Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J19/18—Stationary reactors having moving elements inside
  • B01J19/20—Stationary reactors having moving elements inside in the form of helices, e.g. screw reactors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J19/18—Stationary reactors having moving elements inside
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2/00—Lime, magnesia or dolomite
  • C04B2/10—Preheating, burning calcining or cooling
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
  • C10B7/00—Coke ovens with mechanical conveying means for the raw material inside the oven
  • C10B7/10—Coke ovens with mechanical conveying means for the raw material inside the oven with conveyor-screws
• • 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
  • C10J3/007—Screw type gasifiers
• • 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
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/06—Continuous processes
  • C10J3/12—Continuous processes using solid heat-carriers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F27—FURNACES; KILNS; OVENS; RETORTS
  • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
  • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
  • F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
  • F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path tunnel furnace
  • F27B9/24—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path tunnel furnace being carried by a conveyor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00051—Controlling the temperature
  • B01J2219/00074—Controlling the temperature by indirect heating or cooling employing heat exchange fluids
  • B01J2219/00076—Controlling the temperature by indirect heating or cooling employing heat exchange fluids with heat exchange elements inside the reactor
  • B01J2219/00078—Fingers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00051—Controlling the temperature
  • B01J2219/0015—Controlling the temperature by thermal insulation means
  • B01J2219/00155—Controlling the temperature by thermal insulation means using insulating materials or refractories
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00051—Controlling the temperature
  • B01J2219/00157—Controlling the temperature by means of a burner
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00049—Controlling or regulating processes
  • B01J2219/00051—Controlling the temperature
  • B01J2219/00159—Controlling the temperature controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/18—Details relating to the spatial orientation of the reactor
  • B01J2219/182—Details relating to the spatial orientation of the reactor horizontal
• • 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
  • C10J2200/00—Details of gasification apparatus
  • C10J2200/15—Details of feeding means
  • C10J2200/152—Nozzles or lances for introducing gas, liquids or suspensions
• • 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
  • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
  • C10J2300/0903—Feed preparation
• • 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
  • C10J2300/12—Heating the gasifier
  • C10J2300/1246—Heating the gasifier by external or indirect heating

Definitions

• the present invention concerns a reactor for heating and treating materials in a controlled atmosphere, by a continuous process.
• the invention can be employed for reducing metal oxides, but it can be employed also for different treatments, such as coal degassing, lime roasting, metal melting and so on.
• a known reactor of this kind comprises a rotating cylinder in which the material to be reduced is heated by direct irradiation and the reducing fluids are insufflated through ducts solidary with the cylinder.
• the known system is not satisfactory for various reasons: direct irradiation of the material does not allow a strong and uniform heating of the mass; the methane and the combustible oils are relatively expensive hydrogen sources; the system is complex due to the need both of connecting the ducts solidary with the rotating cylinder to stationary feeders, and of controlling air supply so as to avoid reoxidation of the material.
• a reactor and a process for treating materials in a controlled atmosphere are provided, which reactor and process allow high reaction speeds without need to employ expensive materials, ensure a uniform heating and require no complex feeding apparatus.
• the invention provides a reactor comprising a reaction chamber associated at one end, in its upper part, with means for introducing a charge of a first material to be treated, and at the opposite end, in its lower part, with means for discharging the treated materials, characterized in that the reactor further comprises: means for the introduction of further materials into the lower part of the reaction chamber, in alternative or in addition to the first material and below the latter; means for indirect heating of the materials introduced and for continuously stirring said materials and advancing them towards the discharge means; and means, located in the upper part of the reaction chamber, for introducing oxidizing gas which exothermically reacts with the gases evolved during the treatment, the indirect heating means being arranged so as to continuously move between the upper and the lower parts of the chamber, being heated in the upper part by the heat evolved by said hexothermic reaction and yielding said heat, in the lower part of the chamber, to the materials being treated.
• the invention further provides a process where a first material to be treated is introduced into a reaction chamber at a first end thereof, and the treated material is discharged from a second end of the chamber, characterized in that the first material is introduced into the upper part of the chamber so as to fall on the chamber floor; in that further materials, which become covered by the first material, are introduced into the lower part of the chamber, in alternative or in addition to the first material; and in that the materials on the reaction chamber floor are continuously stirred, are made to move towards the discharge end and are indirectly heated by heating means which are movable between the upper and the lower parts of the chamber and which yield the heat absorbed in the upper part of the chamber to materials being treated.
• the reactor comprises a treatment chamber 1 where a refractory cylinder 2 rotates.
• the cylinder is equipped with parallel rows of fins 3, e.g. made of refractory steel, which are arranged concentrically with the cylinder and are mounted thereto. These fins are to make the materials present in the chamber advance, while stirring and homogenizing them, and to indirectly heat same, by yielding them heat absorbed in the upper part of chamber 1, as will be better explained hereinafter.
• Cylinder 2 is supported by a shaft 4, driven by a motor-reducer 5 and cooled by a coolant liquid introduced through a rotating seal 6.
• chamber 1 The upper part of chamber 1 is in communication with a preheater 7, it too comprising a rotating cylinder 8 equipped on its inner surface with radial fins oriented according to the generatrices of cylinder 8.
• a charge 9 e.g. finely subdivided metal oxides
• Charge 9 is introduced into preheater 7 by means of a conveyer belt 10, a hopper 11 and a chute 12.
• Preheater 7 is rotated by means of wheels 13 which rest on suitable supporting structure (not shown), and is associated with chimney 14 for gas exhaust.
• chamber 1 is associated with a device 15 for discharging the treated material from the chamber bottom, for instance a screw driven by a motor- reducer 16. That screw is located within a tube 17 which can be associated with cooling means, if the material is a completely treated product, or which will be thermally insulated from the outer environment, if the material treated in the reactor is to undergo further thermal treatment.
• a device 15 for discharging the treated material from the chamber bottom for instance a screw driven by a motor- reducer 16. That screw is located within a tube 17 which can be associated with cooling means, if the material is a completely treated product, or which will be thermally insulated from the outer environment, if the material treated in the reactor is to undergo further thermal treatment.
• Fig. 2 further shows that the reactor comprises a group of feeders 18 (for instance screws operated by respective motor-reducers 19) for the possible introduction into the lower part of chamber 1 , below the primary charge 9 and at a plurality of locations spaced apart along the chamber, of a secondary solid charge, for instance coal in powder or in grains.
• a duct 21 communicating with tubes 20 (Fig.3) housing screws 18, allows mixing liquid substances with the coal, for instance combustible oils which are introduced together with or through the coal.
• Other ducts 22 can convey gaseous materials, for instance methane, propane, etc., into the lower part of chamber 1. Also those materials can be introduced in alternative or in addition to the coal and/or the combustible oils.
• the materials supplied through feeders 18 and ducts 21, 22 will generally be introduced in different amounts at the different locations along chamber 1 , so that just the amount of material actually needed by the reactions at a given location will be provided at that location.
• Fig.3 shows that ducts 24 with nozzles 25 are provided in the upper part of chamber 1 to introduce oxidizing agents (e.g. air) into the chamber for reaction gas combustion. That combustion is the main heat source for heating fins 3.
• oxidizing agents e.g. air
• the operation of the reactor is as follows.
• the primary charge 9 fed through the hopper 11 falls into preheater 7 where it is made to advance towards chamber 1 and is heated by the hot fumes leaving chamber 1.
• Charge 9 passes from preheater 7 into chamber 1 where it falls on the secondary solid charge fed through feeders 18 and/or on the fluid substances introduced through ducts 21, 22.
• the mass present in the lower part of chamber 1 is stirred by fins 3 of cylinder 2, which fins make the mass advance towards discharge means 15 and, above all, yield absorbed while in the upper part of the chamber to the mass heat.
• the continuous stirring ensures a homogeneous heating. While the mass advances, it is combined with new amounts of solid secondary charge and/or of fluids to the extent necessary to maintain the reactions.
• the gases released by the reactions between the oxides and the reducing substances pass then to the upper part of chamber 1 where they burn due to the action of air or other oxidizing gases introduced through ducts 24, thereby heating fins 3 while they move in the upper part of chamber 1. If it is necessary to supplement the heat provided by such combustion, also burners 23 will be operated.
• the indirect heating of the material Thanks to the indirect heating of the material, a good separation is maintained between the atmospheres of the upper and lower parts of chamber 1 (oxidizing and oxidized atmosphere in the upper part, reducing atmosphere in the lower part), so that the risk that the material becomes reoxidized is kept limited.
• the material is discharged through tube 17, where the same atmosphere as in the lower part of the chamber is maintained.
• the reactor optimally exploits the ancillary materials (coal, combustible oils, natural gases) since those materials are introduced along the whole reactor length and in different amounts.
• ancillary materials coal, combustible oils, natural gases
• coal which is a cheap material, can be employed as ancillary material, while maintaining high reaction speeds.
• materials of granulometry even considerably smaller than that usually utilised, as the mass is continuously stirred by the fins and agitated also by the gases, if any, introduced from below, so that a high porosity is maintained even with finely divided materials.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Combustion & Propulsion (AREA)
• Ceramic Engineering (AREA)
• Thermal Sciences (AREA)
• Physics & Mathematics (AREA)
• Structural Engineering (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Muffle Furnaces And Rotary Kilns (AREA)
• Control Of Heat Treatment Processes (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=11413011

Family Applications (1)

Country Status (12)

Families Citing this family (7)

Family Cites Families (4)

• 1994
  • 1994-12-28 IT IT94TO001078A patent/IT1267362B1/it active IP Right Grant
• 1995
  • 1995-11-07 JP JP8520053A patent/JPH10511450A/ja active Pending
  • 1995-11-07 CA CA002208835A patent/CA2208835A1/en not_active Abandoned
  • 1995-11-07 EP EP95938429A patent/EP0800640A1/en not_active Withdrawn
  • 1995-11-07 BR BR9510432A patent/BR9510432A/pt not_active Application Discontinuation
  • 1995-11-07 WO PCT/EP1995/004372 patent/WO1996020381A1/en not_active Application Discontinuation
  • 1995-11-07 PL PL95320959A patent/PL320959A1/xx unknown
  • 1995-11-07 CN CN95197159.XA patent/CN1171840A/zh active Pending
  • 1995-11-07 AU AU39823/95A patent/AU3982395A/en not_active Abandoned
  • 1995-11-07 MX MX9704773A patent/MX9704773A/es unknown
  • 1995-12-13 ZA ZA9510621A patent/ZA9510621B/xx unknown
• 1997
  • 1997-06-25 FI FI972746A patent/FI972746A0/fi not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events