JP2013159529A

JP2013159529A - Fuel reforming apparatus equipped with reformer and method for scavenging interior of the reformer

Info

Publication number: JP2013159529A
Application number: JP2012023414A
Authority: JP
Inventors: Shohei Matsumoto; 祥平松本; Hideto Kubo; 秀人久保; Takashi Fuji; 敬司藤; Shuji Yumoto; 修士湯本; Masami Tomioka; 雅巳冨岡; Harumichi Nakanishi; 治通中西
Original assignee: Toyota Industries Corp; Toyota Motor Corp
Current assignee: Toyota Industries Corp; Toyota Motor Corp
Priority date: 2012-02-06
Filing date: 2012-02-06
Publication date: 2013-08-19

Abstract

PROBLEM TO BE SOLVED: To provide a fuel reforming apparatus that can be downsized and is equipped with a reformer containing at least a layer containing a nitrogen adsorbent, thereby being capable of preventing deterioration of an oxidation catalyst and a reforming catalyst caused by oxidation and scavenging the interior of the reformer using nitrogen separated from the layer containing the nitrogen adsorbent, and to provide a method for scavenging the interior of the reformer arranged inside the fuel reforming apparatus using the nitrogen separated from the layer containing the nitrogen adsorbent.SOLUTION: A fuel reforming apparatus includes a reformer at least containing a layer (A) containing a nitrogen adsorbent and a catalyst-containing layer (B).

Description

本発明は、改質器及びそれを備える燃料改質装置、並びにその改質器内を掃気する方法に関する。 The present invention relates to a reformer, a fuel reformer including the reformer, and a method for scavenging the interior of the reformer.

環境問題の取り組みの一つとして、新エネルギー技術である燃料電池が注目を集めている。この燃料電池は、水素と酸素とを電気化学的に反応させることにより化学エネルギーを電気エネルギーに変換させるものであってエネルギーの利用効率が高いという特徴を有している。燃料電池の燃料である水素は、原料ガス等の燃料から水素に改質する燃料改質装置又は改質器を利用することにより供給され得る。近年、燃料電池の研究開発が活発に行われていると同時に、水素燃料源の確実な確保という観点から、原料ガス等の燃料を水素に改質する燃料改質装置及び改質器の研究開発も盛んに行われている。 As an approach to environmental issues, fuel cells, a new energy technology, are attracting attention. This fuel cell is characterized in that chemical energy is converted into electrical energy by electrochemically reacting hydrogen and oxygen, and the energy utilization efficiency is high. Hydrogen, which is the fuel of the fuel cell, can be supplied by using a fuel reformer or reformer that reforms fuel such as a raw material gas into hydrogen. In recent years, research and development of fuel cells have been actively carried out, and at the same time, research and development of fuel reformers and reformers that reform raw gas and other fuels into hydrogen from the perspective of ensuring a secure hydrogen fuel source. It is also actively performed.

例えば、特許文献１には、燃料を蒸発させる蒸発器と、水蒸気を含む燃料ガスを部分酸化させその発熱で前記燃料ガスを、水素を含む改質ガスに改質する燃焼・改質触媒が充填された部分酸化改質器と、蒸発器の上流側にパージ用空気を供給するパージ空気供給ラインと、部分酸化改質器に空気を供給する改質空気供給ラインと、前記各空気供給ラインの空気流量を制御する流量制御器とを備え、運転停止後に、前記燃料ガスの供給を停止したままパージ空気供給ラインから空気を間欠的に供給し、これにより前記触媒の過熱を抑制しながら前記部分酸化改質器内の残留ガスを掃気する、ことを特徴とする燃料改質装置が提案されている。特許文献１によると、発明の燃料改質装置とその停止方法は、特別な機器やユーティリィティを必要とせず、運転停止後に装置内に残留する燃料ガスおよび改質ガスを安全に掃気して処理することができ、かつ改質触媒及び燃料電池の被毒を防止でき、車載に適したコンパクト化が容易である、等の優れた効果を有すると記載されている。また、特許文献２には、供給された水を気化して水蒸気を発生させる水蒸気生成器と、炭化水素を含む原燃料を供給する原燃料供給部と、前記原燃料と前記水蒸気とを含む混合ガスから水素含有ガスを生成する改質器とを少なくとも備えてなる水素含有ガス生成装置の運転停止時に、前記水蒸気生成器内部に残存する前記水を前記水素含有ガス生成装置の外部に排出する工程と、前記水素含有ガス生成装置を一体として密閉する工程とを含む水素含有ガス生成装置の運転方法が提案されている。特許文献２によると、本発明の目的は、運転停止時に水素含有ガス生成装置内部の故障や劣化が発生しない運転方法を提供する点にあると記載されている。さらに、特許文献３には、改質触媒を担持し、原燃料、水蒸気、空気を混合・反応させることにより水素リッチな改質ガスを生成する燃料改質部、燃料改質部で生成された改質ガスを燃料極に、空気を空気極に供給し、燃料極と空気極の間の電解質層で発電を行う燃料電池本体を有する改質型燃料電池システムにおいて、空気から窒素を分離するガス分離装置を備え、システム停止時に、前記ガス分離装置で分離した窒素を前記燃料改質部に充填する窒素パージを行うことを特徴とする改質型燃料電池システムが提案されている。特許文献３によると、改質触媒を担持し、原燃料、水蒸気、空気を混合・反応させることにより水素リッチな改質ガスを生成する燃料改質部、燃料改質部で生成された改質ガスを燃料極に、空気を空気極に供給し、燃料極と空気極の間の電解質層で発電を行う燃料電池本体を有する改質型燃料電池システムにおいて、空気から窒素を分離するガス分離装置を備え、システム停止時に、前記ガス分離装置で分離した窒素を前記燃料改質部に充填する窒素パージを行うようにしたので、空気中より分離精製した窒素を用いて窒素パージできるようになり、システム内に窒素貯蔵タンクを設ける必要が無くなりシステムを小型軽量化することができるとともに、外部より窒素貯蔵タンクに窒素を補充する必要がないため、燃料電池システムの保守工数を削減することができるという効果があると記載されている。 For example, Patent Document 1 is filled with an evaporator that evaporates fuel, and a combustion / reforming catalyst that partially oxidizes a fuel gas containing water vapor and reforms the fuel gas into a reformed gas containing hydrogen by the generated heat. The partial oxidation reformer, the purge air supply line for supplying purge air to the upstream side of the evaporator, the reformed air supply line for supplying air to the partial oxidation reformer, and the air supply lines. A flow rate controller for controlling the air flow rate, and after the operation is stopped, the air is intermittently supplied from the purge air supply line while the supply of the fuel gas is stopped, thereby suppressing overheating of the catalyst. There has been proposed a fuel reformer characterized by scavenging residual gas in an oxidation reformer. According to Patent Document 1, the fuel reforming apparatus and its stopping method of the invention do not require special equipment or utilities, and safely scavenge and process the fuel gas and reformed gas remaining in the apparatus after the operation is stopped. The reforming catalyst and the fuel cell can be prevented from being poisoned, and it is described as having excellent effects such as being easy to make compact suitable for in-vehicle use. Further, Patent Document 2 discloses a steam generator that generates steam by vaporizing supplied water, a raw fuel supply unit that supplies raw fuel containing hydrocarbons, and a mixture that includes the raw fuel and the steam. A step of discharging the water remaining in the steam generator to the outside of the hydrogen-containing gas generator when the operation of the hydrogen-containing gas generator comprising at least a reformer that generates a hydrogen-containing gas from the gas is stopped. And a method for operating the hydrogen-containing gas generating device, including the step of sealing the hydrogen-containing gas generating device together. According to Patent Document 2, it is described that an object of the present invention is to provide an operation method that does not cause failure or deterioration in the hydrogen-containing gas generation device when operation is stopped. Furthermore, in Patent Document 3, a reforming catalyst is supported, and a fuel reforming unit that generates a hydrogen-rich reformed gas by mixing and reacting raw fuel, water vapor, and air is generated in the fuel reforming unit. Gas for separating nitrogen from air in a reformed fuel cell system having a fuel cell body that supplies reformed gas to the fuel electrode, air to the air electrode, and generates electricity in the electrolyte layer between the fuel electrode and air electrode There has been proposed a reforming fuel cell system that includes a separation device and performs nitrogen purge for filling the fuel reforming portion with nitrogen separated by the gas separation device when the system is stopped. According to Patent Document 3, a reforming catalyst is supported, a fuel reforming section that generates a hydrogen-rich reformed gas by mixing and reacting raw fuel, water vapor, and air, and a reforming that is generated in the fuel reforming section. A gas separation device that separates nitrogen from air in a reformed fuel cell system having a fuel cell body that supplies gas to a fuel electrode, air to an air electrode, and generates power in an electrolyte layer between the fuel electrode and the air electrode When the system is shut down, nitrogen purge is performed to fill the fuel reformer with nitrogen separated by the gas separation device, so that nitrogen can be purged using nitrogen separated and purified from the air, Since there is no need to install a nitrogen storage tank in the system, the system can be reduced in size and weight, and it is not necessary to replenish the nitrogen storage tank from the outside. It is described that there is an effect that it is possible to reduce.

しかしながら、水素燃料源の確実な確保という観点から、原料ガス等の燃料を水素に改質する燃料改質装置及び改質器の更なる改良が望まれているのが現状である。 However, from the viewpoint of ensuring a hydrogen fuel source, further improvement of the fuel reformer and reformer for reforming fuel such as raw material gas into hydrogen is desired.

特開２００３−１０４７０７号公報JP 2003-104707 A 特開２００３−３０６３０９号公報JP 2003-306309 A 特開２００３−１６３０２４号公報Japanese Patent Laid-Open No. 2003-163024

本発明は、窒素吸着剤含有層と触媒含有層とが少なくとも含まれる改質器を備えることによって、酸化触媒及び改質触媒の酸化による劣化を防止することができ、かつ、窒素吸着剤含有層から脱離された窒素を用いて改質器内を掃気することができる小型化が可能である燃料改質装置を提供することを目的とする。さらには、本発明は、窒素吸着剤含有層から脱離された窒素を用いて、燃料改質装置に備えられる改質器内を掃気する方法を提供することを目的とする。 The present invention includes a reformer including at least a nitrogen adsorbent-containing layer and a catalyst-containing layer, whereby the oxidation catalyst and deterioration of the reforming catalyst due to oxidation can be prevented, and the nitrogen adsorbent-containing layer An object of the present invention is to provide a fuel reformer that can be downsized and can scavenge the interior of the reformer using nitrogen desorbed from the reactor. Furthermore, an object of the present invention is to provide a method of scavenging the inside of a reformer provided in a fuel reformer using nitrogen desorbed from a nitrogen adsorbent-containing layer.

上記目的を達成するための手段は、以下の第（１）項〜第（８）項である。
（１）窒素吸着剤含有層（Ａ）と、触媒含有層（Ｂ）とが少なくとも含まれる改質器を備える、燃料改質装置。
（２）その触媒含有層（Ｂ）が、酸化触媒含有層（Ｂ１）と改質触媒含有層（Ｂ２）とから構成される、第（１）項に記載の燃料改質装置。
（３）燃料及び空気の流れ方向の上流側から順に、その窒素吸着剤含有層（Ａ）と、その酸化触媒含有層（Ｂ１）と、その改質触媒含有層（Ｂ２）とが配設される、第（２）項に記載の燃料改質装置。
（４）その窒素吸着剤含有層（Ａ）と、その酸化触媒含有層（Ｂ１）との間に断熱性保持具が配設される、第（３）項に記載の燃料改質装置。
（５）前記窒素吸着剤含有層（Ａ）が燃料及び空気の流れ方向の最上流側に配設される、第（１）項〜第（４）項のいずれか１項に記載の燃料改質装置。
（６）燃料及び空気の流れ方向の上流側から順に、その酸化触媒含有層（Ｂ１）と、その改質触媒含有層（Ｂ２）と、その窒素吸着剤含有層（Ａ）とが配設される、第（２）項に記載の燃料改質装置。
（７）その酸化触媒含有層（Ｂ１）が燃料及び空気の流れ方向の最上流側に配設される、第（２）項又は第（６）項に記載の燃料改質装置。
（８）第（１）項〜第（７）項のいずれか１項に記載の燃料改質装置において、その窒素吸着剤含有層（Ａ）から脱離された窒素を用いて、その改質器内を掃気する方法。 Means for achieving the above object are the following items (1) to (8).
(1) A fuel reformer including a reformer including at least a nitrogen adsorbent-containing layer (A) and a catalyst-containing layer (B).
(2) The fuel reformer according to item (1), wherein the catalyst-containing layer (B) is composed of an oxidation catalyst-containing layer (B1) and a reforming catalyst-containing layer (B2).
(3) The nitrogen adsorbent-containing layer (A), the oxidation catalyst-containing layer (B1), and the reforming catalyst-containing layer (B2) are disposed in order from the upstream side in the fuel and air flow direction. The fuel reformer according to item (2).
(4) The fuel reformer according to item (3), wherein a heat insulating holder is disposed between the nitrogen adsorbent-containing layer (A) and the oxidation catalyst-containing layer (B1).
(5) The fuel modification according to any one of (1) to (4), wherein the nitrogen adsorbent-containing layer (A) is disposed on the most upstream side in the flow direction of fuel and air. Quality equipment.
(6) The oxidation catalyst-containing layer (B1), the reforming catalyst-containing layer (B2), and the nitrogen adsorbent-containing layer (A) are disposed in order from the upstream side in the fuel and air flow direction. The fuel reformer according to item (2).
(7) The fuel reformer according to (2) or (6), wherein the oxidation catalyst-containing layer (B1) is disposed on the most upstream side in the flow direction of fuel and air.
(8) In the fuel reformer according to any one of items (1) to (7), reforming is performed using nitrogen desorbed from the nitrogen adsorbent-containing layer (A). A method of scavenging inside the vessel.

本発明によれば、窒素吸着剤含有層と触媒含有層とが少なくとも含まれる改質器が備えられることによって、酸化触媒及び改質触媒の酸化による劣化を防止することができ、かつ、窒素吸着剤含有層から脱離された窒素を用いて改質器内を掃気することができる小型の燃料改質装置が提供され、また、窒素吸着剤含有層から脱離された窒素を用いて改質器内を掃気する方法が提供される。 According to the present invention, since the reformer including at least the nitrogen adsorbent-containing layer and the catalyst-containing layer is provided, the oxidation catalyst and the deterioration of the reforming catalyst due to oxidation can be prevented, and the nitrogen adsorption Provided is a small fuel reformer capable of scavenging the inside of the reformer using nitrogen desorbed from the adsorbent-containing layer, and reforming using nitrogen desorbed from the nitrogen adsorbent-containing layer A method of scavenging the vessel is provided.

図１は、本発明の燃料改質装置が備える改質器の１つの態様である、改質器１００を示す図である。FIG. 1 is a view showing a reformer 100 which is one embodiment of the reformer provided in the fuel reformer of the present invention. 図２は、本発明の燃料改質装置が備える改質器の１つの態様である、改質器２００を示す図である。FIG. 2 is a diagram showing a reformer 200 that is one embodiment of the reformer provided in the fuel reformer of the present invention. 図３は、本発明の燃料改質装置が備える改質器の１つの態様である、改質器３００を示す図である。FIG. 3 is a diagram showing a reformer 300 which is one embodiment of the reformer provided in the fuel reformer of the present invention. 図４は、運転時（燃料及び空気の供給時）及び停止時（燃料及び空気の供給停止時）における、本発明の燃料改質装置が備える改質器の１つの態様である改質器１００の温度変化を示す図である。FIG. 4 shows a reformer 100 which is one embodiment of the reformer provided in the fuel reformer of the present invention during operation (when fuel and air are supplied) and when stopped (when supply of fuel and air is stopped). It is a figure which shows the temperature change of. 図５は、従来の燃料改質装置が備える改質器５００を示す図である。FIG. 5 is a diagram showing a reformer 500 provided in a conventional fuel reformer. 図６は、運転時（燃料及び空気の供給時）及び停止時（燃料及び空気の供給停止時）における、従来の燃料改質装置が備える改質器５００の温度変化を示す図である。FIG. 6 is a diagram illustrating a temperature change of the reformer 500 included in the conventional fuel reformer during operation (when supplying fuel and air) and when stopped (when supply of fuel and air is stopped). 図７は、本発明の燃料改質装置のシステム構成図である。FIG. 7 is a system configuration diagram of the fuel reformer of the present invention. 図８は、従来の燃料改質装置のシステム構成図である。FIG. 8 is a system configuration diagram of a conventional fuel reformer.

（１）燃料改質装置
本発明による燃料改質装置は、窒素吸着剤含有層（Ａ）と、触媒含有層（Ｂ）とが少なくとも含まれる改質器を備えることを特徴とし、触媒含有層（Ｂ）は酸化触媒含有層（Ｂ１）と改質触媒含有層（Ｂ２）とから構成されることが好ましい。運転時（燃料及び空気の供給時）よりも停止時（燃料及び空気の供給停止時）に高温になる箇所（改質触媒含有層（Ｂ２）の下流側、酸化触媒含有層（Ｂ１）の上流側等）に窒素吸着剤含有層（Ａ）を配設することが好ましい。本発明による燃料改質装置は、窒素吸着剤含有層（Ａ）と、触媒含有層（Ｂ）とが少なくとも含まれる改質器を備えることによって、酸化触媒及び改質触媒の酸化による劣化を防止することができ、かつ、窒素吸着剤含有層から脱離された窒素を用いて改質器内を掃気することができ、装置の小型化が可能となる。そして、本発明による燃料改質装置は、窒素吸着剤含有層（Ａ）と、触媒含有層（Ｂ）とが少なくとも含まれる改質器を備えることによって、燃料改質装置、特には部分酸化型燃料改質装置の停止時（燃料及び空気の供給停止時）に改質器内を掃気するためにパージ空気供給ライン、不活性ガスタンク、窒素ガスの貯蔵タンク等を設ける必要はない。パージ空気供給ラインを設けると酸化触媒及び改質触媒の酸化による劣化を防止することができず、不活性ガスタンク、窒素ガスの貯蔵タンク等を設けると設備が大型になって小型化が不可能となる。運転（燃料及び空気の供給）後、しばらくの間は、窒素吸着剤含有層（Ａ）が窒素を吸着することによりガス状の燃料及び酸素の分圧が大きくなり、それによって反応速度が向上して反応率も向上する。停止（燃料及び空気の供給停止）後、更に放置すると改質器内の気体温度が下がって(窒素吸着剤含有層（Ａ）の温度が下がって窒素を吸着して)、改質器の内圧が下がり、酸素が流入する可能性があるが、改質触媒が不活性な温度まで低下した段階のため（すなわち、酸素が改質触媒に悪影響するのは活性温度状態の場合のみであるため）問題になることはない。 (1) Fuel reformer The fuel reformer according to the present invention comprises a reformer including at least a nitrogen adsorbent-containing layer (A) and a catalyst-containing layer (B), and the catalyst-containing layer (B) is preferably composed of an oxidation catalyst-containing layer (B1) and a reforming catalyst-containing layer (B2). Locations that are hotter than when operating (when supplying fuel and air) (when stopping supplying fuel and air) (downstream of the reforming catalyst-containing layer (B2), upstream of the oxidation catalyst-containing layer (B1)) The nitrogen adsorbent-containing layer (A) is preferably disposed on the side or the like. The fuel reformer according to the present invention includes a reformer including at least a nitrogen adsorbent-containing layer (A) and a catalyst-containing layer (B), thereby preventing deterioration of the oxidation catalyst and the reforming catalyst due to oxidation. In addition, the inside of the reformer can be scavenged using nitrogen desorbed from the nitrogen adsorbent-containing layer, and the apparatus can be downsized. The fuel reforming apparatus according to the present invention includes a reformer including at least the nitrogen adsorbent-containing layer (A) and the catalyst-containing layer (B), thereby providing a fuel reforming apparatus, particularly a partial oxidation type. There is no need to provide a purge air supply line, an inert gas tank, a nitrogen gas storage tank or the like in order to scavenge the interior of the reformer when the fuel reformer is stopped (when the supply of fuel and air is stopped). If a purge air supply line is provided, the oxidation catalyst and reforming catalyst cannot be prevented from being deteriorated by oxidation. If an inert gas tank, a nitrogen gas storage tank, etc. are provided, the equipment becomes large and cannot be reduced in size. Become. For some time after operation (supply of fuel and air), the nitrogen adsorbent-containing layer (A) adsorbs nitrogen to increase the partial pressure of gaseous fuel and oxygen, thereby improving the reaction rate. The reaction rate is also improved. If it is allowed to stand after stopping (fuel and air supply stop), the gas temperature in the reformer will decrease (the temperature of the nitrogen adsorbent-containing layer (A) will decrease and adsorb nitrogen), and the internal pressure of the reformer And oxygen may flow in, but because the reforming catalyst has fallen to an inactive temperature (ie, oxygen only has an adverse effect on the reforming catalyst only in the active temperature state) There is no problem.

本発明による燃料改質装置は、本発明の改質器を少なくとも備えれば特に限定されることはないが、燃料改質装置の他の構成要素として、燃料タンク、空気タンク、蒸発器、混合器、熱交換器、ＣＯ除去器、改質空気供給ライン、空気、燃料及び水蒸気の流量調節弁、液体ポンプ、三方弁等が備えられてもよい。燃料改質装置の他の構成要素の燃料タンク、空気タンク、蒸発器、混合器、熱交換器、ＣＯ除去器、改質空気供給ライン、空気、燃料及び水蒸気の流量調節弁、液体ポンプ、及び三方弁は公知のものでよい。 The fuel reformer according to the present invention is not particularly limited as long as it includes at least the reformer of the present invention, but as other components of the fuel reformer, a fuel tank, an air tank, an evaporator, a mixing device A heat exchanger, a CO exchanger, a reforming air supply line, a flow control valve for air, fuel and steam, a liquid pump, a three-way valve, and the like may be provided. Fuel tanks, air tanks, evaporators, mixers, heat exchangers, CO removers, reformed air supply lines, air, fuel and steam flow control valves, liquid pumps, and other components of the fuel reformer The three-way valve may be a known one.

本発明による燃料改質装置が備える改質器は、窒素吸着剤含有層（Ａ）と、触媒含有層（Ｂ）とが少なくとも含まれ、好ましくは触媒含有層（Ｂ）が酸化触媒含有層（Ｂ１）と改質触媒含有層（Ｂ２）とから構成されて、水（水蒸気）及び／又は酸素を原料ガス等の燃料と反応させて水素（改質ガス）に改質できれば特に限定されることはない。改質反応は、例えば、自己熱改質反応、部分酸化型反応等を挙げることができるが、部分酸化型反応が好ましい。 The reformer provided in the fuel reformer according to the present invention includes at least a nitrogen adsorbent-containing layer (A) and a catalyst-containing layer (B), and preferably the catalyst-containing layer (B) is an oxidation catalyst-containing layer ( B1) and the reforming catalyst-containing layer (B2) are particularly limited as long as they can be reformed to hydrogen (reformed gas) by reacting water (steam) and / or oxygen with a fuel such as a raw material gas. There is no. Examples of the reforming reaction include an autothermal reforming reaction and a partial oxidation reaction, and a partial oxidation reaction is preferable.

部分酸化型反応とは、原料ガス等の燃料を酸化させて改質反応を進行させる方法であり、比較的立ち上げ時間が短く、燃料改質装置をコンパクトに設計することができる。部分酸化型改質では空気が原料ガス等の燃料に添加される。反応を進めるための温度を確保するため、熱のロス等において適宜添加量は決定される。部分酸化型反応の反応温度は、水蒸気改質反応の場合と同様、４５０℃〜９００℃の範囲であり、好ましくは５００℃〜８５０℃の範囲であり、さらに好ましくは５５０℃〜８００℃の範囲である。原料ガス等の燃料が液体の場合、この時の空間速度（ＬＨＳＶ）は、好ましくは０．１〜３０の範囲で選ばれる。 The partial oxidation type reaction is a method in which a reforming reaction proceeds by oxidizing a fuel such as a raw material gas, and the start-up time is relatively short, and the fuel reforming apparatus can be designed compactly. In partial oxidation reforming, air is added to a fuel such as a raw material gas. In order to secure a temperature for proceeding the reaction, the amount added is appropriately determined in terms of heat loss and the like. The reaction temperature of the partial oxidation reaction is in the range of 450 ° C. to 900 ° C., preferably in the range of 500 ° C. to 850 ° C., more preferably in the range of 550 ° C. to 800 ° C., as in the case of the steam reforming reaction. It is. When the fuel such as the raw material gas is liquid, the space velocity (LHSV) at this time is preferably selected in the range of 0.1-30.

窒素吸着剤含有層（Ａ）は窒素吸着剤を少なくとも含有すれば、特に限定されることはない。窒素吸着剤は、特に限定されることはないが、例えばゼオライト等が挙げられる。ゼオライトは合成ゼオライトでもよく、塊状ゼオライトでもよい。塊状ゼオライトはリチウムで交換してもよく、必要に応じてさらに、周期律表のIA、IIA、IIIAおよびIIIB族、ランタニド系または希土類金属の三価のイオン、亜鉛(II)イオン、第二銅(II)イオン、クロム(III)イオン、第二鉄(III)イオン、アンモニウムイオンおよび／またはヒドロニウムイオンを含む群から選択される１つまたは複数のイオンで交換してもよい。 The nitrogen adsorbent-containing layer (A) is not particularly limited as long as it contains at least a nitrogen adsorbent. The nitrogen adsorbent is not particularly limited, and examples thereof include zeolite. The zeolite may be a synthetic zeolite or a bulk zeolite. The bulk zeolite may be exchanged with lithium, and if necessary, the group IA, IIA, IIIA and IIIB of the periodic table, lanthanide-based or rare earth metal trivalent ions, zinc (II) ions, cupric copper Exchange may be made with one or more ions selected from the group comprising (II) ions, chromium (III) ions, ferric (III) ions, ammonium ions and / or hydronium ions.

触媒含有層（Ｂ）は触媒を少なくとも含有すれば、特に限定されることはない。触媒含有層（Ｂ）は上記のとおり酸化触媒含有層（Ｂ１）と改質触媒含有層（Ｂ２）とから構成されることが好ましく、酸化触媒含有層（Ｂ１）は酸化触媒を少なくとも含有すれば、特に限定されることはない。酸化触媒は、特に限定されることはないが、例えば、ルテニウム系触媒、白金系触媒、ロジウム系触媒等が挙げられ、また、これらにイリジウム、パラジウム、レニウム等の貴金属やニッケル、クロム、銅、鉄等の遷移金属を添加した貴金属系酸化触媒等も挙げられる。改質触媒含有層（Ｂ２）は改質触媒を少なくとも含有すれば、特に限定されることはない。改質触媒は、特に限定されることはないが、例えば、ニッケル、コバルト、鉄、ルテニウム、ロジウム、イリジウム、白金等のＶＩＩＩ族金属を代表例とする金属触媒、ペロブスカイトやスピネル型の酸化物触媒等が挙げられる。各触媒含有層は例えば、コージェライトや金属からなるハニカム基材に各触媒を担持させて形成される。複数の触媒を１つの基材に担持させてもよいし、別々の基材に担持させて、所望の順に配置してもよい。 The catalyst-containing layer (B) is not particularly limited as long as it contains at least a catalyst . As described above, the catalyst-containing layer (B) is preferably composed of the oxidation catalyst-containing layer (B1) and the reforming catalyst-containing layer (B2), and the oxidation catalyst-containing layer (B1) contains at least an oxidation catalyst. There is no particular limitation. The oxidation catalyst is not particularly limited, and examples thereof include a ruthenium-based catalyst, a platinum-based catalyst, a rhodium-based catalyst, and the like, and these include noble metals such as iridium, palladium, rhenium, nickel, chromium, copper, Examples include noble metal-based oxidation catalysts to which transition metals such as iron are added. The reforming catalyst-containing layer (B2) is not particularly limited as long as it contains at least the reforming catalyst. The reforming catalyst is not particularly limited. For example, a metal catalyst, typically a group VIII metal such as nickel, cobalt, iron, ruthenium, rhodium, iridium, platinum, or a perovskite or spinel type oxide catalyst. Etc. Each catalyst-containing layer is formed, for example, by supporting each catalyst on a honeycomb substrate made of cordierite or metal. A plurality of catalysts may be supported on one base material, or may be supported on separate base materials and arranged in a desired order.

以下、図１〜図８を参照しながら、本発明による燃料改質装置及び本発明による燃料改質装置が備える改質器について更に詳細に説明をする。なお、本発明による燃料改質装置は、本発明の目的及び主旨を逸脱しない範囲で、図７の本発明の実施の形態に限定されるものではない。そして、本発明による燃料改質装置が備える改質器は、本発明の目的及び主旨を逸脱しない範囲で、図１〜図３の本発明の実施の形態に限定されるものではない。 Hereinafter, the fuel reformer according to the present invention and the reformer included in the fuel reformer according to the present invention will be described in more detail with reference to FIGS. The fuel reformer according to the present invention is not limited to the embodiment of the present invention shown in FIG. 7 without departing from the object and the spirit of the present invention. And the reformer with which the fuel reformer by this invention is provided is not limited to embodiment of this invention of FIGS. 1-3 in the range which does not deviate from the objective and main point of this invention.

図１は、本発明の実施の形態に係る燃料改質装置が備える改質器の１態様（改質器１００）を示す図である。本発明の実施の形態に係る燃料改質装置が備える改質器１００は、燃料及び空気の流れ方向の上流側から順に、窒素吸着剤含有層（Ａ）（１１）と、酸化触媒含有層（Ｂ１）（１２）と、改質触媒含有層（Ｂ２）（１３）とを配設する。図４は、運転時（燃料及び空気の供給時）及び停止時（燃料及び空気の供給停止時）における、本発明の燃料改質装置が備える改質器の１つの態様である改質器１００の温度変化を示す図であるが、図４を参照すると、運転時（燃料及び空気の供給時）は、燃料タンク又は蒸発器により気化した常温の燃料ガス及び空気が窒素吸着剤含有層（Ａ）に吹き付けられるため、窒素吸着剤含有層（Ａ）(の少なくとも前方)は常温に保たれ、空気中に含まれる窒素が窒素吸着剤含有層中の窒素吸着剤に吸着されることとなる。酸化触媒含有層(Ｂ１）は酸化反応（発熱反応）が進行して高温となり（ただし、酸化反応（発熱反応）があまり進行していない酸化触媒含有層の上流側は常温に近い温度）、改質触媒含有層は、改質反応（吸熱反応）により下流側になるにしたがって徐々に低温となる。 FIG. 1 is a diagram showing one mode of a reformer (reformer 100) provided in a fuel reformer according to an embodiment of the present invention. The reformer 100 provided in the fuel reformer according to the embodiment of the present invention includes a nitrogen adsorbent-containing layer (A) (11) and an oxidation catalyst-containing layer (in order from the upstream side in the flow direction of fuel and air. B1) (12) and the reforming catalyst-containing layer (B2) (13) are disposed. FIG. 4 shows a reformer 100 which is one embodiment of the reformer provided in the fuel reformer of the present invention during operation (when fuel and air are supplied) and when stopped (when supply of fuel and air is stopped). Referring to FIG. 4, during operation (when supplying fuel and air), normal temperature fuel gas and air vaporized by a fuel tank or an evaporator are converted into a nitrogen adsorbent-containing layer (A ), The nitrogen adsorbent-containing layer (A) (at least in front of it) is kept at room temperature, and nitrogen contained in the air is adsorbed by the nitrogen adsorbent in the nitrogen adsorbent-containing layer. The oxidation catalyst-containing layer (B1) undergoes an oxidation reaction (exothermic reaction) and becomes high temperature (however, the upstream side of the oxidation catalyst-containing layer where the oxidation reaction (exothermic reaction) does not proceed so much is a temperature close to normal temperature) The quality catalyst-containing layer gradually becomes lower in temperature as it goes downstream due to the reforming reaction (endothermic reaction).

運転停止後、すなわち、常温の燃料ガス及び空気の供給が停止すると、酸化触媒含有層中の余熱の熱伝導によって、窒素吸着剤含有層（Ａ）及び改質触媒含有層（Ｂ２）に熱が移動し、窒素吸着剤含有層（Ａ）が昇温して、窒素吸着剤に吸着していた窒素が脱離してその窒素が改質器内を掃気し、そして、改質触媒含有層（特に下流側）も昇温して高温となる。 After the operation is stopped, that is, when the supply of fuel gas and air at normal temperature is stopped, heat is transferred to the nitrogen adsorbent-containing layer (A) and the reforming catalyst-containing layer (B2) by the heat conduction of the residual heat in the oxidation catalyst-containing layer. The nitrogen adsorbent-containing layer (A) is heated, the nitrogen adsorbed on the nitrogen adsorbent is desorbed, the nitrogen is scavenged in the reformer, and the reforming catalyst-containing layer (particularly, The temperature on the downstream side also rises to a high temperature.

図２は、本発明の実施の形態に係る燃料改質装置が備える改質器の別の１態様（改質器２００）を示す図である。本発明の実施の形態に係る燃料改質装置が備える改質器２００は、燃料及び空気の流れ方向の上流側から順に、酸化触媒含有層（Ｂ１）（２１）と、改質触媒含有層（Ｂ２）（２２）と、窒素吸着剤含有層（Ａ）（２３）とを配設する。改質触媒含有層の下流側に窒素吸着剤含有層が配設されても、常温の燃料ガス及び空気の供給が停止すると、酸化触媒含有層中の余熱の熱伝導によって、窒素吸着剤含有層（Ａ）及び改質触媒含有層（Ｂ２）に熱が移動し、窒素吸着剤含有層（Ａ）が昇温して、窒素吸着剤に吸着していた窒素が脱離して、窒素が改質器内を掃気する。 FIG. 2 is a diagram showing another aspect (reformer 200) of the reformer provided in the fuel reformer according to the embodiment of the present invention. The reformer 200 provided in the fuel reformer according to the embodiment of the present invention includes an oxidation catalyst-containing layer (B1) (21) and a reforming catalyst-containing layer (21) in order from the upstream side in the fuel and air flow direction. B2) (22) and a nitrogen adsorbent-containing layer (A) (23) are disposed. Even if the nitrogen adsorbent-containing layer is disposed on the downstream side of the reforming catalyst-containing layer, if the supply of fuel gas and air at room temperature is stopped, the heat transfer of the residual heat in the oxidation catalyst-containing layer causes the nitrogen adsorbent-containing layer. Heat is transferred to (A) and the reforming catalyst-containing layer (B2), the temperature of the nitrogen adsorbent-containing layer (A) rises, and the nitrogen adsorbed on the nitrogen adsorbent is desorbed, and the nitrogen is reformed. Scavenge the vessel.

図３は、本発明の実施の形態に係る燃料改質装置が備える改質器の更に別の１態様（改質器３００）を示す図である。本発明の実施の形態に係る燃料改質装置が備える改質器３００は、燃料及び空気の流れ方向の上流側から順に、窒素吸着剤含有層（Ａ）（３１）と、酸化触媒含有層（Ｂ１）（３３）と、改質触媒含有層（Ｂ２）（３４）とが配設され、
窒素吸着剤含有層（Ａ）(３１)と、酸化触媒含有層（Ｂ１）(３３）との間に断熱性保持具（３２）が配設される。断熱性保持具（３２）は、断熱性を有する材料であれば任意の材料でよいが、例えば、セラミックファイバー等が挙げられる。運転中（燃料及び空気の供給中）は、改質器内（少なくとも窒素吸着剤含有層周辺）は高圧となって空気中に含まれる窒素が窒素吸着剤含有層（Ａ）（３１）中の窒素吸着剤に吸着されることとなる。そして、運転を停止（燃料及び空気の供給停止）すると、改質器内は圧力が低下するので、窒素吸着剤含有層（Ａ）（３１）中の窒素吸着剤に吸着していた窒素が脱離して改質器内を掃気することができる。このように窒素吸着剤含有層（Ａ）（３１）が酸化触媒含有層（Ｂ１）（３３）から断熱された状態で配設されてもよい。
FIG. 3 is a view showing still another aspect (reformer 300) of the reformer provided in the fuel reformer according to the embodiment of the present invention. The reformer 300 provided in the fuel reformer according to the embodiment of the present invention includes a nitrogen adsorbent-containing layer (A) (31) and an oxidation catalyst-containing layer (in order from the upstream side in the flow direction of fuel and air. B1) (33) and the reforming catalyst-containing layer (B2) (34) are disposed,
A heat insulating holder (32) is disposed between the nitrogen adsorbent-containing layer (A) (31) and the oxidation catalyst-containing layer (B1) (33). The heat insulating holder (32) may be any material as long as it has a heat insulating property, and examples thereof include ceramic fibers. During operation (fuel and air supply), the reformer (at least around the nitrogen adsorbent-containing layer) is at a high pressure, and nitrogen contained in the air is contained in the nitrogen adsorbent-containing layer (A) (31). It will be adsorbed by the nitrogen adsorbent. When the operation is stopped (fuel and air supply is stopped), the pressure in the reformer decreases, so that the nitrogen adsorbed on the nitrogen adsorbent in the nitrogen adsorbent-containing layer (A) (31) is removed. The reformer can be scavenged away. Thus, the nitrogen adsorbent-containing layer (A) (31) may be disposed in a state of being insulated from the oxidation catalyst-containing layer (B1) (33).

図５は、従来の燃料改質装置が備える改質器５００を示す図である。改質器５００は窒素吸着剤含有層を有していない。図６は、運転時（燃料及び空気の供給時）及び停止時（燃料及び空気の供給停止時）における、従来の燃料改質装置が備える改質器５００の温度変化を示す図である。 FIG. 5 is a diagram showing a reformer 500 provided in a conventional fuel reformer. The reformer 500 does not have a nitrogen adsorbent-containing layer. FIG. 6 is a diagram illustrating a temperature change of the reformer 500 included in the conventional fuel reformer during operation (when supplying fuel and air) and when stopped (when supply of fuel and air is stopped).

図７は、本発明の燃料改質装置のシステム構成図である。本発明の燃料改質装置のシステム構成図を参照すれば、理解されるとおり、本発明の燃料改質装置は燃料タンク、空気タンク、蒸発器、混合器、改質空気供給ライン及び改質器１００を備えるが、パージ空気供給ラインを備えていない。パージ用空気が不要であるためパージ空気供給ラインを備える必要がなく、これにより酸化触媒及び改質触媒の酸化による劣化を防止することができる。図示はされていないが、図７中の改質器１００を、改質器２００又は改質器３００に置き換えてもよい。すなわち、図７中の改質器１００を、改質器２００又は改質器３００に置き換えても改質１００を備える燃料改質装置と同様な燃料改質装置が得られ、パージ空気供給ラインが不要になる。 FIG. 7 is a system configuration diagram of the fuel reformer of the present invention. Referring to the system configuration diagram of the fuel reformer of the present invention, as will be understood, the fuel reformer of the present invention includes a fuel tank, an air tank, an evaporator, a mixer, a reformed air supply line, and a reformer. 100, but no purge air supply line. Since purge air is not required, it is not necessary to provide a purge air supply line, thereby preventing deterioration of the oxidation catalyst and reforming catalyst due to oxidation. Although not shown, the reformer 100 in FIG. 7 may be replaced with the reformer 200 or the reformer 300. That is, even if the reformer 100 in FIG. 7 is replaced with the reformer 200 or the reformer 300, a fuel reformer similar to the fuel reformer including the reformer 100 is obtained, and the purge air supply line is It becomes unnecessary.

図８は、従来の燃料改質装置のシステム構成図である。従来の燃料改質装置は、燃料タンク、空気タンク、蒸発器、混合器、改質空気供給ライン及び改質器５００を備えるのに加えて、パージ空気供給ラインを備えていることが理解できる。 FIG. 8 is a system configuration diagram of a conventional fuel reformer. It can be understood that the conventional fuel reformer includes a purge air supply line in addition to the fuel tank, the air tank, the evaporator, the mixer, the reformed air supply line, and the reformer 500.

（２）改質器内を掃気する方法
本発明による改質器内を掃気する方法は、本発明の燃料改質装置において、窒素吸着剤含有層（Ａ）から脱離された窒素を用いることを特徴とする。本発明による改質器内を掃気する方法は、運転時（燃料及び空気の供給時）よりも停止時（燃料及び空気の供給停止時）に高温になる箇所（改質触媒含有層の下流側又は酸化触媒含有層の上流側）等に窒素吸着剤含有層（Ａ）を設置して、運転時（燃料及び空気の供給時）に、窒素吸着剤含有層（Ａ）中の窒素吸着剤に窒素を吸着させ、停止後（燃料及び空気の供給停止後）に、窒素吸着剤含有層（Ａ）中の窒素吸着剤から窒素を脱離させ、その窒素で改質器内を掃気する方法である。改質内を掃気する際、パージ用空気が不要であるため、本発明の燃料改質装置にはパージ空気供給ラインを備える必要はない。 (2) Method of scavenging the interior of the reformer The method of scavenging the interior of the reformer according to the present invention uses nitrogen desorbed from the nitrogen adsorbent-containing layer (A) in the fuel reformer of the present invention. It is characterized by. The method of scavenging the inside of the reformer according to the present invention is a place where the temperature becomes higher at the time of stopping (when the supply of fuel and air is stopped) than at the time of operation (when supplying fuel and air) (downstream of the reforming catalyst-containing layer) Alternatively, the nitrogen adsorbent-containing layer (A) is installed on the upstream side of the oxidation catalyst-containing layer, etc., and the nitrogen adsorbent in the nitrogen adsorbent-containing layer (A) is operated during operation (when supplying fuel and air). After nitrogen is adsorbed and stopped (after stopping the supply of fuel and air), nitrogen is desorbed from the nitrogen adsorbent in the nitrogen adsorbent-containing layer (A), and the inside of the reformer is scavenged with the nitrogen. is there. When scavenging the interior of the reforming, no purge air is required, so the fuel reforming apparatus of the present invention does not need to be provided with a purge air supply line.

１１窒素吸着剤含有層（Ａ）
１２酸化触媒含有層（Ｂ１）
１３改質触媒含有層（Ｂ２）
２１酸化触媒含有層（Ｂ１）
２２改質触媒含有層（Ｂ２）
２３窒素吸着剤含有層（Ａ）
３１窒素吸着剤含有層（Ａ）
３２断熱性保持具
３３酸化触媒含有層（Ｂ１）
３４改質触媒含有層（Ｂ２）
５１酸化触媒含有層
５２改質触媒含有層
１００本発明の改質器
２００本発明の改質器
３００本発明の改質器
５００従来の改質器 11 Nitrogen adsorbent containing layer (A)
12 Oxidation catalyst-containing layer (B1)
13 Reforming catalyst-containing layer (B2)
21 Oxidation catalyst-containing layer (B1)
22 Reforming catalyst-containing layer (B2)
23 Nitrogen adsorbent containing layer (A)
31 Nitrogen adsorbent containing layer (A)
32 Insulating holder 33 Oxidation catalyst-containing layer (B1)
34 Reforming catalyst-containing layer (B2)
51 oxidation catalyst-containing layer 52 reforming catalyst-containing layer 100 reformer of the present invention 200 reformer of the present invention 300 reformer of the present invention 500 conventional reformer

Claims

A fuel reformer comprising a reformer including at least a nitrogen adsorbent-containing layer (A) and a catalyst-containing layer (B).

The fuel reformer according to claim 1, wherein the catalyst-containing layer (B) includes an oxidation catalyst-containing layer (B1) and a reforming catalyst-containing layer (B2).

The nitrogen adsorbent-containing layer (A), the oxidation catalyst-containing layer (B1), and the reforming catalyst-containing layer (B2) are disposed in order from the upstream side in the flow direction of fuel and air. Item 3. The fuel reformer according to Item 2.

The fuel reformer according to claim 3, wherein a heat insulating holder is disposed between the nitrogen adsorbent-containing layer (A) and the oxidation catalyst-containing layer (B1).

The fuel reformer according to any one of claims 1 to 4, wherein the nitrogen adsorbent-containing layer (A) is disposed on the most upstream side in the flow direction of fuel and air.

The oxidation catalyst-containing layer (B1), the reforming catalyst-containing layer (B2), and the nitrogen adsorbent-containing layer (A) are disposed in order from the upstream side in the flow direction of fuel and air. Item 3. The fuel reformer according to Item 2.

The fuel reformer according to claim 2 or 6, wherein the oxidation catalyst-containing layer (B1) is disposed on the most upstream side in the flow direction of fuel and air.

The method for scavenging the interior of the reformer using the nitrogen desorbed from the nitrogen adsorbent-containing layer (A) in the fuel reformer according to any one of claims 1 to 7.