KR20150122448A - Apparatus and method for recycling for Magnesia(MgO) using Mg0-C refractories - Google Patents

Abstract

The present invention relates to an apparatus and a method for recycling magnesia-carbon refractories. The apparatus for recycling magnesia-carbon refractories comprises: a central main-pipe housing (10) for supplying a heat source and air; an air suction pipe (60) for sucking air; and a recycling housing (50) in which waste magnesia-carbon refractories exist. The central main-pipe housing (10) includes: at least one or more air inlet pipes (20) formed to introduce external air into the recycling housing (50) through the inside of the central main-pipe housing (10); and a heat source inlet pipe (30) formed to introduced the heat source into the recycling housing (50) through the inside of the central main-pipe housing (10).

Description

FIELD OF THE INVENTION [0001] The present invention relates to a MgO-C refractories,

The present invention relates to an apparatus and a method for recycling a magnesia-carnitic refractory, and more particularly, to an apparatus and a method for recycling a magnesia-carnitic refractory to obtain magnesia (MgO) having a high purity by a method of directly heating a waste magnesia- Recycling apparatus and method.

Conventional methods of recycling waste magnesia-carbonaceous refractories include finely pulverizing waste magnesia-carcass refractories to produce regenerated refractory blocks and the like, and methods of making recycled materials by blending with other raw materials, and rotary indirect heating methods.

Korean Patent Registration No. 10-1105437 recycles waste refractories used as refractory bricks such as converter, electric furnace, and ladle in the steelmaking process and recycles them as raw materials for refractory bricks, It is possible to reduce the consumption and contribute to the improvement of the environment. By classifying the regenerated refractory by the particle size, it is possible to diversify the range of application, thereby providing high-value-added refractory raw materials.

Korean Patent Registration No. 10-0605711 relates to a refractory composition using a waste magnesium carbide refractory material, and includes a constitution of a refractory composition.

Korean Patent Registration No. 10-1135532 relates to an eco-friendly electric furnace filler material, and includes a constitution of a filler material for sealing a ladder of an open-hearth type electric furnace.

Among such conventional techniques, a simple blending method for producing refractory bricks by pulverizing a pulverized refractory is a method in which the pulverized refractory is recycled, and there is a problem that the pulverized refractory can not be recycled as a reusable refractory, The indirect heating method of adding magnesia-caustic refractory to heat the inside of the pipe from inside to outside has not been economical due to high cost and high energy consumption, and also it is difficult to obtain high purity magnesia (MgO) from waste magnesia- There was a problem.

1. Method for regenerating waste MgO-C refractories (Patent Registration No. 10-1105437) 2. The refractory composition using waste metal carbon refractory material (Patent Registration No. 10-0605711) 3. Environmetal friendly EBT filler and manufacuring method thereof (Patent Registration No. 10-1135532)

DISCLOSURE OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a magnesia- And to provide a method and apparatus for recycling carbonaceous refractories.

Further, according to the present invention, the waste magnesia-carbonaceous refractory (MgO-C) is elevated to a predetermined temperature or higher through self-reaction through the supply of air and a heat source so that regenerated magnesia (MgO The present invention also provides an apparatus and method for recycling a magnesia-carbonaceous refractory material.

 In order to accomplish the above object, an apparatus for recycling a magnesia-carbon refractory according to an embodiment of the present invention includes a main main-tube housing 10 for supplying a heat source and air, And a recycled housing 50 in which a waste magnesia-caustic refractory (MgO-C) is present inside the central main tube housing 10 and a central main tube housing 10, At least one air inlet pipe (20) formed for introducing outside air into the recycling housing (50); And a heat source inlet pipe (30) formed to introduce a heat source into the recycle housing (50) through the inside of the central main-tube housing (10); And recycled magnesia (MgO) is obtained by directly heating the air and the heat source introduced into the recycle housing 50 in which the waste magnesia-ka coin refractory is present for a predetermined time.

At this time, after the direct heating, by the self-reaction by the waste magnesia-caustic refractory (MgO-C) formed on the upper part of the perforated plate in the recycle housing 50 according to the method of stopping the inflow of the heat source and continuously introducing air, And the temperature is raised to a temperature higher than the set temperature to obtain regenerated magnesia (MgO).

The predetermined temperature is 700 to 1500 ° C., and the recovered magnesia (MgO) obtained is preferably 80 to 99% in purity.

Also, the central main-tube housing 10 includes a plurality of heat source supply pipes 40 for allowing the heat source to flow into the recycle housing 50 in a structure connected to the heat source inlet pipe 30; And an air nozzle (31) for allowing air to flow into the recycling housing (50); .

Also, the central main-tube housing 10 is a tubular housing vertically placed in a cylindrical shape and has at least one air inlet tube 20 formed at a side thereof symmetrically with respect to a horizontal plane, And a heat source inflow pipe (30) formed between the air inflow pipes (20) by a predetermined angle interval through the outer circumferential surface of the central main tube housing (10).

In order to achieve the above object, according to the present invention, there is provided a method for recycling a magnesia-carnitic refractory, comprising the steps of: supplying outside air from at least one air inflow pipe (20) A first step of introducing the heat source into the central main tube housing 10 through the air inlet tube 20 and the heat source being introduced into the central main tube housing 10 through the heat source inlet tube 30; A second step in which the introduced air and the heat source are introduced into the recycled housing 50 in which the waste magnesia-carbonaceous refractory is present; A third step of performing direct heating in the recycling housing (50) for a predetermined time; .

A fourth step of interrupting the inflow of the heat source through the open / close control of the air inflow pipe 20 and the heat source inflow pipe 30 and continuing inflow of air only after the direct heating in the third step; And a fifth step of recovering magnesia (MgO) by raising the temperature to a predetermined temperature or higher by self-reaction by waste magnesia-caustic refractory (MgO-C) formed on the upper part of the perforated plate in the recycling housing 50. .

At this time, the predetermined temperature in the fifth step is preferably 700 to 1500 ° C.

The apparatus and method for recycling a magnesia-carnitic refractory according to an embodiment of the present invention are characterized in that a high-purity magnesia (MgO) is directly heated to a waste magnesia-carcass refractory (MgO- And the like.

In addition, an apparatus and method for recycling magnesia-carbonaceous refractories according to another embodiment of the present invention is characterized in that waste magnesia-carbonaceous refractory (MgO-C) is self-reacted through air and a heat source, (MgO) having a purity of 80 to 99% at a low energy consumption.

FIG. 1 is a view showing an entire apparatus 1 for recycling a magnesia-carnitic refractory according to an embodiment of the present invention.
2 is a plan view of the magnesia-carnitic refractory recycling apparatus 1 of FIG.
3 is a cross-sectional view showing an incised state of the central main tube housing 10 with respect to the section A-A 'in the magnesia-carbonaceous refractory recycling apparatus 1 of FIG.
4 is a view showing an enlarged state with respect to a region C in the central main-tube housing 10.
Fig. 5 is a view showing air inflow and heat source inflow in the magnesia-carnitic refractory recycling apparatus 1 of Fig. 1;
6 is a flow chart illustrating a method for recycling a magnesia-carbonaceous refractory according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a detailed description of preferred embodiments of the present invention will be given with reference to the accompanying drawings. In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

FIG. 1 is a view showing an entire apparatus 1 for recycling a magnesia-carnitic refractory according to an embodiment of the present invention. 2 is a plan view of the magnesia-carnitic refractory recycling apparatus 1 of FIG.

And FIG. 3 is a cross-sectional view showing an incision of the central main tube housing 10 with respect to the section A-A 'in the magnesia-carbonaceous refractory recycling apparatus 1 of FIG. 4 is a view showing an enlarged state with respect to a region C in the central main-tube housing 10.

Finally, FIG. 5 is a diagram for illustrating air inflow and heat source inflow in the magnesia-carnitic refractory recycling apparatus 1 of FIG.

1 to 5, a magnesia-carbonaceous refractory recycling apparatus 1 includes a central main-tube housing 10 for supplying a heat source and air, a pulverized magnesia-carbonaceous refractory material (MgO- C is present in the recycling housing 50.

The central main-tube housing 10 is a vertically-formed tubular housing having at least one air inlet tube 20 formed at a side thereof symmetrically with respect to a horizontal plane, at least one air inlet tube 20, And a heat source inflow pipe 30 formed on an outer circumferential surface of the central main tube housing 10.

The position and number of the air inlet pipe 20 and the heat source inlet pipe shown in the form of the central main-tube housing 10 or the figure are not limited, and it is desirable to take the concept and role of each constitution as an emphasis. For example, Figs. 1 and 5 show an embodiment of the magnesia-carnitic refractory recycling apparatus 1, which does not necessarily require a heat source and air to be supplied from the lower end of the recycled housing 50. The heat source and the air may be supplied not only at the lower end of the recycle housing 50 but also at the side or upper end thereof. For efficient heating reaction, it is preferable that the heat source is supplied from the upper end of the recycle housing 50 in which the waste magnesia- will be.

The at least one air inflow pipe 20 is formed for introducing outside air into the central main tube housing 10 and the heat source inflow pipe 30 supplies the heat source to the inside of the central main tube housing 10 .

The heat source supplied into the central main-tube housing 10 may be gaseous fuel, liquid fuel, or solid fuel, but it may be desirable to be a fuel in a gaseous form to facilitate the supply to the central main-tube housing 10.

In addition, the recycling housing 50 may be provided with an air suction pipe 60 to suck various harmful exhaust gases that may occur during the recycling process of the waste magnesia-carbonaceous refractory and supply the harmful gas to an external noxious gas treatment device (not shown). In addition, when the temperature of the waste magnesia-caustic refractory rises excessively due to the inflow of air through the air inlet pipe 20, the temperature of the waste magnesia-caustic refractory is lowered by the suction force provided through the air suction pipe 60, It is possible to adjust the temperature inside the heat exchanger 50.

4, which is an enlarged view of the area C in FIG. 3, an air nozzle 31 is formed inside the central main tube housing 10 for air inlet gap formation, A plurality of heat source nozzles 41 are formed in the interior of the heat exchanger 40.

In this structure, the magnesia-carnitic refractory recycling apparatus 1 can directly convert waste magnesia-carnitic refractory (MgO-C) into a high-purity high-temperature coal by directly heating the inside of the recycle housing 50 instead of the conventional indirect heating method. It is regenerated with magnesia (MgO).

3 and 4, the air nozzle 31 inside the central main tube housing 10 corresponding to the air inflow gap and the heat source nozzle 41 of the heat source inflow pipe 30 Each introduced air and heat source flows into the recycled housing 50 in which the waste magnesia-carcass refractory exists and is directly heated.

Since the waste magnesia-caustic refractory (MgO-C) formed on the upper part of the perforated plate in the recycled housing 50 is continuously heated directly while causing its own reaction, the heat source inflow is stopped after a predetermined time after the start of heating, The temperature in the recycled housing 50 is raised to a predetermined temperature of 700 to 1500 DEG C, so that regenerated magnesia (MgO) having a purity of 80 to 99% can be obtained with a low energy consumption. And preferably set at a temperature of 1000 to 1200 ° C.

Specifically, the waste magnesia-caustic refractory material (MgO-C) is a material resistant to high temperature and does not soften at a temperature of at least 1,000 캜 and maintains its strength sufficiently, It is necessary to perform the combustion removal of the graphite (C).

In the present specification, combustion refers to a phenomenon in which graphite (C) reacts with a heat source to form a gas such as carbon monoxide or carbon dioxide, regardless of the presence or absence of a flame, not only in a state in which a normal material burns and sparks.

The combustion of graphite (C) particles and crystals can be carried out in the first step of approaching the reaction gas to the surface of the graphite (C), the adsorption of the reaction gas on the surface of the graphite (C) The second step, and the third step of releasing the product gas.

Here, the first and third steps are processes of physical change of gas movement, and the second step is a process of chemical change. In the reaction in which a plurality of such processes are performed in sequence, the reaction rate of the whole is determined to be the slowest process. The rate of chemical change is very slow at low temperature, but is very fast at high temperature.

More specifically, in the combustion reaction of graphite (C), electrons are referred to as a chemical reaction rate mechanism and the latter is referred to as an intragranular diffusion speed mechanism. The former and the latter temperature ranges are referred to as zones ) Ⅰ and zone Ⅲ. In addition, when the graphite (C) particles or crystals are aggregated graphite blocks, another rate mechanism between Zone I and Zone III is the pore diffusion mechanism (Inpore regime), and the temperature range is called zone II.

The three reaction rate-limiting mechanisms are merely generated in a balance between the consumption rate of the reaction gas due to the chemical change and the supply rate thereof. Therefore, the operation is common regardless of the kind of reaction gas.

This is because the graphite block is a porous material and there are many surfaces that can react inside the outer surface rather than the outer surface. In connection with the first to third zone classification, the graphite (C) is influenced by the temperature of the relative burning rate by various gases. However, the difference in the combustion speed corresponds to a temperature of 1000 ° C or less, and in the present invention, there is no difference in speed at at least 700 to 1500 ° C.

In other words, the burning rate of graphite (C) particles and crystals is governed by the rate of chemical change at low temperature and dominated by the diffusion rate of gas at high temperature, but the influence of temperature on the structure of gas,

The diffusion rate of the gas is only about 20% even when the temperature rises by 100 DEG C in the normal temperature range, so that the diffusion rate of the gas has a small value even at a low temperature, but does not increase much even if it becomes high.

Next, regarding reactive impurities contained in graphite (C), it is impurities which greatly increase the reactivity of graphite (C) crystals.

Almost all elements contained increase in reactivity whether they are large or small. The effect of the impurities is due to the catalytic action, and the reaction of the graphite (C) with the heat source may be considered to be carried out by coexistence of all the impurities.

The catalytic effect also depends on the chemical form of the impurity or the state of dispersion in the crystal. This makes it difficult to compare the catalytic capacity between the elements, but Alkali metals and transition metals are known to have particularly high catalytic capabilities.

On the other hand, an extremely limited number of elements, B, Si, P, or these compounds suppress the burning rate.

When the concentration of the specific impurity element in the graphite (C) crystal is increased, the reactivity increases in proportion to the concentration while the catalytic effect per unit concentration is gradually decreased. Characteristic of the effect of the catalyst concentration is the change in the activation energy of the reaction in Zone I or Zone II with concentration. Typically, a chemical reaction corresponds to one activation energy for one reaction.

However, in the reaction between graphite (C) and a heat source, activation energy of various reactions can be obtained when the catalyst concentration is different even when the reaction by the same kind of catalyst proceeds. This phenomenon is called a compensation effect

The following [Table 1] and [Table 2] are the ignition temperatures in the case where various impurity elements are added to the graphite (C) powder. The ignition temperature is a property which can be changed according to the measurement condition, but the measurement result under the same condition can be used for the comparison of the reactivity. This reaction is easily ignited because the graphite (C) is made into a fine powder and heated in an oxygen stream. Therefore, when the graphite (C) block is heated in the atmosphere, the block can not be ignited at temperatures as shown in [Table 1] and [Table 2].

Except for the addition of 50% of Zn, the added 21 kinds of elements have an extremely small amount of ignition temperature, and nothing is raised.

The most influential element in this experiment is Pb, not a transition metal element such as Fe or Co. In the case of this Pb element, by the addition of 0.15%, the ignition temperature dropped from 740 ° C to 382 ° C to 358 ° C. On the other hand, almost no change was observed when Sn was added in an amount of 0.1%, which was less than 2 ° C lower than that of no addition. If the addition amount of Sn is further increased, it is apparent that the effect of increasing the ignition temperature is also reversed.

Additive element Addition amount (% by weight) Ignition temperature (℃) Pb 0.15 382 V 0.20 490 Mn 0.45 523 Co 0.33 525 Cr 0.85 540 Cu 0.20 570 Mo 0.15 572 Ag 0.16 585 CD 0.21 590 Fe 0.13 593 Pt 0.03 602 Ni 0.45 613 Ir 0.40 638 Rh 0.20 622 Ru 0.30 640 Pd 0.30 659 Ce 0.72 692 Zn 50.00 700 W 0.02 718

Additive element Addition amount (% by weight) Ignition temperature (℃) Hg 0.10 720 Sn 0.10 738 No additives 740

6 is a flow chart illustrating a method for recycling a magnesia-carbonaceous refractory according to an embodiment of the present invention. 1 to 6, external air is supplied from at least one air inflow pipe 20 or external air is supplied to the central main tube housing 20 through the air inflow pipe 20 by a suction force provided from the air suction pipe 60. [ (10), and the heat source is introduced into the central main tube housing (10) through the heat source inlet pipe (30) (S11).

For this purpose, the central main-tube housing 10 is a tubular housing vertically placed in a cylindrical shape, at least one air inlet tube 20 formed at a side symmetrical with respect to a horizontal plane, And an air suction pipe 60 formed at the upper end thereof. The central main-tube housing 10 includes a heat source inlet pipe (not shown) formed at a predetermined interval of 80 to 110 degrees through the outer peripheral surface of the central main-tube housing 10 between at least one air inlet pipe 20 30).

When the air is introduced from the air inlet pipe 20, the temperature of the waste refractory material inside the recycle housing 50 may excessively increase. Therefore, the inflow of air through the air inlet pipe 20 is stopped, To control the temperature of the waste magnesia-caustic refractory in the recycle housing (50).

After the step S11, the air and the heat source introduced into the recycle housing 50 in the step S11 are introduced into the recycle housing 50 in which the waste magnesia-carbonaceous refractory is present (S12).

To this end, the central main tube housing 10 includes a plurality of heat source supply tubes 40 and an air nozzle 31 therein. The plurality of heat source supply pipes 40 are connected to the heat source inlet pipe 30 so that a heat source is introduced into the recycle housing 50. The air nozzle 31 is connected to the air inlet And is formed on the inner circumferential surface of the tube of the central main tube housing 10 corresponding to the gap. Each of the heat source supply tubes 40 forms a plurality of heat source nozzles 41 therein.

After step S12, a heating device (not shown) formed in the recycling housing 50 performs direct heating for a preset time in the recycling housing 50 (S13).

After the direct heating, the inflow of the heat source is stopped and the inflow of air is continued (S14) by controlling the opening and closing of the air inflow pipe 20, the air suction pipe 60 and the heat source inflow pipe 30 after step S13.

After the step S14, self-reaction is caused by the waste magnesia-caustic refractory (MgO-C) formed on the upper part of the perforated plate in the recycled housing 50 to rise above a predetermined temperature to obtain regenerated magnesia (S15). Here, the preset temperature corresponds to an experimental range of 700 to 1500 ° C.

As described above, preferred embodiments of the present invention have been disclosed in the present specification and drawings, and although specific terms have been used, they have been used only in a general sense to easily describe the technical contents of the present invention and to facilitate understanding of the invention , And are not intended to limit the scope of the present invention. It is to be understood by those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

10: Central main - tube housing
20: air inlet pipe
30: Heat source inlet pipe
40: Heat source supply pipe
31: air nozzle
41: heat source nozzle
50: Recycling housing
60: air suction pipe

Claims (8)

A central main-tube housing 10 for supplying a heat source and air and an air suction pipe 60 for sucking in air and a recycling housing (not shown) in which a waste magnesia-carbonaceous refractory (MgO-C) 50), and the central main-tube housing (10)
At least one air inlet pipe (20) formed for introducing outside air into the recycling housing (50) through the interior of the central main tube housing (10); And
A heat source inlet pipe (30) formed to introduce a heat source into the recycle housing (50) through the interior of the central main tube housing (10); / RTI >
And recycled magnesia (MgO) is obtained by directly heating the air and the heat source introduced into the recycled housing 50 in which the waste magnesia-kaonite refractory is present for a predetermined time
Magnesia - Carbonaceous refractory recycling device.
The method according to claim 1,
After the direct heating,
(MgO-C) formed on the upper part of the perforated plate in the recycle housing 50 according to the method of stopping the inflow of the heat source and continuously introducing air,
To obtain regenerated magnesia (MgO).
Magnesia - Carbonaceous refractory recycling device.
The method of claim 2,
The predetermined temperature may be, for example,
700 to 1500 ° C, and the obtained regenerated magnesia (MgO) has a purity of 80 to 99%
Magnesia - Carbonaceous refractory recycling device.
The method according to claim 1,
The central main-tube housing (10)
A plurality of heat source supply pipes (40) connected to the heat source inlet pipe (30) to allow a heat source to flow into the recycle housing (50); And
An air nozzle (31) for allowing air to flow into the recycling housing (50); Characterized in that
Magnesia - Carbonaceous refractory recycling device.
The method according to claim 1,
The central main-tube housing (10)
And at least one air inflow pipe (20) formed at a position symmetrical with respect to a horizontal plane on a side surface thereof, the tubular housing being vertically placed in a cylindrical shape,
And a heat source inflow pipe (30) formed between at least one air inflow pipe (20) and at a predetermined angle interval through an outer circumferential surface of the central main tube housing (10)
Magnesia - Carbonaceous refractory recycling device.
External air is supplied from at least one air inflow pipe 20 or the suction force provided from the air suction pipe 60 flows into the central main tube housing 10 through the air inflow pipe 20, A first step in which the heat source is introduced into the central main tube housing 10 through the inlet pipe 30;
A second step in which the introduced air and the heat source are introduced into the recycled housing 50 in which the waste magnesia-carbonaceous refractory is present;
And a third step of performing direct heating in the recycling housing (50) for a predetermined time period
Magnesia - Carbonaceous refractory recycling method.
The method of claim 6,
After the third step,
A fourth step of interrupting the inflow of the heat source through the open / close control of the air inflow pipe 20 and the heat source inflow pipe 30,
A fifth step of recovering magnesia (MgO) by raising the temperature of the recycled housing 50 to a predetermined temperature or higher due to self-reaction by waste magnesia-caustic refractory (MgO-C) formed on the upper part of the perforated plate; ≪ RTI ID = 0.0 >
Magnesia - Carbonaceous refractory recycling method.
The method of claim 6,
The predetermined temperature of the fifth step may be,
700 to 1500 ° C.
Magnesia - Carbonaceous refractory recycling method.

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