JPS62199733A - Sintering method - Google Patents

Abstract

PURPOSE:To increase a sintering speed and to improve the productivity of a vertical type sintering machine by supplying air for sintering adjusted in the concn. of oxyen to a raw material layer which consists of powder sintering raw materials and is formed in the vertical type sintering machine. CONSTITUTION:The powder sintering raw materials are charged by a charger 2 into the sintering machine body 1 of the vertical type sintering machine A to form the raw material layer 6. While the raw material layer 6 is moved downward, the air for sintering from an air intake port 27 is introduced through a main air feed pipe 28 and an air feed pipe 19 into the raw material layer and is supplied from below, by which sintering is executed. The exhaust gas generated by sintering is sucked and discharged by the blower 22 via an exhauster 4. The bottom end of the sintering completion zone formed by sintering is crushed by a crushing device 3 to obtain the sintered ore product. The concn. of the oxygen in the air flowing in the main air feed pipe 28 in the above-mentioned method is detected by an oxygen analyzer 32 and further the supply rate of the oxygen from an oxygen supply source 31 is controlled with a regulating valve 36 by an oxygen flow rate regulator 33 to control the concn. of the oxygen in the air for sintering. The sintering speed is thereby increased and the productivity is improved without deteriorating in produce quality.

Description

Detailed Description of the Invention "Field of Industrial Application" This invention relates to a sintering method for producing bulk sintered ore by sintering powdered ore, particularly for sintering when a vertical sintering machine is used. This is a note about the method.

``Toru - = J, t, station: +J?l Conventionally, when producing sintered ore for blast furnaces by sintering powdered ore, such as fine iron ore, a vertical sintering method as shown in Fig. 2 was used. Binding machine B is often used.

To explain this conventional vertical sintering machine B and the sintering method using it, this vertical sintering machine B has a sintering machine main body I,
The main components are a charging device 2, a crushing device 3, and an exhaust device 4. The sintering machine main body 1 has an ignition device 7.
7 to ignite and sinter continuously. That is, once the raw material layer 6 is ignited, sintering using it as a spark proceeds continuously at a position directly above the ignition device 7.7, and a sintered zone 8 is formed there. 8
The sintered zone 9 at the bottom of which has already been sintered is crushed by the crushing device 3.
By crushing and taking out the raw material layer 6, the raw material layer 6 is continuously sintered while falling at a predetermined speed due to gravity.

The crushing device 3 includes a sliding hammer I1. which moves back and forth from side to side in FIG. II crushes the lower part of the sintered zone 9, and the crushed products 12 fall through the product cooling hopper 13 and are transferred to a pan conveyor! 4 to be taken out. In addition, the charging device 2
The raw material 5 stored in the raw material hopper 15, 15 is fed into the sintering machine main body l by a drum feeder 16.degree. 16 in a predetermined amount in accordance with the descending speed of the raw material layer 6.

In addition to discharging exhaust gas generated during sintering, the exhaust device 4 also supplies a predetermined amount of sintering air to the raw material layer 6 through an air inlet provided at the bottom of the sintering machine body 1. tube 1
It is configured to be supplied from September 19th. That is, this ventilation device 4 directs the exhaust gas to the side surface 1a of the sintering machine main body 1.
, la through an exhaust pipe 18.18 and an exhaust fan (not shown) to suck and discharge the air. As the exhaust gas is sucked, sintering air necessary for combustion of coke contained in the raw material is sucked from the air introduction pipe 19.49 provided at the bottom of the product cooling hopper 13. ing.

Note that a grate 20.20 is attached to the oil level of the suction port 17.17.

According to this vertical sintering machine B, the sintering air sucked by the exhaust device 4 first cools the finished product 12, and then passes through the sintering completion zone 9 to cool these, and then flows into the sintering zone 8. As the sintering air is guided, the temperature of the sintering air itself is raised, and if sintering is carried out efficiently, heat is recovered. In addition, high-temperature exhaust gas from the sintering zone 8 is also removed from the suction port 17.
．． 17, the raw material layer 6 is preheated, so heat is recovered here as well.

[Problems to be Solved by the Invention] By the way, when using the conventional vertical sintering machine B, its productivity, that is, the sintering speed of the sintering zone 8 depends on the amount of water supplied to the sintering zone 8 by the folding screen device 4. This depends on the amount of sintering air being blown. In other words, the larger the amount of air blown, the more oxygen necessary for combustion of coke is supplied, thereby promoting combustion and increasing the sintering rate. Therefore, it is desirable to increase the amount of air blown as much as possible, but if the amount of air blown is too large, the velocity of the air passing through the raw material layer 6 becomes excessive, causing the raw material 5 to be blown up, resulting in a so-called fluid state, which reduces productivity. This may cause problems such as a decrease in the quality of the product or a decrease in the quality of the finished product. Therefore, in the past, air was only supplied at a wind speed that would not cause the raw material layer 6 to become fluidized, and no further improvement in productivity could be expected.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sintering method that can further improve productivity without deteriorating the quality of the finished product.

"Means for Solving the Problems" This invention charges a powdered sintering raw material into a vertical sintering machine from above to form a raw material layer, and moves this raw material layer downward. After sintering the sintering raw material while supplying sintering air from below the raw material layer and discharging the exhaust gas generated during sintering, the sintered product is crushed and the vertical sintering process is performed. A sintering method in which the material is taken out from below the sintering machine is characterized in that the sintering speed is controlled by adjusting the oxygen concentration in the sintering air supplied to the surface raw material layer.

"Example" An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a system diagram showing in particular the blowing system of the vertical sintering machine A used in the sintering method of this example. It is a signal line. First, this vertical sintering machine A will be explained. In this vertical sintering machine, the same components as those of the conventional vertical sintering machine B mentioned above are shown in Fig. 1 and shown in Fig. 2. Reference numerals are given and explanations are omitted.

In the ventilation device 4 of this vertical sintering machine A, the suction port 17
．． The exhaust pipes 18 and 18 connected to the main exhaust pipe 17 are each connected to a main exhaust pipe 21, and an exhaust fan 22 is connected to one end of the main exhaust pipe 21. This exhaust fan 22
The discharge side is connected to the chimney 23, and the inlet side is provided with a dust collector 24.

In addition, the reference numeral 25 is a flow rate adjustment valve that adjusts the amount of exhaust gas, and 26
is an exhaust gas analyzer.

On the other hand, air for sintering is taken in through an air intake port 27 equipped with a silencer and a filter, and is taken in through a main air supply pipe 28.
The air supply pipes 19 and 19 branch from this and are led to the lower part of the sintering machine main body 1. An orifice 29 for detecting flow rate is attached to the main air supply pipe 28.

Further, the exhaust device 4 of the vertical sintering machine A is equipped with an oxygen supply device 30 that supplies oxygen into the sintering air. This oxygen supply device 30 has an oxygen supply source 31, an oxygen analyzer 32, and an oxygen flow rate regulator 33 as main components, and is configured to blow oxygen from the oxygen supply source 31 into the main air supply pipe 28 through an oxygen pipe 34. It is being done. In the middle of the oxygen pipe 34 is a valve 35 and an oxygen flow ff1l regulating valve 36.
is attached, and the opening degree of this oxygen flow rate regulating valve 36 is controlled by an oxygen flow meter 33. The oxygen analyzer 32 also collects air from the main air supply pipe 28 through an introduction pipe 37, measures the oxygen concentration in the air, and sends the measurement result to the oxygen flow rate regulator 33. In other words, this oxygen supply device 30 is capable of blowing oxygen into the sintering air to increase its concentration (oxygen enrichment), and also maintains it at a constant value by measuring the oxygen concentration and performing feedback control. It is something that can be kept.

Above, the configuration of this vertical sintering machine A, especially the configuration of the air blowing system, has been described, but the other configurations are the same as the above-mentioned vertical sintering machine B, so the following explanation will be omitted.

Next, an example of a sintering method using the vertical sintering machine A described above will be described.

First, the oxygen flow rate adjustment valve 3 is set in advance by the oxygen flow rate adjustment meter 33.
6 is set to a predetermined value, and the total amount of sintering air blown (that is, the exhaust gas flow rate) is set to a value that does not cause the raw material layer 6 to be in a fluid state. Then, as in the case of the conventional vertical sintering machine B, after charging the raw material 5 into the sintering machine main body I using the charging device 2 to form the raw material layer 6, oxygen is supplied from the oxygen supply source 31. Sintering air is blown into the main air supply pipe 28 while controlling its concentration to a constant value,
The raw material layer 6 is ignited by the ignition device 7.7, and the crushing device 3 is driven.

As a result, sintering is performed continuously as in the past, and the combustion of coke in the raw material 5 is sufficiently promoted by the oxygen-enriched sintering air to increase the sintering speed.
Productivity improves. Since the total amount of air blown was set to such an extent that the raw material layer 6 did not become fluidized, the quality of the finished product I2 did not deteriorate, and the quality was not affected by oxygen enrichment, making it equivalent to the conventional product. A product 12 can be manufactured.

Furthermore, since productivity can be improved with the same amount of air blown as before, conversely, in order to obtain the same level of productivity as before, the amount of air blown can be reduced, and in this case, the capacity of the exhaust fan 22 etc. can be reduced. It is possible to reduce equipment costs and operating costs.

Although the present invention has been described in detail above, the present invention is not limited to the use of the above-mentioned vertical sintering machine A.
For example, any appropriate means may be used, such as blowing oxygen directly into the sintering machine body.

"Effects of the Invention" As explained in detail above, according to the sintering method of the present invention, the oxygen concentration in the sintering air is controlled, so that the sintering speed can be increased by increasing the oxygen concentration. This has the effect that productivity can be improved without reducing the quality of the finished product.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing the ventilation system of a vertical sintering machine used to carry out the method of this invention. FIG. 2 is a side sectional view showing a conventional vertical sintering machine. A... Vertical sintering machine, I... Sintering machine main body, 2... Charging device, 3... Crushing device,
4...Exhaust device, 5...Sintering raw material, 6.
... Raw material layer, 30 ... Oxygen supply device. Applicant Ishikawajima-Harima Heavy Industries Co., Ltd. Kawasaki Steel Corporation

Claims (1)

[Claims] Powdered sintering raw material is charged into the vertical sintering machine from above to form a raw material layer, and while this raw material layer is moved downward, sintering air is introduced from below the raw material layer. In the sintering method, the sintered raw material is supplied and sintered while exhaust gas generated during sintering is discharged, and then the sintered product is crushed and taken out from below the vertical sintering machine. A sintering method characterized by controlling the sintering speed by adjusting the oxygen concentration in the sintering air supplied to the sintering method.