SU520402A1 - Cokeless liquid metal production method - Google Patents

Description

(54)

Method of bespoke production of liquid metal

The invention relates to the field of metallurgy and can be used to produce iron, steel or an intermediate in ferrous metallurgy.

A known method of coke-free production of liquid metal from iron oxides, including the reduction of iron oxides in a dense layer; the subsequent melting of the recovered material in a certain aggregate without cooling before melting; use the thermal and chemical energy of gases formed in the melting unit to heat and reduce materials in a dense layer.

The disadvantage of this method is the difficulty of dispensing with mechanical devices the consumption of the recovered material in a hot state from the reducing unit to the smelting unit.

In addition, the disadvantages of the known method include the limited possibilities of the intensity of the process and the lie of the controlled nature of the periodic (cyclic) receipt of the recovered materials from the recovery zone to the melting zone and, as a result, the inability to control the process. B zones themselves for the recovery and smelting of mine areas. LLK of this method is characterized by degraded gas distribution over the cross section and gas circulation of the layer, reduced icing of the heat and mass transfer processes in the layer and low degree of use of the reducing gas due to the reduction of the cyclic (periodic) process in the suspended and therefore fixed bed. In addition, the frequency of release of a significant amount of recovered materials to the melting zone leads to the last-dimensional work of the latter, deterioration of its operating conditions, and to the melting zone of materials with a temperature reduction that is less than a given, cyclical nature of the temperature change. Tep: ia.i ; a in the layer, to the possibility of overheating of the recovered material near the zone

release, its caking and zavas: iii over the latter. All ethn neaos1-. p.cnvr to roHii KonHio quality of the metal and the technical and economic indicators. process a whole. The aim of the invention is to eliminate these drawbacks by providing independent control over BOSS processes in the moving layer and melting them by adjusting the constant supply of the recovered material from the recovery zone to the melting zone, i.e., eliminating the periodic (cyclic) nature of the recovery processes. in the fixed layer, the melt layer and the materials recovered to a given degree. For this, a method has been proposed whereby the reducing gas at SOO-llOO-C in the amount of 6 ~ 99 o of the total gas consumption is introduced above the production zone of the recovered materials and in the amount of 40-1% below the zone, while maintaining the specified degree of recovery of materials in a dense moving bed, it is carried out by varying the flow rate of the second reducing gas stream within the specified limits while maintaining the total reducing gas flow rate constant. In order to further control the degree of reduction and productivity, the pressure of the gas flow is osstanovitel introduced below the outlet zone proposed varied by superimposing and the amplified Sliding N5tyh phase from O to 18O natural oscillations induced with frequency of -10 Hz during collapse and the formation of unstable dynamical arches over the release area of the reduced materials. The essence of the proposed method lies in the fact that the gas reducing agent below the discharge zone of the recovered materials is supplied in an amount insufficient to add materials in the recovery zone but necessary to maintain a three-fold lowering speed of the layer, and above the discharge zone in an amount that ensures the specified material recovery rate at a constant total consumption of the reducing gas. The method is carried out as follows. On the top of the shaft furnace load ok thousand, agglomerate or lump iron ore. In the reduction zone, the oxides of the glands are reduced to a predetermined degree by a counter-flow of reducing gas in a dense moving layer and through the discharge zone enter the melting zone. The release zone dividing the reduction and melting zones, depending on the size of the shades determined by the capacity of the installation, can be made in the form. .... -, .... one, two or more holes. Southeastern gas gazel was introduced in two streams, respectively, below the outlet zone and above the latter, but at the max 11: / possible within 800-1100 ° С, but not starting the beginning of the hemiegurus. hoarded material. The flow rate of the reducing gas of the first stream introduced above the discharge zone is 60-99%, and below it (the second stream), respectively, 40-1% of the total gas flow. The rate of movement of materials from the reduction zone to the melting zone is controlled by changing within the specified limits the flow rate of the reducing gas introduced below the discharge zone, while maintaining the total gas flow constant. The rate at which the recovered material enters the melting zone does not depend on the flow rate of the first gas stream blown above the outlet zone. At the same time, the speed of the sample of the recovered material from the reduction zone to the melting zone can be measured from the minimum to the maximum value by thinking, in part, of the flow rate of the second gas stream blown below the outlet zone. The rate at which the material enters the PLG zone; Vlenp determines its residence time in the recovery zone, and hence the degree of recovery. In this case, in each particular case, it is possible to ensure such a rate of material entry into the melting zone, at which a given degree of material reduction (metallization) is achieved in the reduction zone. In the melting zone, melting of recovered materials, separation of metal and slag, carburization of metal in the production of pig iron, alloying of metal, etc. occur. Melting of materials and overheating of the melt occurs due to electric arc or induction heating. When operating according to the proposed method, pressure fluctuations of the gas flow occur, which are caused by the natural process of formation and destruction of the dynamo of unstable vaults in the discharge zone with a frequency of the order of 10 -1 Hz. The amplification of these oscillations by means of known devices makes it possible, in particular, to attenuate the processes of recovery and heat transfer in a layer of materials 1, 31, 5 times and thereby increase the rate of flow of material into the melting zone at a constant degree of material reduction or Increase the degree of material recovery at constant performance. To change the rate of entry of the material into the fusion zone at a constant flow rate of the second} pelvic flow, as well as to expand the possibilities of controlling this speed, the period of enhanced pressure fluctuations of the gas flow is shifted in phase from 0 to 18 ° relative to the natural oscillatory process of formation and destruction of the dynamically unstable arches over the issue area. Example. The metal is obtained by reducing the hematite pellets of the Sokolovsko-Sarbaysky ore-dressing plant with a reducing gas consisting of 5O% H2 and 5O; CO, installation speed of 1OO ton / day is the need to increase the flow rate of the gas stream introduced below the outlet zone from 7 to 11.9% to 20.6-35.6% of the total race of reducing gas. The imposition of a gas stream introduced below the outlet zone, pressure oscillations with an intensity of 10,100 W / m and a frequency equal to the collapse frequency of dynamically unstable arches above the outlet zone (0.8-7.2 Hz) reduces the recovery time by 30% and increases uniformity reducing the diameter of 1O mm for which, respectively, increase the rate of pellet ingress into the melting zone by reducing the flow rate of the gas stream introduced into the outlet zone from 12, 12O, 89s. up to 9.3-16.0% of the total consumption of the reducing gas. An increase in productivity from 1OO to ZOO t / day with the recovery of gai pellets with a diameter of 5 mm is possible with a decrease in the gas consumption introduced below the outlet zone, from 7–11.9% to 2% of the total gas consumption. Due to the phase shift from 0 to 18 ° C, the increased pressure fluctuations of the gas flow introduced below the outlet zone, in relation to the natural oscillatory process of formation and destruction of dynamically unstable vaults, make KoppeKTiipooKy the flow rate oKaTbmieii into the melting zone using 9OOC in a dense layer and a constant flow of pellets mobilized by 95% to the melting zone through the total area O, ОО95 m-, to obtain data on the ratio of the reducing gas flow rates, Below the outlet zone, the diameter of the alloys was changed from 5 to 2 mm, the capacity was set from 1OO to ZOO t / day, the total consumption of the gas-reducing agent was from YuOO to 17OO metal. Data at Win) W1 in the table. It follows from the table that an increase in the diameter of the pellets from 5 to 2 O mm when producing a given degree of metallization (95%) and additional regulation in the process without changing the ratio of gas flow rates. Measurement of natural oscillations in the process of formation and destruction of dynamically unstable arches can be made by known piezoelectric, capacitive, optical, and other sensors. The electrical signal from the sensors is amplified in terms of voltage and power, and then converted. into acoustic oscillations with a predetermined phase. The latter are applied to the gas stream, entered below the discharge zone. The total flow rate of the reducing gas is established in the range of 1000 -1700 m / t of metal in order to ensure optimal CKopoCTii reduced pellets and the degree of use of gas depending on the required degree of reduction of the pellets, their recoverability, etc. As seen from the table, with an increase in total at a constant production of the reducing gas flow rate, the fraction of the flow rate of the gas stream introduced below the zone is reduced. The limits of change in the flow rate of the gas stream introduced below the outlet zone are 1–4 ° of the total gas flow rate, selected from the following considerations: upper limit, i.e., 4O% is limited by the possible performance of the installation, and e.

. - provision of the required time for pre-treatment of iron-containing materials in the area of Bosstanstlepi.

Claims (1)

Invention Formula A cokeless metal production method from iron containing materials, including the reduction of oxides with a reducing gas, characterized in that, c. the purpose of raising heat ivietia in the layer and control of the degree of recovery of the depletion of the material E1 11a, (a and its loading into the melting zone, reducing gas in the flow) for 8OO-llOO ° C in the amount of 60-99% of the total consumption is introduced above the unloading zone and in the amount of 1 "4O % under this zone, while the flow of reducing gas under the discharge zone is controlled by changing and increasing the gas below this zone by superposing the filtered gas with a frequency of 1O 1-1о2 Hz that are out of phase to 18 °.