DE2165595A1 - Sintered agglomerate and process for its manufacture - Google Patents

Description

VATiNTANWJ (ITI DR. E. WIEGAND DIPL-ING-W. NO MAN 9 1 C C C Q C DR. M. KOHtER DIPL-ING. C GERNHARDT Z I O O 3 3 α MONKS HAMIUtO PHONE. 55547 «8000 MÖNCHEN 15, TELEGRAMS) KAIiATENT NUiSIAUMSTRASSE 10

December 30, 1971 W 40 931/71

Showa Denko Kabushiki Kaisha
Tokyo (Japan)

Sintered agglomerate and process for its manufacture

The invention relates to a sintered agglomerate that is used in the Production of a chromium-containing ferro-alloy can be used; the invention also relates to a method of manufacture this sintered agglomerate.

When chromite ore is reduced with carbon, the oxides of chromium and iron contained in the ore are reduced via an intermediate stage in which the carbides are formed, eventually reaching the metallic state to form a chromium-containing ferroalloy. If one attempts, the chromium-containing ferroalloy n by direct reduction of chromite ore with carbon £ produce an electric furnace, a large amount ßA consumes more expensive electrical energy, with the result that the production costs are extremely high. However, to manufacture the sintered

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Agglomerate in which a substantial part of the ore contained Oxides of chromium and iron, as indicated above, up to the carbide form intermediate has been reduced, cheap fuels such. B. heavy oil, powdered coal and the like. Can be used. if Now subjecting the agglomerates obtained in this way to a final reduction in an electric furnace is the electric one Energy consumption low and it can then be a cheaper alloy product can be obtained.

Consequently, there is ultimately a chromium-containing one in the production Ferroalloy is the practice in using the agglomerates produced as an intermediate product as described above either as a starting material or to use as an add-on. These agglomerates can be made in the following way: A powdery one Mixture of chromite ore and a carbonaceous material is processed into briquettes or pellets, then who & ei / dicsc sintered by roasting with the help of the heat of combustion of a fuel.

A typical example of the previously known sintered agglomerate is, as described in US Pat. No. 2,888,3278, one which is practically uniform and consists essentially of oxides and Carbides of iron and chromium and free carbon, such a composition that about 15 to 40% by weight of the total composition represent bound chromium, of which about 15 to 80% by weight are acid-soluble and the remainder is insoluble in acid, about 12 to 60% by weight of the total composition bound iron represent, of which at least 85 wt .-% are acid-soluble and the The remainder is insoluble in acid containing enough free carbon so that the total carbon content is at least about 5% by weight in excess of that required to achieve a 1 ri-Grama atomic ratio from carbon to oxygen in the aggregate,

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with the remainder carbon and oxygen combined with iron and Chromium in the agglomerate and incidental impurities are there. the end It can be seen from the foregoing description that the agglomerate is substantially uniform and does not have a tough protective coating. If the briquettes or pellets obtained in this way, which are still at a high temperature, are stacked on top of one another, difficulties arise in that the briquettes or pellets fuse together or the chromium or iron which have been reduced to carbides by contact with oxidized again in the air. In addition, due to the fact that the agglomerate contains an excess of free carbon, its mechanical strength and thermal shock resistance are low. As a result, it can be the result of mechanical shocks pulverize in an electric furnace during transportation and thermal shock, with the result that the charge layer gas passing into the electric furnace is inhibited. In addition, the agglomerate melts when it is in Form of a layer is introduced on top of the coke bed layer, which has been piled up as a reduction zone in the electric furnace is, light and passes through said coke bed layer without being completely reduced and falls on the Bottom of the molten slag layer below the coke bed layer, d. H. on the surface of the produced metal layer, which has the consequence that the coordination (equalization) of the furnace conditions is lost and the continuous smooth operation of the furnace cannot be maintained.

In order to circumvent the disadvantages described above, it has already been proposed that to coat the surface of the agglomerate pellets with glue, starch, water glass, pitch or a slag-forming component. However, this has the disadvantage that extra costs for this

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Plating are required to remove the unnecessary impurities increase and that the coating in passage due to the different properties of the coating and that located inside Agglomerate material can be stripped.

An object of the present invention is to provide a sintered agglomerate indicate that the above-mentioned various disadvantages, as they have the usual sintered agglomerates, does not have. Another object of the invention is to provide a method for producing such a sintered agglomerate.

The invention relates to a sintered agglomerate which consists essentially of carbides and oxides of chromium and iron and incidental impurities and which consists of a dense and tough skin of metal oxides and a core covered by this skin, both the skin and the core contain the same metallic elements with practically the same properties, the agglomerate having such a composition that the ratio Cr / Fe about 1.5 to 4.0, the sum of the total Cr content and the total Fe content about 45 to about 601 des total weight of the agglomerate ·, the content of combined carbon less than the Cr Cesamtgehalt multiplied by 0.099 plus the total Fe content multiplied by 0.092 by weight, wherein about 18 to about 83 wt. -h of the total Cr acid soluble, from about 51 to about 95 weight . -I of all Fe acid-soluble and the remainder of Cr and Fe acid · are insoluble.

Essential feature of the sintered agglomerate according to the invention, which, as stated above, is particularly salient is the fact that it has a thick and tough skin and that it contains no free carbon. Such a sintered agglomerate was before not known.

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The invention also relates to a vehicle for production the above-mentioned sintered agglomerate. This procedure will carried out in the following manner: A chromite ore and a powdered carbonaceous material are mixed with each other mixed so that the Cr / Fe weight ratio is within the range from about 1.5 to about 4.0 and the carbon coefficient is within the range of from about 0.5 to 1.0 so obtained Mixture is pelletized and the green pellets obtained after drying and pre-heating in the presence of excess Oxygen in a high temperature zone of about 1200 to about 1500 ° C, which is generated by the combustion flame of a fuel is introduced, so including overturning essentially is reduced.

The features and advantages of the invention will become apparent from the detailed description below.

One of the essential features of the sintered agglomerate according to the invention is that it has a skin of metal oxides. Since this skin is formed by sintering the chromite ore itself during the roasting stage, it is dense and tough. Also contains they naturally contain the same metallic elements in practically the same proportions as they contain in the core part are. Since the agglomerate has a dense and tough skin made of metal oxides, it is exposed to mechanical or thermal shock during of transport or within the electric furnace into which it is introduced is not broken or pulverized. As a result, those contained in the core after reduction become the carbides Chromium and iron are not reoxidized and the gas passage is also not affected when the agglomerates are introduced into the electric furnace. In this way, the agglomerate according to the invention, if it is still in a state of elevated temperature immediately after its production, transported or for

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the manufacture of the alloy is introduced directly into the electric furnace will. If the agglomerates are introduced into the electric furnace in a state of still elevated temperature, a electrical energy from 500 to 800 KWh per ton of produced Chromium-containing ferroalloys are saved in comparison to the case that the agglomerates only after cooling to room temperature to be introduced. In addition, the metal oxide skin of the agglomerate according to the invention is less fusible than the core part. Therefore, the core part of the agglomerate melts in the lowermost part of the introduced layer, i.e. H. the core parts of the agglomerates in the Contact with the coke bed layer, first and then only gradually does the skin melt. In this way the agglomerates do not flow through the Köksbettschicht and do not fall in one incomplete reduced state to the bottom of the furnace. Therefore, the internal order of the electric furnace is maintained and this not only enables continuous operation of the electrical Furnace, but this also increases the yield ar. target metal alloy greatly increased.

The agglomerate according to the invention is usually almost spherical in shape Pellet with a diameter of about 10 to 30 mm and the metal oxide skin should from the standpoint of ensuring the mecha-) Niche strength and tightness, which is required to prevent the proportion of coke from reoxidation, from a preferred point of view be about 0.2 to about 2 mm thick.

The importance of the various components and their proportions of the agglomerate according to the invention is described in more detail below.

The Cr / Fe ratio defined above and the sum of the total Cr and Fe contents are quantitative ratios obtained by roasting the pellets

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can easily be obtained if one has a single variety or uses a mixture of a number of grades of natural chromite ores. In addition, these proportions are within the Range that is suitable for the production of a chromium-containing ferroalloy that contains the desired amount of chromium contains.

Another essential feature of the agglomerate according to the invention is that it does not contain any free carbon. The amount of the bound (combined) carbon contained therein, ie the carbon present in the form of carbides, is, as defined above, less than (0.099 total Cr + 0.092 total Fe). Although different classes of the carbides of chromium and iron exist, those of the molecular formula Cr_C, and Fe ₇ C _{3 represent} virtually all of them. The amount of the above-mentioned bound carbon contained therein is an amount lower than that calculated from these molecular formulas. The fact that it has not been found to contain any free carbon, together with the fact that it has the skin described above, contributes to the high mechanical strength of the agglomerate according to the invention. In addition, since free carbon is not contained in the agglomerate, the amount of additional carbonaceous material required for the final reduction of the oxides of Cr and Fe in the agglomerate in the electric furnace for making the alloy can be increased, with the result has that the coke bed layer can be made thicker. This ensures the stability of the continuous furnace operation.

In the agglomerate according to the invention, the chromium and the iron are each formed in an acid-soluble and in an acid-insoluble form. The term "acid-soluble" and "säureunlöslich ¹¹ refers to the degree of solubility of the material

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in aqueous sulfuric acid. The acid-soluble forms are primarily carbides and the acid-insoluble forms primarily oxides. The above-defined range of the amounts of these forms of chromium and iron present in the agglomerate is subject to the change in the composition of the chromite ore used as the starting material and the amount of carbonaceous material added to make the pellets. The incidental impurities contained are those metal oxides other than those of chromium and iron contained in the starting chromite ore, e.g. B. SiO ₂ , Al ₂ O. ,, MgO and CaO. The amounts of these oxides vary depending on the type of starting chromite ore.

The method for producing the sintered agglomerate according to the invention is described in more detail below. The procedure was already described in general above, its special outstanding condition is that the amount of the powdery Chromite ore to be mixed carbonaceous material is far less than the usual method. The invention differs fundamentally from the prior art in this respect. The chromite ore and the carbonaceous material, which are suitably used are those which are cut to a size below, for example, 147 microns (less than 100 mesh) have been finely chopped. Coke becomes useful because of it Purity used as a carbonaceous material, however, it can also anthracite or other carbonaceous materials with a low ash content and volatile components individually or used as a mixture of two or more of them.

The amount of the carbonaceous material used is limited to a carbon coefficient of 0.5 to 1.0. Of the As used herein, the term "carbon coefficient" means one

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Number representing the ratio of the amount of carbon used to the stoichiometric amount of carbon required to reduce the total amount of chromium and iron oxides contained _{in the chromite ore in the form of Cr 7} CL and Fe ₇ O _3. By mixing the carbonaceous material in a smaller proportion than the stoichiometric amount, the pelletized agglomerates become so strong that they are hardly pulverized during the drying, preheating and roasting steps, thereby not only causing the abnormal formation of congestion rings of the molten agglomerates, which are used to shut down the Roasting of the agglomerates used in the rotary oven is prevented, but also as a result of which the agglomerates are pulverized to a size of less than 5 mm during the subsequent operation of the electrical

Oven is kept to a minimum, a process common to the latter Operation avoided four musts, so as to the furnace operating conditions to stabilize.

On the other hand, the reason is that in spite of the smaller amount of carbonaceous Material a reduction rate can be achieved which is favorable in comparison with that in the conventional method or even higher that a suitable combination of roasting temperature and oxidizing atmosphere is used. If the Carbon coefficient is below 0.5, the reduction rate will be the chromium and bisene oxides are low and the economic value of the sintered agglomerate suffers.

As the binder to et \ v ^T a 6% bentonite to the starting material in the above amount ratio can be added, for example etiva. 2 Then a small amount of water is sprayed onto the mixture, after which the mixture becomes pellets with an almost spherical shape with a diameter of about 10 to 30 mm with a

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Deformed granulating device. Can be used as binders Bentonite, water glass and pulp waste liquid. These can be used singly or in combinations of two or more of them.

The green pellets thus obtained are then dried with, for example, a net-type dryer; this is followed by the Preheating the dried pellets on. The heat consumed in the roasting stage is advantageously used in the preceding drying

»And pre-heating stages are used. When preheating with the help a shaft furnace is carried out in which the waste heat of the rotary furnace used for roasting is used the possibility of oxidation loss of the carbonaceous material present in the pellets caused by water vapor and Carbon dioxide is produced. In order to keep this loss to a minimum, the temperature should therefore preferably be at a value of not more than 60Ö C. If the preheating is carried out with a gas, its content of water vapor and carbon dioxide is low, the preheating can be carried out at a temperature up to about 900 ° C.

The preheated pellets are then introduced into excess oxygen (air can also be used) with the introduction of P introduced a zone with a temperature of about 1200 to 1500 C, generated by the combustion flame of a fuel, whereby they are toasted while they are being tumbled. The usual roasting oven is used as the roasting oven. As fuels are Heavy oil, propellant gas, powdered coal, etc. can be used. The reason why excess oxygen when performing the reduction the pellets should be present is as follows:

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In the process according to the invention, the carbon monoxide formed during the reduction of the metal oxides with the carbon-containing material is mixed with oxygen or air, which are necessary for converting the carbon monoxide into carbon dioxide by further combustion of the same, whereby an oxidizing atmosphere at an elevated temperature is formed. In this V / else, the pellets are subjected to the influence of the oxidizing atmosphere and the oxidation takes place at its surface to form an oxide skin before they reach the zone of elevated temperature, for example 130o C ⁰ on the same. Characterized this oxide skin, together with its Kompakticren rusting even denser and tougher in the zone with an elevated temperature above 13Of ^"1 C. Since this oxide skin itself forming dense and tough., The interior of the pellets through the oxidizing atmosphere of the furnace is As a result, the chromium and iron components within the pellets, which have once been reduced to carbides, are not subjected to back oxidation In addition, there is also an effect that the pulverization phenomenon observed when a large amount of the carbonaceous material is added can be controlled Making the alloy can be maintained by completing the reduction of the sintered pellets introduced into an electric furnace. In addition, the method according to the invention has notable economic advantages, since the sintered pellets can be introduced into the electric furnace while they are still in the elevated temperature state.

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Since the pellets have been thoroughly preheated, they are very resistant to thermal shock and are hardly pulverized as a result, even if they are suddenly introduced into high temperature zones of about 1200 to about 1500 ^° C. inside the rotary furnace.

According to the inventive method is effected in that the pellets, after having been preheated within the rotary kiln successively elevated through the zones temperature of about 1200 to about 1 TiOO ⁰ C, wherein the reduction reaction occurs, and from about 1300 to about 1500 C, the reduction being particularly rapid, changing or being introduced directly into these zones. Since the pellets are exposed to a high temperature under an oxidizing atmosphere, the surface of the PellcLS compacts rapidly and the pellets are covered by a self-forming, dense and tough oxide skin Pulverization, when agitated (shaken) vigorously, is extraordinarily low. The substantial reduction of metal oxides to carbides takes place in the temperature zone from 1200 to 1500 ⁰ C. The term "substantial reduction" means that particular Chrojnoxyd is rapidly and almost completely to its carbide reduces "the substantial reduction of this chromium oxide is a3 .1 best done quickly in the zone of increased Toriperatur 1300-1500 ^0C. "Iiisenoxyd is easily reduced than chromium.

If the sintered pe]] ots obtained in this way are removed from the rotary furnace and stored in a receptacle box, the desired sintered aggregates are obtained. These can be η 1 τ; Output.sj:iat.eri ί) 1 for the production C ¹ Cr containing chromium ■ ;: alloy immediately while still ho K. i-ind, ο '-! Er nach de, Ί! 'jihl'iv.

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be introduced into the electric furnace. As in the case of the sintered agglomerates obtained by the process according to the invention the preheated agglomerates are suddenly exposed to an oxidizing atmosphere at an elevated temperature, as indicated above, a strong compaction occurs due to the roasting with the formation of a dense and tough oxide skin. It therefore practically does not occur Reoxidation of the carbides of chromium and iron, the reduction products formed inside the above-mentioned sintered agglomerates even if they are exposed to the open air after being removed from the rotary oven.

The following examples are intended to demonstrate the inventive method as well explain the sintered agglomerates obtained and their use in more detail, but without restricting them to them.

example 1

Manufacture of sintered agglomerates

Chromite ores of various types of the qualities given in Table I below were each finely ground until more than 90% of the particles were less than 100 microns in size and 448 kg of chromite ore from the Philippines, 70 kg of Indian chromite ore and 482 kg South African chromite ore, totaling one ton, was thoroughly mixed with 189 kg (corresponding to a carbon coefficient, as defined above, of 0.85) powdered coke and 39.2 kg powdered bentonite. After spraying about 1% Lasser on this mixture, the mixture was pelletized with a pan-type pelletizer while spraying more water to form about 1400 kg of spherical pellets about 10 to 30 mm in diameter. That

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The chromium / iron ratio in the pellets was 1.97. The above pellets were dried for 40 minutes in a Ne tz-type dryer, with a stream of air having a maximum temperature of 250 ° C gelling through:
0.5%.

of 25O ° C was passed through to the Residfeuclitigkeit to about

The dried pellets were immediately transferred into a pre-heater that pre-heating was carried out in the manner that was passed at about 600 ⁰ C by a heat exchanger through the preheater, the exhaust gas from the rotary kiln to the reduction of the gas temperature.

Heavy oil was used as fuel in the rotary furnace, the zone of the highest temperature of the same was kept at 1470 ° C, while excess air was introduced to complete the combustion of the fuel and the formation of carbon monoxide.

The above preheated pellets were inserted into the loading end of the rotary furnace and while rotating, was causes them to pass through the high temperature zone with the above "Temperature happened to effect its substantial reduction, then they were allowed to migrate to the discharge end of the furnace where they were withdrawn into a receiving box for the sintered pellets. The composition of the sintered agglomerate thus obtained became analyzed, the results given in Table II below being obtained.

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Table I.

Qualities of Chromite Ores and Coke

Components (%)

Art

Chromite ore mined in the Philippines

Chromite ore mined in India

Chromite ore mined in South Africa

FeO

^M S ° ^Si0 2

49.30 17.88 11.98 15.14 3.04 0.3

53.73 13.57 11.90 9.78 5.09 0.3

44.16 24.43 15.79 10.31 2.95 O _f 27

Carbonaceous material

Component n_

carbon

volatile ash constituents

coke

87.0

2.2 10 _t 8

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Table II

Composition of the sintered agglomerate

Molar ratio of the metallic composition (ξ) elements

Components total i skin , 97% core skin core Total cr 34.6 52 30.0 , 2 % 35.0 1.00 1.00 Acid Soluble Cr 20.0 58 0 , 0 % 22.8 - - Total Fe 17.6 86 15.5 , 0- % 17.9 0.48 0.47 Acid soluble Fe 15.2 0 17.3 - - Bound total-C 2.8 0.04 3.14 ■ - - MgO 12.8 11.3 13.2 ' 0.49 0.49 Al ₉ O, 15.3 13.8 16.5 0.47 0.48 SiO ₂ 6.7 5.9 7.4 0.17 0.18 Total Cr / total Fe Total Cr + Gosamt Fe Soluble Cr / Total Cr Soluble Fe / Total Fe Other characteristics

Skin thickness average 0.8mm (0.5 ~ 1.1mm) Compressive strength on average 65 kg / pellet (43-86 kg / pellet)

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Manufacture of the alloy

The sintered pellets described above were, while still at an elevated temperature (about 1000 ⁰ C) were mixed with lump coke and silicon dioxide and limestone as a flux, the mixture was introduced into an electric furnace and the melting operation was carried out, with the results given below received:

1000 kg of the sintered pellets described above, 84 kg of silicon dioxide, 115 kg of limestone and 95 kg of lump coke were used as starting materials in an electric 4000 KW Siemens-Martin-Ofer> introduced for the production of high carbon ferrochrome and the furnace conditions were monitored so that during operation the required data has been received. As a result, the following facts worth mentioning were obtained.

(1) The sintered pellets in the material layer kept their original shape even at a high temperature without that they were pulverized by the thermal shock until they fell into the molten reaction layer;

(2) despite the fact that the sintered pellets are in the material layer exposed to a high temperature, there was almost no reoxidation of the metallic chromium and iron present in the core of the pellets were observed;

(3) the pellets fell one by one from the lower part of the material layer into the molten reaction layer and there was no partial melting or splashing of the slag around the Electrodes around on. The electrical energy consumption in this case was UiSO KV.'h / ton. (When using the surgery from common sintered pellets in the same way

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and manner was carried out, the electric power consumption was about 3700 Klvh / ton). That with this oven treatment The metal obtained is given in Table III below. The chromium recovery from this furnace treatment was about 93%.

Table III Composition of the chromium-containing ferro-alloy

Components (%)

Cr Fe Si

57.4 31.2 2.2 8.4

Example 2

Manufacture of sintered agglomerates

Chromite ores of the types given in Table I of Example 1 were each finely ground to more than 935 of the particles Less than 10 microns in size and 603 kg each Chromite ore mined in the Philippines and 397 kg of one mined in India Chromite ore, a total of one ton, weighed 211 kg (corresponding to a carbon coefficient of 0.95) more powdery Coke and 4 3 kg bentonite mixed and then as in the example 1 to almost spherical pellets with a diameter of Granulated about 12 to 26 mm, while V / water is sprayed onto the mixture became. The total weight of the pellets obtained was

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1430 kg. The chromium / iron ratio of the pellets was in this Trap 2.75. As in Example 1, these pellets were then dried, preheated, and then placed in a maximum temperature A rotary furnace maintained at 1455 ° C. was introduced, in which the reduction of these pellets was carried out with circulation. The composition of the sintered agglomerates thus obtained is given in Table IV below.

Table IV

Composition of the sintered agglomerate

Composition (%)

Molar ratio of metallic elements

Components total 2 skin , 75S Interior skin Interior (O _f 8-4 _r 4 mm) Total cr 36.3 49 33.2 r e.
, D 'o 37.2 1.00 1.00 Acid Soluble Cr 24.0 66 0 , 2% 31, 2 - - Total Fe 13.2 75 12.1 .8th% 13.5 0.34 0.34 Acid soluble Fe 10.0 0 13.0 - - Bound total-C 4.4 0.07 4.4 - - MgO 13.7 12.4 14.1 0.48 0.49 Al ₂ O ₃ 13.8 12.7 14.1 0.39 0.38 SiO ₂ ■ 7.9 7.0 8.0 0.18 0.19 Ge s am t - Cr / Ge s anit - Fe Others Characteristics : Gesar.it-Cr + Ges; : t-Fe Soluble Cr / Total, nt-Cr Skin thickness Solve 1 i ch ο 5 Fe / Ge .s a in t - Fe you r ch s chn i 111 i ch 1.1 mm

Compressive strength average 74 kg / pellet (60-88 kg / pellet)

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Manufacture of the alloy

The sintered pellets thus obtained were coated with lump coke as in Example 1 while still at a high temperature and silica mixed, then the mixture was introduced into an electric furnace and the melting process was carried out, the results given below were obtained.

82 kg of piece coke and 83 kg of silicon dioxide are trarden with 1000 kg of the above-mentioned sintered pellets mixed at elevated temperature and the mixture was poured into an electric 4000 KW Siemcus-Martin Furnace introduced for the production of high carbon ferrous chromium.

Stable furnace operation was maintained without any gas or slag splashing on the surface of the material layer. The composition of the alloy obtained is given in Table V below. The electrical energy consumption in this The mode of operation was 1920 KWh per ton of alloy, a value that represents about half of the normal consumption. In addition, fraud the yield of chromium in the electric furnace was about 94.3%.

Table ¥
Composition of the alloy

Components (ξ)

Cr Fe Si

65.9 25.2 1.4 6.4

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Claims (1)

Claims Sintered agglomerate consisting essentially of carbides and Oxides of chromium and iron and incidental impurities, characterized in that the agglomerate consists of one dense and tough skin consists of metal oxides and a core covered with this skin, whereby both the skin and the core contain the same metallic elements in practically the same proportions that the agglomerate one has such a composition that the ratio Cr / Fe is about 1.5 to about 4.0, the sum of the total Cr content and the total Fe content about 45 to about 60% of the total weight of the agglomerate, the bound carbon content is less than the total Cr content multiplied by 0.099 plus the total Fe content at 0.092, with about 18 to about 83% by weight of the total Cr being acid soluble, about 51 to about 95% by weight of the total Fe acid soluble and the remainder of Cr and Fe are acid insoluble. A method for producing the sintered agglomerate according to claim 1, characterized in that chromite ore and powdered carbonaceous material are mixed together so that the Cr / Fe weight ratio is within the range of about 1.5 to about 4.0 and the carbon coefficient is within the range of about 0.5 to 1.0 that the resulting mixture is pelletized and that the green pellets obtained after drying and preheating in the presence of excess oxygen in a high temperature zone of about 1200 to about 1500 C, which is generated by the combustion flame of the fuel will be introduced so that they are substantially reduced with rotation. 2098337D6A1 BAD ORfOINAL