JPH0331762B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for recovering exhaust pressure gas from a top charging hopper of a blast furnace.

(Prior Art) When charging raw materials into a blast furnace, it is necessary to equalize and exhaust the pressure in the hopper so that high-pressure gas in the blast furnace does not blow out from the raw material charging port.

A typical conventional method will be explained with reference to FIG.

When opening and closing the seal valve 3 in order to charge the raw material charged into the charging port 2 of the blast furnace 1 into the small bell hopper 4, first close the secondary pressure equalizing valve 8 for the small bell hopper 4 to stop charging the pressure equalizing gas, and then After opening the exhaust pressure valve 6 to release the pressure inside the small bell hopper 4 to the atmosphere and eliminating the differential pressure between the upper and lower sides of the seal valve 3, the seal valve 3 is opened and closed to allow the raw material to fall into the small bell hopper 4.

Next, after closing the exhaust pressure valve 6, the primary pressure equalizing valve 5 is opened, and the primary gas purifier 22 is installed in the small bell hopper 4.
After passing the semi-clean gas, the small bell hopper 4 is filled until the pressure in the small bell hopper 4 reaches the semi-clean gas pressure (lower than the furnace top pressure), and then the primary pressure equalizing valve 5 is closed.
Next, the secondary pressure equalization valve 8 for the small bell hopper 4 was opened, and the high pressure gas stored in the receiver 12 was introduced, and the pressure in the small bell hopper 4 was made equal to the pressure in the large bell hopper 10 by the secondary pressure equalization control valve 9. Afterwards, the small bell 11 is opened and the raw material is dropped into the large bell hopper 10.

As described above, pressure equalization and evacuation operations are performed to charge raw materials, but recent high-pressure blast furnaces are often operated at a furnace top pressure of 2 kg/cm ² or more, and as a result, small The pressure inside the bell hopper 4 is also 2Kg/cm ²
When the above is reached, the seal valve 3 is opened and closed when charging the raw material.
When the exhaust pressure valve 6 is opened to reduce the pressure inside the small bell hopper 4, high-pressure blast furnace gas of 2 kg/cm2 or ^more is violently released into the atmosphere, which not only causes air pollution and noise, but also causes the blast furnace gas to be useful as fuel. You'll also lose gas.

Figure 3 (Special Publication No. 54-28809) and Figure 4 (Special Publication No. 56-23206) show ways to correct the above-mentioned shortcomings.
No.) has been proposed.

The system shown in Figure 3 partially recovers the blast furnace gas (at the time of primary exhaust pressure), so the above problems are somewhat resolved, but at the time of secondary exhaust pressure, due to the balance with the exhaust time. Since the gas inside the hopper is released into the atmosphere, problems such as air pollution, noise, and loss of blast furnace gas still remain.

In the case shown in FIG. 4, the entire amount is recovered and the reduction in pressure exhaust time is attempted to be solved by adopting an ejector 25, but the high pressure gas on the upstream side of the septum valve 26 is used for the ejector 25 ( In blast furnace equipment that has equipment to recover furnace top pressure as electrical energy,
The drawback remains that the recovered energy is reduced.

(Problems to be Solved by the Invention) The conventional technology described above violently releases high-pressure blast furnace gas into the atmosphere, which not only causes air pollution and noise, but also results in the loss of blast furnace gas useful as fuel. Another drawback was that the recovery efficiency of furnace top pressure as electrical energy was poor. The present invention makes it possible to recover the entire amount of gas in the furnace top hopper during exhaust pressure without reducing the recovery efficiency of the furnace top pressure as electrical energy.

(Means for Solving the Problems) The present invention utilizes the pressure loss of the blast furnace exhaust gas recovery pipe system in a device for discharging the pressure inside the hopper of a raw material charging device for blast furnace equipment. It is characterized by storing energy in a flywheel installed in the hopper, and by connecting the exhaust pressure pipe communicating with the hopper with the bypass pipe, the flywheel energy is used for recovering exhaust pressure gas from the hopper during exhaust pressure. A method for recovering exhaust pressure gas from a top hopper of a blast furnace charging device.

(Example) Hereinafter, one example of the exhaust pressure gas recovery method of the furnace top hopper of the present invention will be explained with reference to FIG. An energy storage device consisting of an impeller 19, a shaft 20, and a flywheel 21 is provided in the bypass pipe 27 connecting the upper and downstream parts of the secondary gas purifier 23,
Further, a bypass flow control valve 28 is provided upstream of the energy storage device, and a bypass cutoff valve 34 is provided downstream thereof. Normally, the pressure loss of the secondary gas purifier 23 is 2000 to 3000 mmAq (furnace top pressure 2.0 to 2.5 Kg/cm ²
In case of G), the bypass flow control valve 28 and bypass cutoff valve 34 are opened, and the bypass pipe 27 is opened.
By communicating with the flywheel, energy corresponding to this pressure difference can be stored in the flywheel. Here, the gas passing through the impeller 19 flows into the upstream side of the septum valve 26 of the clean gas pipe 24, so the efficiency of recovering the furnace top pressure as electrical energy is lower than when the flywheel 21 is not installed. There isn't. (Normally, the furnace top pressure recovery turbine uses the pressure difference before and after the septa valve).

When exhausting the gas in the small bell hopper 4,
First, the exhaust pressure primary recovery valve 2 installed in the exhaust gas pipe 17
9. With the exhaust pressure secondary recovery valves 31-1, 31-2 and the primary and secondary pressure equalization valves 5, 8 provided in the exhaust pressure recovery pipes 30-1, 30-2 all closed, close the exhaust pressure valve 6. Open. Next, when the exhaust pressure primary recovery valve 29 is opened, the gas inside the small bell hopper 4 is transferred to the dust remover 18 due to the pressure difference.
Because the exhaust gas flows through the clean gas pipe 24 on the downstream side of the septum valve 26, primary recovery of the exhaust gas is possible.
(Normally, the clean gas pipe 24 downstream of the septum valve 26
The internal pressure is about 700 to 800 mmAq, and there is a large pressure difference between it and the furnace top pressure). Furthermore, when the residual pressure in the small bell hopper 4 approaches the pressure in the clean gas pipe 24 (on the downstream side of the septum valve), the exhaust pressure primary recovery valve 2 is closed.
9, bypass flow control valve 28, and bypass cutoff valve 3
4 are both closed, and the exhaust pressure secondary recovery valve 31- is closed instead.
1 and 31-2, exhaust gas can be forcibly sucked and recovered by the energy stored in the flywheel 21 until the residual pressure in the small bell hopper 4 becomes equal to atmospheric pressure. The safety valve 32 provided in the outside air suction pipe 33 is connected to the flywheel 21
This is also to prevent the inside of the small bell hopper 4 from becoming negative pressure due to excessive suction by the impeller 19.

The bypass flow control valve 28 is used to adjust the amount of energy to be stored in the flywheel 21 and the amount of secondary recovery of exhaust gas. Also, due to the interlocking of the bypass flow control valve 28, the bypass cutoff valve 34, the exhaust pressure valve 6, and the exhaust pressure secondary recovery valves 31-1, 31-2, outside air flows into the small bell hopper 4 through the safety valve 32 more than necessary. can be prevented. That is, when the residual pressure in the small bell hopper 4 becomes approximately equal to atmospheric pressure, the exhaust pressure valve 6 and the exhaust pressure secondary recovery valves 31-1 and 31-1
1-2 and at the same time fully open the bypass flow control valve 28 and the bypass cutoff valve 34, the exhaust pressure process is completed and energy can be stored in the flywheel 21 again in the above-described manner. One of the major factors that makes it possible to put the present invention into practical use is that the energy accumulation time in the flywheel 21 can be sufficiently long compared to the pressure exhaust time. In addition, although the case where the pressure loss of the secondary gas purifier 23 is used has been described here, it is also possible to use the pressure loss of another part of the clean gas pipe 24 (for example, the primary gas purifier 22) to supply energy to the flywheel. There are also ways to store it. However, in this case, consideration must be given to dust contained in the clean gas.

The above are the steps of the exhaust pressure gas recovery method according to the present invention.

The raw material charging method and pressure equalization procedure are the same as the conventional method explained in FIG.

Although the above-mentioned exhaust pressure gas recovery method has been described with respect to a bell-type charging device, it goes without saying that this method can also be applied to exhaust pressure equipment of a bell-less type charging device.

(Effects of the present invention) According to the present invention, although the device is extremely simple, it is possible not only to prevent noise and air pollution caused by exhaust pressure in the blast furnace charging device, but also to avoid affecting the furnace top pressure recovery equipment. Blast furnace gas useful as fuel gas can be recovered without being released into the atmosphere, and furthermore, no other energy is consumed to recover the entire amount of blast furnace gas in the hopper.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a furnace top charging hopper uniform exhaust pressure device to which the method of the present invention is applied, and FIGS. 2, 3, and 4 are explanatory diagrams of the conventional method. 1...Blast furnace, 2...Charging port, 3...Seal valve,
4...Small bell hopper, 5...Primary pressure equalization valve, 6...
...Exhaust pressure valve, 7...Dry dust remover, 8...Secondary pressure equalization valve, 9...Secondary pressure equalization control valve, 10...Large bell hopper, 11...Small bell, 12...Receiver, 1
3... Rough gas pipe, 14, 16... Bleeder valve,
15...Semi-clean gas pipe, 17...Exhaust pressure gas pipe, 1
8... Dust remover, 19... Impeller, 20... Shaft, 2
1... Flywheel, 22... Primary gas purifier, 23... Secondary gas purifier, 24... Clean gas pipe, 25... Ejector, 26... Septum valve, 2
7...Bypass pipe, 28...Bypass flow control valve, 2
9...Exhaust pressure primary recovery valve, 30-1, 30-2...
Exhaust pressure recovery pipe, 31-1, 31-2...Exhaust pressure secondary recovery valve, 32...Safety valve, 33...Outside air suction pipe, 3
4...Bypass cutoff valve.

Claims (1)

[Claims] 1. In a device for discharging the pressure inside the hopper of a raw material charging device for blast furnace equipment, the pressure loss in the blast furnace exhaust gas recovery pipe system is used to store energy in a flywheel installed in the bypass pipe of the exhaust gas recovery pipe,
A furnace top hopper for a blast furnace charging device, characterized in that the energy of the flywheel is used to recover exhaust pressure gas from the hopper during exhaust pressure by connecting an exhaust pressure pipe communicating with the hopper to the bypass pipe. Exhaust pressure gas recovery method.