JPS5818591B2 - Surface layer position measuring device for vertical furnace contents - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for measuring the surface layer position of a charge material charged into a vertical furnace.

In a vertical furnace, such as a blast furnace, ores and coke are alternately charged, and iron oxides are reduced by high-temperature reducing gas rising from below.

The produced iron and slag are respectively melted and dripped onto the bottom of the furnace.
It is taken out of the furnace intermittently or continuously.

Therefore, the charged ores, etc. (hereinafter sometimes simply referred to as the charge) gradually descend, and new charges are charged in accordance with the descent.

Therefore, knowing the current position of the surface layer of the charge is extremely important in order to know when to add the charge, but even more important is the position of the surface layer in the furnace. It is important to understand the shape of the surface layer.

In other words, according to recent blast furnace dismantling surveys, a remarkable correlation has been recognized between the layer thickness or layer shape of the ore and coke and the furnace operating conditions, and the gas flow conditions and the shape of the softened cohesive zone have been found to be significant. It is known that it has a great influence on

On the other hand, a movable collision plate called an armor plate is placed in the upper part of the blast furnace, and the technology for controlling the stacking state of the charges falling from the lower bell is widely used.

However, the relationship between the operation of the armor plate and the charge stacking situation is only known through model experiments, and there are many unknowns about the correlation under actual reactor operation.

For this reason, it has become necessary to specifically and accurately understand the stacking and distribution conditions of the charges in the furnace, and methods such as those shown in FIGS. 1 and 2 have been proposed.

These are cross-sectional views conceptually showing the structure of the top of the blast furnace.The inner surface of the steel shell 1 is lined with a refractory material 2, and the charge falling from the lower bell 3 forms a raw material layer 4. .

The armor plate 8, which adjusts the falling position of the charge, moves in the left-right direction in the drawing, and when it approaches the core, the surface of the raw material layer 4 becomes highly laminated in the center, and when it moves away from the core,
A low stacked state in the center is obtained.

First, in FIG. 1, a wire guide cylinder 5 is fixed vertically to the top of the furnace, and a weight 7 is attached to the tip of a wire 6 that is inserted into the cylinder so as to be able to rise and fall freely.

The upper end of the wire 6 is then wound around a suitable drum,
In addition, back tension is applied which is slightly stronger than the weight of the wire 6 alone but weaker than the total power of the wire 6 and the weight 7, so when the weight 7 lands on the raw material layer 4, the wire 6 The feeding of the wire 6 is stopped, and the wire 6 does not become slack.

When the raw material layer 4 begins to gradually descend as the reduction reaction progresses, the weight 7 follows it due to its own weight,
It descends while maintaining a situation in which the wire 6 does not become slack.

Therefore, if this follow-up speed or follow-up descent amount is detected based on the circumferential rotational speed, rotation angle, etc. of the drum, the descending state of the raw material layer 4 can be grasped and this can contribute to furnace operation control.

However, this method has the disadvantage that the entire drop profile must be estimated by measuring only one point on the surface of the raw material layer 4.

In other words, since this method grasps the stacked state of the raw material layer 4 in a fixed manner and completely ignores changes in the stacked state due to accidents such as cargo collapse or hanging on shelves, it is not possible to rely on the measurement results as is. Extremely dangerous.

Furthermore, since it is a one-point measurement method, errors related to the rough measurement can lead to misinterpretation of the overall profile, so it is difficult to recommend this method.

FIG. 2 shows an improved method, in which instead of vertically fixing the wire guide tube 5, a lance 9 is passed through the lance 9 so as to move forward and backward in the direction of the arrow, and the wire 6 is inserted into the lance 9.
The structure of the seals inside and outside the furnace is as shown in FIG.

That is, connecting tubes 11 and 12 are attached to the iron shell 1, seal boxes 20, 21, and 22 are welded to the connecting tube 12, and a packing 17 that is in close contact with the outer peripheral surface of the lance 9 is inside the seal box 22. will be placed.

Furthermore, a sealing lid 14 attached to a rotating arm 15 is brought into contact with one end of the intermediate cylinder 13 to shut off the inside and outside of the furnace. Turn and retreat to the dotted line position.

18 and 19 are turn rolls installed inside the lance 9,
A weight 7 attached to the tip of the wire 6 is housed in the retraction window 23, but when the lance 9 is inserted into the blast furnace, the wire 6 is loosened and the weight 7 moves into the raw material layer 4 as shown in FIG. land on top.

The fact that the wire 6 is wound around the drum and that back tension is applied is exactly the same as in the case of FIG. 1.

By the way, the apparatus shown in FIG. 2 is an improved version of the apparatus shown in FIG. 1, and is designed for the purpose of performing measurements at multiple points.

Therefore, when the measurement at one point is completed in accordance with the procedure shown in FIG. lower and repeat the same measurement.

Then, the profile of the raw material layer 4 is estimated by comprehensively judging these.

However, in this device, since the lance 9 and the seal 17 are in close contact with each other, the sliding resistance of the lance 9 is extremely large.

Therefore, there is a problem that the sealing function of the seal 17 deteriorates while the lance 9 is being slid, and the seal 17 must be replaced each time the cross-sectional shape or size of the lance 9 is changed.

Furthermore, if the sliding resistance varies due to these factors, there is also the problem that the accuracy of each stopping position of the lance 9 deteriorates when the stopping position of the lance 9 is changed and measurements are made at multiple points over time.

Therefore, a large number of wires 6 are inserted into the lance 9, and the lance 9
It is also possible to use a simultaneous multi-point measurement method in which several holes are provided along the side wall of the hole and the wire is lowered through each hole.
3) causes gas leakage every time it passes the position of the gasket 17, and furthermore, there is a disadvantage that it becomes difficult to insert and withdraw the gas.

Furthermore, each of the above measurements must of course be completed before the next charge is charged, but if such time constraints are strong, it may be possible to measure only a few points, even though it is called multi-point measurement. Many, sometimes even only one measurement can be made.

Therefore, the method shown in Figure 2 is essentially the same as that shown in Figure 1,
Considering the loss time required to move Lance 9 in and out, it may actually be a disadvantage.

However, in the case of Fig. 1, in principle only one point can be measured, and we believe that there is room for improvement in the method shown in Fig. 2, so we are particularly considering a measuring device that can measure multiple points simultaneously. The present invention has been completed.

That is, the measuring device of the present invention is configured such that a horizontally long seal box is connected to the outside of a vertical furnace, and a lance stored in the seal box can be moved in and out of the furnace in a radial direction. A drive motor is provided outside the seal box, and a drum is wound around the rear end of a plurality of wires stretched along the lance and with weights attached to the tip side so that they can be freely fed out and retracted. It is built in the rear end, and has a drum rotation hydraulic motor and a drum rotation angle transmitter installed outside the seal box.

That is, the lance is built into the seal box, and there is no need to consider sliding contact with the seal, so there is no inconvenience when moving the lance in and out.

Therefore, if there is only one wire outlet (one wire),
The lance can be moved in and out quickly and accurately even when performing multipoint time-lapse measurements point by point, and it is also possible to use a large number of wires and lower them from several locations, but it is possible to For multi-point time-lapse measurements, the first measurement point and the second
The measurement time points after the first measurement are different, and it is necessary to take into account the fluctuation factors that occur over time when making a judgment.

However, if the surface of the raw material layer 4 is extremely uneven or has a large slope, the position of the weight may swing back and forth or from side to side depending on the way it lands, or the weight may fall over, causing the length of the wire to change. When the positioning error of the lance 9 is added to these errors, the reliability of the measured value is inevitably extremely low.

Therefore, in the present invention, it is essential to use a multi-point simultaneous measurement device in which a large number of wires are stretched, but it is natural that the design can be changed depending on the number of wires stretched. Non-violent modifications are within the scope of the invention.

FIG. 4 is a schematic sectional view showing the entire structure of the embodiment device.

FIG. 5 shows its plan view.

A deck 24 is attached to the upper side wall of the blast furnace by appropriate means, and a horizontally elongated seal box 25 is attached to its upper surface.

Since the inside of the seal box 25 is exposed to the blast furnace atmosphere, the inside needs to be completely shielded from the outside air.

Although the figure shows a gate valve type sealing mechanism that closes off the front part of the seal box when the lance 9 retreats, a check valve type sealing mechanism shown in FIG. 3 may also be used.

A driving sprocket 28 and a driven sprocket 29 are arranged within the box 25, and the rear end of the lance 9 is attached to a link chain 26 stretched across these.

The structure of the mounting part is as shown in FIG. 9, and the lance 9 shown in the figure is made of H-shaped steel.

That is, a link chain 26 is stretched between a pair of sprockets 28 (or 29) that are each pivotally supported in a cylindrical seal box 25, and an L-shaped piece 30 is attached to the lower chain 26. Installed in pairs on the left and right,
The mounting piece 30 is fixed to the side wall surface of the lance 9. Therefore, when the link chain 26 rotates, the mounting piece 30 moves accordingly, and the lance 9 runs in the length direction.

Note that 31 in FIGS. 4 and 6 is a grooved roller that supports the side wall plate of H-beam steel from below.

Reference numeral 39 denotes a lance holding roller which prevents the rear end from springing up due to the weight of the front end when the lance 9 is protruded to its most extreme position as shown in FIG. 4-6.

The structure for attaching the link chain 26 and the lance 9 is the fifth one.
For example, the method is not limited to the one shown in the diagram, but may include attaching a bottom plate along the longitudinal direction of the H-shaped steel, integrally protruding a side plate from the rear part of the bottom plate, and attaching this side plate to a part of the link chain 26. Good too.

However, in this case, it is preferable to use a normal cylindrical roll instead of the grooved roll 31.

FIG. 6 is a sectional view showing the front end of the seal box 25, showing the gate valve 40, manholes 41, 42, etc.

Note that 32b will be described later. 43 to 48 are manholes.

The structure of the rear end of the seal box 25 is as shown in FIG. 7 (partially cut away side view) and FIG. 8 (center part cutaway plan view), and includes a drive motor 27 that rotates the sprocket 28.
is placed outside the box 25 to protect it from contamination by high-temperature exhaust gas from the blast furnace.

Also, eight drums 33 wind each wire 6 (eight wires in the figure).
(two rows up and down, four rows on the left and right sides) are provided in the box 25, and a hydraulic motor 34 for winding or unwinding the wire 6.
The detection switch 35 detects a change in the descending speed of the weight, that is, the landing of the weight on the charge, and the current transmitter 36 detects and transmits the rotation angle of the drum 33. It is provided outside the seal box 25 for this purpose.

Note that the wire 6 is a compensation wire for a temperature sensing thermocouple that will be provided incidentally, and the thermocouple itself will be provided at the tip of the lance 9.

The wire wound around each drum 33 is attached to a guide roller 37
is arranged parallel to the lance 9, and is deflected downward by turn rollers 18 (FIG. 4) arranged at the tips of the lances 9, and a weight 7 similar to the above is attached to the tips of the lances 9.
can be installed.

A through hole is formed in the center plate of the H-beam steel corresponding to the lowering position of the wire 6 for the wire 6 to pass through, and when the lance 9 is retracted into the box 25, the wire 6 is wound up and the weight 7 is moved to the center plate. Pull up until it touches the bottom of the board.

Stoppers or proximity switches 32a and 32b are attached to the front and rear top surfaces of the lance 9, respectively, and are configured to instruct the backward and forward limits of the lance 9, respectively, and stop the motor 27. do.

The figure shows a state in which the lance 9 has reached its forward limit, but if the stop position in this state is inaccurate, the landing position of the weight 7 will become uncertain and measurement accuracy will decrease, which is not preferable.

Therefore, it is extremely important to provide a positioning mechanism as described above.

In addition, a dustproof lid 38 is placed on the upper surface of the lance 9, but when a cylindrical lance is used as the lance 9, it is natural that the above structure should be modified in design.

Incidentally, since the manhole provided in the seal box 25 is for inspection and cleaning, it can also be formed on the lower surface of the seal box 25.

The surface position of the raw material layer 4 is measured using this device as follows.

That is, initially, the lance 9 is at the retracted limit, the wire 6 is wound up, and the seal lid 14 seals the entrance of the box 25.

Then, when a new raw material is charged and a raw material layer 4 is formed, and the dust has stopped rising, the gate valve 40 is raised as shown in FIG. 6, and the drive motor 27 is activated to move the lance 9 forward.

At this time, it is necessary to make the weight 7 and the wire 6 follow each other, so the back tension by the hydraulic motor is weakened accordingly.

Then, the lance 9 and the weight 7 advance synchronously, and when the proximity switch 32b reaches the position of the lance pressing roller 39, the driving of the motor 27 is stopped.

However, if the force from the weight 7 and the wire 6 is adjusted so as to overcome the back tension of the hydraulic motor 34, the weight 7 will continue to descend with the wire 6, and eventually the raw material layer 4 will be lowered. land on the surface.

Since the tension applied to the wire 6 changes depending on the landing, the torque switch 35 is set to 1. Detect.

Note that there must be no two points when the wire 6 becomes slack due to its own weight, so there should be a small amount of slack in the hydraulic motor 34.

Pressure adjustment is also applied to the second wire so as to provide enough back tension to overcome the weight of the wire 6.

Here, a suitable scale is attached to the side surface of the drum 33.17. Then, the rotational position of the drum at the landing stage is determined by the current transmitter 3.
It is detected by 6.

Assume that the raw material is eventually consumed according to the reduction reaction in the blast furnace, and the raw material layer 4 has descended to the position 4, for example, and the weight 7
gradually descends while overcoming the back tension of the hydraulic motor 34 = q'yKl, and 7' tff-i? , = reach.

Since the amount of descent from position 7 to position 7' can be detected by the rotation angle of the drum 33, this information is obtained by the current transmitter 36.

Since this amount of descent (0 since it can be known for each length drum 33, that is, for each weight 7), it is possible to calculate the descent profile of the raw material layer 4 in the furnace.

Of course, the above detection can be performed continuously, but can it be performed intermittently at arbitrary intervals? J2.1゛Kin'gaki 1-11. You can also

Since the apparatus of the present invention is configured as described above, it is possible to accurately detect the distribution of the surface layer of the raw material in the vertical furnace and the state of its descent by simultaneous measurement at multiple points.

Therefore, it has become possible to not only adjust furnace operating conditions but also contribute to improving productivity.

[Brief explanation of drawings]

Figures 1 and 2 are conceptual diagrams showing the conventional measurement method, Figure 3 is the structure of the seal box in the conventional method, Figures 4-5 are conceptual diagrams of the equipment used to carry out the present invention, and Figure 6 is 7 is a cross-sectional view of the main part, FIG. 8 is a cross-sectional view of the central part, FIG. 9 is a cross-sectional view of the central part, and FIG. 6... wire, 7... weight, 9...
... Lance, 25 ... Seal box, 26
...link chain, 33 ... drum, 34 ... hydraulic motor, 35 ... current transmitter.

Claims (1)

[Claims] 1 A lance that penetrates the side wall of a vertical furnace and enters and exits in the radial direction is inserted into a seal box provided on the outside of the furnace wall during evacuation, and is suspended from multiple different positions along the longitudinal direction of the lance. The rear ends of a plurality of wires, each with a weight attached to the tip side, are wound around a drum provided at the rear end of the box, and a drive motor moves the lance forward and backward, applying back tension to the wire. A device for measuring the surface position of furnace contents, characterized in that a hydraulic motor for rotating a drum for feeding out or rolling in, and a drum rotation angle transmitter are each installed outside a seal box.