SU976856A3 - Method of producing metallic melt from ground iron ore material - Google Patents

Description

397 al easily acquires a consistency that makes it difficult to recover the material during the subsequent treatment process. Serious mechanical problems arise when unloading such a compact compact material from the lower part of the mine, since the sintered material after cooling acquires a pseudo-NOLITE character, i.e. behaves like a monolithic material while being a sintering product. The most amphibious and technical result and the achieved result is a method of obtaining a metallic melt from crushed material, including its loading into the furnace, partial reduction with gaseous combustion products and subsequent final conversion with carbon L33. According to a known method, a pure CO-rich gas is used, Koioporo expels soot and precipitates on a material consisting of iron oxides, at relatively low temperatures UOO-60O ° C) The resulting partially reduced product still contains 80-85% of the original amount of oxygen in the original raw material The main part of the recovery process is carried out at the next high-temperature stage, because of the low degree of reduction achieved at the nepBdro recovery stage, a significant amount of energy is required. The goal of the Internet is to intensify the process. The goal is achieved by the method of producing a metal melt from crushed iron ore material, including loading it into a furnace, partially reducing combustion gases with gaseous products and subsequent final reduction with carbon, partially reducing the molten by tangential iron supply of the material, solid carbon fraction. and oxygen-containing, pelvis in the fired combustion, and the re-recovery is carried out by residual solid recovery novelty, present in the molten material. Full or partial use of sulphide Qbjpfbfl for the production of a portion of the recovered product is envisaged. FIG. 1 shows schematically an installation for implementing the method; in 564 of FIG. 2 and 3 are two variants of modified mine structures, Installation: consists of a mine or colo1, in which iron oxide melts and is partially reduced. The lower part of the shaft 1 enters directly into the reactor zone 2, in which the partially reduced iron oxide is finally reduced and melted to form molten iron. The gases generated together with some of the dust and evaporated or gasified components of the loaded materials are removed from the upper, outlet pipe, which allows for the adaptation of these gases and the attraction of heat contained in them. these devices contain a steam boiler 4, a cyclone device 5 and a gas purification device 6, designed, for example, for a wet gas cleaning system, from which the purified gases (most of the heat contained in them is removed) are led through a pipe 7 to a dash pipe. The upper part of the mine is 1 "the pipeline of exhaust gases is above the metal pipes through which the boiling water is circulating. For convenience, the exhaust gas pipeline 3 is equipped with devices for cleaning the lined pipe walls from deposits. The protective coating can be made of iron oxide material, frozen on the walls of the shaft, equipped with pipes. These walls can be provided with studs or pins inserted into the wall to facilitate freezing of the molten material. The steam formed in the pipes is separated along with the steam of the steam boiler 4 in the bell 8, from which the separated steam pipe is passed through, lines 9 and 10 to the condenser turbine 11 forming part of the boiler 4 that is not passed through the turbine. The steam passed through the turbine condenses. -team 12 and condensate produced in the cooler, discharged through conduit 13, may be returned to boiler 4. When low pressure steam or hot water is required for another use, turbine 11 may be replaced by a counter-pressure turbine. In the roof of mine 1 there is a colde of burners 14 for supplying finely divided iron oxide, coal or other carbonaceous or carbon containing reducing reagent to mine 1. limestone and / or other slagworkers or flux, returnable dust from the steam boiler 4 and the cyclone device 5, and oxygen or other gas intended for the combustion process, or air or oxygen-enriched air. In this case, the oxygen-containing gas supplied to the cavity 14 is obtained at the oxygen-gas production unit 15, KOfTopyro is supplied with compressed air from the compressor 16 driven by the turbine 11. The compressor 16 is provided with pipes for air inlet 17 and air outlet 18. Iron oxide, limestone, return dust accumulate in bins 19-22, from which they are drawn in proper proportions and loaded into a mixing and balancing 23 using a conveyor belt 24. This mixture

materials are fed from hopper 24 to burners 14 through lines 25 and 26. Oxygen gas is supplied to burners through lines 27 and 28, from which it enters pipelines 26.

Burners 14, of which two are shown in FIG. 1) directed obliquely downward and tangential to an imaginary circle in the lower part of the shaft 1. The diameter of this imaginary circle; About a quarter of the diameter of the shaft, and the location and angle of the burners are such that the material ejected from them is directed to the periphery of the imaginary circle in the region x, arranged symmetrically in a circle. An additional oxygen-containing gas for the final incineration of the material is supplied to the upper part of the shaft 1 through horizontal nozzles 29, which are fed from the pipeline 2.7, from -. branch from the pipeline 30. The nozzles 29 are tangentially oriented mainly to ensure that the oxygen gas flows from them are tangential to an imaginary circle whose diameter is about a third of the diameter of the shaft.

During its passage from the burners 14 down the shaft 1, the iron oxide melts and partially recovers, the coal is converted to coke, and the limestone burns out. Return dust, consisting mainly of iron oxide, melts and is partially reduced. The molten and partially reduced iron oxide together with coke and burnt limestone reaches the upper surface of the layer of the reactor material.

By cutting the coke layer, the elsez content in the molten slag is lowered, silicon is formed when reduced, and the molten iron that is formed becomes carbonized.

The energy required to melt and finally reduce the iron oxide is supplied to the reactor zone 2 by electro-induction heating of the material contained therein. For this purpose, an induction coil 32 is installed around the reactor zone 2, supplied with alternating current from the generator 33 through the converter 34.

With such induction heating, the energy generated per unit volume in the material layer increases from the center of the reactor zone to its periphery. Accordingly, the material that is loaded into the layer will move down nationally and outwards during the ongoing reduction of iron oxide and melting (Fig. 1)

The dust mainly consisting of iron oxide is separated in boiler 4 and cyclone device 5. This dust is conveyed to conveyor belts 35 and 36 and passed through devices (not shown) to one of the hoppers 19 22, which is used for storing returnable dust. The metals emitted from the material during the process, such as lead and zinc in the form of fine-grained oxides and solid trioxide, in vapor form, pass through the steam boiler 4. And cyclone device 5 and are separated. In solid form in the gas cleaning device 3. Planted in the gas cleaning unit 6 dust is removed by the pipeline 37 for separate treatment and such zones located in the lower part of the mine. In the upper zone of the specified layer of material molten iron oxide. reacts with coke to ensure further partial reduction of iron oxide with cooling. The material formed in the layer then acquires a semi-liquid or pasty consistency. The iron remover material is finally reduced and melts in the reactor zone 2 with a further consumption of coke, resulting in the formation of molten iron. The latter is collected together with the molten slag in the lower part of the reactor zone, from where they are withdrawn either continuously or periodically through the outlet device 31. The charging amount of coal is selected so that a layer of coke is maintained on the iron and slag bath. When passing through a pattern, it does not return to bunkers 1922. Produced in the shaft 1, the pipeline 3 OTDOWN 1-1X gases and the steam boiler 4, the steam is used to operate the turbine 11, which, in addition to the compressor-16, also causes the generator, 33, E, to rotate by adjusting the supply of combustible material, energy generated in mine 1 instantaneous melting may be adjusted so that the amount of steam generated in the system is sufficient to cover the energy required for melting and reduction and the dp of equipment 15 for oxygen gas generation. For this plant, which has a capacity of 30 tons of molten lyryria per hour, the full process requires about 59 kg of coal per ton of pig iron with a calorific value of 26.4 GJ / t (6.3 Gcal / t). In this situation, the process becomes self-sustaining in relation to the energy required to melt and reduce oxides of jelly and produce oxygen gas under normal conditions of efficiency at various stages of energy conversion, TaKVBC as a boiler, turbine, generator, converter, etc. Thus, the process is characterized in primary energy in the form of coal, which is only 15.6 GJ (3.7 Gcal) per ton of pig iron. For comparison, the primary energy requirement for a conventional blast furnace process is 18.2 (4.35 Gc tonnes), including coke production. In addition, in the implementation of the proposed method, coal of a much poorer quality than the coal used for the production of blast furnace coke can be used. The shaft shown in FIG. 2 has an upper 38 and lower 39 zones and is part of an installation of the same general type as shown in FIG. 1. but adapted to produce molten pig iron from finely ground pyrite concentrates. The lower part of the shaft is directly merged with the reactor zone, in which the partially reduced iron oxide is finally reduced and melted to form molten iron. The shaft of mine 1 contains a ring of burners 4O that feed finely ground concentrate, limestone and / or other slag former or flux, return dust and oxygen-containing gas 9 568. or some other gases, such as air or oxygen-enriched air, to maintain combustion or roasting. In this embodiment of the device, solid material is passed to burners 40 through pipelines 41 and 42, and oxygen gas is passed through pipelines 43 and pipes 44 and 45 corresponding to pipe 43. The burners (only two are shown) are directed downwards and tangentially to an imaginary circle, the diameter of which is smaller than the smallest size in the cross section of the mine, so that a vortex arises in the mine. movement. Oxygen gas is also supplied to shaft 1 through horizontal injectors 46, which are fed from pipelines 44 through pipelines 47, Response from pipelines 44. These nozzles are directed tangentially so as to maintain the vortex movement they create. Additional nozzles 48 and 49 may also be provided for supplying oxygen gas to desired levels of -38 zone and / or zone 39, which are connected from pipelines 44 (FIG. 2). The nozzles 50 are placed in substantially the same manner as the burners 40. Through them, solid carbonaceous or carbon-containing reducing agent is fed into the shaft, which is post-f from pipes 51 and 52, and it is converted to coke at a temperature prevailing in mine. In this embodiment, the carrier gas for the reducing agent is oxygen gas, which flows to the nozzles 50 through pipelines 53 responding from the pipelines 44. During passage from the burners 40 through zone 38, the concentrates 1 are burned and the return dust is burned with the burned materials. products are melted. the continued passage of these products through the mine zone 39 of the iron oxide and the return dust is partially restored to a certain extent. The molten and partially reduced iron oxide together with the coke formed from the reducing reagent and the burnt limestone are fed to the surface 54 of the layer of material present in the lower part of the shaft 1 and the reactor zone 2. The molten iron oxide reacts in the upper zone of the coke layer with further simultaneous recovery and cooling. Then, 99 the material in the bed becomes semi-fluid or pasty. The EEC material is finally regenerated and melted in the reactor zone 2 with the consumption of a further amount of coke, resulting in the formation of liquid iron, and the molten slag accumulates in the lower part of the reactor zone. During the reduction process, gases containing carbon monoxide, which pass upward through the shaft together with the gases formed during coking, are phase out. These gases are partially oxidized during the reaction with the molten oxide of the material in zone 39 and finally burned with oxygen gas flowing through the nozzles 46, or, if necessary, through the nozzles 48. The molten iron and slag are removed through the device 31. The amount of recovered . The agent loaded into the mine is selected so that a coke layer is maintained on the bath of iron and slag. When passing through a layer of coke in the molten slag, the iron content decreases, silicon forms during recovery, and pig iron carburized Required for melting and final reduction of the hourly reduced iron, energy is supplied to the reactor zone by means of electroinductive heating of the material contained in it. For this, an induction coil is provided around the reactor zone, which is powered by alternating current. A portion of the physical heat of the slag removed can be recovered by using this heat to burn the limestone, which is subsequently used in the process as a slag former. To this end, the pig iron and the slag are passed from the outrigger 31 to the sheathed section of the ushemus fixture 55, from which molten slag and cast iron are extruded through different channels. A portion of the slag is passed to the tank 56, where it interacts with tc containing limestone to the material that is loaded into the tank 56 through the inlet 57. Then limestone is burned and the slag hardens, when carbon dioxide is released, passed through the release 58. Hot mixture the slag and the burned 1eveshka is ground in the device 59 to the required size: particles, after that it is loaded into the shaft, preferably still in the heated state, and either through the storage hopper or directly into the burner 40. The residual slag, not limestone used for roasting is discharged through pipeline 6O. From zone 38 (FIG. 3) a gas can be used which has a relatively high sulfur content, from which sulfur can be recovered to the elementar. form, for example, using pro-. Cessa Klaus. To do this, it is necessary for the gas to contain KO2O, which in the Claus process react with each other to form HjiO and S. For this purpose, a mixture of water vapor and oxygen gas is used as a carrier gas for the material entering through the burners 40. Such a mixture is also loaded through nozzles 46. When there are nozzles 48 in the upper part of zone 38, they can supply more enriched gas steam than that supplied through nozzles 46. The carrier gas used for the reducing agent charged via pipelines 51 and 52 consists essentially entirely of oxygen, which is supplied through pipelines 60, which can be connected wires 61 for feeding nozzles 62. The latter can be located in the same way as nozzles 49 by 2 and serve to at least partially combust combustible gas in the upper part of the shaft zone 39. roared gas is taken from zone 39. through the outlet pipe 63 in order to prevent roasting gas dilution. The residual heat content of the off-gas can be recovered in the steam boiler in the same way as shown in FIG. 1. Due to the simplicity of the device for the implementation of the proposed method and the fact that. the installation does not require coke sintering systems, and in some cases even separate binder systems, capital costs are significantly lower than those associated with a conventional blast furnace process, even for relatively small units per tonne capacity. PRI me R. In the burning zone of the mine load is 2O 44 O kg / h of lead sulfide concentrate, which has 75% by weight of lead. During the same period, 15OO kg of lime, 310 kg of coke are loaded into the furnace. 170 kg of heavy fuel misla and 6000 kg of returnable dust, essentially in the form of lead sulphate. The oxygen demand is 3000 im / h based on 1% OQ. The molten in flame and partially recovered material, from which 30% by weight of lead contained was oxidized to PBO, has a temperature when it reaches an inductive heating reactor connected to the lower part of the gap. Every hour I extrude 15,000 kg of molten lead from a reactor at 800 ° C to 2700 kg of slag at 1250 ° C. From the hourly hour, 410 O of the gas is taken, it has a temperature of laOO C. The gas contains 52% by volume of SO and 44 OO kg of dust in the form of PHO, and this dust is sulphated with sulfur dioxide in the gas and separated in the boiler and the gas-cleaning apparatus, after which it returns to the form of a return (it grows into a returnable dust containing lead sulphate. Hourly in a boiler, high-pressure steam is produced, having an energy content of 2100 kWh. This steam is used to drive a steam turbine with a capacity of 690 kWl of electricity, which 130 kWh go for n production of oxygen gas, and 56 kWh for reactor operation. formula-invention A method for producing a metallic melt from crushed iron ore material, including loading it into a furnace, partially reducing it with gaseous combustion products and subsequent final reduction with carbon, characterized in that with a chain process intensification, partial reduction of opacification, together with melting by tangential supply of iron ore material, solid carbonaceous reducing agent and acid generic; the gas to the flame, and the re-reduction is carried out by the residual solid reducing agent present in the molten material. Sources of information taken into account in the examination 1. US patent number 3607217, CP. 75-4 1974. 2. US Patent No. 193001O, Cl. 75-4, 31.958. 3. USSR Author's Certificate No. 45304, cl. From 21 to 13/02, 1935.

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Claims (1)

Claim A method of producing a metal melt from crushed iron ore material, including loading it into a furnace, partial reduction with gaseous products of combustion and subsequent final reduction with carbon, characterized in that, in order to intensify the process, partial reduction is carried out. together with melting by tangential feeding of iron ore material, solid carbonaceous reducing agent and oxygen-containing! gas to the combustion torch, and additional reduction is carried out by the residual solid reducing agent present in the molten material. ₍