JP2016097320A

JP2016097320A - Hydrogen purification method

Info

Publication number: JP2016097320A
Application number: JP2014233363A
Authority: JP
Inventors: 由直小宮; Yoshinao Komiya; 荒川　秩; Chitsu Arakawa; 秩荒川; 敏雄秋山; Toshio Akiyama; 保雄佐藤; Yasuo Sato; 登武政; Noboru Takemasa
Original assignee: Japan Pionics Ltd
Current assignee: Japan Pionics Ltd
Priority date: 2014-11-18
Filing date: 2014-11-18
Publication date: 2016-05-30

Abstract

PROBLEM TO BE SOLVED: To provide a hydrogen purification method for efficiently extracting pure hydrogen from a secondary side space by reducing an extraction amount of gas containing impurities not permeating through a fine palladium alloy pipe, by using a hydrogen purification apparatus in which an internal part of a cell is divided into a primary side space and the secondary side space by a pipe plate supporting the fine palladium alloy pipe whose one end is sealed and an opening end of the fine pipe, and in which hydrogen containing impurities is introduced from the primary side space and permeated through the fine palladium alloy pipe so that pure hydrogen can be extracted from the secondary side space.SOLUTION: Gas containing impurities not permeating through a fine palladium alloy pipe is removed from a primary side space at a flow rate of 0.00002-0.0002 times a value ab which is obtained by multiplying an introduction flow rate a of raw material hydrogen by a percentage content b(ppm) of the impurities contained in the raw material hydrogen.SELECTED DRAWING: Figure 3

Description

本発明は、パラジウム合金薄膜の水素ガス選択透過性を利用した水素精製方法に関し、詳細には、セルの一次側空間に導入する不純物を含む原料水素から、効率よく純水素を得ることが可能な水素精製方法に関する。 The present invention relates to a hydrogen purification method using hydrogen gas selective permeability of a palladium alloy thin film, and more specifically, it is possible to efficiently obtain pure hydrogen from raw material hydrogen containing impurities introduced into a primary space of a cell. The present invention relates to a hydrogen purification method.

従来から、半導体製造工程においては、高純度の水素ガスが雰囲気ガスとして多量に使用されている。このような水素ガスは、半導体の集積度の向上により不純物の濃度が極めて低濃度（ｐｐｂレベル以下）であることが要求される。
一方、高純度の水素を工業的に多量に製造する方法としては、メタノール、ジメチルエーテル、天然ガス、液化石油ガス等から水蒸気改質反応により得られる改質ガスを、深冷吸着法、圧力スイング法等により、水素と水素以外のガスに分離して水素を得る方法が知られている。 Conventionally, high-purity hydrogen gas has been used in a large amount as an atmospheric gas in a semiconductor manufacturing process. Such a hydrogen gas is required to have an extremely low impurity concentration (ppb level or less) due to an improvement in semiconductor integration.
On the other hand, as a method for industrially producing a large amount of high-purity hydrogen, a reformed gas obtained by a steam reforming reaction from methanol, dimethyl ether, natural gas, liquefied petroleum gas, etc. is subjected to a cryogenic adsorption method or a pressure swing method. For example, a method of obtaining hydrogen by separating it into hydrogen and a gas other than hydrogen is known.

深冷吸着法は、液化窒素を冷媒として極低温化された吸着材が充填された吸着筒に水素含有ガスを流通し、水素以外の不純物を除去する精製方法であり、圧力スイング法は、複数の吸着筒に水素含有ガスを順次流通するとともに、昇圧、不純物の吸着、不純物の脱着、及び吸着材の再生の各操作を繰返して、水素以外の不純物を除去する精製方法である。前記のような改質ガスには、水素のほか、一酸化炭素、二酸化炭素、メタン、窒素、水等が含まれるが、深冷吸着法、圧力スイング法では、これらの不純物を極めて低濃度（ｐｐｂレベル以下）になるまで除去することは困難であった。 The cryogenic adsorption method is a purification method in which a hydrogen-containing gas is circulated through an adsorption cylinder filled with an adsorbent that has been cryogenically cooled using liquefied nitrogen as a refrigerant to remove impurities other than hydrogen. This is a purification method in which a hydrogen-containing gas is sequentially circulated through the adsorption cylinder, and impurities other than hydrogen are removed by repeating the operations of pressure increase, impurity adsorption, impurity desorption, and adsorbent regeneration. The reformed gas as described above contains carbon monoxide, carbon dioxide, methane, nitrogen, water, etc. in addition to hydrogen. In the cryogenic adsorption method and the pressure swing method, these impurities are contained at a very low concentration ( It was difficult to remove until the ppb level or lower).

これに対して、極めて高純度の水素ガスを、比較的に少量で得る方法として、不純物を含む原料水素を、パラジウム合金の薄膜からなる水素分離膜に供給し、水素ガスの選択透過性を利用して水素のみを透過させて取出す方法が知られている。このような水素精製のための装置は、不純物を含む原料水素の導入口、純水素の取出口、及び該導入口と該取出口の間のガス流路中にパラジウム合金の薄膜を備えてなる水素精製装置であり、例えば特許文献１〜３に示すように、一端が封じられた複数本のパラジウム合金細管（水素分離膜）が、他の一端の開口部で管板に支持されてセル内に収納され、このパラジウム合金細管及び管板によってセル内が一次側空間（不純物を含む原料水素の供給側空間）及び二次側空間（純水素の取出し側空間）の二つの空間に仕切られた構成を有する水素精製装置である。 On the other hand, as a method for obtaining a very high-purity hydrogen gas in a relatively small amount, raw hydrogen containing impurities is supplied to a hydrogen separation membrane made of a palladium alloy thin film, and the selective permeability of hydrogen gas is used. Thus, a method is known in which only hydrogen is taken out and taken out. Such an apparatus for purifying hydrogen is provided with a raw material hydrogen inlet containing impurities, a pure hydrogen outlet, and a palladium alloy thin film in a gas flow path between the inlet and the outlet. A hydrogen refining device, for example, as shown in Patent Documents 1 to 3, a plurality of palladium alloy capillaries (hydrogen separation membranes) sealed at one end are supported by a tube plate at the opening at the other end, and inside the cell. The inside of the cell is partitioned into two spaces, a primary space (impurity source hydrogen supply space) and a secondary space (pure hydrogen extraction space) by the palladium alloy thin tube and tube sheet. A hydrogen purification apparatus having a configuration.

特開昭６２−１２８９０３号公報JP-A-62-128903 特開平１−１４５３０２号公報JP-A-1-145302 特開平１−１４５３０３号公報JP-A-1-145303

パラジウム合金の水素分離膜を利用した水素精製方法は、深冷吸着法、圧力スイング法と比較して、前述のように高純度の水素ガスが得られるほか、装置を小型化、簡素化できるという長所があるが、単位時間当たりの純水素の取出し量が少ないという短所がある。また、水素のみが一次側空間から二次側空間に透過するので、そのままではセルの一次側空間は不純物が蓄積し水素の分圧が低下して純水素の取出し量が低下する。そのため、水素分離膜（パラジウム合金細管）を透過しない不純物を含むガス（不純物を含む水素）を一次側空間から取出し、大気に放出するか、または回収して再利用しているが、このような不純物を含むガスの排出量は少ないことが好ましい。従って、本発明が解決しようとする課題は、不純物を含むガスの取出し量を低減し、純水素を効率よく二次側空間から取出すことができる水素精製方法を提供することである。 Compared with the cryogenic adsorption method and the pressure swing method, the hydrogen purification method using the hydrogen separation membrane of palladium alloy can obtain high-purity hydrogen gas as described above, and can reduce the size and simplify the device. There is an advantage, but there is a disadvantage that the extraction amount of pure hydrogen per unit time is small. Further, since only hydrogen permeates from the primary side space to the secondary side space, if it is left as it is, impurities accumulate in the primary side space, the partial pressure of hydrogen is reduced, and the amount of pure hydrogen taken out is reduced. Therefore, a gas containing impurities (hydrogen containing impurities) that does not permeate the hydrogen separation membrane (palladium alloy thin tube) is taken out from the primary space and released into the atmosphere or recovered and reused. It is preferable that the amount of gas containing impurities be small. Therefore, the problem to be solved by the present invention is to provide a hydrogen purification method capable of reducing the amount of extraction of gas containing impurities and efficiently removing pure hydrogen from the secondary side space.

本発明者らは、これらの課題を解決すべく鋭意検討した結果、前述のような水素精製方法において、パラジウム合金細管を透過しない不純物を含むガスを、原料水素に含まれる不純物の含有率に応じて、流量調節器等により流量制御しながら一次側空間から取出すことにより、不純物を含むガスの取出し量を低減できることを見出し、本発明の水素精製方法に到達した。 As a result of intensive studies to solve these problems, the present inventors determined that the gas containing impurities that do not permeate the palladium alloy capillaries in the hydrogen purification method as described above depends on the content of impurities contained in the raw material hydrogen. Thus, it has been found that by taking out from the primary space while controlling the flow rate with a flow rate controller or the like, the amount of gas containing impurities can be reduced, and the hydrogen purification method of the present invention has been reached.

すなわち本発明は、一端が封じられた複数本のパラジウム合金細管と、該細管の開口端部において該細管を支持する管板によって、内部が一次側空間と二次側空間に仕切られたセルに、不純物を含む原料水素を一次側空間から導入し、パラジウム合金細管を透過させて二次側空間から純水素を取出すとともに、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．００００２〜０．０００２倍の流量で、一次側空間から取出すことを特徴とする水素精製方法である。 That is, the present invention provides a cell in which the inside is partitioned into a primary side space and a secondary side space by a plurality of palladium alloy thin tubes sealed at one end and a tube plate that supports the thin tube at the open end of the thin tube. The raw material hydrogen containing impurities is introduced from the primary side space, permeated through the palladium alloy thin tube to take out pure hydrogen from the secondary side space, and the gas containing impurities that do not permeate the palladium alloy thin tube is introduced into the raw material hydrogen introduction flow rate a The hydrogen purification method is characterized in that it is extracted from the primary side space at a flow rate of 0.00002 to 0.0002 times the value ab obtained by multiplying the content rate b (ppm) of impurities contained in the raw material hydrogen.

本発明の水素精製方法は、複数本のパラジウム合金細管等によって、内部が一次側空間と二次側空間に仕切られたセルを有する水素精製装置において、パラジウム合金細管を透過しない不純物を含むガスを、原料水素に含まれる不純物の含有率に応じて、流量調節器等により流量制御しながら一次側空間から排出させるので、該不純物を含むガス（不純物を含む水素）の排出流量を最小限またはこれに近い量に抑制することができる。その結果、原料水素のロスを抑制し純水素を効率よく二次側空間から取出すことが可能となる。 The hydrogen purification method of the present invention is a hydrogen purification apparatus having a cell whose interior is partitioned into a primary side space and a secondary side space by a plurality of palladium alloy capillaries, etc., and containing a gas containing impurities that do not permeate the palladium alloy capillaries. Since the gas is discharged from the primary space while controlling the flow rate with a flow rate controller or the like according to the content of impurities contained in the raw material hydrogen, the discharge flow rate of the gas containing impurities (hydrogen containing impurities) is minimized or reduced. It can be suppressed to an amount close to. As a result, it is possible to suppress the loss of raw material hydrogen and efficiently extract pure hydrogen from the secondary side space.

本発明は、一端が封じられたパラジウム合金細管と該細管の開口端を支持する管板によってセルの内部が一次側空間と二次側空間に仕切られ、不純物を含む水素を一次側空間から導入し、パラジウム合金細管を透過させて二次側空間から純水素を取出す構成の水素精製装置による水素精製方法に適用される。また、本発明に適用される原料水素としては、メタノール、ジメチルエーテル、天然ガス、液化石油ガス等から水蒸気改質反応により得られる改質ガス、これらを予備的に精製したガス、あるいは工業用としてボンベ等に充填されている比較的に高純度の水素等が挙げられる。本発明により得られる極めて高純度の精製水素は、例えば半導体製造工程における雰囲気ガス（キャリアガス）として使用される。 In the present invention, the inside of the cell is partitioned into a primary side space and a secondary side space by a palladium alloy thin tube sealed at one end and a tube plate supporting the open end of the thin tube, and hydrogen containing impurities is introduced from the primary side space. In addition, the present invention is applied to a hydrogen purification method using a hydrogen purification apparatus having a configuration in which pure hydrogen is extracted from the secondary space through a palladium alloy thin tube. The raw material hydrogen applied to the present invention includes a reformed gas obtained by a steam reforming reaction from methanol, dimethyl ether, natural gas, liquefied petroleum gas, etc., a gas obtained by preliminarily purifying these, or a cylinder for industrial use. And relatively high-purity hydrogen filled in the like. The extremely high purity purified hydrogen obtained by the present invention is used as, for example, an atmospheric gas (carrier gas) in a semiconductor manufacturing process.

以下、本発明の水素精製方法を、図１〜図３に基づいて詳細に説明するが、本発明がこれらにより限定されるものではない。尚、図１は、本発明の水素精製方法に使用される水素精製装置のセル周辺部の一例を示す構成図である。図２は、図１の水素精製装置のセルの管板の位置における断面の一例を示す構成図である。また、図３は、本発明の水素精製方法に使用される水素精製装置の例を示す構成図である。 Hereinafter, although the hydrogen purification method of this invention is demonstrated in detail based on FIGS. 1-3, this invention is not limited by these. In addition, FIG. 1 is a block diagram which shows an example of the cell peripheral part of the hydrogen purification apparatus used for the hydrogen purification method of this invention. FIG. 2 is a block diagram showing an example of a cross section at the position of the tube plate of the cell of the hydrogen purification apparatus of FIG. Moreover, FIG. 3 is a block diagram which shows the example of the hydrogen purification apparatus used for the hydrogen purification method of this invention.

本発明の水素精製方法は、一端が封じられた複数本のパラジウム合金細管と、該細管の開口端部において該細管を支持する管板によって、内部が一次側空間と二次側空間に仕切られたセルに、不純物を含む原料水素を一次側空間から導入し、パラジウム合金細管を透過させて二次側空間から純水素を取出すとともに、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．００００２〜０．０００２倍の流量で、一次側空間から取出す水素精製方法である。 The hydrogen purification method of the present invention is divided into a primary space and a secondary space by a plurality of palladium alloy thin tubes sealed at one end and a tube plate supporting the thin tubes at the open end of the thin tube. The source hydrogen containing impurities is introduced into the cells from the primary side space, and pure hydrogen is taken out from the secondary side space through the palladium alloy thin tube, and a gas containing impurities that do not permeate the palladium alloy thin tube is introduced into the cell. In this hydrogen purification method, the flow rate is 0.00002 to 0.0002 times the value ab obtained by multiplying the introduction flow rate a by the impurity content b (ppm) contained in the raw material hydrogen.

本発明の水素精製方法を実施する際には、例えば、図１、図３に示すように、一端が封じられた複数本のパラジウム合金細管１と、該細管の開口端部において該細管を支持する管板２によって、セル３の内部が一次側空間３’と二次側空間３”に仕切られた構成を有し、不純物を含む原料水素を一次側空間３’に導入する原料水素供給口４、パラジウム合金細管１を透過した純水素を二次側空間３”から取出す純水素取出し口５、パラジウム合金細管１を透過しない不純物を含むガスを一次側空間３’から取出す不純物含有ガス取出し口６、及び該不純物含有ガス取出し口６の下流側に不純物を含むガスの流量を制御する流量調節器１０を備えた水素精製装置が使用される。 When carrying out the hydrogen purification method of the present invention, for example, as shown in FIG. 1 and FIG. 3, a plurality of palladium alloy capillaries 1 sealed at one end, and the capillaries are supported at the open ends of the capillaries. The raw material hydrogen supply port for introducing the raw material hydrogen containing impurities into the primary side space 3 ′ having a configuration in which the inside of the cell 3 is partitioned into a primary side space 3 ′ and a secondary side space 3 ″ by the tube plate 2 4. Pure hydrogen outlet 5 for taking out pure hydrogen that has passed through the palladium alloy thin tube 1 from the secondary side space 3 ″, and impurity containing gas outlet for taking out gas containing impurities that do not pass through the palladium alloy thin tube 1 from the primary side space 3 ′ 6 and a hydrogen purifier having a flow rate controller 10 for controlling the flow rate of the gas containing impurities on the downstream side of the impurity-containing gas outlet 6 is used.

本発明の水素精製方法において、不純物含有ガス取出し口６が設置されていない場合、または不純物含有ガス取出し口６からの不純物含有ガスの取出し量が少ない場合、セル３の一次側空間３’には不純物（ガス）が蓄積し、水素濃度が低下して、時間の経過とともに単位時間当たりの純水素の取出し量が減少するという不具合、一次側空間３’の圧力が高くなりすぎるという不具合が発生する虞がある。これとは反対に、不純物含有ガス取出し口６からの不純物含有ガスの取出し量が多すぎる場合は、大気に放出する不純物含有ガスの量、回収する不純物含有ガスの量等が多くなり、原料水素が無駄になるという不具合が発生する。 In the hydrogen purification method of the present invention, when the impurity-containing gas outlet 6 is not installed or when the amount of impurity-containing gas taken out from the impurity-containing gas outlet 6 is small, the primary space 3 ′ of the cell 3 has Impurities (gases) accumulate, the hydrogen concentration decreases, and there is a problem that the amount of pure hydrogen taken out per unit time decreases with time, and a problem that the pressure in the primary side space 3 ′ becomes too high. There is a fear. On the other hand, when the amount of the impurity-containing gas extracted from the impurity-containing gas outlet 6 is too large, the amount of the impurity-containing gas released to the atmosphere, the amount of the impurity-containing gas to be recovered, etc. increases. This causes a problem of waste.

本発明の水素精製方法においては、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに、原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．００００２〜０．０００２倍の流量、好ましくは０．００００３〜０．０００１倍の流量で、一次側空間から取出される。これにより、純水素を効率よく二次側空間から取出すことができる。例えば、原料水素に含まれる不純物の含有率が１０００ｐｐｍ（原料水素の純度：９９．９％）のとき、パラジウム合金細管を透過しない不純物を含むガスの排出量は、原料水素の導入量の２〜２０％、好ましくは３〜１０％に制御される。 In the hydrogen purification method of the present invention, a gas containing impurities that do not permeate the palladium alloy capillaries is obtained by multiplying the raw material hydrogen introduction flow rate a by the impurity content rate b (ppm) in the raw material hydrogen of 0. It is taken out from the primary space at a flow rate of 0.0002 to 0.0002 times, preferably 0.00003 to 0.0001 times. Thereby, pure hydrogen can be efficiently taken out from the secondary side space. For example, when the content of impurities contained in the raw material hydrogen is 1000 ppm (purity of raw material hydrogen: 99.9%), the discharge amount of the gas containing impurities that do not permeate the palladium alloy capillaries is 2 to 2 of the introduction amount of the raw material hydrogen. It is controlled to 20%, preferably 3 to 10%.

以下、本発明の水素精製方法に使用される水素精製装置の各構成部について詳細について説明する。
本発明の水素精製方法において使用されるパラジウム合金細管１は、図１に示すように、管板２側の一端に開口端部７を有し、反対側の一端に閉口端部８を有する管からなる。パラジウム合金細管１は、長さが通常２０〜２００ｃｍ、外径が通常１．０〜５．０ｍｍ、厚みが通常３０〜１００μｍである。また、パラジウム合金細管１は、１個のセルに対して３〜１００本使用される。これらの配置については特に制限がないが、隣接するパラジウム合金細管同士の間隔は、通常１．０〜２．５ｍｍとなるように設定される。 Hereinafter, each component of the hydrogen purification apparatus used in the hydrogen purification method of the present invention will be described in detail.
As shown in FIG. 1, a palladium alloy thin tube 1 used in the hydrogen purification method of the present invention has an open end 7 at one end on the tube plate 2 side and a closed end 8 at one end on the opposite side. Consists of. The palladium alloy thin tube 1 has a length of usually 20 to 200 cm, an outer diameter of usually 1.0 to 5.0 mm, and a thickness of usually 30 to 100 μm. Further, 3 to 100 palladium alloy thin tubes 1 are used for one cell. Although there is no restriction | limiting in particular about these arrangement | positioning, The space | interval of adjacent palladium alloy thin tubes is set so that it may become 1.0-2.5 mm normally.

前述のパラジウム合金細管１の構成成分としては、パラジウムと銅を主成分とする合金、パラジウムと銀を主成分とする合金、パラジウムと銀と金を主成分とする合金を例示することができる。これらの合金を用いる場合、パラジウム５０〜７０ｗｔ％と銅３０〜５０ｗｔ％との合金、パラジウム６０〜９０ｗｔ％と銀１０〜４０ｗｔ％との合金、パラジウム６０〜８０ｗｔ％と銀１０〜３７ｗｔ％と金３〜１０ｗｔ％の合金が好ましい。パラジウム合金はその他の金属を含んでいてもよいが、前記の金属は、通常は９５ｗｔ％以上、好ましくは９９ｗｔ％以上含有される。 Examples of the constituent components of the palladium alloy thin tube 1 include an alloy mainly composed of palladium and copper, an alloy mainly composed of palladium and silver, and an alloy mainly composed of palladium, silver and gold. When these alloys are used, an alloy of palladium 50 to 70 wt% and copper 30 to 50 wt%, an alloy of palladium 60 to 90 wt% and silver 10 to 40 wt%, palladium 60 to 80 wt%, silver 10 to 37 wt% and gold A 3-10 wt% alloy is preferred. The palladium alloy may contain other metals, but the metal is usually contained in an amount of 95 wt% or more, preferably 99 wt% or more.

本発明において使用される管板２は、通常は厚みが３〜３０ｍｍの円盤である。また、管板２の直径は、パラジウム合金細管１の径や本数等により異なるが、通常は１０〜２００ｍｍである。管板２には、予めパラジウム合金細管１を取付ける位置に、これを挿入するための貫通孔が設けられる。パラジウム合金細管１の管板２への支持は、溶接等により行なわれる。その際、パラジウム合金細管１の管表面を透過した純水素の流路空間を確保するために、必要に応じてパラジウム合金細管１の内部にコイル状のスプリングを挿入することもできる。尚、管板２はニッケル製であることが好ましい。 The tube sheet 2 used in the present invention is usually a disk having a thickness of 3 to 30 mm. Moreover, although the diameter of the tube sheet 2 changes with diameters, the number, etc. of the palladium alloy fine tube 1, it is 10-200 mm normally. The tube plate 2 is provided with a through-hole for inserting the palladium alloy thin tube 1 at a position where the tube plate 2 is previously attached. The palladium alloy thin tube 1 is supported on the tube plate 2 by welding or the like. At that time, a coiled spring can be inserted into the inside of the palladium alloy thin tube 1 as necessary in order to secure a pure hydrogen passage space that has passed through the surface of the palladium alloy thin tube 1. The tube sheet 2 is preferably made of nickel.

本発明において、不純物含有ガス取出し口６の位置は、管板２の位置より上流側であれば特に制限されることはないが、原料水素供給口４と離れた位置に設定されることが好ましい。そして、本発明の水素精製装置においては、図３に示すように、不純物含有ガス取出し口６の下流側に不純物を含むガスの流量を制御する流量調節器１０が備えられる。流量調節器１０としては、しぼり流量計（ベンチュリ流量計）、差圧流量計（オリフィス流量計）等を使用することができる。流量調節器１０の位置は、特に制限されることはないが、通常は不純物含有ガス取出し口６から５〜２００ｃｍ隔てて設けられる。 In the present invention, the position of the impurity-containing gas outlet 6 is not particularly limited as long as it is upstream from the position of the tube plate 2, but is preferably set at a position away from the raw material hydrogen supply port 4. . And in the hydrogen purification apparatus of this invention, as shown in FIG. 3, the flow regulator 10 which controls the flow volume of the gas containing an impurity is provided in the downstream of the impurity containing gas extraction port 6. As shown in FIG. As the flow controller 10, a squeezing flow meter (Venturi flow meter), a differential pressure flow meter (orifice flow meter), or the like can be used. The position of the flow controller 10 is not particularly limited, but is usually provided 5 to 200 cm away from the impurity-containing gas outlet 6.

本発明における水素精製は、図３に示すように、原料水素供給口４、純水素取出し口５、不純物含有ガス取出し口６を、外部の各配管に接続した後、セル３の内部をヒータ９により加熱するとともに、原料水素供給配管１１から原料水素を供給することにより行なわれる。水素精製の際のパラジウム合金細管１の温度は、通常は２５０〜５００℃、好ましくは３００〜４５０℃である。原料水素は加熱されたパラジウム合金細管１と接触し、水素のみがパラジウム合金細管１を透過し、純水素取出し口５、純水素の取出し配管１２を経由して回収される。 In the hydrogen purification in the present invention, as shown in FIG. 3, the raw material hydrogen supply port 4, the pure hydrogen extraction port 5, and the impurity-containing gas extraction port 6 are connected to external pipes, and the inside of the cell 3 is then connected to a heater 9. And by supplying raw material hydrogen from the raw material hydrogen supply pipe 11. The temperature of the palladium alloy thin tube 1 during the hydrogen purification is usually 250 to 500 ° C, preferably 300 to 450 ° C. The raw hydrogen comes into contact with the heated palladium alloy capillary 1 and only hydrogen passes through the palladium alloy capillary 1 and is recovered via the pure hydrogen outlet 5 and the pure hydrogen outlet pipe 12.

本発明において、水素精製の際は、一次側空間３’と二次側空間３”の圧力差を、０．５〜２ＭＰａに設定することが好ましい。また、原料水素供給口におけるガスと、不純物含有ガス取出し口におけるガスの温度差は、５０℃以内に設定することが好ましい。前記の範囲を外れる圧力差または温度差に設定した場合は、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．００００２〜０．０００２倍の流量で、一次側空間３’から取出すことが、処理操作の点で困難になる虞がある。 In the present invention, during hydrogen purification, the pressure difference between the primary side space 3 ′ and the secondary side space 3 ″ is preferably set to 0.5 to 2 MPa. The temperature difference of the gas at the contained gas outlet is preferably set within 50 ° C. When the pressure difference or the temperature difference is out of the above range, the gas containing impurities that do not permeate the palladium alloy capillaries is used as the raw material. Taking out from the primary side space 3 ′ at a flow rate of 0.00002 to 0.0002 times the value ab obtained by multiplying the hydrogen introduction flow rate a by the impurity content b (ppm) contained in the raw material hydrogen is a treatment operation. It may be difficult in terms.

次に、本発明を実施例により具体的に説明するが、本発明がこれらにより限定されるものではない。 EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited by these.

［実施例１］
（水素精製装置の製作）
直径２５ｍｍ、厚さ５ｍｍの円盤状のニッケル製管板２に、パラジウム、銀、及び金を主成分とする合金からなるパラジウム合金細管１（外径１．８ｍｍ、厚さ７０μｍ、長さ３００ｍｍ）３５本を、複数の同心円上に溶接した。次に、図１に示すような位置に、原料水素供給口４、不純物含有ガス取出し口５、及び純水素取出し口６を有する、内径２５ｍｍ、長さ７００ｍｍのＳＵＳ３１６Ｌ製セル３に、前記の管板２及びパラジウム合金細管１を収納した。 [Example 1]
(Production of hydrogen purification equipment)
Palladium alloy thin tube 1 (outer diameter 1.8 mm, thickness 70 μm, length 300 mm) made of an alloy mainly composed of palladium, silver, and gold on a disk-shaped nickel tube plate 2 having a diameter of 25 mm and a thickness of 5 mm 35 were welded onto a plurality of concentric circles. Next, the SUS316L cell 3 having an inner diameter of 25 mm and a length of 700 mm having the raw material hydrogen supply port 4, the impurity-containing gas outlet 5 and the pure hydrogen outlet 6 at the position shown in FIG. The plate 2 and the palladium alloy thin tube 1 were accommodated.

セル３の外側にヒータ９を設けた後、原料水素供給口４に原料水素の導入配管１１を、純水素取出し口５に純水素取出し配管１３を、不純物含有ガス取出し口６に不純物含有ガス回収配管１２を接続し、不純物含有ガス回収配管１２に流量調節器１０としてしぼり流量計を設置して、図３（１）に示すような構成の水素精製装置を製作した。 After the heater 9 is provided outside the cell 3, a raw hydrogen introduction pipe 11 is provided at the raw hydrogen supply port 4, a pure hydrogen extraction pipe 13 is provided at the pure hydrogen outlet 5, and an impurity containing gas is recovered at the impurity containing gas outlet 6. A pipe 12 was connected, and a squeezing flow meter was installed as the flow rate regulator 10 in the impurity-containing gas recovery pipe 12 to produce a hydrogen purifier having a configuration as shown in FIG.

（水素精製試験）
水素精製装置のセルの一次側の空間３’の内部の温度を６００℃に昇温するとともに水素を導入して、１０時間加熱処理を行なった。続いて水素精製装置のセルの一次側の空間３’の内部の温度を４２０℃まで低下させ、不純物（窒素、酸素、二酸化炭素等）を合計で約２００ｐｐｍ含む原料水素を、１４Ｌ／ｍｉｎの流量で原料水素供給口４から導入し、パラジウム合金細管を透過させて純水素取出し口６を経由して純水素を取出すとともに、パラジウム合金細管を透過しない不純物を含むガスを、０．１４Ｌ／ｍｉｎの流量（ａｂの値の０．００００５倍（ａ：１４、ｂ：２００））で、一次側空間から取出す水素の精製を行なった。１時間の処理を行なった結果、純水素取出し配管１３から約８３０Ｌの純水素が得られた。 (Hydrogen purification test)
The temperature inside the space 3 ′ on the primary side of the cell of the hydrogen purifier was raised to 600 ° C., hydrogen was introduced, and heat treatment was performed for 10 hours. Subsequently, the temperature inside the space 3 ′ on the primary side of the cell of the hydrogen purifier is lowered to 420 ° C., and raw hydrogen containing about 200 ppm in total (impurities (nitrogen, oxygen, carbon dioxide, etc.)) is supplied at a flow rate of 14 L / min. The raw material hydrogen supply port 4 introduces the hydrogen through the palladium alloy capillary tube and takes out pure hydrogen through the pure hydrogen outlet port 6, and a gas containing impurities that do not pass through the palladium alloy capillary tube is 0.14 L / min. The hydrogen extracted from the primary space was purified at a flow rate (0.00005 times the value of ab (a: 14, b: 200)). As a result of performing the treatment for 1 hour, about 830 L of pure hydrogen was obtained from the pure hydrogen extraction pipe 13.

尚、この間、純水素取出し配管１３から取出される純水素の流量は一定であった。また、一次側空間３’と二次側空間３”の圧力差は約１ＭＰａに、原料水素供給口におけるガスと、不純物含有ガス取出し口におけるガスの温度差は、２０℃以内に保持されていた。 During this time, the flow rate of pure hydrogen taken out from the pure hydrogen take-out pipe 13 was constant. In addition, the pressure difference between the primary side space 3 ′ and the secondary side space 3 ″ was about 1 MPa, and the temperature difference between the gas at the raw material hydrogen supply port and the gas at the impurity-containing gas outlet was kept within 20 ° C. .

［実施例２］
実施例１の水素精製試験において、不純物を合計で約２０００ｐｐｍ含む原料水素を用いたほかは実施例１と同様にして水素精製試験を行なった。パラジウム合金細管を透過しない不純物を含むガスの取出し流量は１．４Ｌ／ｍｉｎ(ａｂの値の０．００００５倍（ａ：１４、ｂ：２０００））であった。１時間の処理を行なった結果、純水素取出し配管１３から約７６０Ｌの純水素が得られた。 [Example 2]
In the hydrogen purification test of Example 1, a hydrogen purification test was conducted in the same manner as in Example 1 except that raw material hydrogen containing about 2000 ppm in total of impurities was used. The extraction flow rate of the gas containing impurities that did not permeate the palladium alloy thin tube was 1.4 L / min (0.00005 times the value of ab (a: 14, b: 2000)). As a result of performing the treatment for 1 hour, about 760 L of pure hydrogen was obtained from the pure hydrogen extraction pipe 13.

［実施例３］
実施例１の水素精製試験において、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．０００１倍の流量に設定したほかは実施例１と同様にして水素精製試験を行なった。パラジウム合金細管を透過しない不純物を含むガスの取出し流量は０．２８Ｌ／ｍｉｎ(ａ：１４、ｂ：２００）であった。１時間の処理を行なった結果、純水素取出し配管１３から約８２０Ｌの純水素が得られた。 [Example 3]
In the hydrogen purification test of Example 1, a gas containing impurities that do not permeate the palladium alloy thin tube is multiplied by 0.001 of a value ab obtained by multiplying the introduction flow rate a of the raw material hydrogen by the impurity content b (ppm) contained in the raw material hydrogen. A hydrogen purification test was conducted in the same manner as in Example 1 except that the flow rate was doubled. The extraction flow rate of the gas containing impurities that did not permeate the palladium alloy thin tube was 0.28 L / min (a: 14, b: 200). As a result of performing the treatment for 1 hour, about 820 L of pure hydrogen was obtained from the pure hydrogen extraction pipe 13.

以上のように、本発明においては、パラジウム合金細管を透過しない不純物を含むガスを、原料水素に含まれる不純物の含有率に応じて、少なくすることができるので、原料水素のロスを抑制し純水素を効率よく二次側空間から取出すことが可能である。 As described above, in the present invention, the gas containing impurities that do not permeate the palladium alloy capillaries can be reduced according to the content of impurities contained in the raw material hydrogen. It is possible to efficiently extract hydrogen from the secondary space.

水素精製装置のセル周辺部の一例を示す構成図Configuration diagram showing an example of a cell peripheral part of a hydrogen purifier 図１のパラジウム合金膜ユニットの管板の位置における断面の一例を示す構成図The block diagram which shows an example of the cross section in the position of the tube sheet of the palladium alloy membrane unit of FIG. 本発明の水素精製装置の例を示す構成図The block diagram which shows the example of the hydrogen purification apparatus of this invention

１パラジウム合金細管
２管板
３セル
３’セルの一次側空間
３”セルの二次側空間
４原料水素供給口
５純水素取出し口
６不純物含有ガス取出し口
７開口端部
８閉口端部
９ヒータ
１０流量調節器
１１原料水素の導入配管
１２不純物含有ガス回収配管
１３純水素取出し配管 DESCRIPTION OF SYMBOLS 1 Palladium alloy thin tube 2 Tube plate 3 Cell 3 'cell primary side space 3 "cell secondary side space 4 Raw material hydrogen supply port 5 Pure hydrogen outlet 6 Impurity containing gas outlet 7 Open end 8 Closed end 9 Heater 10 Flow controller 11 Raw material hydrogen introduction pipe 12 Impurity-containing gas recovery pipe 13 Pure hydrogen extraction pipe

Claims

一端が封じられた複数本のパラジウム合金細管と、該細管の開口端部において該細管を支持する管板によって、内部が一次側空間と二次側空間に仕切られたセルに、不純物を含む原料水素を一次側空間から導入し、パラジウム合金細管を透過させて二次側空間から純水素を取出すとともに、パラジウム合金細管を透過しない不純物を含むガスを、原料水素の導入流量ａに原料水素に含まれる不純物の含有率ｂ（ｐｐｍ）を乗じた値ａｂの０．００００２〜０．０００２倍の流量で、一次側空間から取出すことを特徴とする水素精製方法。 A raw material containing impurities in a plurality of palladium alloy thin tubes sealed at one end and a cell whose interior is partitioned into a primary side space and a secondary side space by a tube plate supporting the thin tube at the open end of the thin tube Hydrogen is introduced from the primary side space, pure hydrogen is taken out from the secondary side space through the palladium alloy thin tube, and a gas containing impurities that do not permeate the palladium alloy thin tube is included in the raw material hydrogen in the introduction flow rate a of the raw material hydrogen The hydrogen purification method is characterized in that it is extracted from the primary space at a flow rate of 0.00002 to 0.0002 times the value ab multiplied by the impurity content b (ppm).

一次側空間と二次側空間の圧力差を、０．５〜２ＭＰａに設定した請求項１に記載の水素精製方法。 The hydrogen purification method according to claim 1, wherein the pressure difference between the primary side space and the secondary side space is set to 0.5 to 2 MPa.

原料水素供給口におけるガスと、不純物含有ガス取出し口におけるガスの温度差を、５０℃以内に設定した請求項１に記載の水素精製方法。 The hydrogen purification method according to claim 1, wherein the temperature difference between the gas at the raw material hydrogen supply port and the gas at the impurity-containing gas outlet is set to 50 ° C. or less.