# US 9,437,891 B2 · Hydrogen generator and fuel cell system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,437,891 B2 - Document ID: US9437891B2 - Status: Granted - Kind: B2 - Application number: 14/389,952 - Filed: 2013-04-19 - Published: 2015-03-12 - Granted: 2016-09-06 - Earliest claimed: 2012-04-19 - Assignees: Panasonic Intellectual Property Management Co., Ltd. - Applicants: Panasonic Intellectual Property Management Co., Ltd. - Inventors: Akihisa Yoshimura; Koichi Kusumura; Hirofumi Kokubu; Yoshio Tamura - Web page: https://patentgrep.com/patent/US9437891B2 ## CPC - H01M 8/0675: {Removal of sulfur} - C01B 3/32: by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide or air - C01B 3/38: using catalysts - H01M 8/04156: {with product water removal} - H01M 8/0618: {Reforming processes, e.g. autothermal, partial oxidation or steam reforming} - B01J 2219/24: Stationary reactors without moving elements inside - C01B 2203/0205: containing a reforming step - C01B 2203/0244: the reforming step being an autothermal reforming step, e.g. secondary reforming processes - C01B 2203/025: containing a partial oxidation step - C01B 2203/0283: containing a CO-shift step, i.e. a water gas shift step - C01B 2203/044: Selective oxidation of carbon monoxide - C01B 2203/0445: Selective methanation - C01B 2203/047: the impurity being carbon monoxide - C01B 2203/127: Catalytic desulfurisation - C01B 2203/148: involving a recycle stream to the feed of the process for making hydrogen or synthesis gas - Y02E 60/50: Fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A hydrogen generator comprises a reformer configured to generate a hydrogen-containing gas through a reforming reaction using a raw material; a hydrodesulfurization unit configured to remove a sulfur compound from the raw material; a recycle passage configured to flow therethrough the hydrogen-containing gas to be added to the raw material in a state before the raw material flows into the hydrodesulfurization unit, the recycle passage having a downward slope; and a water drain passage configured to discharge condensed water generated in the downward slope of the recycle passage. ## Claims ### Claim 1 A hydrogen generator comprising: a reformer configured to generate a hydrogen-containing gas through a reforming reaction using a raw material; a hydrogen-containing gas passage downstream of the reformer; a hydrodesulfurization unit configured to remove a sulfur compound from the raw material; a recycle passage configured to flow therethrough the hydrogen-containing gas to be added to the raw material in a state before the raw material flows into the hydrodesulfurization unit, the recycle passage having a downward slope such that at least a portion of the recycle passage is inclined with respect to the hydrogen-containing gas passage; and a water drain passage configured to discharge condensed water generated in the downward slope of the recycle passage. ### Claim 2 (depends on 1) The hydrogen generator according to claim 1, wherein the downward slope of the recycle passage includes a first passage sloping downward, and a second passage which is connected to the first passage and inclined at an obtuse angle with respect to the first passage; wherein the first passage and the second passage are configured such that the hydrogen-containing gas flows therethrough in this order; and wherein the first passage is inclined with respect to a horizontal plane at a greater angle than the second passage. ### Claim 3 (depends on 1) The hydrogen generator according to claim 1, wherein the recycle passage includes the downward slope and an upward slope in this order from an upstream side, and is joined to a raw material supply passage through which the raw material is supplied to the hydrodesulfurization unit, in a position which is downstream of the upward slope. ### Claim 4 (depends on 3) The hydrogen generator according to claim 3, wherein the upward slope of the recycle passage includes a third passage which is connected to the second passage and inclined at an obtuse angle with respect to the second passage, and a fourth passage which is connected to the third passage, is inclined at an obtuse angle with respect to the third passage, and slopes upward. ### Claim 5 (depends on 4) The hydrogen generator according to claim 4, wherein the water drain passage branches from the recycle passage at a location of a connecting portion of the second passage and of the third passage. ### Claim 6 (depends on 1) The hydrogen generator according to claim 1, wherein a downstream end of the water drain passage is sealed by water. ### Claim 7 (depends on 1) A fuel cell system comprising: the hydrogen generator as recited in claim 1; and a fuel cell configured to generate electric power using the hydrogen-containing gas supplied from the hydrogen generator. ### Claim 8 (depends on 7) The fuel cell system according to claim 7, comprising: a water tank configured to store water generated from an exhaust gas discharged from the fuel cell system; wherein the water drain passage is connected to the water tank at a location below a water level of the water tank. ### Claim 9 (depends on 8) The fuel cell system according to claim 8, comprising: an on-off valve provided in the recycle passage; and a control unit configured to open the on-off valve after filling of water into the water tank is performed such that the water level of the water tank becomes above the location of a connecting portion of the water drain passage and of the water tank. ### Claim 10 (depends on 1) The hydrogen generator according to claim 1, comprising: a casing configured to accommodate the reformer; wherein at least a part of the downward slope is cooled by a ventilation air flow for ventilating an interior of the casing. ### Claim 11 (depends on 3) The hydrogen generator according to claim 3, comprising: a casing configured to accommodate the reformer; wherein at least a part of the upward slope is cooled by a ventilation air flow for ventilating an interior of the casing.