JPS59185739A - Detection of position of forefront of combustion for sintering arriving at grate - Google Patents

Abstract

PURPOSE:To improve the quality of sintered ore in the stage of producing the sintered ore for a blast furnace by measuring the position of the palllets in a sintering machine and the temp. of grates, estimating the position of the forefront of combustion arriving at the grates and adjusting the same to a correct position. CONSTITUTION:Many pallets 31 provided with grates on the surface are moved like an endless belt by sprockets 4, 4a and a sintering raw material is supplied thereon and is fired by an ignition furnace by which the raw material is sintered under movement. The sintered ore is discharged as sintered ore B from the sprocket 4a side. The speed of the pallets 31, the amt. of the raw material to be supplied and the flow rate of the air to be discharged during sintering are adjusted in a way to bring the position of the forefront of combustion arriving at the grates (FFP) where the front end of a sintering zone C formed in the sintering raw material layer arrives at the base of the pallets 31 to the terminal on the ore discharging side of the pallets, thereby improving the quality of the sintered ore and improving the productivity of the sintered ore. The data from a sensor 22 for measuring the position and a thermometer 24 provided in the lower part of the pallets 31 is calculated in an arithmetic circuit 21 for the above-mentioned purpose to calculate FFP, and the above-mentioned control is performed so that the FFP comes at the terminal on the ore discharging side of the pallet 31.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the position at which a sintering combustion front reaches a grate in a sintering machine for producing sintered ore, which is a raw material for a blast furnace.

As shown schematically in Figure 1, the sintering machine consists of a charging hopper 1 installed at the ore feed end, an ignition furnace 2, and a large number of pallets 31, 31, and 31, each having a grate on its surface. The sintering machine main body 3 which is connected in an annular manner, the frame 41 that supports the pallet 31, the pallet drive sprocket 4 on the ore feeding end side and its drive source, and the forced ventilation from the upper side of the L/t 31 to the lower side It is composed of a large number of wind boxes 5, 5, . . . , and an exhaust pipe 7 that guides the exhaust air from the wind boxes 5, 5, . . . to a blower (not shown). As shown in the schematic cross-sectional view, pallets 31, 31, .
A large number of wind boxes 5, 5, . The raw material is sintered by forced ventilation from the upper side of the pallet to the lower side of the pallet using a blower (not shown) through the exhaust pipe 7, and is discharged as sintered ore B from the ore discharge end. The layered part extending diagonally downward in the direction of movement of the pallet 31 from the ignition furnace is the combustion zone C, and this combustion zone or the pallet 3
The position where the bottom of 1 is reached is the combustion front grate arrival position (F
, F, P,).

The quality of the sintered ore produced in such a sintering machine depends on the blending ratio of the charged raw materials, charging density, sintering time, etc., but from the perspective of production efficiency, the sintering machine itself It is desirable to set the moving speed, ore supply amount, exhaust air volume, etc. of the pallets 31, 31, etc. so that sintering is completed at the end of the ore discharge terminal in No. 3. F, F, 1)
The combustion of raw materials called pallet 31.31
It is necessary to accurately detect the bottom surface of ..., that is, the position where the bottom surface of the charged raw material reaches the contacting crate.

Conventionally, the following methods have been used to detect F, F, and P. Multiple (3 or more) wind boxes 5 or exhaust branch pipes 6 slightly closer to the ore discharge end than the ignition furnace 2 at the ore feed end, and multiple (3 or more) wind boxes 6 at the ore discharge end. The OF, F, and P measure the temperature of the exhaust air using a thermometer installed in the wind box 5 or the exhaust branch pipe 6, and based on this, create a temperature distribution map as shown in Figure 3. In Figure 2, the horizontal axis is the wind box number (
The temperature of raw material A is F, F, Since it is thought that F, F, and P can change significantly with the boundary as the boundary, F, F, and P can be estimated based on the actually measured exhaust air temperature.

As an estimation method, the temperature distribution on the combustion side and non-combustion side is approximated to a straight line or curve, and the intersection points are F, F,
P, but as shown by the dashed line, the combustion side is approximated by a binotic curve y=a+bx+cx2, and the non-combustion side is a straight line y=a with the average value as a constant, and the intersection of the two is F.
, F, P, O In this case, the basic measurement value (!:
,．． 31... Due to uneven permeability of the raw material charged above, leakage of air to the wind boxes 5, 5... It has the disadvantage that it is difficult to measure the true exhaust gas temperature from the raw materials that are currently being used.Furthermore, since ventilation is performed using one blower, it is difficult to measure the temperature of the exhaust gas from a thermometer or each installed air box 5. The exhaust air volume is pallet 31.
31 - The problem is that it depends on the relative permeability of the entire raw material charged above, and therefore it is essentially impossible to estimate the exhaust gas temperature at a specific location from the measurements taken by each thermometer at the same time. There was a point. Therefore, the conventional method of detecting F, F, and P, which has been calculated and estimated using such a method, naturally has low accuracy, and therefore, F, F, and P, which are more accurate, are less accurate.

A detection method was needed.

The present invention has been made in view of the above circumstances, and measures the grate temperature with a thermometer installed on the grate of the pallet, detects the position of the pallet where the thermometer is installed, and measures the grate temperature. The method is characterized in that the measured values and the position detection information of the pallet are stored in time series, and the combustion Ml line arrival position is calculated based on this stored information.

The present invention will be described in detail below with reference to the drawings showing its implementation state.

FIG. 4 is a schematic diagram showing the implementation state of the method of the present invention, FIG. 5 is a partially enlarged plan view of the pallet 31, and FIG. 6 is the v+ −
It is a sectional view taken along the Vl line. A pallet sensor 22 using a micro switch or the like is installed in the upper passage area of the pallet 31 at a position slightly closer to the discharge end of the ignition furnace 2 of the sintering machine, and each pallet passing over this pallet sensor 22 310% foot part, for example, the front end in the traveling direction, is detected, and the signal is sent to the calculation circuit 21. is man-powered. A position slightly closer to the ore discharge end than the pallet sensor 22 and a position near the ore discharge end.
・Procera) 4a There are pillars 42 and 42 erected at positions slightly closer to the ore feed end, and both pillars 42°4
A wire 43 is stretched between the two, and this wire 43
A compensating lead wire 45 for thermocouples supported by a large number of pulleys 44, 44, etc. is installed, and its end on the discharged ore side is connected to the arithmetic circuit 21 via the A/D converter 23. has been done.

The sintering machine main body 3 includes a number of annularly connected barrels) 31,
As shown in FIG.
The longitudinal direction of the barren 31 is taken as the moving direction of the barren 31, and a large number of them are placed side by side in a direction perpendicular to this. ) is formed. Furthermore, as shown in FIG. 6, between the pallets 31.
, 32 in the grooves 32b and 321:l extending parallel to the width direction thereof, and a T-shaped portion formed at the upper end of the frame that is moved by the drive sprocket 4 on the frame 41. 33 are connected by fitting each other, and as the frame moves, the springs) 31. ．． 31...
・The pallet 31 will also be moved on the frame 41.
31... is either a crate thermometer 24 using a thermocouple that measures the temperature of the great par 32 at intervals of 3 or 4, or an adjacent great par 32.3 approximately at the center in the width direction of the pallet 31.
The terminal 2.4 & is the T of the frame.
A compensation conducting wire 45 extends along the character-shaped portion 33 to the side surface of the balent 31 on the installed side. The terminal 24a of the grate thermometer 24 extending from the side surface of the pallet 31 can be attached to and detached from the ore feed end side end of the compensating conductor 45 by means of an appropriate connector.

Similarly, the arithmetic circuit 21 utilizes a microcomputer, and is equipped with a keyboard switch 25 for issuing various commands, a display device 27 for displaying the results of arithmetic operations, and the like.

FIG. 7 is a flowchart showing the process inscription of the arithmetic circuit 21 when implementing the method of the present invention with the above-described configuration.
, the detection method will be explained for each baren) 31.
31... are assigned numbers from 1 to M for identification, and the pallet 31 with the smaller number is located at the front in the traveling direction, that is, the pallet 31 is discharged at the upper circumferential position of 31... It is assumed that the number of the end pallet 31 is small.

When the number n of the pallet 31 on the pallet sensor 22 is input using the keyboard switch 25, the arithmetic circuit 21 stores that number n, and updates the number when the next pallet 31 is detected by the pallet sensor 22. , and also stores the time tn at which the pallet 31 was detected by the pallet sensor 22. Next, select the balent 31 where the grate thermometer 24 is installed, which is located a little closer to the discharge end side than the ignition furnace 2, and select the terminal 2 of the grate thermometer 24.
4a is connected to the end of the compensating conductor 45 on the ore feeding end side to enable the arithmetic circuit 21 to read the measured value of the grate thermometer 24, and then the number N of this pallet 31 is input using the keyboard switch 25. This pallet to be measured 3
When the number N of 1 is input, the arithmetic circuit 21 calculates the number of pallets 31 (nth) on the nodelet sensor 22 at that time and the pallet 31 (n-1) that passed before it.
Time tn and tn detected by the node sensor 22
-1 is memorized, so the latest moving speed V of the pallets 31', 31, etc. at the present moment is calculated by the following formula (1) based on the length l per pallet 317.○v- l
/(tn-tn-0)...(1) However, V
: The latest Noklet movement speed I! : Length per pallet tn : Current pallet detection time tn - □ : Previous pallet detection time Next, the number N of the specified measuring pallet 31 or the pallet 310 number n on the pallet sensor 22 is determined by the dog. If there is, that is, the number N of the measuring node 31 is between the measuring pallet 31 and the pallet sensor 22, then the formula (2) below is used. If the number n of a certain number (let 31) or less is below, the value of the measured pallet 310 from the ignition furnace 2 at the time when the front end of the part (let 31) currently on the pallet sensor 22 is detected by the pallet sensor 22 is determined by the following equation (3). Calculate distance ○ L=a +l (M-N+n) -(2)L
=a+l(n-N)-(3)L2 Distance a from the ignition furnace to the measurement node: Distance M from the ignition furnace to the pallet sensor: When processing for more than the total number of pallets is completed, the calculation circuit 21 determines whether it is possible to read the measured temperature from the great thermometer 24,
If possible, the measured temperature S is read from the grate thermometer 24 at predetermined time intervals, and when the temperature data Si of the grate thermometers 2-4 is read, the temperature Si is determined by the following equation (4). The distance Xi from the ignition furnace 2 to the measured position is calculated.

X, = V (T-tn) + L - = (4), X.: Distance from the ignition furnace to the temperature measurement position T: Time at which the temperature is measured tn: Pallet or pallet above the Hallett sensor Time detected by the sensor T-tn: Time from the latest pallet detection time to temperature measurement In this way, the distance from the ignition furnace 2 to the temperature measurement position
When i is calculated, the arithmetic circuit 21 stores it together with the measured temperature Si at that position, and stores it in the pallet sensor 22 as the next n +
The measured temperature value from the grate thermometer is measured at predetermined time intervals until the No. 1 pallet 31 is detected or the terminal 24a of the grate thermometer 24 is disconnected from the compensation conductor 45 and temperature reading becomes impossible. The storage of S1 and the measurement calculation and storage of the distance Xi of the measurement position from the ignition furnace 2 are repeated. Then, the pallet sensor 22 detects arrow n + 1
When the passage of the number 31 pallet is detected, the arithmetic circuit 21
After updating the number of the pallet 31 on the pallet sensor 22, the same process as described above is carried out.

While the measuring pallet 31 moves to the ore discharge end in this manner, the grate temperature Si is measured and its measurement positions X and i are calculated, and these data are sequentially stored and file-linked. When the measuring pallet 31 reaches the vicinity of the discharged ore end, the terminal 24a of the grate thermometer 24 is connected to the compensating conductor 45.
Then, the arithmetic circuit 21 determines that it is no longer possible to read the measured temperature s1 from the grate thermometer 24, and reads the filed grate temperature Si and the information from the ignition furnace 2 at the position where it has been measured. Distance data with summer (5ijx+
).

(S2.x2 houses...F, F, P as follows based on (Si, Xi).

Calculate.

First measured temperature value St & other measured temperature values s2゜S3
...Respective differences d,, d2...d, (j
= i-1) and calculate the coefficients a, b, and C of each term of the quadratic regression formula from the data of each measured temperature value S1 and its measurement position Xi, which are smaller than this djQ value or a predetermined value. Calculate, then a, O value or D
Calculate the average value of each of the 8 smaller measured temperature values,
Calculate the solution X by substituting it into the quadratic regression equation, and convert it into F
. In the detection method, the grate temperature is measured with a thermometer installed on the grate of the pallet, the position of the pallet on which the thermometer is installed is detected, and the grate temperature measurement value and the position detection information of the pallet are recorded in chronological order. Since the combustion front arrival position is calculated based on this stored information, it is possible to detect the combustion front arrival position much more accurately than conventional methods. Therefore, the productivity of the sintering machine and the quality of the sintered ore produced by the sintering machine are improved.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a sintering machine to which the present invention is applied, Fig. 2 is a schematic cross-sectional view of the sintering process, Fig. 3 is an explanatory diagram of a conventional combustion front arrival position detection method, and Fig. 4 5 is a partially enlarged plan view illustrating how to install the gray thermometer, FIG. 6 is a sectional view taken along the Vl-Vl line, and FIG. 7 is a calculation circuit. 0 3...Sintering machine main body 21...Arithmetic circuit 22...
Pallet sensor 24...Grate thermometer 31...
・Barre ・t 32...Great Bar Patent Applicant Sumitomo Metal Industries Co., Ltd. Agent Patent Attorney Noboru Kono 2 Figure 1 Human shellfish! Subordinate number

Claims (1)

[Claims] 1. In a method for detecting the position where the sintering combustion front of a sintering machine reaches the grate of a pallet, the grate temperature is measured with a thermometer installed on the grate of the pallet; Sintering combustion characterized in that the position of the installed pallet is detected, the grate temperature measurement value and the pallet position detection information are stored in chronological order, and the combustion front arrival position is calculated based on this stored information. Front Great Arrival Position Detection Method.