WO2002048027A1 - Procede et installation pour l'elaboration d'ammoniac - Google Patents

Procede et installation pour l'elaboration d'ammoniac Download PDF

Info

Publication number
WO2002048027A1
WO2002048027A1 PCT/NL2001/000898 NL0100898W WO0248027A1 WO 2002048027 A1 WO2002048027 A1 WO 2002048027A1 NL 0100898 W NL0100898 W NL 0100898W WO 0248027 A1 WO0248027 A1 WO 0248027A1
Authority
WO
WIPO (PCT)
Prior art keywords
stream
discharge
reformer
feed
hydrocarbon
Prior art date
Application number
PCT/NL2001/000898
Other languages
English (en)
Inventor
Jacobus Johannes De Wit
Original Assignee
Continental Engineering B.V.
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 Continental Engineering B.V. filed Critical Continental Engineering B.V.
Priority to AU2002219713A priority Critical patent/AU2002219713A1/en
Publication of WO2002048027A1 publication Critical patent/WO2002048027A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
    • C01C1/00—Ammonia; Compounds thereof
    • C01C1/02—Preparation, purification or separation of ammonia
    • C01C1/04—Preparation of ammonia by synthesis in the gas phase
    • C01C1/0405—Preparation of ammonia by synthesis in the gas phase from N2 and H2 in presence of a catalyst
    • 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
    • C01B3/025—Preparation or purification of gas mixtures for ammonia synthesis
    • 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
    • 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
    • C01B3/48—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 followed by reaction of water vapour with carbon monoxide
    • 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
    • C01B2203/02—Processes for making hydrogen or synthesis gas
    • C01B2203/0283—Processes for making hydrogen or synthesis gas containing a CO-shift step, i.e. a water gas shift step
    • C01B2203/0294—Processes for making hydrogen or synthesis gas containing a CO-shift step, i.e. a water gas shift step containing three or more CO-shift steps
    • 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
    • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
    • C01B2203/0415—Purification by absorption in liquids
    • 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
    • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
    • C01B2203/042—Purification by adsorption on solids
    • 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
    • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
    • C01B2203/0435—Catalytic purification
    • C01B2203/0445—Selective methanation
    • 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
    • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
    • C01B2203/0465—Composition of the impurity
    • C01B2203/0475—Composition of the impurity the impurity being carbon dioxide
    • 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
    • C01B2203/06—Integration with other chemical 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
    • C01B2203/06—Integration with other chemical processes
    • C01B2203/068—Ammonia synthesis
    • 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
    • C01B2203/0811—Methods of heating the process for making hydrogen or synthesis gas by combustion of fuel
    • 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
    • C01B2203/0833—Heating by indirect heat exchange with hot fluids, other than combustion gases, product gases or non-combustive exothermic reaction product gases
    • 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
    • C01B2203/08—Methods of heating or cooling
    • C01B2203/0805—Methods of heating the process for making hydrogen or synthesis gas
    • C01B2203/0866—Methods of heating the process for making hydrogen or synthesis gas by combination of different heating methods
    • 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
    • C01B2203/0872—Methods of cooling
    • C01B2203/0883—Methods of cooling by indirect heat exchange
    • 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
    • C01B2203/10—Catalysts for performing the hydrogen forming reactions
    • C01B2203/1041—Composition of the catalyst
    • C01B2203/1047—Group VIII metal catalysts
    • C01B2203/1052—Nickel or cobalt catalysts
    • 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
    • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
    • C01B2203/1205—Composition of the feed
    • C01B2203/1211—Organic compounds or organic mixtures used in the process for making hydrogen or synthesis gas
    • C01B2203/1235—Hydrocarbons
    • 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
    • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
    • C01B2203/1205—Composition of the feed
    • C01B2203/1211—Organic compounds or organic mixtures used in the process for making hydrogen or synthesis gas
    • C01B2203/1235—Hydrocarbons
    • C01B2203/1241—Natural gas or methane
    • 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
    • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
    • C01B2203/1258—Pre-treatment of the feed
    • 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
    • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
    • C01B2203/1258—Pre-treatment of the feed
    • C01B2203/1264—Catalytic pre-treatment of the feed
    • C01B2203/127—Catalytic desulfurisation
    • 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
    • C01B2203/143—Three or more 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
    • C01B2203/14—Details of the flowsheet
    • C01B2203/146—At least two purification steps in series
    • C01B2203/147—Three or more purification 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
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/10—Process efficiency
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • the invention relates to a novel production process for ammonia that is highly integrated as far as heat balance is concerned.
  • the techniques used are also suitable for improving existing plants for ammonia production.
  • the invention leads to a more energy efficient process per tonne of ammonia produced that is also able to provide its own electricity requirement or is able to export electrical energy.
  • ammonia synthesis gas is produced by bringing a normal hydrocarbon feed and steam into an endothermic, catalytic conversion zone operating under primary reformer conditions (primary reformer), by which means a primary reformed gas stream is produced that is brought with air into an adiabatic, catalytic conversion zone that is operating under autothermal steam reforming conditions, so that a crude, hot, ammonia synthesis gas is produced that is then fed to the endothermic catalytic conversion zone in indirect heat exchange with the hydrocarbon feed and steam in order to provide the heat for conversion in the endothermic zone.
  • primary reformer primary reformer
  • Air required for the operation of the adiabatic zone is supplied by a centrifugal compressor driven by a gas turbine.
  • the exhaust from the gas turbine exchanges heat with the air for the secondary reformer and the heated compressed air, which is then introduced into the secondary reformer.
  • WO 9748639 describes a synthesis gas production system that comprises a gas turbine and an autothermal reformer (ATR), wherein the autothermal reformer is positioned between the compressor and expander of the gas turbine and wherein the ATR produces synthesis gas and can serve as the burner for the gas turbine.
  • ATR autothermal reformer
  • US 4 792 441 describes ammonia synthesis in which a small proportion of the methane stream flows to the primary reformer and a major proportion of the methane stream goes to the secondary reformer. This document further describes the saturation of natural gas with steam (Figure 1). Air enriched with oxygen is used for the secondary reformer.
  • the energy saving indicated above is achieved in accordance with three aspects of the invention.
  • the first aspect relates to the use of a gas turbine with extraction of process air, with electricity generation coupled thereto.
  • the residual heat from the gas turbine is in the first instance returned to the process.
  • the second aspect relates to a reformer section, which comprises an (optional) prereformer, a primary reformer and a secondary reformer.
  • An additional energy saving is achieved by heat exchange in the primary reformer between the discharge stream from the secondary reformer and the stream from the prereformer.
  • the third aspect of the invention relates to carrying out the conventional CO shift conversion in three steps at successively decreasing temperature instead of the conventional two steps.
  • the invention relates in particular to a combination of the abovementioned three aspects, which leads to maximum energy saving.
  • the present invention now provides, according to a first aspect, a method for the preparation of ammonia, which method comprises the following steps: a) a reforming step, in which a hydrocarbon stream, a process air stream and steam are reacted to obtain a discharge stream which contains CO, CO 2 , H 2 and N 2 ; b) a CO conversion step, in which CO in the discharge stream from step a) is converted to CO 2 and H 2 ; c) a CO 2 removal step, in which CO 2 is removed from the stream obtained in step b); and d) a methanisation step, in which the residual CO and CO 2 are converted to CH 4 and H 2 O; in such a way that a synthesis gas that contains N 2 and H 2 , suitable for the production of ammonia, is obtained, after which the synthesis gas is converted to ammonia in a synthesis cycle, characterised in that at least a portion of the process air stream that is reacted in the reforming step is compressed with the aid of a compressor which is part of
  • a gas turbine is installed that is partly driven by residual gases from the process.
  • a generator that generates electricity is coupled to the gas turbine.
  • the discharge gases from the gas turbine can advantageously be used to heat process streams and to generate steam.
  • a suitable heat exchanger in particular a waste heat boiler, can be used for this purpose.
  • the hydrocarbon stream can comprise LPG, naphtha or natural gas, but in general will be natural gas. If necessary, sulphur can be removed from the hydrocarbon stream, since sulphur, present in natural gas, would poison the catalysts used. This is carried out, for example, in two steps. In the first step organically bound sulphur is reacted with hydrogen over a CoMoX or CuMoX catalyst to give hydrogen sulphide (H 2 S). In the second step H 2 S is removed by binding to ZnO. The feed for the desulphurisation is first preheated by the discharge stream from the gas turbine to a temperature of 300 - 350 °C. The gas finally leaves the desulphurisation section at a temperature of approximately 150 °C.
  • the gas stream is now, in particular, first fed through a column and saturated with water vapour.
  • Process condensate is preferably used for this purpose.
  • the quantity of water to be discharged or the quantity of process condensate to be stripped off is reduced by this means.
  • the requirement for process steam is also reduced by the same step.
  • medium-pressure steam is produced in this way, whilst this process step is in a temperature range in which normally only low-pressure steam could be generated.
  • An installation is also provided for carrying out the method according to the first aspect of the invention, which installation comprises: a) a reformer section for reacting a hydrocarbon stream, a process air stream and steam; b) a CO conversion section connected via pipework to the reformer section, for converting CO present in a discharge stream from the reformer section into CO 2 and H 2 ; c) a CO 2 removal section connected via pipework to the CO conversion section, ⁇ for removal of CO 2 from a discharge stream from the CO conversion section; d) a methanisation section, connected via pipework to the CO 2 removal section, for converting the residual CO and CO 2 into CH 4 and H 2 O; characterised in that the installation is also provided with e) a gas turbine, comprising a compressor provided with a feed for air and a discharge for compressed air; a combustion chamber provided with an inlet for fuel, an inlet for compressed air connected via pipework to the discharge for compressed air from the compressor and an outlet for combustion gas; an expansion turbine provided with an inlet for combustion gas connected via pipe
  • the compressor and expansion turbine in this installation are coupled via a shaft.
  • the gas turbine is also coupled to a generator for generating electricity.
  • a person skilled in the art can determine which type of gas turbine is suitable for the invention. Examples are standard gas turbines, where the requisite quantity of process air can be tapped off, or a "tailor-made" machine, made up of discrete elements with a compression ratio of 8 - 35 bar.
  • the outlet for combustion gas from the expansion turbine is coupled via pipework to a heat exchanger suitable for heat exchange between the combustion gas and at least the process air stream and the hydrocarbon stream, in particular a waste heat boiler. Heat exchangers of this type are known to those skilled in the art.
  • the present invention provides a method, in particular in combination with the first aspect of the invention, wherein the reaction of the hydrocarbon stream and process air stream in the reformer section takes place in the following successive steps: ai) a primary reforming step, in which a major proportion of the methane in the hydrocarbon stream is converted in the presence of steam to carbon oxides and hydrogen; aii) a secondary reforming step, in which the stream obtained in step ai) and the process air stream are converted to carbon oxides and hydrogen.
  • the primary reforming step is preceded by aiii) a prereforming step in which higher hydrocarbons in the hydrocarbon stream are converted to methane and a portion of the methane is converted to carbon oxides and H 2 .
  • aiii) higher hydrocarbons (such as ethane, propane, up to naphtha) are converted to methane and a portion of the methane is converted to carbon oxides and H 2
  • higher hydrocarbons such as ethane, propane, up to naphtha
  • This residual heat from the reformer section can be used to heat the incoming process gas before and/or after the prereforming step.
  • Prereforming takes place in a catalyst bed at a temperature of 500 - 525 °C. As a result of the endothermic reaction, the gas temperature falls by approximately 50 °C.
  • step ai which is either the first or the second step in the reformer section
  • the stream obtained in step ai) is converted to carbon oxides and hydrogen at a temperature of 700 - 750 °C.
  • the mixture is passed over a nickel catalyst in a tube reactor, in which the reaction takes place. Because the reaction is endothermic, the pipes are heated from the outside using natural gas combustion.
  • the secondary reforming step aii) is then carried out. If the standard quantity of process air is used, the outlet temperature of 700 - 750 °C of the primary reformer is too low to achieve adequate conversion of methane in the secondary reformer, needed for the ammonia synthesis. Therefore, pre-heated, oxygen-enriched air is added in an autothermal reactor, known as a post-combustion chamber or secondary reformer, an exothermic reaction allowing the temperature to rise to approximately 1000 °C. The methane content falls to 0.3 - 0.5 % and at the same time nitrogen, which is needed for the ammonia synthesis, is added by means of the process air supplied.
  • an autothermal reactor known as a post-combustion chamber or secondary reformer
  • the secondary reformer and the catalyst used therein are the same as those used in the standard process.
  • the reformer section comprises: ai) a primary reformer provided with a feed for hydrocarbon stream and provided with a discharge for reacted hydrocarbon stream; aii) a secondary reformer provided with a feed for reacted hydrocarbon stream coupled via pipework to the discharge from the primary reformer, a feed for process air stream and a discharge for reacted hydrocarbon stream.
  • the reformer section also comprises aiii) a prereformer provided with a feed for the hydrocarbon stream and provided with a discharge for reacted hydrocarbon stream, which is coupled via pipework to the feed of the primary reformer.
  • the CO content Downstream of the secondary reformer the CO content is approximately 13 %.
  • the major proportion of the CO is converted to CO 2 and additional hydrogen by passing the gas mixture over two catalysts.
  • the invention provides, in particular in combination with the first and/or second aspect of the invention, a method in which the CO conversion step b) is carried out in the following steps: bi) a high temperature step, in which the stream obtained in the reforming step is reacted at a temperature of 300 - 360 °C, a discharge stream being obtained; bii) a medium temperature step, in which the discharge stream from step bi) is reacted at a temperature of 200 - 250 °C, a discharge stream being obtained; biii) a low temperature step, in which the discharge stream from step bii) is reacted at a temperature of 190 - 200 °C.
  • the equilibrium of the water gas shift reaction is less advantageous. This effect is reduced by carrying out the CO conversion not in two but in three steps. Residual heat is recovered after each step.
  • the high temperature CO conversion takes place at a lower feed temperature (340 °C) than in the existing process (360 °C).
  • the final step has an outlet temperature of 195 °C.
  • the invention also provides an installation for carrying out the method according to the third aspect, which comprises a CO conversion section, comprising bi) a first conversion reactor operating at high temperature, provided with a feed coupled via pipework to the discharge for reacted hydrocarbon from the reformer section, and with a discharge; bii) a second conversion reactor operating at medium temperature, provided with a feed coupled via pipework to the discharge from the first conversion reactor, and with a discharge; biii) a third conversion reactor operating at low temperature, provided with a feed coupled via pipework to the discharge from the second conversion reactor, and with a discharge.
  • a CO conversion section comprising bi) a first conversion reactor operating at high temperature, provided with a feed coupled via pipework to the discharge for reacted hydrocarbon from the reformer section, and with a discharge; bii) a second conversion reactor operating at medium temperature, provided with a feed coupled via pipework to the discharge from the first conversion reactor, and with a discharge; biii) a third conversion reactor operating at low temperature, provided with a feed coupled via pipe
  • the installation is also provided with an installation for saturating the hydrocarbon stream with water, provided with a feed for the hydrocarbon stream, a discharge for the hydrocarbon stream saturated with water vapour, which discharge is coupled via pipework to the feed to the reformer section, and a feed and discharge for circulation water, wherein the feed and discharge for circulation water forms a cycle via pipework, wherein at least one heat exchanger is incorporated in the cycle equipped for heat exchange between the discharge lines from one or more of the conversion reactors and the water circulation cycle.
  • a suitable absorbent This is, for example, an amine solution or an alkaline solvent based on K 2 CO 3 .
  • the solution is regenerated by using some of the heat that is available in the gas after the CO conversion for the K 2 CO 3 process, supplemented by a quantity of low- pressure steam, available from back-pressure turbines, which are used to drive pumps and compressors, or by heat which is withdrawn from the top vapour stream from the process condensate stripper. At least 60 % of the energy costs for regeneration can be saved by selecting a suitable absorbent.
  • CO 2 absorbent with which the minimum amount of regeneration energy is demanded.
  • the CO 2 is preferably removed using aMDEA, but the use of Selexol is also a possibility.
  • the CO and the residual CO 2 (100 to 1000 ppm) in the gas are reacted with H 2 to give CH 4 and H 2 O by passing the gas at a temperature of 300 °C over a nickel catalyst (methanisation).
  • the reaction that applies here is the reverse of that in the first conversion of methane, but because of the low water content and the low temperature the CO and CO 2 are now converted to less than 1 ppm. Thus, some of the H 2 produced is lost again in this step.
  • the crude synthesis gas has the correct H 2 :N 2 ratio of 3:1.
  • the synthesis gas is now compressed to approximately 100 - 220 bar with the aid of a centrifugal compressor, in a number of stages with intermediate cooling.
  • the final stage of the compressor is provided with a planet wheel for circulation of the gas through the synthesis cycle.
  • the compressor is driven by a 100 - 220 bar steam turbine with possible 40 bar extraction and a (partial) condensation turbine.
  • the residual water is removed from the synthesis gas with the aid of molecular sieves upstream of the first or upstream of the second stage of the compressor.
  • the heat that is liberated during the process is used for generation of steam that can be used elsewhere in the process.
  • the synthesis reaction takes place in two reactors with two beds in the first reactor.
  • the conversion for each complete synthesis loop is increased, which leads to a smaller recirculation stream and less ammonia cooling.
  • Figure 1 shows an installation according to the first aspect of the invention
  • Figure 2 shows an installation according to the second aspect of the invention
  • Figure 3 shows an installation according to the third aspect of the invention
  • Figure 4 shows an example of a complete ammonia process in which the aspects of the invention have been integrated.
  • Figure 1 shows the first aspect of the invention, a portion of the process air stream being compressed with the aid of the compressor 2, which forms part of the gas turbine 1.
  • the air to be compressed is fed via 5 to the compressor 2 and a compressed air stream 7 leaves the compressor 2.
  • a portion of this air stream is fed at ' 8 to the burner 4 of the gas turbine.
  • Fuel is supplied to the burner via 18.
  • the off-gases 9 from the burner are fed to the expansion turbine 3 of the gas turbine.
  • the gases are fed to a heat exchanger (waste heat boiler) 11 to heat process streams and to generate steam.
  • the gas turbine is furthermore provided with a shaft 6, by means of which the compressor 2 and the expander 3 are coupled. Moreover, a generator 17, by means of which electricity can be generated, is coupled to the gas turbine.
  • the process air stream 7 that leaves the compressor is fed via an additional compressor 14 and line 15 via the waste heat boiler 11 to the reformer section 16. Additional oxygen is fed to the process air stream 7 at 13.
  • the natural gas required in the reformer section is fed to the reformer section via 12, through the waste heat boiler 11 and the natural gas saturating unit 25 (shown diagrammatically).
  • FIG. 2 shows the second aspect of the invention, that is to say the construction of the reformer section.
  • a gas stream 40 which optionally has been desulphurised and saturated with water vapour and to which the requisite quantity of process steam has been added, enters the prereformer 41 and leaves this at 42. This stream then passes to the GHR 43 and leaves this at 45, in order then to be fed to the secondary reformer 46.
  • a process air stream 15, which is enriched with oxygen, is fed to the secondary reformer.
  • the outgoing stream from the secondary reformer 47 passes to the GHR 43, where heat exchange with the process stream 42 takes place. Finally, this stream leaves the GHR at 44 and, after heat recovery in 52, is then fed to the CO conversion section 49.
  • Figure 3 shows the third aspect of the invention, that is to say the performance of the
  • An air stream 15 is also fed to the reformer section 16.
  • the stream issuing from the reformer section passes at 44 to a first CO conversion reactor 26 and leaves the latter at 33 and is then fed to CO conversion reactor 27 and leaves the latter at 34 and is then fed to CO conversion 28 and leaves the latter via 35 in order, after heat recovery in 53, then to be fed to the CO 2 removal section 36.
  • the outgoing streams 33; 34 and 35 from the CO conversion reactors undergo heat exchange with the water stream 24 via heat exchangers 29, 30 and 31 , respectively.
  • FIG. 4 An example of a complete ammonia process in which all three aspects of the invention are incorporated is shown in Figure 4.
  • the gas turbine is indicated by 1.
  • a process air stream 5 is fed to the compressor 2 of the gas turbine and leaves the latter via 7.
  • a portion of this air stream passes via 8 to the combustion chamber 4 and leaves the latter via 9 in order then to be expanded in expander 3 in order to be fed via 10 to the waste heat boiler.
  • Fuel is fed to the combustion chamber 4 of the gas turbine via 18.
  • the compressed process air stream 7 passes via compressor 14 and via line 15, heat being exchanged in the waste heat boiler 11, to the secondary reformer 46.
  • the hydrocarbon stream for example a natural gas stream, passes via 12 and the waste heat boiler 11 to the desulphurisation reactor 50. Following heat exchange with stream 12 in 100, the hydrocarbon stream is fed via line 20 to the saturating unit 25 and leaves the latter at 40 in order then to be fed to prereformer 41. Steam can be fed to the hydrocarbon stream 40 at 51 and heat exchange between the outgoing stream 44 from the GHR 43 takes place at 52.
  • the outgoing stream 42 from the prereformer 41 is fed to the GHR at the top and, after reaction, leaves the latter via 45 in order to be fed to the secondary reformer 46. Heat is exchanged between the outgoing stream 47 from the secondary reformer 46 and the process stream 42 in the GHR. A stream 44 then issues from the GHR, which stream 44 is fed to the first CO conversion reactor 26. The outgoing stream 33 from the first CO conversion reactor 26 then passes to the second CO conversion reactor 27 and, via 34, to the third CO conversion reactor 28. Via heat exchangers 29, 30 and 31 heat is exchanged between the streams 33, 34 and 35 and the water stream 24 to the natural gas saturating unit 25.
  • the stream 35 passes to the CO 2 removal installation 55, in which CO 2 is adsorbed on aMDEA (but Selexol is also a possibility).
  • Gas stream 56 (free from CO 2 ) issues from the CO 2 absorption column, which stream is discharged via a liquid separator 57 as stream 58.
  • the solvent stream 59 then issues from the CO 2 absorption column 55, which solvent stream 59 is fed to the stripper 60.
  • the adsorbed CO 2 is removed from the solvent by means of heat.
  • stream 67 is circulated over a heat exchanger 54. The requisite heat is supplied by stream 35.
  • the CO 2 removed from the solvent is cooled in condenser 63. Condensate produced is separated off in liquid separator 64 and returned as stream 66 to the stripper.
  • the CO 2 gas stream 65 issues from the liquid separator.

Landscapes

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

Abstract

L'invention concerne un procédé relatif à l'élaboration d'ammoniac, à niveau élevé d'intégration en termes d'équilibre thermique. Selon un premier aspect, on utilise une turbine à gaz à extraction d'air de processus, avec couplage de production électrique. La chaleur résiduelle de la turbine à gaz est d'abord réinjectée dans le processus. Selon un deuxième aspect, on décrit un reformeur qui comprend un préreformeur (éventuellement), un reformeur primaire et un reformeur secondaire. On augmente encore les économies d'énergie grâce à l'échange thermique intervenant dans le reformeur primaire entre le flux de décharge du reformeur secondaire et le flux du préreformeur. Selon un troisième aspect, on décrit l'exécution de la conversion catalytique de CO classique, en trois étapes qui font intervenir successivement des températures décroissantes - au lieu des deux étapes habituelles.
PCT/NL2001/000898 2000-12-11 2001-12-11 Procede et installation pour l'elaboration d'ammoniac WO2002048027A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002219713A AU2002219713A1 (en) 2000-12-11 2001-12-11 Process and apparatus for the production of ammonia

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1016848A NL1016848C2 (nl) 2000-12-11 2000-12-11 Werkwijze en inrichting voor de bereiding van ammoniak.
NL1016848 2000-12-11

Publications (1)

Publication Number Publication Date
WO2002048027A1 true WO2002048027A1 (fr) 2002-06-20

Family

ID=19772563

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL2001/000898 WO2002048027A1 (fr) 2000-12-11 2001-12-11 Procede et installation pour l'elaboration d'ammoniac

Country Status (3)

Country Link
AU (1) AU2002219713A1 (fr)
NL (1) NL1016848C2 (fr)
WO (1) WO2002048027A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005080257A1 (fr) * 2004-02-20 2005-09-01 Herbert Gehmair Procede pour produire du gaz de synthese pour une synthese d'ammoniac par reformage a la vapeur de gaz naturel
EP1698588A1 (fr) * 2005-03-04 2006-09-06 Ammonia Casale S.A. Procédé de préparation d'ammoniac
EP2321386A1 (fr) * 2008-07-18 2011-05-18 Kellogg Brown & Root LLC Reformage par oxydation catalytique partielle
WO2011077107A1 (fr) * 2009-12-22 2011-06-30 Johnson Matthey Plc Conversion d'hydrocarbures en dioxyde de carbone et en énergie électrique
EP2404869A1 (fr) * 2010-07-06 2012-01-11 Ammonia Casale S.A. Procédé de production d'un gaz ammoniac de synthèse
US9102534B2 (en) 2009-12-22 2015-08-11 Johnson Matthey Plc Conversion of hydrocarbons to carbon dioxide and electrical power
EP2910523A1 (fr) * 2014-02-21 2015-08-26 Haldor Topsoe A/S Procédé de méthanisation avec un milieu d'échange de chaleur passif
EP3623343A1 (fr) * 2018-09-11 2020-03-18 Casale Sa Procédé de synthèse de l'ammoniac
WO2022060355A1 (fr) * 2020-09-16 2022-03-24 Exxonmobil Research And Engineering Company Production d'ammoniac et d'urée dans des réacteurs à flux inverse
RU2788872C2 (ru) * 2018-09-11 2023-01-25 Касале Са Способ синтеза аммиака

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1325172A (en) * 1969-11-10 1973-08-01 Exxon Research Engineering Co Water gas shift process
US4161393A (en) * 1977-03-07 1979-07-17 Metallgesellschaft Aktiengesellschaft Shift conversion of raw gas from gasification of coal
US4479925A (en) * 1982-09-13 1984-10-30 The M. W. Kellogg Company Preparation of ammonia synthesis gas
US4778670A (en) * 1984-03-02 1988-10-18 Imperial Chemical Industries Plc Technical hydrogen
DE19719997A1 (de) * 1997-05-13 1998-05-28 Daimler Benz Ag Reformierungsreaktoranlage und Betriebsverfahren hierfür
NL1013478C2 (nl) * 1999-05-27 2000-11-28 Plug Power Inc Brandstofprocessor voor het produceren van waterstof en inrichting geschikt voor gebruik in een dergelijke processor voor het uit een eerste en tweede gasstroom genereren van een derde en vierde gasstroom.

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1325172A (en) * 1969-11-10 1973-08-01 Exxon Research Engineering Co Water gas shift process
US4161393A (en) * 1977-03-07 1979-07-17 Metallgesellschaft Aktiengesellschaft Shift conversion of raw gas from gasification of coal
US4479925A (en) * 1982-09-13 1984-10-30 The M. W. Kellogg Company Preparation of ammonia synthesis gas
US4778670A (en) * 1984-03-02 1988-10-18 Imperial Chemical Industries Plc Technical hydrogen
DE19719997A1 (de) * 1997-05-13 1998-05-28 Daimler Benz Ag Reformierungsreaktoranlage und Betriebsverfahren hierfür
NL1013478C2 (nl) * 1999-05-27 2000-11-28 Plug Power Inc Brandstofprocessor voor het produceren van waterstof en inrichting geschikt voor gebruik in een dergelijke processor voor het uit een eerste en tweede gasstroom genereren van een derde en vierde gasstroom.

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
EVANS T: "LEAST COST APPROACHES TO AMMONIA PLANT EFFICIENCY", N&M. NITROGEN AND METHANOL,BRITISH SULPHUR PUBLISHING, LONDON,GB, no. 232, 1 March 1998 (1998-03-01), pages 41 - 42,44-52, XP000740078, ISSN: 1462-2378 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005080257A1 (fr) * 2004-02-20 2005-09-01 Herbert Gehmair Procede pour produire du gaz de synthese pour une synthese d'ammoniac par reformage a la vapeur de gaz naturel
EP1698588A1 (fr) * 2005-03-04 2006-09-06 Ammonia Casale S.A. Procédé de préparation d'ammoniac
WO2006094619A1 (fr) * 2005-03-04 2006-09-14 Ammonia Casale S.A. Procede de synthese d'ammoniaque
EP2321386A1 (fr) * 2008-07-18 2011-05-18 Kellogg Brown & Root LLC Reformage par oxydation catalytique partielle
EP2321386A4 (fr) * 2008-07-18 2011-11-30 Kellogg Brown & Root Llc Reformage par oxydation catalytique partielle
AU2010334600B2 (en) * 2009-12-22 2015-02-05 Johnson Matthey Plc Conversion of hydrocarbons to carbon dioxide and electrical power
WO2011077107A1 (fr) * 2009-12-22 2011-06-30 Johnson Matthey Plc Conversion d'hydrocarbures en dioxyde de carbone et en énergie électrique
US9216903B2 (en) 2009-12-22 2015-12-22 Johnson Matthey Plc Conversion of hydrocarbons to carbon dioxide and electrical power
US9102534B2 (en) 2009-12-22 2015-08-11 Johnson Matthey Plc Conversion of hydrocarbons to carbon dioxide and electrical power
CN102971251A (zh) * 2010-07-06 2013-03-13 阿梅尼亚·卡萨莱股份有限公司 用于生产氨合成气的工艺
WO2012004032A1 (fr) * 2010-07-06 2012-01-12 Ammonia Casale Sa Procédé pour la production de gaz de synthèse d'ammoniac
RU2565321C2 (ru) * 2010-07-06 2015-10-20 Касале Са Способ получения синтез-газа для производства аммиака
EP2404869A1 (fr) * 2010-07-06 2012-01-11 Ammonia Casale S.A. Procédé de production d'un gaz ammoniac de synthèse
US10087074B2 (en) 2010-07-06 2018-10-02 Casale Sa Process for producing ammonia synthesis gas
EP2910523A1 (fr) * 2014-02-21 2015-08-26 Haldor Topsoe A/S Procédé de méthanisation avec un milieu d'échange de chaleur passif
EP3623343A1 (fr) * 2018-09-11 2020-03-18 Casale Sa Procédé de synthèse de l'ammoniac
WO2020052832A1 (fr) * 2018-09-11 2020-03-19 Casale Sa Procédé de synthèse d'ammoniac
RU2788872C2 (ru) * 2018-09-11 2023-01-25 Касале Са Способ синтеза аммиака
WO2022060355A1 (fr) * 2020-09-16 2022-03-24 Exxonmobil Research And Engineering Company Production d'ammoniac et d'urée dans des réacteurs à flux inverse

Also Published As

Publication number Publication date
NL1016848C2 (nl) 2002-06-13
AU2002219713A1 (en) 2002-06-24

Similar Documents

Publication Publication Date Title
US20220194789A1 (en) Atr-based hydrogen process and plant
US9102534B2 (en) Conversion of hydrocarbons to carbon dioxide and electrical power
US9216903B2 (en) Conversion of hydrocarbons to carbon dioxide and electrical power
US4264567A (en) Method for producing a hydrogen-containing gas
US20230271829A1 (en) ATR-Based Hydrogen Process and Plant
US20230174377A1 (en) Process for the production of hydrogen
US20230174378A1 (en) Process for producing hydrogen
NO158616B (no) Fremgangsmaate for fremstilling av ammoniakk.
RU2519940C2 (ru) Способ синтеза метанола
US5068058A (en) Production of ammonia synthesis gas
WO2002048027A1 (fr) Procede et installation pour l'elaboration d'ammoniac
JPH0798643B2 (ja) アンモニア合成ガスの製造方法
JPS606281B2 (ja) 水素の製造方法
US20230264145A1 (en) Improving the purity of a CO2-rich stream
WO2024056871A1 (fr) Procédé de reformage autothermique pour la production d'hydrogène
WO2024056870A1 (fr) Reformage atr
WO2023217804A1 (fr) Procédé et installation pour la production d'un gaz de synthèse
AU2023215807A1 (en) Low-carbon hydrogen process
WO2023242536A1 (fr) Procédé de production d'hydrogène
EA041183B1 (ru) Рециркуляция углерода в процессе парового риформинга

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)