JP2015218949A - Burner and boiler system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a burner capable of reducing manufacturing cost and facilitating change to a target combustion amount.SOLUTION: A burner 2 comprises: a first nozzle 21 injecting a fuel with a first fuel injection amount; a second nozzle 22 injecting the fuel with a second fuel injection amount; and a third nozzle 23 injecting the fuel with a third fuel injection amount. At least two out of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount differ from each other. It is thereby possible to change a combustion amount only by switching on or off the fuel injection by each of the first nozzle 21, the second nozzle 22, and the third nozzle 23.

Description

  The present invention relates to a burner and a boiler system.

  Conventionally, some burners are provided with a return flow nozzle as disclosed in JP 2012-193930 A (Patent Document 1). The return flow nozzle is connected to one end of a fuel return line and one end of a fuel return line.

  More specifically, fuel is supplied to the return flow nozzle via a fuel return line, and a part of the fuel is recovered via the fuel return line. The fuel return line is provided with a fuel adjustment valve, and the amount of fuel recovered through the fuel return line is adjusted by the fuel adjustment valve. As a result, the fuel spray amount of the return flow nozzle is changed, and the combustion amount can be changed stepwise.

JP 2012-193930 A

  However, the conventional burner has a problem that the return flow nozzle is expensive and the manufacturing cost becomes high.

  Further, the flow rate of the fuel in the fuel return line is adjusted by the opening of the fuel adjustment valve, but this adjustment is difficult. Therefore, the conventional burner has a problem that it cannot be easily changed to a target combustion amount.

  Therefore, an object of the present invention is to provide a burner that can reduce the manufacturing cost and can easily change the target combustion amount.

In order to solve the above problems, the burner of the present invention is
A burner for evaporating water supplied to a steam boiler,
A first nozzle for injecting fuel at a first fuel injection amount;
A second nozzle for injecting fuel at a second fuel injection amount;
A third nozzle for injecting fuel at a third fuel injection amount,
At least two of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other.

  According to the above configuration, the first nozzle that injects fuel at the first fuel injection amount, the second nozzle that injects fuel at the second fuel injection amount, and the third nozzle that injects fuel at the third fuel injection amount. There is. As a result, the combustion amount can be changed simply by switching on and off the fuel injection of the first nozzle, the second nozzle, and the third nozzle. Therefore, the burner does not have to be provided with a return flow nozzle, so that the manufacturing cost can be reduced.

  Further, the change in the combustion amount by switching on and off the fuel injection of the first nozzle, the second nozzle, and the third nozzle is performed by adjusting the opening of the fuel adjustment valve in the related art (Japanese Patent Laid-Open No. 2012-193930). This is easier than changing the amount of combustion. Therefore, the burner can be easily changed to the target combustion amount.

  Further, since at least two of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other, the number of stages of the combustion amount can be increased. That is, the number of combustion positions can be increased.

  Further, when the fuel injection of the first nozzle, the second nozzle, and the third nozzle is switched on and off, the amount of combustion changes instantaneously. Therefore, the burner can perform so-called high-speed multi-position control.

In one embodiment of the burner,
Each of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount corresponds to a percentage other than 100% of the rated steam generation amount of the steam boiler.

  According to the above embodiment, each of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount corresponds to a percentage other than 100% of the rated steam generation amount of the steam boiler. Can certainly be increased considerably.

In one embodiment of the burner,
By combining the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount, a plurality of fuel injection amounts that are equally spaced and different from each other are obtained.

  According to the above-described embodiment, a plurality of fuel injection amounts with equal intervals and different from each other can be obtained by a combination of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount. Easy to do.

The boiler system of this invention is
A burner of this invention or one embodiment;
A combustion chamber in which fuel from at least one of the first nozzle, the second nozzle, and the third nozzle burns;
A blower for supplying air to the combustion chamber;
A damper for adjusting the amount of air supplied to the combustion chamber;
And a damper opening control unit for controlling the opening of the damper so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber is supplied to the combustion chamber.

  According to the embodiment, when the fuel injections of the first nozzle, the second nozzle, and the third nozzle are turned on and off, the combustion amount changes instantaneously. At this time, the damper opening degree control unit controls the opening degree of the damper so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber is supplied to the combustion chamber. Can respond to changes. Therefore, it is possible to prevent the air supplied to the combustion chamber from becoming excessive or insufficient.

In one embodiment of the boiler system,
Of the first nozzle, the second nozzle, and the third nozzle, the nozzle that is used most frequently is disposed so as to be close to the central axis of the combustion chamber.

  According to the above embodiment, the most frequently used nozzle among the first nozzle, the second nozzle, and the third nozzle is disposed so as to be close to the central axis of the combustion chamber. Distribution unevenness can be reduced.

  The burner according to the present invention includes a first nozzle that injects fuel at a first fuel injection amount, a second nozzle that injects fuel at a second fuel injection amount, and a third nozzle that injects fuel at a third fuel injection amount. Therefore, it is not necessary to provide a return flow nozzle, and the manufacturing cost can be reduced.

  Further, the target combustion amount can be easily changed by switching on and off the fuel injection of the first nozzle, the second nozzle, and the third nozzle.

  Further, since at least two of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other, the number of combustion positions can be increased.

  Further, by switching on and off the fuel injection of the first nozzle, the second nozzle, and the third nozzle, the combustion amount can be instantaneously changed, and so-called high-speed multi-position control can be performed.

  The boiler system of the present invention includes a damper opening degree control unit that controls the opening degree of the damper so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber is supplied to the combustion chamber. It is possible to prevent the supplied air from becoming excessive or insufficient.

FIG. 1 is a schematic view of a main part of a boiler system according to an embodiment of the present invention. FIG. 2 is a control block diagram of the boiler system. FIG. 3 is a schematic view of the first nozzle, the second nozzle, the third nozzle, and the periphery thereof as viewed from above according to an embodiment of the present invention.

  Hereinafter, the burner and boiler system of the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1 is a schematic diagram showing a configuration of a main part of a boiler system including a burner 2 according to an embodiment of the present invention. The first nozzle 21, the second nozzle 22, and the third nozzle 23 are not arranged in a line in the horizontal direction, but in FIG. 1, the first nozzle 21, the second nozzle 22, and the third nozzle 23 are easy to see. Are shown in a line in the horizontal direction. In the following description, “line” is a general term for a flow path, a path, a pipe line, and the like.

  The boiler system includes a once-through steam boiler 1 in which a combustion chamber 1a is provided, a burner 2 for evaporating water supplied to the once-through steam boiler 1, and a first supply air to the combustion chamber 1a. 1 and second blowers 3 and 4 are provided. The once-through steam boiler 1 is an example of a steam boiler. Moreover, the 1st, 2nd air blowers 3 and 4 are examples of an air blower.

  The once-through steam boiler 1 is connected to a water supply tank (not shown) via a water supply line L1. The water supply line L1 is provided with a water supply pump 5 and a check valve 6 in order from the water supply tank side. When the water supply pump 5 is driven, the water in the water supply tank is supplied to the once-through steam boiler 1 via the water supply line L1. In addition, one end of a blow line L2 is connected to the once-through steam boiler 1. This blow line L2 is provided with a concentration blow valve 7, and when the concentration blow valve 7 is opened, water in the once-through steam boiler 1 is drained to the outside through the blow line L2.

  The once-through steam boiler 1 is connected to the steam separator 8 through a steam take-out line L3. One end of a steam supply line L4 is connected to the steam separator 8. Thereby, the steam generated in the once-through steam boiler 1 is supplied to a load device (not shown) through the steam take-out line L3, the steam separator 8 and the steam supply line L4. The supply of steam to the load device is controlled by opening / closing a steam valve 9 provided in the steam supply line L4.

  A blow line L2 between the once-through steam boiler 1 and the concentration blow valve 7 is connected to a steam separator 8 via a precipitation line L5. Thereby, the condensed water produced in the steam separator 8 is guided to the blow line L2 by the precipitation line L5. Further, the water quality of the condensed water in the precipitation line L5 can be measured by the water quality measuring unit 10.

  The boiler system also includes a pressure sensor 11 that detects the pressure in the once-through steam boiler 1.

  The first blower 3 is connected to the once-through steam boiler 1 via the first air supply line L6. A first air amount adjustment damper 12 is provided in the first air supply line L6, and the amount of air supplied from the first blower 3 to the combustion chamber 1a can be adjusted by the first air amount adjustment damper 12. . The first air supply line L6 between the first air amount adjustment damper 12 and the once-through steam boiler 1 is connected to the second blower 4 via the second air supply line L7. The second air supply line L7 is provided with a second air amount adjustment damper 13 so that the amount of air supplied from the second blower 4 to the combustion chamber 1a can be adjusted by the second air amount adjustment damper 13. . The first and second air amount adjustment dampers 12 and 13 are examples of dampers.

  The burner 2 is a burner for evaporating water supplied to the once-through steam boiler 1, and includes a first nozzle 21, a second nozzle 22, and a third nozzle 23. The fuel injected from at least one of the first nozzle 21, the second nozzle 22, and the third nozzle 23 burns in the combustion chamber 1a. The first nozzle 21, the second nozzle 22 and the third nozzle 23 are inserted through an opening 1 b (shown in FIG. 3) provided in the upper part of the once-through steam boiler 1.

  The first nozzle 21 is connected to an oil tank 14 for storing oil (for example, kerosene, A heavy oil) via a first fuel supply line L8. The first fuel supply line L8 is provided with a fuel pump 15 and a first fuel supply valve 16 in order from the oil tank 14 side. When the first fuel supply valve 16 is opened, the first nozzle 21 injects fuel with the first fuel injection amount. This first fuel injection amount corresponds to 20% of the rated steam generation amount of the once-through steam boiler 1.

  One end of a second fuel supply line L9 is connected to the second nozzle 22. The other end of the second fuel supply line L9 is connected to the first fuel supply line L8 between the fuel pump 15 and the first fuel supply valve 16. That is, a part of the fuel flowing from the fuel pump 15 toward the first fuel supply valve 16 can flow into the second fuel supply line L9. A second fuel supply valve 17 is provided in the second fuel supply line L9. When the second fuel supply valve 17 is opened, the second nozzle 22 injects fuel with the second fuel injection amount. This second fuel injection amount corresponds to 40% of the rated steam generation amount of the once-through steam boiler 1. For this reason, the opening area of the injection port of the second nozzle 22 is set to be larger than the opening area of the injection port of the first nozzle 21.

  One end of a third fuel supply line L10 is connected to the third nozzle 23. The other end of the third fuel supply line L10 is connected to a first fuel supply line L8 between the fuel pump 15 and the first fuel supply valve 16 via a part of the second fuel supply line L9. That is, a part of the fuel flowing from the fuel pump 15 toward the first fuel supply valve 16 can flow into the third fuel supply line L10. A third fuel supply valve 18 is provided in the third fuel supply line L10. When the third fuel supply valve 18 is opened, the third nozzle 23 injects fuel with the third fuel injection amount. This third fuel injection amount corresponds to 60% of the rated steam generation amount of the once-through steam boiler 1. For this reason, the opening area of the injection port of the third nozzle 23 is set to be larger than the opening area of the injection port of the second nozzle 22.

  Further, as shown in Table 1 below, 0%, 20%, 40% of the rated steam generation amount of the once-through steam boiler 1 is obtained by a combination of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount. Fuel injection amounts corresponding to%, 60%, 80% and 100% are obtained. In Table 1 below, “O” means that the nozzles in the same row are injecting fuel, while “X” means that the nozzles in the same row are not injecting fuel. Means.

  For example, when a fuel injection amount corresponding to 40% of the rated steam generation amount of the once-through steam boiler 1 is obtained, the second fuel supply valve 17 is opened and the first and third fuel supply valves 16 and 18 are opened. It is closed and fuel is injected only into the second nozzle 22. Further, when a fuel injection amount corresponding to 80% of the rated steam generation amount of the once-through steam boiler 1 is obtained, the first and third fuel supply valves 16 and 18 are opened and the second fuel supply valve 17 is closed. Then, the fuel is injected only into the first and third nozzles 21 and 23. In this way, by controlling the opening and closing of the first fuel supply valve 16, the second fuel supply valve 17, and the third fuel supply valve 18, 0%, 20%, 40% of the rated steam generation amount of the once-through steam boiler 1 is achieved. Fuel injection amounts corresponding to%, 60%, 80% and 100% are obtained. That is, a plurality of fuel injection amounts that are equally spaced and different from each other are obtained.

  Although not shown, the burner 2 also includes an ignition device (not shown) that ignites the fuel injected by the first nozzle 21, the second nozzle 22, or the third nozzle 23.

  FIG. 2 is a control block diagram of the boiler system.

  The boiler system includes a control device 100 including a microcomputer and an input / output circuit. The control device 100 receives signals from the pressure sensor 11, the water quality measurement unit 10, etc., and receives the first fuel supply valve 16, the second fuel supply valve 17, the third fuel supply valve 18, the fuel pump 15, and the water supply pump 5. , The concentration blow valve 7, the first blower 3, the second blower 4, the first air amount adjusting damper 12, the second air amount adjusting damper 13, and the like are controlled.

  Further, the control device 100 controls the opening degree of the first and second air amount adjusting dampers 12 and 13 so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber 1a is supplied to the combustion chamber 1a. A damper opening control unit 100a to be controlled is provided. The damper opening control unit 100a is configured by software.

  FIG. 3 is a schematic view of the first nozzle 21, the second nozzle 22, the third nozzle 23, and the periphery thereof as seen from above.

  The first nozzle 21, the second nozzle 22 and the third nozzle 23 are arranged so as to draw a triangle. More specifically, among the first nozzle 21, the second nozzle 22, and the third nozzle 23, the first nozzle 21 having the highest use frequency is disposed so as to be close to the central axis 50 of the combustion chamber 1 a.

  According to the boiler system configured as described above, the control device 100 controls the opening and closing of the first fuel supply valve 16, the second fuel supply valve 17, and the third fuel supply valve 18, so that the first nozzle 21, the second nozzle 22, and Each fuel injection of the third nozzle 23 is switched on and off. As a result, fuel injection amounts corresponding to 0%, 20%, 40%, 60%, 80%, and 100% of the rated steam generation amount of the once-through steam boiler 1 can be obtained. Therefore, the burner 2 does not need to be provided with a return flow nozzle in order to obtain a plurality of different fuel injection amounts, so that the manufacturing cost can be reduced.

  The change in the combustion amount by switching on and off the fuel injection of the first nozzle 21, the second nozzle 22, and the third nozzle 23 is the opening degree of the conventional fuel adjustment valve (Japanese Patent Laid-Open No. 2012-193930). This is easier than changing the amount of combustion by adjusting. Therefore, the burner 2 can be easily changed to the target combustion amount.

  Further, since the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other, the number of combustion positions can be increased.

  Further, when the fuel injection of the first nozzle 21, the second nozzle 22, and the third nozzle 23 is switched on and off, the amount of combustion changes instantaneously. Therefore, the burner 2 can perform so-called high-speed multi-position control.

  Each of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount is a percentage other than 100% of the rated steam generation amount of the once-through steam boiler 1 (20%, 40%, 60%). Therefore, it is possible to reliably increase the number of combustion positions considerably.

  If the first, second, and third fuel injection amounts correspond to 20%, 40%, and 100% of the rated steam generation amount of the once-through steam boiler 1, it is less than the number of combustion positions in this embodiment. turn into.

  Further, since the fuel injection amount corresponding to 0%, 20%, 40%, 60%, 80%, 100% of the rated steam generation amount of the once-through steam boiler 1 can be obtained, the generated steam pressure can be easily stabilized.

  In addition, when the fuel injection of the first nozzle 21, the second nozzle 22, and the third nozzle 23 is switched on and off, the amount of combustion changes instantaneously. At this time, the damper opening degree control unit 100a controls the opening degree of the damper so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber 1a is supplied to the combustion chamber 1a. Can respond to changes. Therefore, it is possible to prevent the air supplied to the combustion chamber 1a from becoming excessive or insufficient.

  Moreover, since the 1st nozzle 21 with the highest use frequency is arrange | positioned so that it may become close to the central axis 50 of the combustion chamber 1a among the said 1st nozzle 21, the 2nd nozzle 22, and the 3rd nozzle 23, it is combustion. Unevenness of temperature distribution in the chamber 1a can be reduced.

  In the above-described embodiment, the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other, but of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount. Only two may be different from each other. For example, the first fuel injection amount is 20% of the rated steam generation amount of the once-through steam boiler 1, the second fuel injection amount is 40% of the rated steam generation amount of the once-through steam boiler 1, and the third fuel injection amount is You may make it respond | correspond to 40% of the rated steam generation amount of the once-through steam boiler 1. FIG. Also in this case, as shown in Table 2 below, the combination of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount is 0% of the rated steam generation amount of the once-through steam boiler 1, Fuel injection amounts corresponding to 20%, 40%, 60%, 80% and 100% are obtained. The meanings of “◯” and “×” in Table 2 below are the same as the meanings of “◯” and “×” in Table 1 above.

  For example, when a fuel injection amount corresponding to 40% of the rated steam generation amount of the once-through steam boiler 1 is obtained, the second fuel supply valve 17 is opened and the first, third, and the like, as in the above embodiment. The fuel supply valves 16 and 18 are closed, and fuel is injected only into the second nozzle 22. Further, when a fuel injection amount corresponding to 80% of the rated steam generation amount of the once-through steam boiler 1 is obtained, the second and third fuel supply valves 17 and 18 are opened, and the first fuel supply valve 16 is closed. Then, the fuel is injected only into the second and third nozzles 22 and 23.

  In the above embodiment, the burner 2 includes three nozzles, but may include four or more nozzles. For example, when the burner 2 includes four nozzles, one fuel injection amount of the four nozzles is an amount corresponding to 10% of the rated steam generation amount of the once-through steam boiler 1. The other one fuel injection amount of the four nozzles is an amount corresponding to 20% of the rated steam generation amount of the once-through steam boiler 1. The other one fuel injection amount of the four nozzles is an amount corresponding to 30% of the rated steam generation amount of the once-through steam boiler 1. The other one fuel injection amount of the four nozzles is an amount corresponding to 40% of the rated steam generation amount of the once-through steam boiler 1. Even if it does in this way, the effect similar to the said embodiment is obtained.

  In the said embodiment, although the 1st nozzle 21, the 2nd nozzle 22, and the 3rd nozzle 23 injected the oil into the combustion chamber 1a, you may inject a natural gas into the combustion chamber 1a, for example.

  In the above embodiment, the damper opening degree control unit 100a is configured by software, but the damper opening degree control unit 100a may be configured by hardware.

  In the above embodiment, the first nozzle 21, the second nozzle 22, and the third nozzle 23 are not arranged in a line in the horizontal direction, but may be arranged in a line in the horizontal direction.

  In the said embodiment, although this invention was used for the once-through-type steam boiler 1, you may use for steam boilers, such as a water pipe type steam boiler and a furnace tube | pipe smoke pipe type steam boiler.

  Although specific embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. For example, what combined suitably the content as described in the said embodiment is good also as one Embodiment of this invention.

DESCRIPTION OF SYMBOLS 1 1st flow-type steam boiler 1a Combustion chamber 3 1st air blower 4 2nd air blower 21 1st nozzle 22 2nd nozzle 23 3rd nozzle 50 Center axis 100 Control apparatus 100a Damper opening degree control part

Claims (5)

A burner for evaporating water supplied to a steam boiler,
A first nozzle for injecting fuel at a first fuel injection amount;
A second nozzle for injecting fuel at a second fuel injection amount;
A third nozzle for injecting fuel at a third fuel injection amount,
At least two of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount are different from each other. The burner according to claim 1, wherein
Each of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount corresponds to a percentage other than 100% of the rated steam generation amount of the steam boiler. The burner according to claim 1 or 2,
A burner characterized in that a plurality of different fuel injection amounts with equal intervals are obtained by a combination of the first fuel injection amount, the second fuel injection amount, and the third fuel injection amount. The burner according to any one of claims 1 to 3,
A combustion chamber in which fuel from at least one of the first nozzle, the second nozzle, and the third nozzle burns;
A blower for supplying air to the combustion chamber;
A damper for adjusting the amount of air supplied to the combustion chamber;
A boiler system comprising: a damper opening degree control unit that controls the opening degree of the damper so that an amount of air corresponding to the amount of fuel combusted in the combustion chamber is supplied to the combustion chamber. In the boiler system according to claim 4,
A boiler system, wherein a nozzle that is most frequently used among the first nozzle, the second nozzle, and the third nozzle is disposed so as to be close to a central axis of the combustion chamber.

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