JPS61223227A - Operating method for generating equipment on top of blast furnace - Google Patents

Abstract

PURPOSE:To maintain a furnace top pressure always on a fixed level while enable an electric power quantity to be generated in a high level, by changing a stationary blade angle of a gas turbine to regulate its front pressure or regulating the stationary blade angle and the opening of a governing valve on the basis of the furnace top pressure of a blast furnace. CONSTITUTION:A generating equipment, discharging B gas generated from a blast furnace 20 after a pressure of the gas in a furnace top of the blast furnace is detected by a furnace top pressure detector 1, feeds the gas to a dust collector 5 via a coarse grain duct dust remover 3. Further the B gas is stored in a gas holder via an inlet shutoff valve 8, governing valve 9, generating equipment 10, outlet shutoff valve 13 and a water sealing valve 14. Here a furnace top pressure signal (i) of the B gas is given to a furnace top pressure adjusting indicator 2, and it outputs a difference between the target pressure iO of the furnace top pressure and the furnace top pressure signal (i) to an electric governor 19 as an operation command signal i1. And an output of the electric governor 19 is given to each oil hydraulic unit 21a-21c of each stationary blade angle regulator 11a-11c and a valve regulator 9a of the governing valve 9 in a gas turbine 11 constituting a part of the generating equipment 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of operating a power generation facility that utilizes gas discharged from the top of a blast furnace. An operating method in which the amount of power generation is controlled to a constant amount by adjusting the turbine front pressure by changing the stator blade angle or by adjusting the stator blade angle and the valve opening of a regulating valve provided at the front stage of the gas turbine. Regarding.

[Prior art]

The blast furnace furnace top pressure is controlled by maintaining the blast furnace top pressure at a high pressure during operation, and this control can increase the amount of iron tapped and reduce the fuel ratio. Conventionally, the above control is As shown in the figure, blast furnace gas discharged from the top of the blast furnace 20,
For example, the furnace top pressure of B gas is detected by the furnace top pressure detector 1 installed at the furnace top, and the detected value is output to the furnace top pressure indicator - cylinder needle 2, and the pressure value set there and the detected value are Find the deviation, B
Gas is blast furnace20. This was done by operating the valve driving device 4 provided in the secondary dust collector 7 of the peripheral dust collector 5 to which the coarse dust is sent via the dust remover 3 to adjust the internal pressure on the blast furnace side, based on the deviation.

Then, the B gas discharged from the secondary dust collector 7 is transferred to the regulating valve 9
The pressure energy is sent to the gas turbine 11 via the gas turbine 11, where the pressure energy is converted into electrical energy by the power generation facility 10 consisting of the gas turbine 11 and the generator 12, and then sent to the gas holder (not shown). It is designed to be stored in Furthermore, when the B gas pressure at the top of the furnace is high, for the safety of the equipment, the power generation equipment 10 is provided with a bypass pipe 1B having a bypass valve 17 in parallel therewith.
.

The gas turbine 11 has a built-in stator vane with a variable angle that can reduce the pressure of the gas passing through it and increase the gas velocity, but since the stator vane angle cannot be changed while the gas turbine is operating,
remains fixed.

[Problems to be Solved by the Invention] The gas turbine 11 generally has a stator blade angle with a certain margin in order to cope with the case where the furnace top pressure and the turbine front pressure cannot be controlled to a constant pressure by the valve drive device 4. Since the angle is adjusted to a certain angle, when the amount of B gas generated is lower than usual, such as when charging raw materials, the pressure in front of the turbine decreases and the amount of power generated decreases.

Further, a speed regulator 1p9 (see FIG. 3) with a fixed opening is provided on the inlet side of the power generation equipment 10. Since this valve opening degree is determined according to the processing capacity of the gas turbine 11, when the amount of B gas generated is large, that is, when the furnace top pressure becomes high, it is necessary to increase the amount of B gas released to the bypass 18. There was a problem in that the ratio of the amount of power generated in the power generation equipment IO to the furnace top pressure became low.

゛ [Means for solving the problem] The present invention has been made to solve the problem, and it is an object of the present invention to adjust the turbine front pressure by changing the stator blade angle of the gas turbine based on the furnace top pressure. A blast furnace that can maintain a constant furnace top pressure at all times by adjusting the stator vane angle and the opening degree of the regulating valve, and can also generate electric power at a high level according to the furnace top pressure. The purpose is to provide a method for operating top power generation equipment.

The operating method of the blast furnace top power generation equipment according to the present invention is such that a power generation gas turbine driven by gas discharged from the blast furnace top is equipped with a stationary blade angle changer, and the top pressure is detected by a furnace top pressure detector. When the furnace top pressure is above a predetermined pressure, the stator blade angle changer is driven according to the furnace top pressure to change the stator blade angle during gas turbine operation, and when the detected furnace top pressure is below the predetermined pressure. In case,
The stator blade angle is fixed at the angle at the predetermined pressure, and the valve opening of the regulating valve provided on the gas inflow side of the gas turbine is changed during gas turbine operation according to the furnace top pressure, and the amount of power generated is is characterized by controlling it to a constant amount.

〔Example〕

The present invention will be specifically explained below based on the drawings.

FIG. 1 is a schematic diagram showing the implementation state of the present invention.
0 indicates a blast furnace. The 9B gas generated from the blast furnace 20 is discharged from the top of the furnace after the pressure at the top of the furnace is detected by the furnace top pressure detector 1 installed at the top of the blast furnace 20, and is discharged from the top of the furnace. The dust is sent to the dust collector 5 via the dust remover 3.

The dust collector 5 consists of a primary dust collector 6 on the inlet side and a 2nd collector 1117 on the outlet side.
B gas is collected here and then discharged to the inlet shutoff valve 8. Speed regulating valve 99 power generation equipment 10. Outlet shutoff valve 13. After passing through the water seal valve 14 in order, the gas holder (not shown)
is stored in In addition, the B gas discharged from the dust collector 5 is
Inlet cutoff valve s, m speed valve 9, power generation equipment 10. Outlet shutoff valve 1
After passing through a bypass pipe 18 equipped with a bypass valve 17 provided in parallel with 3, the gas is stored in a gas holder via a water seal valve 14.

Gas turbine 11 that constitutes a part of the above-mentioned power generation equipment 10
For example, the structure has three stages of stator blades, and l.

The angle of each stator vane in the 2 and 3 stages can be changed by a stator blade angle adjusting device, for example, hydraulic cylinders lla, 11b, and 11c.

The furnace top pressure signal i of B gas detected by the furnace top pressure detection If is given to the furnace top pressure indicating controller 2. The furnace top pressure indicating controller 2 indicates the target pressure i of the furnace top pressure.

is set, and the difference between this target pressure ig and the input furnace top pressure signal i is output to the electric governor 19 as an operation command signal f1.

The output of the electric governor 19 is transmitted to the hydraulic cylinders 11a and 11b.
.

Hydraulic bags ff21a, 21b, 21 that control 11c, respectively
c F. Also, the valve control device 9 that adjusts the valve opening degree of the speed regulating valve 9
a, as shown in FIG.

In other words, when the operating m-order signal i1 is less than or equal to the set value A set for the electric governor 19, in other words, i is i(
In the case of 1+ A or more, the stator blade angle of all three stages of stator vanes or the first or second stage of them is set by the operation command signal i.
Hydraulic device 21 is used to control changes depending on the level of I.
A control signal is output to a, 21b, and 21c.

Note that the above set value A is the output value to the hydraulic system of the electric governor regarding the furnace top pressure control pipe fJIJa, which can be controlled by changing the stator vane angle, and the furnace top pressure, which can be controlled by adjusting the valve opening of the governor valve, which will be described later. It is determined based on the ratio of the former to the sum of the output value to the valve adjustment device of the electric governor regarding the pressure control range.

Therefore, even if the furnace top pressure increases, by changing the stator blade angle, the gas turbine can maintain the furnace top pressure constant without reducing the amount of power generated by the power generation equipment.

In addition, when the operation command signal iI exceeds the set value A, in other words, when 1 becomes lower than ig + A, the stationary blade angle is adjusted to the angle at the set value A, and in addition to this, 11 is set to A. In order to adjust and control the valve opening of the speed regulating valve 9 according to the degree of exceeding the above, control signals are output to the hydraulic bags f21a, 211>, 21c and the valve adjustment device 9a, respectively. As a result, even when the furnace top pressure is low (and the furnace top pressure cannot be controlled only by the turbine front pressure), by changing the valve opening of the governor valve 9, the gas turbine 11 and the governor valve 9 can control the furnace top pressure. It can be maintained constant, and the power generation amount of the power generation facility 1o does not decrease.

Therefore, in the present invention, the amount of Wi emitted does not decrease regardless of the level of the furnace top pressure, and the furnace top pressure can always be maintained constant.

In the above embodiment, the furnace top pressure indicating controller 2. electric governor 1
9 is used, but the present invention is not limited to this, and the present invention is not limited to this.
Of course, it can also be implemented as a configuration in which control valves a, llb, llc and the regulating valve 9 are controlled.

〔effect〕

As described in detail above, the present invention adjusts the turbine front pressure by changing the stator blade angle of the gas turbine based on the furnace top pressure, or adjusts the stator blade angle and the valve opening of the governor valve. Regardless of whether the pressure is high or low, the amount of power generated does not decrease, and the amount of power generated can be increased compared to conventional methods, and the top pressure of the furnace can always be maintained constant.
For this reason, the amount of blast furnace gas escaping to the bypass valve is reduced, and since the regulating valve and stationary blade angle are adjusted, the valve throttling loss of the regulating valve can be reduced, and other excellent effects are achieved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the implementation state of the present invention, FIG. 2 is a graph showing an example of the output of an electric governor, and FIG. 3 is an explanatory diagram of the prior art. l...Furnace top pressure detector 9...Governing valve 11...
・Gas turbine 11a+ 11b+ llc...
Hydraulic cylinder 19...Electric governor patent Applicant: Sumitomo Metal Industries Co., Ltd. Agent Patent attorney: Noboru Kono 1 energy output 121!1 131!1

Claims (1)

[Claims] 1. A power generation gas turbine driven by gas discharged from the blast furnace top is equipped with a stationary blade angle changer, and when the furnace top pressure detected by the furnace top pressure detector is higher than a predetermined pressure, The stator blade angle is changed during gas turbine operation by driving a stator blade angle changer according to the furnace top pressure, and when the detected furnace top pressure is below a predetermined pressure, the stator blade angle is changed to the stator blade angle at the predetermined pressure. The valve opening of the regulating valve, which is fixed at a fixed angle and provided on the gas inflow side of the gas turbine, is changed during operation of the gas turbine according to the furnace top pressure, thereby controlling the amount of power generation to a constant amount. How to operate blast furnace top power generation equipment.