Classifications

• • 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
  • C10B53/00—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form
  • C10B53/08—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form in the form of briquettes, lumps and the like

Definitions

• the present invention relates to a process for manufacturing metallurgical coke of good quality, from coke pastes in which the so-called coking coals have been replaced, in whole or in part, by so-called low or non-coking coals.
• metallurgical coke which can be used in particular as a feedstock for blast furnaces, is generally manufactured by charging raw materials, mainly so-called coking coal, in carbonization cells and by heating these materials which, by distillation and agglutination, give a product having the well known properties of coke used in steel plants.
• the generally used carbonization cells are made of refractory bricks and are heated externally by hot fumes. These carbonization cells do not are never completely waterproof. Consequently, in order to avoid any entry of air into the ovens, while limiting gas losses to the outside, the pressure of the distillation gases must be constantly maintained at a value slightly higher than atmospheric pressure (overpressure of a few millimeters of water column).
• the material used in conventional metallurgical coke manufacturing processes is generally used in the pulverulent state, which has the well-known drawbacks of such a state from the point of view of atmospheric pollution and the healthiness of the material. work to which staff are assigned.
• the manufacture of metallurgical coke according to conventional methods is carried out in an extremely rigid framework with the possibility of action on a very limited number of parameters.
• the manufacture of coke according to the conventional process can only be done from certain so-called coking coals having good properties. determined.
• These coals are becoming increasingly rare, their cost increases and the cost price of coke produced from these coals increases.
• the reduction in the supply of so-called coking coals can make it difficult, if not impossible, to regularly supply production facilities.
• the process which is the subject of the present invention is essentially characterized in that after having prepared the coke paste by one or more of the following operations: grinding, drying, preheating and addition of a binder-solvent, this coke paste is subjected to compacting in a selected form, preferably followed by surface cooking, then to coking under a gas pressure substantially higher than atmospheric pressure, by means of the distillation gases which are preferably recycled and drawn through the aggregate bed and whose temperature and pressure are maintained at adequate predetermined values, and finally by extinction of the coke thus obtained.
• the possible forms are as follows: balls (ovoids, spheroids, pads, bananas, orange wedges, horse saddles etc.), splits, granules, etc. Preference is given to shapes which give a high vacuum index to the bulk material after compaction.
• the necessary heat supply is ensured by bringing the distillation gases to high temperature in an external heat exchanger before their recycling and their pulsation through the bed of aggregates.
• the gas pressure in the enclosure is maintained at the appropriate value depending in particular on the nature of the coal and the quality of coke sought.
• the coking operation is carried out in two stages, the first of which with circulation of low-quality distillation gases, that is to say containing various products, which may or may not be harmful, such as for example tar, benzol, etc. These latter products are preferably extracted from the distillation gases before their recycling which takes place after reheating and partial evacuation.
• the second step we circulate gases noble distillation, that is to say rich in H 2 and CO. With such gases, the fraction recycled after reheating does not require any purification treatment, while the fraction removed to maintain the pressure at an adequate value can be used in particular as synthesis gas for the chemical industry.
• coke quenching operation it can be carried out wet with water or dry (gas).
• this operation can be carried out following the second coking step, by means of an inert gas from which the therms are preferably recovered to carry out other phases of the process such only drying, preheating, external cooking and coking.
• a first part of the dry extinction is carried out by means of distillation gases produced during the first stage of the coking operation, as follows: these gases, preferably purified, heat up on the incandescent coke before being recycled and transfer the accumulated heat to the aggregates being carbonized.
• the carbon intended for coking must be at an adequate particle size, always less than 10 mm, preferably less than 5 mm, and all the finer that said carbon contains inert materials.
• the carbon is dried using one of the many known methods (rotary kiln, fluidized bed, multitubular dryer, etc.).
• the coal is then preheated to a temperature below its softening temperature.
• the coal is then intimately mixed with a suitable solvent-binder such as, for example: coal pitch, petroleum pitch, tar, bitumen, oils, etc. . .
• a suitable solvent-binder such as, for example: coal pitch, petroleum pitch, tar, bitumen, oils, etc. . .
• This solvent-binder is preferably injected in liquid form, in order to obtain good dispersion in the mass.
• the compacted aggregates are baked superficially in an atmosphere at high temperature (above 500 ° C.) so that only their external surface layer is brought to a temperature higher than the softening temperature of the coal.
• high temperature above 500 ° C.
• the purpose of this cooking is to avoid any subsequent agglutination of the aggregates formed.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Coke Industry (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=19729616

Family Applications (1)

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Cited By (1)

Family Cites Families (5)

• 1981
  • 1981-03-27 LU LU83261A patent/LU83261A1/fr unknown
• 1982
  • 1982-03-24 BE BE6/47626A patent/BE892631A/fr not_active IP Right Cessation
  • 1982-03-25 JP JP50114882A patent/JPS58500484A/ja active Pending
  • 1982-03-25 WO PCT/BE1982/000005 patent/WO1982003403A1/en not_active Application Discontinuation
  • 1982-03-25 EP EP19820900927 patent/EP0074977A1/de not_active Withdrawn

Non-Patent Citations (1)

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