removed by alternately using J towers is supplied to the rectification tower. In this method, the waste nitrogen flow rate used for regenerating the adsorbent can be reduced to 30 to 40% of the air flow rate, so the product recovery rate can be improved compared to the reversible heat exchange method. Furthermore, since no heating source is required when regenerating the adsorbent, energy savings can be achieved compared to the TEA method, and manufacturing costs can be reduced. Furthermore, since there is no need to heat and cool the adsorbent, the adsorption tower switching time can be shortened, and the apparatus can be made more compact. As described above, the pretreatment device using the PSA method has many features, but when operating an air separation device to which this device is applied, it can efficiently remove moisture and carbon dioxide from the air, and it can also be used as a product. In order to increase the purity of pure oxygen and pure nitrogen, the air balance or time allocation when switching adsorption towers has a large influence, and without optimization, not only will the effects of applying the PSA method not be achieved, but also the air separation It has been found that this may impede the operation of the equipment.

本発明の目的は、空気分離装置で製造される純酸素及び
純窒素の純度を低下させることなく、空気中の水分及び
炭酸ガスを効率的に除去する圧力差吸着方法に゛よる空
気分離装置の前処理方法を提供することにある。The object of the present invention is to develop an air separation device using a pressure difference adsorption method that efficiently removes moisture and carbon dioxide from the air without reducing the purity of pure oxygen and pure nitrogen produced in the air separation device. An object of the present invention is to provide a pretreatment method.

即ち本発明の特徴は、一方の塔において吸着圧力下で加
圧空気を流通させて吸着剤によって水分及び炭酸ガスを
除去する吸着工程を行わせ、他の塔において吸着圧力か
ら脱着圧力まで降圧させる減圧工程、ｌ圧力下で廃窒素
を流通させて吸着剤を再生するパージ工程及び脱着圧力
から吸着圧力まで昇圧させる加圧工程を順に行わせ、こ
れらを交互に行わせることにより連続的に精製された加
圧空気を得る空気分離装置の前処理法において、一方の
塔の加圧工程時、他の塔の吸着圧力を設定された吸着圧
力の０．７５以上に保持し、同時に加圧時間とサイクル
時間の比が０．２以下になるように加圧速度を調整する
ことを特徴とする空気分離装置の前処理方法にある。That is, the feature of the present invention is that an adsorption process is performed in which pressurized air is passed under adsorption pressure in one column to remove moisture and carbon dioxide by an adsorbent, and the pressure is lowered from adsorption pressure to desorption pressure in the other column. The depressurization process, the purge process in which waste nitrogen is circulated under 1 pressure to regenerate the adsorbent, and the pressurization process in which the pressure is increased from the desorption pressure to the adsorption pressure are performed in sequence, and these steps are performed alternately to achieve continuous purification. In a pretreatment method for an air separation device to obtain pressurized air, during the pressurization process of one column, the adsorption pressure of the other column is maintained at 0.75 or more of the set adsorption pressure, and at the same time the pressure is A pretreatment method for an air separation device is characterized in that the pressurization rate is adjusted so that the cycle time ratio is 0.2 or less.

第１図に２基の吸着塔（塔２１及び塔２２）を用いた場
合の本発明の運転サイクルを示す。図中θＴはサイクル
時間、θ−は予備吸着時間、θｂは減圧時間、θｄはパ
ージ時間、θ、は加圧時間を示す。予備吸着工程は加圧
工程から吸着工程に移る間に他塔の吸着工程と併行して
２基の塔で吸着工程を実施させるもので、θ−はその時
間を表わす。これらの時間の間には（１）及び（２）式
の関係が成立する。FIG. 1 shows the operating cycle of the present invention when two adsorption towers (tower 21 and tower 22) are used. In the figure, θT is the cycle time, θ- is the preliminary adsorption time, θb is the depressurization time, θd is the purge time, and θ is the pressurization time. In the preliminary adsorption step, an adsorption step is carried out in two towers in parallel with the adsorption step in another tower during the transition from the pressurization step to the adsorption step, and θ- represents the time. The relationships expressed by equations (1) and (2) hold between these times.

θ↑＝θ１＋θ；＋θｂ十θｄ十θＦ　−（１）θ、＝
θ；＋θ、＋θｄ＋θ、　−（２）第２図にサイクル時
間θ丁と炭酸ガス除去性能の関係を示す。（なお、水分
は炭酸ガスに比べて容易に除去され、炭酸ガス除去性能
を満足すれば水分も除去されるため記載を省略した。）
図において加圧時間θ、及び減圧時間θｂは共に１　ｍ
ｉｎである。図より炭酸ガス濃度は０丁が２０ないし４
０°分の範囲で最小となり、θＴが１０分以下又は６０
分以上では急激に上昇することがわかった。θ↑=θ1+θ;+θb+θd+θF −(1)θ,=
θ; +θ, +θd+θ, -(2) Figure 2 shows the relationship between cycle time θ and carbon dioxide removal performance. (Moisture is removed more easily than carbon dioxide, and if the carbon dioxide removal performance is satisfied, moisture is also removed, so the description is omitted.)
In the figure, the pressurization time θ and the depressurization time θb are both 1 m.
It is in. From the figure, the carbon dioxide concentration is 0 to 20 to 4.
It is minimum in the range of 0° min, and θT is 10 min or less or 60 min.
It was found that the temperature rises rapidly for more than 1 minute.

従ってＰＥＡ法前法理処理装置イクル時間は１０ないし
６０分の範囲、好ましくは２ｏないし４０分の範囲であ
る。Accordingly, the cycle time of the PEA preprocessing apparatus is in the range of 10 to 60 minutes, preferably in the range of 20 to 40 minutes.

次に、運転サイクル内の時間配分は水分及び炭酸ガス除
去性能だけでなく精留塔の酸素及び窒素の分離性能の両
者に影響を及はす。特に加圧時間の影響が大きく、加圧
時間゛を決定する加圧工程のガス流入速度すなわち加圧
速度の調整が重要であることを見出した。第３図に加圧
速度Ｑｐと・加圧時間とサイクル時間の比θｐ／θＴ及
び加圧工程時における吸着塔出口空気圧力の変化Ｐ／ｐ
ｏ　の関係を示す。ここで、加圧時間θ、は２基の吸着
塔の圧力が等しくなる。すなわち均圧に要した時間、圧
力Ｐは吸着塔出口空気圧力の最低値、圧力ｐ。Next, the time distribution within the operating cycle affects not only the moisture and carbon dioxide removal performance but also the oxygen and nitrogen separation performance of the rectification column. It has been found that the influence of the pressurization time is particularly large, and that it is important to adjust the gas inflow rate in the pressurization process, which determines the pressurization time, that is, the pressurization speed. Figure 3 shows the pressurization rate Qp, the ratio of pressurization time to cycle time θp/θT, and the change in adsorption tower outlet air pressure P/p during the pressurization process.
o shows the relationship. Here, during the pressurization time θ, the pressures of the two adsorption towers become equal. That is, the time required for pressure equalization and the pressure P are the minimum value of the air pressure at the outlet of the adsorption tower, the pressure p.

は吸着圧力を表わす。図から加圧速度Ｑ、の上昇によシ
均圧に要する時間が減少するだめθｐ／θＴは小さくな
るが、均圧に要するガス流量が増加するため、Ｐ／　ｐ
　ｏは減少する。第４図にθｐ／ｅ７と炭酸ガス除去性
能の関係を示す。炭酸ガス濃度Ｃ／Ｃ０はθ、／θ丁が
０．１５程度から上昇し始め、ｏ、２以上で急激に上昇
する。これは、加圧時間θ、の増加がパージ時間θｄの
減少につながるため、θ、／θＴの増加によって吸着剤
の再生効率が（ｆ下するためである。第５図に圧力変化
Ｐ／Ｐ　ｏと製品として回収される純窒素中の不純酸素
濃度の関係を示す。represents adsorption pressure. From the figure, as the pressurization speed Q increases, the time required for pressure equalization decreases, so θp/θT becomes smaller, but the gas flow rate required for pressure equalization increases, so P/p
o decreases. FIG. 4 shows the relationship between θp/e7 and carbon dioxide removal performance. The carbon dioxide concentration C/C0 begins to rise when θ, /θ d is about 0.15, and increases rapidly when θ, /θ d is about 0.15. This is because an increase in the pressurization time θ leads to a decrease in the purge time θd, and an increase in θ, /θT reduces the adsorbent regeneration efficiency (f). Figure 5 shows the pressure change P/P. The relationship between o and impure oxygen concentration in pure nitrogen recovered as a product is shown.

酸素濃度はＰ／Ｐｏが０．８５前後で変曲点をもち、０
．８５以下で急激に上昇した。またＰ　／Ｐｏ　カ０．
７５以下では精留塔内の液面変動、温度変化などが大き
く不安定現象を呈し、運転が困難となることが明らかに
なった。以上の結果から、炭酸ガスを効率的に除去し、
同時に高純度窒素を得るためには、θ、／θＴが０．２
以下でＰ／Ｐｏが０．７５以上になるように、゛好まし
くはθｐ／θＴが０．１５以下でＰ／Ｐ。The oxygen concentration has an inflection point when P/Po is around 0.85, and 0.
．． It rose sharply below 85. Also, P/Po is 0.
It has become clear that when the temperature is below 75, liquid level fluctuations and temperature changes within the rectification column become unstable, making operation difficult. From the above results, carbon dioxide gas can be efficiently removed,
In order to obtain high purity nitrogen at the same time, θ, /θT must be 0.2
In the following, P/P is preferably θp/θT of 0.15 or less so that P/Po is 0.75 or more.

が０．８５以上になるように加圧速度を調整しなければ
ならないことがわかった。It was found that the pressurization speed had to be adjusted so that the value was 0.85 or more.

上述したθ、／θ丁及びＰ／Ｐｏの値を満足するように
加圧速度を調整するために以下の方法が用いられる。The following method is used to adjust the pressurization rate so as to satisfy the above-mentioned values of θ, /θd and P/Po.

第１の方法として、加圧工程において、吸着工程を実施
している他塔の吸着塔出口空気圧力Ｐを検知し、該検知
値に応じて調節計により加圧工程時空気導入弁の開度を
調整し、Ｐ／Ｐｏ　　が０．７５以上になるように加圧
速度を制御する。この際、吸着塔の加圧による空気吸着
容量、精留塔のガス及び液の保有量などを考慮したうえ
でθ、／θＴが０．２以下になるように圧縮機容、量を
決定する。The first method is to detect the air pressure P at the outlet of the adsorption tower of another tower performing the adsorption process in the pressurization process, and use a controller to determine the opening of the air inlet valve during the pressurization process according to the detected value. and control the pressurization speed so that P/Po is 0.75 or more. At this time, the compressor capacity and amount are determined so that θ, /θT is 0.2 or less, taking into consideration the air adsorption capacity due to pressurization of the adsorption tower, the amount of gas and liquid held in the rectification tower, etc. .

第２の方法として、加圧工程時空気入ロ配管にオリフィ
スなどの絞り機構を設け、加圧工程時の空気導入量の最
大値を上記のＰ／Ｐｏの値が０．７５以上になるように
制限する。この際θＰ／θＴが０．２以下になるように
圧縮機容量を決定する。As a second method, a restriction mechanism such as an orifice is installed in the air intake piping during the pressurization process, and the maximum amount of air introduced during the pressurization process is set so that the above value of P/Po is 0.75 or more. limited to. At this time, the compressor capacity is determined so that θP/θT is 0.2 or less.

以上、２塔式を中心に述べたが、本発明は３塔以上の多
塔式に適用できることはいうまでもない。Although the above description has focused on a two-column type, it goes without saying that the present invention can be applied to a multi-column type with three or more towers.

以下、図に示す実施例を用いて本発明の詳細な説明する
。Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

実施例１ 第６図は本発明に係る空気分離装置の一実施例を示す系
統図である。第６図において、空気分離装置は圧縮機１
、冷却器２、ＰＳＡ法前法理処理装置３冷分離装置４な
どから構成される。配管５から導入された空気は圧縮機
１で加圧され、冷却器２、配管６を経由して前処理装置
３に送られ、固化成分である水分及び炭酸ガスを除去し
た後配管７を経由して深冷分離装置４に供給される。深
冷分離装置４は熱交換器、膨張タービン、精留塔などか
ら構成され、供給された空気は沸点の差を利用して純酸
素、純窒素、廃窒素などに分離される。廃窒素は配管８
を経由して前処理装置３に送られ、吸着剤の垂生をした
後配管９を経由して大気に放出される。純酸素は配管１
０を経由して、純窒素は配管１１を経由して、それぞれ
製品として回収される、第７図は前処理装置３の詳細フ
ローの一例を示す図である。運転サイクルは第１図に示
したように操作される。以下、吸着塔２１を中心に説明
する。予備吸着工程及び吸着工程では加圧空気は配管６
、弁２３、配管３５及び３１、吸着塔２１、配管３３、
弁２６、配管７を経由して深冷分離装置に供給される。Embodiment 1 FIG. 6 is a system diagram showing an embodiment of the air separation apparatus according to the present invention. In Figure 6, the air separation device is compressor 1.
, a cooler 2, a pre-PSA legal treatment device 3, a cold separation device 4, etc. The air introduced from piping 5 is pressurized by compressor 1, sent to pre-treatment device 3 via cooler 2 and piping 6, and after removing moisture and carbon dioxide, which are solidification components, via piping 7. It is then supplied to the cryogenic separator 4. The cryogenic separator 4 is composed of a heat exchanger, an expansion turbine, a rectification column, etc., and the supplied air is separated into pure oxygen, pure nitrogen, waste nitrogen, etc. using the difference in boiling point. Waste nitrogen is piped 8
The adsorbent is sent to the pretreatment device 3 via the pipe 9, where it is coated with adsorbent and then released into the atmosphere via the pipe 9. Pure oxygen is pipe 1
0, pure nitrogen passes through the pipe 11, and is recovered as a product. FIG. 7 is a diagram showing an example of a detailed flow of the pretreatment device 3. The operating cycle is operated as shown in FIG. Hereinafter, the adsorption tower 21 will be mainly explained. In the preliminary adsorption process and the adsorption process, pressurized air is supplied to pipe 6.
, valve 23, pipes 35 and 31, adsorption tower 21, pipe 33,
It is supplied to the cryogenic separator via the valve 26 and piping 7.

減圧工程では、吸着塔２１内の空気を配管３１、弁２４
、配管９を経由して大気に放出し、晧着塔２１内の圧力
を大気圧まで減圧する。パージ工程では、廃窒素を配管
８、弁２８、配管３３、吸着塔２１、配管゛３１、弁２
４、配管９を経由して大気に放出する。加圧工程では、
加圧空気を配管６、弁２３、配管３６、弁２５、配管３
１を経由して吸着塔２１に送シ、吸着塔２１内の圧力を
上昇させる。ここで、減圧工程、加圧工程及び予備吸着
工程では、廃窒素を配管３７、弁３０、配管３８を経由
して大気に放出する。配管７には圧力計３９及びガスサ
ンプリング口４０を設け、空気圧力Ｐ及び空気中の水分
及び炭酸ガス濃度の測定を行った。加圧速度の調整は圧
縮機１の吐出量及び弁２５の開度を調節して行い、加圧
時間は加圧工程において吸着塔２１及び２２の圧力が等
しくなるのに要する時間とした。なお、２７及び２９は
弁、３２及び３４は配管ぐある。In the pressure reduction step, the air in the adsorption tower 21 is transferred to the pipe 31 and the valve 24.
, and is discharged to the atmosphere via piping 9, and the pressure inside the immersion tower 21 is reduced to atmospheric pressure. In the purge process, waste nitrogen is transferred to pipe 8, valve 28, pipe 33, adsorption tower 21, pipe 31, valve 2
4. Release to the atmosphere via piping 9. In the pressurization process,
Pressurized air is connected to piping 6, valve 23, piping 36, valve 25, piping 3
1 to the adsorption tower 21, and the pressure inside the adsorption tower 21 is increased. Here, in the pressure reduction step, the pressurization step, and the preliminary adsorption step, waste nitrogen is released into the atmosphere via the pipe 37, valve 30, and pipe 38. A pressure gauge 39 and a gas sampling port 40 were installed in the pipe 7, and the air pressure P and the moisture and carbon dioxide concentrations in the air were measured. The pressurization speed was adjusted by adjusting the discharge amount of the compressor 1 and the opening degree of the valve 25, and the pressurization time was the time required for the pressures of the adsorption towers 21 and 22 to become equal in the pressurization step. In addition, 27 and 29 are valves, and 32 and 34 are piping.

吸着剤として活性アルミナを用い、吸着工程時（７）８
　Ｖ　＝　２０００ｈ−１、ｇ窒素流量／空気流量＝０
．４゜θ二　＝　０．１　ｍｉｎ、　　θ、＝　　１　
２ｍ１ｎ、　　θｂ　＝Ｑ、５ｍ１ｎ。Using activated alumina as an adsorbent, during the adsorption process (7) 8
V = 2000h-1, g nitrogen flow rate/air flow rate = 0
．． 4゜θ2 = 0.1 min, θ, = 1
2m1n, θb =Q, 5m1n.

θ７＝２４ｍｉｎ、空気圧力０．６　ＭＰａ、　　廃窒
素圧力０、１１　ＭＰａ、　空気温度２８ｃ、廃窒素温
度２６ｃの条件下で、θ、／θＴ及びＰ／Ｐｏ　　を変
化させ、配管７における炭酸ガス濃度及び配管１１にお
ける酸素濃度を測定した。下表に結果を示す。Under the conditions of θ7 = 24 min, air pressure 0.6 MPa, waste nitrogen pressure 0 and 11 MPa, air temperature 28 c, and waste nitrogen temperature 26 c, θ, /θT and P/Po were changed to determine the carbon dioxide concentration in pipe 7. And the oxygen concentration in the pipe 11 was measured. The results are shown in the table below.

この表より明らかなととくθ、／θＴ＝０．１２５　　
及びｐ／Ｐｏ＝０．９　　の条件下で炭酸ガスが十分に
除去され、また高純度窒素が得られることが確認された
。From this table, it is clear that θ, /θT=0.125
It was confirmed that carbon dioxide gas was sufficiently removed under the conditions of p/Po=0.9 and that high purity nitrogen was obtained.

実施例２ 第８図は本発明の他の実施例を示すものである。Example 2 FIG. 8 shows another embodiment of the invention.

第７図と異なる点は屏２５に代えて、−筒針４１及び流
量調節弁４２を設置した。配管７の圧力Ｐを検知し、調
節計４１では検知した圧力Ｐと設定圧力Ｐｏの比Ｐ／Ｐ
ｏの変化に応じて流量調節弁４２の開度を補正し、Ｐ／
Ｐｏが０，８５以上になるように制御するものである。The difference from FIG. 7 is that, in place of the folding screen 25, a cylinder needle 41 and a flow control valve 42 are installed. The pressure P in the pipe 7 is detected, and the controller 41 calculates the ratio P/P of the detected pressure P and the set pressure Po.
The opening degree of the flow rate control valve 42 is corrected according to the change in P/
It is controlled so that Po becomes 0.85 or more.

θｐ／θＴ＝０．１２５とし、他の条件は実施例１と同
一で運転したところ、配管７における炭酸ガス濃度はＩ
　Ｉ）ｐｍ　　以上配管１１における酸素濃度は５　ｐ
Ｉ）ｍ以下となった実施例３ 第９図は本発明の他の実施例を示し犬ものである。第７
図と異なる点は、弁２５に代えて、弁４３と絞り板４４
を設置した。θ、／θ丁＝０．１２５としＰ／Ｐｏ＝０
．９０になるように絞り板４４の径を設定し、他の条件
は実施例１と同一で運転を行った。When θp/θT = 0.125 and other conditions were the same as in Example 1, the carbon dioxide concentration in pipe 7 was I
I) pm The oxygen concentration in the pipe 11 is 5 p
I) Example 3 in which the temperature was below m Figure 9 shows another example of the present invention, which is a dog. 7th
The difference from the figure is that instead of the valve 25, a valve 43 and a throttle plate 44 are used.
was installed. θ, /θd=0.125 and P/Po=0
．． The diameter of the aperture plate 44 was set to 90 mm, and the other conditions were the same as in Example 1.

その結果、配管７における炭酸ガス濃度は１　ｐＩ）ｍ
以下、配管１１における酸素濃度５　ｐｐｍ、以下とな
った。As a result, the carbon dioxide concentration in pipe 7 is 1 pI)m
Thereafter, the oxygen concentration in the pipe 11 was 5 ppm or less.

本発明によれば、空気分離装置で製造される純酸素及び
純窒素の純度を低下させることなく、空気中の水分及び
炭酸ガスを効率的に除去することができる。According to the present invention, moisture and carbon dioxide in the air can be efficiently removed without reducing the purity of pure oxygen and pure nitrogen produced by the air separation device.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の運転サイクルを示す図、第２図はサイ
クル時間と炭酸ガ、ス除去性能の関係を示す図、第３図
は加圧速度と加圧時間とサイクル時間の比及び加圧工程
時の吸着塔出口空気圧力の関係を示す図、第４図は加圧
時間とサイクル時間の比と炭酸ガス濃度の関係を示す図
、第５図はカロ圧工程時の吸着塔出口空気圧力と酸素濃
度の関係を示す図、第６図は本発明に係る空気分離装置
の一実施例を示す系統図、第７図は本発明に係る前処理
装置の詳細フローの一例を示す系統図、第８図は本発明
に係る前処理装置の詳細フローの他の一例を示す系統図
、第９図は本発明に係る前処理装置の詳細フローの他の
一例を示す系統図である。 １・・・圧縮機、２・・・冷却器、３・・・ＰＳＡ法前
法理処理装置・・・深冷分離装置、２１．２２・・・吸
着塔。 め　２　目 す４７ｔＬ叶１４（４ｔ） め　３　口 ■　４め 菊　５　ｍ ’／１０ん工程β午−呪羞４否出口＠７＋Ｊｉ’：カ結
　ｔ　閃 詰　７　Ｈ 鯖　ｌFig. 1 is a diagram showing the operating cycle of the present invention, Fig. 2 is a diagram showing the relationship between cycle time and carbon dioxide gas and gas removal performance, and Fig. 3 is a diagram showing the ratio of pressurization speed, pressurization time, and cycle time, and A diagram showing the relationship between air pressure at the outlet of the adsorption tower during the pressure process, Figure 4 is a diagram showing the relationship between the ratio of pressurization time and cycle time, and carbon dioxide concentration, and Figure 5 shows the relationship between air pressure at the outlet of the adsorption tower during the pressure process. A diagram showing the relationship between pressure and oxygen concentration, FIG. 6 is a system diagram showing an embodiment of the air separation device according to the present invention, and FIG. 7 is a system diagram showing an example of the detailed flow of the pretreatment device according to the present invention. , FIG. 8 is a system diagram showing another example of the detailed flow of the preprocessing device according to the present invention, and FIG. 9 is a system diagram showing another example of the detailed flow of the preprocessing device according to the present invention. 1...Compressor, 2...Cooler, 3...Pre-PSA method processing device...Cryogenic separation device, 21.22...Adsorption tower. Me 2 Eyes 47tL Kano 14 (4t) Me 3 Mouth ■ 4th Chrysanthemum 5 m '/10n process β - Juji 4 negative exit @7 + Ji': Kakyu t Flashing 7 H Mackerel l

Claims (1)

【特許請求の範囲】 １、一方の搭において吸着圧力下で加圧空気を流通させ
て吸着剤によって水分及び炭酸ガスを除去する吸着工程
を行わせ、他の塔において吸着圧力から脱着圧力まで降
圧させる減圧工程、”脱着圧力下で廃窒素を流通させて
吸着剤を再生するパージ工程及び脱着圧力から吸着圧力
まで昇圧させる加圧工程を順に行わせ、これらを交互に
行わせることにより連続的に精製された加圧空気を得る
空気分離装置の前処理法において、一方の塔の加圧工程
時、他の塔の吸着圧力を設定された吸着圧力の０．７５
以上′に保持し、同時に加圧時間とサイクル時間の比が
０．２以下になるように加圧速度を調整することを特徴
とする空気分離装置の前処理方法。 ２、加圧工程の空気流入配管に設けた弁の開度を調節し
て加圧速度を調整することを特徴とする特許請求の範囲
第１項記載の空気分離装置の前処理方法。 ３、加圧工程の空気流入配管に設けた絞りにより加圧速
度を調整することを特徴とする特許請求の範囲第１項記
載の空気分離装置の前処理方法。 ４、加圧工程の空気流入配管に弁を設け、該配管内の圧
力を検知し、該検知値に応じた調節計の指示により前記
弁の開度を調節することによシ加圧速度を調整すること
を特徴とする特許請求の範囲第１項記載の空気分離装置
の前処理方法。[Claims] 1. An adsorption process is carried out in which pressurized air is passed under adsorption pressure in one tower to remove moisture and carbon dioxide by an adsorbent, and the pressure is lowered from the adsorption pressure to the desorption pressure in the other tower. A depressurization step to make the adsorbent regenerate by circulating waste nitrogen under desorption pressure, a purge step to regenerate the adsorbent by circulating waste nitrogen under desorption pressure, and a pressurization step to increase the pressure from the desorption pressure to the adsorption pressure are carried out in order, and these steps are performed alternately. In a pretreatment method for an air separation device to obtain purified pressurized air, during the pressurization process of one column, the adsorption pressure of the other column is set to 0.75 of the set adsorption pressure.
1. A pretreatment method for an air separation device, characterized in that the pressurization speed is maintained so that the ratio of the pressurization time to the cycle time is 0.2 or less. 2. The pretreatment method for an air separation device according to claim 1, characterized in that the pressurization speed is adjusted by adjusting the opening degree of a valve provided in the air inflow pipe in the pressurization step. 3. The pretreatment method for an air separation device according to claim 1, wherein the pressurization speed is adjusted by a throttle provided in the air inflow pipe in the pressurization step. 4. A valve is installed in the air inflow pipe for the pressurization process, the pressure inside the pipe is detected, and the pressurization speed is controlled by adjusting the opening degree of the valve according to the instructions from the controller according to the detected value. A pretreatment method for an air separation device according to claim 1, characterized in that the pretreatment method for an air separation device is adjusted.