JPH03281713A - Method for preventing invasion of furnace gas into sealing device for swinging chute driving device in bellless type vertical furnace - Google Patents

Abstract

PURPOSE:To surely prevent the invasion of furnace gas into swinging chute driving chamber by water-sealing upper and lower parts of a rotary table fitting the swinging chute and adjusting level difference between sealed water in a water sealing trough and drainage in a drainage tank. CONSTITUTION:The rotary table 21 for working the swinging chute is set in a casing 22 at furnace top of a blase furnace and a space between the fixed part 1 and rotary part in the furnace top wall 30 is water-sealed with the water sealing troughs 2, 10 having parting plates 5, 11. The sealed water supplied into the upper water sealing trough 10 through water supplying pipe 12, is fed into the lower water sealing trough 10 through a connecting pipe 24, and further, discharged into the drainage tank 9 through a drainage pipe 6. The above drainage tank 9 is made to a sealed construction and tip part of the drainage pipe 6 is submerged into the drain 13 in the tank and air-tightly connected with the above casing 22 through a communicating pipe 14. Further, the differential pressure between gas pressure in the casing 22 and gas pressure in the furnace is detected with a differential pressure gage 26 and the above drain 13 is drawn with a pump 16 so that this differential pressure is held plus to the set value to control gas volume in the drainage tank 9. By this method, the furnace gas is prevented from invading into the driving chamber 23 in the casing 22.

Description

[Detailed description of the invention] <j? For professional publication 'I! i'＞ The present invention secures the seal of the water seal mechanism installed between the rotating part and the fixed part of the rotating sudo drive device in a bellless blast furnace, and prevents top gas and dust from flowing into the drive chamber. This invention relates to a method for preventing top gas from being borrowed from a drive chamber for a swing shoe F drive device of a bellless type blast furnace, which can reliably prevent intrusion and reduce nitrogen gas supplied to a GJ drive chamber.

<Prior Art> In blast furnaces, a pelletless top charging device is used as a top charging device used to charge raw materials such as ore and coke into the furnace. This pellet-less type furnace charging device + i is equipped with a rotating shaft installed inside the furnace that is continuously rotated and tilted to distribute and charge the raw materials. It has advantages such as being able to make the temperature relatively low.

Conventionally, in a blast furnace among bell-less type vertical furnaces, as shown in FIG.
The gas seal and dust seal for the inside of the furnace of the rotary table 21 that performs JJ is achieved by blowing nitrogen gas, which has been cooled and dust removed in advance, into the drive chamber 23 formed in the casing 22 housing the rotary table 21, and then sealing the rotary table 21. The cooled exhaust gas is transferred to the annular gap (Srin 1-) between the fixed part 1 and the rotating part, that is, the cover 3 of the rotary table 21.
Discharging from the furnace into the furnace was carried out at ζ and L.

The heat input to the rotary table 21 by radiant heat from inside the furnace is at most 20,000ω! /)I, therefore, the amount of gas required for cooling is sufficient at 100ONj/h 1M degrees, but this supply amount prevents gas on from inside the furnace and entry of dust 1 into the drive chamber 23 in the casing 22. Couldn't prevent it. In order to effectively avoid the intrusion of gas and dust, 6000 to 10000 Nal/h of nitrogen gas is required, which increases the cost.

/, - In order to reduce the amount of cooling gas blown into the drive chamber 23 in the song 22, a sealing device for pressing an elastic body is provided on the slit t section between the fixed part and the rotating part of the rotary table 21 for sealing ( (See Japanese Patent Application Laid-open No. 61-62782, Japanese Utility Model Application No. 63-123994) or a means for storing carbon in a slit and pressing the carbon against the sliding surface (see Japanese Patent Application Laid-Open No. 61-87807) ) are disclosed.

However, these sealing means do not allow the elastic body or carbon to
Pressure against the moving surface causes severe wear and makes it difficult to maintain the sealing function over a long period of time, and the sole properties are insufficient, especially in the case of large high-pressure blast furnaces. The flow velocity is large, and in the end, it is necessary to prevent the gas inside the furnace and the officials from causing damage, for example, 200ONJ/
The problem is that you have to supply a cooling gas of more than I+.

In order to deal with these problems, Utility Model Application No. 63-1196
Japanese Patent Publication No. 50, No. 50 discloses a means for sealing a water seal tank and a partition plate disposed in the water seal gutter by connecting the tI;

That is, as shown in FIG. 2, the casing 22 at the top of the blast furnace
Rotary table 2 housed in drive chamber 23 formed inside
An annular water seal t'J10 is integrally provided on the upper part of the water seal 1, and a partition plate 11 to be disposed inside the water seal JALO is integrally provided on the fixed part 1. The cooling water necessary for the water 14 is pressurized by the water supply pump 4, and while measuring the amount of cooling water by the water supply flow rate resistance 8, the opening degree of the water supply Kffi adjustment lever r7 is adjusted to 11 points 2, and the water supply pipe 12 provided in the fixed part l is From Jubesui 1. l 4a l O.

In addition, an annular water seal tank 2 is integrally installed in a fixed part l corresponding to the lower part of the rotary table 21, and a water tank 24 is connected to the water pipe 10 provided at the upper part of the rotary table 21. (Used for cooling) ``ζζ lower water seal tank 2
The rotating chiffle 21, which constantly supplies the cooling water necessary for the water seal, is integrally provided with a partition plate 5 to be placed in the water I44a2, and the water seal tanks 2 and 11 are immersed in water. A partition plate 5 is used to seal the gap between the fixed part 1 and the rotating part. Furthermore, the lower water 11 and 2 are equipped with fJF water pipes that discharge cooling water to the system I, so that the IJ water is discharged.

Since the inside of the blast furnace is for commercial use, some water, t,
In order to prevent top gas from entering the drive chamber 23 formed in the glue casing 22, nitrogen gas is supplied into the drive chamber 23. tube 2
5 to N2 gas flow rate: Ii, 1 While adjusting the joint 29, nitrogen gas (L gas) is supplied and pressurized, and when the pressure is balanced with the furnace top pressure, the inside of the drive chamber 23 is cooled at once. there was.

However, even small fluctuations in the furnace top pressure can cause water sealing
The breathing phenomenon is suppressed by the sealed water in the water holder 2, and the water i,
The sealing pressure of 3L of water in l i 4M is 150 = 200 ff1
1nAql cannot be removed, so the furnace is in trouble ■Page pressure fluctuation is 4
There was a problem that the 7-piece (7-po water l, l) would tear when it was 1.

If the water seal is broken, water from the water 1,1 gutter will not only enter the furnace or the casing, but also cause water to leak into the water seal.
Gas and dust inside the furnace will not be able to seal properly.
This means that the rotary table drive device will not be adversely affected by entering the rotary table drive unit.

<Problems to be Solved by the Invention> Therefore, conventionally, the pressure detection pipes 27a and 27b connected to the differential pressure 5126 and inserted into the casing 22 and the furnace top wall 30, respectively, are used to reduce the pressure P2 in the drive chamber 23. and the furnace pressure P1 in the furnace top wall 30 is detected, and the differential pressure Δl) is equal to or higher than the positive pressure set value 2, that is, ΔP""P
! Nitrogen gas was supplied from the nitrogen gas supply pipe 25 so that -P+≧p≧0.

Specifically, the differential pressure ΔP is taken out as a process pressure variable by the differential pressure gauge 26 and manually inputted to the pressure adjustment 1it 28a, and from this differential pressure Δp and the above-mentioned positive differential pressure setting 1a p, the pressure adjustment 1it 28a generates the operation signal MV. The cooling N and barge control valve 29 are calculated based on the operation signal MV value.
The pressure inside the drive chamber 23 was set to be higher than the pressure inside the furnace top 27 (i!!p) by controlling the opening degree of the drive chamber 23. However, due to the above operation, the pressure P in the drive chamber 23 was always maintained. , and the pressure inside the furnace P, the differential pressure ΔP is the differential pressure set value p
In order to control the amount of N2 gas barge to a larger value, a large flow rate of N2 gas must be supplied to keep up with the pressure fluctuations in the furnace, which is uneconomical.

The present invention solves the problems of the prior art and provides a rotating shoe 1.
The seal of the water seal mechanism provided between the rotating part and the fixed part of the drive device is maintained at 6i, and the furnace ffI gas and dust 1 are kept in the drive chamber.
- In addition to thoroughly preventing the intrusion of
The object of the present invention is to provide a method for preventing the intrusion of top gas into a drive chamber-1 for a rotating chute drive device in a bell-less type blast furnace, which can save gas.

<Means for Solving the Problems> The present invention for achieving the above object includes installing a rotary table for rotating and tilting the rotary shear j-1 in a casing at the top of the furnace; And an annular water 144M between the fixed part and the rotating part at the lower part and the water 1
, 1 Arranged in a gutter-like annular shape 1, combined with a cutting board ・I
Saisho J is a bellless type vertical furnace equipped with a water seal mechanism called ゛ζ.
Knoll installation for a rotating unit drive device: 6. A method for preventing gas intrusion into a furnace, comprising the lower water J, I! The drain pipe taken out of the furnace is immersed in the waste water stored in the sealed JMi's waste water tank, and the soil part of the waste water tank and the top section of the furnace 1f1 where the rotary table is installed are airtight with a communicating pipe. is connected to I, and the drainage from the lower water seal tank is connected to I.
While guiding the gas into the drainage tank through the JF water pipe, the gas pressure inside the furnace top casing and the gas pressure inside the furnace are maintained at a positive differential pressure setting value or higher. This is a method for preventing gas intrusion into a furnace of a sole device for a swing chute drive device in a perless vertical furnace, which is characterized by extracting stored waste water and controlling the gas volume in the waste water tank.

<Saku Kawa> While guiding wastewater from the lower water seal tank into the wastewater tank via the drain pipe, the wastewater stored in the wastewater tank is made into a large-volume fJ by adjusting the amount of wastewater extracted from the wastewater tank.
1) [Water level in the water tank, that is, tJj The gas volume in the water tank is controlled, thereby increasing the differential pressure between the gas pressure in the furnace top casing and the gas pressure horn in the furnace to a predetermined positive pressure or higher. maintain it.

In this way, gas in the furnace is prevented from entering the drive chamber through the sealing device for the rotating chute drive device.

The principle of the present invention is that the drive chamber formed in the furnace top casing, which receives the influence 7P of fluctuations in the furnace internal pressure P1 at the furnace top through the water seal mechanism L7, is connected to the water tank 11 through a communication pipe. By controlling the level of tJt water stored in the tJr water tank t111, the "C gas volume is controlled, and the pressure in the drive chamber is controlled by t111.
“ζ is there.

Suppose that the gas volume of the drive chamber is V, and the gas volume occupied by ttt water ζ of the fJr water tank is ■. Then, the total gas volume becomes ■, F■. Furnace top pressure P.

To compensate and counter the fluctuation of P, X (V, I-
VT) - C (constant planting):] If you control it, it will be a good thing. Here, V and C are constant (direct, so the furnace Tn pressure 1) increases, the drain tank gas volume ■, becomes smaller, and conversely, if the furnace pressure p1 decreases, the furnace Tn pressure 1 decreases.
It will be operated so that it becomes thick.

<Example> Embodiments of the present invention will be described below with reference to the drawings.

In Fig. 1, the pressure is increased by the water supply pump 4, and while measuring the amount of cooling water using the water supply flow rate 8, the water supply '/r, and the opening degree of the control valve 7 are adjusted. water) from the water supply pipe 12 provided in the fixed part 1 to the upper water seal gutter 1
0. The cooling water supplied to the upper water 11 gutter 10 passes through the connecting pipe 24 (this is used for cooling the rotary table 21) and is sent to the lower water seal tank 2 through a water seal. It is now possible to supply.

Further, a drain pipe 6 for discharging cooling water outside the system is connected to the lower water seal φ2, forming a water cooling system, while a nitrogen gas supply pipe 25 is connected to the furnace top casing 22.
The N2 gas supply system for supplying nitrogen gas into the drive chamber 23 by adjusting the opening degree of the N2 gas flow valve 29 is the same as the conventional example shown in FIG.

In the present invention, the drain pipe 6 taken out of the furnace from the lower water seal trough 2 is immersed in the waste water 13 temporarily stored in the drain tank 9 having a sealed structure, and the upper part of the drain tank 9 and the rotary table 2 ! Furnace TFi top casing 2 with installed
2 and 2 are airtightly connected through a communication pipe +4. On the other hand, a tJ1 water extraction pipe 15 is connected to the lower end of the drainage tank 9, and while the amount of drainage is measured by the drainage flow mash 317 installed in the drainage extraction pipe 15, the JJt water pump 16 is operated by the drainage tank 9. A drainage system is formed to discharge 1 water containing 3JF of IJF water stored in the tank. In addition, a water level control tlB is provided in the waste water tank 90 to measure the level of the waste water 13 stored in the iJF water tank 9.

In the present invention, the nitrogen gas supplied from the nitrogen gas pipe 25 into the casing 22 is limited to being supplied in a biased manner at a constant low flow rate with two N8 gas flow ft1iJ joints set at a small opening. The pressure detection pipe 27a inserted into the furnace top casing 22 and the pressure detection pipe 2 inserted into the furnace top wall 30
The differential pressure ΔF) between the pressure P in the drive chamber 23 and the pressure P1 in the furnace is detected by the differential pressure 8126 connected to 7b, and the differential pressure ΔP is taken out as a process variable, and Δ1) is set to be positive (11!p). Above, that is, eight P””Pg P+
While guiding the wastewater from the lower water seal gutter 2 to the drain tank 9 through the drain pipe 6 so that ≧ρ>0, the wastewater stored in the drain tank 9 is drained. T] This is to adjust the amount of water discharged from 5.

At this time, the nt water from the uU water drain pipe 15 is
At t7F, set ΔII+ constant at 7 to reach the specified displacement amount.
This is done by controlling the rotation speed of the water pump 16.

Specifically, the pressure difference ΔP as a process variable extracted by the pressure difference 812G is adjusted! ! [Lead to t28b,
The positive differential pressure setting value PL input in advance to adjustment fl[L28b in °C! : Compare and perform operation 1 based on this comparison result.
No. 8 (MV value) is applied to the level adjustment 8131 having a Kasuri-1' control configuration, and the level llf! fI+'t131
The operation signal (MV(a) issued from
The rotation speed of the drainage pump 16 is controlled via the iJF water tank 9 to adjust the amount of drainage discharged from the iJF water tank 9. Note that the level signal of the waste water I3 detected by the water level meter 18 provided in the water tank 9 is received by the level controller 31, and the water level in the water tank 9 is grasped. ing.

For example, the gas pressure in the drive chamber 23 decreases due to the differential pressure ΔP<P, and due to small fluctuations in the pressure in the furnace, the upper 011 water seal] 0 and the breathing phenomenon of the water seal contained in the lower water seal 2 When there is a risk that furnace gas may enter the drive chamber 23 due to the pressure adjustment flff! t28b, level 1P I! 1
Li1, L and rotation speed 11i control 2; 1 via 19
No. 1 The rotation speed of the water pump 16 is set to low and U [water tank 9
Reduces the amount of wastewater extracted from the tank.

In this way, the 111 water led from the lower water I and I tower 2 to the drainage tank 9 is more concentrated than the FIL water extracted from the JIF water tank 9, and the water level in the iJt water tank 9 is -L.
As the temperature rises, the volume of the INF water tank 9 is reduced with L, and the gas in the water tank 9 is reduced with ti [J! l!
It is introduced into the tank 22 through the passage pipe 14 (the pressure in the drive chamber 23 is reduced by 1).

On the contrary, in order to prevent a situation in which the gas pressure in the drive chamber 23 is too high, conversely to the above case, the rotation speed of the IJr water pump 1G is set to a high speed, and the rotation speed from the inside of the drainage tank 9 is increased. tJr Increase the amount of water in the drainage tank 9? JIl water level and be down 11! , the gas volume In in the OF water tank 9 is increased, the gas in the cylinder 22 is introduced into the water tank 9, and the gas pressure in the drive chamber 23 is reduced.

In addition, the control as described in 0;l is performed when the drainage level in the water tank 9 is set to the upper limit level (1, wa) and the lower limit level (L,
J), and when the drainage level exceeds the upper limit level (L,) or the lower limit level (L,).
l) When the rotation speed is lower than that, the gas pressure is adjusted according to the conventional example explained in FIG. Due to the signal MV Hani from the device 28a, N! Nt gas flow ffi arranged in the gas pipe 25
The gas pressure is controlled by the amount of nitrogen gas supplied into the drive chamber 23 by increasing the opening degree of the adjustment #29.

While this control is being performed by supplying nitrogen gas, the rotation speed controller 32 controls the rotation speed of the drainage pump 1G to control the drainage level in the water tank 9 and set the level to 146. It goes without saying that the IJF gas tank 9 recovers during the period t and prepares for control based on the gas volume 1 in the IJF gas tank 9.

In the above-mentioned embodiment, the case where the drainage m discharged from the drainage tank is adjusted by the rotation speed-controlled drainage pump installed in the drainage extraction pipe was explained. 'tHJ adjustment brake installed
It is possible to perform the same procedure for other tJII water extractions such as the upper stage of water extraction.

<Effects of the invention> Below-L explanation 1. According to the present invention, not only can gas intrusion into the drive chamber from the sealing device for the rotating chute drive device be reliably prevented, but also the amount of nitrogen gas used can be significantly reduced, and the effects thereof are significant. There is something.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a seal device for a swing chute 1-drive device according to an embodiment of the present invention, FIG. 2 is a sectional view showing a seal device for a swing chute drive device according to a conventional example, and FIG. ] - It is a schematic sectional view of a drive device. 1... Fixed part, 3... Cover 5... Partition plate, 7... Water meter control valve, 9... tJ [water tank, 2... Lower water seal gutter, 4...・Water supply pump, 6...Drain pipe, 8...Water flow ffHf, IO...Upper water seal section, 11...Partition plate, 13...Drainage, 15...0 [Water drainage] 17...Drain flow rate needle, 19...Rotation speed controller, 21...Rotary table, 23...Drive chamber, 25...N2 gas supply pipe, 27...Pressure detection pipe, 29...N, gas flow rate adjustment b, 31...Level 1llllfT! L. 12...Water supply pipe, 14...Communication pipe, 16...Drainage pump, 18...Drainage level needle, 20...Swivel switch, 1. 22...Casing, 2i...Connecting pipe, 26...Differential pressure old, 28...Pressure adjustment ■1. 30...Furnace top wall, special applicant Kawasaki Steel Co., Ltd. Figure

Claims (1)

[Claims] A rotary table for rotating and tilting the rotating chute is installed in the casing at the top of the furnace, and an annular water seal is installed between the fixed part and the rotating part at the upper and lower parts of the rotary table, and an annular water seal is installed inside the water seal. A method for preventing gas intrusion into the furnace of a sealing device for a swing chute drive device in a bellless type vertical furnace equipped with a water sealing mechanism in combination with an annular partition plate arranged in the furnace, the method comprising: The drain pipe taken outside is immersed in the waste water stored in a drain tank with a closed structure, and the upper part of the drain tank and the furnace top casing in which the rotary table is installed are airtightly connected by a communicating pipe, While guiding the waste water from the lower water seal gutter into the drain tank through the drain pipe, the differential pressure between the gas pressure in the furnace top casing and the gas pressure inside the furnace is maintained at a positive differential pressure set value or higher. Gas intrusion into the furnace of a sealing device for a rotating chute drive device in a bell-less type vertical furnace, characterized in that the gas volume in the drainage tank is controlled by extracting the wastewater stored in the drainage tank so as to How to prevent it.