CS260154B1 - A method for obtaining liquid metal from ferro-rays of wreckage - Google Patents

Abstract

The solution concerns a method of obtaining liquid metal from waste ferrotungsten slag or from a mixture with waste ferromolybdenum slag, their remelting combined with reduction in a ferroalloy electric furnace. Remelting is carried out in a covered arc, with carbon electrodes immersed at least 0.5 m in the slag, while a layer of unmelted solid charge is maintained on the surface to prevent the access of the air atmosphere to the molten slag bath and with the help of a submerged carbon electrode, carbon reducing agent, or carbon lining, the low oxygen potential of the slag phase is maintained, with a content of 45 to 55% SiO in the slag, alkalinity according to Machasev up to 1.15 and FeO activity in the slag up to 0.10.

Description

260154

BACKGROUND OF THE INVENTION The present invention relates to a process for obtaining liquid metal from ferro-ferrous heaps by remelting them, coupled with reduction in a ferro-alloy furnace, by a continuous method of covering with a covered arc.

In the production of ferromagnetic material, a rolling pellet is formed containing 0.05 to 3% by weight, depending on the quality of the produced FeW and the production conditions. WO3, rarely also WO3. The remainder consists of MnO, MgO, CaO, FeO, S1O2 and other impurities below 1% by weight. In connection with the price of the W-raw materials, it is expedient to use a mixture of WO3 containing, e.g., greater than 0.3. wt. obtain tungsten by reprocessing them.

Over time, a number of reprocessing processes have been developed to obtain tungsten, which in principle are also useful for the treatment of FeW slags, such as melting with soda followed by water extraction, neutralization and excretion of sodium tungsten. This method, which is most commonly used, requires a relatively expensive batch preparation - the concentrate must pass through a 0.075 mm sieve and a special apparatus. Another method is to process FeW slags from a certain WO3 content, for example, starting from 0.3% WO3, by melting in an electric arc furnace, i.e., a plant in a metallurgical plant, more readily available, with additional reductions in carbon and carbon. a quartz reducing agent, in a continuous manner, with complete melting of the charged feed and tapping of the melt products once. Grain debris sizing jenapr. up to 60 mm. The so-called tiny metal is formed, containing W, FeMn, Si and some other impurities in small quantities. This method can be used without difficulty in producing standard FeW. The disadvantage of this second, commonly used method is that due to the radiation of the exposed bath and the use of the silicon reducer, it is energy-intensive and can only be used on electric furnaces of less than 5 MW, with no carbon lining available. a furnace facilitating the achievement of a low molten slag oxidation potential. These reasons together cause a low level of labor productivity and an increase in the cost and energy intensity of remelting the FeW slag. The braking or even totally impossible reworking of the hitherto generated FeW slag.

These disadvantages are eliminated by the method of obtaining the liquid metal from the ferro-tungsten slag waste from the soda-lime ferro-molybdenum slag mixture associated with the reduction in the ferro-alloy furnace according to the invention. The invention is based on the fact that the remelting is carried out with a covered arc, with carbon electrodes immersed in at least 0.5 m in the top, whereby a layer of unburned solid is maintained on the surface to prevent the access of the air atmosphere of the densified slag bath and by means of a carbonated electrode The carbon reductant, or the carbon lining, maintains the low oxygen potential of the debris phase, at 45-55 [deg.] C. of S1O2 in the slag, the alkalinity according to Machaseva to 1.15 [mu] s of FeO activity in slag to 0.10. The transition from the molten open bath to the overcoat, ie, the process of the invention, is achieved by varying the charge composition depending on the electrical conductivity of the kilometer ageometry by reducing the working secondary electrical voltage so that the electrode ends hurt at least 0.5 m, by continuously feeding a good mixed batch to the batch in small batches according to the melt process, while maintaining the cones 100 to 150 mm by electrodes, periodically tapping the slag and metal without turning off the furnace and finally adjusting the melting temperature of the slag by the coke, quartz , or. the second flux so that a slag of about 50% SiO 2, which is normally bound, is good to tap out of the furnace.

The method of remelting FeW slags to obtain tungsten tungsten metal is characterized by a low oxygen-slag phase which is applicable to ferroalloy furnaces with larger transformers, e.g., 24 MW, and thus higher productivity, and the smaller energy demands of the wol-frame in the wrecked metal. In an exemplary embodiment, a batch weight of 300 kg of FeW slag, 40 kg of stone, 40 kg of quartz, 15 kg of lime, 40 kg of blast furnace slag and 3 kg of Fetries were used. The transformer secondary voltage was 114 to 150 V.

The method can also be used for the obtained ferrous metal from ferro-molybdenum slag in a mixture with ferro-rhumous because the tungsten and molybdenum together with some steels. From the FeW slag, tungsten and iron are selectively reduced, and silicon is only partially manganese, so that the remainder of the slag can serve as a charge for production in the ferroalloy or silicate industry. In the present case, a mixture of rolling FeWross and tungsten feedstocks or molybdenum feedstocks with an increased content of mixtures which can not be used directly for the production of standard ferro-phenol or ferro molybdenum can be used. 2B0154

PREDMEI

A method for obtaining liquid metal from ferro-ferro-slag wreckage, or with a ferro-molybdenum-wreck mixture, by melting it together with a reduction in an electrowinning electric furnace, characterized in that the remelting takes place at a covered arc, with carbon electrodes immersed at least 0, 5 m high, while the surface is

SUMMARY OF THE INVENTION A low oxygen potential of the slag phase is maintained at 45-55% S1O2 in slag, with a low carbon solid electrode, a carbon reductant, or a carbon lining, to prevent access of the atmosphere to the molten slag bath and the submerged carbon electrode. alkalinity under Machasev to 1.15 and FeO activity in slag to 0.10.

Claims (1)

CZECHOSLOVAK SOCIALIST E B P I B A K A (1 ·) * DESCRIPTION FOLLOWS COPYRIGHT CERTIFICATE i260154 (Bl) (51) Int Cl? C 22 B 9/20 (22) Enrolled 04 01 85 (21) (PV 92-85) • 3A0 nto EXCLUSIONS (40) Published 16 05 88 (45) Published 15 04 89 A OILS (75) Author of the Invention PRACNÝ JAROSLAV ing The present invention relates to a method for obtaining a liquid metal from a rolling ferro-raffinated slag from a mixture with a ferro-molybdenum slag, remelting it with a reduction in ferroalloys. The electric furnace, the reflow is carried out with a covered arc, with carbon electrodes immersed in a minimum of 0.5 m in the top, whereby a layer of unburned solid is maintained on the surface to prevent the air atmosphere from entering the molten bath and the submerged coal. The electrode, the carbon reducer, or the carbon lining, maintain a low oxygen potential of the slag phase, with a content of 45 to 55% SiO 2 in slag, alkalinity by Ma chaseva to 1.15 and activity of FeO in slag to 0.10, 260154