CN1389699A - Ore-smelting furnace suitable for producing RE ferrosilicon alloy through one-step process - Google Patents

Abstract

This invention relates to an ore-smelting electric furnace of electric power below 2000kva, which is suitable to one-step production of rare earth ferrosilicon alloy. A pole center circular formed by three electrodes and with the electric power per unit area not less than 1500kva is set in the furnace eccentrically to the direction of the iron-tap hole, one of the poles is opposite to the iron-tap hole. Said invention can solve the problem of furnace base rising, largely reduce the production cost.

Description

Be applicable to the hot stove in ore deposit of producing RE ferrosilicon alloy through one-step process

The present invention relates to a kind of hot stove in ore deposit that is used to smelt insoluble metal, particularly relate to a kind ofly with big current low voltage, electrode inserts direct heating in the furnace charge, the smelting mine heat furnace that be applicable to producing RE ferrosilicon alloy through one-step process of power below 2000KVA.

The traditional method of producing rare earth ferrosilicon alloy is a two step method, and its used smelting device mostly is direct-fired electric arc furnace.Because two step method is produced for being interrupted, used electric arc furnace adopts topples over discharging, thereby does not have the problem of furnace bottom rising.Single stage method rare earth ferrosilicon alloy smelting process of coming out newly developed, because the time is not long, technical also in further exploration, therefore, the smelting device that does not also have supporting design with it in the prior art, mostly being in the practice to adopt was smelting duriron and the hot stove of custom-designed avasite originally, and mostly medium-sized and small enterprises are the hot stove of avasite that adopts 2000KVA following.The hot stove in the ore deposit of this class provides the electrode of high temperature heat source to be generally three electrodes, the utmost point heart circle that the utmost point heart of three electrodes is constituted, and the electric power on its unit surface has only 1300KVA for every square metre.Because the physical and chemical performance of rare-earth mineral is different from silica mine, process at the mine heat furnace smelting rare earth ferrosilicon alloy that uses smelting ferrosilicon, some oxide compound in the rare-earth mineral is not high enough because of smelting temperature, also have little time abundant reduction and just sink to furnace bottom, formed the viscosity height at furnace bottom, the rare earth carbide of mobile difference and complicated silicate, can not discharge out of the furnace with molten iron, cause furnace bottom rising, account for tool burner hearth melting space, until the effective smelting space that accounts at last the tool burner hearth fully, the hot stove in general ore deposit is repaired its life cycle and is had only three months from going into operation to, it is huge that the hot stove in ore deposit is repaired a financial loss, even adopt reparation not thorough, also can bring environmental pollution with ferric oxide, Wingdale is the method prepurging of cleaning medium, and reparation financial loss once is also more than tens0000 yuan, as adopting the fried method reparation of explosive, reparation financial loss once is especially up to more than the hundreds of thousands of unit, but also dangerous, increase thereby be directed at production cost, economic benefit reduces.

The objective of the invention is short at prior art, and provide a kind of furnace bottom rising that can not produce, the hot stove in the ore deposit applicable to producing RE ferrosilicon alloy through one-step process that production cost is low.

Can realize that the foregoing invention purpose is used for the hot stove in ore deposit that rare earth ferrosilicon alloy is smelted, mainly comprise furnace body shell, be positioned at the intravital wall lining layer of shell, the iron notch of design on furnace body wall, what be connected with power supply can axially insert and withdraw from the inner of the boiler chamber material up and down, be used to provide the electrode of high temperature heat source, electrode has 3, and electrode becomes equilateral triangle to arrange on the circumference of the utmost point heart circle that its utmost point heart constitutes.It is characterized in that utmost point heart circle that the utmost point heart by electrode constitutes is the every square metre of utmost point heart circle that is not less than 1500KVA of electric power on the unit surface.

The position of above-mentioned said utmost point heart circle in burner hearth can make it be partial to the iron notch direction, and makes electrode iron notch vis-a-vis.These technical measures of the present invention can make burner hearth have higher temperature near the space of iron notch, can make the mobile raising of the molten iron that is positioned at this place, space, are convenient to molten iron and discharge out of the furnace, thereby can prevent furnace bottom rising.Utmost point heart circle is partial to the distance of iron notch direction in burner hearth, be preferably in 40mm～120mm scope.Eccentric too small, do not reach purpose of design, the eccentric too high damage door structure of conference Yin Wendu of crossing.Eccentric distance is advisable not damage furnace binding.

Above-mentioned said furnace body wall air retaining wall, itself and furnace charge interior contacted one deck are electric insulation layer.This insulation layer can be constructed by fireclay brick.These technical measures of the present invention, furnace wall innermost layer than prior art is the good carbon brick layer of electroconductibility, can stop effectively electric current in the burner hearth and heat by the furnace wall to external diffusion, improved the temperature in the burner hearth, improved the flowability of molten iron in the burner hearth, be convenient to the slag material and in burner hearth, discharge out of the furnace, and then can prevent furnace bottom rising.

Above-mentioned said furnace lining layer can be from outside to inside successively: the housing that prevents metal construction exempts from the destructive elastic layer that expands with heat and contract with cold; prevent the fireclay brick thermal insulation layer of heat to external diffusion; prevent that high temperature from causing the high temperature protection layer by carbon brick structure of damage and fireclay brick insulation layer to body of heater.

The above-mentioned said iron notch that is arranged on the furnace body wall is the iron notch of gate-type structure, and the ratio of the Men Gaoyu gate-width of iron notch is preferably 3: 1.The specially designed gate-type structure of the present invention iron notch than the circular hole formula iron notch of prior art, when furnace bottom goes up in certain scope, still can make molten iron and slag in the stove discharge out of the furnace, and can prolong the life cycle of burner hearth, reduces the reparation number of times of burner hearth.

The present invention has also taked some other technical measures.

Designer of the present invention finds in the long-term production practice, in the process that adopts producing RE ferrosilicon alloy through one-step process, the reason that causes furnace bottom rising, the problem that method of compounding furnace charge in production technique exists, the existing questions of smelting furnace own is that the electric thermal power on the round unit surface of the utmost point heart is big inadequately, the temperature of molten bath bottom does not reach enough height in the burner hearth, make that to fall into rare earth carbide and complicated silicate that the rare earths material pelletizing at the bottom of the pond forms mobile poor, can not discharge out of the furnace with molten iron, and be deposited on furnace bottom, and cumulative, promptly cause so-called furnace bottom rising.In the production process that adopts producing RE ferrosilicon alloy through one-step process, if adopt the hot stove in disclosed ore deposit, the method of compounding furnace charge that is applicable to producing RE ferrosilicon alloy through one-step process that is disclosed in another part application for a patent for invention in conjunction with the applicant can overcome the furnace bottom rising problem in the prior art producing RE ferrosilicon alloy through one-step process process fully again.

Disclosed technical scheme is for adopting producing RE ferrosilicon alloy through one-step process technology, both applicable to the hot stove in newly-designed rare earth ferrosilicon alloy ore deposit, also applicable to the hot stove in rare earth ferrosilicon alloy of the prior art ore deposit is transformed.Transformation for the hot stove in existing ore deposit, improve the unit surface electric thermal power on the utmost point heart circle, two kinds of methods are arranged, and a kind of is to keep can improving the electric thermal power on the utmost point heart circle unit surface by the area that dwindles electrode utmost point heart circle under the constant situation of body of heater, electrode, transformer.Another kind method is to keep under the constant situation of the utmost point heart area of a circle, and by changing transformer, the output rating that increases transformer realizes increasing the electric thermal power on the utmost point heart circle unit surface.These two kinds of methods all can obtain good equally effect.Other technologies measure of the present invention, equally both applicable to the hot stove in newly-designed ore deposit, also applicable transformation for the hot stove in existing ore deposit.

The smelting mine heat furnace that in the one-step method production process of rare earth ferrosilicon alloy, adopts the present invention to disclose, the hot stove in the ore deposit of prior art more, owing to overcome furnace bottom rising, can carry out long continuous production, prolonged the repairing efficiency of burner hearth, production cost reduces greatly, can bring huge economic benefit.Produce the hot stove in ore deposit of the prior art of rare earth ferrosilicon alloy, its life cycle generally has only three months, and the burner hearth of the hot stove in ore deposit uses palpus reparation in three months once, could continue after the reparation to produce.And the hot stove in ore deposit is in its life cycle, because furnace bottom rising, furnace cavity is more and more littler, and production efficiency is more and more lower, and the power consumption of unit product increases, and in the latter half of its life cycle, its throughput has only 70% of the production initial stage.Adopt the hot stove in ore deposit of prior art, use the one-period reparation once, can produce following enormous economic loss: (is example with hot ore deposit, 1800KVA ore deposit), 1. the burner hearth reparation must be scrapped the furnace charge of a stove, is worth more than 1.2 ten thousand yuan; 2. the later stage of production cycle is lost about 1.3 ten thousand yuan every day because of the underproduction; 3. because of underproduction power consumption increases, lose about more than 3,000 yuan every day; 4. stop production and the payment rehabilitation expense because of repairing, be about more than 5.1 ten thousand yuan every day.More than every failure costs add up mutually, repair burner hearth once because of furnace bottom rising, financial loss is up to hundreds of thousands of unit.Adopt the hot stove in ore deposit of the present invention, than the hot stove in the ore deposit of prior art, 1 year reduces by twice burner hearth reparation at least, can reduce the financial loss more than more than 50 ten thousand yuan, and economic benefit is very considerable.

Accompanying drawing 1 is a forward sectional structure synoptic diagram of the present invention.

Accompanying drawing 2 is plan structure synoptic diagram of accompanying drawing 1.

Accompanying drawing 3 is that iron notch A in the accompanying drawing 1 is to structural representation.

Below in conjunction with the drawing explanation, provide one embodiment of the present of invention.

Be applicable to the hot stove in ore deposit that the rare earth ferrosilicon alloy single stage method is produced, by the hot furnace shell 7 in ore deposit, be positioned at the intravital air retaining wall of shell, be arranged on the iron notch 8 on the furnace body wall, the electrode 2 that is connected with the transformer output terminal constitutes.The air retaining wall of furnace body wall is a multilayered structure, and ecto-entad is successively: be used to prevent that furnace body shell from exempting from the elastic layer 6 that the destructive that expands with heat and contract with cold is made of sand; Be used to stop the thermal insulation layer 5 by fireclay brick structure of heat to external diffusion; The protection furnace wall exempts from the protective layer 4 by the carbon brick structure that high temperature damages; Be used to stop heat and electric current in the burner hearth 1 to the insulation layer of constructing by fireclay brick of external diffusion.The electrode that is placed in stove petticoat pipe top can axially insert the furnace charge in the burner hearth up and down and withdraw from furnace charge under the driving of drive unit.Design has an iron notch 8 on the body of heater furnace wall, and its structure is the gate-type structure, and Men Gao is 3: 1 with the ratio of gate-width, and physical size is a high 300mm, gate-width 100mm.The operating voltage of electrode is 80～84V, and working current is 13740～13750A, and the diameter of three electrodes is 530mm, becomes equilateral triangle to arrange, the circle that the utmost point heart of three electrodes is constituted is utmost point heart circle 9, and utmost point heart circular diameter is 1260mm.The furnace diameter of body of heater is about 3300mm, and burner hearth is about 1400mm deeply, and utmost point heart circle arranged off-centre in burner hearth is partial to the iron notch direction, and eccentricity is 120mm, and an electrode and iron notch is arranged vis-a-vis.

Claims (7)

1, a kind of hot stove in ore deposit that is applicable to producing RE ferrosilicon alloy through one-step process, mainly comprise furnace body shell (7), be positioned at the intravital air retaining wall of shell, the iron notch (8) of design on furnace body wall, the electrode that is used to provide high temperature heat source (2) that can axially insert and withdraw from the inner of the boiler chamber material up and down that is connected with power supply, electrode has 3, electrode becomes equilateral triangle to arrange on the circumference that its utmost point heart constitutes, and it is characterized in that the said utmost point heart circle (9) that is made of the utmost point heart of 3 electrodes is not less than the utmost point heart circle of 1500KVA for the every side's rice of the electric power on the unit surface.

2, the hot stove in ore deposit that is applicable to producing RE ferrosilicon alloy through one-step process according to claim 1, the utmost point heart that it is characterized in that being made of electrode circle (9) are partial to iron notch (8) direction and are arranged in burner hearth, and electrode iron notch is vis-a-vis arranged.

3, the hot stove in ore deposit that is applicable to producing RE ferrosilicon alloy through one-step process according to claim 2 is characterized in that said utmost point heart circle is partial to iron notch (8) direction 40mm～120mm in burner hearth.

4, according to claim 1 or the 2 or 3 described hot stoves in ore deposit that are applicable to producing RE ferrosilicon alloy through one-step process, it is characterized in that the said intravital air retaining wall of shell that is positioned at, its interior one deck is an electric insulation layer.

5, the hot stove in ore deposit that is applicable to producing RE ferrosilicon alloy through one-step process according to claim 4 is characterized in that the air retaining wall of furnace body wall is followed successively by elastic layer (6), thermal insulation layer (5), high temperature protection layer (4) and electric insulation layer (3).

6, the hot stove in ore deposit that is applicable to producing RE ferrosilicon alloy through one-step process according to claim 5 is characterized in that the said iron notch that is positioned on the furnace body wall is gate-type iron notch (8).

7, the single stage method that is applicable to according to claim 6 is produced the hot stove in ore deposit that rare earth ferrosilicon closes, and it is characterized in that the ratio of the Men Gaoyu gate-width of said gate-type iron notch is about 3: 1.