JPS6156024B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the provision of new means for grinding iron ore into sinter raw materials of less than 10 mm or less than 8 mm.

When iron ore is pulverized into a raw material for sintered ore, a pulverization method using a rod mill is currently generally employed, but this pulverization method has the following problems. In other words, the wear of the rod is large, and the rod is
When the rod wears down to about 50mmφ, it will break during movement, so rods must be frequently replaced and taken out and put in and out, leading to a decrease in operating efficiency, and poor rod yields also lead to increased running costs. It is. Furthermore, as the inner diameter of the mill chamber increases, the number of rod breakage accidents increases, so there is a limit to the machine size of the rod mill itself.For this reason, as the throughput increases, it is necessary to increase the number of rod mills installed instead of increasing the size of the rod mill. This results in disadvantages such as an increase in the size of the entire equipment and a significant increase in power consumption.More common disadvantages of this type of rod mill system are that the processing capacity is small compared to the machine size, and the product Other factors include high power consumption per unit and high operating noise.

The present invention solves these problems and makes it possible to obtain iron ore raw material for sintering with a desired particle size with high efficiency using a cone crusher that is functionally less abrasive and easy to maintain. The special feature is that iron ore classified under 40mm and over 8mm,
Adjust the outlet opening gap to 1 to 1.3 times the product size.
And the eccentric momentum is 0.02 to 0.03 (0.03
The present invention is configured to continuously crush the cone crusher while supplying the cone crusher with a feed rate approximately equal to the theoretical maximum throughput.

The present invention will be described in detail below based on the illustrated embodiments. FIG. 1 shows an overall flow sheet diagram as an embodiment of the method according to the present invention.
1 is a raw material bottle, and although it is not shown in the raw material bottle 1, 40
The raw iron ore classified within the range of 8 mm or less is stored, and the bin is equipped with a level gauge to ensure that a certain amount or more of the classified ore raw material is always kept in the bin. , which enables continuous operation of the cone crusher. The feeder 2 installed below the raw material bin 1 is of a variable feeder type, the amount of which is taken out can be changed arbitrarily by a signal from the cone crusher, and the ore raw material taken out by the feeder 2 is sent to the cone crusher 3. It is then crushed. The cone crusher 3 is equipped with an automatic setticator to automatically control the outlet opening gap to a set value of 1 to 1.3 times the product size, as described later, and is equipped with an even supply device. The ore raw material is supplied to the entire circumference of the crushing chamber, and a signal is taken out from the operating hydraulic circuit and/or drive motor of the cone crusher 3 to interlock with the feeder 2, so that the theoretical maximum passage of the crusher can be achieved while protecting the crusher. The cone crusher 3 is provided so as to continuously operate at maximum capacity. The iron ore products for sintering thus crushed and sent out by the cone crusher 3 are sieved by a vibrating sieve 4 to a predetermined particle size of 10 mm or less or 8 mm or less, and oversized ones are passed to a return device 5. Then again, raw material bottle 1
It is then sent back to Japan for re-shredding.

Here, the cone crusher 3 used in the present invention differs from conventional cone crushers in that the opening gap on the outlet closing side of the crushing chamber is 1 to 1.3 of the product size.
It is different from conventional cone crushers in that the eccentric momentum is set in the range of 0.02 to 0.03 (excluding 0.03) of the diameter of the rotating body.

That is, as a typical example is shown in FIG. 2, the conventional cone crusher has a crushing chamber 23 formed by a conical cone cave 21 and a mantle 22 that eccentrically rotates inside the cone cave 21. The raw material to be supplied is subjected to repeated compressive loads by the rotation of the mantle 22 in the process of falling in the crushing chamber 23, and while repeated crushing, the gap between the mantle 22 and the outlet closing side opening 24 regulated by the cone cave 21 is created. When the iron ore raw material is crushed to a particle size and size approximately equal to C, it is discharged from the machine through the outlet opening 24. However, when using this type of cone crusher to crush iron ore raw material as raw material for sintered ore, conventional The gap C of the outlet closing side opening 24 is 6.5 mm.
By reducing the particle size to a smaller size, the desired fine-grained product was obtained. This is because the gap C between the outlet closing side opening 24 is set as small as possible in order to increase the product ratio, but this results in a decrease in the amount of passage through the crusher and a decrease in the product production volume, that is, the throughput. Even a small amount of moisture in the iron ore raw material tends to cause overload, making it difficult to mass-produce through continuous processing.

In the present invention, in order to improve this point, it is possible to reduce the size of the product from 1 to
By setting the raw ore supply amount to the crusher to be approximately equal to the theoretical maximum passing amount, that is, the maximum supply amount, and causing a packing phenomenon in the crushing chamber.
Therefore, in the present invention, the corn cave 3 is used as the corn crusher 3.
A crushing chamber 33 is created by the mantle 32 which performs an eccentric rotation movement around the center axis of the cone cave 31 in the same cave 31 as shown in FIG. 34 indicates the opening on the exit closing side. In other words, in order to increase product production, it is necessary to increase the amount of rough ore passing through the crusher, but on the other hand, it is necessary to satisfy the conflicting demands of increasing the product content of the desired particle size relative to the amount of rough passing through the crusher. However, the former amount of passage can be increased by increasing the gap between the outlet closing side openings, thereby reducing the eccentric momentum of the mantle 32 and the crushing chamber 33.
The shape of the crusher uniquely determines the calculated throughput per unit time (T/h) of the crusher, and the latter requirement can be solved by providing a sufficiently high density and high compression ratio in the crushing chamber 33. It will be possible. Therefore, as in the present invention, if the gap C of the outlet closing side opening 34 is increased and the eccentric momentum e of the mantle 32 is set accordingly, the amount of material passing through the crusher 3, in other words, the crushing process can be reduced. If the amount to be processed is determined, and this processing amount is continuously supplied into the crushing chamber 33, the raw material will fall and flow in a compacted packed state at each position in the crushing chamber length H direction within the crushing chamber 33, and the raw material will fall and flow into the crushing chamber. While maintaining the consolidated layered fluidity state of the raw material in 33,
When compressed by swirling with the mantle 32, sufficient high density and high compression ratio are given to the raw material, and suitable crushing can be obtained. In addition, in order to carry out such crushing, it is necessary to more effectively propagate the compressive load to the raw material in the crushing chamber 33 between the layers, and this requires the above-mentioned method. In the present invention, by supplying a sufficient amount of raw material to the crushing chamber 33 in the crushing chamber 33, the mantle is The amount of work due to the eccentric rotation movement of 32, that is, the compressive load on the raw material, is propagated between the layered raw materials in a compressed state, and as a result, fracture occurs from the raw stone with low strength, and this process is repeated and progresses within the chamber 33. , until the mantle 32 reaches the position closest to the cone cave 31 with the eccentric momentum e shown by the imaginary line in the figure, the raw material is compressed in a layered state, causing a fracture phenomenon that can be called layer compression fracture, and producing the desired result. Particle size crushing can be carried out continuously and efficiently.

In addition, the outlet closing side opening gap c and the eccentric interlocking amount e
If the value of is made larger than that of the present invention, it is possible to further increase the production amount, but the return amount also increases and becomes 3 to 5 times the product amount.

That is, FIG. 8 shows the outlet closing side opening gap c,
This is a graph showing the relationship between raw material passage capacity and product production volume.If the exit closing side opening gap c is made too large, the passage capacity will increase, but the product production volume will not increase in proportion to it, and the return volume will decrease. It can be seen that the number is increasing. Therefore, the outlet closing side opening gap c
It can be seen that the numerical values of the present invention are optimal.

The present invention is as described above, and what is shown in FIGS. 4 and 5 is a product produced according to the present invention,
A comparison diagram of particle size distribution with products made by conventional Rod mills is shown. The iron ore brand shown in Figure 4 is Yampi Sound, and the brand of iron ore shown in Figure 5 is Riodoce. In the figure, the dotted line is the product produced by the conventional rod mill, and the solid line is the product produced by the present invention.As is clear from the figure, the particle size distribution of the present invention is approximately the same as that of the product produced by the conventional rod mill. It is something that was given. Also, Figures 6 and 7 show the crushed particle size diagrams when the same brand of ore is crushed, with the gap of the outlet closing side opening being 6.5 mm and 9.5 mm. shows the brand Yampi Sound, and Figure 7 shows the brand Rio Doce, and the test numbers and symbols are as shown in the appendix to the drawing. In other words, as is clear from both figures, if the feed rate of the raw material is sufficiently large according to the method of the present invention, even a product with a gap of 9.5 mm at the outlet closing side opening will be on the same level as a product with a gap of 6.5 mm, or even better. This makes it possible to obtain fine grains, and the method of the present invention also enables mass production. That is, as is clear from the above implementation results, according to the method of the present invention, when crushing and manufacturing iron ore raw material for sintering from raw iron ore, products with desired particle size can be mass-produced more efficiently than conventional methods. By solving the problems of the rod mill method and adopting the cone crusher method, which has less wear and tear and is easy to maintain, the necessary equipment itself can be significantly simplified, making it possible to economically produce iron ore raw materials for sintering. Furthermore, if the device according to the present invention is incorporated into ore sizing equipment, it can contribute to increasing the production volume of the sizing equipment, and it has great utility as a means for crushing coin raw materials such as iron ore.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet diagram of an embodiment of the method of the present invention;
Fig. 2 is an explanatory diagram of a conventional cone crusher, Fig. 3 is an explanatory diagram of a cone crusher used in the present invention, Figs. 4 and 5 are comparison diagrams of particle size distribution of each product by the method of the present invention and the rod mill method, and Figs. 6 and 7 are illustrations of the outlet. FIG. 8 is a graph showing the relationship between the opening gap on the closed side of the outlet, the passage capacity, and the product production amount. 1... Raw material bottle, 2... Feeder, 3... Corn crusher, 4... Vibrating sieve.

Claims (1)

[Claims] 1. Iron ore classified into 40 mm or less and 8 mm or more is set so that the opening gap on the closed side of the outlet is in the range of 1 to 1.3 times the product size, and the eccentric momentum is 0.02 to 0.03 of the diameter of the rotating body.
A method for producing an iron ore raw material for sintering, which comprises continuously crushing the raw material of iron ore for sintering while supplying it to a cone crusher set in the range of 0.03 (excluding 0.03) at a feed rate almost equal to its theoretical maximum throughput.