JPS60262926A - Method for controlling concentration of component in product sintered ore - Google Patents

Abstract

PURPOSE:To measure the concn. of components in product sintered ore at an early stage with high precision and to stabilize the blast furnace operation by introducing laser emission spectrometry. CONSTITUTION:A laser emission spectrometer 1 is provided on a Dwight-Lloyd sintering machine, and a laser beam is irradiated on the point A on the surface of a sintered layer 3 through a nozzle 2 to emit light by excitation. The light is analyzed with emission spectrometry, and the concn. of the components at the point A on the surface is measured by a calculator 5. The concn. of components is corrected on the basis of a relation between the concn. of components of the surface layer part of the sintered layer 3 which is already inputted to the calculator 5 and the concn. of components of the product sintered ore, and the concn. of components of the product sintered ore is estimated. The value is fed back to an auxiliary material system, and the quarrying of auxiliary materials such as limestone and serpentinite is regulated on the basis of said information. The concn. of components of product sintered ore such as T.Fe, CaO, and SiO2 is thus controlled to obtain the desired value.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention belongs to the field of operating technology for a Dwight Lloyd sintering machine, and in particular, the technical content described in this specification regarding a method for controlling the component concentration of finished sintered ore is based on laser emission spectroscopy. This paper proposes a technology that makes it possible to minimize variations in the concentration of components in finished sintered ore, which can have a negative impact on blast furnace conditions, by optimizing the use of equipment to suit sintering operations. It is.

Background technology Sintered ore is mainly composed of iron oxides (Fe20B, Fe, O,, F
eO) and CaO, Sin, , A4,08, MgO
The concentration of these components varies depending on the ratio of sintered ore used in the blast furnace, but in general,
~6? wt%, CaO; 8~l 0wt%, 5t
o2; 5~? wt%, All, 08; 1.7-2
．． 5 wt%, MgO; approximately 1.5 to L5vt%. Fluctuations in the concentration of sintered ore components can lead to errors in material/energy balance calculations in the blast furnace, resulting in fluctuations in the amount of iron tapped, top gas recovery amount, fuel ratio, etc. Control is extremely important.

Conventional technology and its problems Conventionally, the concentration of components in finished sintered ore is at the exit from the sintering factory.
Samples of sintered ore that have been pulled are crushed and measured using fluorescent X-ray analysis, and it takes 4 to 6 hours after the raw material is cut out for the operator to obtain the analytical values for the component concentrations. Therefore, it goes without saying that it is impossible to suppress component fluctuations due to this time delay, and even controls (usually, cutting limestone and serpentine) that sometimes promote component fluctuations due to this time delay. There were times when I would do that.

Purpose of the Invention The purpose of the present invention is to overcome the drawback of the prior art that the feedback of the analysis value of the component concentration of finished sintered ore to the operational system is delayed, and by introducing a laser emission spectrometry method. The component concentration of the finished sintered ore is estimated from the measured value of the surface layer of the sintered layer during operation, and the time required for the operator to obtain the analytical value has been shortened from the conventional 4 to 10 seconds to within 80 minutes. In this paper, we propose a control technology that can improve the controllability of component concentrations in finished sintered ore.

Structure of the Invention The feature of the present invention is that a laser emission spectrometer is installed on the Dwight Lloyd sintering machine to irradiate the surface of the sintered layer with laser light, and to analyze the excited emission produced by the irradiation using emission spectroscopy. , the component concentration in the surface layer of the sintered layer is measured, and this measured value is corrected based on the relationship between the component concentration in the surface layer of the sintered layer and the component concentration in the finished sintered ore to determine the component concentration in the finished sintered ore. This estimated value can be summarized as a configuration of 5K points that is fed back to the cutting control of auxiliary raw materials such as limestone and serpentine.

FIG. 1 shows the implementation state of the present invention. First, the procedure for analyzing the component concentration of the surface layer of the sintered layer during operation, which is performed prior to controlling the component concentration, will be explained. First, the laser beam irradiated from the laser generating part located inside the laser emission spectrometer IK passes through the nozzle B and hits point A on the surface layer of the first sintered layer 8. The condensed energy of the laser beam causes the surface of the sintered layer to The part evaporates to create microplasma, which is excited and emits light.

This light is received by a light receiving section in the device 1 through a nozzle 8 and introduced into a spectrometer, and the components and their concentrations are measured from the wavelength and intensity of the spectral lines unique to each component. Note that the line spectrum is exchanged into a current signal or a digital signal and guided to the computer 6 based on the cable number, and this computer converts the light intensity into component concentration according to a calibration curve prepared in advance.

In general, there is some component segregation in the sintered layer in the height and thickness direction (sintered layer 8/combustion layer 6/raw material layer?), and in reality, the analytical values and components in the surface layer of the sintered layer As shown in FIG. 3 (shown in the CaoQ example), there is a slight deviation from the analytical value of sintered ore. Therefore, by inputting these relationships into the calculator 5 in advance, the component concentration of the entire finished sintered ore is shown in Figure 8 from the analysis values at the surface layer of the already sintered layer (sio
, as typified by the example of 1), it becomes possible to estimate with high accuracy.

When installing the laser emission spectrometer on the sintering machine, the vibration of the sintering factory building was a major cause of noise generation in the laser emission analysis, but this was alleviated by using a vibration-proof structure for the main body. I was able to solve it. The installed laser emission spectrometer has a light energy of 1 joule, a laser wavelength of 1.06 microns, and a pulse width of B? sec.

In addition, in the conventional analysis method, sampling errors due to the segregation of raw material components in the longitudinal direction of the sintering machine were a big problem, but according to the method of the present invention, a large number of analytical values (SO The average value of 60 or more samples per minute can be calculated instantly using a computer, which greatly improves the representativeness of the analytical values.

Next, as described above, the component concentration value of the finished sintered ore can be obtained from the component III degree of the surface layer of the sintered layer during operation. Feedback to charging system. In other words, based on this feedback information, the amount of auxiliary raw materials such as limestone and serpentine is adjusted to achieve the target T, Fe 5CaOSSin.
The concentration of the components of the finished sintered ore is controlled to be the same as that of Cape G.

Note that the position of the laser emission spectrometer is preferably closer to the ignition furnace from the viewpoint of improving the accuracy of component control, and more preferably at multiple locations across the width of the pallet.

Examples A case in which laser emission spectrometry was adopted to control the operation of a sintering machine (operation example of the present invention) and a case in which it was not controlled (5
Conventional operation example) and K, CaO in sintered ore and 810. The standard deviation of the concentration is shown in Table IK.

As can be seen from this table, the variation in concentration was smaller in 5K CaO5Sin and 4)K in the operation example according to the method of the present invention, confirming the effectiveness of the method for controlling the concentration of sintered ore components according to the present invention. In this example, the laser emission spectrometer was installed at a position 6 m from the ignition furnace to the ore discharge side.

Table 1 Variations in Cab and Sin during each operation period Effects of the invention As is clear from the above description, according to the present invention, the concentration of components in finished sintered ore can be measured early and with high accuracy. Fluctuations in the concentration of components in the concretion can be suppressed, helping to ensure stable blast furnace operation.

Furthermore, when focusing on the method of analyzing product concentration, sampling errors due to the segregation of raw material components in the longitudinal direction of the sintering machine were a major problem in conventional analysis methods, but according to the method of the present invention, it is possible to Since the average value of a large number of analytical values (60 or more possible in 80 minutes) obtained can be calculated instantly by computer, the representativeness of the analytical values can be greatly improved.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the implementation state of the present invention method in which a laser emission spectrometer is installed on the sintering machine, and Figure 2 is an illustration of the analytical value of CaO in the finished sintered ore and the results of sintering by laser emission spectrometry. Figure 8 is a graph showing the relationship between the CaO analysis value in the layer surface layer and the 810. 1 is a graph showing the relationship between the analytical value of and the concentration of Sin in finished sintered ore estimated by laser emission spectrometry. 1... Laser emission spectrometer 2... Nozzle B... Sintered layer 4... Cable 6... Computer 6... Combustion layer? ...Raw material layer. Figure 1

Claims (1)

[Claims] 1 A laser emission spectrometer is installed on the Dwight Lloyd sintering machine, and the surface of the sintered layer is irradiated with laser light, and the excited emission produced by the irradiation is analyzed by emission spectroscopy to determine the components of the surface layer of the sintered layer. The concentration is measured, and this measured value is corrected based on the relationship between the component concentration in the surface part of the sintered layer and the component concentration in the finished sintered ore, and the component concentration in the finished sintered ore is estimated. A method for controlling the concentration of sintered ore components in a finished product, characterized by feeding back to control of cutting out auxiliary raw materials such as limestone and serpentine.