JPH04236092A - Adding method of coke powder for sintering - Google Patents

Abstract

PURPOSE:To regulate the distribution of the amount of coke as well as the grain size of the coke by a method wherein a plurality of blowing nozzles for blowing the powder of coke are provided to blow and add the coke powder into a material layer charged on a pallet. CONSTITUTION:Coke powder, crushed into the grain size of 3mm or less, is screened by a sieve 3 of 1mm and the powder is divided into the powder 4 above the sieve and the powder 5 below the sieve to reserve them into tanks respectively while the powder of CDQ (coke dust generated from a coke drying and digesting device) and the like are reserved into a different reserving tank as fine powder of coke 2. On the other hand, blowing nozzles 18-20 for blowing coke powder 1 together with carrier gas are provided at positions opposed to the slope of charging accumulation 24 formed of the charging of sintering material. Respective set amounts are fed by scale conveyers 9-11 from reserving tanks 6-8 and mixed with the carrier gas, then, the powder of CDQ is added by blowing it into the upper layer of the accumulation 24. At the same time, powder 5 below the sieve is blown through blowing nozzle 19 to blow and add it to the middle layer of the accumulation 24 and the powder 4 above the sieve is blown and added to the lower layer of the accumulation 24 by the blowing nozzle 20 respectively.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of adding coke powder for sintering which allows adjustment of coke particle size and coke amount distribution in a raw material layer on a pallet.

0002

[Prior Art] Sintered ore is a coated iron ore powder with a suitable particle size.
Mix coke powder and limestone powder, supply this mixture to a sintering pallet, ignite the coke powder on the surface layer of the supplied sintering raw material, and extract the coke powder while sucking air downward. The iron ore powder is sintered by the combustion heat. In this way, the combustion of coke progresses from the upper layer to the middle layer and from the middle layer to the lower layer of the raw material layer, so that the lower the layer of the raw material layer, the more heat is accumulated and the temperature becomes higher, increasing ventilation resistance. the result,
The sintering reaction will proceed unevenly. Moreover, the upper layer of the raw material layer lacks heat, and a sufficient sintering reaction does not take place, making it brittle. The sintered mass sintered in this way is
During crushing and sieving, the upper layer was pulverized, causing a decrease in the sintering yield.

In order to eliminate the above-mentioned drawbacks, a method has been proposed in which the sintering raw material is charged so that the grain size is coarse in the lower layer and finer in the upper layer, and the amount of coke is increased in the upper layer. There is. Japanese Unexamined Patent Publication No. 63-206436 is one of such proposals, in which the lower side of a plurality of rod-shaped members has a single or plural chevron shape, and the mutual gap between the rod-like materials at the upper part of the chevron shape is formed by the rod-shaped lower part. The sintering raw material is supplied onto the sintering pallet through sieve surfaces arranged at different angles of inclination so as to be larger than the mutual gap between the materials, and the fine particles that have passed through the sieve surface or at a position immediately before the sieve surface are supplied. A carbon material or a mixture of a carbon material and a sintering raw material is added to the sintering material.

0004

[Problems to be Solved by the Invention] The present invention aims to improve the coke amount distribution in the vertical direction (or width direction) of the raw material layer on the pallet in order to improve the sintering yield and control the sintering reaction. The object of the present invention is to provide a means for adjusting the coke particle size distribution.

[0005]

[Means for Solving the Problems] The present invention aims to achieve the above-mentioned objects, and one of the objectives is to provide a sintered raw material that is charged onto a pallet so as to face the slope of the charging pile formed by the sintered raw material charged onto the pallet. For sintering, a plurality of blowing nozzles for blowing coke powder together with a carrier gas are provided at positions where the coke powder is blown into the raw material layer charged on the pallet. This is a method of adding coke powder.

Another method is to arrange the blowing nozzles toward the upper layer, middle layer, and lower layer of the raw material layer, and blow the coke powder from each layer nozzle while changing its particle size.
This is a method of adding coke powder for sintering.

[0007]

[Operation] A plurality of blowing nozzles are arranged at intervals on the same plane in the width direction of the raw material layer, and three rows of blowing nozzles are provided in the vertical direction of the raw material layer, so that each blowing nozzle By changing the amount of coke or coke particle size blown into each stage, it is possible to adjust the distribution of coke amount or coke particle size in the vertical direction of the raw material layer.

[0008] Coat is blown into the blowing nozzles in the width direction of each stage.
By changing the amount of coke or the particle size of coke, the distribution of the amount of coke or the distribution of coke particle size in the width direction of the raw material layer can be adjusted.

[0009]

EXAMPLES Examples of the present invention will be described in detail below. This example is an example of a method in which blowing nozzles are disposed toward the upper layer, middle layer, and lower layer of the raw material layer, and the particle size of the coke powder blown from each layer nozzle is varied and added. In FIG. 1, coke powder 1 crushed to 3 mm or less is passed through a vibrating sieve (1 mm opening) 3 (
Alternatively, it is sieved using a wind classifier (a wind classifier may also be used). Sieve top (
+1mm) 4 is in storage tank 8, under sieve (-1mm) 5 is in storage tank 7
will be temporarily stored.

[0010]Also, CDQ powder with a diameter of almost 0.25 mm or less (
Fine coke such as coke dust (2) generated from the coke dry digester is temporarily stored in a storage tank 6. The unsieved powder 5 in the storage tank 7 is cut out in a predetermined amount by a scale conveyor 10 installed under the tank, mixed with carrier gas (pressurized air, etc.) in a mixer 16 installed in a pneumatic pipe, and loaded onto a pallet. The sintering material to be charged is blown into the middle layer of the charging pile 24 from the blowing nozzle 18 provided at a position facing the slope of the charging pile 24 formed therein.

That is, it is added to the middle layer of the raw material layer. Similarly, the CDQ coke powder in the storage tank 6 is transferred to the scale conveyor 9.
After passing through the mixer 15, it is blown into the middle layer of the charging pile 24 from the blowing nozzle 19 provided near the upper layer on the side of the raw material pile 24, and added to the middle layer of the raw material layer.

Similarly, the sieved coke powder 4 in the storage tank 8 passes through the scale conveyor 11 and the mixer 17, and then flows into the charging pile from the blowing nozzle 20 provided near the lower layer on the side of the charging pile 24. It is blown into the lower layer of 24 and added to the lower layer of the raw material layer. Flow rate adjustment valves 12 to 14 are provided in the middle of the pressure air supply pipes of each mixer 15 to 17, and each scale conveyor 9
The amount of air can be adjusted according to the amount of coke powder cut out.

[0013] Efficient addition can be achieved if the nozzle tips of the blowing nozzles 18 to 20 are blown through the thin flow of raw material flowing down the slope of the charging pile. A plurality of blowing nozzles in each of the upper to lower layers are arranged at intervals in the width direction along the slope of the charging pile. FIG. 2 is a diagram illustrating the arrangement of the upper blowing nozzles and the distribution of the amount of coke powder supplied to each nozzle. In the figure, coke powder on a scale conveyor 9 is distributed by a distribution plate 25 provided on the conveyor head and supplied to each mixer 15.

The mixture is mixed with pneumatic pressurized air in the mixer 15, and blown into the upper layer through a plurality of blowing nozzles 18 arranged at intervals in the width direction of the charging pile. Here, since the amount of distribution is determined by the width b of the entrance of the distribution section, the distribution of the amount of added coke in the width direction of the raw material layer can be adjusted by changing the width b of each entrance of the distribution plate 25. The distribution of the amount of coke in the vertical direction of the raw material layer can be adjusted by changing the amount of cut-out of the scale conveyors 9-11.

The above-described lack of heat in the upper layer of the raw material layer reduces the cutting amount of the upper scale conveyor 9 between the middle and lower scales.
This problem can be solved by setting the number of conveyors to be larger than the number of conveyors 10 and 11. In addition, the lack of heat due to heat dissipation near the pallet side plates of the raw material layer is caused by the inlet size b of the partitions at both ends of the distribution plate 25.
This can be solved by increasing . Further, it is preferable to change the distribution of the amount of coke in the width direction and the vertical direction of the raw material layer according to the raw material conditions.

The following two methods can be considered as methods for adding coke powder. (1) Add the entire amount by the method of the present invention. (2) Addition by the method of the present invention and addition from a conventional blending tank are used together.

[0017]

[Effects of the Invention] Since the method of the present invention is constructed as described above, it has the following effects. (1) The distribution of coke amount in the width direction and vertical direction of the raw material layer can be reliably and easily adjusted. (2) The coke particle size distribution in the vertical direction of the raw material layer is also reliable.
Can be easily adjusted. (3) By (1) and (2), it is possible to improve the sintering yield and reduce the coke consumption rate.

[Brief explanation of the drawing]

FIG. 1 is a process diagram of the present invention.

FIG. 2 is an explanatory diagram of the arrangement of upper blowing nozzles and distribution of coke supply amount to each nozzle of the present invention.

[Explanation of symbols]

1 Coke powder 2　CDQ powder 3 Vibrating sieve 6-8 Storage tank 9-11 Scale conveyor 12-14 Flow rate adjustment valve 15-17 Mixer 18-20 Blow nozzle 23 Palette 24 Charging pile 25 Distribution plate

Claims (2)

[Claims] [Claim 1] A plurality of blowing nozzles for blowing coke powder together with a carrier gas are provided at positions facing the slopes of charging piles formed by sintering raw materials charged on a pallet.
A method for adding coke powder for sintering, which comprises blowing and adding coke powder into a raw material layer charged on a pallet. 2. Sintering according to claim 1, wherein blowing nozzles are disposed toward the upper layer, middle layer, and lower layer of the raw material layer, and the particle size of the coke powder blown from each layer nozzle is varied and added. How to add coke powder for use.