JPS6067604A - Measurement of interior condition of blast furnace - Google Patents

Abstract

PURPOSE:To make possible accurate measuring of the conditions in blast furnace by inserting fixed sondes and consumable type vertical sondes which provides gas sampling holes and thermocouples into plurality of places in radial directions of charged raw materials at the top part of the blast furnace. CONSTITUTION:Measuring apparatus comprising fixed sondes 1 and consumable vertical sondes 4 to which furnace gas sampling holes and thermocouples are provided, and disposed at the plurality of places in radical direction at stock line 12 of charged raw materials (m) positioned below the large bell (b) at the top of the furnace (a). The temp. and the gas composition in the furnace is measured using fixed sondes 1 at the each part of the upper part of the raw materials charged for monitoring changes of temp. distribution and the condition proceeding in the furnace. With the fixed sondes 1, the positional deviation of softened- melt deposit zone of raw materials, vertical temp. distribution, and gas composition in the furnace are measured, if any changes or disorder of operation of furnace may have occurred, the vertical sonde is used by lowering it using detecting weight attached thereunder, referring these data to the result on the condition in the furnace estimated from the fixed sonde 1, from which the condition in the furnace in known accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for accurately measuring the internal condition of a blast furnace.

(Prior art and its problems) There are two general methods for measuring the internal conditions of blast furnaces that are currently employed: (1) a horizontal sonde method and (2) a vertical sonde method.

The former method using a horizontal sonde involves pushing a water-cooled sonde horizontally into the furnace from the side wall of the upper stage of the blast furnace shaft, and inserting the sonde into the furnace as needed (2 to 3 times/day). There are two methods: one in which the situation inside the furnace is measured using a sensor, and the other in which a sonde is permanently installed inside the furnace to constantly measure the situation inside the furnace.

However, the former (Method ■) measures less frequently, so the collected data is not representative, and the latter (Method O) has representative measurement data, but there is a cantilever inside the furnace. Since the sonde is installed in the same state, there are problems such as the equipment life of the sonde is short and maintainability is poor. Furthermore, in both cases, since the sonde is installed horizontally, the load of the charge acts from above7, and in order to have the strength to withstand this, the sonde must be large and have a water-cooled structure. Therefore, there are problems such as the measured temperature data becoming low due to the influence of this sonde cooling, and furthermore, since such a horizontal sonde can only collect data near the stock line in the furnace, The situation could only be estimated by model simulation, and there were problems such as the inability to accurately know the progress of the reaction in the height direction inside the reactor.

In order to compensate for these drawbacks, the latter method using a vertical sonde was proposed. That is, a sonde having a high melting point metal tube with a built-in thermocouple and a weight made of a high melting point metal attached to the tip of the metal tube and provided with a plurality of through holes and a temperature measuring part of the thermocouple. is charged from the top of the furnace, a weight is placed in the furnace, and as the charge is unloaded, the sonde is sequentially retracted into the furnace, and the temperature in the height direction in the furnace, the gas composition,
This is a method of measuring pressure distribution, etc. (Special Public Interest Publication 1977-43
No. 721, JP-A-55-73807, JP-A-49-1
(Refer to No. 23407) However, this method using a vertical 1α sonde is also durable up to temperatures of about 1350°C, at which ores etc. soften and fuse.

(Unexamined Japanese Patent Publication No. 49-123407), and since the sonde is quite flexible, it is difficult to know where Raina 11 will go after entering the reactor. Therefore, in order to solve the above problem, the present applicant applied a certain tension to a flexible sonde and moved it into the furnace.
The method was disclosed in JP-A-57-1524+15. This enabled the flexible sonde to be sent vertically into the furnace at the top of the shaft, but since this sonde is a consumable type, it is not possible to take frequent measurements, and therefore it is difficult to elucidate the phenomena inside the furnace. (Although C is effective, it has the inherent problem that it cannot be used effectively for furnace condition management.

(Objective of the Invention) The present invention solves the drawbacks of the furnace (1 situation measurement method) using horizontal sondes, vertical 11'I sondes, and expendable vertical sondes as described above, and provides reliable 4R measurement data. The purpose of this study is to provide a method for measuring conditions inside a blast furnace that can capture accurate data that can be used for furnace condition control.

(Structure of the Invention) The present invention comprises a fixed sonde provided with a gas sampling hole and a thermocouple at its tip, a flexible high melting point metal tube with a built-in thermocouple, and a plurality of tubes attached to the tip of the metal tube and arranged around its outer periphery. Using a consumable vertical sonde equipped with a detection weight consisting of a through hole and a temperature measuring part of the thermocouple, the fixed sonde was placed at multiple points in the radial direction in the direction of charging at the top of the bed, perpendicularly from above the stock line. The temperature and gas composition inside the furnace are normally measured using this fixed sonde, and when the operation is changed or the furnace condition is poor, the above-mentioned expendable vertical sonde, which is located at the same radial position as the above-mentioned fixed sonde, is used to unload the charge. This is a method of measuring the internal conditions of a blast furnace, in which the temperature, gas composition, and pressure distribution in the height direction of the furnace are measured by building and feeding it downward, and the cause of changes in the furnace conditions is determined.

(Example) The present invention will be described below based on an example shown in the accompanying drawings.

In the drawing, (1) is a fixed sonde, and the fixed sonde (1) has a ceramic sprayed surface, for example, to withstand wear during installation in the furnace, and has a gas sampling hole (2) and a temperature measurement hole at its tip. For example, it is of a known structure in which a sheathed thermocouple (3) is installed. Also (4
) consists of a flexible high melting point metal tube (5) and the metal tube (
It is a consumable vertical sonde having a detection weight (6) attached to the tip of the high melting point metal tube (51), and a thermocouple (7) is installed inside the high melting point metal tube (51). Designed to allow gas to pass through.

The detection weight (6) is made of a high melting point metal like the metal tube (5), and is provided with a plurality of through holes (8) on its outer periphery, and has the thermocouple ( 7) The temperature measuring unit is buried.

(9) The above-mentioned consumable vertical sonde (4) is connected to the blast furnace charge (1).
n) Sonde drive fj for lowering in response to unloading
The sonde drive mechanism (9) has a correction μm
The vertical sonde (4) fed out from the sonde drum αυ passes through the feeding length measuring device [1, straightening roller αO] and bends. After the vertical sonde is straightened, it is lowered to a fixed position in the radial direction on the stock line (121) in the furnace, and as the blast furnace charge (m) is unloaded, the vertical sonde is This is a well-known structure in which a constant tension is applied by a braking device built into the sonde drum αυ, and the sonde drum αυ is sequentially fed into the furnace.

(13) is a guide tube for guiding the fixed sonde (1) and the consumable vertical sonde (4) to a predetermined position in the radial direction inside the entire blast furnace (a), and the guide tube 03) is the one in this embodiment. In some cases, two probes, one for a fixed probe and one for a expendable vertical probe, are shown stacked in two layers, one above the other. It is.

In addition, in this embodiment, the guide tubes (13 are four guide tubes α (to) in the core and intermediate portions, which are longer in length, are bundled together to increase rigidity, and the guide tubes u3) are Reinforce it by hanging it from the side with a tension rod αa,
In addition, the guide tube qj portion, which is in contact with the material falling from the large bell (b), is made of wear-resistant material (tS) such as SKD steel or SKS steel.
For example, the guide tube (13) is covered with a screen to prevent wear and tear.

Furthermore, in this example, the fixed sonde (1) and the expendable vertical sonde (4) were installed at three points in the radial direction of the blast furnace (υ), that is, at the wall side, the middle part, and the core part. However, it is limited to this, and it goes without saying that multiple points may be installed, and in this embodiment, the top sondes of the reactor core, intermediate section, and reactor wall are each installed separately. insertion slot (
d) to be installed in the furnace, but the insertion opening (Φ
Depending on its size, it may be inserted into the furnace from one place.

aOke Gas sampling hole (2) of the above fixed sonde (1)
) connected to a sampling gas tube (Iη) and a gas pressure measuring device connected to each proximal end of the refractory metal tube (5) of the consumable vertical sonde (4), Connected gas analyzer, θ9 is each thermocouple 1.u)(
This is a temperature recorder connected to 11.

In addition, (e) in the figure is a gas cutoff valve attached to the outlet end of the insertion port (d) provided in the furnace wall of the blast furnace (a), (e) is also a sonde cutter, and (f) is a gas cutoff valve ( This is the loading part for the detection weight (6) interposed between the sensor (c) and the sonde cutter (e).

Next, a method of the present invention will be described in which the conditions inside the furnace are measured using a bed top sonde consisting of the above-described fixed sonde (1), expendable vertical sonde (4), and the like.

In the charge (m) at the top of the bed of the blast furnace (a),
Multiple points (in this example, three points) are fixed in the radial direction.
). To install this fixed sonde (1), after reducing the stock line (121) to a position below the installation tip position of the fixed sonde (1) when the blast furnace is shut down, the fixed sonde (1) is inserted into the furnace through the guide pipe (13). Once inserted, the fixed sonde (1) becomes vertical due to its own weight 9, and then, when the raw material is loaded into the furnace, the fixed sonde (1) is captured and installed in the charge.

Fixed sonde installed at multiple points in the radial direction (1)
During operation, the temperature and gas composition inside the furnace are constantly measured at the top of the charge (m) to monitor changes in the temperature distribution within the furnace and the progress of the reaction. In addition, the height of the softened cohesive zone of iron ore in the furnace at that radial position is also estimated using a simulation model. In addition, during normal operation, the level of the charging material is maintained within the range of the predetermined stock line position, so the tip of the fixed sonde (1)
', it never appears on the surface of the rough stone.

If the estimated position of the softened cohesive zone by the above fixed sonde (1) deviates from the pre-planned range, or when there is a change in operation or when the reactor condition is poor, the position in the same radial direction as the above fixed sonde (1) The expendable vertical probe (4) is taken out and the temperature and gas composition distribution in the height direction inside the furnace are measured to confirm the effects of the operating changes and the cause of the furnace condition.

Then, the b1 measurement data obtained by the expendable vertical sonde (4) is compared with the results of estimating the reactor situation by the fixed sonde (1), and if the two do not match, the fixed sonde (1) is used.
The heat exchange coefficient and reaction rate constant between the gas in the furnace and the charge (m) in the furnace condition estimation model using the measured data were measured using an expendable vertical sonde (4). Fix it.

(Specific Example) Figure M3 shows the results of two measurements of furnace temperature, CO2, Co, and furnace pressure using the I-layer top sonde according to the present invention. 109 in the figure. ○101, (G is the temperature inside the furnace, ...Δ..., -Mu is CO7, ...
Mouth..., -a-1dCOf-%mata...0 songs, -
a- represents the pressure inside the furnace, and the solid line represents the first time,
This marks the second time the company has collapsed.

As is clear from Fig. 3, the air flow conditions (air flow rate, air temperature, air pressure, air humidity, liquid ratio) and original F4 conditions (moisture in coke, sintering ratio, etc.) were almost the same over two days. The reproducibility of the measurements is very good, and measurements can be made with sufficient accuracy.
I understand that.

(Effects of the Invention) As described above, according to the present invention, it is possible to measure the furnace temperature, furnace gas pressure, furnace gas composition, etc. more accurately than by conventional fixed sondes, and to control the furnace condition. It has a great effect on

[Brief explanation of the drawings] Fig. 1 is a schematic groove bottom view of the layer top sonde used in the method of the present invention, Fig. 2 is the same (enlarged explanatory view), and Fig. 3 is the furnace temperature measured by the method of the present invention. , Co1, C0, and the furnace pressure. (1) is a fixed sonde, (2) is a gas sampling hole, (
3) is a thermocouple, (4) is a consumable vertical sonde, (5) is a high melting point metal tube, (6) is a detection weight, (7) is a thermocouple, (81
i, i hole, (1; Seed stock line. Patent applicant Sumitomo Metal Industries, Ltd.

Claims (1)

[Claims] (1) A fixed sonde with a gas sampling hole and a thermocouple at its tip, a flexible high-melting point metal tube with a built-in thermocouple, and a plurality of through holes attached to the tip of the metal tube and the thermocouple on its outer periphery. Using a consumable vertical sonde with a detection angle each having a temperature measuring part, the fixed sonde is installed at multiple points in the radial direction within the top charge, vertically from the stock line, and constantly This fixed sonde measures the temperature and gas composition inside the furnace, and when the operation is changed or the furnace condition is poor, the consumable vertical sonde located at the same radial position as the fixed sonde is placed under the load V of the charge. Accordingly, the temperature, gas composition, and pressure distribution in the height direction of the furnace are measured.'f1: Characteristic method for measuring conditions inside the blast furnace.