JPH03240926A - Method for estimating distribution of carbon concentration in height direction of sintered layer - Google Patents

Abstract

PURPOSE:To exactly detect the distribution of the carbon concn. in the height direction of a sintered layer in a short period of time by inputting the respective measurement signals of the carbon concn. measuring instruments, gas flow meters and gas thermometers mounted to respective window boxes to a computing machine and making prescribed computations. CONSTITUTION:The measurement signals of the respective flow meters mounted to the respective window boxes(WB) of a DL type sintering machine are sent to a computing section 22 for the distribution of the gas flow rate in the longitudinal direction of the computing machine 20. The measurement signals necessary for determining the position and thickness of the rod hot layer in the longitudinal direction of the machine of the respective gas thermometers, etc., are sent to a computing section 21 for the position and thickness of the red hot layer in the longitudinal direction of the machine. The measurement signals of the respective CO and CO2 concn. measuring instruments and the results (signals) of the computations of a computing section 22 are sent to a computing section 23 which computes the distribution of the carbon concn. in the respective positions in the longitudinal direction of the machine by prescribed equation. The results (signals) of computation of the section 23 are sent together with the results of computation of the section 21 to a computing section 24 where the carbon concn. in the height direction of the sintered layer is computed by prescribed equation. The results of the computation are displayed on a CRT display 25. The distribution of the carbon concn. in the height direction of the sintered layer is controlled in real time in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for estimating carbon concentration distribution in the height direction of a sintered layer.

[Prior Art] In a DL type sintering machine, the concentration distribution of carbon, which is a fuel, in the height direction of the sintered layer has a close relationship with yield, productivity, and quality. That is, if carbon is uniformly distributed in the height direction of the sintered layer, the upper layer will be underheated and the lower layer will be overheated due to the characteristics of the process. Therefore, the yield and strength of the upper layer decrease. For this reason, various charging methods have been proposed in which the carbon concentration is varied in the height direction (segregating the carbon concentration) so that the amount of heat is uniform in the height direction of the sintered layer (for example, Japanese Patent Laid-Open No. 58217642 Publication No.)
.

However, in order to quantitatively understand the carbon concentration in the height direction of the sintered layer, it is necessary to stop the sintering machine, divide the sintered raw material layer in the height direction before ignition, sample it, and chemically analyze the sampled raw material. I had to ask by doing.

[Problem to be solved by the invention] However, the method of determining the carbon concentration distribution in the height direction of the sintered layer requires stopping the sintering machine, sampling, and waiting for the chemical analysis results. There were problems in that it took a long time to find out, and since the measurement frequency was batch-like, it could not be used to control the charging of sintering raw materials.

[Means for Solving the Problems] This invention aims to solve the above problems.
In addition to measuring the CO and CO□ gas concentration and exhaust gas flow rate distribution in the longitudinal direction of each wind box of the sintering machine, the position and thickness of the red-hot layer are calculated from the exhaust gas temperature of each wind box, and sintering is performed based on these results. This is a method for estimating carbon concentration distribution in the height direction of a sintered layer, which is characterized by determining the carbon concentration distribution in the layer height direction.

[Operation: The height of the sintered layer can be determined by inputting the measurement signals of the CO and CO2 gas concentration measuring devices, gas flow meters, and gas thermometers attached to each wind box to a computer and performing the specified calculations. The directional carbon concentration distribution can be detected quickly and accurately.

[Example] Examples of the present invention will be described in detail below. FIG. 2 is a diagram showing the sintering apparatus. 1 is a DL type sintering machine, 2 is a surge hopper that relays the sintering raw material, 3 is a roll feeder that cuts out the sintering raw material from the surge hopper 2, and 4 is a roll feeder that feeds the sintering raw material cut out by the roll feeder 3 to the sintering machine 1. A charging station 5 is an ignition furnace. The sintering raw material is charged from the surge hopper 2 to the pallet (not shown) disposed in an endless manner in the sintering machine 1 via the roll feeder 3 and the charging chute 4, and is transferred to the ore discharge section 10 along with the moving pallet. move towards. The #l sintering material layer (or sintered layer) 6 is ignited on its upper surface in an ignition furnace 5 . On the other hand, the atmosphere is sintered layer 6 (#
The ignited sintered layer is sucked into the main blower via the wind box 7, the branch pipe 8 and the main duct 9. The red-hot layer 11, which is burning and melting at a temperature of 800 to 1,300°C, formed within the sintered layer by the combustion of the coke powder, causes the atmosphere to be sucked downward through the sintered layer 6. As the pallet moves, it descends, and the lower surface of the red-hot layer 11 reaches the lower surface of the sintered layer 6 at a position before the ore discharge section 10, thereby completing the sintering of the entire height of the sintered layer 6. , the sintered layer is discharged in the ore discharge section 10.

The red-hot layer 11 extends from the upper surface of the sintered layer 6 immediately below the ignition furnace 5 toward the lower surface of the sintered layer 6 downstream thereof.

In order to implement the method of the invention, the following measuring equipment is provided at a predetermined location. That is, ■CO, C02
Concentration measuring device; branch pipe 8 connecting each wind box 7 or each wind box 7 and main duct 9; ■Gas flow meter; branch pipe 8 connecting each wind box 7 and main duct 9; ■Gas thermometer; each A branch pipe 8 connecting the wind box 7 and the main duct 9. In addition, if necessary, ■Monitor camera; ore discharge section 10; ■Ultrasonic anemometer: #I above the condensation layer 6 6 Next, the present invention An embodiment of the method is illustrated in FIG.

The measurement signals of each flowmeter are sent to the longitudinal gas flow rate distribution calculating section 22 of the computer 20, while the measurement signals necessary for determining the position and thickness of the red-hot layer in the longitudinal direction of each gas thermometer, etc. The information is sent to the position and thickness calculation unit 21 of the red-hot layer in the longitudinal direction. The measurement signals of each CO1CO2 concentration measuring device and the calculation results (signals) of the calculation section 22 are sent to the calculation section 23.

Here, the carbon concentration distribution Qc(x) at each position in the machine length direction is calculated using the following equation (11).

Qc(xXkg/rd> = (12/2,
240 ) Height of sintered layer (■) 1 - (Carr 1 degree (kg/nf) in lime, quicklime, iron ore that does not contribute to combustion)... (1) The calculation result (signal) of the calculation unit 23 is calculated It is sent to the calculation section 24 together with the calculation result of the section 21, and the carbon concentration Pc(y) in the height direction of the sintered layer is calculated using the following equation (2).

P c (y) (kg/rd) = Qc (x)
X Height of sintered layer (■)/Thickness of red-hot layer (division)... ■ The calculated result is displayed on the CRT display 25.

Note that the gas flow rate distribution in the longitudinal direction is determined using one of the methods shown below.

(1) Method of determining using a pitot tube installed in each wind box.

(Method of measuring wind speed using an ultrasonic anemometer, etc. on the 21#I layer.

(3) As in Japanese Patent Publication No. 59-20736, it can be calculated from the position and thickness of the red-hot layer in the longitudinal direction, the exhaust gas flow rate of the main duct, and the ventilation resistance of each zone of the sintered layer (sintered zone, red zone, etc.). How to ask.

The position and thickness of the glowing layer in the longitudinal direction are also determined using one of the methods shown below.

(1) JP-A-59-66685 and JP-A-61
A method of calculating from the exhaust gas temperature of each wind box and the thickness of the ember layer in the ore discharge area, as in Publication No. 26732.

■A method of calculating from the exhaust gas temperature of each wind box and the exhaust gas flow rate distribution in the longitudinal direction, as in Japanese Patent Publication No. 59-20736.

Figure 3 is a graph showing the results of determining the carbon concentration distribution in the height direction of the sintered layer using the method of the present invention, when the charging chute angle was set to 50 degrees and 55 degrees. It shows. This result confirms the conventional knowledge that the carbon concentration in the upper and lower layers of the sintered layer changes by changing the charging angle.

[Effects of the Invention] Since the present invention is configured as described above, it is possible to continuously estimate the carbon concentration distribution in the height direction of the sintered layer while the sintering machine is operating, and to perform installation in real time. This has the effect that input control can be performed.

[Brief explanation of drawings]

Fig. 1 is a block diagram of carbon concentration calculation in the height direction of the sintered layer using the method of the present invention, Fig. 2 is a diagram showing the sintering equipment, and Fig. 3 is a carbon concentration calculation block diagram in the height direction of the sintered layer using the method of the present invention. FIG. 2 is a graph diagram showing the results of determining the carbon concentration distribution of the carbon concentration distribution. 21... Red-hot layer position and thickness calculation unit in the longitudinal direction;
22... Length direction exhaust gas flow rate distribution calculation section, 23...
Carbon concentration distribution calculation section in machine length direction, 24... Carbon concentration distribution calculation section in sintered layer height direction, 25... CRT
Desbrais Figure 2

Claims (1)

[Claims] In addition to measuring the CO and CO_2 gas concentrations in each wind box of the sintering machine and the exhaust gas flow rate distribution in the machine length direction, the position and thickness of the red-hot layer are calculated from the exhaust gas temperature of each wind box, and from these results, the sintering A method for estimating carbon concentration distribution in the height direction of a sintered layer, characterized by determining a carbon concentration distribution in the height direction of the layer.