JPH0356730Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Field of industrial application] This invention is an ultra-wide range oil that enables stable combustion at ultra-low loads in relatively large boilers equipped with multiple burners. It concerns burners.

[Prior Art] Conventionally, in general boilers, the number of burners in operation is increased or decreased in accordance with load fluctuations, and the combustion amount is changed in accordance with the required amount of steam.

A commonly used oil burner is shown in FIG. In this oil burner, combustion air enters from a, passes through a throat part b, and forms a flame by a primary swirler c. And in the case of multiple equipped burners,
When extinguishing the fire, a slide damper e fixed to a sliding shaft d is closed to cut off air into the boiler. On the other hand, when burning oil, a sufficient air velocity is required at the throat. By lowering combustion, the amount of air required is proportionally reduced. Therefore, the flow velocity also decreases proportionally, making it impossible to achieve stable combustion and reducing the combustion rate to 1/7 to 1/1 of the rated load combustion.
0 is the minimum combustion limit, which is 1/15 to 1/15 of the rated evaporation amount.
1/20 is the minimum limit, and stable combustion is impossible under conditions below that, resulting in large losses in fuel and power costs.

[The problem that the idea attempts to solve]

However, in conventional oil burners, because the throat is constant (one throat), the minimum combustion amount for achieving stable combustion is inevitably limited. In addition, looking at the recent status of ship operations in the shipping industry, turbine ships equipped with main boilers are being kept in a "semi-anchored state" such as waiting at sea or anchoring for extended periods due to port conditions and declining demand for crude oil. During this period, only a very small amount of steam, 1/60 to 1/80 of the rated evaporation amount, is required.

In response to the above requirements, conventional burners have a stable combustion limit and cannot reduce the load to the above-mentioned amount of steam. In the case of actual ships, the current limit is 1/20 of the rated evaporation amount, so excess steam is released.

Therefore, not only is there a loss in terms of fuel, but the fans, pumps, heaters, etc. operate with a large amount of power for the rated capacity even at the lowest combustion load, so there are disadvantages such as a large loss in power noise.

The present invention was made with the aim of eliminating this drawback.

[Means to solve the problem]

In order to achieve the above object, this invention uses one of the multiple oil burners installed in a boiler, etc. as an ultra-wide range oil burner, and this ultra-wide range oil burner has a secondary throat fixed at the tip. Insert the primary sleeve, which has two air supply ports connected individually for small and large volumes, into the secondary sleeve, and expand the tip of the primary sleeve into a flat shape to open the primary sleeve. A slide that forms a throat, provides a primary swirler and an atomizer within the primary throat, provides a secondary swirler around the outer periphery of the primary throat, and independently adjusts the amount of air supplied to the air passages to the primary and secondary sleeves. A damper is installed so that the air supplied to each sleeve can be freely adjusted, and the damper is installed in a small-capacity air supply duct that is connected to a wind box installed at the rear end of the primary sleeve and can be opened and closed. The gist of the invention is to provide an oil amount regulating valve in the fuel supply pipe that supplies the fuel to the burner nozzle.

〔Example〕

The present invention will be explained below based on the embodiments shown in FIG. 2 and the following drawings.

Figure 2 is a cross-sectional view of the ultra-wide range oil burner used in the present invention. Generally, when multiple oil burners are installed in a boiler etc., one of the oil burners is used as the ultra-wide range oil burner of the present invention. It is something to do.

Next, a description will be given based on FIG. 2. A secondary sleeve 2 is provided on the back side of a secondary throat 1 protruding into a boiler, etc., and a primary sleeve 6 is inserted into this secondary sleeve 2, and a secondary sleeve is inserted into the passage between the primary sleeve 6 and the secondary sleeve 2. Combustion air is supplied from an air intake port 3 formed on the outer periphery of the rear end of the secondary sleeve, and a primary throat 7 widened in a flare shape is connected to the tip of the primary sleeve 6. A secondary swirler 11 is integrally formed on the outer periphery of the throat, and an air intake port 8 is formed on the outer periphery of the rear end of the primary sleeve 6, and air from the air intake port 8 flows inside the primary sleeve 6. .

Furthermore, slide dampers 4 and 9 are disposed in the air intake ports 3 and 8, respectively, and the slide dampers 4 and 9 are slid by sliding shafts 5 and 10 protruding from the air intake ports 3 and 8, respectively. Open and close intake ports 3 and 8. Furthermore, a wind box 16 is formed at the rear end of the primary sleeve 6, and a duct 14 is provided protruding from the wind box independently of the air intake port 8, and the air is passed through the small capacity air supply duct. A small volume of air during load combustion is supplied into the primary sleeve 6. A damper 15 that opens and closes is provided in the duct 14, and a primary swirler 1 is provided at the tip of the primary sleeve 6.
2 and a burner nozzle 13 are provided.

FIG. 5 shows an example of implementing the ultra-wide range oil burner of the present invention, which is usually used in combination with a general oil burner. In the figure, A is a conventional type oil burner, and B is an ultra-wide range burner of the present invention. Boiler B ₀ is equipped with a plurality of oil burners A, at least one of which is installed as an ultra-wide range oil burner B in a common wind box 17 protruding from the boiler surface, and this common wind box 17 has a large capacity. A large-capacity blower 18 is connected to supply the air necessary for combustion at the load set in , and a fuel supply circuit C that supplies fuel oil to the oil burners A and B and sprays the fuel oil. A steam circuit D for supplying a medium such as steam is arranged as shown in FIG.
These two circuits C and D are divided into regular system circuits C1 and D1, which cause combustion at a regular set load, and ultra-low load system circuits C2 and D2.

The fuel oil from the oil tank 19 is transferred to the strainer 20 during load combustion, which is set using the regular system circuit.
The pump 21 pressurizes the heater 22.
The oil is heated in
Fuel oil is supplied to each burner from this header 25, and fuel oil is uniformly supplied to each burner.
Combustion is performed under the same conditions, but the air-fuel ratio is changed to oil flow adjustment valve 2.
4 and a fan damper 18a provided on the blower 18. On the other hand, steam (atomizing water vapor or air) is supplied to a steam header 27 via a pressure regulating valve 26, and is supplied from this header 27 to each oil burner to spray oil in each burner.

During this normal operation, the air intake ports 3 and 8 are fully opened by sliding the slide dampers 4 and 9, the large-capacity fan 18 is driven, and each device connected to the circuits C1 and D1 is operated, and the fuel oil , steam is supplied, but the circuits C2 and D2 are closed. At the same time, the blower 28 is stopped and the damper 15 is closed. When performing ultra-low-load combustion, large-capacity auxiliary equipment is stopped and switched to drive small-capacity auxiliary equipment. Therefore, the circuit C1, D1 is closed, the circuit C2, D2 is opened, and the circuit C
2. Fuel oil and steam from D2 to oil burner B
Supplied only to At this time, the blower 18 is stopped, the dampers 4 and 9 of the oil burner B are closed, the damper 15 is opened, and a small volume of air is supplied from the duct 14 and the wind box 16 into the primary throat by the small volume fan 28. . In this case oil burner B
Since combustion occurs only through the primary throat of the burner, the air passage is small and sufficient air flow velocity is ensured, resulting in stable and complete combustion even at extremely low loads compared to conventional oil burners. In the case of this ultra-low load combustion, the oil discharged from the oil tank 19 is supplied to the burner B of the present invention through small equipment, a strainer 29, a pump 30, a heater 31, and an oil amount adjustment valve 32. On the other hand, steam (air) is supplied to the burner B via the pressure regulating valve 33 and the electromagnetic valve 34, and in this way, switching from normal use to extremely low load can be easily performed by simply switching the valve and changing the air passage. In addition, in this ultra-low load combustion, Hi/Lo (ON/
OFF) or can be followed by proportional control. Further, the air-fuel ratio is controlled by the oil amount adjusting valve 32 and the air damper 15.

Figure 3 shows an example of the combustion load factor and excess air coefficient of the conventional burner and the burner of the present invention.As is clear from the figure, the conventional burner has a combustion range of 100% to 15%, while the burner of the present invention has a combustion range of 100% to 15%. Expanded from 100% to 5%.

[Effect of idea]

Therefore, compared to conventional burners, the present invention enables safe and complete combustion even at ultra-low load combustion, and is effective as an energy-saving measure.

[Brief explanation of drawings]

Figure 1 is a sectional view of a conventional burner, Figure 2 is a sectional view of the burner of the present invention, Figures 3 and 4 are graphs showing the characteristics of the burner of the present invention, Figure 5 is an example, and Figure 6 is a sectional view of the burner of the present invention. 6 is a circuit diagram of FIG. 5; FIG. 1...Secondary throat, 2...Secondary sleeve,
3, 8... Air intake port, 4, 9... Slide damper, 5, 10... Sliding shaft, 6... Primary sleeve, 7... Primary throat, 11... Secondary swirler,
12...Primary swirler, 13...Burna nozzle, 1
4... Duct, 15... Damper, 17... Common wind box, 18, 28... Blower, 19... Oil tank, 20, 23, 29... Strainer, 21,
30... Pump, 22, 31... Heater, 2
4, 32... Oil amount adjustment valve, 25... Oil header, 26, 33... Pressure adjustment valve, 27... Steam header, A, B... Oil burner.

Claims (1)

[Scope of utility model registration request] Insert a primary sleeve with two air supply ports connected individually for small and large volumes into the secondary sleeve with a secondary throat fixed to the tip, and then push the tip of the primary sleeve loosely. The primary throat is expanded to form a primary throat, and a primary swirler and an atomizer are provided within this primary throat, and a secondary swirler is provided around the outer periphery of the primary throat, and air passages to the primary and secondary sleeves are provided independently. A slide damper is installed to adjust the amount of air supplied, making it possible to freely adjust the air supplied to each sleeve.In addition, a small volume air supply duct is installed that is connected to the wind box installed at the rear end of the primary sleeve. An oil burner for ultra-wide range use, characterized in that a damper is provided so that the fuel can be opened and closed freely, and an oil amount adjustment valve is provided in the fuel supply pipe that supplies the burner nozzle.