JPS6148539A - Operating method of sintering machine - Google Patents

Abstract

PURPOSE:To stabilize and improve the quality of sintered ore and to increase the quantity of the waste heat to be recovered by tracing calcination for each of pallets or pallet groups and controlling the waste gas temp. for each of wind boxes from a raw material charging part to an ore discharging part according to the calcination speed in such stage. CONSTITUTION:The calcination is traced by detecting the waste gas temp. for each of the pallets 1 or pallet groups by a waste gas temp. measuring device 9 provided to the downcomer 7 of each wind box 3 in a DL type sintering machine. The pattern of the waste gas temp. obtd. by such tracing of the calcination is compared with the reference waste gas temp. A shown in the graph and if the calcination is faster or slower, the opening degrees of the downcomer dampers 8 are controlled to attain set temps. T1-T22 by a waste gas temp. control device 15, thereby controlling the waste gas flow rate for each of the pallets 1 or pallet groups. As a result, the variation in the calcination is decreased and the quality of the product sintered ore is considerably improved and stabilized.

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention improves the quality of sintered ore by stabilizing the firing of sintering raw materials by controlling the wandering temperature of each wind box in a DL type sintering machine. Concerning the operating method of the measuring sintering machine.

Prior Art and Its Problems The firing conditions of sintered raw materials in a DL type sintering machine vary greatly due to variations in the blended raw materials, fluctuations in the moisture content of the raw materials, occurrence of cracks, and the like. Figures 4 and 5 illustrate examples of exhaust gas, single pattern, and exhaust gas amount pattern, respectively.
Assuming that the solid lines are the basic heat pattern and basic air flow pattern, respectively, when the firing speed is high, the dashed lines AIi and BH, respectively.
If the firing speed is delayed, the changes will be as shown by broken lines Aw and Bw, respectively. Furthermore, since the firing situation has conventionally been controlled by the pressure or air volume of the main exhaust fan or the circulation fan of the exhaust heat recovery system, the effective air volume for firing for each pallet differs greatly. Therefore, in the case of a DL type sintering machine, due to these reasons, the sintering is unstable and the quality of the sintered ore varies widely, and the heat content of the sintered ore also varies greatly from pallet to pallet, making it difficult to use the exhaust heat recovery system. This will also cause large fluctuations in the steam generated by the main boiler and cooler boiler.

Purpose of the Invention The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to propose a method of operating a sintering machine that can stably improve the quality of sintered ore and increase the amount of waste heat recovered. This is the purpose.

Structure of the Invention The method of operating a sintering machine according to the present invention traces the firing of sintered ore for each pallet or for each group of several pallets using an exhaust gas temperature measuring device installed in the downcomer pipe of each wind box. This method is characterized in that the amount of exhaust gas is controlled by a downcomer pipe damper in accordance with the firing speed, and the temperature of the exhaust gas in the windbox is controlled.

In other words, the present invention grasps the slowness of the firing speed based on the exhaust gas temperature measured for each wind box, and controls the fluctuation of the firing speed by controlling the exhaust gas amount of the wind box for each pallet or pallet group to control the exhaust gas temperature. This is a method of stabilizing through control.

In the case of a DL type sintering machine, it is possible to judge whether the firing speed is fast or slow based on the temperature of the windbox exhaust gas from the raw material charging section to the ore discharge section, so the actual heat can be determined based on the basic heat pattern. Firing can be stabilized by controlling the exhaust gas temperature for each wind box to change the pattern.

Hereinafter, the method of this invention will be explained in detail with reference to the drawings. Figure WJ1 is a schematic diagram schematically showing a DL type sintering machine equipped with a sintering main exhaust gas heat recovery circulation system. The raw material is transported to the ore discharge section by the movement of pallets while forming a packed bed on the V-gate, and during this time, the surface of the packed bed is ignited in an ignition furnace (2). On the other hand, each wind box (3
), the combustion gas is forcibly drawn from below the packed bed by the main exhaust fan (4). This suction power is generated by the main exhaust duct (5
) is adjusted by the opening degree of the damper (6). The descending pipe (7) of the Tanikaze box has a damper (8) to control the amount of exhaust gas and a wave e (9) for measuring the exhaust gas temperature.
is installed.

The main exhaust gas heat recovery circulation system is designed to increase the efficiency of heat recovery by returning the main exhaust gas to the sintering machine once the heat has been recovered. After heat recovery, the gas is guided above the sintering machine pallet using a circulation fan αD, and returned to the sintering machine through a hood coffin installed above the pallet, where it is circulated and used as combustion gas. Of course, this synutem is known.

Figure 2 is a schematic diagram showing the exhaust gas temperature control system.
, (to) controls the downcomer damper (8) of each wind box based on the detected value of the exhaust gas temperature measuring device (9) installed on the downcomer pipe (7) of each wind box (3). The exhaust gas temperature control device (to) determines whether to control the pallet speed or the rotation speed of the main exhaust fan (4) or circulation fan 11) when the exhaust gas temperature goes out of the control range. (171 is the main exhaust fan rotation speed control system, 08 is the pallet speed adjustment device, and α0 is the circulation fan rotation speed control system.

Effect of the Invention In a sintering machine equipped with the above-mentioned equipment, the downcomer pipe (7
) The exhaust gas temperature is detected for each pallet or for each group of pallets by the exhaust gas temperature measuring device (9) installed in the oven, and baking tracing is performed. Compare the exhaust gas temperature pattern obtained by this firing trace with the basic and one-dot patterns (standard exhaust gas temperature) (A) shown in Figure 3, and if the firing is fast,
Alternatively, if the firing is slow, the exhaust gas temperature control device (2
) to set the temperature T1~T! The amount of exhaust gas is controlled for each pallet or for each group of pallets by adjusting the opening degree of each downcomer damper (8) so that the amount of exhaust gas is 2.

In addition, if the exhaust gas temperature control is outside the control range,
For example, if the downcomer pipe damper (8) of the wind box &2 to &22 is fully opened, but the exhaust gas temperature does not rise and the firing speed is delayed, the pallet speed may be slightly slowed down by the computer (161), or ■The rotation speed of the main exhaust fan (4) or circulation fan αυ is controlled by each control system Uη, α.
This can be dealt with by increasing the exhaust air pressure.

Conversely, the downpipe damper (8) of wind box 22 to NL2
If the firing speed increases even when the is fully closed, take the opposite action to the above.

Effects of the Invention As described above, the method of this invention traces the firing of each pallet or pallet group, and measures the wandering gas temperature in each wind box from the raw material charging section to the ore discharge section according to the firing speed at that time. Since it is a control method, it is possible to reduce variations in firing, and it is possible to greatly improve the quality of the finished sintered ore, and it is also stabilized. In addition, the heat content of the sintered ore from pallet to pallet during the firing process does not vary significantly, so there are fewer fluctuations in the steam generated in the main boiler for waste heat recovery and the waste heat boiler for the cooler. It also becomes possible to further increase the amount. moreover,
By stabilizing firing, it is possible to save power for the main exhaust fan and the fans in the exhaust heat recovery system, which is also an effective measure for energy conservation.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a DL type sintering machine which is the subject of this invention, Fig. 2 is a schematic diagram showing an exhaust gas temperature control system for carrying out the method of this invention, and Fig. 3 is a DL type sintering machine. FIG. 4 is a chart showing an example of a basic heat pattern of exhaust gas, FIG. 4 is a chart showing an example of a heat butter pattern of exhaust gas, and FIG. 5 is a chart showing an example of an exhaust gas amount pattern. 1... Pallet, 2... Ignition furnace, 3... Wind box, 4... Main exhaust fan, 5... Main exhaust duct, 7
...Down pipe, 8...Down pipe damper, 9...
- Exhaust gas temperature measuring device, 15...Exhaust gas temperature control device, 16...Computer, 17...Main exhaust fan rotation speed control system, 19...Circulation fan rotation speed control system. Figure 3 22 2120:19181716151413121
110 9 8 7 6 5 4 3 2 1 Kazehakoya Figure 4 Figure 5 Offering side

Claims (1)

[Claims] In a sintering machine equipped with an exhaust gas temperature measuring device on the downcomer pipe of each wind box, the sintered ore is traced for each pallet or several pallet groups, and the exhaust gas is controlled by a downcomer damper according to the firing speed. A method of operating a sintering machine characterized by controlling the amount and controlling the temperature of wind box exhaust gas.