JPS6347777B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for processing sintered ore and an apparatus therefor, which makes it possible to obtain sintered ore with excellent strength.

Conventionally, the method shown in FIG. 2 has been adopted as a method for treating sintered ore.

That is, a sintering raw material consisting of a mixture of granulated iron ore, limestone, coke, etc. is supplied from a hopper a to the upper part of a pallet conveyor type sintering machine b, and the coke in the supplied sintering raw material is sintered. The sintering raw material is sintered from the upper part by ignition combustion in the furnace c, and the cold air f sucked from the upper part of the sintering machine b by the exhaust blower e connected to the lower window box d of the sintering machine b produces coke. The sintered raw material is moved while the combustion is continued, and the sintered cake g is discharged from the sintering machine b.The discharged sintered cake g is crushed by a crusher h and then put into a cooler i. blower j
The crushed sintered ore is cooled and processed using the air supplied by the sintered ore.

However, in such cases, (i) After the sintering raw material leaves the ignition furnace, it is rapidly cooled by cold air, and cooling is extremely rapid especially in the upper layer, resulting in a lack of heat necessary for sintering. ,
Therefore, sufficient crystallization does not occur as a slag phase that serves as a sintering bond, and a brittle glass phase remains, resulting in a decrease in the strength of the product (sintered ore).

(ii) Due to rapid cooling, thermal strain occurs inside the sintered ore, making it easier to powder.

It had some disadvantages such as:

In order to eliminate the above-mentioned problems, rapid cooling of the sintering raw material is prevented by suctioning heated air with an exhaust blower e instead of the cold air f;
It has been considered to crystallize the sintered bond by slowing down the pallet speed of sintering machine b.

However, in the former case, the use of heated air increases the degree of reoxidation of the sintered raw material,
In other words, as the reoxidation area of the sinter structure increases, the
It has the disadvantage that the sintered ore is reduced to powder at a reduction temperature of ~600°C, reducing high-temperature strength, and in the latter case, productivity is simply sacrificed. This has the disadvantage that the sufficient effect of slowing down the speed cannot be obtained.

The present invention was made in view of the above-mentioned circumstances, and forms a horizontally moving packed bed which is a reheating bed using sintered ore that has been heated and sintered in a sintering machine and crushed into a required size after being discharged. A vertical moving bed, which is a cooling layer for the reheated sintered ore, is formed on the downstream side of the horizontally moving packed bed, and a part of the gas after passing through the sintered raw material of the sintering machine and the blast furnace gas are combusted. The sintered ore is heated to a temperature higher than that of the sintered ore in the horizontally moving packed bed by mixing a part of the high-temperature inert gas that cooled the sintered ore in the vertical moving bed to the combusted gas. Producing a reheating gas having a temperature that does not cause the ore to melt, sending the reheating gas to the horizontally moving packed bed to reheat the sintered ore in the packed bed, and reheating the ore. The remaining inert gas that is not mixed with the combusted gas among the high-temperature inert gas that cooled the sintered ore in the vertical moving bed is combined with the remaining inert gas, and heat is recovered from the combined gas. The method and apparatus for treating sintered ore are characterized in that the sintered ore that has been reheated and sent to a vertical moving bed is cooled by a low-temperature inert gas from which heat is recovered.

Embodiments of the present invention will be described with reference to the drawings.

1 is a sintering machine, and the upper part of one side is a feeding hopper 1
a and ignition furnace 1b, and sintering ventilation equipment 1c at the bottom.
A wind box 1d connected to the ore feed hopper 1a is installed to heat and sinter the sintering raw material (consisting of a mixture of granulated iron ore, limestone, coke, etc.) _m1 fed from the ore feed hopper 1a. A crusher 2, a sieve 3, and a hopper 4 are installed on the ore discharge side of the sintering machine 1, and the sintered cake _m2 from the sintering machine 1 is crushed and passed through the sieve. The ore is divided and fed to Hopper 4. The sintered ore _m3 from the lower discharge port 4a of the hopper 4 is loaded and moved from a moving grate 5a, and a reheater 5b reheats the sintered ore _m3 on the moving grate 5a. A heating device 5 is formed,
A wind box 6 is provided at the bottom of the reheating device 5.
However, a hopper 7 is provided on the ore discharge side, and a cooler 8 that forms a countercurrent vertical moving bed is provided below the hopper 7. A conveyor 9 is set below the outlet 8a to convey the cooled sintered ore to a required location.

Further, a pipe 10 connected to a blower 11 is connected to the lower part of the cooler 8, so that inert gas for cooling is fed by the blower 11, and a hopper 7 is connected to the upper part of the cooler 8. A pipe 12 for discharging high-temperature inert gas after heat exchange with sintered ore is connected to one end of the pipe 13 in which an air volume control valve 14 and a heat exchanger 15 are installed. It is connected via a primary dust remover 16 and a secondary dust remover 17, and the other end of the pipe 13 is connected to a boiler 18 for heat recovery.
8 are respectively connected to the blower 11 via piping 19 to form a cooling inert gas circulation line, and a bypass piping 20 is branched from the piping 19, and the bypass piping 20 connects to the blower 2.
1 and is connected to a chimney 22 through a blower 21 so that excess gas is bypassed and discharged from the chimney 22 by a blower 21.

Further, one end of a pipe 23 is connected to the reheater 5b of the reheating device 5, and the other end of the pipe 23 is connected to one end of a combustion blast furnace gas pipe 26 via a mixer 24 and a combustor 25. and the other end of the combustion blast furnace gas pipe 26 is connected to the heat exchanger 1.
5 and is connected to a blower 27 so that blast furnace gas for incineration can be sent to the combustor 25 by the blower 27, and a temperature detector 28 provided in the piping 23 and the air volume control valve 14 are connected to each other. The air volume control valve 14 is opened and closed as appropriate based on the detected value of the temperature detector 28.

Furthermore, one end of a combustion air pipe 29 is connected to the wind box 1d.
The other end is the primary dust remover 30 and the secondary dust remover 31.
The preheated air is connected to the combustor 25 through the blower 32 and the combustor 25 in turn.
5, and the other end of the pipe 33, one end of which is connected to the wind box 6, is connected to the pipe on the inlet side of the boiler 18 via a primary dust remover 34 and a second dust remover 35. 13, and the secondary dust remover 17 and the air volume control valve 14
The pipe 13 is branched between the boiler 18 and the branch pipe 36 is connected to the mixer 24, and the turbine 37 connected to the generator 38 is connected to the boiler 18.
The heat recovered in the boiler 18 is used for power generation.

Next, the effect will be explained.

The sintering raw material _m1 fed from the feed hopper 1a to the sintering machine 1 is ignited by the ignition furnace 1b to ignite the coke contained therein, and this ignition is continued by air suction by the sintering ventilation equipment 1c, and the sintering material m1 is sintered in this state. The ore is sent while being sintered and discharged from the sintering machine ₁ as a sintered cake m2. This discharged sintered cake m ₂ is crushed by a crusher 2 and sieved by a sieve 3 (for example, 5 mm
After the undersized ones are removed), the ore is fed to the hopper 4, and transferred from the discharge port 4a of the hopper 4 onto the movable grate 5a of the reheating device 5.
This transferred sintered ore m ₃ is heated to about 1000°C by the time it is discharged from the reheating device 5 by high-temperature inert gas of about 1100°C from the pipe 23 in the reheater 5b of the reheating device 5. The ore is then reheated to a temperature of 100.degree. C. and maintained at this temperature for a required period of time (for example, several minutes) before being discharged into the hopper 7. This discharged sintered ore is transferred to the cooler 8
and is cooled while exchanging heat with the rising low-temperature inert gas before reaching the outlet 8a.
The ore is discharged from a and transported to an appropriate location by a transporter 9.

Next, inert gas will be explained.

Approximately 180℃ via boiler 18 and piping 19
The low-temperature inert gas is passed through the pipe 1 by the blower 11.
The sintered ore is sent from the lower part of the cooler 8 through the sintered ore, rises while cooling the descending sintered ore, becomes a high-temperature inert gas of about 800° C., and is discharged to the pipe 12. Dust is removed from the discharged high-temperature inert gas by the primary dust remover 16 and the secondary dust remover 17, and part of the gas is mixed through the branch pipe 36 with the gas amount adjusted by the air volume control valve 14. The gas is sent to the mixer 24, where the temperature is adjusted, and the amount of gas used in the reheater 5b of the reheating device 5 is taken care of. On the other hand, the remaining high-temperature inert gas (the high-temperature inert gas that was not sent to the branch pipe 36) adjusted by the air volume control valve 14 passes through the pipe 13, joins the gas in the pipe 33, and flows into the boiler 1.
8, the boiler 18 recovers the heat, and the gas is turned into a low-temperature inert gas, which is sent to the cooler 8 from below by the blower 11. Further, the gas sent to the combustion blast furnace gas piping 26 by the blower 27 is preheated by absorbing part of the sensible heat of the high temperature inert gas that has passed through the piping 13 in the heat exchanger 15, and is sent to the combustion sinterer 25. At the same time, a part of the gas absorbed in the wind box 1d of the sintering machine 1 is transferred to the blower 32.
This leads to the combustion air pipe 29 and the primary dust remover 3.
0 and the secondary dust remover 31 and sent to the combustor 25, where the blast furnace gas piping 26 for combustion is removed.
and combustion air piping 29 are combusted. This combustion high-temperature exhaust gas and the high-temperature inert gas from the pipe 36 are mixed in a mixer 24 and the temperature is adjusted by a temperature sensor 28. That is, based on the detection signal of the temperature sensor 28, the air volume control valve 14 is opened. The temperature is adjusted and the amount of high-temperature inert gas flowing into the branch pipe 36 is adjusted, and when it reaches an appropriate temperature (approximately 1100°C), it passes through the pipe 23 and reaches the reheater 5b of the reheating device 5, where it is incinerated from the hopper 4. Carry out reheating of condensation m ₃ . Further, in the reheating device 5, a window box 6 is provided.
The high-temperature inert gas of approximately 1000°C sucked from the
After dust removal, the gas is combined with high-temperature inert gas from pipe 13 and sent to boiler 18, where the sensible heat is recovered as steam and becomes low-temperature inert gas at about 180°C. Furthermore, on the exit side of the boiler 18, the excess gas generated due to leakage in the combustor 25 and the reheater 5b is discharged from the chimney 22 by the blower 21, and the remaining amount becomes a certain amount and is removed by the blower 11. Heat is fed into the cooler 8 from below, while the heat recovered by the boiler 18 is used for power generation.

In addition to the embodiments of the present invention described above, the length of the sintering machine 1 is extended and the reheater 5b of the reheating device 5 is installed in this extension, so that the discharged ore from the sintering machine 1 can be recycled without being crushed. A method of heating and then crushing is also considered, but in such a method, there is a large resistance to ventilate the heated gas through the cake-shaped sintered ore (sintered cake), and cracks that occur in the sintered cake are This method has drawbacks such as unbalance of airflow easily occurring in the parts and surrounding areas of the pallet, making uniform heating difficult, and requiring the pallet to be made of a material with high heat resistance, which is uneconomical.

In the embodiments of the present invention, the case was described in which the temperature of the inert gas used to reheat the sintered ore was about 1100°C. Any number of times is acceptable as long as the temperature is higher than when the ore is input into the reheating device, and the discharge port 4a of the hopper 4 and the movable grate 5a of the reheating device 5
A sieving device is disposed between the sintered ore and the powdered sintered ore that cannot be turned into a finished product is discharged to the outside, and only the lump sintered ore is guided to the movable grate 5a, and the recovered heat is used for purposes other than power generation. It goes without saying that various changes may be made without departing from the gist of the present invention.

As described above, according to the sintered ore processing method and apparatus of the present invention, (1) Since reheating and cooling are performed using an inert gas, the room temperature strength of the sintered ore can be improved without impairing the reduction and powdering strength. Since the temperature of the gas supplied to the reheating layer can be easily adjusted, the sintered ore does not melt even during reheating, and the product quality of the sintered ore is improved.

() Conventionally, in order to increase the strength of sintered ore, the production rate of the sintering machine had to be reduced to some extent, but now the strength of sintered ore can be increased without reducing the production rate of the sintering machine.

() As shown in the figure, heat recovery means are provided, so
Sensible heat within the system can be used effectively, leading to energy savings.

() Since the reheating layer and the cooling layer are formed using crushed sintered ore, heat exchange can be performed more effectively than when the sintered ore is in the form of a cake.

(V) Since a horizontal reheating device is installed, the height of the entire device can be kept low.

Demonstrates excellent effects such as

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of a sintered ore processing apparatus according to the present invention, and FIG. 2 is an explanatory diagram showing a conventional sintered ore processing system. 1...Sintering machine, 2...Crusher, 5...Reheating device, 8...Cooler, 10, 12, 13, 1
9, 20, 23, 26, 29, 33, 36... Piping, 11, 21, 27, 32... Blower, 14
... Air flow control valve, 15 ... Heat exchanger, 18 ... Boiler, 24 ... Mixer, 25 ... Combustor, 28
...temperature detector, _m1 ...sintering raw material, _m2 ...sintered cake, _m3 ...sintered ore.

Claims (1)

[Claims] 1. A sintered ore that is heated and sintered in a sintering machine, discharged, and then crushed to a required size forms a horizontally moving packed bed that is a reheating layer, and the horizontally moving packed bed is A vertical moving bed, which is a cooling layer for the reheated sintered ore, is formed on the downstream side of the bed, and a part of the gas after passing through the sintering raw material of the sintering machine and the blast furnace gas are burned, and the combustion is performed. A part of the high-temperature inert gas that cooled the sintered ore in the vertical moving bed is mixed with the gas so that the temperature is higher than that of the sintered ore in the horizontally moving packed bed and the sintered ore does not melt. Make a reheating gas with a temperature of about
The reheating gas is sent to the horizontally moving packed bed to reheat the sintered ore in the packed bed, and the reheated gas and the sintered ore in the vertical moving bed are cooled to form a high-temperature furnace. The active gas is combined with the remaining inert gas that is not mixed with the combusted gas, and heat is recovered from the combined gas, and the heat is recovered and reheated by the low-temperature inert gas to form a vertical shape. A method for processing sintered ore, characterized by cooling sintered ore fed to a moving bed. 2. A sintering machine, a crusher for crushing the sintered ore from the sintering machine, a reheating device for reheating the crushed sintered ore, which consists of a reheater and a movable grate that moves laterally; A cooler that moves and cools the reheated sintered ore from the heating device from above to below, a line that includes a combustor and a mixer and supplies blast furnace gas to the reheating device, and gas discharged from the reheating device. and a line for cooling the sintered ore in the cooler and introducing the discharged inert gas together into the lower part of the cooler, a heat recovery device installed in the line, and a sintering machine. A line for supplying a part of the gas after passing through the raw material to the combustor, a line for supplying high temperature inert gas discharged from the cooler, and a line connecting the mixer are provided. A sintered ore processing device featuring: