CA2372809A1 - Method and installation with smelting and reduction cyclone and a coupled lower furnace for utilising residual material containing iron and heavy metals and optionally iron ore - Google Patents
Method and installation with smelting and reduction cyclone and a coupled lower furnace for utilising residual material containing iron and heavy metals and optionally iron ore Download PDFInfo
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- CA2372809A1 CA2372809A1 CA 2372809 CA2372809A CA2372809A1 CA 2372809 A1 CA2372809 A1 CA 2372809A1 CA 2372809 CA2372809 CA 2372809 CA 2372809 A CA2372809 A CA 2372809A CA 2372809 A1 CA2372809 A1 CA 2372809A1
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/02—Working-up flue dust
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/14—Multi-stage processes processes carried out in different vessels or furnaces
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/56—Manufacture of steel by other methods
- C21C5/567—Manufacture of steel by other methods operating in a continuous way
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B5/00—General methods of reducing to metals
- C22B5/02—Dry methods smelting of sulfides or formation of mattes
- C22B5/12—Dry methods smelting of sulfides or formation of mattes by gases
- C22B5/14—Dry methods smelting of sulfides or formation of mattes by gases fluidised material
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Materials Engineering (AREA)
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- Geology (AREA)
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Abstract
The invention relates to a method and installation for utilising residual material which contains iron, heavy metals and optionally iron ore. In said method, the following take place: residual material and optionally the iron ore is introduced into a smelting cyclone (1) with a backflow and a base opening which has a narrowed section. Reducing agents and oxygen are additionally introduced into the smelting cyclone (1) and are subjected to swirling. Iron is reduced at least to FeO in the smelting cyclone (1), heavy metals are reduced to metals in the smelting cyclone (1) and are converted into the gas phase by evaporation. The resulting gas which optionally contai ns heavy metals, the partially reduced iron and the slag are transferred to a furnace (5) which is directly adjacent. Energy, in electrical form is then supplied to said furnace (5), preferably using a direct electric arc. Reduci ng agents and oxygen, or oxygen-enriched air is then introduced into the furnac e (5) and the iron is completely reduced and melted in the furnace (5). The evaporated heavy metals are condensed outside the furnace (5), whereby the iron can be subjected to further processing and a deposition of the residual materials is avoided.
Description
Method and Installation with Smelting and Reduction Cyclone and a Coupled Lower Furnace For Utilising Residual Material Containing Iron and Heavy Metals and Optionally Iron Ore The invention aerates to a process and a plant for utilizing iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore.
A major problem of the iron- and steelmaking industry is the continuous production of quantities of iron-containing and heavy-metal-containing remainder materials, such as for example furnace dusts, sludges, rolling scale and the like, which are only available for reuse with considerable outlay and therefore are generally landfilled without the benefit being extracted from their materials of value.
For ecological and economic reasons, there is a need to separate the iron which is present in the remainder materials from its accompanying metals and to return it to the iron- or steelmaking process.
One process of the type described in the introduction is the INMETCO process. In this process, iron-rich metallurgical remainder materials are agglomerated with solid reducing agents to form unburned, so-called "green" pellets and are reduced in a rotary hearth furnace, so that the heavy metals are vaporized, are extracted with the off-gas and are then melted down or optionally hot-briquetted in a melting furnace.
The drawbacks of this process are the need for a pretreatment stage, in which the remainder materials are agglomerated, and in the separately carried out reduction and melting process, with the result that the energy to heat up the remainder materials has to be applied twice and a dedicated off-gas system is required for each stage.
A major problem of the iron- and steelmaking industry is the continuous production of quantities of iron-containing and heavy-metal-containing remainder materials, such as for example furnace dusts, sludges, rolling scale and the like, which are only available for reuse with considerable outlay and therefore are generally landfilled without the benefit being extracted from their materials of value.
For ecological and economic reasons, there is a need to separate the iron which is present in the remainder materials from its accompanying metals and to return it to the iron- or steelmaking process.
One process of the type described in the introduction is the INMETCO process. In this process, iron-rich metallurgical remainder materials are agglomerated with solid reducing agents to form unburned, so-called "green" pellets and are reduced in a rotary hearth furnace, so that the heavy metals are vaporized, are extracted with the off-gas and are then melted down or optionally hot-briquetted in a melting furnace.
The drawbacks of this process are the need for a pretreatment stage, in which the remainder materials are agglomerated, and in the separately carried out reduction and melting process, with the result that the energy to heat up the remainder materials has to be applied twice and a dedicated off-gas system is required for each stage.
In a process which is described in DE-A-44 39 939, remainder materials are melted down in a melting cyclone, the heavy metals are vaporized and are separated out of the off-gas as a dust fraction after oxidation has taken place. The levels of heavy metals in the slag which remains are further depleted in a lower furnace by blowing on reducing gas and oxygen and the slag is then used as a starting material for the production of cement or rockwool. However, in this process the iron is not reused, and consequently a significant constituent of the remainder materials remains unused.
One problem in the production of pig iron is the fine-ore content, of which there are relatively high levels and which is difficult to handle during the reduction and smelting process. Consequently, the reduction of the fine ore usually takes place in fluidized bed reactors, which entail high levels of technical outlay.
Introducing the reduced fine ore into a melting furnace also requires complex apparatus, the service life of which is greatly restricted on account of the wear caused by the reactivity of the iron sponge.
It is known from US-A-5,639,293 to carry out preliminary reduction of iron ore by making the iron-ore particles turbulent using oxygen and a reducing gas in a melting cyclone and collecting the melted iron particles in a metallurgical vessel beneath the melting cyclone and then fully reducing them by blowing in oxygen by means of a lance which projects centrally through the melting cyclone and adding fuel, leading to the formation of a reduction gas which rises into the melting cyclone and, after it has reacted with the iron ore, is extracted at the upper end of the melting cyclone together with off-gases which form.
The cooling action of the oxygen lance which projects centrally through the melting cyclone into the melting vessel in accordance with US-A-5,639,293 may lead to skull formation of the prereduced iron ore.
A device for reducing and melting down iron ore is described in EP-A-0735146. According to EP-A-0 735 146, iron ore is reduced and melted in a melting cyclone and passes into a metallurgical vessel which directly follows beneath the melting cyclone and in which, while a process gas forms from coal which is blown onto the slag/metal layer and oxygen which is blown in, the final reduction and the complete melting of the iron take place. The reducing process gas is partially burnt with oxygen and, in this way, supplies the heat required for the melting and reduction both in the melting vessel and in the melting cyclone. The off-gases are extracted at the upper opening of the melting cyclone.
To separate slag and pig iron, the molten material first has to be transferred into a settling vessel, since in these known devices there is in each case only one tapping hole in the lower vessel.
On account of the open melting cyclone base and the associated lack of return flow in the melting cyclone, the countercurrent guidance and the associated turbulence of the reduction gas with respect to the iron-ore particles leads to an increased level of dusting, and this is made even worse by entrained slag particles and leads to considerable discharges of particles from the melting cyclone with the off-gas which is discharged from the melting cyclone at the top.
The invention aims to eliminate these drawbacks and sets the object of providing a process and a plant which make it possible to process iron-containing and heavy-metal-containing remainder materials, in particular from the iron- and steelmaking industry, and, if appropriate, iron ore in an environmentally friendly manner - avoiding landfill - so that the iron can be utilized, i.e. can be used beneficially for steelmaking. Furthermore, only a single off-gas flow is generated, thus saving plant costs and minimizing emissions, as well as increasing the possible efficiency of energy recovery.
According to the invention, this object is achieved by the combination of the following features:
- the remainder materials and, if appropriate, the iron ore are introduced into a melting cyclone with return flow, - reducing agents and oxygen are additionally introduced into the melting cyclone and are made turbulent, - in the melting cyclone, iron is reduced at least to FeO, - in the melting cyclone, heavy metals are reduced to form metals and are converted into the gas phase by vaporization, - the resulting gas, which may contain heavy metals, the partially reduced iron and the slag are transferred into a directly coupled furnace, - energy is supplied to the furnace, - reducing agents and oxygen or oxygen-enriched air are introduced into the furnace, - iron is fully reduced and partially melted in the furnace, and - the vaporized heavy metals are precipitated outside the furnace.
The meaning of the terms 'iron", 'iron-containing", "heavy-metal" and "heavy-metal-containing" in each case encompass both the corresponding metals in oxidized, for example oxidic, form, and in reduced, i.e.
metallic, form, and specifically both in oxidized and reduced form and in only one of the two forms; the precise meaning becomes clear from the context.
_ 5 _ In this context, the term "reduction to Fe0" is always to be understood as meaning reduction from trivalent to divalent iron, i.e. from FeZ03 to 2Fe0, but also from 3Fe~03 to 2Fe304 ( i . a . to Fe203~Fe0) .
Furthermore, the use of a melting cyclone with return flow, which is effected by a constriction in the base of the melting cyclone, allows a low level of dusting to be achieved. The iron-containing and heavy-metal-containing remainder materials and, if appropriate, the iron ore, on account of the return flow, achieve a longer residence time in the melting cyclone and are transferred into the furnace only in the liquid or gaseous state. Even when the melting cyclone is arranged above the furnace, slag particles are prevented from entering the melting cyclone by the constriction. Moreover, there is only one outlet opening, which is provided in the bottom of the melting cyclone, so that particles cannot be discharged by means of a gas flowing upward through the melting cyclone. According to the invention, all the materials and gases which have been introduced into the melting cyclone are forced to move into the furnace, where they can be fully processed efficiently. This also has the advantage of a single off-gas flow, namely from the furnace, which accordingly can be treated easily and inexpensively.
It is advantageously also possible to use fine ore as iron-containing remainder material, in particular with a proportion of extremely fine particles which originate from the ore beneficiation or from the fines from a pelletizing device.
The introduction of reducing agents, which are advantageously introduced in solid, liquid or gaseous form, and oxygen, preferably industrial-grade oxygen or oxygen-enriched air, takes place horizontally, preferably tangentially, into the vertically arranged melting cyclone, with the result that the mass transfer and heat exchange operations proceed very quickly.
Reducing agents and oxygen are added in controlled quantities which are such that the heavy metals, during the melting operation, are converted into the gas phase by being vaporized in the metallic state, and the iron is reduced at least to divalent iron oxide FeO.
The heavy-metal-containing gas, the partially reduced iron and the slag are transferred into the furnace from the melting cyclone by means of a connecting line which is arranged between the bottom opening of the melting cyclone and a furnace which directly follows the melting cyclone, preferably through the top or through a side wall of the furnace, and, if appropriate, via at most one intermediate chamber which is arranged on the wall of the furnace and allows particularly effective separation of the melting zone from the reduction zone in the furnace. The intermediate chamber into which the connecting line opens may also be designed as a furnace off-gas line.
To reduce the partially reduced iron which is present in the form of divalent iron oxide in the molten material to form metallic iron, solid reducing agent, preferably coal or carbon-containing waste materials (which are at least partially formed by fine particles), is blown into the molten material with oxygen or oxygen-enriched air. The step of blowing in these substances may take place via below-bath blowing nozzles or via lances which penetrate into the slag layer floating on the molten metallic iron. For this purpose the furnace is provided with openings for the lances. The blowing nozzles are expediently partly below the level of the metal bath and are connected to feeds for reducing agents and/or oxygen. The lances may - 7 _ be arranged in the furnace in any manner which is known to the person skilled in the art.
On account of the difference in density, the reduced metal droplets settle at the bottom of the furnace in the molten metallic iron, and like the slag can advantageously be tapped separately from the furnace, continuously or discontinuously, via a dedicated tapping hole.
In addition to the iron-containing and heavy-metal-containing remainder material(s), which has/have been melted down and prereduced in the melting cyclone, and, if appropriate, iron ore, some coarse fraction may be charged directly to the furnace, preferably via a dedicated feed which opens into the furnace, for example in the top or a side wall of the furnace.
To maintain the temperature which is required in order to tap off slag and molten pig iron, energy is supplied to the furnace, and this also prevents premature separation of the heavy metals in the region of the furnace. The energy is preferably supplied in the form of electrical energy, for example via a direct arc, to the molten material. It has proven particularly advantageous for the electrical energy to be supplied by means of at least one electrode projecting into the furnace; both direct current and alternating current are possible.
The evaporated heavy metals, together with the furnace off-gas, are afterburned directly at the gas outlet, with the result that the heavy metals are converted into a solid oxidic form which, after separation from the remaining off-gas in a precipitation device, can be fed for further processing.
If the products originating from the melting cyclone, namely heavy-metal-containing gas and molten material, are firstly introduced into an intermediate chamber, the heavy-metal-containing gas is introduced into the furnace off-gas, which is extracted from the furnace via the intermediate chamber, in this intermediate chamber, whereupon the further treatment of the gases takes place jointly.
The melting cyclone, the furnace vessel above the metal level and, if appropriate, the intermediate chamber are expediently equipped with evaporation cooling, with the result that the radiant heat from the furnace and the melting cyclone can be used to evaporate cooling water and can therefore be recovered in the form of steam, which can be used to save energy within a metallurgical plant.
The same purpose is served by off-gas cooling, preferably in a steam boiler, carried out following the afterburning of the heavy-metal-containing gas and the.
furnace off-gas.
The utilization of the heat which is inherent to the off-gas may advantageously also take place completely or partially in a heat exchanger into which the off-gas line of the furnace opens, it being possible to feed the heated air to a dryer which dries iron-containing and heavy-metal-containing, wet remainder materials or slurries which are suitable for use in the melting cyclone.
The invention is explained in more detail below with reference to exemplary embodiments which are illustrated in the drawing, in which Fig. 1 to 4 show diagrammatic views of preferred embodiments of the plant according to the invention.
In accordance with Fig. 1, coal, oxygen and iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore in the form of dust are introduced into a vertically arranged melting _ g _ cyclone 1. The introduction takes place in such a manner that the turbulence and the associated mass and heat transfer processes in accordance with the invention take place very quickly, with the result that the melting and prereduction process overall has a high space-time yield. The controlled release of the substances which are to be introduced into the melting cyclone 1 is effected by a metering device, which is not shown but is known to the person skilled in the art . The substances are blown into the melting cyclone 1 horizontally, preferably tangentially, via a plurality of openings, which may be distributed over the entire jacket of the melting cyclone.
Reduction of the iron-containing and heavy-metal-containing remainder materials and, if appropriate, of the iron ore takes place in the interior 2 of the melting cyclone 1, iron being reduced at least to Fe0 and the heavy metals being reduced to the metal.
Furthermore, melting of the reduced iron-containing material and conversion of the heavy metals into the gas phase is achieved quickly and efficiently on account of a cyclone-specific return flow.
An opening 3 in the bottom 4 of the melting cyclone 1 is formed by a constriction which causes the return flow in the interior 2 of the melting cyclone 1 and therefore allows minimal dusting to be achieved.
The melting cyclone 1 is directly connected to a furnace 5 which is arranged beneath the melting cyclone 1. The melted products and the heavy-metal-containing gas pass into the furnace 5 from above via a connecting line 6.
In the furnace 5 there are a metal bath 7 (iron bath) and a slag layer 8 which floats on the metal bath 7, and these constituents are removed separately from the furnace 5 via tapping holes 9 and 10. Furthermore, according to this embodiment, the furnace 5 has three electrodes 11, 11', 11" which are immersed in the slag layer 8 from above and supply the energy which is required to maintain a liquid slag 8 and a metal bath 7 S in the form of arcs. In this example, the electrodes 11, 11', 11" are operated with alternating current, although operation with direct current would also be possible, in which case the furnace 5 would have only one electrode 11.
Reducing agent and/or oxygen is introduced into the furnace 5 via below-bath blowing nozzles 12 in a side wall 13 of the furnace 5 or in the bottom 14. Some of the blowing nozzles 12 are preferably arranged below the metal bath level.
In addition, in the embodiment shown in Fig. 1 there is a lance 15 for blowing in coal and oxygen, which projects obliquely into the furnace S through the side wall 13 of the furnace 5 and the lower end of which is immersed in the slag layer 8.
Moreover, a feed 16 for a coarse fraction of a reducing agent or a remainder material which can be introduced if appropriate opens into the furnace 5.
The iron-containing molten material which is introduced into the furnace 5 from the melting cyclone 1 is fully reduced in the slag layer 8 with the aid of the reducing agent and the oxygen, and the liquid iron is separated out into the metal bath 7.
On emerging from the furnace 5, air is fed to the off-gas and afterburning 21 is initiated. Some of the energy content of the off-gas, which has been increased in this way, is transferred to water in a heat recovery steam generator 17, the heat content of the off-gas being used to generate steam. An example for the further use of the steam is a turbine generator 18 which is used for current generation. However, other possible uses for the steam which is generated are also conceivable, for example use in the metallurgical plant for cooling purposes, etc.
Following the boiler 17, the cooled off-gas is fed to a filter 19, in which the condensed heavy metals, which are in the form of dust, are separated from the remaining off-gas.
The preferred embodiment illustrated in Fig. 2 differs from the embodiment illustrated in Fig. 1 with regard to the way in which the heavy-metal-containing gas and the melted material from the melting cyclone 1 are introduced into the furnace 5. In this embodiment, the connecting line 6 opens out in the side wall 13 of the furnace 5. The reducing agent and the oxygen are introduced into the furnace 5 only via below-bath blowing nozzles 12. The further treatment of the off-gas after it leaves the furnace 5 is not shown in further detail; it may take place in the same way as that shown in Fig. 1.
In accordance with Fig. 3, the connecting line 6 opens out in an intermediate chamber 20, which is designed as an optionally widened (as illustrated by dashed lines) off-gas line, so that the heavy-metal-containing gas from the melting cyclone 1 does not need to flow through the furnace 5, and the melted material is already reduced further on the way into the furnace 5 by the reducing furnace off-gas . In this embodiment of the plant according to the invention, the lance 15 which is used to blow in reducing agent and oxygen projects into the furnace S from above. However, it may also project through a side wall 13 into the furnace 5.
Fig. 4 shows the arrangement of melting cyclone 1 and furnace 5 which is described in Fig. 1, but in this case the heat which is inherent to the off-gas is only partially utilized in the heat recovery steam generator 17. The off-gas which is still hot undergoes heat exchange in a recuperator 22 and is then, in the cooled state, passed into the filter 19, where the above-described separation of the heavy metals takes place.
The air which is heated in the recuperator 22 is fed to a dryer 23 which is used to dry wet remainder materials and slurries for use in the melting cyclone 1.
The process sequence according to the invention is explained with reference to the following Examples 1, 2 and 3. The quantity data are in each case based on one tonne of charge mixture without coal or additives (lime) .
Example 1:
1000 kg/h of iron-containing and heavy-metal-containing remainder materials, which had a composition as shown in Table 1, and 105 kg/t of coal were introduced into the melting cyclone with 112 m3/t (s.t.p.) of deliver air, and were made turbulent using 250 m3/t (s.t.p.) of oxygen. 5.4 m3/t (s.t.p.) of fuel gas (natural gas) were supplied in order to ignite the solid/gas mixture in the melting cyclone and to maintain a pilot flame.
Table 1 Example 1 Example Example Charge Unit Remainder- Remainder-Iron ore mixture material mix material without iron mix 2 with ore iron ore Chemical analysis -A1Z03 % by weight 0.67 0.90 0.63 -C % by weight 7.9 15.2 --Ca0 % by weight 5.5 5.1 3.0 -Fe % by weight 10.0 0.70 --Fe0 % by weight 34.4 20.1 --Fe203 % by weight 31.7 46.7 90.6 -Mg0 % by weight 1.69 1.1 0.36 -Mn0 % by weight - 0.10 0.17 -K + Na % by weight 0.15 0.24 0.04 -C1 + F % by weight 0.80 0.13 --Pb + Zn % by weight 0.30 1.7 0.01 -Si02 % by weight 3.13 3.6 4.0 -S % by weight 0.15 0.10 0.05 -P % by weight 0.15 0.10 0.05 The partially reduced iron was then fully reduced and partially melted in the reduction furnace with 182 kg/t of coal and 36 m3/t (s.t.p.) of oxygen. The amount of delivery air for the solids blown in through lances or nozzles was 45 m3/t (s.t.p.). The current consumption of the furnace was 320 kwh/t.
576 kg/t of molten metal, 130 kg/t of slag and a dedusted off-gas quantity of 12,140 m3/t (s.t.p.) were obtained. 24 kg/t of heavy-metal-containing dust was separated out of the off-gas. Furthermore, 737 kWh/t of current were generated by utilizing the waste heat in a steam generator.
The composition of the molten metal, of the slag, of the off-gas and of the separated dust is given in Table 2. Examples 2 and 3 resulted in product compositions which lay within the same range.
Table 2 Molten metal -C % by weight 2.0 - 3.0 -Mn % by weight < 0.2 -Si % by weight 0.1 - 0.2 -S % by weight < 0.09 -P % by weight < 0.08 Slag -Fe0 % by weight 3.0 - 6.0 -Ca0 % by weight 38 - 44 -Si02 % by weight 30 - 36 -Mg0 % by weight 7.0 - 12 -A1203 % by weight 5.0 - 10 Off-gas -C02 % by volume 6.5 - 7.5 -02 % by volume 16 - 17 -Hz0 % by volume 1.0 - 1.5 -Nz + Ar % by volume Remainder Dust -Fe0 % by weight 30 - 75 -Zn0 % by weight 5 - 50 -Pb0 % by weight < 5.0 -Si02 % by weight < 5.0 -Ca0 % by weight < 7.0 Example 2:
A quantity of 1000 kg/h of iron-containing and heavy-metal-containing remainder materials and iron ore - the composition of the charge mixture is given in Table 1 -with 56 kg/t of coal was introduced into the melting cyclone by means of 106 m3/t (s.t.p.) of delivery air and was made turbulent using 270 m3/t (s.t.p.) of oxygen. 5.1 m3/t (s.t.p.) of fuel gas were supplied.
The amount of reducing agent (coal) introduced into the furnace was 151 kg/t, the amount of oxygen was 30 m3/t (s.t.p.) and the amount of delivery air was 38 m3/t (s.t.p.). The current consumption was 268 kWh/t.
480 kg/t of molten metal, 125 kg/t of slag, 11,900 m3/t (s.t.p.) of dedusted off-gas and 36 kg/t of heavy-metal-containing dust were obtained. The current production was 684 kWh/t.
Example 3:
The charge product used was 1000 kg/h of iron ore (composition: Table 1) with 290 kg/t of coal and 136 m3/t (s.t.p.) of delivery air. Furthermore, 336 m3/t (s.t.p.) of oxygen and 55 kg/t of lime were introduced into the melting cyclone. The amount of fuel gas was 6.5 m3/t (s.t.p. ) .
To reduce the iron, 197 kg/t of coal were fed to the furnace with 49 m3/t (s.t.p.) of delivery air and 38 m3/t (s.t.p.) of oxygen. The current consumption was 348 kWh/t.
The products obtained were 625 kg/t of molten metal, 139 kg/t of slag, 15,760 m3/t (s.t.p.) of dedusted off-gas and 22 kg/t of dust. 945 kWh/t of current were generated.
One problem in the production of pig iron is the fine-ore content, of which there are relatively high levels and which is difficult to handle during the reduction and smelting process. Consequently, the reduction of the fine ore usually takes place in fluidized bed reactors, which entail high levels of technical outlay.
Introducing the reduced fine ore into a melting furnace also requires complex apparatus, the service life of which is greatly restricted on account of the wear caused by the reactivity of the iron sponge.
It is known from US-A-5,639,293 to carry out preliminary reduction of iron ore by making the iron-ore particles turbulent using oxygen and a reducing gas in a melting cyclone and collecting the melted iron particles in a metallurgical vessel beneath the melting cyclone and then fully reducing them by blowing in oxygen by means of a lance which projects centrally through the melting cyclone and adding fuel, leading to the formation of a reduction gas which rises into the melting cyclone and, after it has reacted with the iron ore, is extracted at the upper end of the melting cyclone together with off-gases which form.
The cooling action of the oxygen lance which projects centrally through the melting cyclone into the melting vessel in accordance with US-A-5,639,293 may lead to skull formation of the prereduced iron ore.
A device for reducing and melting down iron ore is described in EP-A-0735146. According to EP-A-0 735 146, iron ore is reduced and melted in a melting cyclone and passes into a metallurgical vessel which directly follows beneath the melting cyclone and in which, while a process gas forms from coal which is blown onto the slag/metal layer and oxygen which is blown in, the final reduction and the complete melting of the iron take place. The reducing process gas is partially burnt with oxygen and, in this way, supplies the heat required for the melting and reduction both in the melting vessel and in the melting cyclone. The off-gases are extracted at the upper opening of the melting cyclone.
To separate slag and pig iron, the molten material first has to be transferred into a settling vessel, since in these known devices there is in each case only one tapping hole in the lower vessel.
On account of the open melting cyclone base and the associated lack of return flow in the melting cyclone, the countercurrent guidance and the associated turbulence of the reduction gas with respect to the iron-ore particles leads to an increased level of dusting, and this is made even worse by entrained slag particles and leads to considerable discharges of particles from the melting cyclone with the off-gas which is discharged from the melting cyclone at the top.
The invention aims to eliminate these drawbacks and sets the object of providing a process and a plant which make it possible to process iron-containing and heavy-metal-containing remainder materials, in particular from the iron- and steelmaking industry, and, if appropriate, iron ore in an environmentally friendly manner - avoiding landfill - so that the iron can be utilized, i.e. can be used beneficially for steelmaking. Furthermore, only a single off-gas flow is generated, thus saving plant costs and minimizing emissions, as well as increasing the possible efficiency of energy recovery.
According to the invention, this object is achieved by the combination of the following features:
- the remainder materials and, if appropriate, the iron ore are introduced into a melting cyclone with return flow, - reducing agents and oxygen are additionally introduced into the melting cyclone and are made turbulent, - in the melting cyclone, iron is reduced at least to FeO, - in the melting cyclone, heavy metals are reduced to form metals and are converted into the gas phase by vaporization, - the resulting gas, which may contain heavy metals, the partially reduced iron and the slag are transferred into a directly coupled furnace, - energy is supplied to the furnace, - reducing agents and oxygen or oxygen-enriched air are introduced into the furnace, - iron is fully reduced and partially melted in the furnace, and - the vaporized heavy metals are precipitated outside the furnace.
The meaning of the terms 'iron", 'iron-containing", "heavy-metal" and "heavy-metal-containing" in each case encompass both the corresponding metals in oxidized, for example oxidic, form, and in reduced, i.e.
metallic, form, and specifically both in oxidized and reduced form and in only one of the two forms; the precise meaning becomes clear from the context.
_ 5 _ In this context, the term "reduction to Fe0" is always to be understood as meaning reduction from trivalent to divalent iron, i.e. from FeZ03 to 2Fe0, but also from 3Fe~03 to 2Fe304 ( i . a . to Fe203~Fe0) .
Furthermore, the use of a melting cyclone with return flow, which is effected by a constriction in the base of the melting cyclone, allows a low level of dusting to be achieved. The iron-containing and heavy-metal-containing remainder materials and, if appropriate, the iron ore, on account of the return flow, achieve a longer residence time in the melting cyclone and are transferred into the furnace only in the liquid or gaseous state. Even when the melting cyclone is arranged above the furnace, slag particles are prevented from entering the melting cyclone by the constriction. Moreover, there is only one outlet opening, which is provided in the bottom of the melting cyclone, so that particles cannot be discharged by means of a gas flowing upward through the melting cyclone. According to the invention, all the materials and gases which have been introduced into the melting cyclone are forced to move into the furnace, where they can be fully processed efficiently. This also has the advantage of a single off-gas flow, namely from the furnace, which accordingly can be treated easily and inexpensively.
It is advantageously also possible to use fine ore as iron-containing remainder material, in particular with a proportion of extremely fine particles which originate from the ore beneficiation or from the fines from a pelletizing device.
The introduction of reducing agents, which are advantageously introduced in solid, liquid or gaseous form, and oxygen, preferably industrial-grade oxygen or oxygen-enriched air, takes place horizontally, preferably tangentially, into the vertically arranged melting cyclone, with the result that the mass transfer and heat exchange operations proceed very quickly.
Reducing agents and oxygen are added in controlled quantities which are such that the heavy metals, during the melting operation, are converted into the gas phase by being vaporized in the metallic state, and the iron is reduced at least to divalent iron oxide FeO.
The heavy-metal-containing gas, the partially reduced iron and the slag are transferred into the furnace from the melting cyclone by means of a connecting line which is arranged between the bottom opening of the melting cyclone and a furnace which directly follows the melting cyclone, preferably through the top or through a side wall of the furnace, and, if appropriate, via at most one intermediate chamber which is arranged on the wall of the furnace and allows particularly effective separation of the melting zone from the reduction zone in the furnace. The intermediate chamber into which the connecting line opens may also be designed as a furnace off-gas line.
To reduce the partially reduced iron which is present in the form of divalent iron oxide in the molten material to form metallic iron, solid reducing agent, preferably coal or carbon-containing waste materials (which are at least partially formed by fine particles), is blown into the molten material with oxygen or oxygen-enriched air. The step of blowing in these substances may take place via below-bath blowing nozzles or via lances which penetrate into the slag layer floating on the molten metallic iron. For this purpose the furnace is provided with openings for the lances. The blowing nozzles are expediently partly below the level of the metal bath and are connected to feeds for reducing agents and/or oxygen. The lances may - 7 _ be arranged in the furnace in any manner which is known to the person skilled in the art.
On account of the difference in density, the reduced metal droplets settle at the bottom of the furnace in the molten metallic iron, and like the slag can advantageously be tapped separately from the furnace, continuously or discontinuously, via a dedicated tapping hole.
In addition to the iron-containing and heavy-metal-containing remainder material(s), which has/have been melted down and prereduced in the melting cyclone, and, if appropriate, iron ore, some coarse fraction may be charged directly to the furnace, preferably via a dedicated feed which opens into the furnace, for example in the top or a side wall of the furnace.
To maintain the temperature which is required in order to tap off slag and molten pig iron, energy is supplied to the furnace, and this also prevents premature separation of the heavy metals in the region of the furnace. The energy is preferably supplied in the form of electrical energy, for example via a direct arc, to the molten material. It has proven particularly advantageous for the electrical energy to be supplied by means of at least one electrode projecting into the furnace; both direct current and alternating current are possible.
The evaporated heavy metals, together with the furnace off-gas, are afterburned directly at the gas outlet, with the result that the heavy metals are converted into a solid oxidic form which, after separation from the remaining off-gas in a precipitation device, can be fed for further processing.
If the products originating from the melting cyclone, namely heavy-metal-containing gas and molten material, are firstly introduced into an intermediate chamber, the heavy-metal-containing gas is introduced into the furnace off-gas, which is extracted from the furnace via the intermediate chamber, in this intermediate chamber, whereupon the further treatment of the gases takes place jointly.
The melting cyclone, the furnace vessel above the metal level and, if appropriate, the intermediate chamber are expediently equipped with evaporation cooling, with the result that the radiant heat from the furnace and the melting cyclone can be used to evaporate cooling water and can therefore be recovered in the form of steam, which can be used to save energy within a metallurgical plant.
The same purpose is served by off-gas cooling, preferably in a steam boiler, carried out following the afterburning of the heavy-metal-containing gas and the.
furnace off-gas.
The utilization of the heat which is inherent to the off-gas may advantageously also take place completely or partially in a heat exchanger into which the off-gas line of the furnace opens, it being possible to feed the heated air to a dryer which dries iron-containing and heavy-metal-containing, wet remainder materials or slurries which are suitable for use in the melting cyclone.
The invention is explained in more detail below with reference to exemplary embodiments which are illustrated in the drawing, in which Fig. 1 to 4 show diagrammatic views of preferred embodiments of the plant according to the invention.
In accordance with Fig. 1, coal, oxygen and iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore in the form of dust are introduced into a vertically arranged melting _ g _ cyclone 1. The introduction takes place in such a manner that the turbulence and the associated mass and heat transfer processes in accordance with the invention take place very quickly, with the result that the melting and prereduction process overall has a high space-time yield. The controlled release of the substances which are to be introduced into the melting cyclone 1 is effected by a metering device, which is not shown but is known to the person skilled in the art . The substances are blown into the melting cyclone 1 horizontally, preferably tangentially, via a plurality of openings, which may be distributed over the entire jacket of the melting cyclone.
Reduction of the iron-containing and heavy-metal-containing remainder materials and, if appropriate, of the iron ore takes place in the interior 2 of the melting cyclone 1, iron being reduced at least to Fe0 and the heavy metals being reduced to the metal.
Furthermore, melting of the reduced iron-containing material and conversion of the heavy metals into the gas phase is achieved quickly and efficiently on account of a cyclone-specific return flow.
An opening 3 in the bottom 4 of the melting cyclone 1 is formed by a constriction which causes the return flow in the interior 2 of the melting cyclone 1 and therefore allows minimal dusting to be achieved.
The melting cyclone 1 is directly connected to a furnace 5 which is arranged beneath the melting cyclone 1. The melted products and the heavy-metal-containing gas pass into the furnace 5 from above via a connecting line 6.
In the furnace 5 there are a metal bath 7 (iron bath) and a slag layer 8 which floats on the metal bath 7, and these constituents are removed separately from the furnace 5 via tapping holes 9 and 10. Furthermore, according to this embodiment, the furnace 5 has three electrodes 11, 11', 11" which are immersed in the slag layer 8 from above and supply the energy which is required to maintain a liquid slag 8 and a metal bath 7 S in the form of arcs. In this example, the electrodes 11, 11', 11" are operated with alternating current, although operation with direct current would also be possible, in which case the furnace 5 would have only one electrode 11.
Reducing agent and/or oxygen is introduced into the furnace 5 via below-bath blowing nozzles 12 in a side wall 13 of the furnace 5 or in the bottom 14. Some of the blowing nozzles 12 are preferably arranged below the metal bath level.
In addition, in the embodiment shown in Fig. 1 there is a lance 15 for blowing in coal and oxygen, which projects obliquely into the furnace S through the side wall 13 of the furnace 5 and the lower end of which is immersed in the slag layer 8.
Moreover, a feed 16 for a coarse fraction of a reducing agent or a remainder material which can be introduced if appropriate opens into the furnace 5.
The iron-containing molten material which is introduced into the furnace 5 from the melting cyclone 1 is fully reduced in the slag layer 8 with the aid of the reducing agent and the oxygen, and the liquid iron is separated out into the metal bath 7.
On emerging from the furnace 5, air is fed to the off-gas and afterburning 21 is initiated. Some of the energy content of the off-gas, which has been increased in this way, is transferred to water in a heat recovery steam generator 17, the heat content of the off-gas being used to generate steam. An example for the further use of the steam is a turbine generator 18 which is used for current generation. However, other possible uses for the steam which is generated are also conceivable, for example use in the metallurgical plant for cooling purposes, etc.
Following the boiler 17, the cooled off-gas is fed to a filter 19, in which the condensed heavy metals, which are in the form of dust, are separated from the remaining off-gas.
The preferred embodiment illustrated in Fig. 2 differs from the embodiment illustrated in Fig. 1 with regard to the way in which the heavy-metal-containing gas and the melted material from the melting cyclone 1 are introduced into the furnace 5. In this embodiment, the connecting line 6 opens out in the side wall 13 of the furnace 5. The reducing agent and the oxygen are introduced into the furnace 5 only via below-bath blowing nozzles 12. The further treatment of the off-gas after it leaves the furnace 5 is not shown in further detail; it may take place in the same way as that shown in Fig. 1.
In accordance with Fig. 3, the connecting line 6 opens out in an intermediate chamber 20, which is designed as an optionally widened (as illustrated by dashed lines) off-gas line, so that the heavy-metal-containing gas from the melting cyclone 1 does not need to flow through the furnace 5, and the melted material is already reduced further on the way into the furnace 5 by the reducing furnace off-gas . In this embodiment of the plant according to the invention, the lance 15 which is used to blow in reducing agent and oxygen projects into the furnace S from above. However, it may also project through a side wall 13 into the furnace 5.
Fig. 4 shows the arrangement of melting cyclone 1 and furnace 5 which is described in Fig. 1, but in this case the heat which is inherent to the off-gas is only partially utilized in the heat recovery steam generator 17. The off-gas which is still hot undergoes heat exchange in a recuperator 22 and is then, in the cooled state, passed into the filter 19, where the above-described separation of the heavy metals takes place.
The air which is heated in the recuperator 22 is fed to a dryer 23 which is used to dry wet remainder materials and slurries for use in the melting cyclone 1.
The process sequence according to the invention is explained with reference to the following Examples 1, 2 and 3. The quantity data are in each case based on one tonne of charge mixture without coal or additives (lime) .
Example 1:
1000 kg/h of iron-containing and heavy-metal-containing remainder materials, which had a composition as shown in Table 1, and 105 kg/t of coal were introduced into the melting cyclone with 112 m3/t (s.t.p.) of deliver air, and were made turbulent using 250 m3/t (s.t.p.) of oxygen. 5.4 m3/t (s.t.p.) of fuel gas (natural gas) were supplied in order to ignite the solid/gas mixture in the melting cyclone and to maintain a pilot flame.
Table 1 Example 1 Example Example Charge Unit Remainder- Remainder-Iron ore mixture material mix material without iron mix 2 with ore iron ore Chemical analysis -A1Z03 % by weight 0.67 0.90 0.63 -C % by weight 7.9 15.2 --Ca0 % by weight 5.5 5.1 3.0 -Fe % by weight 10.0 0.70 --Fe0 % by weight 34.4 20.1 --Fe203 % by weight 31.7 46.7 90.6 -Mg0 % by weight 1.69 1.1 0.36 -Mn0 % by weight - 0.10 0.17 -K + Na % by weight 0.15 0.24 0.04 -C1 + F % by weight 0.80 0.13 --Pb + Zn % by weight 0.30 1.7 0.01 -Si02 % by weight 3.13 3.6 4.0 -S % by weight 0.15 0.10 0.05 -P % by weight 0.15 0.10 0.05 The partially reduced iron was then fully reduced and partially melted in the reduction furnace with 182 kg/t of coal and 36 m3/t (s.t.p.) of oxygen. The amount of delivery air for the solids blown in through lances or nozzles was 45 m3/t (s.t.p.). The current consumption of the furnace was 320 kwh/t.
576 kg/t of molten metal, 130 kg/t of slag and a dedusted off-gas quantity of 12,140 m3/t (s.t.p.) were obtained. 24 kg/t of heavy-metal-containing dust was separated out of the off-gas. Furthermore, 737 kWh/t of current were generated by utilizing the waste heat in a steam generator.
The composition of the molten metal, of the slag, of the off-gas and of the separated dust is given in Table 2. Examples 2 and 3 resulted in product compositions which lay within the same range.
Table 2 Molten metal -C % by weight 2.0 - 3.0 -Mn % by weight < 0.2 -Si % by weight 0.1 - 0.2 -S % by weight < 0.09 -P % by weight < 0.08 Slag -Fe0 % by weight 3.0 - 6.0 -Ca0 % by weight 38 - 44 -Si02 % by weight 30 - 36 -Mg0 % by weight 7.0 - 12 -A1203 % by weight 5.0 - 10 Off-gas -C02 % by volume 6.5 - 7.5 -02 % by volume 16 - 17 -Hz0 % by volume 1.0 - 1.5 -Nz + Ar % by volume Remainder Dust -Fe0 % by weight 30 - 75 -Zn0 % by weight 5 - 50 -Pb0 % by weight < 5.0 -Si02 % by weight < 5.0 -Ca0 % by weight < 7.0 Example 2:
A quantity of 1000 kg/h of iron-containing and heavy-metal-containing remainder materials and iron ore - the composition of the charge mixture is given in Table 1 -with 56 kg/t of coal was introduced into the melting cyclone by means of 106 m3/t (s.t.p.) of delivery air and was made turbulent using 270 m3/t (s.t.p.) of oxygen. 5.1 m3/t (s.t.p.) of fuel gas were supplied.
The amount of reducing agent (coal) introduced into the furnace was 151 kg/t, the amount of oxygen was 30 m3/t (s.t.p.) and the amount of delivery air was 38 m3/t (s.t.p.). The current consumption was 268 kWh/t.
480 kg/t of molten metal, 125 kg/t of slag, 11,900 m3/t (s.t.p.) of dedusted off-gas and 36 kg/t of heavy-metal-containing dust were obtained. The current production was 684 kWh/t.
Example 3:
The charge product used was 1000 kg/h of iron ore (composition: Table 1) with 290 kg/t of coal and 136 m3/t (s.t.p.) of delivery air. Furthermore, 336 m3/t (s.t.p.) of oxygen and 55 kg/t of lime were introduced into the melting cyclone. The amount of fuel gas was 6.5 m3/t (s.t.p. ) .
To reduce the iron, 197 kg/t of coal were fed to the furnace with 49 m3/t (s.t.p.) of delivery air and 38 m3/t (s.t.p.) of oxygen. The current consumption was 348 kWh/t.
The products obtained were 625 kg/t of molten metal, 139 kg/t of slag, 15,760 m3/t (s.t.p.) of dedusted off-gas and 22 kg/t of dust. 945 kWh/t of current were generated.
Claims (26)
1. A process for utilizing iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore, characterized by the combination of the following features:
- the remainder materials and, if appropriate, the iron ore are introduced into a melting cyclone (1) with return flow, - reducing agents and oxygen are additionally introduced into the melting cyclone (1) and are made turbulent, - in the melting cyclone (1), iron is reduced at least to FeO, - in the melting cyclone (1), heavy metals are reduced to form metals and are converted into the gas phase by vaporization, - the resulting gas, which may contain heavy metals, the partially reduced iron and the slag are transferred into a directly coupled furnace (5), - electrical energy is supplied to the furnace (5), - reducing agents and oxygen or oxygen-enriched air are introduced into the furnace (5), - iron is fully reduced and partially melted in the furnace (5), and - the vaporized heavy metals are precipitated outside the furnace (5).
- the remainder materials and, if appropriate, the iron ore are introduced into a melting cyclone (1) with return flow, - reducing agents and oxygen are additionally introduced into the melting cyclone (1) and are made turbulent, - in the melting cyclone (1), iron is reduced at least to FeO, - in the melting cyclone (1), heavy metals are reduced to form metals and are converted into the gas phase by vaporization, - the resulting gas, which may contain heavy metals, the partially reduced iron and the slag are transferred into a directly coupled furnace (5), - electrical energy is supplied to the furnace (5), - reducing agents and oxygen or oxygen-enriched air are introduced into the furnace (5), - iron is fully reduced and partially melted in the furnace (5), and - the vaporized heavy metals are precipitated outside the furnace (5).
2. The process as claimed in claim 1, characterized in that the reducing agents are introduced in solid, liquid or gaseous form.
3. The process as claimed in claim 1 or 2, characterized in that coal or carbon-containing waste materials are used as reducing agents.
4. The process as claimed in one or more of claims 1 to 3, characterized in that the reducing agents (which at least in part are formed by fine particles) and/or the oxygen are introduced into the furnace (5) via below-bath blowing nozzles (12).
5. The process as claimed in one or more of claims 1 to 4, characterized in that the reducing agents and/or the oxygen are introduced into the furnace (5) via a lance (15) which is immersed in a slag layer (8).
6. The process as claimed in one or more of claims 1 to 5, characterized in that the electrical energy is introduced into the furnace (5) via a direct arc.
7. The process as claimed in one or more of claims 1 to 6, characterized in that iron and slag are tapped off separately from the furnace (5) via tapping holes (9 and 10).
8. The process as claimed in one or more of claims 1 to 7, characterized in that the heavy-metal-containing gas is afterburned directly at the gas outlet and, in the process, the heavy metals are brought into a solid, oxidic form and are then separated off.
9. The process as claimed in one or more of claims 1 to 8, characterized in that the off-gas is extracted from the furnace (5), and the heavy-metal-containing gas is introduced into the extracted off-gas.
10. The process as claimed in one or more of claims 1 to 9, characterized in that heat from the melting cyclone (1) is used to evaporate cooling water.
11. The process as claimed in one or more of claims 1 to 10, characterized in that heat from the furnace (5) is used to evaporate cooling water.
12. The process as claimed in one or more of claims 1 to 11, characterized in that off-gas from the furnace (5) is afterburned together with the heavy-metal-containing gas and is then cooled, during which process a water used for cooling is evaporated.
13. The process as claimed in one or more of claims 1 to 12, characterized in that the iron-containing remainder material used is fine ore, in particular with a fraction of ultrafine particles, preferably originating from iron ore beneficiation and/or the fines from a pelletizing operation.
14. A plant for utilizing iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore, using the process as claimed in one or more of claims 1 to 13, characterized by the combination of the following features:
- a melting cyclone (1) which has a bottom opening (3) with a constriction and feeds for iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore and for reducing agents and oxygen which open into the melting cyclone (1), - a furnace (5) with a feed for electrical energy, - feeds for feeding reducing agents and oxygen or oxygen-enriched air into the furnace (5), and - an off-gas line which leads out of the furnace (5) to a precipitation device for heavy-metal-containing gas escaping from the furnace (5).
- a melting cyclone (1) which has a bottom opening (3) with a constriction and feeds for iron-containing and heavy-metal-containing remainder materials and, if appropriate, iron ore and for reducing agents and oxygen which open into the melting cyclone (1), - a furnace (5) with a feed for electrical energy, - feeds for feeding reducing agents and oxygen or oxygen-enriched air into the furnace (5), and - an off-gas line which leads out of the furnace (5) to a precipitation device for heavy-metal-containing gas escaping from the furnace (5).
15. The plant as claimed in claim 14, characterized in that the furnace (5) is equipped with at least one electrode (11, 11', 11") which projects into the furnace (5).
16. The plant as claimed in claim 14 or 15, characterized in that the furnace (5) is provided with blowing nozzles (12) for reducing agents and/or oxygen, which are at least partially below the level of the metal bath in the furnace (5) and to which feeds for reducing agents and/or oxygen lead.
17. The plant as claimed in one or more of claims 14 to 16, characterized in that the furnace (5) is provided with openings for lances (15) for blowing in reducing agent and/or oxygen.
18. The plant as claimed in one or more of claims 14 to 17, characterized in that a feed (16) for a coarse fraction of a reducing agent or remainder material opens into the furnace (5).
19. The plant as claimed in one or more of claims 14 to 18, characterized in that a tapping hole (9) for iron and a tapping hole (10) for slag are provided in the furnace (5).
20. The plant as claimed in one or more of claims 14 to 19, characterized in that a connecting line (6) is arranged between the bottom opening (3) of the melting cyclone (1) and the furnace (5).
21. The plant as claimed in one or more of claims 14 to 20, characterized in that an intermediate chamber (20), which if appropriate is in the form of an off-gas line, is arranged on a wall (13) of the furnace (5), into which intermediate chamber the connecting line (6) which connects the bottom opening (3) to the furnace (5) opens.
22. The plant as claimed in one or more of claims 14 to 21, characterized in that the off-gas line from the furnace (5) opens into a heat exchanger, preferably into a steam boiler (17).
23. The plant as claimed in claim 22, characterized in that a hot-air line leads from the heat exchanger to a dryer (23), to which sludge is fed, which sludge, in the dried state, can be fed to the melting cyclone (1) as remainder material via a transport line.
24. The plant as claimed in one or more of claims 14 to 23, characterized in that the melting cyclone (1) is equipped with a cooling device, preferably with an evaporation cooling device.
25. The plant as claimed in or more of claims 14 to 24, characterized in that the furnace (5) is equipped, above the metal level, with a cooling device, preferably an evaporation cooling device.
26. The plant as claimed in one or more of claims 14 to 25, characterized in that an afterburning device (21) for off-gas emerging from the furnace (5) is provided in the off-gas line which leads out of the furnace or at the point where this line opens into the furnace (5).
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT0086599A AT407878B (en) | 1999-05-14 | 1999-05-14 | METHOD AND INSTALLATION FOR RECYCLING RESIDUES AND / OR IRON OIL CONTAINING IRON AND HEAVY METALS |
| ATA865/99 | 1999-05-14 | ||
| PCT/EP2000/002702 WO2000070101A1 (en) | 1999-05-14 | 2000-03-28 | Method and installation with smelting and reduction cyclone and a coupled lower furnace for utilising residual material containing iron and heavy metals and optionally iron ore |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2372809A1 true CA2372809A1 (en) | 2000-11-23 |
Family
ID=3501604
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2372809 Abandoned CA2372809A1 (en) | 1999-05-14 | 2000-03-28 | Method and installation with smelting and reduction cyclone and a coupled lower furnace for utilising residual material containing iron and heavy metals and optionally iron ore |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP1194596A1 (en) |
| AT (1) | AT407878B (en) |
| BR (1) | BR0010527A (en) |
| CA (1) | CA2372809A1 (en) |
| WO (1) | WO2000070101A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109395496A (en) * | 2018-12-19 | 2019-03-01 | 曲靖云能投新能源发电有限公司 | A kind of gas cleaning of garbage incinerating power plant and afterheat utilizing system |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3220083A1 (en) * | 2016-03-16 | 2017-09-20 | Linde Aktiengesellschaft | Treatment of particulate waste |
| EP3220084A1 (en) * | 2016-03-16 | 2017-09-20 | Linde Aktiengesellschaft | Treatment of particulate waste |
| CN109880955B (en) * | 2019-04-17 | 2021-01-08 | 中国恩菲工程技术有限公司 | Smelting method and smelting device for treating iron-based multi-metal ore material in short process |
| CN114623689B (en) * | 2022-03-09 | 2023-11-03 | 江苏沙钢集团有限公司 | Environment-friendly energy-saving electric furnace and use method thereof |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB827957A (en) * | 1955-03-15 | 1960-02-10 | British Iron Steel Research | Improvements in the production of metal from ores and in apparatus therefor |
| DE3536635A1 (en) * | 1985-10-15 | 1987-04-23 | Kloeckner Humboldt Deutz Ag | Process and equipment for recovering especially iron as well as zinc, lead and other non-ferrous metal constituents from oxide materials of high iron content |
| DE3607774A1 (en) * | 1986-03-08 | 1987-09-17 | Kloeckner Cra Tech | METHOD FOR TWO-STAGE MELT REDUCTION OF IRON ORE |
| DE3608005A1 (en) * | 1986-03-11 | 1987-10-01 | Dornier System Gmbh | Process for disposing of special waste |
| DE3729798A1 (en) * | 1987-09-05 | 1989-03-16 | Kloeckner Humboldt Deutz Ag | DEVICE FOR PREVENTING FUSIBLE SUBSTANCES, ESPECIALLY ORE CONCENTRATES |
| US5228901A (en) * | 1991-02-25 | 1993-07-20 | Idaho Research Foundation, Inc. | Partial reduction of particulate iron ores and cyclone reactor |
| DE4124101C2 (en) * | 1991-07-18 | 1994-06-09 | Peter Dr Koecher | Process for inerting solid residues, especially from waste incineration and flue gas cleaning |
| DE4439939A1 (en) * | 1994-11-09 | 1996-05-15 | Kloeckner Humboldt Deutz Ag | Process for the thermal disposal of residues |
| NL9500600A (en) * | 1995-03-29 | 1996-11-01 | Hoogovens Staal Bv | Device for producing liquid pig iron by direct reduction. |
-
1999
- 1999-05-14 AT AT0086599A patent/AT407878B/en not_active IP Right Cessation
-
2000
- 2000-03-28 CA CA 2372809 patent/CA2372809A1/en not_active Abandoned
- 2000-03-28 WO PCT/EP2000/002702 patent/WO2000070101A1/en not_active Application Discontinuation
- 2000-03-28 BR BR0010527A patent/BR0010527A/en not_active Application Discontinuation
- 2000-03-28 EP EP00920595A patent/EP1194596A1/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109395496A (en) * | 2018-12-19 | 2019-03-01 | 曲靖云能投新能源发电有限公司 | A kind of gas cleaning of garbage incinerating power plant and afterheat utilizing system |
| CN109395496B (en) * | 2018-12-19 | 2020-11-10 | 曲靖云能投新能源发电有限公司 | Flue gas purification and waste heat utilization system of waste incineration power plant |
Also Published As
| Publication number | Publication date |
|---|---|
| BR0010527A (en) | 2002-02-19 |
| AT407878B (en) | 2001-07-25 |
| EP1194596A1 (en) | 2002-04-10 |
| WO2000070101A1 (en) | 2000-11-23 |
| ATA86599A (en) | 2000-11-15 |
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