[go: up one dir, main page]

WO2005061411A1 - Monolithic castable refractory - Google Patents

Monolithic castable refractory Download PDF

Info

Publication number
WO2005061411A1
WO2005061411A1 PCT/US2004/042861 US2004042861W WO2005061411A1 WO 2005061411 A1 WO2005061411 A1 WO 2005061411A1 US 2004042861 W US2004042861 W US 2004042861W WO 2005061411 A1 WO2005061411 A1 WO 2005061411A1
Authority
WO
WIPO (PCT)
Prior art keywords
refractory material
monolithic refractory
monolithic
dispersant
carbon black
Prior art date
Legal status (The legal status 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 status listed.)
Ceased
Application number
PCT/US2004/042861
Other languages
French (fr)
Inventor
Samuel B. Bonsall
George M. Stoupis
David A. Knowlton
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vesuvius Crucible Co
Original Assignee
Vesuvius Crucible Co
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 Vesuvius Crucible Co filed Critical Vesuvius Crucible Co
Publication of WO2005061411A1 publication Critical patent/WO2005061411A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/013—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics containing carbon
    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
    • C04B35/62645—Thermal treatment of powders or mixtures thereof other than sintering
    • C04B35/62665—Flame, plasma or melting treatment
    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • C04B2235/3222—Aluminates other than alumino-silicates, e.g. spinel (MgAl2O4)
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3817—Carbides
    • C04B2235/3826—Silicon carbides
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/42—Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
    • C04B2235/422—Carbon
    • C04B2235/424—Carbon black
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/42—Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
    • C04B2235/422—Carbon
    • C04B2235/425—Graphite
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/48—Organic compounds becoming part of a ceramic after heat treatment, e.g. carbonising phenol resins
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5427—Particle size related information expressed by the size of the particles or aggregates thereof millimeter or submillimeter sized, i.e. larger than 0,1 mm
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5445—Particle size related information expressed by the size of the particles or aggregates thereof submicron sized, i.e. from 0,1 to 1 micron

Definitions

  • the present invention relates to monolithic refractory materials, and in particular a low- toxicity castable refractory having excellent corrosion resistance and spalling resistance. Description of the related art.
  • monolithic refractory materials are often used as linings for vessels such as ladles that transport the molten metal throughout the process.
  • carbon-bonded materials are typically used.
  • the monolithic refractories generally comprise a refractory aggregate and a binder.
  • Various binders have been used throughout the years, including binders utilizing coal tar pitch.
  • U.S. Patent No. 4,184,883 discloses a pitch-bonded refractory that utilizes a cure accelerator such as calcium nitrate to accelerate the rate of increase of the softening point of the pitch in order to decrease the amount of spalling that occurs during burn-in and the early heats of the refractory.
  • U.S. Patent No. 5,866,490 utilizes a pitch as a binder, the pitch having a high percentage of fixed carbon, as well as a high softening point. This is done in an effort to increase carbon bonding in order to prevent corrosion and spalling of the refractory.
  • this reference also teaches the use of a phenol resin or a carbon fiber in addition to the pitch binder.
  • coal tar pitch is a very toxic material, and when the material is heated, the toxic vapors can be released into the atmosphere. This requires the use of expensive safety equipment for those people working near the refractory material, as well as environmental safeguards to prevent the release of the toxic material into the air. Further, coal tar pitch is a known carcinogen, and therefore elimination of the material is generally desirable.
  • monolithic refractory material having good corrosion resistance and spalling resistance, but without the use of a coal tar pitch-based binder. Summary of the invention. [0007] In order to achieve the listed objectives, monolithic refractory material is provided in accordance with the present invention.
  • the refractory material comprises refractory aggregate and a binder, the binder comprising petroleum pitch and carbon black.
  • the binder may further comprise graphite.
  • a monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch.
  • the refractory aggregate comprises brown fused alumina and silicon carbide
  • the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%.
  • the carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black.
  • a monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch, the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%, and the carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black.
  • FIG. 1 is a graphical comparison of carbon retention with refractories utilizing coal tar pitch and petroleum pitch, with and without added carbon black. Detailed description of the preferred embodiments.
  • the present invention is a monolithic refractory comprising a refractory aggregate and a binder, the binder comprising petroleum pitch and carbon black.
  • the refractory may further comprise a dispersant.
  • the refractory comprises about 1.0 to about 3.0% petroleum pitch, about 0.5% to about 1.5% carbon black, with the balance being a refractory aggregate.
  • the refractory may also contain graphite to further increase the carbon content.
  • the refractory further comprises about 0.0 % to about 0.15% of a dispersant.
  • the refractory aggregate used in accordance with the present invention may be any one of the refractory aggregates known by those in the art to be suitable for the present applications.
  • Suitable refractory aggregates include, for example, brown fused alumina, bauxite, tabular alumina, silicon carbide, calcined bauxitic kaolins (such as Mulcoa 70, Mulcoa 60, and Mulcoa 47), andalusite, calcined fireclay, and combinations thereof.
  • the refractory aggregate is present in amounts that depend on the amount of binder desired. However, the refractory aggregate will make up most of the material present in the monolithic refractory.
  • the particle size for the aggregate is based on the principles of optimum particle packing commonly used to formulate ultra low cement castables.
  • the maximum aggregate particle size is about 9.5 millimeters, with a minimum size of about 45 microns.
  • the petroleum pitch used in accordance with the present invention accounts for about 1.0% to about 3.0% of the monolithic refractory.
  • the petroleum pitch is preferably characterized by a mass particle size wherein 50-75%, typically 70% is smaller than about 75 micrometers.
  • the petroleum pitch is also characterized by a carbon yield. Carbon yield is defined as the percent by weight of the pitch that is left as a carbonized residue after the pitch is heated under non-oxidizing conditions to about 800-1000°C to drive off volatiles.
  • the petroleum pitches used may have a carbon yield of about 45% to about 55%.
  • the petroleum pitch is characterized by a carbon yield of about 49%.
  • the carbon black used in accordance with the present invention accounts for about 0.5% to about 1.5% of the monolithic refractory.
  • the carbon black has an average particle size of about 200 nanometers to about 400 nanometers.
  • the carbon black has an average particle size of about 300 nanometers.
  • the carbon black is also characterized by an ash content of less than about 0.25% of the mass of the carbon black. It should be noted that as the amount of carbon black used increases, the amount of water that must be included also increases. This may limit the amount of carbon black that can be incorporated into the monolithic refractory. Graphite may be added to increase the carbon level beyond the limit for carbon black alone.
  • the monolithic refractory may further comprise a dispersant. If used, the dispersant accounts for about 0.01 % to about 0.15% of the monolithic refractory.
  • Suitable dispersants include sodium lignosulfonate, other lignosulfonate salts (Ca, K, etc.), or Sodium, potassium and Calcium salts of condensed naphthalene sulfonic acids.
  • a wet sprayable refractory comprising brown fused alumina, silicon carbide, calcium aluminate cement, petroleum pitch, carbon black and a sodium lignosulfonate dispersant powder.
  • the petroleum pitch was a pitch commercially available under the name "Trolumen” from Smith-Facing of Cleveland, OH, having 70% finer than 75 micrometers and
  • the pitch made up 2.33% of the refractory.
  • the carbon black made up 1 % of the refractory and is available from Asbury Carbon of Asbury, NJ, and sold as #5991.
  • the sodium lignosulfonate dispersant powder made up 0.05% of the refractory and is available from Lignotech of Rothschild, Wl under the name "Ultrazine NA.”
  • the balance of the refractory was the aggregate (brown fused alumina, silicon carbide and calcium aluminate cement).
  • the refractory was subjected to 1500° F for 5 hours, along with a similar refractory containing coal tar pitch instead of petroleum pitch, a similar refractory without carbon black, and a refractory without carbon black and with coal tar pitch instead of petroleum pitch, in the same amount.
  • the carbon retention was measured for all 4 refractories. As illustrated in Fig. 1 , the % carbon retention for the two refractories with petroleum pitch, while lower, was acceptably similar to the two refractories using coal tar pitch. Further, the refractories utilizing the carbon black had higher carbon retention than the two without the carbon black.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Thermal Sciences (AREA)
  • Ceramic Products (AREA)

Abstract

A monolithic refractory material is provided. The refractory material comprises refractory aggregate and a binder, the binder comprising petroleum pitch and carbon black. Advantageously, the binder may further comprise graphite.

Description

Monolithic Castable Refractory. Specification.
Cross-reference to related applications. [0001] This application claims the benefit under 35 U.S.C. §120 of the filing date of U.S. Provisional Application No. 60/530,831 filed December 18, 2003. Field of the invention.
[0002] The present invention relates to monolithic refractory materials, and in particular a low- toxicity castable refractory having excellent corrosion resistance and spalling resistance. Description of the related art.
[0003] In the processing and handling of molten metals, monolithic refractory materials are often used as linings for vessels such as ladles that transport the molten metal throughout the process. In order to help prevent corrosion and spalling of the refractory, carbon-bonded materials are typically used. The monolithic refractories generally comprise a refractory aggregate and a binder. Various binders have been used throughout the years, including binders utilizing coal tar pitch.
[0004] For example, U.S. Patent No. 4,184,883 discloses a pitch-bonded refractory that utilizes a cure accelerator such as calcium nitrate to accelerate the rate of increase of the softening point of the pitch in order to decrease the amount of spalling that occurs during burn-in and the early heats of the refractory. U.S. Patent No. 5,866,490 utilizes a pitch as a binder, the pitch having a high percentage of fixed carbon, as well as a high softening point. This is done in an effort to increase carbon bonding in order to prevent corrosion and spalling of the refractory. To this end, this reference also teaches the use of a phenol resin or a carbon fiber in addition to the pitch binder. [0005] A common problem with the use of coal tar pitch is that it is a very toxic material, and when the material is heated, the toxic vapors can be released into the atmosphere. This requires the use of expensive safety equipment for those people working near the refractory material, as well as environmental safeguards to prevent the release of the toxic material into the air. Further, coal tar pitch is a known carcinogen, and therefore elimination of the material is generally desirable.
[0006] It is therefore desirable to produce a monolithic refractory material having good corrosion resistance and spalling resistance, but without the use of a coal tar pitch-based binder. Summary of the invention. [0007] In order to achieve the listed objectives, monolithic refractory material is provided in accordance with the present invention. The refractory material comprises refractory aggregate and a binder, the binder comprising petroleum pitch and carbon black. Advantageously, the binder may further comprise graphite.
[0008] Also provided in accordance with the present invention is a monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch. The refractory aggregate comprises brown fused alumina and silicon carbide, the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%. The carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black.
[0009] Further provided in accordance with the present invention is a monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch, the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%, and the carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black. Brief description of the several drawings.
[0010] FIG. 1 is a graphical comparison of carbon retention with refractories utilizing coal tar pitch and petroleum pitch, with and without added carbon black. Detailed description of the preferred embodiments.
[0011] Except where otherwise noted, all percentages listed below, including in the claims, are on a weight basis and are a percentage of the monolithic refractory. The present invention is a monolithic refractory comprising a refractory aggregate and a binder, the binder comprising petroleum pitch and carbon black. The refractory may further comprise a dispersant. The refractory comprises about 1.0 to about 3.0% petroleum pitch, about 0.5% to about 1.5% carbon black, with the balance being a refractory aggregate. The refractory may also contain graphite to further increase the carbon content. Preferably, the refractory further comprises about 0.0 % to about 0.15% of a dispersant. [0012] The refractory aggregate used in accordance with the present invention may be any one of the refractory aggregates known by those in the art to be suitable for the present applications. Suitable refractory aggregates include, for example, brown fused alumina, bauxite, tabular alumina, silicon carbide, calcined bauxitic kaolins (such as Mulcoa 70, Mulcoa 60, and Mulcoa 47), andalusite, calcined fireclay, and combinations thereof. The refractory aggregate is present in amounts that depend on the amount of binder desired. However, the refractory aggregate will make up most of the material present in the monolithic refractory. The particle size for the aggregate is based on the principles of optimum particle packing commonly used to formulate ultra low cement castables. The maximum aggregate particle size is about 9.5 millimeters, with a minimum size of about 45 microns. [0013] The petroleum pitch used in accordance with the present invention accounts for about 1.0% to about 3.0% of the monolithic refractory. The petroleum pitch is preferably characterized by a mass particle size wherein 50-75%, typically 70% is smaller than about 75 micrometers. The petroleum pitch is also characterized by a carbon yield. Carbon yield is defined as the percent by weight of the pitch that is left as a carbonized residue after the pitch is heated under non-oxidizing conditions to about 800-1000°C to drive off volatiles. The petroleum pitches used may have a carbon yield of about 45% to about 55%. Preferably, the petroleum pitch is characterized by a carbon yield of about 49%.
[0014] The carbon black used in accordance with the present invention accounts for about 0.5% to about 1.5% of the monolithic refractory. The carbon black has an average particle size of about 200 nanometers to about 400 nanometers. Preferably, the carbon black has an average particle size of about 300 nanometers. The carbon black is also characterized by an ash content of less than about 0.25% of the mass of the carbon black. It should be noted that as the amount of carbon black used increases, the amount of water that must be included also increases. This may limit the amount of carbon black that can be incorporated into the monolithic refractory. Graphite may be added to increase the carbon level beyond the limit for carbon black alone.
[0015] The monolithic refractory may further comprise a dispersant. If used, the dispersant accounts for about 0.01 % to about 0.15% of the monolithic refractory. Suitable dispersants include sodium lignosulfonate, other lignosulfonate salts (Ca, K, etc.), or Sodium, potassium and Calcium salts of condensed naphthalene sulfonic acids. Example
[0016] A wet sprayable refractory was produced comprising brown fused alumina, silicon carbide, calcium aluminate cement, petroleum pitch, carbon black and a sodium lignosulfonate dispersant powder. The petroleum pitch was a pitch commercially available under the name "Trolumen" from Smith-Facing of Cleveland, OH, having 70% finer than 75 micrometers and
49% carbon yield. The pitch made up 2.33% of the refractory. The carbon black made up 1 % of the refractory and is available from Asbury Carbon of Asbury, NJ, and sold as #5991. The sodium lignosulfonate dispersant powder made up 0.05% of the refractory and is available from Lignotech of Rothschild, Wl under the name "Ultrazine NA." The balance of the refractory was the aggregate (brown fused alumina, silicon carbide and calcium aluminate cement). The refractory was subjected to 1500° F for 5 hours, along with a similar refractory containing coal tar pitch instead of petroleum pitch, a similar refractory without carbon black, and a refractory without carbon black and with coal tar pitch instead of petroleum pitch, in the same amount. The carbon retention was measured for all 4 refractories. As illustrated in Fig. 1 , the % carbon retention for the two refractories with petroleum pitch, while lower, was acceptably similar to the two refractories using coal tar pitch. Further, the refractories utilizing the carbon black had higher carbon retention than the two without the carbon black.
[0017] Obviously, numerous modifications and variations of the present invention are possible. It is, therefore, to be understood that within the scope of the following claims, the invention may be practiced otherwise than as specifically described.

Claims

Claims.We claim:
1. A monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch.
2. The monolithic refractory material of claim 1 , wherein the refractory aggregate is selected from the group consisting of brown fused alumina, bauxite, tabular alumina, silicon carbide, calcined bauxitic kaolins, andalusite, and calcined fireclay and combinations thereof.
3. The monolithic refractory material of claims 1 to 2, characterized in that the refractory aggregate has a maximum particle size of about 45 microns to about 9.5 millimeters.
4. The monolithic refractory material of claims 1 to 3, characterized in that the refractory material comprises about 1.0 % to about 3.0% petroleum pitch.
5. The monolithic refractory material of claims 1 to 3, characterized in that the refractory material comprises about 2.3% petroleum pitch.
6. The monolithic refractory material of claims 1 to 3, characterized in that the refractory material comprises about 0.5% to about 1.5% carbon black
7. The monolithic refractory material of claims 1 to 3, characterized in that the refractory material comprises about 1.0% carbon black.
8. The monolithic refractory material of claims 1 to 7, further comprising a dispersant.
9. The monolithic refractory material of claim 8, characterized in that the dispersant is selected from the group consisting of sodium lignosulfonate, calcium lignosulfonate salt, potassium lignosulfonate salt, and sodium, potassium and calcium salts of condensed naphthalene sulfonic acids.
10. The monolithic refractory material of claims 8 to 9, characterized in that the dispersant comprises sodium lignosulfonate.
11. The monolithic refractory material of claims 8 to 10, characterized in that the refractory material comprises about 0.01 % to about 0.15% of a dispersant.
12. The monolithic refractory material of claims 8 to 10, characterized in that the refractory material comprises about 0.05% of a dispersant.
13. The monolithic refractory material of claims 1 to 12, characterized in that the carbon black has an average particle size of about 200 nanometers to about 400 nanometers.
14. The monolithic refractory material of claims 1 to 12 characterized in that the carbon black has an average particle size of about 300 nanometers.
15. The monolithic refractory material of claims 1 to 14, characterized in that the carbon black has an ash content of less than about 0.25% of the mass of the carbon black.
16. The monolithic refractory material of claims 1 to 15, characterized in that the petroleum pitch has a mass particle size wherein about 50 to about 75% is smaller than about 75 micrometers.
17. The monolithic refractory material of claims 1 to 16, characterized in that the binder further comprises graphite.
18. A monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch, the refractory aggregate comprises brown fused alumina and silicon carbide, the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%, and the carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black.
19. The monolithic refractory material of claim 18, characterized in that the refractory aggregate has a maximum particle size of about 45 microns to about 9.5 millimeters.
20. The monolithic refractory material of claim 18, wherein the petroleum pitch has a carbon yield of about 49%.
21. The monolithic refractory material of claims 18 to 20, further comprising a dispersant.
22. The monolithic refractory material of claim 21 , characterized in that the dispersant is selected from the group consisting of sodium lignosulfonate, calcium lignosulfonate salt, potassium lignosulfonate salt, and sodium, potassium and calcium salts of condensed naphthalene sulfonic acids.
23. The monolithic refractory material of claims 21 to 22, characterized in that the dispersant comprises sodium lignosulfonate.
24. The monolithic refractory material of claims 21 to 23, characterized in that the refractory material comprises about 0.01% to about 0.15% of a dispersant.
25. The monolithic refractory material of claims 21 to 23, characterized in that the refractory material comprises about 0.05% of a dispersant.
26. The monolithic refractory material of claims 18 to 25, characterized in that the binder further comprises graphite.
27. A monolithic refractory material comprising a refractory aggregate and a binder, characterized in that the binder comprises carbon black and petroleum pitch, the petroleum pitch has a mass particle size wherein 50 to 70% is smaller than 75 micrometers and has a carbon yield of about 45% to about 55%, and the carbon black has an average particle size of about 200 nanometers to about 400 nanometers and an ash content of less than about 0.25% of the mass of the carbon black.
28. The monolithic refractory material of claim 27, wherein the refractory aggregate is selected from the group consisting of brown fused alumina, bauxite, tabular alumina, silicon carbide, calcined bauxitic kaolins, andalusite, calcium aluminate cement and calcined fireclay and combinations thereof.
29. The monolithic refractory material of claims 27 to 28, characterized in that the refractory aggregate has a maximum particle size of about 45 microns to about 9.5 millimeters.
30. The monolithic refractory material of claims 27 to 28, wherein the petroleum pitch has a carbon yield of about 49%.
31. The monolithic refractory material of claims 27 to 30, further comprising a dispersant.
32. The monolithic refractory material of claim 31 , characterized in that the dispersant is selected from the group consisting of sodium lignosulfonate, calcium lignosulfonate salt, potassium lignosulfonate salt, and sodium, potassium and calcium salts of condensed naphthalene sulfonic acids.
33. The monolithic refractory material of claims 31 to 32, characterized in that the dispersant comprises sodium lignosulfonate.
34. The monolithic refractory material of claims 31 to 33, characterized in that the refractory material comprises about 0.01 % to about 0.15% of a dispersant.
35. The monolithic refractory material of claims 31 to 34, characterized in that the refractory material comprises about 0.05% of a dispersant.
36. The monolithic refractory material of claims 27 to 35, characterized in that the binder further comprises graphite.
PCT/US2004/042861 2003-12-18 2004-12-17 Monolithic castable refractory Ceased WO2005061411A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US53083103P 2003-12-18 2003-12-18
US60/530,831 2003-12-18

Publications (1)

Publication Number Publication Date
WO2005061411A1 true WO2005061411A1 (en) 2005-07-07

Family

ID=34710180

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2004/042861 Ceased WO2005061411A1 (en) 2003-12-18 2004-12-17 Monolithic castable refractory

Country Status (1)

Country Link
WO (1) WO2005061411A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8026191B2 (en) * 2007-01-26 2011-09-27 Wonjin Worldwide Co., Ltd. Carbon-containing refractory composition containing no resinous binder
CN102826862A (en) * 2012-09-04 2012-12-19 山西新型炉业集团有限公司 Raw material proportion and producing method for bauxite-based dense homogenized grog
CN108821784A (en) * 2018-06-19 2018-11-16 佘春霞 A kind of high carbon black environmental protection castable in main trough

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4071593A (en) * 1973-11-06 1978-01-31 General Refractories Company Process for making a pitch impregnated, cold molded refractory article
US4184883A (en) * 1976-12-17 1980-01-22 Eltra Corporation Pitch bonded refractory
US4521357A (en) * 1983-05-02 1985-06-04 Dresser Industries, Inc. Carbon bonded refractories
US4558019A (en) * 1984-01-20 1985-12-10 Allied Corporation Periclase refractory brick with oxyhydrocarbon component
US4585485A (en) * 1983-01-24 1986-04-29 Hiroshi Shikano Refractory sliding nozzle plate
US4605635A (en) * 1984-01-17 1986-08-12 Shinagawa Refractories Co., Ltd. Carbon-containing refractory
US5304225A (en) * 1990-05-15 1994-04-19 Rutgerswerke Ag Binder mixture
US5346942A (en) * 1989-10-11 1994-09-13 Shinagawa Refractories Co., Ltd. Monolithic refractories
US6288001B1 (en) * 1997-12-25 2001-09-11 Kawasaki Steel Corporation Graphite-containing monolithic refractory material

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4071593A (en) * 1973-11-06 1978-01-31 General Refractories Company Process for making a pitch impregnated, cold molded refractory article
US4184883A (en) * 1976-12-17 1980-01-22 Eltra Corporation Pitch bonded refractory
US4585485A (en) * 1983-01-24 1986-04-29 Hiroshi Shikano Refractory sliding nozzle plate
US4521357A (en) * 1983-05-02 1985-06-04 Dresser Industries, Inc. Carbon bonded refractories
US4605635A (en) * 1984-01-17 1986-08-12 Shinagawa Refractories Co., Ltd. Carbon-containing refractory
US4558019A (en) * 1984-01-20 1985-12-10 Allied Corporation Periclase refractory brick with oxyhydrocarbon component
US5346942A (en) * 1989-10-11 1994-09-13 Shinagawa Refractories Co., Ltd. Monolithic refractories
US5304225A (en) * 1990-05-15 1994-04-19 Rutgerswerke Ag Binder mixture
US6288001B1 (en) * 1997-12-25 2001-09-11 Kawasaki Steel Corporation Graphite-containing monolithic refractory material

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8026191B2 (en) * 2007-01-26 2011-09-27 Wonjin Worldwide Co., Ltd. Carbon-containing refractory composition containing no resinous binder
CN102826862A (en) * 2012-09-04 2012-12-19 山西新型炉业集团有限公司 Raw material proportion and producing method for bauxite-based dense homogenized grog
CN108821784A (en) * 2018-06-19 2018-11-16 佘春霞 A kind of high carbon black environmental protection castable in main trough

Similar Documents

Publication Publication Date Title
AU2009229913A1 (en) Plate brick and manufacturing method therefor
US4208214A (en) Refractory compositions
EP0429168B1 (en) Ramming composition
WO2005061411A1 (en) Monolithic castable refractory
JP2617086B2 (en) Silicon carbide casting material
JPS58125660A (en) Sliding-nozzle-plate having high durability
WO2011079090A2 (en) Chromia-containing refractory
JP2743209B2 (en) Carbon containing refractories
CA2143169A1 (en) Resin bonded ceramic, carbon metal composite comprising boron source and a combination of at least two metals
JP2005139062A (en) Low carbon unfired brick
KR100723131B1 (en) High corrosion resistance fireproof composition for closing blast furnace exit
EP1138646A1 (en) Carbonaceous refractory with high resistance to spalling and process for producing the same
JP3906500B2 (en) Method for producing binder for carbon-containing refractory
JP2596700B2 (en) Specific carbon-containing irregular refractories
JP4571522B2 (en) Conductive amorphous refractories for DC electric furnace hearth stamp construction
JP2004141899A (en) Sliding nozzle plate for ladle
KR100293186B1 (en) Zirconium diboride sintering material excellent in corrosion resistance and thermal shock resistance
JPH1017357A (en) Production of carbon-containing refractory
JP2025152511A (en) Method of producing plate brick
JP2947385B2 (en) Carbon containing refractories
JPH06263523A (en) Production of carbon-containing unburned brick
WO2024150669A1 (en) Production method for magnesia-carbon brick
JP2001146464A (en) Refractory containing massive graphite
JPS59107961A (en) Carbon-containing refractories
JP3878244B2 (en) Method for producing carbon-containing refractories

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 KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL 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 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
DPEN Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Country of ref document: DE

122 Ep: pct application non-entry in european phase