JPS6219482B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for driving an induced blower in a converter exhaust gas treatment equipment, and uses steam generated during blowing in conjunction with the refining process to self-sufficient drive energy for the induced blower. This invention relates to a method for driving a self-sufficient induced fan.

The high-temperature CO gas generated from the converter is drawn into the exhaust gas treatment equipment by an induced fan, cooled and dust removed, and recovered as valuable gas in a gas holder.

The outline of the converter exhaust gas treatment device will be explained below with reference to FIG. In the figure, high-temperature CO gas generated in a converter 1 is drawn into a hood 3 by an induced blower 7, cooled by a cooler 4, and removed by dust removers 5, 6.
The gas is removed from the gas and collected as a valuable gas in the gas holder 10. Further, gas with low CO concentration at the beginning and end of blowing is released from the chimney 8 by switching the switching damper 9. Note that 2 is a skirt that seals between the furnace mouth of the converter 1 and the hood 3.

On the other hand, converter operation is carried out in the following steps. First, hot metal produced in a blast furnace is charged into a converter 1.
Hereinafter, this will be referred to as the pig iron receiving process. In this pig iron receiving process, the skirt 2 is raised and the converter 1 is tilted to receive hot metal. Next, the converter 1 is returned to an upright position, the skirt 2 is lowered and sealed, and pure oxygen is blown into the converter 1 from the oxygen injection lance 11 to remove the carbon contained in the hot metal in the converter 1. to react and decarburize. Hereinafter, this process will be referred to as the blowing process. Next, after the blowing process is completed, the skirt 2 is raised and the converter 1 is tilted, and the decarburized hot metal is transferred to the converter 1.
Take it out. Hereinafter, this will be referred to as the steel tapping process.

In this way, one refining process is completed through the pig iron receiving process, the blowing process, and the tapping process. In the next refining process, the pig iron receiving process, blowing process, and steel tapping process are performed in the same way, and by repeating these processes, a third refining process, a fourth refining process, and so on, are carried out in the converter operation. .

Among the above processes, during the blowing process, pure oxygen and carbon in the hot metal react and a large amount of CO gas is generated, but during the pig iron receiving and tapping processes, such gas is not generated. Hereinafter, the pig iron receiving, tapping and preparation processes are referred to as non-blowing time.

Now, the conventional induced blower is driven by an electric motor, and is driven not only during the blowing process but also during the non-blowing process.

During converter operation, CO gas is not generated during non-blowing periods, so driving the induced blower is not necessary, which has the disadvantage of wasting power.

In addition, Japanese Patent Application Laid-open No. 1206/1986 discloses a technology that uses both an electric motor and a steam turbine as the drive method for an induced fan, with the aim of supplementing the power consumption of the induced fan, but in this case as well, the induced fan had the disadvantage that it was operated continuously, and electricity or steam was wasted during non-blowing.

The present invention provides an induced fan that supplies steam to a steam turbine for driving an induced fan in accordance with the process of converter operation, eliminates wasteful steam consumption, and makes the induced fan self-sufficient in drive energy. The present invention aims to provide a driving method for the following.

That is, the present invention stores steam generated during the blowing process in a steam reservoir, and guides the stored steam to a steam turbine for driving an induced blower only during the blowing process.
While driving the induced blower, steam is generated during blowing to store the steam for driving the induced blower in the next blowing process, and during non-blowing, the steam supply to the steam turbine for driving the induced blower is stopped and the steam is constantly It is characterized by storing steam in a steam reservoir.

An embodiment of the present invention will be described in detail below. Referring to FIG. 2, the outline of the apparatus will be explained. In the figure, CO generated from converter 1 during the blowing process
The gas is induced by an induced blower 7 and is passed through the cooler 4.
After being cooled in a dust collector 5' and dust removed in a dust remover 5', the gas is recovered as a valuable gas. In addition, in the figure, 9 is a switching damper, and 8 is a chimney.

Inside the cooler 4, a radiant heat transfer section and a contact heat transfer section 19 each consisting of a large number of heat transfer tubes are provided, and cooling water is circulated by a circulation pump 15.

This cooling water is the high temperature CO generated from converter 1.
It is heated by gas (approximately 1200° C.), evaporates, and is led to the boiler drum 21. This boiler drum 2
Steam in the steam tank 1 is stored in a steam reservoir 12 via a pipe 16. The steam stored in this steam reservoir 12 is
Steam turbine 1 passes through piping 17 and electric valve 18
3 to drive the induced blower 7.

Note that 16' and 17' indicate the relationship with another exhaust gas treatment equipment, and usually a steelworks is equipped with a plurality of converters, and 16' indicates the connection with the steam system from the boiler drum of another exhaust gas treatment equipment. and 17' indicates piping that guides steam to the steam turbine 13 of another exhaust gas treatment device.

Now, in the first stage, for example, when there is no steam in the steam reservoir yet, it is necessary to obtain steam from a separately provided steam source to drive the turbine 13. In this manner, after the blowing process is started, steam is stored in the steam reservoir 12 during the blowing process, and in the next blowing process, the stored steam is used to drive the induced blower.

In the illustrated state during the blowing process, steam previously stored in the steam reservoir 12 is used to drive the steam turbine 13 and the induced blower 7 to perform the blowing process. On the other hand, the cooling water circulating through the radiation heat transfer section and the contact heat transfer section 19 by blowing is heated to an elevated temperature, evaporated, and stored in the steam reservoir 12. In this way, during the blowing process, the steam in the steam reservoir 12 is consumed and at the same time replenished, so that a constant amount of steam is always present in the steam reservoir 12.

During non-blowing, the electric valve 18 is closed by the signal 20 from the oxygen blowing lance 11, and the amount of steam in the steam reservoir 12 is maintained at a constant amount.

When the pig iron receiving process is completed and the next refining is to be performed, the electric valve 18 is opened in response to the signal 20 from the oxygen injection lance 11, and the steam in the steam reservoir 12 is circulated and supplied to the steam turbine 13, and the induction The blower 7 is driven, pure oxygen is blown from the oxygen blowing lance 11, and the blowing process is started. At the same time, steam is generated and stored in the steam reservoir 12.

As detailed above, according to the method for driving an induced fan according to the present invention, a steam turbine is adopted as the driving method for the induced fan, and steam is supplied to the steam turbine only during the blowing process, and steam is supplied to the steam turbine during the non-blowing process. By stopping the supply of steam and supplementing it with steam during blowing, a certain amount of steam is always stored in the steam reservoir, making it self-sufficient in driving energy for the induced blower, and eliminating unnecessary energy consumption. In addition to eliminating energy consumption, consumption power can also be largely eliminated, which has a significant effect in terms of energy conservation.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the entire converter exhaust gas treatment apparatus. FIG. 2 is a system diagram showing one embodiment for carrying out the method of the present invention. 1...Converter, 4...Cooler, 5, 6...Cooler, 7...
Induced blower, 11...oxygen blowing lance, 12...steam reservoir, 13...steam turbine.

Claims (1)

[Claims] 1. In a converter exhaust gas treatment device that cools the exhaust gas generated from the converter using a cooler, removes dust, and recovers the exhaust gas, the blower for drawing the gas generated from the converter into the exhaust gas treatment device is driven by a steam turbine,
During the blowing process, steam is generated and stored in a steam reservoir, and the stored steam is guided to a steam turbine for driving an induced fan only during the blowing process. Generates steam and stores the steam for driving the induced blower in the next blowing process,
During non-blowing, the steam supply to the steam turbine for driving the induced draft fan is limited to the purpose of keeping the turbine warm, and the supply amount is reduced, so that the steam is constantly stored in the steam reservoir. How to drive the induced blower of the device.