Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0207—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly horizontal
  • B01J8/0214—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly horizontal in a cylindrical annular shaped bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0278—Feeding reactive fluids
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0285—Heating or cooling the reactor
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
  • C01B3/32—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
  • C01B3/34—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents
  • C01B3/38—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts
  • C01B3/382—Multi-step processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00026—Controlling or regulating the heat exchange system
  • B01J2208/00035—Controlling or regulating the heat exchange system involving measured parameters
  • B01J2208/00044—Temperature measurement
  • B01J2208/00061—Temperature measurement of the reactants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00106—Controlling the temperature by indirect heat exchange
  • B01J2208/00309—Controlling the temperature by indirect heat exchange with two or more reactions in heat exchange with each other, such as an endothermic reaction in heat exchange with an exothermic reaction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00548—Flow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00191—Control algorithm
  • B01J2219/00193—Sensing a parameter
  • B01J2219/00195—Sensing a parameter of the reaction system
  • B01J2219/002—Sensing a parameter of the reaction system inside the reactor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00191—Control algorithm
  • B01J2219/00211—Control algorithm comparing a sensed parameter with a pre-set value
  • B01J2219/00218—Dynamically variable (in-line) parameter values
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00191—Control algorithm
  • B01J2219/00222—Control algorithm taking actions
  • B01J2219/00227—Control algorithm taking actions modifying the operating conditions
  • B01J2219/00229—Control algorithm taking actions modifying the operating conditions of the reaction system
  • B01J2219/00231—Control algorithm taking actions modifying the operating conditions of the reaction system at the reactor inlet
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/02—Processes for making hydrogen or synthesis gas
  • C01B2203/0205—Processes for making hydrogen or synthesis gas containing a reforming step
  • C01B2203/0227—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step
  • C01B2203/0244—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/08—Methods of heating or cooling
  • C01B2203/0805—Methods of heating the process for making hydrogen or synthesis gas
  • C01B2203/0838—Methods of heating the process for making hydrogen or synthesis gas by heat exchange with exothermic reactions, other than by combustion of fuel
  • C01B2203/0844—Methods of heating the process for making hydrogen or synthesis gas by heat exchange with exothermic reactions, other than by combustion of fuel the non-combustive exothermic reaction being another reforming reaction as defined in groups C01B2203/02 - C01B2203/0294
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/14—Details of the flowsheet
  • C01B2203/142—At least two reforming, decomposition or partial oxidation steps in series
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/80—Aspect of integrated processes for the production of hydrogen or synthesis gas not covered by groups C01B2203/02 - C01B2203/1695
  • C01B2203/82—Several process steps of C01B2203/02 - C01B2203/08 integrated into a single apparatus

Definitions

• the invention relates to a method for adjusting the temperature profile of a catalyst in a reformer
• the reformer having an oxidation zone and a catalyst equipped reforming zone in thermal contact with the oxidation zone
• the reformer has a first media feed area and a second media feed area
• the oxidation zone has a first oxidation zone end region which faces the first media supply region and faces away from the second media supply region, and has a second oxidation zone end region facing the second media supply region and facing away from the first media supply region,
• the reforming zone has a first reforming zone end region which faces the first media supply region and faces away from the second media supply region and has a second reforming zone end region facing the second media supply region and facing away from the first media supply region,
• the method comprising the steps of Supplying fuel and air into the first media feed area to produce a fuel-air mixture
• the invention further relates to a system for reforming fuel. - -
• Such a method and such a system are known from DE 103 59 205 Al. They are used in fuel cell systems that run on hydrocarbons such as natural gas, gasoline or diesel.
• the reformer generates from the supplied hydrocarbon and air a mixture which is converted in the reformer to a hydrogen-rich reformate. This reformate is fed to the anode side of a fuel cell or a fuel cell stack.
• a temperature profile is formed within the catalyst through which the reacting gases flow, which generally has a much higher level at the catalyst inlet than at the catalyst outlet. This is because at the beginning of the catalyst strongly exothermic oxidation reactions take place, while in the rear catalyst section the actual endothermic reforming takes place.
• the invention has the object of developing the generic method and systems to the effect that in the catalyst or the reforming zone of a two-stage reformer targeted adjustment of the temperature profile is made possible.
• the invention is based on the generic method in that the feed rates of the air supplied to the first media feed area and the fuel and the feed rate of the fuel supplied to the second medium feed area are coordinated so that the temperature profile of the catalyst assumes a desired course, wherein a total air process air ratio assumes or retains a predetermined value.
• the desired course of the temperature profile is constant. This is a special case of a desired course. It may also be desirable for a temperature in the first reforming zone end region to be slightly higher than in the second reforming zone end region. Also, reverse temperature ratios may be desired. In any case, it is desirable that the temperature differences across the catalyst be reduced.
• the temperature profile is measured. By measuring the temperature profile during reformer operation, it can be determined whether this has a desirable or at least acceptable profile. If this is not the case, the feed rates in the media feed areas are changed until the temperature profile is acceptable, that is, in particular assumes a constant course.
• the temperature profile is known as a function of the reformer output and the supplied fuel and air rates, these dependencies being taken into account in the tuning of the supplied fuel and air rates.
• the dependence of the temperature profile of the reformer performance and the supplied media quantities can be stored in the memory of an electronic control in the form of a map. If the reformer is now operated with a certain output, the characteristic field shows how the feed rates in individual media feed areas are to be selected so that the temperature profile develops in the direction of the desired temperature profile. This map-based method can be used in parallel to that on the - -
• the air supply is substantially constant with constant reformer output.
• the parameters for influencing the air ratios in the two media feed areas are therefore exclusively the fuel feed rates, which are basically sufficient for realizing the method according to the invention.
• a constant air supply in the first media supply region may be sufficient, while in the second media supply region only fuel is introduced.
• air is supplied to the second media feed area.
• the feed rate of the fuel supplied to the first media feed region is given a temperature profile which is characterized by excessively low temperatures in the second reforming zone end region and excessively high temperatures in the first reforming zone end region is lowered while the supply rate of the fuel supplied to the second medium supply area is increased.
• the air ratio increases, resulting in a decrease in the flue gas temperature. Consequently, a reduced amount of heat is supplied to the first reforming zone end portion, whereby its temperature decreases.
• the air ratio pertaining to the overall process is kept constant.
• the invention further relates to a system for reforming fuel, comprising a reformer and an electronic controller, the controller being adapted to control or regulate a method according to any one of the preceding claims.
• the invention is based on the finding that by influencing the media supply of several media supply areas, the system can indeed be operated with a constant air ratio, but a targeted influencing of the temperature profile in the catalyst can be carried out.
• a targeted influencing of the temperature profile in the catalyst can be carried out.
• the heat transfer between the oxidation region and the Refor- m ists Scheme by constructive measures eg. B. modification of the heat exchanger surface or the heat transfer coefficient, is adapted, namely in particular for increased heat transfer at the outlet end of the reforming range and for reduced heat transfer at the inlet end of the reforming region.
• Figure 1 is a schematic representation of a first embodiment of a system according to the invention
• FIG. 2 shows a schematic representation of a second embodiment of a system according to the invention
• Figure 3 is a functional diagram for explaining the invention.
• FIG. 4 shows a flowchart for explaining a method according to the invention.
• Figure 1 shows a schematic representation of a first
• the system 10 comprises a reformer 12 and an electronic controller 44.
• the reformer 12 has a substantially tubular shape with two substantially concentrically arranged regions, namely an oxidation zone 16 and a reforming zone 18, wherein the reforming zone 18 is a catalyst 14 contains.
• the reformer 12 has a first Rulezu111 Siemens 20 with a fuel supply 46, by means of which fuel 32 can be introduced into the Rulezu111 Siemens 20.
• air 34 can be introduced into the media feed region 20 by means of an air feed 48.
• the reformer 12 further includes a second Rulezu réelle Edition 22, fed into the fuel 60 via another fuel feed 50 also _ _
• a further air supply 52 may be provided, via which air 36 is introduced into the second media supply region 22.
• temperature sensors 54, 56, 58 are arranged which detect the temperature of the catalytic converter 14 or the reforming zone 18 at different locations and thus provide information about the temperature profile of the catalytic converter 14 or the reforming zone 18. This temperature information is provided to the electronic controller 44, which also affects the fuel supply rates and air supply rates, namely via the control of fuel metering devices, such as pumps, and blowers.
• the system according to the invention operates as follows.
• the fuel supply 46 supplies fuel 32 to the first media supply region 20, the fuel supply rate being determined by the electronic controller 44.
• air 34 is supplied to the first media supply region 20, and its quantity is also determined by the electronic controller 44.
• Fuel 32 and air 34 mix and enter the oxidation zone 16 via the first oxidation zone end region 24. There, an exothermic reaction takes place, whereby flue gas 38 is formed.
• This flue gas leaves the oxidation zone 16 via the second oxidation zone end region 26 and then reaches the second media feed region 22.
• this second medium feed region 22 at least fuel 60 is introduced via the fuel feed 50, wherein the fuel feed rate is again determined by the electronic control 44.
• additional air 36 can be supplied, and their feed rate through the electronic control 44 is set.
• the further description assumes that the second Rulezu900be- rich 22 has no air supply.
• the flue gas / fuel mixture produced in the second media feed region 22 is fed to the reforming zone 18 and thus to the catalyst 14, where first further exothermic reactions take place in the second reforming zone end region 30.
• water gas shift reactions occur, and subsequently the actual reforming takes place, whereupon the finished reformate 42 can be taken from the reformer 12.
• a temperature profile is determined by the temperature sensors 54, 56, 58, which by way of example are three in the present case, which is characterized by excessively high temperatures in the second reforming zone end region and by temperatures which are too low in the first reforming zone end region, then At a constant air feed rate in the first media feed area 20, the fuel feed rate is lowered while in the second media feed area 22 the fuel feed rate 50 is increased. In this way, the air ratio, which relates to the entire process, remains constant, while the air ratio of the flue gas 38 increases. Consequently, a lower heat output is transferred to the first reforming zone end region 28, resulting in a change in the temperature profile in the reforming zone. If too high temperatures are present in the second end of the reforming zone and too low temperatures in the first end of the reforming zone, this becomes
• the temperature profile can be adapted to the desired course.
• FIG. 2 shows a schematic representation of a second embodiment of a system according to the invention.
• This embodiment corresponds to that of Figure 1, but no temperature sensors are provided which provide signals to the electronic controller 44.
• the variation of the fuel feed rates according to the invention can take place in the individual media supply regions 20, 22, namely on the basis of a characteristic map, which is preferably stored in the electronic control 44 itself. Knowing the temperature profile as a function of the power and the individual media feed rates, the latter can always be adapted so that a desired temperature profile is obtained, namely by taking into account the information stored in the form of the characteristic field.
• FIG. 3 shows a functional diagram for explaining the invention.
• the dependence of the power P Q exiting the oxidation zone 16 on the air ratio of the reacting mixture ⁇ R in the vicinity of the first reforming zone end region 28 is shown, divided into heat output P Q i dissipated to the environment and forming zone 18 or to the catalyst 14 output heat output P Q2 .
• ⁇ R heat output
• the reduction in the air ratio thus makes it possible to increase the heat output delivered to the first reforming zone end region 28;
• an increase in the air ratio ⁇ R leads to a reduction in the first reforming zone.
• nenend Scheme 28 exceeded heat output. Overall, therefore, an adjustment of the temperature profile can take place while maintaining the total number of air processes.
• the output to the environment heat output P Q i can be achieved by suitable measures, eg. B. therm. Isolation can be reduced.
• FIG. 4 shows a flowchart for explaining a method according to the invention.
• the temperature profile in the reforming zone is determined according to step SO1, namely with the aid of temperature sensors and / or with reference to a stored characteristic diagram.
• step S02 it is then checked whether the temperature profile of the reforming zone substantially corresponds to the desired profile. If this is the case, there is no need for improvement, and the method continues with the temperature determination according to step SO1. However, if the temperature profile of the reforming zone is unsatisfactory, the fuel feed rates in the media supply areas are maintained in step S03 while maintaining the
• Air ratio of the overall process changed, in such a way that the temperature profile is optimized. Following this, the determination of the temperature profile according to step SO1 is continued.
• the electronic controller 44 mentioned in connection with the present invention may be a controller dedicated to the refurbishment process. Usefully, however, the control shown can also at least partially take over the other control functions of the entire fuel cell system.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Inorganic Chemistry (AREA)
• Hydrogen, Water And Hydrids (AREA)

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• 2006
  • 2006-08-30 DE DE102006040563A patent/DE102006040563A1/de not_active Ceased
• 2007
  • 2007-07-10 JP JP2009525908A patent/JP2010501461A/ja not_active Withdrawn
  • 2007-07-10 CN CNA2007800317274A patent/CN101594930A/zh active Pending
  • 2007-07-10 EA EA200970228A patent/EA200970228A1/ru unknown
  • 2007-07-10 CA CA002660688A patent/CA2660688A1/en not_active Abandoned
  • 2007-07-10 AU AU2007291696A patent/AU2007291696A1/en not_active Abandoned
  • 2007-07-10 WO PCT/DE2007/001225 patent/WO2008025314A1/de active Application Filing
  • 2007-07-10 US US12/377,443 patent/US20100166646A1/en not_active Abandoned
  • 2007-07-10 EP EP07801135A patent/EP2056959A1/de not_active Withdrawn

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