JPS58119319A - Interruption and venturi scrubber for blast furnace gas - Google Patents

Abstract

PURPOSE:To effectively utilize the air supply downtime of post process with the intention of allowing the interruption of gas and also of shortening of gas drawing time during the air supply downtime and also by cleaning gas during the operation period of the blast furnace. CONSTITUTION:A mechanism to control the water level in such a way as to keep the water level l3 or water sealing height h2 at 1m or higher in a diffuser 7, as shown by broken lines, by providing a control valve 21 for the water level of water sealing in the diffuser to an overflow pipe 19' branched from the middle between an urgent water drain valve 17 and a water interruption valve 18 for water sealing is provided. Also, an L-shaped primary pressure equalizing clean gas pipe 25 in which one end of the L-shaped device having a water sealing portion 24 with a water supply and drain pipe 22 for water sealing so as to keep it at a level lower than the lower end of the diffuser 7 is directed toward an opening 23 in the upper space of the VS body B is provided.

Description

[Detailed description of the invention] - Concerning lease scrubbers.

Conventional water seal valves for shutting off blast furnace gas when shutting off blast furnace gas generally include blast furnace 1, dust remover 2, venturi scrubber (hereinafter referred to as VS) 3, 3, as shown in Figure 1.
Continuing from I, the septum valve 4 is located 2vS 3' behind, so a blast furnace gas shutoff water seal valve 6 with an elevated tank is installed downstream of the siren valve 5, and when the gas is shut off, the water in the elevated tank is drained to shut off the gas. ing.

On the other hand, Venturi scrubber AIVS3, A2VS3・
The purpose of the AIV is to clean the gas during blast furnace operation, but the general structure and function of the AIV
In the example of S3 shown in Fig. 2 and Fig. 3, the VS main body B
In the upper center of the
S Body BK Cylindrical diffuser with holes open to the bottom end.
7 is inserted and fixed, and a cleaned 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 arranged at the top of the VS main body. It is set up. On the other hand, in the lower part of the VS main body, in order to maintain the state shown in Fig. 3 when the gas is shut off, there is a make-up water pipe 10 and a make-up water level control valve 1.
5 are arranged in series. Reference numeral 16 denotes an emergency discharge pipe in which an emergency discharge valve 17 and a water seal cutoff valve 18 are arranged in series, and 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 AIVS3, the water seal state during blast furnace operation is as shown in Fig. 2, when water W is supplied from the venturi water supply pump P through the syst throat part 20, the emergency drain valve 17 is closed, the water seal cutoff valve 18 is open, and the emergency With the cutoff valve 14 open, the water level is maintained at a height tl by the water level control valve 15, that is, with a sufficient space between it and the opening at the lower end of the diffuser 7. In this state, the gas G1 from the blast furnace enters the VS main body B, is cleaned, and is sent out through the clean gas outlet pipe 8. At the same time, when the pressure of the upper and lower bells is 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. 3, open the emergency drain valve 17, close the water seal cutoff valve 18, and close the emergency cutoff valve 14. After checking the overflow from the overflow pipe 19 so that the water seal height hl is approximately 500 mm, remove the ventilate pump P.
After that, in order to maintain the water seal height hl at 500 mm at all times, the make-up water valve]l is opened to create an overflow state. Therefore, in these facilities, when the blast furnace is shut down, the top side, that is, the upstream side. The effective water level is 500 mm1. 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 Fig. 3, so gas is pushed between the bells at the top and bottom of the furnace from the Enesen side, that is, the downstream side of the gas. It is impossible to shut off the gas when the blast furnace gas is turned off.

Therefore, as described above, the gas is shut off using the water seal valve 6 specially installed after the siren boo 5, which has the disadvantage that steam and N2 are used and the gas shutoff equipment becomes large-scale.

In order to solve the above-mentioned drawbacks all at once, the present invention provides a VS located closest to the blast furnace, that is, an AIVS 3, to have both the function of a venturi scrubber and the function of a water seal valve 6 for shutting off blast furnace gas, thereby cleaning the gas during blast furnace operation. When the wind is stopped, the gas can be shut off to shorten the degassing time. By effectively utilizing the wind break work time in the post-process, it eliminates wasted time, shortens the wind break time, reduces the amount of steam, and reduces the amount of N2. The purpose is to significantly reduce the

The apparatus of the present invention will be explained in detail below using 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 as a water seal valve for blast furnace gas diagonal when the blast furnace is shut down.

The first feature that differs from conventional VS is the emergency drain valve 1.
An overflow pipe 19 branched from the middle between the water seal cutoff valve 18 and the water seal cutoff valve 18 is installed so that the water level t3 in the diffuser 7, that is, the water seal height h2, is 1 m or more, as shown by the broken line, or for the same purpose. As another method, the height of the flow pipe 19 is kept at a level that fulfills the conventional function of preventing backflow, and a water level control valve 21 for the water seal in the diffuser is installed in the water seal. Height h2 is 1
The objective is to have a mechanism for controlling the water level so that the water level is equal to or higher than m.

Yet another feature is that the conventional primary pressure equalization clean gas pipe 9
Instead, one end of the L-shape, which is equipped with a water seal part 24 having a water seal water supply and drainage introduction pipe 22 so as to be at a level below the lower end of the diffuser 7, faces the opening 23 in the upper space inside the VSS main body. By providing the L-shaped clean gas pipe 25 for pressure equalization, a water seal is created and the connection between the furnace top and the 2VS is cut off, making it possible to cut off the gas during normal gas cutting with the AIVS.

The height level of the water seal part 24 is lower than the lower end of the diffuser 7, and the inlet pipe 22 is at the water level t during normal operation.
Located below Rubel. Therefore, its function is V during blast furnace operation.
In order to have the function as S, first, as shown in FIG. The emergency drain valve 17 is closed and the emergency cutoff valve 14 is held open by the water level control valve 15. Also blast furnace gas cutter 9
In order to operate as a gas cutoff function at the time, as shown in FIG. In this case, the gas pressure from the clean gas outlet pipe, that is, the gas pressure on the Enesen side is high, so the water level t2 in the VSS body and the water level t3 in the diffuser 7 are naturally the same. Therefore, the water level t2 is maintained at a level of 5 Q Otnm from the lower end of the diffuser as in the case of FIG.

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 Z-7 low tube from the VS main body and the diffuser 7, but there are 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 is possible to significantly shorten the degassing time, and also to significantly reduce the amount of steam and N2.

[Brief explanation of the drawing]

Figure 1 is an equipment flow diagram showing the location of a conventional venturi scrubber and water seal valve, Figure 2 is a conceptual diagram showing the water seal level during operation of a conventional venturi scrubber, and Figure 3 is a diagram of a conventional venturi scrubber. Fig. 4 is a conceptual diagram showing the water seal level during operation of the device of the present invention; Fig. 5 is a conceptual diagram showing the water seal level when gas is cut off in the device of the present invention. figure. B...vS main body 17...Emergency drain valve, 19...Overflow pipe 19', new overflow pipe 21...Water seal water level control valve 22...Water seal water supply and drainage introduction pipe 23...L-shape Mold opening 24...L-shaped water seal part 25-1 clean gas pipe for equalizing pressure

Claims (1)

[Claims] The venturi scrubber located closest to the blast furnace has a water seal height h2 of at least 1 m in the diffuser.
A water seal water level control valve or overflow pipe branched off from the emergency drain pipe is installed to ensure a water level of 100 mL, and a water seal section with a water seal water supply and drainage inlet pipe is installed so that the level is below the lower end of the diffuser. In addition to providing L
A venturi scrubber that also serves as a blast furnace gas cutoff, characterized in that a clean gas pipe for primary pressure equalization is provided with one end of the letter-shaped hole opening in the upper space of the main body.