JP3865167B2 - Fuel cell power generator with carbon dioxide recovery device - Google Patents

Fuel cell power generator with carbon dioxide recovery device Download PDF

Info

Publication number
JP3865167B2
JP3865167B2 JP30240597A JP30240597A JP3865167B2 JP 3865167 B2 JP3865167 B2 JP 3865167B2 JP 30240597 A JP30240597 A JP 30240597A JP 30240597 A JP30240597 A JP 30240597A JP 3865167 B2 JP3865167 B2 JP 3865167B2
Authority
JP
Japan
Prior art keywords
carbon dioxide
exhaust gas
gas
cathode
anode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP30240597A
Other languages
Japanese (ja)
Other versions
JPH11144750A (en
Inventor
意 武井
宏吉 上松
和典 小林
Original Assignee
石川島播磨重工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 石川島播磨重工業株式会社 filed Critical 石川島播磨重工業株式会社
Priority to JP30240597A priority Critical patent/JP3865167B2/en
Publication of JPH11144750A publication Critical patent/JPH11144750A/en
Application granted granted Critical
Publication of JP3865167B2 publication Critical patent/JP3865167B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/40—Capture or disposal of greenhouse gases of CO2
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Description

【０００１】
【発明の属する技術分野】
本発明は、アノード排ガスに含まれる炭酸ガスを回収する炭酸ガス回収装置付燃料電池発電装置に関する。
【０００２】
【従来の技術】
溶融炭酸塩型燃料電池は、高効率で環境への影響が少ないなど、従来の発電装置にない特徴を有しており、水力、火力、原子力に続く発電システムとして注目を集め、現在鋭意研究が進められている。
【０００３】
図２は都市ガスを燃料とする溶融炭酸塩型燃料電池を用いた発電設備の一例を示す図である。同図において、発電設備は、蒸気と混合した燃料ガス（都市ガス）を水素を含むアノードガスに改質する改質器２２と、酸素を含むカソードガスと水素を含むアノードガスとから発電する燃料電池２０とを備えており、改質器２２で作られるアノードガスはアノードガスライン２により燃料電池２０に供給され、燃料電池２０の中でその大部分を消費してアノード排ガスとなり、アノード排ガスライン４により燃焼用ガスとして燃焼器２３へ供給される。
【０００４】
燃焼器２３ではアノード排ガス中の可燃成分（水素、一酸化炭素、メタン等）を燃焼して高温の燃焼排ガスを生成し、改質器２２の加熱室に供給しこの燃焼排ガスにより改質室を加熱し、改質室で改質触媒により燃料ガスを改質してアノードガスとする。アノードガスは燃料予熱器２４によって燃料ガスライン１を流れる蒸気と混合した燃料ガスと熱交換し、燃料電池２０のアノードに供給される。また加熱室を出た燃焼排ガスは炭酸ガスリサイクルライン７で炭酸ガスリサイクルブロワ３２によりカソードに供給される。燃焼排ガスには多量の炭酸ガスが含まれており、電池反応に必要な炭酸ガスの供給源となる。空気ライン８からの空気が炭酸ガスリサイクルブロワ３２の出側に供給されカソードの電池反応に必要な酸素を供給する。カソードから排出されるカソード排ガスの一部は循環ライン３によりカソードに供給される。このカソード排ガスと燃焼排ガスと空気が混合してカソードガスとなりカソードに供給される。
【０００５】
このカソードガスは燃料電池２０内で電池反応して高温のカソード排ガスとなり、一部は循環ライン３によりカソードを循環し、他の一部はカソード排ガスライン５により燃焼器２３へ供給され、残部は排熱利用ライン６で空気を圧縮する圧縮機を駆動するタービン圧縮機２８で動力を回収した後、さらに排熱回収蒸気発生装置３０で熱エネルギを回収して系外に排出される。なお、この排熱回収蒸気発生装置３０で発生した蒸気が蒸気ライン９により燃料ガスライン１に入り、燃料ガスと混合して改質器２２に送られる。
【０００６】
【発明が解決しようとする課題】
アノード排ガス中にはドライベースで９０％程度の炭酸ガスが含まれている。この炭酸ガスは燃焼器２３、加熱室を通り炭酸ガスリサイクルブロワ３２によりカソードに供給され、電池反応に必要な炭酸ガスが消費される。しかし余剰の炭酸ガスはカソード排ガスとともにタービン圧縮機２８に供給され、タービンを駆動後、排熱回収蒸気発生装置３０で蒸気を発生した後、大気に放出される。従来からアノード排ガス中の炭酸ガスを回収するという考えはあったが、燃焼器２３へ供給されるアノード排ガスライン４に炭酸ガス回収装置を設けると、アノード排ガスの流量は大幅に減少する。これは炭酸ガス回収装置は通常アノード排ガスを冷却して水分を凝縮し炭酸ガスを回収するためアノード排ガスに約５０％（ウェット）の存在する水分がほとんど凝縮するためである。この流量減少と温度低下により、電池での燃料利用率とプラント効率は低下する。また炭酸ガス回収両が過大な時は電池反応に必要な炭酸ガスが不足するという問題がある。炭酸ガスの大気放出削減はプラントの存続にかかわる重要な問題であり、発電量当たりの炭酸ガス排出量の低減が強く要望されている。
【０００７】
本発明は上述の問題に鑑みてなされたもので、アノード排ガス中の炭酸ガスについて、電池反応に必要な炭酸ガスを除く残りの炭酸ガスを回収する炭酸ガス回収装置付燃料電池発電装置を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記目的を達成するため、請求項１の発明では、カソードとアノードからなり酸素を含むカソードガスと水素を含むアノードガスから発電する燃料電池と、カソードから排出されるカソード排ガスの一部とアノードから排出されるアノード排ガスの一部とを燃焼する第１燃焼器と、この第１燃焼器の燃焼排ガスで水蒸気を含む燃料ガスを改質する改質器と、この改質器の燃焼排ガスをカソードに循環させる炭酸ガスリサイクルラインと、カソード排ガスの一部に前記炭酸ガスリサイクルラインの燃焼排ガスと空気とを混合してカソードを循環させる循環ラインと、前記アノード排ガスの残部より炭酸ガスを回収する炭酸ガス回収装置と、この炭酸ガス回収装置からの排ガスと前記カソード排ガスの残部とを燃焼する第２燃焼器と、この第２燃焼器の燃焼排ガスでタービンを回転して空気圧縮機を駆動し前記循環ラインに空気を供給するタービン圧縮機と、を備える。
【０００９】
アノード排ガスから改質器の加熱およびカソードが必要とする炭酸ガス量に対応するアノード排ガス量を第１燃焼器に分岐し、残部を炭酸ガス回収装置に供給する。炭酸ガス回収装置では加圧・冷却により炭酸ガスを液化して取り出す等によりアノード排ガス中より炭酸ガスを除去する。この炭酸ガス回収装置からの排ガスとカソード排ガスの残部とを第２燃焼器で燃焼し、この燃焼ガスでタービン圧縮機のタービンを駆動した後、タービン排ガスを最終的には大気放出する。第２燃焼器には炭酸ガスをかなりの割合で除去したカソード排ガスが供給されるので、燃焼ガスに含まれる炭酸ガスは従来に比べ大幅に減少している。
【００１０】
【発明の実施の形態】
以下、本発明の実施形態について図面を参照して説明する。
図１は本発明の実施形態の燃料電池発電装置の全体構成図である。本図において図２と同一機能を有するものは同一符号で表す。燃料電池発電装置は、蒸気を含む燃料ガスを加熱する燃料予熱器２４と、この加熱された燃料ガスを水素を含むアノードガスに改質する改質器２２と、このアノードガスと酸素および炭酸ガスを含むカソードガスとから発電する燃料電池２０とを備える。燃料電池２０から排出されるアノード排ガスの一部は、アノード排ガスライン４により第１燃焼器２３に供給され、酸素を含むカソード排ガスの一部と共に燃焼触媒を用いて燃焼する。改質器２２は加熱室と改質室からなり、加熱室には第１燃焼器２３からの燃焼排ガスが供給され、改質室は水蒸気を含む都市ガスを改質触媒と加熱室からの加熱により水素を含むアノードガスに改質し、アノードガスライン２によりアノードに供給する。加熱室より排出される燃焼排ガスには炭酸ガスが含まれるので、この炭酸ガスを炭酸ガスリサイクルライン７により循環ライン３に供給する。循環ライン３はこの炭酸ガスと空気ライン８により供給される酸素とカソード排ガスの一部とを混合してカソードガスとし、炭酸ガスリサイクルブロワ３２によりカソードを循環させる。循環ライン３の循環ガス量は流量制御弁４２により調整される。
【００１１】
天然ガスを成分とする都市ガスは燃料ガスライン１により供給され、脱硫器２６で硫酸分を除去された後蒸気ライン９からの蒸気と混合し、燃料予熱器２４で加熱されて改質器２２に入りアノードガスに改質されて、アノードガスライン２により燃料電池２０のアノードに供給される。燃料電池２０のカソードには、炭酸ガスリサイクルライン７からの炭酸ガスと、空気ライン８からの空気と、循環ライン３からのカソード排ガスとが混合されてカソードガスとなり、炭酸ガスリサイクルブロワ３２により供給される。燃料電池２０はアノードガスとカソードガスを供給され発電を行う。アノードでの反応により蒸気と未燃焼成分を含むアノード排ガスが排出され、アノード排ガスライン４により一部は第１燃焼器２３に供給され、残部は炭酸ガス回収装置４０に供給される。燃焼器２３と炭酸ガス回収装置４０へのラインを分けることにより、燃焼器２３の燃料の流量減少、温度低下を防ぐことができ、電池の燃料利用率低下をひき起こさない。カソードでの反応により生成さたカソード排ガスは、一部は循環ライン３によりカソードへ循環し、他の一部はカソード排ガスライン５により第１燃焼器２３に供給され、残部は第２燃焼器４１に供給される。
【００１２】
第１燃焼器２３には燃料電池２０のアノード排ガスの一部とカソード排ガスの一部が供給される。燃料電池２０の燃料利用率は８０％程度なので、アノード排ガスには２０％程度の燃料成分が含まれている。カソード排ガスには燃焼に必要な酸素が含まれている。これらが第１燃焼器２３で燃焼され高温の燃焼排ガスを生成しこれを改質器２２に供給する。改質器２２で燃料ガスを加熱した後の燃焼排ガスには炭酸ガスが含まれ、これはカソードでの電池反応に必要なので、炭酸ガスリサイクルライン７によりカソードへ供給される。
【００１３】
炭酸ガス回収装置４０はアノード排ガス中に含まれる炭酸ガスを分離して取り出す装置で、幾つかの方式があるが、一例として加圧・冷却し液化して取り出す方法がある。本実施形態ではアノード排ガスを３ＭＰａ程度に加圧し、−４０℃程度に冷却して炭酸ガスを液化して分離して取り出す。なお、冷却にはＬＮＧ（液化天然ガス）の気化の際の冷熱などを用いることにより低コストで冷却を行うことができる。また炭酸ガス回収量が過大になると電池反応に必要な炭酸ガスが不足するという制約もない。
【００１４】
炭酸ガス回収装置４０で炭酸ガスを除去されたアノード排ガスとカソード排ガスは第２燃焼器４１で燃焼して燃焼ガスとなり、タービン圧縮機２８のタービンを駆動した後、排熱回収蒸気発生装置３０へ供給される。排熱回収蒸気発生装置３０では給水をタービン圧縮機２８のタービンを駆動した排ガスにより蒸気とし、蒸気ライン９により燃料ガスライン１に供給する。排熱回収蒸気発生装置３０の排ガスは大気に放出されるが、炭酸ガスは従来に比べ大幅に低減している。
【００１５】
空気はタービン圧縮機２８の圧縮機へ入り、加圧されて空気ライン８に供給される。
【００１６】
【発明の効果】
以上の説明より明らかなように、本発明は、改質器の加熱や電池反応に必要な炭酸ガスを含むアノード排ガスを除いたアノード排ガスより炭酸ガスを回収し、この炭酸ガスを除いた排ガスとカソード排ガスとを燃焼して、この燃焼ガスのエネルギを回収した後、大気に放出する。これによりプラント発電効率をあまり低下させずに大気に放出される炭酸ガスを大幅に低減することができる。
【図面の簡単な説明】
【図１】本発明の実施形態の燃料電池発電装置の全体構成図である。
【図２】従来の燃料電池発電装置の全体構成図である。
【符号の説明】
１ 燃料ガスライン
２ アノードガスライン
３ 循環ライン
４ アノード排ガスライン
５ カソード排ガスライン
６ 排熱利用ライン
７ 炭酸ガスリサイクルライン
８ 空気ライン
９ 蒸気ライン
２０ 燃料電池
２２ 改質器
２３ 第１燃焼器
２４ 燃料予熱器
２６ 脱硫器
２８ タービン圧縮機
３０ 排熱回収蒸気発生装置
３２ 炭酸ガスリサイクルブロワ
４０ 炭酸ガス回収装置
４１ 第２燃焼器
４２ 流量制御弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel cell power generator with a carbon dioxide recovery device that recovers carbon dioxide contained in anode exhaust gas.
[0002]
[Prior art]
Molten carbonate fuel cells have features that are not found in conventional power generators, such as high efficiency and little impact on the environment. They attract attention as a power generation system that follows hydropower, thermal power, and nuclear power, and are currently under intense research. It is being advanced.
[0003]
FIG. 2 is a diagram showing an example of power generation equipment using a molten carbonate fuel cell using city gas as fuel. In the figure, the power generation facility is a fuel that generates power from a reformer 22 that reforms a fuel gas (city gas) mixed with steam into an anode gas containing hydrogen, a cathode gas containing oxygen, and an anode gas containing hydrogen. The anode gas produced by the reformer 22 is supplied to the fuel cell 20 through the anode gas line 2 and consumes most of the fuel cell 20 to become anode exhaust gas. 4 is supplied to the combustor 23 as a combustion gas.
[0004]
In the combustor 23, combustible components (hydrogen, carbon monoxide, methane, etc.) in the anode exhaust gas are combusted to generate high-temperature combustion exhaust gas, which is supplied to the heating chamber of the reformer 22, and the reforming chamber is formed by this combustion exhaust gas. The fuel gas is heated and reformed with a reforming catalyst in the reforming chamber to form anode gas. The anode gas exchanges heat with the fuel gas mixed with the vapor flowing through the fuel gas line 1 by the fuel preheater 24 and is supplied to the anode of the fuel cell 20. The combustion exhaust gas that has left the heating chamber is supplied to the cathode by the carbon dioxide recycling blower 32 in the carbon dioxide recycling line 7. The combustion exhaust gas contains a large amount of carbon dioxide, and becomes a supply source of carbon dioxide necessary for the battery reaction. Air from the air line 8 is supplied to the outlet side of the carbon dioxide recycle blower 32 to supply oxygen necessary for the cell reaction of the cathode. A part of the cathode exhaust gas discharged from the cathode is supplied to the cathode through the circulation line 3. The cathode exhaust gas, combustion exhaust gas, and air are mixed to form cathode gas and supplied to the cathode.
[0005]
This cathode gas reacts in the fuel cell 20 to become high-temperature cathode exhaust gas, part of which circulates through the cathode through the circulation line 3, the other part is supplied to the combustor 23 through the cathode exhaust gas line 5, and the rest After the power is recovered by the turbine compressor 28 that drives the compressor that compresses the air in the exhaust heat utilization line 6, the heat energy is recovered by the exhaust heat recovery steam generator 30 and discharged outside the system. The steam generated by the exhaust heat recovery steam generator 30 enters the fuel gas line 1 through the steam line 9, mixes with the fuel gas, and is sent to the reformer 22.
[0006]
[Problems to be solved by the invention]
The anode exhaust gas contains about 90% carbon dioxide on a dry basis. The carbon dioxide gas passes through the combustor 23 and the heating chamber, and is supplied to the cathode by the carbon dioxide gas recycle blower 32, so that the carbon dioxide gas necessary for the cell reaction is consumed. However, surplus carbon dioxide gas is supplied to the turbine compressor 28 together with the cathode exhaust gas, and after the turbine is driven, steam is generated by the exhaust heat recovery steam generator 30 and then released to the atmosphere. Conventionally, there has been an idea of recovering carbon dioxide gas in the anode exhaust gas. However, if a carbon dioxide gas recovery device is provided in the anode exhaust gas line 4 supplied to the combustor 23, the flow rate of the anode exhaust gas is greatly reduced. This is because the carbon dioxide recovery device normally cools the anode exhaust gas to condense moisture and recover the carbon dioxide gas, so that about 50% (wet) of moisture is almost condensed in the anode exhaust gas. Due to the decrease in flow rate and temperature, the fuel utilization rate and plant efficiency in the battery are reduced. Further, when both of the carbon dioxide recoveries are excessive, there is a problem that the carbon dioxide necessary for the battery reaction is insufficient. Reduction of carbon dioxide emission to the atmosphere is an important issue related to the continuation of the plant, and there is a strong demand for reduction of carbon dioxide emission per unit of power generation.
[0007]
The present invention has been made in view of the above problems, and provides a fuel cell power generator with a carbon dioxide recovery device that recovers the remaining carbon dioxide excluding the carbon dioxide necessary for battery reaction with respect to carbon dioxide in the anode exhaust gas. For the purpose.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, a fuel cell comprising a cathode and an anode and generating electricity from a cathode gas containing oxygen and an anode gas containing hydrogen, a part of cathode exhaust gas discharged from the cathode, and the anode are used. A first combustor that combusts a part of the discharged anode exhaust gas, a reformer that reforms fuel gas containing water vapor with the combustion exhaust gas of the first combustor, and the combustion exhaust gas of the reformer as a cathode A carbon dioxide gas recycling line to be circulated, a circulation line to circulate the cathode by mixing a part of the cathode exhaust gas with the combustion exhaust gas and air of the carbon dioxide gas recycling line, and a carbon dioxide gas to recover carbon dioxide gas from the remainder of the anode exhaust gas. A gas recovery device, a second combustor for combusting the exhaust gas from the carbon dioxide recovery device and the remainder of the cathode exhaust gas, and the second fuel By rotating the turbine at a vessel of the combustion exhaust gas to drive the air compressor and a turbine compressor for supplying air to the circulation line.
[0009]
From the anode exhaust gas, the amount of anode exhaust gas corresponding to the heating of the reformer and the amount of carbon dioxide required by the cathode is branched to the first combustor, and the remainder is supplied to the carbon dioxide recovery device. In the carbon dioxide gas recovery device, carbon dioxide gas is removed from the anode exhaust gas by liquefying and taking out the carbon dioxide gas by pressurization and cooling. The exhaust gas from the carbon dioxide recovery device and the remainder of the cathode exhaust gas are combusted by the second combustor, and the turbine of the turbine compressor is driven by this combustion gas, and then the turbine exhaust gas is finally released into the atmosphere. The second combustor is supplied with cathode exhaust gas from which carbon dioxide gas has been removed in a considerable proportion, so that the carbon dioxide contained in the combustion gas is greatly reduced as compared with the prior art.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall configuration diagram of a fuel cell power generator according to an embodiment of the present invention. In this figure, those having the same functions as those in FIG. The fuel cell power generator includes a fuel preheater 24 that heats a fuel gas containing steam, a reformer 22 that reforms the heated fuel gas into an anode gas containing hydrogen, and the anode gas, oxygen, and carbon dioxide gas. A fuel cell 20 that generates electric power from a cathode gas containing A part of the anode exhaust gas discharged from the fuel cell 20 is supplied to the first combustor 23 by the anode exhaust gas line 4 and combusts using a combustion catalyst together with a part of the cathode exhaust gas containing oxygen. The reformer 22 includes a heating chamber and a reforming chamber. The combustion chamber is supplied with combustion exhaust gas from the first combustor 23, and the reforming chamber heats city gas containing water vapor from the reforming catalyst and the heating chamber. The anode gas containing hydrogen is reformed and supplied to the anode through the anode gas line 2. Since the combustion exhaust gas discharged from the heating chamber contains carbon dioxide, this carbon dioxide is supplied to the circulation line 3 through the carbon dioxide recycling line 7. The circulation line 3 mixes the carbon dioxide gas, oxygen supplied from the air line 8 and a part of the cathode exhaust gas to form a cathode gas, and circulates the cathode by the carbon dioxide gas recycle blower 32. The amount of circulating gas in the circulation line 3 is adjusted by the flow control valve 42.
[0011]
The city gas containing natural gas is supplied from the fuel gas line 1, and after the sulfuric acid content is removed by the desulfurizer 26, it is mixed with the steam from the steam line 9, heated by the fuel preheater 24, and reformer 22. The anode gas is reformed and supplied to the anode of the fuel cell 20 through the anode gas line 2. The cathode of the fuel cell 20 is mixed with carbon dioxide from the carbon dioxide recycling line 7, air from the air line 8, and cathode exhaust gas from the circulation line 3 to form cathode gas, which is supplied by the carbon dioxide recycling blower 32. Is done. The fuel cell 20 is supplied with anode gas and cathode gas to generate power. Anode exhaust gas containing steam and unburned components is discharged by the reaction at the anode, a part of the anode exhaust gas line 4 is supplied to the first combustor 23, and the remaining part is supplied to the carbon dioxide gas recovery device 40. By separating the line to the combustor 23 and the carbon dioxide gas recovery device 40, it is possible to prevent a decrease in the fuel flow rate and temperature in the combustor 23 and not to cause a decrease in the fuel utilization rate of the battery. A part of the cathode exhaust gas generated by the reaction at the cathode is circulated to the cathode by the circulation line 3, the other part is supplied to the first combustor 23 by the cathode exhaust gas line 5, and the rest is the second combustor 41. To be supplied.
[0012]
The first combustor 23 is supplied with part of the anode exhaust gas of the fuel cell 20 and part of the cathode exhaust gas. Since the fuel utilization rate of the fuel cell 20 is about 80%, the anode exhaust gas contains about 20% of the fuel component. The cathode exhaust gas contains oxygen necessary for combustion. These are combusted in the first combustor 23 to generate high-temperature combustion exhaust gas, which is supplied to the reformer 22. The combustion exhaust gas after heating the fuel gas by the reformer 22 contains carbon dioxide gas, which is necessary for the cell reaction at the cathode, and is supplied to the cathode by the carbon dioxide gas recycling line 7.
[0013]
The carbon dioxide recovery device 40 is a device that separates and extracts the carbon dioxide contained in the anode exhaust gas, and there are several methods. As an example, there is a method of pressurizing and cooling to liquefy and take out. In this embodiment, the anode exhaust gas is pressurized to about 3 MPa, cooled to about −40 ° C., and the carbon dioxide gas is liquefied and separated and taken out. In addition, it can cool at low cost by using the cold heat | fever at the time of vaporization of LNG (liquefied natural gas), etc. for cooling. Moreover, there is no restriction that the carbon dioxide required for the battery reaction is insufficient when the amount of recovered carbon dioxide is excessive.
[0014]
The anode exhaust gas and cathode exhaust gas from which the carbon dioxide gas has been removed by the carbon dioxide recovery device 40 are burned by the second combustor 41 to become combustion gas, and after driving the turbine of the turbine compressor 28, to the exhaust heat recovery steam generator 30. Supplied. In the exhaust heat recovery steam generator 30, the feed water is converted into steam by the exhaust gas that has driven the turbine of the turbine compressor 28, and is supplied to the fuel gas line 1 through the steam line 9. The exhaust gas of the exhaust heat recovery steam generator 30 is released to the atmosphere, but the carbon dioxide gas is greatly reduced compared to the conventional case.
[0015]
Air enters the compressor of the turbine compressor 28, is pressurized and supplied to the air line 8.
[0016]
【The invention's effect】
As is clear from the above description, the present invention recovers carbon dioxide gas from the anode exhaust gas excluding the anode exhaust gas containing carbon dioxide necessary for heating the reformer and the battery reaction, and the exhaust gas from which the carbon dioxide gas is removed. After the cathode exhaust gas is combusted and the energy of the combustion gas is recovered, it is released to the atmosphere. Thereby, the carbon dioxide gas discharged | emitted by air | atmosphere can be reduced significantly, without reducing plant power generation efficiency very much.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a fuel cell power generator according to an embodiment of the present invention.
FIG. 2 is an overall configuration diagram of a conventional fuel cell power generator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fuel gas line 2 Anode gas line 3 Circulation line 4 Anode exhaust gas line 5 Cathode exhaust gas line 6 Waste heat utilization line 7 Carbon dioxide gas recycling line 8 Air line 9 Steam line 20 Fuel cell 22 Reformer 23 First combustor 24 Fuel preheating 26 Desulfurizer 28 Turbine compressor 30 Waste heat recovery steam generator 32 Carbon dioxide recycle blower 40 Carbon dioxide recovery device 41 Second combustor 42 Flow control valve

Claims (1)

カソードとアノードからなり酸素を含むカソードガスと水素を含むアノードガスから発電する燃料電池と、カソードから排出されるカソード排ガスの一部とアノードから排出されるアノード排ガスの一部とを燃焼する第１燃焼器と、この第１燃焼器の燃焼排ガスで水蒸気を含む燃料ガスを改質する改質器と、この改質器の燃焼排ガスをカソードに循環させる炭酸ガスリサイクルラインと、カソード排ガスの一部に前記炭酸ガスリサイクルラインの燃焼排ガスと空気とを混合してカソードを循環させる循環ラインと、前記アノード排ガスの残部より炭酸ガスを回収する炭酸ガス回収装置と、この炭酸ガス回収装置からの排ガスと前記カソード排ガスの残部とを燃焼する第２燃焼器と、この第２燃焼器の燃焼排ガスでタービンを回転して空気圧縮機を駆動し前記循環ラインに空気を供給するタービン圧縮機と、を備えたことを特徴とする炭酸ガス回収装置付燃料電池発電装置。A fuel cell comprising a cathode and an anode and generating electricity from a cathode gas containing oxygen and an anode gas containing hydrogen, and a first part for burning a part of the cathode exhaust gas discharged from the cathode and a part of the anode exhaust gas discharged from the anode A combustor, a reformer for reforming fuel gas containing water vapor from the combustion exhaust gas of the first combustor, a carbon dioxide recycling line for circulating the combustion exhaust gas of the reformer to the cathode, and a part of the cathode exhaust gas A circulation line for mixing the combustion exhaust gas and air of the carbon dioxide recycling line to circulate the cathode, a carbon dioxide recovery device for recovering carbon dioxide from the remainder of the anode exhaust gas, and an exhaust gas from the carbon dioxide recovery device A second combustor that burns the remainder of the cathode exhaust gas, and a turbine that rotates with the combustion exhaust gas of the second combustor to compress the air Fuel cell power plant with a carbon dioxide recovery apparatus is characterized in that and a turbine compressor for supplying air to drive the circulation line.
JP30240597A 1997-11-05 1997-11-05 Fuel cell power generator with carbon dioxide recovery device Expired - Fee Related JP3865167B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP30240597A JP3865167B2 (en) 1997-11-05 1997-11-05 Fuel cell power generator with carbon dioxide recovery device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP30240597A JP3865167B2 (en) 1997-11-05 1997-11-05 Fuel cell power generator with carbon dioxide recovery device

Publications (2)

Publication Number Publication Date
JPH11144750A JPH11144750A (en) 1999-05-28
JP3865167B2 true JP3865167B2 (en) 2007-01-10

Family

ID=17908529

Family Applications (1)

Application Number Title Priority Date Filing Date
JP30240597A Expired - Fee Related JP3865167B2 (en) 1997-11-05 1997-11-05 Fuel cell power generator with carbon dioxide recovery device

Country Status (1)

Country Link
JP (1) JP3865167B2 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4042823B1 (en) * 2007-03-06 2008-02-06 有限会社新科学開発研究所 Circulating internal pressure engine and power generation system
CN105209377B (en) * 2013-03-15 2017-04-26 埃克森美孚研究工程公司 Integration of molten carbonate fuel cells in fischer-tropsch synthesis
CN115084602B (en) * 2022-08-23 2022-11-15 深圳市南科动力科技有限公司 Hydrogen emission treatment system and fuel cell

Also Published As

Publication number Publication date
JPH11144750A (en) 1999-05-28

Similar Documents

Publication Publication Date Title
KR100907690B1 (en) Combined Cycle Power Plant
US4041210A (en) Pressurized high temperature fuel cell power plant with bottoming cycle
KR20090108123A (en) Integrated fuel cell and heat engine hybrid system for high efficiency power generation
JPH11297336A (en) Composite power generating system
JP4154680B2 (en) Fuel cell power generator that injects steam into the anode exhaust gas line
JP3865167B2 (en) Fuel cell power generator with carbon dioxide recovery device
JPH10302819A (en) Fuel cell generating set
JP3564812B2 (en) Fuel cell power generation equipment
JPH04342961A (en) Fuel cell power generating facility
JP3072630B2 (en) Fuel cell combined cycle generator
JPH11126628A (en) Fuel cell power generating device fitted with carbon deposition preventing device
JPH1167251A (en) Fuel cell power generating device
JP3573239B2 (en) Fuel cell power generator
JP2004316535A (en) Cogeneration system
JPH0358154B2 (en)
JP2000228208A (en) Composite apparatus of fuel cell and gas turbine
JP4212322B2 (en) Combined power generation facilities for fuel cells and micro gas turbines and their startup methods
JP4218055B2 (en) Fuel cell power generator
JPH1167252A (en) Fuel cell power generating device
JP3263936B2 (en) Fuel cell generator
JP3582133B2 (en) Molten carbonate fuel cell power generator
JPH11162488A (en) Fuel cell power generating system injecting steam into cathode
JP3741288B2 (en) Method and apparatus for controlling cathode temperature of molten carbonate fuel cell power generation facility
JPH11354143A (en) Fuel cell power generating set with anode circulation line
JP3271677B2 (en) Fuel cell generator

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20040628

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20060531

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20060915

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20060928

S533 Written request for registration of change of name

Free format text: JAPANESE INTERMEDIATE CODE: R313533

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20091013

Year of fee payment: 3

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

LAPS Cancellation because of no payment of annual fees