JPS59129379A - Method of operating dwight-lloyd sintering machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of operating a Dwight Lloyd sintering machine, and particularly to a method of operating a Dwight Lloyd sintering machine that can produce a sintered ore product of stable quality.

A dotroid type sintering machine is generally used as an iron ore sintering machine, and an outline of the structure and operation of this machine will be explained with reference to FIG.

Raw materials 4 such as fine ore and coke limestone cut out from a plurality of blending tanks 2 are weighed by a violet-proof machine 6, mixed with water by a mixer 8, and stored in an ore feed hopper 10, which is installed below it at any time. It is fed through the gate 14 of the drum feeder 12 into the pan seat 16 passing below. A large number of barrels (16) constituting the sintering machine are connected and circulated on endless tracks from the ore supply section to the ore discharge section. The surface of the pallet 6 loaded with the raw material 4 by the drum feeder 12 is cut by the cut plate 18, and the pallet 6 is adjusted to different cuts tht20 in the width direction so that the suction wind speed is uniform in the width direction of the baren 16. The pallet 16 filled with the raw material 4 is ignited on the surface layer of the raw material 40 by the ignition furnace 22. Below the moving pallet 16, there are a plurality of wind boxes 24.
Each wind box 24 is connected to a main exhaust fan 26 to suck air through the raw material layer within the pallet 16. The sucked exhaust gas is discharged through the chimney 27 via the valve 25. As a result, the combustion front (hereinafter referred to as 1" FP) 29 of the raw material on the pallet 16 ignited by the ignition furnace 22 advances from the upper layer to the lower layer and ends in the vicinity of the ore discharge section 28.

In normal sintering operations, the point at which sintering completes (hereinafter referred to as BTP) is measured with a thermal coupler installed in the wind box 24, or it is detected from the component values of exhaust gas and the BTP is determined. Step 5: Check the moving speed of the pallet 16, the thickness of the raw material layer, the cutting fireflies, etc.

However, the above-mentioned DTP that was conventionally managed is an average value for the entire sintering machine, and in reality, depending on the width direction of the pallet 16, etc., the DTP may be past the unborn point of sintering or the past K B T P and enter the cooling zone. Unless the variation in sintering in the pallet width direction, which has the greatest influence, is minimized, it is not possible to obtain a sintered ore product of stable quality.

The measures conventionally taken to minimize the variation in BTP in the current width direction are as follows. That is, the first
As shown in the figure, the cut plate 1B is cut in front of the ignition furnace 22 to detect the second grade cut 2o so that the breathability of the raw material layer in the width direction of the pants 8160 becomes uniform. For this purpose, the ore feeding section gate 14 is divided into multiple parts in the width direction of the pallet, and by adjusting the opening degree of the gate 14, the amount of raw material supplied in the width direction of the pallet can be varied. As shown in Fig. 2, by adjusting the can cut by the cut plate I8 and t20, the air flow through the raw material layer is large in some parts and small in the central part, so the cut storm 20 increases the side wall part. The central part is small.

It is no exaggeration to say that such partially different air permeability in the width direction of the pallet depended solely on the intuition of the operator. Therefore, the temperature varies depending on the operator, and as a result, the permeability varies, which is a major cause of variations in the quality of the sintered ore product.

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional techniques in the operation of a Dwight Lloyd sintering machine, eliminate any reliance on human intuition, and calculate the passing wind speed using a computer based on accurate measurement data. The purpose of the present invention is to provide an operating method that can produce excellent sintered mineral products of stable quality.

The gist of the present invention is as follows.

That is, raw materials are loaded on the pallet moving on an endless track by adjusting the gate opening of the ore feeder, which is divided into a plurality of pieces in the width direction of the pallet, and imparts a uniform passing wind speed to the raw material layer. In a method of operating a Dwight Lloyd sintering machine having stages, the passing wind speed of the raw material layer is simultaneously measured at at least three locations on the raw material layer of the moving pallet in the width direction of the pallet, and calculating the average wind speed at at least three locations from the passing wind speed distribution in the machine length direction; calculating the passing wind speed distribution in the pallet width direction from the average wind speed;
5. A Dwight Lloyd sintering machine, comprising: (5) controlling a gate opening degree of the ore feeder so that the passing wind speed distribution in the width direction of the pallet becomes a preset passing wind speed distribution in the width direction; This is the operating method.

First, the wind speed measuring method and device according to the present invention will be explained with reference to FIG. The wind speed measuring device 30 includes a wind cover measuring device 32 installed across the pallet 16, a truck 32, and a connecting device 34 for connecting the truck 32 to the pallet 16. Run. On the other hand, three wind boxes 36 are straddled on the cart 32 in the width direction of the pallet 160, and the wind boxes 36 are attached to a wind box lifting arm 38 and can be raised and lowered by an M box lifting device 40. The wind box 36 is composed of an upper wind box 36A and a lower wind box 36B. I am in touch with you through.

At the bottom of the upper wind box 36A, there are an air volume measuring sensor and a temperature measuring sensor, which are connected to an anemometer 37.

When measuring the suction wind speed, the wind speed measuring device 30 is connected to the baren 16 by the coupling device 34, and as it moves, the track 4 provided outside the endless track 42 of the baren 1-16 is connected.
4, measure the wind speed while moving over a certain area, and after completing the measurement by moving over a certain area, disconnect from the pansoto 16 and run by the travel motor 35 to return to the original measurement starting position.
It is configured to be able to continuously measure the suction wind speed in the longitudinal direction.

With the wind speed measurement device 30 having such a configuration and function, it is possible to know the wind speed distribution in the longitudinal direction of the sintering machine from the exit side of the ignition furnace 22 to the ore discharge section 28 and in the width direction of the barrel 16. Since the measured wind speed value at each position in the machine length direction and width direction depends on the ventilation resistance in the raw material layer 4, it is possible to know the air permeability distribution in the machine length direction and pallet width direction from the expected wind speed distribution. You can do it.

Generally, when the air permeability is good, the wind speed passing through the raw material layer 4 increases, the combustion front velocity (hereinafter referred to as FFS) becomes faster (the high temperature holding time becomes shorter, and the cold strength of the sintered ore product decreases). Although this is a well-known fact, the experimental results of the present inventors support this as shown in Figure 4. Figure 4 shows the relationship between the combustion front velocity (FFS) and the cold temperature of sintered ore. It is a correlation diagram showing the relationship with intensity, and straight line A is shown by equation (1).

Y = -0,323x + 99.2...(1
) In this experimental result, there are cases where R=-0,72-37, which indicates that the cold strength decreases as the FFS increases.

Generally, FFS is expressed by the following equation (2).

F F S = Hx P S / B 1' P
, - (2) where 14 = Sintering raw material layer thickness PS: Pallet speed K BTP: Distance from sintering start point to completion point Therefore, in order to stabilize the quality of the sintered ore product, the button is pressed by the sintering machine captain. It is necessary to stabilize the BTP by stabilizing the distribution of air permeability in the direction, and it is also extremely important to equalize the passing wind speed in the width direction and keep the FFS constant.

Next, the average wind speed as shown in FIG. 5 was obtained from the measured wind speed distribution measured during the instant sintering process of the sintering machine by the present inventors using the air flow measurement device f30 having three wind boxes 36 as shown in FIG. F
I was able to seek a relationship with FS. Directions shown in Figure 5
B is represented by the following equation (3).

y = 0.477 x +17. ! ...(3
) This experimental result was obtained at I(=0.86 -37. Therefore, using Figure 5, measure the wind speed distribution in the longitudinal direction during the sintering process and find the average wind speed. This allows you to know FFS@.

Next, it has become clear that there is a good correlation between the change in the cut amount of the charged raw material and the change in the average wind speed, as shown by the straight line C in FIG. Straight line C is expressed by the following equation (4).

y=o, o 76 x+0.517...(4) In this experiment, EC=0.87 -30. Therefore, it has been found from FIG. 6 that it is possible to arbitrarily change the passing wind speed by changing the amount of cut.

From the correlation shown in Figure 4.5.6 above, the FFS corresponding to the sintered mineral product having the target cold strength is determined from Figure 4, and then the target corresponding to the F'PSK is determined from Figure 5. As shown in the block diagram simultaneously shown in FIG. A wind speed distribution is determined, and from this passing wind speed distribution, an individual average wind speed at at least three locations on the upper side is determined, and then a passing wind speed distribution in the pallet width direction is determined from this average wind speed.

If the actually measured passing wind speed distribution in the pallet width direction is different from the preset passing wind speed distribution in the pallet width direction, the gate 14 of the ore drum feeder 12 at the relevant location is opened based on FIG. By adjusting the degree of cutting and changing the amount of cut at the corresponding location, it is possible to equalize the passing wind speed in the width direction of the pallet 160, and by the control method according to the present invention, it is possible to make the passing wind speed uniform in the width direction of the pallet 160. It is now possible to ensure quality sintered ore products.

Example: During normal operation, the passing wind speed of the raw material layer was measured simultaneously at three locations on the north side, center, and I@ side in the width direction of the pallet, and the passing wind speed distribution in the longitudinal direction was measured according to the progress of the pallet's movement from the exit side of the ignition furnace. As a result, the results shown in FIG. 7 were obtained. This example shows that the average wind speed at the north and inner ends is smaller than at the center.

The target average wind speed for this lifting platform was between the center and both ends of the inner milk, so the cut amount was slightly increased in the center and decreased at both ends to reach this set value. As a result of adjusting the opening degree of the feeder, it was possible to obtain a passing wind speed distribution in the machine length direction as shown in FIG. 8, and it was possible to extremely reduce the variation in passing wind speed in the pallet width direction.

As a result, the produced sintered mineral products were able to ensure stable quality.

As is clear from the above examples, in the conventional operating method of the DL type sintering machine, there was no sensor to detect the air permeability in the width direction of the pallet, so the amount of cut in the width direction of the pallet was determined by individual differences depending on the intuition of the operator. many, so accurate a
However, according to the present invention, the wind speed passing through the raw material layer is simultaneously measured at at least three locations in the width direction of the pallet, and the wind speed distribution in the machine length direction is determined. Determine the average wind speed at the 31 station, calculate the passing wind speed distribution in the pallet width direction from this average wind speed, and adjust the gate of the ore drum feeder so that the measured distribution approaches the preset target passing wind speed distribution in the pallet width direction. Since the amount of cut is controlled by adjusting the opening of the f#IJ? 4 became possible, and the variation in average wind speed in the width direction of the pallet became extremely small, making it possible to ensure excellent and stable quality in the manufactured sintered ore products.

[Brief explanation of the drawing]

Fig. 1 is a schematic cross-sectional view of the main equipment of the sintering machine and a block diagram of the sintering operation showing the operating method of the Dwight Lloyd sintering machine according to the present invention, and Fig. 2 shows the distribution of cut plates in the width direction of the pallet according to the present invention. FIG. 3 is a perspective view showing an example of the airflow measuring device for a sintering machine according to the present invention, and FIGS. 4 to 6 are phase flash diagrams obtained from experimental results for obtaining the present invention. is the correlation between the pallet pre-combustion winning speed ()'FS) and the cold strength of the sintered ore product, Figure 5 is the correlation between the average wind speed and 1. Figures 7 and 8, diagrams showing the correlation with changes in average wind speed, show examples of the present invention, and Figure 7 shows three points in the pallet width direction (north flt, center, FIG. 8 is a diagram showing the wind speed distribution at three points in the width direction of the pallet after adjusting the cut amount tA according to the present invention. 4... Raw material, 12... Ore drum feeder, 14
... Kate, 16 ... Pallet, 22 ... Ignition furnace, 24 ... Wind box, 30 ... Wind speed measurement device, 36 ... Wind box, 42 ... Endless track, 44 ...・
bogie track. Agent Patent Attorney Takeo Nakaji FFS (hat n/m1n) Change in cut 11 (WIrn) (・'/'1%) r sound tp h

Claims (1)

[Claims] (1) Loading raw materials onto a pallet moving on an endless track by adjusting the gate opening of the ore feeder divided into a plurality of pieces in the width direction of the pallet, and imparting a uniform passing wind speed to the raw material layer. In the method of operating a Dwight Lloyd sintering machine, the wind velocity passing through the raw material layer is simultaneously measured at two locations on the raw material layer of the moving pallet in the width direction of the pallet, and determining a passing wind speed distribution;
calculating an average wind speed at the at least three locations from the passing wind speed distribution in the machine length direction; determining a passing wind speed distribution in the pallet width direction from the average wind speed; and setting the passing wind speed distribution in the pallet width direction in advance. A method of operating a Dwight Lloyd sintering machine, comprising the step of: controlling gate opening of the ore feeder so as to achieve a passing wind speed distribution in the width direction.