WebCPC CPC COOPERATIVE PATENT CLASSIFICATION

C21B　MANUFACTURE OF IRON OR STEEL (preliminary treatment of ferrous ores or scrap C22B 1/00; electric heating H05B)

C21B 3/00 General features in the manufacture of pig-iron (mixers for pig-iron C21C 1/06)

C21B 3/02 ・by applying additives, e.g. fluxing agents

C21B 3/04 ・Recovery of by-products, e.g. slag

C21B 3/06 ・・Treatment of liquid slag (slag wool C03B; slag stones C04B)

C21B 3/08 ・・・Cooling slag

C21B 3/10 ・・・Slag pots; Slag cars

C21B 5/00 Making pig-iron in the blast furnace

C21B 5/001 ・{Injecting additional fuel or reducing agents}

C21B 5/002 ・・{Heated electrically (plasma)}

C21B 5/003 ・・{Injection of pulverulent coal}

C21B 5/004 ・・・{Injection of slurries}

C21B 5/006 ・{Automatically controlling the process}

C21B 5/007 ・{Conditions of the cokes or characterised by the cokes used}

C21B 5/008 ・{Composition or distribution of the charge}

C21B 5/02 ・Making special pig-iron, e.g. by applying additives, e.g. oxides of other metals

C21B 5/023 ・・{Injection of the additives into the melting part}

C21B 5/026 ・・・{of plastic material}

C21B 5/04 ・Making slag of special composition

C21B 5/06 ・Using top gas in the blast furnace process (in coke ovens C10B)

C21B 7/00 Blast furnaces (lifts associated with blast furnaces B66B 9/06)

C21B 7/002 ・{Evacuating and treating of exhaust gases}

C21B 7/005 ・・{Bleeder valves or slides}

C21B 7/007 ・{Controlling or regulating of the top pressure}

C21B 7/02 ・Internal forms

C21B 7/04 ・with special refractories (refractory materials C04B)

C21B 7/06 ・・Linings for furnaces

C21B 7/08 ・Top armourings

C21B 7/10 ・Cooling; Devices therefor

C21B 7/103 ・・{Detection of leakages of the cooling liquid}

C21B 7/106 ・・{Cooling of the furnace bottom}

C21B 7/12 ・Opening or sealing the tap holes

C21B 7/125 ・・{Refractory plugging mass}

C21B 7/14 ・Discharging devices, e.g. for slag

C21B 7/16 ・Tuyeres

C21B 7/163 ・・{Blowpipe assembly}

C21B 7/166 ・・{Tuyere replacement apparatus}

C21B 7/18 ・Bell-and-hopper arrangements

C21B 7/20 ・・with appliances for distributing the burden

C21B 7/22 ・Dust arresters

C21B 7/24 ・Test rods or other checking devices

C21B 9/00 Stoves for heating the blast in blast furnaces

C21B 9/02 ・Brick hot-blast stoves

C21B 9/04 ・・with combustion shaft

C21B 9/06 ・・Linings

C21B 9/08 ・Iron hot-blast stoves

C21B 9/10 ・Other details, e.g. blast mains

C21B 9/12 ・・Hot-blast valves or slides for blast furnaces (valves in general F16K)

C21B 9/14 ・Preheating the combustion air

C21B 9/16 ・Cooling or drying the hot-blast

C21B 11/00 Making pig-iron other than in blast furnaces

C21B 11/02 ・in low shaft furnaces {or shaft furnaces}

C21B 11/06 ・in rotary kilns

C21B 11/08 ・in hearth-type furnaces

C21B 11/10 ・in electric furnaces

C21B 13/00 Making spongy iron or liquid steel, by direct processes

C21B 13/0006 ・{obtaining iron or steel in a molten state}

C21B 13/0013 ・・{introduction of iron oxide into a bath of molten iron containing a carbon reductant}

C21B 13/002 ・・・{Reduction of iron ores by passing through a heated column of carbon}

C21B 13/0026 ・・{introduction of iron oxide in the flame of a burner or a hot gas stream}

C21B 13/0033 ・{In fluidised bed furnaces or apparatus containing a dispersion of the material}

C21B 13/004 ・{in a continuous way by reduction from ores}

C21B 13/0046 ・{making metallised agglomerates or iron oxide}

C21B 13/0053 ・・{On a massing grate}

C21B 13/006 ・{Starting from ores containing non ferrous metallic oxides}

C21B 13/0066 ・{Preliminary conditioning of the solid carbonaceous reductant}

C21B 13/0073 ・{Selection or treatment of the reducing gases}

C21B 13/008 ・{Use of special additives or fluxing agents}

C21B 13/0086 ・{Conditioning, transformation of reduced iron ores}

C21B 13/0093 ・・{Protecting against oxidation}

C21B 13/02 ・in shaft furnaces

C21B 13/023 ・・{wherein iron or steel is obtained in a molten state}

C21B 13/026 ・・・{heated electrically}

C21B 13/04 ・in retorts

C21B 13/06 ・in multi-storied furnaces

C21B 13/08 ・in rotary furnaces

C21B 13/085 ・・{wherein iron or steel is obtained in a molten state}

C21B 13/10 ・in hearth-type furnaces

C21B 13/105 ・・{Rotary hearth-type furnaces}

C21B 13/12 ・in electric furnaces

C21B 13/125 ・・{By using plasma}

C21B 13/14 ・Multi-stage processes {processes carried out in different vessels or furnaces}

C21B 13/143 ・・{Injection of partially reduced ore into a molten bath}

C21B 13/146 ・・{Multi-step reduction without melting}

C21B 15/00 Other processes for the manufacture of iron from iron compounds (general methods of reducing to metal C22B 5/00; by electrolysis C25C 1/06)

C21B 15/003 ・{By using nuclear energy}

C21B 15/006 ・{By a chloride process}

C21B 15/02 ・Metallothermic processes, e.g. thermit reduction

C21B 15/04 ・from iron carbonyl

C21B 2005/00 Making pig-iron in the blast furnace

C21B 2005/001 ・{Injecting additional fuel or reducing agents}

C21B 2005/005 ・・Selection or treatment of the reducing gases

C21B 2100/00 Exhaust gases

C21B 2100/02 ・Treatment of the exhaust gases

C21B 2100/04 ・Recirculation of the exhaust gases

C21B 2100/06 ・Energy from waste gases used in other processes

C21B 2200/00 Recycling of waste material

C21B 2300/00 Process aspects

C21B 2300/02 ・Particular sequence of the process steps

C21B 2300/04 ・Modeling of the process, e.g. for control purposes; CII