JPS63162941A - Operating method for turbo type hot blast generating device - Google Patents

Abstract

PURPOSE:To reduce a fuel cost, by a method wherein, when during self- operation, the heating load of a burner is decreased to a set value or less, a motor fan for starting is run. CONSTITUTION:Motor fans 20a and 20b for starting and an intake air passage 17 with a check valve 19 are connected in parallel up a line from a compressor 12 for pressurizing and feeding air to a burner 2. Since, during self-operation, the heating load of the burner 2 is decreased to a set value or less, the motor fans 20a and 20b for starting are run. This constitution enables the burner to be actuated at an input responding to a heating load, and permits reduction of a fuel cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a compressor that compresses and supplies combustion air to a burner, and a gas turbine connected to a high-temperature gas supply path from the burner. This invention relates to a method of operating a turbo-type hot air generator in which a starting electric fan and an intake passage with a check valve are connected in parallel to the upstream side of a compressor.

[Conventional technology]

Conventionally, in the above-mentioned turbo-type hot air generator, the starting electric fan is activated to ignite the burner, and the amount of fuel supplied to the burner is increased compared to the time of ignition, so that the self-blade operation state is reached. An operating method was adopted in which the electric fan was kept stopped and the blade continued to operate on its own.

[Problem that the invention seeks to solve]

However, since the minimum input that enables self-blade operation is about 50% of the input during rated operation, if the heating target is something with large load fluctuations such as a boiler, no input is necessary even though the heating load is small. However, there was room for further improvement in terms of turndown ratio.

An object of the present invention is to provide a method that allows economical operation even when the heating load is small, without complicating the equipment, by using rational means that effectively utilizes the original configuration.

[Means for Solving the Problems] The characteristic means of the present invention is to reduce the heating of the burner during self-blade operation in which a gas turbine is driven by high-temperature gas from a burner and a combustion air supply compressor is driven by the gas turbine. When the load decreases below the set value, a starting electric fan installed upstream of the compressor in parallel with the intake passage with a check valve is activated, and when the starting electric fan is activated, the heating load of the burner is reduced to the set value. If the power increases above this level, the starting electric fan must be stopped, and its effects are as follows.

[For production]

In other words, it is effective that the startup electric fan has combustion air supply performance that can maintain good combustion in the burner until the input increases from the minute input at the time of ignition to the minimum input that allows self-blade operation. When the heating load of the burner reaches a set value approximately equal to the value corresponding to the minimum input that allows self-blading operation, the electric startup fan is activated without adding special equipment to increase the turndown ratio. This reduces the burner input commensurate with the heating load while maintaining good combustion in the burner and eliminating fuel waste.

In addition, when the heating load of the burner exceeds a set value that is approximately equal to the value corresponding to the minimum input that allows self-blade operation,
While stopping the starting electric fan and increasing the input to the burner in proportion to the heating load, good combustion of the burner is maintained with the air heated and supplied by the compressor, thereby eliminating power consumption by the starting electric fan.

〔Effect of the invention〕

As a result, it is not only possible to eliminate power consumption when the heating load is large, but also to make effective use of the originally provided startup configuration, without complicating the equipment, even when the heating load is small. The burner can be operated with appropriate input, eliminating fuel waste and achieving economical operation.

〔Example〕

Next, examples will be shown.

First, the configuration of the boiler to be operated will be explained with reference to FIGS. 1 and 2.

A combustion chamber (3) for the burner (2) is formed in the lower part of the first water tank (1), and a number of first smoke pipes (4) connected to the combustion chamber (3) are installed between the upper and lower portions of the first water tank (1). and burner (
2) to form a first heat exchanger (A) that evaporates the water stored in the first water tank (1) with the high temperature gas from the first water tank (1).

A large number of second smoke pipes (5) connected to the first smoke pipe (4) are provided above the water storage surface (tag) of the first water tank (1), and the high temperature gas from the burner (2) is supplied to the first water tank ( A second heat exchanger (B) is formed to superheat the steam generated in 1) and send it to the recovery path (6).

A second water tank connected to the water supply channel (7) is located above the first water tank (1).
A water tank (8) is provided, a number of third smoke pipes (10) connected to the second smoke pipe (5) and the exhaust passage (9) are provided in the second water tank (8), and water from the water supply channel (7) is supplied to the burner. In addition to preheating with high-temperature gas from (2), the water storage surface (tag) in the first water tank (1) is maintained within a set range by a hot water supply path (27) having a known automatic flow rate control means (26). A water preheater (C) for supplying hot water is formed.

In short, water and steam are passed through the feed water preheater (C), the first heat exchanger (A), and the second heat exchanger (B) in this order, and the burner (2
), the steam is heated with high temperature gas from the recovery channel (
6).

A compressor (12) is installed in the combustion air supply path (11) to the burner (2), and a damper (1) for adjusting the air volume is installed.
3), the primary air passage section (lla) and the secondary air passage section (llb) allow the fuel to be supplied under pressure from the fuel passage (14) equipped with the supply amount adjustment valve (14a) in an amount that can completely burn the fuel. The structure is such that air is supplied under pressure to the burner (2).

A gas turbine (16) driven by the high temperature gas is provided in the supply path (15) for sending high temperature gas from the first heat exchanger (A) to the second heat exchanger (B).
and a compressor (12) are interlocked and connected so that the compressor (12) is driven by the energy of the high-temperature gas.

A filter (18) and a check valve (19) are provided in the air intake path (17) of the compressor (12), and electric fans for first and second startup (20a) and (20b) are connected to the intake path (17) for second startup. On the discharge side of the electric fan (20b), a first
A reverse valve (28) is provided to allow the starting electric fan (20a) to operate independently, and the electric fan (20a), (20b) is installed when the burner (2) is ignited or when the boiler is under low load.
) to send combustion air.

Oil tank (21), electric oil pump (22),
An oil cooler (23) that utilizes cold water from the water supply channel (7) can be installed in the lubricating oil circulation path (25) for the bearing of the rotating shaft that links the gas turbine (16) and compressor (12) to the section (24). be.

A steam pressure detector (29) is provided in the steam recovery path (6),
An air pressure detector (30) is provided in the intake path (17) of the compressor (12).

Next, a method of operating the boiler will be explained with reference to FIG.

(a) The first starting electric fan (20a) is operated, a small amount Qs of fuel suitable for ignition is supplied to the burner (2), and the burner (2) is ignited.

(b) Increase the fuel supply amount, and when the fuel supply amount reaches the set amount Q, operate the second starting electric fan (20b).

(c) Increase the fuel supply amount to 02, and check the air pressure detector (30
), the first and second starting electric fans (
20a) and (20b), and the gas turbine (1
6) drives the compressor (12) to supply air from the intake passage (17) to the burner (2).

(2) When the boiler is in self-operation mode, the amount of fuel supplied is increased at once to Q, which corresponds to 100% load of the boiler, and the detected value of the steam pressure detector (29) is increased to P.

(e) Thereafter, the amount of fuel supplied to the burner (2) is adjusted from 02 to 02 in accordance with the load fluctuation of the boiler so as to maintain the detected value of the steam pressure detector (29) at the set value P1. Adjust within the range and continue self-blade operation for m.

(f) During self-blade operation, even if the fuel supply amount to the burner (2) is maintained at the minimum value 2 that allows self-blade operation, the detected value of the steam pressure detector (29) increases and reaches the set value P2. If you reach
First and second starting electric fans (20a), (20
b) to reduce the amount of fuel supplied to the burner (2) in accordance with the load fluctuation of the boiler so as to maintain the detected value of the steam pressure detector (29) at the set value P2. Adjust within the range of Q, to Q2.

(g) Under the conditions described in item (f) above, the fuel supply amount to the burner (2) is the minimum value Q that allows self-operation! Even if the detected value of the steam pressure detector (29) decreases and reaches the set value P1, the fuel supply amount is increased and the first and second starting electric fans (20a), (20b) is stopped, and the detected value of the steam pressure detector (29) is set to the set value p.

The amount of fuel supplied to the burner (2) is adjusted in the range of 02 to Q3 in accordance with the load fluctuation of the boiler so as to maintain the boiler.

σ Even if the fuel supply amount to the burner (2) is maintained at the above set amount port in the state described in (f) above, the steam pressure detector (2)
If the detected value of 9) increases and reaches the set value P3, then
The second starting electric fan (20b) is stopped, the fuel supply amount is decreased, and the detected value of the steam pressure detector (29) is set to P.
, the amount of fuel supplied to the burner (2) is adjusted in the range of Qs to Qs in accordance with the load fluctuation of the boiler.

Even if the amount of fuel supplied to the burner (2) is maintained at the set amount above in the condition described in (1) above, the steam pressure detector (29)
When the detected value decreases and reaches the set value P2, the second starting electric fan (20b) is operated, the fuel supply amount is increased, and the detected value of the steam pressure detector (29) is adjusted to the set value P2.
2, the amount of fuel supplied to the burner (2) is adjusted within the range of Q2 to Q2 in accordance with the load fluctuation of the boiler.

(2) Even if the amount of fuel supplied to the burner (2) is maintained at the above-mentioned small amount O8 in the state of item H above, if the detected value of the steam pressure detector (29) increases and reaches the set value P4, The fuel supply is stopped, the first starting electric fan (20a) is stopped, and the burner (2) is extinguished.

River After the burner (2) in the diagram above is extinguished, the steam pressure detector (
If the detected value of 29) decreases to the above set value P1, the above (
Put the blade into self-operation mode by performing the same operations as in item (a) or c), and then perform the same operation as in item (e) above.

Examples according to c] Next, another embodiment will be described.

The combustion method and fuel type of the burner (2) can be changed as appropriate.

The number of starting electric fans (20a) and (20b) may be one or three or more may be connected in parallel.

Burner (2), compressor (12), gas turbine (16), starting electric fan (20a), (20b
), a check valve (19), an air passage (17) with an attached air passage (17), etc., and the method of operating the turbo hot air generator does not matter.

The heating load of the burner (2) has decreased to less than the set value during self-blade operation, or the startup electric fan (20a)
To detect that the heating load of the burner (2) has increased beyond the set value during the operation of the gas turbine (20b), appropriate information suitable for the heating object can be used.
), the temperature of the hot air and exhaust gas supplied to the air pressure detector (3
The air suction pressure from 0) may also be used.

The activation and stopping operations of the starting electric fans (20a) and (20b) may be performed manually or automatically by a controller.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a boiler showing an embodiment of the present invention;
FIG. 2 is a diagram of the principle of the boiler, and FIG. 3 is a graph for explaining the operating state of the boiler. (2)...Burner, (12)...Compressor, (16)...Gas turbine, (1
7)...Intake path, (19)...Check valve, (20a), (20b)...Start-up electric fan, (A)...・First heat exchanger, (B)...
...Second heat exchanger.

Claims (1)

[Claims] 1. A compressor (12) that supplies combustion air under pressure to a burner (2) and a gas turbine (16) connected to a high-temperature gas supply path from the burner (2) are interlocked and connected. , an intake path (1) equipped with starting electric fans (20a), (20b) and a check valve (19) is provided on the upstream side of the compressor (12).
7) are connected in parallel, when the heating load of the burner (2) decreases to less than a set value during self-blade operation, the starting electric fan (20a
), (20b), and the electric fan (2
0a), (20b) when the heating load of the burner (2) increases beyond a set value, the starting electric fan (20a), (20b) is stopped. 2. A plurality of the starting electric fans (20a), (20b) are provided, and the starting electric fans (20a), (20b) are provided.
20b), the more the heating load on the burner (2) decreases, the more the starting electric fan (20a), (
20b) The operating method according to claim 1, wherein the number of operating units of 20b) is reduced. 3. The gas turbine (16) is arranged between the first heat exchanger (A) and the second heat exchanger (B) of the boiler, and the heating load of the burner (2) is transferred to the second heat exchanger. The operating method according to claim 1 or 2, wherein the detection is based on vapor pressure measurement of the vessel (B).