WO2006013455A1 - Method and apparatus for producing clean reducing gases from coke oven gas - Google Patents

Method and apparatus for producing clean reducing gases from coke oven gas Download PDF

Info

Publication number
WO2006013455A1
WO2006013455A1 PCT/IB2005/002297 IB2005002297W WO2006013455A1 WO 2006013455 A1 WO2006013455 A1 WO 2006013455A1 IB 2005002297 W IB2005002297 W IB 2005002297W WO 2006013455 A1 WO2006013455 A1 WO 2006013455A1
Authority
WO
WIPO (PCT)
Prior art keywords
gas
coke oven
reducing gas
steam
utilizing
Prior art date
Application number
PCT/IB2005/002297
Other languages
French (fr)
Inventor
Eugenio Zendejas-Martinez
Original Assignee
Hylsa, S.A. De C.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 Hylsa, S.A. De C.V. filed Critical Hylsa, S.A. De C.V.
Priority to MX2007001249A priority Critical patent/MX2007001249A/en
Priority to CN2005800263152A priority patent/CN101023023B/en
Priority to DE112005001881T priority patent/DE112005001881T5/en
Publication of WO2006013455A1 publication Critical patent/WO2006013455A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
    • C10J3/58—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels combined with pre-distillation of the fuel
    • C10J3/60—Processes
    • C10J3/64—Processes with decomposition of the distillation products
    • C10J3/66—Processes with decomposition of the distillation products by introducing them into the gasification zone
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/48—Sulfur compounds
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
    • C01B13/02—Preparation of oxygen
    • C01B13/0229—Purification or separation processes
    • C01B13/0248—Physical processing only
    • 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
    • C01B3/36—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 oxygen or mixtures containing oxygen as gasifying agents
    • 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
    • C01B3/50—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
    • C10K1/00—Purifying combustible gases containing carbon monoxide
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/0073—Selection or treatment of the reducing gases
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/02—Making spongy iron or liquid steel, by direct processes in shaft furnaces
    • 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
    • C01B2203/025—Processes for making hydrogen or synthesis gas containing a partial oxidation step
    • C01B2203/0255—Processes for making hydrogen or synthesis gas containing a partial oxidation step containing a non-catalytic partial oxidation step
    • 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
    • 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
    • C01B2203/0485—Composition of the impurity the impurity being a sulfur compound
    • 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
    • C01B2203/08—Methods of heating or cooling
    • C01B2203/0872—Methods of cooling
    • C01B2203/0888—Methods of cooling by evaporation of a fluid
    • C01B2203/0894—Generation of steam
    • 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
    • C01B2203/84—Energy production
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2210/00—Purification or separation of specific gases
    • C01B2210/0043—Impurity removed
    • C01B2210/0046—Nitrogen
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/16—Integration of gasification processes with another plant or parts within the plant
    • C10J2300/1671—Integration of gasification processes with another plant or parts within the plant with the production of electricity
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/20—Increasing the gas reduction potential of recycled exhaust gases
    • C21B2100/28—Increasing the gas reduction potential of recycled exhaust gases by separation
    • C21B2100/282—Increasing the gas reduction potential of recycled exhaust gases by separation of carbon dioxide
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/40—Gas purification of exhaust gases to be recirculated or used in other metallurgical processes
    • C21B2100/42—Sulphur removal
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
    • C21B2100/62—Energy conversion other than by heat exchange, e.g. by use of exhaust gas in energy production
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
    • C21B2100/66—Heat exchange
    • 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
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/10—Reduction of greenhouse gas [GHG] emissions
    • Y02P10/122—Reduction of greenhouse gas [GHG] emissions by capturing or storing 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/10—Reduction of greenhouse gas [GHG] emissions
    • Y02P10/134—Reduction of greenhouse gas [GHG] emissions by avoiding CO2, e.g. using hydrogen

Definitions

  • the invention refers to a process and system for producing reducing gases mainly composed of hydrogen and carbon monoxide from coke-making operations where coal is transformed into metallurgical coke, and more particularly to a process wherein the volatile components derived from coal are . transformed into reducing gases suitable for chemical utilization as synthesis gas, as a reducing agent for direct reduction of iron ores and/or as a clean fuel.
  • coal is heated in order to eliminate most of the volatile components and preserving mostly the carbon structure. Coke is thereby provided with the physical and chemical properties which make it fit for providing energy and burden support in blast furnaces.
  • Volatile .matter of coal comprises a number of compounds which are distilled in coke ovens constituting what is known as coke oven gas.
  • the volume and composition of coke oven gas depends on the characteristics of the coal utilized but typically untreated coke oven gas comprises about 44% of water, about 29% of hydrogen, about 3% of carbon monoxide, about 13% of methane and many impurities as ammonia, sulfur, benzene-type compounds, etc.
  • coke oven gas Since coke oven gas has a high calorific value, it is utilized mostly for heating purposes in steel plants. Typically, coke oven gas is cooled, cleaned and treated in a number of chemical processes for separating valuable compounds such as ammonia and other petrochemicals and for removing sulfur before the gas is finally burned. Cleaning of coke oven gas requires a complex and costly chemical plant.
  • British Patent Specification No. 1 ,566,970 describes a process for the treatment of coke oven gas.
  • This patent recognizes the value of performing a partial combustion of coke oven gas in order to produce a reducing gas useful for direct reduction of iron ores.
  • the partial combustion transforms coke oven gas into a cracked gas rich in carbon monoxide and hydrogen.
  • the partial combustion process of this patent however has a number of disadvantages and does not teach or suggest a process and apparatus which integrates the energy in an improved way.
  • the present invention provides a method and apparatus with a practical and economical way of using the coke oven gas by cooling it immediately after the partial combustion cracking and also utilizing the heat produced in said partial combustion for at least two specific purposes which are critical for the operation of the reduction reactor: e.g. for the CO2 removal unit of the recycled reducing gas to the shaft reactor, and also for the sulfur removal unit needed for cleaning the coke oven gas prior to its utilization.
  • the present invention provides a method of treating hot crude coke oven gas produced in coke ovens comprising: mixing said hot crude coke oven gas with an oxygen-containing gas in order to carry out a partial combustion of said coke oven gas producing a reducing gas having a high content of hydrogen and carbon monoxide at a temperature higher than about 1000 0 C; passing said hot reducing gas through a heat exchanger in order to produce high temperature steam; utilizing a first portion of said steam to produce electricity; removing sulfur compounds and other impurities of said reducing gas in a sulfur removing unit; and utilizing a second portion of said steam in said sulfur removing unit.
  • the method further includes an additional step of utilizing at least a portion of said clean reducing gas in a direct reduction plant comprising a direct reduction reactor, a CO2 removal unit and a gas heater.
  • the method further includes the additional step of utilizing a third portion of said exhausted steam in said CO2 removal unit of said direct reduction plant.
  • Figure 1 is a schematic process diagram of a preferred embodiment of the invention.
  • Figure 2 illustrates an example of the process showing, in a schematic process diagram similar to Figure 1 , values of process parameters.
  • Figure 3 is a table supplementing the information of process streams shown in Figure 2.
  • Figure 4 also illustrates another example of the process showing, in a schematic process diagram of a direct reduction plant, values of process parameters operating according to the coke oven gas cleaning method of the invention. Detailed description of the invention
  • numeral 10 designates a battery of coke ovens, to which coal 12 is charged and heated therein by combustion of gases 14 and air 16.
  • Coke 18 is discharged from ovens 10 in a manner known in the art and hot crude coke oven gas 20 is produced typically at a temperature of about 600°C degrees to 700°C.
  • Hot crude coke oven gas 20 is then mixed with an oxygen-containing gas 22 which may be produced in an air separation plant 24 from air 26.
  • the air separation plant 24 may be of the cryogenic or a PSA-type since the purity of oxygen is not critical for this application.
  • the process may also operate with oxygen-enriched air, although the quality of the resulting reducing gas is affected by the amount of nitrogen from said air feed.
  • Hot crude coke oven gas 20 at a temperature of about 650°C is subject to a partial combustion with oxygen 22 in combustion chamber 28 reaching temperatures above about 1000 0 C. At this temperature all organic compounds are converted into a high temperature reducing gas 30 mainly composed of a mixture of hydrogen and carbon monoxide, carbon dioxide, methane and water.
  • Reducing gas 30 is passed through a heat exchanger 32 where it heats steam 34 from steam drum 36 and super-heated steam 38 is utilized in turbine 40 to produce electricity in electric generator 42. Electricity is fed through line 44 and is used in air separation plant 24 to produce oxygen for the partial combustion of coke oven gas.
  • a first portion 50 of exhausted steam 46 from turbine 40 is used in sulfur separation unit 48 and a second portion 52 is used in the CO2 separation unit 54 of a direct reduction plant.
  • the reducing gas After passing through heat exchanger 32, the reducing gas is fed to a boiler 56 where steam 58 is produced from water 60 and is held in steam drum 36. From boiler 56, reducing gas 62 is finally quenched by direct contact with water in cooler 64. Condensed water is withdrawn through pipe 66. Cold reducing gas 68 is then fed to blower 70 and then led through pipe 72 to be treated in a sulfur removal unit 48 in a manner known in the art producing solid sulfur 74 and a stream of clean reducing gas 76.
  • a portion of the reducing gas 76 is used for heating the coke ovens through pipe 14 and another portion 78 is compressed in compressor 80 to be injected to the reduction gas loop of a direct reduction reactor 82.
  • Iron oxides bearing particles 84 for example iron ore pellets, lumps or mixtures thereof, are fed to reduction reactor 82 and descend by gravity through said reactor where they are contacted with high temperature reducing gases 86, for example above 900 0 C whereby iron oxides are reduced to metallic iron, known as DRI or sponge iron 88, and discharged from the lower part of the reduction reactor 82 to be utilized in steelmaking operations.
  • Reacted reducing gas 90 is withdrawn from reactor 82 and cooled down in cooler 92 where water is removed from the gas by condensation a portion of the cooled gas 94 is recycled to the reduction reactor and another portion 96 may be vented from the reduction loop and used for example in gas heater 98.
  • the recycled reducing gas portion 94 is compressed in compressor 100 and fed to a carbon dioxide removal unit 54 where CO2 is removed from the system thus regenerating the reducing potential of the recycled gas by elimination of water 102 and CO2 104 which are the main products of the reduction reactions carried out in reactor 82.

Abstract

A process and system for producing reducing gases are disclosed, wherein volatile components derived from coal are transformed into reducing gases suitable for utilization as synthesis gas, as a reducing agent for the direct reduction of iron ores and/or as a clean fuel.

Description

Title
Method and Apparatus for producing clean reducing gases from coke oven gas. Field of the invention
The invention refers to a process and system for producing reducing gases mainly composed of hydrogen and carbon monoxide from coke-making operations where coal is transformed into metallurgical coke, and more particularly to a process wherein the volatile components derived from coal are . transformed into reducing gases suitable for chemical utilization as synthesis gas, as a reducing agent for direct reduction of iron ores and/or as a clean fuel. Background of the invention
It is known that in the process of producing metallurgical coke, coal is heated in order to eliminate most of the volatile components and preserving mostly the carbon structure. Coke is thereby provided with the physical and chemical properties which make it fit for providing energy and burden support in blast furnaces. Volatile .matter of coal comprises a number of compounds which are distilled in coke ovens constituting what is known as coke oven gas. The volume and composition of coke oven gas depends on the characteristics of the coal utilized but typically untreated coke oven gas comprises about 44% of water, about 29% of hydrogen, about 3% of carbon monoxide, about 13% of methane and many impurities as ammonia, sulfur, benzene-type compounds, etc.
Since coke oven gas has a high calorific value, it is utilized mostly for heating purposes in steel plants. Typically, coke oven gas is cooled, cleaned and treated in a number of chemical processes for separating valuable compounds such as ammonia and other petrochemicals and for removing sulfur before the gas is finally burned. Cleaning of coke oven gas requires a complex and costly chemical plant.
A number of proposals are found in patents and other technical literature for utilizing coke oven gas after cleaning, alone or in combination with other gases, for iron reduction purposes or for steam and electricity generation. US Patent No. 4,178,266 describes a process for conveying hot crude coke oven gas generated in coke ovens to a position of utilization while preventing condensation of higher hydrocarbons. This patent teaches to increase the temperature of the coke oven gas by injecting an oxygen-containing gas into the coke oven gas stream so that it is partially combusted. Such injection of oxygen may increase the temperature of the mixture to about 95O0C to 15000C. The purpose of the oxygen injection is to avoid condensation of impurities and of higher hydrocarbons, thereby preventing many problems in the gas conveying systems. This patent does not teach or suggest carrying out a partial combustion of coke oven gas for producing a high-quality reducing gas.
British Patent Specification No. 1 ,566,970 describes a process for the treatment of coke oven gas. This patent recognizes the value of performing a partial combustion of coke oven gas in order to produce a reducing gas useful for direct reduction of iron ores. The partial combustion transforms coke oven gas into a cracked gas rich in carbon monoxide and hydrogen. The partial combustion process of this patent however has a number of disadvantages and does not teach or suggest a process and apparatus which integrates the energy in an improved way.
US Patent No. 4,235,624 describes a method for processing coke oven gas almost identical to the method of the above- referred British patent 1 ,566,970. This patent does not teach or suggest the integration of thermal energy in the treatment and cleaning of coke oven gas comprising a partial combustion step as the present invention.
US Patent No. 4,235,624 describes a method for processing coke oven gas almost identical to the method of the above-referred British patent 1 ,566,970. Although this patent teaches generally that the coke oven gas may be used as a reducing gas in an iron ore reduction shaft furnace, no detail is provided about a preferred manner of utilizing the integration of the thermal energy that the coke oven gas contains. As a matter of fact, the claims of this patent specify that the invention lies in the utilization of hot_coke oven gas, that means that the coke oven gas is fed to the reactor without cooling it before its introduction into the shaft reactor. This process scheme has a number of disadvantages since all equipment involved in the handling and conduction of the coke oven gas from the coke ovens to the shaft reactor must be prepared for high-temperature operation.
In contrast, the present invention provides a method and apparatus with a practical and economical way of using the coke oven gas by cooling it immediately after the partial combustion cracking and also utilizing the heat produced in said partial combustion for at least two specific purposes which are critical for the operation of the reduction reactor: e.g. for the CO2 removal unit of the recycled reducing gas to the shaft reactor, and also for the sulfur removal unit needed for cleaning the coke oven gas prior to its utilization. Objects of the Invention
It is therefore an object of the present invention to provide a process and system for treating coke oven gas in order to produce a reducing gas comprising hydrogen and carbon monoxide, particularly useful for the direct reduction of iron ores.
It is another object of the present invention to provide a process and system for treating coke oven gas and producing a synthesis gas useful as raw material in chemical processes or for producing heat, steam, electricity or power avoiding the complex and expensive cleaning processes normally utilized in coking plants.
Other objects of the invention will be pointed out in this specification or will be evident to those skilled in the art. Summary of the invention
The present invention provides a method of treating hot crude coke oven gas produced in coke ovens comprising: mixing said hot crude coke oven gas with an oxygen-containing gas in order to carry out a partial combustion of said coke oven gas producing a reducing gas having a high content of hydrogen and carbon monoxide at a temperature higher than about 10000C; passing said hot reducing gas through a heat exchanger in order to produce high temperature steam; utilizing a first portion of said steam to produce electricity; removing sulfur compounds and other impurities of said reducing gas in a sulfur removing unit; and utilizing a second portion of said steam in said sulfur removing unit.
In a preferred embodiment of the invention the method further includes an additional step of utilizing at least a portion of said clean reducing gas in a direct reduction plant comprising a direct reduction reactor, a CO2 removal unit and a gas heater.
In another preferred embodiment of the invention the method further includes the additional step of utilizing a third portion of said exhausted steam in said CO2 removal unit of said direct reduction plant. ' Brief description of the drawings
Figure 1 is a schematic process diagram of a preferred embodiment of the invention.
Figure 2 illustrates an example of the process showing, in a schematic process diagram similar to Figure 1 , values of process parameters.
Figure 3 is a table supplementing the information of process streams shown in Figure 2.
Figure 4 also illustrates another example of the process showing, in a schematic process diagram of a direct reduction plant, values of process parameters operating according to the coke oven gas cleaning method of the invention. Detailed description of the invention
The invention will be described with reference to the accompanying drawings, it being understood that many changes and modifications may be made by those skilled in the art without departing from the spirit of the invention, which is defined by the appended claims.
With reference to Figure 1 , numeral 10 designates a battery of coke ovens, to which coal 12 is charged and heated therein by combustion of gases 14 and air 16. Coke 18 is discharged from ovens 10 in a manner known in the art and hot crude coke oven gas 20 is produced typically at a temperature of about 600°C degrees to 700°C. Hot crude coke oven gas 20 is then mixed with an oxygen-containing gas 22 which may be produced in an air separation plant 24 from air 26. The air separation plant 24 may be of the cryogenic or a PSA-type since the purity of oxygen is not critical for this application. The process may also operate with oxygen-enriched air, although the quality of the resulting reducing gas is affected by the amount of nitrogen from said air feed.
Hot crude coke oven gas 20 at a temperature of about 650°C is subject to a partial combustion with oxygen 22 in combustion chamber 28 reaching temperatures above about 10000C. At this temperature all organic compounds are converted into a high temperature reducing gas 30 mainly composed of a mixture of hydrogen and carbon monoxide, carbon dioxide, methane and water.
Reducing gas 30 is passed through a heat exchanger 32 where it heats steam 34 from steam drum 36 and super-heated steam 38 is utilized in turbine 40 to produce electricity in electric generator 42. Electricity is fed through line 44 and is used in air separation plant 24 to produce oxygen for the partial combustion of coke oven gas.
A first portion 50 of exhausted steam 46 from turbine 40 is used in sulfur separation unit 48 and a second portion 52 is used in the CO2 separation unit 54 of a direct reduction plant.
After passing through heat exchanger 32, the reducing gas is fed to a boiler 56 where steam 58 is produced from water 60 and is held in steam drum 36. From boiler 56, reducing gas 62 is finally quenched by direct contact with water in cooler 64. Condensed water is withdrawn through pipe 66. Cold reducing gas 68 is then fed to blower 70 and then led through pipe 72 to be treated in a sulfur removal unit 48 in a manner known in the art producing solid sulfur 74 and a stream of clean reducing gas 76.
A portion of the reducing gas 76 is used for heating the coke ovens through pipe 14 and another portion 78 is compressed in compressor 80 to be injected to the reduction gas loop of a direct reduction reactor 82. Iron oxides bearing particles 84, for example iron ore pellets, lumps or mixtures thereof, are fed to reduction reactor 82 and descend by gravity through said reactor where they are contacted with high temperature reducing gases 86, for example above 9000C whereby iron oxides are reduced to metallic iron, known as DRI or sponge iron 88, and discharged from the lower part of the reduction reactor 82 to be utilized in steelmaking operations.
Reacted reducing gas 90 is withdrawn from reactor 82 and cooled down in cooler 92 where water is removed from the gas by condensation a portion of the cooled gas 94 is recycled to the reduction reactor and another portion 96 may be vented from the reduction loop and used for example in gas heater 98. The recycled reducing gas portion 94 is compressed in compressor 100 and fed to a carbon dioxide removal unit 54 where CO2 is removed from the system thus regenerating the reducing potential of the recycled gas by elimination of water 102 and CO2 104 which are the main products of the reduction reactions carried out in reactor 82. Example
A computer-model calculation of a plant incorporating the invention was made and the results are illustrated in figures 2, 3 and 4. This example clearly shows the advantages of the invention regarding its application for obtaining a reducing gas for producing good-quality direct reduced iron.

Claims

1. A method of treating hot crude coke oven gas from a coke oven to produce a clean reducing gas, comprising partially combusting the hot crude coke oven gas at a temperature greater than about 10000C by mixing the hot crude coke oven gas with an oxygen- containing gas to produce a hot reducing gas having a high content of hydrogen and carbon monoxide; producing high temperature steam by passing the hot reducing gas through a heat exchanger; utilizing a first portion of the steam to produce electricity; and utilizing a second portion of the steam in a sulfur removing unit to remove sulfur compounds and other impurities from the reducing gas to produce the clean reducing gas.
2. The method of claim 1 , further comprising utilizing at least a portion of the clean reducing gas in a direct reduction plant comprising a direct reduction reactor, a CO2 removal unit and a gas heater.
3. The method of claim 2, further comprising utilizing a third portion of said steam in the CO2 removal unit of the direct reduction plant.
4. The method of claim 3, wherein the direct reduction plant is used to directly reduce iron ore.
5. The method of claim 2, wherein a portion of the clean reducing gas is used to heat the coke oven.
6. The method of claim 5, wherein another portion of the clean reducing gas is injected into the direct reduction reactor.
7. A method of reducing iron oxides in a shaft reduction reactor utilizing coke oven gas, comprising mixing hot crude coke oven gas with an oxygen-containing gas in order to carry out a partial combustion of said coke oven gas to produce a hot reducing gas having a high content of hydrogen and carbon monoxide at a temperature higher than about 10000C; passing said hot reducing gas through a heat exchanger in order to produce high temperature steam; utilizing a first portion of said steam in a sulfur removal unit for removing sulfur compounds and other impurities of said reducing gas; and utilizing a second portion of said steam in a CO2 removal unit where exhausted reducing gas is treated to remove carbon dioxide before being recycled into said shaft reduction reactor.
PCT/IB2005/002297 2004-08-03 2005-08-02 Method and apparatus for producing clean reducing gases from coke oven gas WO2006013455A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
MX2007001249A MX2007001249A (en) 2004-08-03 2005-08-02 Method and apparatus for producing clean reducing gases from coke oven gas.
CN2005800263152A CN101023023B (en) 2004-08-03 2005-08-02 Method and apparatus for producing clean reducing gases from coke oven gas
DE112005001881T DE112005001881T5 (en) 2004-08-03 2005-08-02 Process and apparatus for producing pure reducing gases from coke oven gas

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US59819704P 2004-08-03 2004-08-03
US60/598,197 2004-08-03

Publications (1)

Publication Number Publication Date
WO2006013455A1 true WO2006013455A1 (en) 2006-02-09

Family

ID=35429154

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2005/002297 WO2006013455A1 (en) 2004-08-03 2005-08-02 Method and apparatus for producing clean reducing gases from coke oven gas

Country Status (5)

Country Link
US (1) US20060027043A1 (en)
CN (1) CN101023023B (en)
DE (1) DE112005001881T5 (en)
MX (1) MX2007001249A (en)
WO (1) WO2006013455A1 (en)

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007024312B4 (en) * 2007-05-24 2009-04-30 Lurgi Gmbh Method and apparatus for producing reducing gas and / or fuel gas for the direct reduction of iron ore
BR112012002266A2 (en) * 2009-07-31 2017-08-08 Danieli Off Mecc "method and apparatus for producing direct reduced iron in a direct reduction system"
DE102009042520A1 (en) * 2009-09-22 2011-03-24 Uhde Gmbh Method for operating a coke oven arrangement
JP5495749B2 (en) 2009-12-10 2014-05-21 三菱重工業株式会社 Hydrogen production facility and power plant
US8496730B2 (en) * 2010-05-14 2013-07-30 Midrex Technologies, Inc. System and method for reducing iron oxide to metallic iron using coke oven gas and oxygen steelmaking furnace gas
CN101871031B (en) * 2010-06-01 2011-08-03 中国石油大学(北京) Method and equipment for preparing reducing gas from coke oven gas to produce sponge iron
IT1402250B1 (en) * 2010-09-29 2013-08-28 Danieli Off Mecc PROCEDURE AND EQUIPMENT FOR THE PRODUCTION OF DIRECT REDUCTION IRON USING A REDUCING GAS SOURCE INCLUDING HYDROGEN AND CARBON MONOXIDE
AT510955B1 (en) * 2011-05-30 2012-08-15 Siemens Vai Metals Tech Gmbh REDUCTION OF METAL OXIDES USING A BOTH HYDROCARBONS AND HYDROGEN CONTAINING GAS STREAM
WO2013027084A1 (en) * 2011-08-20 2013-02-28 Hyl Technologies, S.A. De C.V. Process for producing direct reduced iron (dri) utilizing gases derived from coal
CN104245963B (en) * 2011-12-21 2016-11-16 伊尔技术有限公司 Utilize the method and apparatus that oven gas prepares DRI (DRI)
AU2014273996B2 (en) * 2013-05-30 2018-11-01 Clean Coal Technologies, Inc. Treatment of coal
CN113249536A (en) 2013-07-22 2021-08-13 沙特基础工业公司 Use of top gas in direct reduction process
CN103525965B (en) * 2013-10-08 2015-12-02 中国石油大学(北京) Coke(oven)gas on-catalytic is utilized to transform the method and system of producing gas base directly reducing iron
CN103525966B (en) * 2013-10-08 2016-05-25 中国石油大学(北京) Utilize Catalytic Conversion of Natural Gas to produce the method and system of gas base directly reducing iron
CN103525964B (en) * 2013-10-08 2016-05-25 中国石油大学(北京) Utilize oven gas catalyzed conversion to produce the method and system of gas base directly reducing iron
DE102013113933A1 (en) * 2013-12-12 2015-06-18 Thyssenkrupp Ag Process for the production of synthesis gas in association with a metallurgical plant
DE102013113913A1 (en) * 2013-12-12 2015-06-18 Thyssenkrupp Ag Plant network for steelmaking and process for operating the plant network
DE102013113958A1 (en) * 2013-12-12 2015-06-18 Thyssenkrupp Ag Plant network for steelmaking and process for operating the plant network
DE102013113921A1 (en) 2013-12-12 2015-06-18 Thyssenkrupp Ag Plant network for steelmaking and process for operating the plant network
DE102013113942A1 (en) * 2013-12-12 2015-06-18 Thyssenkrupp Ag Method for reducing CO2 emissions during operation of a metallurgical plant
DE102013113950A1 (en) 2013-12-12 2015-06-18 Thyssenkrupp Ag Plant network for steelmaking and process for operating the plant network
CN103834760B (en) * 2014-02-25 2016-02-17 中国石油大学(北京) A kind of method and device utilizing coal mine gas preparing synthetic gas production reduced iron
RU2675581C2 (en) 2014-07-15 2018-12-19 Мидрэкс Текнолоджиз, Инк. Methods and systems for obtaining iron of direct reduction and gaseous fuel for steel plant
CN106241736A (en) * 2016-08-03 2016-12-21 西南化工研究设计院有限公司 A kind of technique utilizing coke-stove gas extraction metallurgy reducing gases
US11021766B2 (en) * 2016-11-03 2021-06-01 Midrex Technologies, Inc. Direct reduction with coal gasification and coke oven gas
KR20200110705A (en) * 2018-02-12 2020-09-24 란자테크, 인크. Process to improve carbon conversion efficiency
CN114574648B (en) * 2020-12-02 2023-10-31 北京京诚泽宇能源环保工程技术有限公司 System and method for preparing reducing gas of gas-based shaft furnace
JP2022157631A (en) * 2021-03-31 2022-10-14 Ｊｆｅスチール株式会社 Manufacturing method of reduced iron, and manufacturing apparatus of reduced iron

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1566970A (en) * 1976-08-26 1980-05-08 Didier Eng Process for the treatment of coke-oven gas
US4235624A (en) * 1977-07-27 1980-11-25 Didier Engineering Gmbh Method for processing coke oven gas
EP0916739A2 (en) * 1997-11-03 1999-05-19 Texaco Development Corporation Gasification process and plant for direct reduction reactors

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2700044A1 (en) * 1977-01-03 1978-07-06 Didier Eng METHOD FOR PREVENTING CONDENSATION DURING THE TRANSPORT OF HOT COOKING RAW GASES TO THE APPLICATION POINT
IE63440B1 (en) * 1989-02-23 1995-04-19 Enserch Int Investment Improvements in operating flexibility in integrated gasification combined cycle power stations

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1566970A (en) * 1976-08-26 1980-05-08 Didier Eng Process for the treatment of coke-oven gas
US4235624A (en) * 1977-07-27 1980-11-25 Didier Engineering Gmbh Method for processing coke oven gas
EP0916739A2 (en) * 1997-11-03 1999-05-19 Texaco Development Corporation Gasification process and plant for direct reduction reactors

Also Published As

Publication number Publication date
CN101023023A (en) 2007-08-22
CN101023023B (en) 2012-12-26
DE112005001881T5 (en) 2007-06-21
US20060027043A1 (en) 2006-02-09
MX2007001249A (en) 2007-03-23

Similar Documents

Publication Publication Date Title
US20060027043A1 (en) Method and apparatus for producing clean reducing gases from coke oven gas
US20220235426A1 (en) Method and system for producing steel or molten-iron-containing materials with reduced emissions
EP2798293B1 (en) Method of producing molten iron in a blast furnace with top-gas recycle
RU2643007C2 (en) Reduction of iron oxide to metallic iron using natural gas
RU2439165C2 (en) Direct reduction method of iron oxides to metallic iron, which uses gas of coke ovens or gas similar to it
JP5857054B2 (en) Method and apparatus for directly producing reduced iron using a reducing gas containing hydrogen and carbon monoxide as a supply source
CN102037145B (en) Method for melting raw iron while recirculating blast furnace gas by adding hydrocarbons
EP2794932B1 (en) Method and plant for production of direct reduced iron (dri) utilizing coke oven gas
CN102712959A (en) Method for producing direct reduced iron with limited CO2 emissions
CN104017923A (en) Ironmaking method and ironmaking furnace system
TWI803522B (en) Method for producing hot synthesis gas, in particular for use in blast furnace operation
WO2005104708A2 (en) Method and apparatus for gasifying waste automotive tires to produce high quality solid carbon and non-condensable synthesis gas
JP5860469B2 (en) Method and equipment for producing coke during indirect heating gasification
KR101254977B1 (en) Apparatus and Method for Treating Coke Oven Gas
CN113825845B (en) Method for operating a metallurgical furnace
CN105733689A (en) Preparation system and method for reducing gas for gas-based shaft kiln
KR20240041974A (en) How to make iron melt
KR20240016962A (en) How blast furnace equipment operates

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 BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

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

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: MX/a/2007/001249

Country of ref document: MX

WWE Wipo information: entry into national phase

Ref document number: 200580026315.2

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 1120050018814

Country of ref document: DE

RET De translation (de og part 6b)

Ref document number: 112005001881

Country of ref document: DE

Date of ref document: 20070621

Kind code of ref document: P

122 Ep: pct application non-entry in european phase