JP7432359B2 - Shock wave soot blower and its operating method - Google Patents

Description

The present invention relates to a shock wave soot blower and a method of operating the same.

BACKGROUND ART Shock wave soot blowers have conventionally been used in devices such as boilers to remove dust adhering to equipment surfaces (for example, surfaces of superheaters) within the device (see, for example, Patent Document 1). This shock wave soot blower is configured to generate shock waves by burning a mixture containing fuel gas and oxidant gas, and to emit the shock waves into the internal space of the device. This shock wave removes dust from the equipment surfaces within the device.

In general, a shock wave soot blower includes a combustion chamber that mixes and burns fuel gas and oxidizing gas, a fuel gas storage tank that stores each of the fuel gas and oxidizing gas to be supplied to the combustion chamber, and Conventionally, gas is supplied to the combustion chamber by filling each storage tank with fuel gas and oxidant gas until a predetermined set pressure value is reached, and then filling each storage tank with gas. This is done by transferring gas to the combustion chamber for a predetermined period of time (sufficient time for the pressure in each storage tank to reach equilibrium with the pressure in the combustion chamber).

Japanese Patent Application Publication No. 2005-172418

In a shock wave type soot blower, the impact force of the output shock wave is determined by the pressure inside the combustion chamber. Therefore, in a shock wave type soot blower operated as described above, the range of shock wave intensity that can be output by design is mainly due to the fuel gas storage tank and oxidizer. It will be determined by the volume of the agent storage tank. In that case, if a lower output becomes sufficient due to a change in the scale of the equipment in which the soot blower is installed or a change in operating conditions, running costs will be wasted.

SUMMARY OF THE INVENTION Therefore, in order to solve the above-mentioned problems, an object of the present invention is to provide a shock wave soot blower and its operation that can easily optimize running costs by making it possible to flexibly change the operable output range. The purpose is to provide a method.

In order to achieve the above object, the shock wave soot blower according to the present invention has the following features:
A shock wave soot blower that outputs a shock wave by burning a mixture of fuel gas and oxidizing gas,
a combustion chamber that mixes and burns the fuel gas and the oxidant gas;
a soot blower main body having a discharge nozzle that outputs a shock wave by discharging combustion gas generated in the combustion chamber;
an opening/closing mechanism provided in the soot blower main body and configured to close the inlet of the discharge nozzle using a pressurized gas, which is a nonflammable gas, before the start of combustion, and to open the inlet of the discharge nozzle after the start of combustion;
a fuel supply source that supplies the fuel gas;
an oxidizing agent supply source that supplies the oxidizing gas;
a fuel storage tank provided between the fuel supply source and the combustion chamber and storing the fuel gas;
an oxidant storage tank that is provided between the oxidant supply source and the combustion chamber and stores the oxidant gas;
an output adjustment gas supply path that supplies the pressurized gas as an output adjustment gas from a pressurized gas supply source that supplies the pressurized gas to the opening/closing mechanism to at least one of the fuel storage tank and the oxidizer storage tank;
Equipped with.

Furthermore, the method of operating the shock wave soot blower according to the present invention includes:
supplying the fuel gas from the fuel supply source to the fuel storage tank until a predetermined set pressure value is reached;
supplying the oxidant gas from the oxidant supply source to the oxidant storage tank until a predetermined set pressure value is reached;
supplying the pressurized gas from the pressurized gas supply source to at least one of the fuel storage tank and the oxidizer storage tank via the output adjustment gas supply path until a predetermined set pressure value is reached;
After gas supply to the fuel storage tank and gas supply to the oxidizer storage tank are completed, the gas stored in each storage tank is transferred from the fuel gas storage tank and the oxidizer storage tank to the combustion chamber for a predetermined period of time. a process of supplying
Equipped with.

According to this configuration, the output of the shock wave soot blower can be reduced by using the pressurized gas, which is a nonflammable gas that has been conventionally used to operate the shock wave soot blower. Therefore, even if a lower output is required due to a change in the scale of the equipment, etc., the soot blower can be easily used at an appropriate running cost without significantly changing the specifications.

In the shock wave soot blower according to an embodiment of the present invention, the shock wave soot blower further includes an impact force measuring device that measures the impact force output from the shock wave soot blower; The oxidizing agent storage tank may further include a control device that controls the supply amount of the pressurized gas to at least one of the oxidizing agent storage tanks.

Furthermore, the method for operating the shock wave soot blower according to the above embodiment may include a step of determining the supply amount of the pressurized gas based on the measured value of the impact force measuring device.

With this configuration, the output of the shock wave soot blower can be directly measured and fed back, making it possible to determine the amount of pressurized gas supplied to each storage tank with high accuracy, and efficiently optimizing running costs. Can be done.

The shock wave soot blower according to an embodiment of the present invention may further include a purge gas supply path for supplying the pressurized gas as a purge gas from the pressurized gas supply source to the discharge nozzle. According to this configuration, by using the inexpensive pressurized gas that has traditionally been used to operate shock wave soot blowers for purging, there is no need to separately install and operate equipment such as a compressor exclusively for purging. Costs can be suppressed.

As described above, according to the present invention, it is possible to flexibly change the operable output range of a shock wave soot blower, and running costs can be easily optimized.

1 is a block diagram showing a schematic configuration of a shock wave soot blower system according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the structure and operation of the soot blower used in the shock wave soot blower system of FIG. 1 and its operation before starting combustion. FIG. 2 is a cross-sectional view showing the structure of the soot blower used in the shock wave soot blower system of FIG. 1 and its operation after combustion starts.

Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments.

FIG. 1 shows a schematic configuration of a shock wave soot blower (hereinafter simply referred to as "soot blower") 1 according to an embodiment of the present invention. The soot blower 1 is installed, for example, in a boiler that uses exhaust heat from a waste incinerator as a heat source, and is used to remove dust attached to devices such as a superheater in the boiler by using shock waves SP. However, the use of the soot blower 1 is not limited to this.

The soot blower 1 combusts a mixture of fuel gas F and oxidizing gas O, and outputs a shock wave SP by discharging combustion gas B generated thereby. In this embodiment, methane gas is used as the fuel gas F, and oxygen gas is used as the oxidant gas O. However, the fuel gas F and the oxidant gas O are not limited to these.

The soot blower 1 includes a combustion chamber 3 and a soot blower main body 5 integrated with the combustion chamber 3. The soot blower main body 5 is provided with a discharge nozzle 7 that discharges the combustion gas B generated in the combustion chamber 3. The soot blower 1 further includes a fuel tank 9 as a fuel supply source and an oxidizer tank 11 as an oxidizer supply source. A fuel storage tank 15 is provided between the fuel tank 9 and the combustion chamber 3, that is, in the middle of the fuel supply path 13 that supplies the fuel gas F from the fuel tank 9 to the combustion chamber 3. An oxidant storage tank 19 is provided between the oxidant tank 11 and the combustion chamber 3, that is, in the middle of the oxidant supply path 17 that supplies the oxidant gas O from the oxidant tank 11 to the combustion chamber 3. In the following description, for convenience, the portion of the fuel supply path 13 from the fuel tank 9 to the fuel storage tank 15 will be referred to as the first fuel supply path 13a, and the portion from the fuel storage tank 15 to the combustion chamber 3 will be referred to as the first fuel supply path 13a. 2 fuel supply path 13b. Similarly, the part of the oxidizer supply path 17 from the oxidizer tank 11 to the oxidizer storage tank 19 is called the first oxidizer supply path 17a, and the part from the oxidizer storage tank 19 to the combustion chamber 3 is called the first oxidizer supply path 17a. It is called a second oxidizing agent supply path 17b.

The first fuel supply passage 13a and the second fuel supply passage 13b are provided with a first fuel supply passage opening/closing valve 21 and a second fuel supply passage opening/closing valve 23, respectively. A first oxidizing agent supply passage opening/closing valve 25 and a second oxidizing agent supply passage opening/closing valve 27 are provided in the two oxidizing agent supply passages 17b, respectively. The fuel storage tank 15 and the oxidizer storage tank 19 are provided with a fuel storage tank pressure measurement device 29 and an oxidizer storage tank pressure measurement device 31 that measure the pressure inside each storage tank 15, 19, respectively.

Here, the structure of the soot blower 1 and the operating principle for generating the shock wave SP will be explained with reference to FIGS. 2A and 2B. Specifically, the combustion chamber 3 provided integrally with the soot blower body 5 includes a pair of main combustion chambers 35, 35 extending from both sides of the soot blower body 5 perpendicularly to the discharge direction of the combustion gas B; It has a pre-combustion chamber 37 located between the combustion chambers 35, 35. A fuel supply passage 13 and an oxidizer supply passage 17 are connected to the pair of main combustion chambers 35, 35. A cylinder 39 is provided between the pair of main combustion chambers 35, 35. Inside the cylinder 39, a piston 41 is slidably provided on the inner circumferential wall of the cylinder 39. A discharge port 43 that forms the inlet of the discharge nozzle 7 is provided in a portion of the soot blower body 5 that faces the piston 41 . That is, the piston 41 is provided so as to be movable in the direction in which the combustion gas B is discharged.

A head 41 a provided at the rear end of the piston 41 (an end opposite to the discharge port 43 ) is in sliding contact with the inner circumferential wall of the cylinder 39 . A space between the head 41a of the piston 41 and the rear inner wall of the cylinder 39 is filled with a pressurizing gas P for pressing the piston 41 forward. As the pressurized gas P, a nonflammable gas (nitrogen gas in this example) is used. A portion of the inner space of the cylinder 39 in front of the head 41a of the piston 41 forms the preliminary combustion chamber 37. In the state shown in FIG. 2A before the start of combustion, the piston 41 closes the discharge port 43 due to the pressure of the pressurized gas P.

An ignition device 45 is provided in the preliminary combustion chamber 37. The mixed gas of fuel gas F and oxidizing gas O introduced into the main combustion chamber 35 and flowing into the pre-combustion chamber 37 as shown in FIG. 2B is ignited by the ignition device 45, and the mixture is combusted in the pre-combustion chamber 37. When combustion starts, the piston 41 is pushed back rearward due to the pressure increase in the pre-combustion chamber 37, and the discharge port 43 is opened. While the discharge port 43 is open, combustion of the air-fuel mixture spreads from the pre-combustion chamber 37 to the entire main combustion chamber 35, and the combustion gas B generated thereby is discharged from the discharge nozzle 7. A shock wave SP is output by this discharged combustion gas B.

Thus, in this embodiment, the piston 41 provided in the combustion chamber 3 and the pressurized gas P close the discharge port 43 of the combustion gas B before the start of combustion, and open the discharge port 43 after the start of combustion. An opening/closing mechanism 47 is constructed.

The soot blower 1 includes a pressurized gas tank 49 that is a pressurized gas supply source that supplies the pressurized gas to the opening/closing mechanism 47 of the soot blower main body 5. The pressurized gas P in the pressurized gas tank 49 is supplied to the soot blower main body 5 via the pressurized gas supply path 51. The soot blower 1 further includes an output adjustment gas supply path 53 that supplies pressurized gas P as an output adjustment gas from the pressurized gas tank 49 to the fuel storage tank 15 and oxidizer storage tank 19. In the following description, the supply path from the pressurized gas tank 49 to the fuel storage tank 15 will be referred to as the "first output adjustment gas supply path 53A," and the supply path from the pressurized gas tank 49 to the oxidizer storage tank 19 will be referred to as the "second output adjustment gas supply path 53A." It is called "gas supply path 53B".

In the illustrated example, the first output adjustment gas supply path 53A is provided as a path that branches from the middle of the pressurized gas supply path 51 and connects to the first fuel supply path 13a. Similarly, the second output adjustment gas supply path 53B is provided as a path that branches off from the middle of the pressurized gas supply path 51 and connects to the first oxidizer supply path 17a. However, both output adjustment gas supply paths 53A and 53B may be provided so as to directly connect the fuel tank 9 and oxidizer tank 11 to the fuel storage tank 15 and oxidizer storage tank 19, respectively. The first output adjustment gas supply path 53A and the second output adjustment gas supply path 53B are provided with a first output adjustment gas supply path opening/closing valve 55 and a second output adjustment gas supply path opening/closing valve 57, respectively.

A method of operating the soot blower 1 configured in this way will be explained. First, a case will be described in which the capacity of each storage tank 15, 19 is utilized to the maximum to output an impact force in the maximum range designed for the soot blower 1 (hereinafter referred to as "high output mode"). First, the first fuel supply passage opening/closing valve 21 and the first oxidizing agent supply passage opening/closing valve 25 are opened, and the fuel gas F and fill only with oxidant gas O. Next, the first fuel supply passage opening/closing valve 21 and the first oxidizing agent supply passage opening/closing valve 25 are closed, the second fuel supply passage opening/closing valve 23 and the second oxidizing agent supply passage opening/closing valve 27 are opened, and the fuel gas F and Oxidizing gas O is supplied to the combustion chamber 3. When the fuel gas F and the oxidant gas O are supplied to the combustion chamber 3, the second fuel supply passage on-off valve 23 and the second oxidant supply passage on-off valve 27 are operated for a predetermined period of time (the pressure in each storage tank 15, 19 is The pressure inside the combustion chamber 3 is set to be opened only for a sufficient period of time for the pressure within the combustion chamber 3 to reach equilibrium. After the supply of the fuel gas F and the oxidizing gas O to the combustion chamber 3 is completed, the soot blower main body 5 outputs a shock wave SP.

Next, a case will be described in which the soot blower 1 is made to output an impact force below the designed maximum range by using the pressurized gas P (hereinafter referred to as "low output mode"). In low output mode, by adding a nonflammable pressurized gas P that does not involve combustion to a mixed gas of fuel gas F and oxidizing gas O, the shock caused by combustion is reduced while maintaining the apparent pressure of the mixed gas. Reduce force.

Specifically, first, the first fuel supply passage opening/closing valve 21 and the first oxidizing agent supply passage opening/closing valve 25 are opened, and the intermediate pressure values set in each of the fuel storage tank 15 and the oxidizing agent storage tank 19 are set respectively. Only the fuel gas F and the oxidant gas O are supplied until the Next, the first fuel supply passage opening/closing valve 21 and the first oxidizing agent supply passage opening/closing valve 25 are closed, the first output regulating gas supply passage opening/closing valve 55 and the second output regulating gas supply passage opening/closing valve 57 are opened, and the fuel Each of the storage tank 15 and the oxidizer storage tank 19 is filled with pressurized gas P until the respective set final pressure values are reached. Note that in supplying gas to each storage tank 15, 19, the pressurized gas P may be supplied first, and the fuel gas and the oxidizing gas may be supplied thereafter. The procedure after the filling of each stored gas is completed in this way is the same as in the high output mode.

Note that the output adjustment gas supply path 53 does not need to be provided on both the fuel gas side and the oxidant gas side, and may be provided only on either one.

The soot blower 1 according to the present embodiment also includes an impact force measuring device 61 that is installed in an installation area of target equipment from which dust is to be removed by the soot blower 1 and measures the impact force output from the soot blower 1; The control device 63 controls the amount of pressurized gas P supplied to the fuel storage tank 15 and the oxidizer storage tank 19 based on the measured values of the fuel storage tank 61. In this embodiment, depending on the scale of the equipment in which the soot blower 1 is installed, the operating status of the equipment, etc., it is determined whether to select a high output mode or a low output mode, and when operating in the low output mode. The extent to which the output is reduced (that is, the amount of pressurized gas P supplied) is determined based on the measured value by the impact force measuring device 61. As the impact force measuring device 61, for example, a pressure sensor or a strain gauge can be used. The impact force measuring device 61 is attached to, for example, a wall surface in an installation area or a target device.

When performing the above control, for example, the correspondence between the amount of pressurized gas P supplied to each storage tank 15, 19 and the obtained impact force is prepared as a map or function through a test run in advance, and the The supply amount of gas P is determined based on such a map or function.

Note that it is not essential to determine the output of the soot blower 1 based on the measured value by the impact force measuring device 61. For example, when the soot blower 1 is used to remove dust from a heat exchanger of a boiler, the supply amount of the pressurized gas P may be determined based on the relationship with the heat absorption amount of the boiler.

In this embodiment, the soot blower 1 further includes a purge gas supply path 65 that supplies purge gas to the discharge nozzle 7. The purge gas supply path 65 supplies the pressurized gas P from the pressurized gas supply source to the discharge nozzle 7 when the equipment in which the soot blower 1 is installed is stopped. In the illustrated example, the purge gas supply path 65 is provided as a path that branches off from the middle of the pressurized gas supply path 51. The purge gas supply path is provided with an on-off valve (not shown).

Note that it is not essential to configure the purge gas supply path 65 as a path for supplying the pressurized gas P from the pressurized gas tank 49 to the discharge nozzle 7. For example, air may be supplied to the discharge nozzle 7 as a purge gas from a compressor separately provided for purging. However, it is generally preferable to constantly supply purge gas while the equipment in which the soot blower 1 is installed is stopped. Therefore, by using the inexpensive pressurized gas P that has conventionally been used to operate the shock wave soot blower 1 for purging, there is no need to separately install and operate equipment such as a dedicated compressor for purging, further reducing running costs. Can be suppressed.

According to the shock wave soot blower 1 and the operating method thereof according to the present embodiment described above, the output of the soot blower is reduced by using the pressurized gas P, which is a nonflammable gas conventionally used to operate the soot blower 1. be able to. Therefore, even if a lower output is required due to a change in the scale of the equipment, etc., the soot blower 1 can be easily used at an appropriate running cost without significantly changing the specifications.

As mentioned above, the preferred embodiments of the present invention have been described with reference to the drawings, but various additions, changes, or deletions can be made without departing from the spirit of the present invention. Therefore, such materials are also included within the scope of the present invention.

Although not included in the scope of the present invention, the soot blower 1 according to the embodiment described above may not include the output adjustment gas supply path 53 and may include the purge gas supply path 65 as an essential component. Even with the soot blower 1 having such a configuration, there is no need to separately provide and operate equipment such as a compressor exclusively for purge, and it is possible to obtain the effect that running costs can be suppressed.

1 Shock wave soot blower 3 Combustion chamber 5 Soot blower body 7 Discharge nozzle 9 Fuel tank (fuel supply source)
11 Oxidizing agent tank (oxidizing agent supply source)
15 Fuel storage tank 19 Oxidizer storage tank 47 Opening/closing mechanism 49 Pressure gas tank (pressure gas supply source)
53 Output adjustment gas supply path 61 Impact force measuring device 63 Control device B Combustion gas F Fuel gas O Oxidizing gas SP Shock wave

Claims (5)

A shock wave soot blower that outputs a shock wave by burning a mixture of fuel gas and oxidizing gas,
a combustion chamber that mixes and burns the fuel gas and the oxidant gas;
a soot blower main body having a discharge nozzle that outputs a shock wave by discharging combustion gas generated in the combustion chamber;
an opening/closing mechanism provided in the soot blower main body and configured to close the inlet of the discharge nozzle using a pressurized gas, which is a nonflammable gas, before the start of combustion, and to open the inlet of the discharge nozzle after the start of combustion;
a fuel supply source that supplies the fuel gas;
an oxidizing agent supply source that supplies the oxidizing gas;
a fuel storage tank provided between the fuel supply source and the combustion chamber and storing the fuel gas;
an oxidant storage tank that is provided between the oxidant supply source and the combustion chamber and stores the oxidant gas;
an output adjustment gas supply path that supplies the pressurized gas as an output adjustment gas from a pressurized gas supply source that supplies the pressurized gas to the opening/closing mechanism to at least one of the fuel storage tank and the oxidizer storage tank;
A shock wave soot blower equipped with The shock wave soot blower according to claim 1, further comprising:
an impact force measuring device that measures the impact force output from the shock wave soot blower;
a control device that controls the amount of pressurized gas supplied to at least one of the fuel storage tank and the oxidizer storage tank based on the measured value of the impact force measuring device;
Shock wave type soot blower. The shock wave soot blower according to claim 1 or 2, further comprising:
A shock wave soot blower includes a purge gas supply path that supplies the pressurized gas as a purge gas from the pressurized gas supply source to the discharge nozzle. A method of operating the soot blower according to claim 1 , comprising:
supplying the fuel gas from the fuel supply source to the fuel storage tank until a predetermined set pressure value is reached;
supplying the oxidant gas from the oxidant supply source to the oxidant storage tank until a predetermined set pressure value is reached;
supplying the pressurized gas from the pressurized gas supply source to at least one of the fuel storage tank and the oxidizer storage tank via the output adjustment gas supply path until a predetermined set pressure value is reached;
After the gas supply to the fuel storage tank and the gas supply to the oxidizer storage tank are completed, the gas stored in each storage tank is transferred from the fuel storage tank and the oxidizer storage tank to the combustion chamber for a predetermined period of time. the process of supplying;
How to operate a shock wave soot blower equipped with In the operating method according to claim 4,
A method for operating a shock wave soot blower, comprising a step of determining the predetermined set pressure value of the pressurized gas based on a measurement value of an impact force measuring device that measures the impact force output from the shock wave soot blower.

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