JPS5941305Y2 - Top gas turbine power generation equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a top-of-the-furnace gas turbine power generation equipment used to recover energy from gas discharged from the top of a blast furnace.

Conventionally, this type of power generation equipment has been proposed.
This is a combination consisting of one gas turbine for one blast furnace.

However, according to this, when there are multiple blast furnaces, it is economically disadvantageous to prepare a gas turbine for each blast furnace.

Furthermore, when looking at a single blast furnace, the furnace top pressure fluctuates, and when it drops, profitable energy recovery becomes impossible.

Therefore, as shown in FIG. 1, a combination of two blast furnaces and one gas turbine is considered.

That is, IA and IB are blast furnaces, and the gas discharged from the top of the furnace is Venturi scrubber 2A.

2B, 3A, and 3B, the furnace top pressure is adjusted by septum valves (furnace top pressure adjustment valves) 4A, 4B, and the gas is led to the gas main pipe 5.

6 is the septum valve 4A. A power generating device installed in parallel with 4B, which is always connected to the in-house power grid to take the load.The single-flow gas turbine 8 that drives the generator T has septum valves 4p, 4B. Pressure control valve 9 from the inlet side
A.

The gas taken in through 9B is supplied, and after driving the gas turbine 8, the gas is discharged to the gas main pipe 5.

By the way, an important point in achieving energy recovery efficiency depends on how low pressure loss can be kept.

Therefore, when the two blast furnaces IA and IB are operated under the same pressure conditions, that is, both gas pressures P1. P2 is P1=P
2, the turbine front pressure Po may be set to an upper limit value commensurate with the pressure.

However, it is actually P17! ! 'P2 is the case in most cases, so the detection signals A and B of the furnace top pressure controllers 10A and 10B are compared by the comparator 11, and the pressure control valves 9A and 9B are
Bypass circuit 12A provided between the downstream of the gas main pipe 5 and the gas main pipe 5
, 12B, the higher gas pressure P1. The one on the P2 side is opened by the control signals a and b of the comparator 11, thereby increasing the furnace top pressure P1. The turbine front pressure P is adjusted according to the low measurement of P2.

is lowering. In other words, since control can only be controlled by the blast furnace on the low-pressure side, it is at a disadvantage when comparing recovery rates, and the control becomes more complex, resulting in blast furnaces 1A and IBR.
This will require quite a long period of adjustment to ensure that there is no impact on the situation.

Furthermore, when the load of the generator 7 is cut off, fluctuations in the amount of gas generated at the top of the furnace are directly expressed as the front pressure of the gas turbine 8, and furthermore, when either the blast furnace IA or IB is out of operation,
It is not easy to control the speed to match the rotational speed.

The present invention provides a furnace top gas turbine power generation facility that can solve the above-mentioned problems, and one embodiment thereof will be described below with reference to FIGS. 2 to 4.

In Fig. 2, 20A and 20B are blast furnaces, and during operation, air is blown from blast furnace blowers 21A and 21B, and gases 22A and 22B discharged from the top of the furnace are venturi scrubbers 23A and 23.
B, 24A, and 24B, the furnace top pressure is adjusted at septum valves (furnace top pressure regulating valves) 25A, 25B, and the gas is led to the gas main pipe 2γ through dust removers 26A, 26B.

Reference numeral 28 denotes a power generation device installed in parallel with the septum valves 25A and 25B, which is always connected to the power grid in the plant via a circuit breaker 29 to take the load, and a gas turbine that drives the generator 30. 31 employs a double flow type in which a turbine rotor 32 is provided with a pair of left and right stages 33A and 33B.

The gases 22A and 22B are connected to septum valves 25A and 25B.
The turbine is branched from the inlet side, and passes through inlet cutoff valves 34A, 34B, pressure control valves 35A, 35B (on the other hand, 35B is a rotary governor valve), and emergency cutoff valves 36A, 36B (metal touch butter valve). The gases 22A on one side are guided into the middle of the rotor 32 separately, and the gases 22A on one side are
Then, the other gas 22B is supplied to the other stage 33B.

The gas used in both stages 33A and 33B is
γ and is discharged to the gas main pipe 2T.

Both pressure control valves 35A and 35B are each pressure controller 38
A, 38B, and one speed controller 39 is provided, from which the signals 40A,
40B is a double pressure control valve 35A.

35B can be selectively controlled.

The emergency cutoff valves 36A and 36B are configured to operate prior to the pressure control valves 35A and 35B when the load on the generator 30 is cut off.

Also, during blast furnace operation, it is necessary to keep the furnace top pressure as constant as possible, so the septum valves 25A and 25B are connected to the blast furnace 20A,
Furnace top pressure controllers 41A, 41 that detect the output pressure of 20B
The pressure control valve 3 is controlled by the control signals 42A and 42B from B.
5A, 35B are control signals 44A given from the automatic operation monitoring control panel 43 via the pressure controllers 38A, 38B.
, 44B, its opening degree is automatically controlled.

As shown in FIG. 3, the gas turbine 31 has a turbine rotor 32 supported by a pair of left and right bearings 45A, 45B. disk 4γA, 47
The rotor blades 48A and 48B are attached to the fixed outer cylinder body 46 via the annular members 49A and 49B.
0A and 50B form a pair of left and right paragraphs 33A.

33B is formed.

The outlet sides (outer end sides) of the paragraphs 33A and 33B communicate with outlet chambers 51A and 51B that are integrated with the fixed outer cylinder 46,
Further, the inlet side (inner end side) communicates with inlet chambers 52A and 52B integral with the fixed outer cylinder 46 via communication passages 53A and 53B.

Both rotor chamberers 52A and 52B are separated by a partition wall 54, and the left and right partitions 55 between the fixed outer cylinder 46 and the turbine rotor 32 have a simple structure such as a labyrinth packing or a water seal ring.

56A and 56B are the dust collection mechanisms of the outlet chambers 51A and 51B, and 57A and 57B are the inlet chambers 52A and 52B.
The dust collection mechanism is shown.

58A and 58B indicate gas seals provided between both ends of the turbine rotor 32 and the fixed outer cylindrical body 46.

Variable blades 59A, 5 are provided in the communication passages 53A, 53B.
9B, and a setting device 60A thereof.

60B is provided.

Next, the operating state of the gas turbine 31 will be shown based on FIGS. 2 and 4.

Blast furnace 20A in semi-operational stage. 20B is in operation, and septum valves 25A and 25B are automatically controlling the furnace top pressure.

First, the emergency shutoff valves 35A and 35B are fully opened by a start command.

Then, the rotational speed of the turbine rotor 32 is automatically increased by gradually opening the pressure control valves 35A and 35B.

A rotation speed signal 61 of this rotation speed is given to the control panel 43,
The control panel 43 also provides a control signal to the speed controller 39.

When the rotational speed becomes close to the rotational speed desired by the generator 30, the speed controller 39 controls either pressure control valve 35A, 35B to equalize the rotational speed.

When these rotational speeds are equalized, the power generator 28 is automatically joined, and from this point on, the power generator 28 enters synchronous operation.

Then, the output of the generator 30 automatically increases, and when a certain pressure is reached, the septum valves 25A, 25B and the pressure controller 38
The furnace top pressure is controlled by A and 38B in combination with pressure control valves 35A and 35B.

Thereafter, the septum valves 25A and 25B are closed (locked), and the furnace top pressure is controlled only by the front pressure control of the pressure control valves 35A and 35B, which brings about the desired operating state.

Next, the operation stop will be explained.

First, the septum valve 25A is activated by the operation stop command. 25B, and its opening control and pressure control valves 35A, 35
Moving on to the combination with front pressure control in B.

Immediately after that, the furnace top pressure is controlled by using only the septum valves 25A and 25B, and the opening of the valves is controlled to control the generator 3.
Automatically reduce the output of 0.

When the output of the generator 30 approaches [O], it is decoupled (load cutoff), but at the same time as this decoupling, there is a possibility that fluctuations in the amount of gas generated at the top of the furnace will directly appear as fluctuations in the pressure in front of the turbine nozzle. be.

Therefore, when the line is disconnected, the emergency shutoff valves 36A and 36B are closed in advance.

As a result, the volume of the pipe line downstream of the emergency shutoff valves 36A and 36B acts as an accumulator, and the gas turbine 31 is automatically decelerated and then stopped.

In the above embodiment, the case where both blast furnaces 20A and 20B are in operation is described, but even if one of the blast furnaces is out of operation, the emergency shutoff valve corresponding to the outgoing blast furnace is closed and the operation is stopped. The pressure control valve corresponding to the side blast furnace is connected to the speed controller 3.
By controlling the opening at 9, the desired power generation can be performed.

Note that during operation, the gas turbine 31 passes the gases 22A and 22B into the inlet chambers 52A and 5, as shown in FIG.
2B reaches the outer periphery of the intermediate portion of the turbine rotor 32, and due to the presence of the partition wall 54, it is distributed to the left and right and flows through the respective stages 33A and 33B, where the moving blades 48A and 48B
This causes the turbine rotor 32 to rotate, and is then discharged from the outlet chambers 51A, 51B.

Here, the gases 22A and 22B are inlet chamber 52A.

Although the pressure is high near 52B, the turbine rotor 3
Since it is supplied adjacent to the middle part of the partition 55, there is no problem even if there is leakage at the partition 55 part.

Also, since the pressure in the vicinity of the exit chambers 51A and 51B is sufficiently reduced, the gas seals 58A and 58
Even if a simple and inexpensive one is used as B, no leakage will occur.

According to the furnace top gas turbine power generation equipment of the present invention described above, a pair of left and right stages are provided on the turbine rotor, and one of the gases discharged from the two blast furnaces is supplied to one stage, and the other gas is supplied to the other stage. Because of this configuration, the generator can be operated under conditions without pressure loss whether two blast furnaces are in operation or any one blast furnace is in operation.

In addition, the pressure control valve and the emergency shutoff valve are arranged in sequence, and the emergency shutoff valve is configured to operate in advance when the load of the generator is cut off. The volume of the downstream pipe can also be used as an accumulator, and fluctuations in the amount of gas generated at the top of the furnace can be prevented from appearing as fluctuations in the pressure in front of the turbine nozzle.

In addition, one speed controller is provided, and the pressure control valve can be selectively controlled by this speed controller, so even if the blast furnace is not operating, the rotational speed of the gas turbine and generator can be adjusted. Speed regulation that matches the speed can be easily and reliably performed.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing a prerequisite embodiment, Figs. 2 to 4 show an embodiment of the present invention, Fig. 2 is a system diagram, and Fig. 3 is a partially cutaway front view of a gas turbine section. FIG. 4 is a time chart. 20A-, 20B... Blast furnace, 22A, 22B.
... Gas, 25A, 25B ... Septum valve, 28 ... Power generation device, 30 ... Generator, 31 ... Gas turbine, 33A , 33B・
... Paragraph, 34A, 34B ... Inlet shutoff valve, 35A, 35B ... Pressure control valve, 36A,
36B...Emergency shutoff valve, 38A, 38B...
...Pressure controller, 39...Speed controller, 41
A. 41B...Furnace top pressure controller.

Claims (1)

[Scope of utility model registration request] A pair of left and right stages are installed on the turbine rotor of the generator, and of the exhaust gas paths from the top of the two blast furnaces, one exhaust gas path is connected to one stage, and the other exhaust gas path is connected to the other stage. In both exhaust gas paths, a pressure control valve connected to a pressure controller and an emergency shutoff valve are installed in this order, and when the load of the generator is cut off, the emergency shutoff valve operates in advance of the pressure control valve. Further, one speed controller is provided, and this speed controller selectively controls one of the two pressure control valves when the rotation speed on the generator side approaches a desired rotation speed. Furnace top gas turbine power generation equipment characterized by being configured to enable.