JPH0221848B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water seal valve for shutting off blast furnace gas and a ventilium scrubber.

Conventional water seal valves for shutting off blast furnace gas when shutting off blast furnace gas generally consist of a blast furnace 1, a dust remover 2, a ventilator scrubber (hereinafter referred to as VS) 3, 3', and a septum valve 4, as shown in Figure 1. is 2VS
3', a blast furnace gas cutoff water seal valve 6 with an elevated tank is installed downstream of the silencer 5.
When the gas is shut off, the water in the elevated tank is drained to shut off the gas.

On the other hand, Bench Uly Scrubber No.1VS3, No.2VS
The role of VS 3' etc. is to clean gas during blast furnace operation. In the upper center of the main body B, a cylindrical diff user 7 with an open hole up to the lower end is inserted and fixed to feed gas from the blast furnace into the VS main body B as shown by arrow _G1 . A gas outlet pipe 8 and a clean gas pipe 9 for primary pressure equalization, which is fed during pressure equalization to equalize the pressure of the upper and lower bells of the furnace top charging device, are provided. On the other hand, a make-up water pipe 10 and a make-up water valve 11 are arranged at the bottom of the VS main body in order to maintain the state shown in FIG. 3 when the gas is shut off. Note that 12 is a sludge discharge valve. 13 is a normal drain pipe, and an emergency shutoff valve 14 and a water level control valve 15 are arranged in series. Again 1
Reference numeral 6 denotes an emergency discharge pipe in which an emergency discharge valve 17 and a water seal cutoff valve 18 are arranged in series. Reference numeral 19 denotes an overflow pipe which is branched from the middle between the emergency drain valve 17 and the water seal cutoff valve 18.

In this No. 1 VS 3, the water sealing condition during blast furnace operation is as shown in Figure 2.
The water W supplied through the throat portion 20 is controlled by the water level control valve 15 with the emergency drain valve 17 closed, the water seal cutoff valve 18 open, and the emergency cutoff valve 14 opened.
A sufficient space is provided between the height of _l1 , that is, the opening at the lower end of the differential user 7, and this is maintained. In this state, the gas _G1 from the blast furnace enters the VS main body B and is purified, and sent out from the clean gas outlet pipe 8. At the same time, when the upper and lower bell pressures are equalized, it is sent out from the primary pressure equalized clean gas pipe 9.

In addition, to cut off the backflow of gas from the blast furnace when the blast furnace is shutting down, as shown in FIG.
4 is closed, and after confirming overflow from the overflow pipe 19 so that the water seal height h ₁ is approximately 500 mm, the bench lily pump P is stopped, and thereafter the water seal height h ₁ is always maintained at 500 mm. Make-up water valve 11
These facilities are suitable for preventing gas backflow from the top of the furnace, that is, the upstream side, through the clean gas outlet pipe 8 when the blast furnace is shut down. In other words, for a gas pressure of 700 to 800 mmAq from the downstream side of the gas, there is only an effective water level of 500 mm, and at the same time, the clean gas pipe 9 for primary pressure equalization and the clean gas outlet pipe 8 are connected as shown by the arrow in Figure 3, so the EneSen side That is, since the gas is pushed between the bells at the top and bottom of the furnace from the downstream side, it is impossible to shut off the gas, and it is impossible to shut off the gas when the blast furnace gas is turned off.

Therefore, as mentioned above, the gas is shut off using the water seal valve 6, which is specially installed after the silencer 5, but since the degassing range is wide, it takes a long time to degas, which has a negative impact on the air suspension work. Disadvantages include the use of large amounts of steam and N ₂ and the need for large-scale gas shutoff equipment.

In order to solve the above-mentioned drawbacks all at once, the present invention has the VS located closest to the blast furnace, that is, No. 1 VS 3, have both the function of a ventilium scrubber and the function of a water seal valve 6 for shutting off blast furnace gas. When cleaning the gas and taking a break, the gas can be cut off to shorten the degassing time.By effectively utilizing the time for post-process blow-off work, you can eliminate wasted time, shorten the blow-off time, cut the amount of steam, and reduce the amount of steam. The aim is to significantly reduce the amount of ₂ .

The apparatus of the present invention will be explained in detail below with reference to the example shown in FIGS. 4 and 5.

FIG. 4 shows the functional state of the apparatus of the present invention as a VS during blast furnace operation, and FIG. 5 shows the functional state of the apparatus as a blast furnace gas cutoff water seal valve when the blast furnace is shut down.

The difference from the conventional VS is that the overflow pipe 19' branched from the middle of the emergency drain valve 17 and the water seal cutoff valve 18, as shown by the broken line, reduces the water level _l3 , that is, the water level inside the differential user. Seal height _h2 is 1m
Alternatively, as another means for achieving the same purpose, the height of the overflow pipe 19' may be kept at a level that fulfills the conventional backflow prevention function, and the water sealing water inside the differential user may be added to the height of the overflow pipe 19'. By providing a position control valve 21, there is provided a mechanism for controlling the water level so that the water seal height _h2 becomes 1 m or more.

Yet another feature is that the L-shaped water seal section 24 is equipped with a water seal water supply and drainage inlet pipe 22 at a level below the lower end of the differential user 7 in place of the conventional clean gas pipe 9 for primary pressure equalization. One end of the mold is VS
By installing an L-shaped clean gas pipe 25 for primary pressure equalization with the opening 23 facing the space above B in the main body, a water seal is created and the connection between the furnace top and 2VS is cut off.
1VS enables gas shutoff during normal gas shutoff. The height of the water seal portion 24 is lower than the lower end of the differential user 7, and the introduction pipe 22 is located below the water level _l1 during normal operation. In order to have the function of VS during blast furnace operation, the water level _l1 must be set at the lower end of the differential user 7 and at the L-shaped primary pressure equalizing clean gas pipe 25, as shown in Fig. 4. The emergency drain valve 17 is closed so as to have a sufficient space between the water and the water, and the emergency shutoff valve 14 is held open by the water level control valve 15. In addition, in order to operate as a gas cutoff function when the blast furnace gas is cut off, as shown in FIG. The height _h2 of the water seal inside is set to 1 m or more, because in this case the gas pressure from the clean gas outlet pipe, that is, the gas pressure on the Enesen side, is high.
Water level _l2 in VS body B and water level _l3 in differential user 7
are of course different. Therefore, the water level _l2 is maintained at a level 500 mm from the lower end of the differential user, as in the case of Fig. 3.

In addition, the backflow of gas from the blast furnace can be adequately countered by maintaining the same water level as shown in Figure 5 because the top side of the furnace is at atmospheric pressure.

Although it is different from the present invention, there is also a method of directly taking out the overflow pipe from the VS main body and the differential user 7, but this method has many disadvantages such as waste of water etc.

As described above, by using the device of the present invention that can perform both functions, it has become possible to significantly shorten the degassing time, and also to significantly reduce the amount of steam and N ₂ .

[Brief explanation of drawings]

Figure 1 is an equipment flow diagram showing the location of a conventional ventilium scrubber and water seal valve, Figure 2 is a conceptual diagram showing the water seal level during operation of a conventional ventilium scrubber, and Figure 3 is a diagram of a conventional ventilium scrubber. Fig. 4 is a conceptual diagram showing the water seal level during operation in the device of the present invention, and Fig. 5 shows the water seal level when the gas is cut off in the device of the present invention. Conceptual diagram. B...VS main body, 17...Emergency drain valve, 19...
... Overflow pipe, 19' ... Newly installed overflow pipe, 21 ... Water seal water level control valve, 22 ... Water seal water supply and drainage introduction pipe, 23 ... L-shaped opening, 24
... L-shaped water seal section, 25 ... Clean gas pipe for primary pressure equalization.

Claims (1)

[Claims] 1 The ventilate scrubber located closest to the blast furnace has a water seal height h ₂ in the differential user.
Install a water seal water level control valve or overflow pipe branched from the emergency drain pipe to ensure a water level of at least 1 m, and install a water seal water supply and drainage inlet pipe so that the level is below the lower end position of the differential user. What is claimed is: 1. A ventilary scrubber for blast furnace gas cut-off, characterized in that it is provided with a water seal section having a water seal section, and a clean gas pipe for primary pressure equalization having an L-shaped end opened in an upper space inside the main body.