KR100328500B1 - Apparatus for the continuous removal of fine dust in dust-clarifying water produced from iron-making - Google Patents

Abstract

PURPOSE: An apparatus for continuous removal of fine dust in dust-clarifying water produced from iron-making using magnetic field is provided. CONSTITUTION: The apparatus comprises a tank(100) for storing and supplying iron manufacturing dust removing water (SW); first magnetic fluid separation tower(200) for collecting magnetic dust (MFF) only contained in the iron manufacturing dust removing water (SW) from upflow by receiving the iron manufacturing dust removing water (SW) and discharging first magnetic fluid separation water (W1); a dust removing water supply part(110) for supplying the iron manufacturing dust removing water (SW) into the first magnetic fluid separation tower(200); first discharge part(210) for discharging magnetic dust (MFF) generated from the first magnetic fluid separation tower(200); a magnetic dust recovery machine(600) for dehydrating and collecting the magnetic dust (MFF) to recover the magnetic dust (MFF) discharged from the first discharge part(210); a magnetic fine powder manufacturing machine(800) for manufacturing the magnetic dust (MFF) into magnetic fine powder, a hopper(300) for storing and supplying magnetic fine powder (MF) supplied to first magnetic fluid separation water (W1); a slurry agitation mixing tank(400) for preparing a mixed slurry by agitating and mixing the magnetic fine powder (MF); second magnetic fluid separation tower(500) for collecting magnetic floc (MS) only from upflow and discharging second magnetic fluid separation water (W2); second discharge part(510) for discharging the magnetic floc (MS) and water; and a fluidized bed magnetic fine powder recovering machine(700) for supplying the magnetic fine powder (MF) to the hopper(300) by separating the magnetic fine powder (MF) only from the magnetic floc (MS).

Description

Magnetic fluid separation device for continuous removal of dust in seasonal dedusting {APPARATUS FOR THE CONTINUOUS REMOVAL OF FINE DUST IN DUST-CLARIFYING WATER PRODUCED FROM IRON-MAKING}

The present invention relates to a continuous removal device of dust in steelmaking, more specifically, to quickly and efficiently remove dust in dust generated during the wet removal process of the dust in the metallurgical and refining process of the steelmaking industry. The present invention relates to a continuous removal device of dust in steelmaking to remove water to prevent water pollution or to recover water and reuse it in the steelmaking process.

Generally, iron ore, coke, limestone, etc. are put into the furnace and blown preheated air from the lower part of the furnace to melt and decompose iron ore. Cooling water and cleaning gas generated from the blast furnace are used, and since both are indirect cooling, almost no water is contaminated. Therefore, they are discharged or cooled without re-purification and reused. It contains a lot of dust from iron ore, coke and limestone, so it must be discharged after purification.

In addition, in the steelmaking process where scrap and solvent are added to the pig iron produced in the steelmaking process and heated and melted in a converter to remove carbon, oxygen, and other impurities, the steelmaking process is discharged or cooled and reused as in the steelmaking process. Gas cleaners must be dusted and discharged or reused.

The concentration of dust in the furnace dust removal is about 500-3,000 mg / l (; ppm) and the concentration of dust in the converter gas cleaning waste water is 2,000-5,000 mg / l (; ppm). There are relatively large particles, and if it is left standing for 2 ~ 3 hours, dust of over 100㎛, which is equivalent to about 80%, is sedimented and removed.However, in order to achieve 50 ~ 100 mg / l (; ppm), a dust concentration suitable for discharge or reused water Coagulation sedimentation method is applied.

As the flocculant used in the flocculation sedimentation method, aluminum sulfate is mainly used, and the sludge of the flocculated dust is increased to about 100 to 400 g / l in the sedimentation basin. In this case, convection occurs in the settling tank, which impedes the sedimentation of the settling particles, and the treated water becomes turbid. Therefore, a strong coagulant such as a polymer flocculant must be used, and at the same time Ca (OH) 2 or Further injection of Na 2 CO 3 not only increases treatment costs but also limits the use of treated water due to the remaining flocculant in the treated water.

Applicant noticed in Korean Patent Laid-Open Publication No. 97-74666 that cohesive force such as van der Waals force is formed between suspended solids and magnetic fine powder in agricultural and livestock raising and household waste paper to form floccule. By mixing and stirring the magnetic fine powder to form a magnetic floc with suspended solids adsorbed, and floating the magnetic floc in a magnetic fluid separation method by separating and discharging the magnetic floc in a radial magnetic force stronger than gravity or fluid force during the flow of the fluid A method of removing solids has been proposed.

That is, as shown in FIG. 1, when the suspended solids S in the dustbinding meet the magnetic fine powder MF, the suspended solids S are adsorbed on the magnetic fine powder MF to form the magnetic flocs MF. When the magnetic flocs MF pass through the magnetic fluid separation tower 50, the magnetic flocs MF are adsorbed to the magnetic set 8 installed at the outer circumference of the magnetic fluid separation tower 50 to continuously separate and discharge the magnetic flocs MF. The magnetic powder (MF) from which the suspended solids (S) are separated through the drying or combustion process of) is recovered and reused for dust removal purification.

Magnetic powder used for the operation of magnetic fluid separation in which the removal efficiency is very high when the method described in Korean Patent Laid-Open Publication No. 97-74666 is applied to the steelmaking dedusting, but the magnetic powder should be mixed at an appropriate ratio in dust concentration. The amount of the magnetic flux sludge increases in proportion to the amount of and thus the problem that the treatment cost due to their dehydration, drying, etc. also increases.

The present invention is to solve the above problems, as shown in Table 1 in the dust in the steelmaking dusting magnetic powder to focus on the magnetic iron containing FeO or metal Fe component containing up to 70 ~ 85% I didn't commit at all

(Table 1) Representative components (wt%) of dust in steelmaking

After removing about 60 to 80% of the dust in the original steelmaking dust by passing the original steelmaking dust treatment to a magnetic fluid separation tower, The magnetic fine powder is mixed and stirred at an appropriate ratio so that the dust remaining in the primary magnetic fluid is adsorbed to the magnetic fine powder to form a magnetic floc, and then the primary magnetic fluid is passed through the secondary magnetic fluid separation tower. By removing 90-95% or more of the dust in steelmaking dusting to re-use the steelmaking dusting, and also to recover the entire amount of magnetic dust obtained from the primary magnetic fluid separation tower of the original steelmaking It is an object of the present invention to provide an apparatus which can be used as a raw material for manufacturing iron-based magnetic fine powder proposed in Patent Application No. 98-26528. In the magnetic fluid separation tower that is equipped with a plurality of magnets in the direction to remove the magnetic plug by the on and off of the magnetic force, the tank for storing and supplying the original steel dedusting and the original steel damping A primary magnetic fluid separation tower which collects only the magnetic dust contained in the original steelmaking dedusting stream and discharges the first magnetic fluid separation water, and a dusting supply unit which supplies the original steelmaking dedusting to the primary magnetic fluid separation tower; And a first discharge part for discharging the magnetic dust generated from the primary magnetic fluid separation tower, a magnetic dust recovery unit for dewatering and collecting the magnetic dust discharged from the first discharge unit, and collected in the magnetic dust recovery unit. Magnetic powder manufacturing machine that manufactures the magnetic powder into the magnetic powder, and the magnetic powder is supplied to the primary magnetic fluid separation water passing through the primary magnetic fluid separation tower A hopper for storing and supplying fine powder, a slurry stirring mixing tank for stirring and mixing the primary magnetic fluid separation water and the magnetic fine powder supplied from the hopper to produce a mixed slurry, and a magnetic flop produced in the slurry stirring mixing tank; A slurry supply unit for discharging the mixed slurry composed of water, a secondary magnetic fluid separation tower for receiving the slurry supplied from the slurry supply unit, collecting the magnetic flux from an upstream stream, and discharging the secondary magnetic fluid separation water, and the secondary A fluidized bed magnetic fine powder recovery device that separates only the magnetic fine powder from the magnetic flux discharged from the magnetic fluid separation tower and the second discharge portion for discharging water, and the magnetic flux discharged from the secondary magnetic fluid separation tower and supplies it to the hopper. It is characterized by consisting of.

1 is a conceptual diagram of the formation and magnetic separation of magnetic flocs according to the present invention.

Figure 2 is a block diagram of a magnetic fluid separation device for the continuous removal of dust in steelmaking dust according to the present invention.

Figure 3 is a block diagram of a magnetic fluid separation device for the continuous removal of dust in the steelmaking dusting of the present invention.

Figure 4 is an effect of the ball tower flow rate of the original steel milling dust on the removal efficiency of the dust when passing the mixed dusting of the steelmaking and steelmaking process to the primary magnetic fluid separation tower in the apparatus according to the present invention

5 is the first magnetic fluid separation water and the magnetic powder for the final removal efficiency of the dust when the first magnetic fluid separation water and the magnetic powder (MF) mixing slurry in the apparatus according to the present invention passed through the secondary magnetic fluid separation tower Effect of Ball Tower Flow Rate of Mixed Slurry

<Description of the symbols for the main parts of the drawings>

100 tank 200 primary magnetic fluid separation tower

300: hopper 400: slurry stirring mixing tank

500: secondary magnetic fluid separation tower 600: magnetic dust recovery

700: magnetic fine powder recovery machine 800: magnetic fine powder production machine

MF: magnetic fine powder S: suspended solid

MS: Magnetic Flux MFF: Magnetic Dust

SW: Original steel milling W1: Primary magnetic fluid separation water

W2: Secondary magnetic fluid separation water W: Water

Hereinafter, described in detail by the accompanying drawings as follows.

2 is a block diagram of an apparatus for continuous removal of dust in steelmaking dust according to the present invention, Figure 3 is a block diagram of a magnetic fluid separation device for the continuous removal of dust in the steelmaking dusting of the present invention, The tank 100 for storing and supplying the dedusting SW, and the magnetic dust (MFF) contained in the original dedusting SW is collected from the upstream flow by receiving the raw seasonal dedusting SW. And a primary magnetic fluid separation tower 200 for discharging the primary magnetic fluid separation water W1 and a dust removal supply unit 110 for supplying the original steelmaking dedusting SW to the primary magnetic fluid separation tower 200. And, the first discharge portion 210 for discharging the magnetic dust (MFF) generated from the primary magnetic fluid separation tower 200, and the magnetic dust discharged from the first discharge portion (210) ( Magnetic dust recovery unit 600 for collecting dehydration to recover MFF), and the magnetic dust recovery unit 600 A magnetic powder manufacturing apparatus 800 for preparing the collected magnetic dust (MFF) as magnetic fine powder is provided. In addition, the magnetic powder is supplied to the primary magnetic fluid separation water W1 passed through the primary magnetic fluid separation tower 200. Slurry for mixing and mixing the hopper 300 for storage and supply of the magnetic fine powder (MF) and the magnetic fine powder (MF) supplied from the primary magnetic fluid separation water (W1) and the hopper 300 to form a mixed slurry (slurry) from the slurry supply unit (41) for discharging a mixed slurry composed of a stirring mixing tank (400), magnetic flux (MS) generated in the slurry stirring mixing tank (400) and water, and the slurry supply unit (41) Secondary magnetic fluid separation tower 500 for collecting only the magnetic flux (MS) from the upstream flow and the discharge of the second purified magnetic fluid separation water (W2) receiving the supplied slurry, and the secondary magnetic fluid separation tower Discharge magnetic flux (MS) and water from 500 Fluidized bed magnetic fine powder recovery unit for separating only the magnetic fine powder (MF) from the second discharge unit 510 and the magnetic flux (MS) discharged from the secondary magnetic fluid separation tower 500 and supplying it to the hopper 300 The first and second discharge parts 210 and 510 may include the second and fourth valves V2 and V4 for controlling the flow of the magnetic powder MFF and the magnetic flop MS. And a dehydrator 11 and 12 for removing water. In addition, the dust removal supply unit 110 and the slurry supply unit 410 may include a pump for forcibly supplying a vibration suppression or primary magnetic fluid separation water W1 ( 9) 10 and the first and third valves V1 and V3 for controlling flow. The primary and secondary magnetic fluid separation towers 200 and 500 are hollow in the middle. In addition, a plurality of magnets 8 are provided on the outer circumference of the outer wall 7 of the primary and secondary magnetic fluid separation towers 200 and 500.

The process of purifying steelmaking dust by the magnetic fluid separation device for continuous removal of dust in the steelmaking dusting made as described above will be described in detail with reference to the device configuration of FIG. 3. The inflow rate of raw iron dedusting (SW) varies depending on the operating conditions of the steelmaking and steelmaking process, and the inflow rate of raw iron dedusting (SW) and the concentration of dust are different. Minimize concentration variations.

Thereafter, the original steelmaking dedusting SW controlled in the tank 100 may be controlled by the dedusting pump 9 of the dedusting supply unit 110 and the first valve V1 of the primary magnetic fluid separation tower 200. It flows into the lower one side, wherein the air column flow rate of the original steelmaking dehumidification (SW) in the primary magnetic fluid separation tower 200 acts on the dust in consideration of the correlation between the magnetic force, the fluid force and the sedimentation force of the dust The magnetic force is controlled to be relatively stronger than the fluid force and the sedimentation force.

On the other hand, the magnetic dust (MFF) contained in the original steel dedusting (SW) is passed through the primary magnetic fluid separation tower 200, a plurality of magnet sets mounted in multiple stages on the outer wall (7) of the primary magnetic fluid separation tower Attached to (8) and removed, the first magnetic fluid separation water (W1) from which the magnetic dust (MFF) is removed is continuously discharged to the upper side of the first magnetic fluid separation tower 200, slurry stirring mixing tank (400) The wet or dry magnetic fine powder (MF) stored in the hopper 300 is supplied to the primary magnetic fluid separation water (W1) and the stirrer (1) continuously introduced into the slurry stirring mixing tank (400). At this time, the magnetic fine powder (MF) adsorbs the magnetic dust (MFF) remaining in the primary magnetic fluid separation water (W1) to form a magnetic flux (MS), and in the slurry stirring mixing tank 400 Binary dust and magnetic flocs (MS) form a mixed slurry.

Here, the input ratio of the magnetic fine powder MF supplied to the primary magnetic fluid separation water W1 passing through the primary magnetic fluid separation tower 200 is 1 based on the concentration of dust in the primary magnetic fluid separation water W1. Mix in the range of 1: 1 to 1: 4.

The mixed slurry prepared as described above is introduced into the lower one side of the secondary magnetic fluid separation tower 500 by the slurry pump 10 and the third valve V3 of the slurry supply unit 410. As in (200), the turret flow velocity of the mixed slurry is relatively stronger than the fluid force and the sedimentation force in consideration of the correlation between the magnetic force and the fluid force and the sedimentation force of the magnetic flocs. Control it to work.

Therefore, as in the first magnetic fluid separation tower 200, the magnetic flux MS is removed by the magnet set 8 mounted in multiple stages on the outer wall 7 of the second magnetic fluid separation tower 500. Secondary magnetic fluid separation water (W2) is discharged to the upper one side of the secondary magnetic fluid separation tower 500 is purified to the stage that can be reused. Magnetic dust (MFF) collected in the primary magnetic fluid separation tower 200 When the load is increased, the first valve V1 of the dust removal supply unit 110 is closed to stop the supply of the original steelmaking dehumidification SW for several minutes, and the magnetic force of the magnet set 8 is turned off. Opening the second valve (V2) of the first discharge portion 210 installed below the secondary magnetic fluid separation tower 200 to discharge the magnetic dust (MFF) with the water in the primary magnetic fluid separation tower 200, The magnetic dust (MFF) is recovered from the dehydrator 11 to recover the magnetic dust (MFF) from the magnetic dust recovery device 600. The magnetic dust (MFF) thus recovered is made of magnetic fine powder. It is transferred to the early stage 800 to be used as a raw material for the production of magnetic fine powder (MF). At the same time, when the load of the magnetic flux (MS) collected in the secondary magnetic fluid separation tower 500 increases, the primary magnetic fluid separation is performed. In the same manner as in the tower 200, the third valve V3 of the slurry supply unit 410 is closed to stop the supply of the mixed slurry for several minutes, and the magnetic force of the magnet set 8 is turned off. The fourth valve V4 of the second outlet 510 installed below the fluid separation tower 500 is opened to discharge the magnetic flocs MS together with the water in the secondary magnetic fluid separation tower 500, and a dehydrator ( Dehydration in 12) to transfer the magnetic flux (MS) to the magnetic fine powder recovery 700. In the magnetic fine powder recovery (700) to remove the suspended solids (S) in the magnetic flux (MS) by the magnetic fine powder (MF) ), And the magnetic fine powder (MF) is supplied to the hopper 300, the primary magnetic fluid in the slurry stirring mixing tank 400 It is used to make magnetic flux (MS) by adsorbing with magnetic powder remaining (MFF) remaining in the separation water (W1). Then, in the primary magnetic fluid separation tower 200 and the secondary magnetic fluid separation tower 500, When the recovery of the magnetic dust (MFF) and the magnetic flux (MS) is completed, the second and fourth valves (V2) and (V4) are closed to prevent the original steel dedusting (SW) and the mixed slurry flowing into the magnetic fluid separation tower. After the magnetic force of the magnet set 8 mounted on the outer walls of the primary and secondary magnetic fluid separation towers 200 and 500 is turned on, the magnetic dust (MFF) and magnetic flux (MS) The first and third valves V1 and V3 which were closed during the recovery process were opened to supply the original steelmaking dedusting SW and the mixed slurry to the primary and secondary magnetic fluid separation towers 200 and 500, respectively. In this apparatus, the concentration of dust in the original steel dedusting (SW), the primary and secondary magnetic fluid separation towers (2) of the original steel dedusting (SW) and the primary magnetic fluid separation water (W1) 00) (500) ball tower flow rate, mass ratio of magnetic fine powder (MF) to dust in primary magnetic fluid separation water (W1), type of magnetic fine powder (MF), magnetic force and arrangement of magnet in magnet set (8) And according to the singular can remove the dust removal efficiency.

By measuring the removal efficiency of dust in steelmaking dehumidification by such a device as follows.

Figure 4 is the original steel milling dust (SW) for the removal efficiency of dust when passed through the primary magnetic fluid separation tower 200 of the mixed steelmaking process of the steelmaking and steelmaking process with the original steel milling dust (SW) in the apparatus of the present invention It is shown that the relationship with the tower flow velocity of the dust is removed in the range of about 60 ~ 80% in the tower dedusting flow rate range of about 0.2 ~ 0.85cm / s.

FIG. 5 shows the primary magnetic properties of the final removal efficiency of dust when the mixed slurry of the primary magnetic fluid separation water (W1) and the magnetic fine powder (MF) is passed through the secondary magnetic fluid separation tower 500 in the apparatus of the present invention. The relationship between the ball column flow rate of the fluid separation water (W1) and the magnetic fine powder (MF) mixture slurry is shown. The magnetic fine powder (MF) for forming dust and magnetic flux (MS) in the primary magnetic fluid separation water (W1) is shown. ) Used magnetite, steel sludge and magnetite. It can be seen that dust is removed within the range of about 75-99% based on the concentration of dust in the original steel-making dedusting (SW) in the range of about 0.2 ~ 0.85cm / s of tower dedusting flow rate.

In the present apparatus, the magnetic force of the magnet set 8 is strengthened to increase the magnetic force acting on the collection of the magnetic flocs MS in the secondary magnetic fluid separation tower 500, thereby increasing the ballast dusting flow rate, that is, increasing the fluid force. The removal efficiency of dust, which is reduced by, was found to be significantly reduced.

As described above, in the present invention, magnetic powder (MF) is not added at all, in view of the fact that the iron in the dust-making dust contains up to 70 to 85% of the FeO or metal Fe component. After removing about 60 to 80% of the dust in the original steel dedusting (SW) by passing the raw steel dedusting (SW) to the primary magnetic fluid separation tower 200, that is, Based on the concentration of the dust in the magnetic fluid separation water (W1), the magnetic fine powder (MF) is mixed and stirred in a ratio of 1: 1-1: 4, so that the dust remaining in the primary magnetic fluid separation water (W1) is magnetic fine powder ( After adsorbing to the MF to form the magnetic flux MS, the mixed slurry composed of the magnetic flux MS and the water in the primary magnetic fluid separation water W1 is passed through the secondary magnetic fluid separation tower 500 to produce steel. Purification of dust to be reused in the process by removing more than 90-95% of dust in dusting By reducing the amount of magnetic powder (MF) by 60 to 80% than proposed in the Republic of Korea Patent Publication No. 97-74666, and also in the primary magnetic fluid separation tower 200 of the original steelmaking (SW) The obtained magnetic dust (MFF) can be collected as a raw material of the steel-based magnetic fine powder (MF) proposed in Korean Patent Application No. 98-26528.

Claims (3)

In the case of using a magnetic fluid separation tower in which a plurality of magnets are mounted in the circumferential direction of the outer wall of the exterior to remove the magnetic flops by turning the magnetic force on and off, Tank 100 for the storage and supply of the original steel dedusting (SW), The primary magnetic fluid separation tower that receives the raw steel dedusting (SW) and collects only the magnetic dust (MFF) contained in the original steel dedusting (SW) from the upstream flow and discharges the primary magnetic fluid separation water (W1). 200, And a dedusting supply unit 110 for supplying the original steel dedusting (SW) to the primary magnetic fluid separation tower 200, A first discharge part 210 for discharging the magnetic dust (MFF) generated from the primary magnetic fluid separation tower 200; A magnetic dust recoverer 600 which collects and dehydrates to recover the magnetic dust (MFF) discharged from the first discharge part 210; A magnetic powder maker 800 for manufacturing magnetic powder (MFF) collected in the magnetic dust collector 600 using magnetic powder, and A hopper 300 for storing and supplying the magnetic fine powder MF supplied to the primary magnetic fluid separation water W1 passing through the primary magnetic fluid separation tower 200; A slurry stirring mixing tank 400 for stirring and mixing the first magnetic fluid separation water W1 and the magnetic fine powder MF supplied from the hopper 300 to form a mixing slurry, Slurry supply unit 41 for discharging the mixed slurry consisting of magnetic flux (MS) and water generated in the slurry stirring mixing tank 400, A secondary magnetic fluid separation tower 500 which receives only the slurry supplied from the slurry supply part 41 and collects only the magnetic flux MS from the upstream flow and discharges the secondary magnetic fluid separation water W2; A second discharge part 510 for discharging the magnetic flux MS and water discharged from the secondary magnetic fluid separation tower 500; Characterized in that it consists of a fluidized bed magnetic powder recovery unit 700 that separates only the magnetic powder (MF) from the magnetic flux (MS) discharged from the secondary magnetic fluid separation tower 500 and supplies it to the hopper 300 Magnetic fluid separation device for continuous removal of dust in steelmaking. According to claim 1, wherein the input ratio of the magnetic fine powder (MF) supplied to the primary magnetic fluid separation water (W1) passing through the primary magnetic fluid separation tower 200, Continuous removal apparatus of dust in steelmaking dust, characterized in that the mixture in the range of 1: 1 to 1: 4 based on the concentration of the dust in the primary magnetic fluid separation water (W1). According to claim 1 or 2, the magnetic fine powder (MF) supplied to the primary magnetic fluid separation water (W1) passing through the primary magnetic fluid separation tower 200, In addition to reagent magnetite, magnetic iron ore of fine powder used in the sintering process of iron making in ironworks, magnetic iron powder from reduction of hematite, steelmaking sludge discharged from the steelmaking process, and iron-based magnetic fine powder obtained by pulverizing dust of electric furnace Apparatus for continuous removal of dust in steelmaking dedusting, characterized by using (MF).