JPS58213836A - Method for determining optimum extent of operation under operational condition during operation of sintering apparatus - Google Patents

Abstract

PURPOSE:To allow a sintering apparatus to rapidly cope with a change in the volume of wind and to stabilize quality by determining the optimum extent of operation with respect to the speed of the pallet or the thickness of a layer from the estimated desired volume of wind in a sintering model based on the operational state of the sintering apparatus such as the measured values of the speed of wind. CONSTITUTION:The measured values of the speed of wind obtd. from wind gauges placed at four or more positions of the wind box section of a Dwight- Lloyd type sintering apparatus or the surface of the apparatus, the speed of the pallet, the thickness of a layer and negative pressure by suction are inputted in a sintering model, the desired volume of wind to be sucked is estimated by calculation, and the optimum extent of operation for attaining the desired volume of wind with respect to the speed of the pallet or the thickness of the layer is determined to control the operational conditions of the sintering machine. Thus, the desired volume of wind is accurately attained in a short time, and quality can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for determining the optimum operation amount for operating conditions in sintering machine operation, and more specifically, in order to suppress ventilation fluctuations, the present invention relates to a method for achieving a target suction air volume predicted based on a sintering model in order to suppress ventilation fluctuations. The purpose of this study is to propose a method for determining the optimal operating amount of pallet speed or layer thickness.

Fluctuations in ventilation during sintering machine operation using a Dwight Lloyd type sintering machine (hereinafter simply referred to as sintering machine) are mainly caused by fluctuations in raw material particle size and coke blending ratio, and the changes in sintered ore strength and reduction disintegration properties etc., leading to variations in the quality of sintered ore. Therefore, in order to stabilize the quality of the sintered ore, various operations have been carried out to suppress the air permeability fluctuations. Among these, operations for changing layer thickness and pallet speed are particularly frequently used. In general, if the ventilation is too good, increase the layer thickness or pallet speed, and if the ventilation is poor, decrease the layer thickness or pallet speed to adjust the suction air volume and negative pressure pipe. within a certain range,
We maintain equipment and stabilize quality. Conventionally, it has been impossible to predict how much the J suction air volume will change after the operation of changing the thickness. Therefore, the pallet speed or layer thickness cannot be changed within a certain range, and the operation tends to be delayed in response to operational fluctuations.

As mentioned above, the present invention aims to make it possible to predict the suction air volume after changing the layer thickness and pallet speed, which was previously impossible, and to quickly reach the predicted target air volume. By inputting the measured wind speed, pallet speed, layer thickness, and suction negative pressure into the sintering model and predicting them, and determining and implementing the optimal change operation amount to reach the predicted target air volume, By quickly changing the operation of the sintering machine, we were able to achieve the above objectives.

Next, the method of the present invention will be explained in detail.

The present inventors previously proposed a method for detecting the progress of sintering inside a sintered layer in Japanese Patent Application No. 16291/1982, but the present invention further develops the above invention to suppress airflow fluctuations. The present invention provides a method for predicting the optimum suction air volume and determining the optimum pallet speed or layer thickness operation to quickly achieve the predicted target air volume.

In the detailed explanation of the above-mentioned Japanese Patent Application No. 56-141291, the wind speed distribution formula in the longitudinal direction of the sintering machine is described as follows (1), 1 and (
2) It is shown by the formula. That is, when X<L, = 0
R8HO”HEN (7)
D-n'RNKN
(8) QF, QB: Wind speed passing through the sintered layer (m, /a+in
) PS: Pallet speed (m/m1n) ΔP: Negative suction pressure (Kaku H20) (mmH, o-m
1n"y,, L4)"HEN" Ventilation resistance index of combustion zone R8HO" Ventilation resistance index of sintering zone, KB: Wind speed coefficient (to) Lo: Sintering completion position (m) Said patent application 1982-16291 In the publication ``Method for detecting sintering progress inside a sintered layer'', based on this model, the parameter RGEN of the model is calculated.

Although the method of continuously obtaining R□N, R8HO, KF, KB'ft from the wind speed measurements at four points in the longitudinal direction of the sintering machine has been shown, the present invention will be explained below.

From equations (1) and (g), the total suction wind ji ('I'Q)
can be expressed by equation (9), where ML is the length of the sintering machine (7FL) ◇The parameters of TQ are ps, ΔP, H' RGEN , RNEW
.

It consists of R8Ho, KF, and KB, all of which are known values.

Therefore, when changing the pallet speed at a certain point in time, the other parameters except ΔP can be considered constant, and the suction air volume (T'Q) is ultimately given by equation (1G).

TQ=f(ps, ΔP) (
10) On the other hand, from the Proer characteristic, the relationship of equation (U) always holds O TQ' = Mu・ΔP' + B
(ll) here "t' A, B!; j 7' o
This is a unique value.

In addition, when operating a sintering machine, 'I'Q-TQI, ΔP = ΔP
' is established, and by solving the simultaneous equations of equations (10) and (11), it is possible to calculate an arbitrary pallet speed (negative pressure (6) (ΔP) at PSI) and wind IN (TQ).

Figure 1 of the attached drawings is a graph showing an example of the relationship between the pallet speed and the suction air volume determined by the method explained above. When a certain target air volume is indicated, it shows the pallet that can achieve that air volume. The speed can be determined from the graph in FIG.

Similarly, when changing the layer thickness (H) in order to reach a given target air volume, use the graph in FIG. The layer thickness corresponding to the landscape can be determined.

Figure 8 shows the change over time in the total suction air volume when the pallet speed is changed according to the present invention. According to the drawing, the target air volume is reached within 80 minutes after the operation. 0Similarly, Figure 4 shows the change over time in the total suction air volume when the layer thickness changing operation based on the present invention is performed, but in this case as well, within 80 minutes. It is clear that the pallet speed and layer thickness changing operation based on the present invention has extremely high prediction accuracy. Figure 5 also shows that the pallet speed changing operation based on the conventional method is highly accurate. It shows the change over time in the total suction air volume when the operation is performed. In the drawing, it takes more than 60 minutes to reach the target air volume. For these reasons, according to the method of the present invention, it is possible to quickly respond to air volume fluctuations,
The effect of contributing to quality stabilization is extremely significant.

[Brief explanation of the drawing]

Figure 1 shows the pallet substrate m/wi obtained by the method of the present invention.
Figure 2 is a graph showing an example of the relationship between layer thickness and air volume, Figure 8 is a graph showing an example of the relationship between layer thickness and air volume, and Figure 8 is changed to the pallet speed calculated according to the present invention. Figure 4 is a graph showing the change in total suction air volume over time when the calculated bed height is changed according to the present invention. Figure 6 is a graph showing the change in the total suction air volume over time when This is a drawing showing the change in total suction air volume over time when three pallet speed changing operations are performed using the method. Remains (””%uLN)'1M

Claims (1)

[Claims] 1. Installed in the wind box part of a Dwight Lloyd sintering machine or at four or more locations on the top surface of the sintering machine. Input the wind speed measurement value obtained from the anemometer, pallet speed, layer thickness, and suction negative pressure into the sintering model and calculate it to find the target air volume, and operate the optimal pallet speed or layer thickness to reach the target air volume. [Characteristics] Method for determining the optimum operating amount for operating conditions in sintering machine operation.