JPH0666477A - Device for recovering quick lime powder produced on sintered ore - Google Patents

Abstract

(57) [Abstract] [Purpose] Quick lime powder generated on the upper surface of sinter ore on the pallet of a sinter machine is recovered at a high recovery rate without contacting the sinter ore with a recovery device. [Structure] A scraper for scraping quicklime powder, a suction nozzle for sucking the quicklime powder scraped up, a pre-stage collecting means having a hood for preventing the quicklime powder from scattering, or a suction nozzle for sucking quicklime powder, A pre-stage collecting means having a hood for preventing the escape, an air blow nozzle for scattering the residual quick lime powder, a suction nozzle for sucking the scattered quick lime powder, and a post-stage collecting means having a hood for preventing the quick lime powder from scattering. Both of them are arranged such that at least their lower ends are located above the apex of the upper surface of the sintered ore.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention provides a mixture of coke powder and limestone powder on the upper surface of a raw material mixture on a pallet of a sintering machine, which is fired by an igniter to obtain quicklime powder. The present invention relates to a device for recovering the obtained quicklime powder from the sinter ore on the downstream side of the ignition device in the pallet moving direction.

[0002]

2. Description of the Related Art A schematic diagram of a sintering operation is shown in FIG. The mixed raw material 2 cut out from the feed hopper 4 is stacked and supplied on the bedding ore cut out from the bedding hopper 3 onto the pallet 1. The blended raw material 2 is ignited by the ignition device 15 and blower 14
The powdered coke in the blended raw material is burned by the suction air of, and the blended raw material 2 is sintered to be a sinter. The sinter is crushed by the crusher 5, cooled by the cooler 6, and then classified by the sieve 7. Sintered ore having a particle size of 8 to 16 mm on the sieve is returned to the bedding hopper 3 as a bedding ore 10, and particles having a particle size of 5 mm or less are mixed with the new raw material 12 by the mixer 8 as a return ore 11 and then supplied. Returned to the ore hopper 4. The residue is transferred to the blast furnace as a sintered ore product 13.

Generally, as a means for improving the air permeability of the blended raw material 2 on the pallet 1, a binder may be mixed into the blended raw material 2. As a binder, normal quick lime (Ca
O) is often used. As a method for inexpensively producing and utilizing this quicklime, Japanese Patent Laid-Open No. 58-133331 discloses a limestone (CaCO ₃ ) powder 9 cut out by a limestone hopper 16 and laminated on the surface of a raw material mixture 2 to ignite the device 1.
A method has been proposed in which limestone powder is made into quick lime powder (CaO) by No. 5 and is recovered together with returned ore 11 by a sieve 7 and used as a binder.

However, according to this method, (1) the sinter ore product 13 and the return ore 11 are not completely separated by the sieve 7, and quicklime powder is mixed into the product 13. (2) A part of the quicklime powder produced by the air-cooling by the cooler 6 is scattered. There is a problem such as.

Therefore, in Japanese Patent Laid-Open No. 1-147023, in order to improve the recovery yield of quicklime powder as compared with the classification method by sieving, the quicklime powder produced is scraped with a scraper.
A method of sucking and collecting on a pallet by a blower or the like has been proposed. However, in this method, the quicklime powder mechanically scraped by the scraper is sucked by the blower, so that the sintering raw material particle size and the non-uniform distribution of the compounding components in the traveling direction and the width direction of the pallet of the sintering machine may be different. There are the following problems due to the unevenness of the upper surface of the sintered ore feeding on the pallet. (1) Quicklime powder that has entered the recesses on the surface of the sinter is left behind. (2) The recovery device is caught on the convex portion of the surface of the sinter, and the recovery device is inclined or damaged.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus capable of recovering quicklime powder from a pallet while preventing tilting and damage of the quicklime powder leaving and recovery apparatus. And

[0007]

According to the present invention, in order to solve the above problems, the lower end of the means for collecting quicklime powder is disposed at least above the apex of the convex portion of the sintered ore. On a pallet of a binding machine, an apparatus for charging a mixture of coke powder and limestone powder on the upper surface of the raw material and sintering it, and collecting the produced quicklime powder from the pallet, the pallet from an ignition device that ignites the raw material Downstream of the moving direction of
A scraper that scrapes the quicklime powder generated on the sinter,
A suction nozzle for sucking the quicklime powder scraped up, a scraper and a pre-stage collecting means having a hood provided around the suction nozzle to prevent the quicklime powder from scattering, or a suction nozzle for sucking the quicklime powder, a suction nozzle. A pre-stage recovery means having a hood that is provided around the lime to prevent the dispersion of quicklime powder, an air blow nozzle that scatters the quicklime powder remaining on the sinter, a suction nozzle that sucks the scattered quicklime powder, and an air blow nozzle. And a rear-stage recovery means having a hood provided around the suction nozzle to prevent the quicklime powder from escaping, and the lower ends of the recovery means are positioned at least above the apex of the convex portion of the sintered ore, and are sequentially arranged. It is a device for collecting quicklime powder produced on a sinter, which is characterized by being installed.

[0008]

[Function] Generally, the unevenness of the top surface of the sinter is not only the non-uniform charging of the raw materials on the pallet, but also the deposits generated on the leveling plate used to smooth the top surface before ignition. It is also caused by scratches on the upper surface of the raw material due to the above and nonuniformity of the grate gap of the pallet, and irregularities of about 10 to 30 mm are usually generated at the position where the quicklime powder after ignition and firing is collected.

According to the present invention, most of the produced quicklime powder is collected by the pre-stage recovery means, the scraper and the suction nozzle,
Alternatively, the suction nozzle can collect the quicklime powder while preventing it from being scattered by the hood, and the pre-stage recovery means is arranged such that the lower end thereof is located at least above the apex of the convex portion of the sintered ore. Therefore, there is no problem due to contact with the apex.

Since the former-stage collecting means is disposed above the apex, a part of the quicklime powder remains on the upper surface of the sintered ore. In order to recover this residual quicklime powder, a rear-stage recovery means is provided in the present invention. In the latter-stage recovery means, quicklime powder remaining in the recesses on the upper surface of the sinter is also scattered upward by air blow, the hood prevents the dispersion, and the suction nozzle collects most of it, so the amount left behind is small. In addition, since the lower end of the latter-stage collecting means is also arranged so that the lower end thereof is located at least above the apex, no problem occurs due to contact with the apex.

The distance between the lower ends of the front and rear recovery means and the apex may be about 10 to 20 mm. Therefore, in the present invention, since the smooth operation of the device and improvement of the recovery efficiency can be obtained, the obstruction of the passage of the air by the remaining quicklime is minimized, and the amount of the binder that can be recycled can be increased. When compared, the thickness of the sintering raw material layer can be increased and the coke unit consumption can be reduced.

FIG. 1 is a vertical cross-sectional explanatory view showing an example of the structure of the device of the present invention. The front hood 21 includes a front suction nozzle 17 and a scraper 18, and the rear hood 22 includes a rear suction nozzle 19 and an air blow nozzle 20. The sucked air is supplied from the entire surface in the case of the front hood 21, and from the air blow nozzle 20 and the rear surface of the hood in the case of the rear hood 22.

The scraper 18 may not be provided if the suction force of the front suction nozzle 17 is increased. Note that the upward scattering effect of air blow works effectively when there is a hard reflecting surface below the object to be scattered (quick lime powder in this case). When there is powder, the effect of scattering upward cannot be obtained even if air blow is added.

[0014]

FIG. 2 is an explanatory view of a main part of a longitudinal section of an embodiment, and FIG.
2 is a plan view showing the arrangement of the hood, suction nozzle, air blow nozzle and seal skirt of the embodiment shown in FIG. 2, and FIG. 4 is the front hood, side seal skirt, front suction nozzle of the embodiment shown in FIG. FIG. 3 is a vertical cross-sectional explanatory view showing the arrangement of scrapers, and in the present embodiment, front and rear recovery means are connected to the front and rear.

In this embodiment, quicklime powder having a width of 1000 mm is to be collected, and the front stage suction nozzle 17 has an inner diameter of 5 mm.
Eight cylinders of 0 mm are arranged in the width direction, and the inner diameter is 200 mm.
Is connected to the suction pipe 29a. Further, nine rear-stage suction nozzles 19 are arranged in a cylinder having an inner diameter of 50 mm and are connected to a suction pipe 29b having an inner diameter of 200 mm similar to the former stage, and an inner diameter of 25 mm connected to the pressure air pipe 30 is provided around the rear-stage suction nozzle. The air blow nozzle 20 of FIG.

Further, as shown in FIGS. 3 and 4, in order to prevent atmospheric air from entering the hood and scattering of quicklime powder due to air blow, sealing skirts 27 are provided on the side surfaces of the front hood 21 and the rear hood 22. However, a rear seal skirt 28 is attached to the rear surface of the rear hood 22. On a sintering machine with a pallet speed of 2 m / min, the layer thickness is 50 mm,
After producing quicklime powder having a width of 3000 mm, three sets of devices shown in FIGS. 2, 3 and 4 are arranged in the width direction, and the wind speed in the front and rear suction pipes is 40 m / sec, and the air blow wind speed is 80 m / s.
Table 1 shows the results of recovery under the conditions of ec.

For comparison, Table 1 also shows the results of suction and recovery using only the pre-stage suction nozzle corresponding to the conventional method. Further, as an example corresponding to the case where the conventional method is simply made in multiple stages, an example in which the front and rear suction nozzles are simultaneously used is also shown in Table 1.
It was shown to. In this case, the air sucked by the rear suction nozzle was adjusted by opening a gap between the rear seal skirt 28 of FIGS.

The recovery efficiency shown in Table 1 is the ratio of the recovered weight of the object to be recovered (quicklime powder) to the weight before recovery.

[0019]

[Table 1]

In the present invention, since the air blowing is performed in the latter stage, the recovery efficiency of 20% or more is improved as compared with the conventional method or the reference method without contacting the recovery means of all the stages and the latter stage with the sinter. Obtained. Also, because the collection efficiency is improved,
Since the blending ratio of the recovered quicklime can be increased and the obstruction of aeration due to the remaining residue can be reduced, the layer thickness of the sintering raw material can be increased, and the coke unit can be reduced by 1 kg / t-sinter ore or more.

In this embodiment, the two-stage suction and recovery of the front and rear stages have been described, but the front and rear stages may be further divided into multiple stages. Further, for the air blow in the latter stage, the pressure air may be intermittently sent in a pulsed manner, and the insufficient suction air amount in that case may be sucked from the gap between the rear seal skirt and the sintered ore shown in FIGS. .

[0022]

According to the present invention, since quicklime powder scattered by air blow is collected by suction in the latter stage, it is not necessary to bring the former and latter stage collecting means close to the upper surface of the sinter.
It has become possible to prevent equipment damage due to contact between the recovery means and the sinter. Further, since the collection efficiency is improved, the obstruction of aeration due to the remaining unburned lime powder is reduced, and the mixing ratio of the quicklime to be recycled can be increased.

As a result, the layer thickness of the sintering raw material can be increased and the unit of coke can be reduced, and the cost of the sintering process can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of an example of the configuration of the present invention.

FIG. 2 is a partial vertical cross-sectional main part explanatory view of the embodiment.

FIG. 3 is a hood, a suction nozzle, of the embodiment shown in FIG.
It is a plane explanatory view showing arrangement of an air blow nozzle and a seal skirt.

4 is a cross-sectional explanatory view showing the arrangement of a front hood, a side seal skirt, a front suction nozzle, and a scraper in the embodiment shown in FIG.

FIG. 5 is an explanatory view showing an outline of a conventional sintering operation.

[Explanation of symbols]

 1 Pallet 2 Blended raw material 3 Bedding hopper 4 Feeding hopper 5 Crusher 6 Cooler 7 Sieve 8 Mixer 9 Mixture of limestone powder / coke powder 10 Bed ore 11 New raw material 13 Sintered ore product 14 Blower 15 Ignition device 16 Hopper for limestone 17 Front suction nozzle 18 Scraper 19 Rear suction nozzle 20 Air blow nozzle 21 Front hood 22 Rear hood 23, 24 Atmosphere 25 Sintered ore 26 Quick lime powder 27 Side seal skirt 28 Rear seal skirt 29a, 29b Suction tube 30 Pressure air Piping 31 Pressure control valve

Claims (1)

[Claims] 1. A device for charging a mixture of coke powder and limestone powder onto the upper surface of a raw material on a pallet of a sintering machine, sintering the mixture, and recovering the produced quicklime powder from the pallet. A scraper for scraping the quicklime powder generated on the sinter, downstream of the igniter in the moving direction of the pallet,
A suction nozzle for sucking the quicklime powder scraped up, a scraper and a pre-stage collecting means having a hood provided around the suction nozzle to prevent the quicklime powder from scattering, or a suction nozzle for sucking the quicklime powder, a suction nozzle. Front-stage collection means that has a hood that is surrounded and has a hood that prevents the dispersion of quicklime powder, an air blow nozzle that scatters the quicklime powder remaining on the sinter, a suction nozzle that sucks the scattered quicklime powder, and an air blow nozzle. And the rear-stage recovery means having a hood provided around the suction nozzle to prevent the quicklime powder from escaping, and the lower end of each recovery means is positioned at least above the apex of the convex portion of the sinter ore, and is sequentially arranged. A device for recovering quicklime powder produced on a sintered ore characterized by being installed.