DE1608186B2 - PROCESS FOR PRODUCING FERROMANGANE OR FERROCHROME WITH MEDIUM OR LOW CARBON CONTENT - Google Patents

Description

The information contained in the sentence is provided examples.)

By the entering of the preheated to at least 700 ⁰ C ore and flux into the molten high silicon-containing silicon alloy between the ore melts and rapid desiliconization of the silicon alloy occurs. The resulting strong heat development can be fully used for the implementation.

The intermediate alloys produced by processes known per se preferably have a silicon content from 4 to 40% in the case of silicomanganese and at least 40% in the case of silicochrome. An advantage of the method of the invention is that in principle by any method Silicon alloy produced directly from production, still in the molten state, i.e. without mandatory Solidify, used to reduce the ore. This is an essential feature of the Invention.

The preheating of the ore-flux mixture takes place in the context of the process of the invention not only for reasons of the heat balance. Rather, the preheating causes the ore to be calcined. For example, the different oxides of a manganese ore are converted into Mn ₃ O ₄ by preheating. In this form the silicon is effectively removed from the intermediate alloy without incurring erosion losses.

When pre-heating to a temperature below 700 ⁰ C unbalanced heat balance and insufficient calcination, the ore can be obtained. When heating to temperatures above the expansion point of the ore and the flux, difficulties arise in handling the mixture.

Burnt and slaked lime or limestone can be used as the flux in the usual way will.

Due to the rapid melting of the ore-flux mixture In the intermediate alloy melt, the reaction can be homogeneous between the vigorous stirring Reaction can be carried out in the liquid state. The implementation is preferably carried out in a watering can, especially a vibrating pan. However, it can also be mechanical or with very good success • be electrically stirred.

The reaction is preferably carried out in the vibrating pan known from US Pat. No. 3,251,681. With an alternating eccentric rotation of the pan, the solids introduced are immediately transferred into the pan read the inside of the melt drawn and mixed with it; thoroughly mixed. This gives you a high vReaction efficiency. The yield of final product based on the added irz-flux mixture is noticeably improved. The required dwell time is also significantly shorter than during use inder agitation method.

The melting of the ore and the refining of the silicon alloy containing hollysilicon takes place in this process Due to the strong heat development during the reaction, so that no external heat supply ■ is required.

The invention is described in more detail below with reference to the drawing. It shows the only one Figure in side view of a shaking ladle according to US-PS 32 51 681.

The process of the invention is preferably carried out in a shaker ladle of the type shown in the figure Kind of done. The pan used for the experiments holds 500 kg of load. The pan will at 92 rpm eccentrically offset with the following sequence: 8 s rotation in the main direction of rotation, 2 s pause and 8 s rotation in the opposite direction. The eccentric radius is 45 mm.

The ores and fluxes used in the examples are listed in Table I in terms of their composition. The manganese ore consists of MnO ₂ , Mn ₂ O ₃ , SiO ₂ , Fe ₂ O ₃ , Fe ₃ O ₄ , CaO, P, K ₂ O, Na ₂ O, Al ₂ O ₃ and MgO. The quantitative analysis data are shown in Table I for the relevant constituents of the ore. The two percent by weight impurities in the slaked lime were not analyzed in detail.

example 1

The pouring ladle shown in the figure and specified above is charged with 30 kg of slaked lime and heated ^{to about 800 ° C. with an oil burner.} At this temperature, 500 kg of manganese ore and 180 kg of slaked lime, which have previously been ^{heated to about 95O 0} C in a drum furnace, are introduced. Then, 400 kg of molten silicomanganese be poured at a temperature of 143o C ⁰ in the so loaded pan. The composition of the silica manganese is given in Table II, the 100% supplement being iron with unavoidable impurities. The feed is continuously stirred for 20 minutes. 570 kg of ferromanganese and 600 kg of slag are obtained. The analytical data are given in Table III. In addition to the analyzed components, the slag essentially also contains Al ₂ O ₃ , MgO, K ₂ O, Na ₂ O and traces of impurities that have not been qualitatively examined. Each of the named four oxides is present in the range of about 2 to 3%. The manganese analysis also records the manganese carried along or discharged in oxidic form, so that the sum of the analytical manganese contents of the ferromanganese and the slag deviates slightly from 100%.

Example 2

560 kg manganese ore and 190 kg of hydrated lime are heated in a Koksschachtofen to about 700 ⁰ C. The preheated mixture is introduced into the still hot pan immediately after the process according to Example 1 has been carried out and after the charge has been discharged. Then 400 kg of molten silicon manganese at a temperature of 14C0 ° C are poured into the pan charged with the mixture. It is shaken for 24 minutes. 450 kg of ferromanganese and 690 kg of slag are obtained. The analysis data of the starting component and the products are shown in Tables 1 to III.

Example 3

Immediately after the process described above in Example 2, 500 kg of manganese ore and 200 kg of slaked lime, which were previously heated ^{to about 700 ° C. in a drum furnace, are added to the still hot pan.} 400 kg of silicon manganese are then poured ^{in at a temperature of 136O 0 C.} The mixture is shaken continuously for 12 minutes. 570 kg of ferroalloy and 490 kg of slag are obtained. The results are shown together with the results of Examples 1 and 2 in Tables I to III.

Table I.

Manganese ore Slaked lime

Contents (percent by weight)

Mn SiO ₂ Fe CaO P CaO

52 6 5 4 0.07

Table II

Example Contents of the molten silica manganese No. (percent by weight)

Mn Si CP

1 67.0 16.2 1.7 0.07 2 62.6 15.3 2.0 0.06 3 63.0 15.2 2.0 0.09

Tabel III Levels of
Mn Ferromanganese
Si (Weight percent)
CP 0.10
0.10
0.12 Content of the slag (percent by weight)
Mn CaO SiO ₂ 34.2
24.9
26.8 28.1
24.5
28.7 CaO / SiOj example
No. 78.6
76.7
75.2 1.2
2.7
1.9 1.6
1.9
2.0 For this 1 sheet 23.0
28.5
22.8 1.20
1.02
0.93 1
2
3 drawings

Claims (2)

1 2 up to 61% manganese and up to 55% chromium, in ferro- patent claims: manganese and ferrochrome preserved, however, significantly higher non-ferrous 1. Process for producing ferro-manganese metal concentrations expected. or ferrochrome with medium or low 5 In the production of high-quality ferromanganese carbon content, thereby marked and ferrochrome, the problem of a good net often occurs that a batch of manganese ore is mixed in the batch. In this context. Chrome ore and flux on a Tempe- hang reference is made to US-PS 32 51 681, from the temperature between 700 ⁰ C and below the Erwei a vigorously mixing vibrating pan is known.
₁₀ Finally, a process is common in which the heated mixture is produced with molten first a silicon manganese with a high silicon content or as an intermediate alloy with a high silicon content and this is added silicon chrome and so on The resulting mixture of intermediate alloy is then violently stirred with a manganese ore. implemented in the presence of a flux in the melt 2. The method according to claim 1, characterized in that _t5 is identified. This reaction is relatively strongly exothermic, with the fact that the ore and the flux with the released heat of reaction, but technically only the silicon alloy in a shaking ladle, cannot be used properly, since the melt is converted into. two layers separate and the reduction of the manganese ore by the silicon as an interfacial reaction 20 expires between the layers of the system. The reaction system must to maintain the re- The invention relates to a method for producing induction heat to be supplied. Besides, it must from ferromanganese or ferrochrome with medium as an intermediate silicon manganese firmly into the or low carbon. second stage to be introduced, so that the The production of such medium- and low-carbon 25 heat content of the silicon manganese is lost. Ferro alloys are therefore still difficult to this day. The object of the invention is to create a rig, since both manganese and chromium on the one hand drive towards the economic production of ferrous difficult to reduce, on the other hand easy to carburize manganese or ferrochrome, whose end products are are. due to a low carbon content and a From the DT-PS 75 320 (1894) a method for ₃₀ high non-ferrous metal content is distinguished.
Production of low-carbon ferromanganese. To achieve this object, the invention provides, known. Thereafter, the manganese ore is first reduced to a batch of a manganese ore or manganese (II) oxide and the resulting redu- chromium ore and flux is then carried into molten ferro-silicon at between 700 ° C and below the softening point . In this process, however, not only is _{the ore-flux mixture heated to 35} point so that the required pre-reduction of the manganese ores and the heated mixture with molten highly siliconized are obtained, but above all ferrocium-containing silicon manganese or silicochromic products are obtained, which a maximum of one and the mixture thus obtained is vigorously stirred,
have a content of 29%. A disadvantage of this According to a development of the Erhndung be the method is also that the entire Manganerz- ₄₀ is formed of ore, the fluxes and the silicon alloy in a slag in the Silicoreduktionsstufe. Vibrating pan implemented. The resulting slag has an extraordinarily high manganese content. Due to the high non-ferrous metal content. The iron content, which is high in manganese, hardly occurs. The process known from DT-PS 75 320 ₄₅ 79%, while the chromium content of the available ferro- (1894) delivers so with relatively chromium can be at least 60 to 70%. The lower manganese yield based on the ore as the final drive does not require any pre-reduction. The slagging product is a ferromanganese with only a relatively small amount of the ores, especially the manganese ores, already containing manganese. for the most part in the manufacture of the silicoman Furthermore, from CH-PS 2 29 886 for the production of 50 goose. The resulting slag has a of ferromanganese and ferrochrome with medium or relatively low manganese content of the order of magnitude Carbon content a reduction process moderately only 6 to 12%. The subsequent known in the high-frequency furnace, in which initially a reduction with silicon manganese resulting slag metallic material, expediently a grain, has a significantly higher manganese content component of the alloy to be produced or this 55, namely a manganese content in the range of 17 itself, being melted. To this melt up to 30%, however, affects the material balance of the then the ore and metallic reduction overall process from that this slag only in averaged added as a mixture. How the previously described sets are formed. In addition, a In addition, known processes, this process also shows that a large part of this slag manganese is still growing in growth the unfavorable feature on that the entire 60 drive is reduced. To be related to the ores Slag from the manganese ore or chrome ore in which high non-ferrous metal yields are achieved in this way. Silicoreduktionsstufe incurred. In particular, those that cannot be used in the formation of silicon manganese or silicon Manganese slag has an inefficient chromium released heat is for the successor high manganese content of 21%. Fully exploitable in terms of procedures. The desiliconization of the the ore will therefore only produce low yields of man- 65 intermediate alloy can in the liquid state with the gan and accordingly achieved chrome. Compared to the rapidly melting ore run smoothly. the Ferromanganese described above are indeed the heat balance of the overall process can be higher Manganese and chromium concentrations, namely lead properly cheap. (The in this ab-