JP2009174723A - Combustion burner and burner unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combustion burner capable of stably burning water-oil mixed fuel. <P>SOLUTION: The water-oil mixed fuel pressurized to prescribed pressure is heated by a heating coil 23, and injected to a combustion chamber 22 by a fuel injection nozzle 57. Combustion air is supplied to one end of an air passage pipe 52 by a blower 7, straightened by a straightening vane 54 in the air passage pipe 52, and then supplied to the combustion chamber 22 from a supply opening 52a while forming a swirl flow by a swirl vane 53. The water-oil mixed fuel and the combustion air are sufficiently mixed by the swirl flow, and the density of combustion air in the combustion air 22 is increased by the swirl flow, and thus the water-oil mixed fuel is stably and completely burned. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a combustion burner and a burner unit that use a liquid obtained by mixing water and oil as fuel.

  Conventionally, as a combustion burner for burning a liquid obtained by mixing water and oil (hereinafter referred to as a water-oil mixed fuel), a water-oil mixed fuel pressurized to a predetermined pressure is disposed on the outer peripheral side of a cylindrical combustion chamber. There is one configured to flow through a spiral heat exchange pipe heated to be injected into a combustion chamber and burned by a fuel injection nozzle disposed at one end of the combustion chamber (see, for example, Patent Document 1). This combustion burner uses a water / oil mixed fuel to reduce the emission of harmful substances such as nitrogen oxides and sulfur oxides compared to the case of using only oil fuel.

  The conventional combustion burner has the following structure. That is, a cylindrical air passage pipe is fixed to one end of the combustion chamber, and a fuel supply pipe connected to the heat exchange pipe extends from one end to the other end in the air passage pipe. The fuel injection nozzle is fixed to the tip of the fuel supply pipe located at the connection between the other end of the air passage pipe and the combustion chamber. An air supply pipe to which combustion air is supplied by a blower is connected in the vicinity of one end of the air passage pipe. In the air passage pipe, rectifying blades are respectively arranged at two locations on the downstream side of the connection portion with the air supply pipe and in the vicinity of the other end. The two rectifying vanes have substantially the same shape and are fitted to the outer peripheral surface of the fuel supply pipe, and have a plurality of blades extending radially in the radial direction of the air passage pipe. The blade of the rectifying blade has an elongated rectangular shape whose radial dimension is larger than the axial dimension.

The combustion burner supplies combustion air from the blower through the air supply pipe to the vicinity of one end of the air passage pipe, and rectifies the combustion air with two rectifying blades in the air passage pipe, thereby generating an air vortex. Instead, the combustion air is blown out from the other end of the air passage tube into the combustion chamber.
JP 2002-13705 A

  However, the conventional combustion burner has a problem that the flow of combustion air in the combustion chamber is difficult to stabilize, and the combustion state of the water-oil mixed fuel is difficult to stabilize. When the combustion state of the water / oil mixed fuel becomes unstable, the temperature of the combustion chamber is difficult to reach a sufficiently high temperature, so that the water / oil mixed fuel is not sufficiently heated by the heat exchange pipe, and the combustion state of the water / oil mixed fuel is not improved. It will be worse. In the worst case, the deterioration of the combustion state causes the inconvenience of stopping the combustion operation of the combustion burner. In addition, when the combustion state of the water / oil mixed fuel becomes unstable, incomplete combustion occurs, resulting in inconvenience that harmful substances such as carbon monoxide and dust remain in the combustion gas.

  Then, the subject of this invention is providing the combustion burner which can burn a water-oil mixed fuel stably.

In order to solve the above problem, the combustion burner of the present invention is a combustion burner for burning a water-oil mixed fuel obtained by mixing water and oil,
A combustion chamber;
A fuel heating unit that is supplied with a water-oil mixed fuel pressurized to a predetermined pressure and heats the water-oil mixed fuel with the heat of the combustion chamber;
A combustion air outlet provided at one end of the combustion chamber;
A fuel injection nozzle disposed at the center of the combustion air outlet and injecting the water-oil mixed fuel heated by the fuel heating unit toward the other end of the combustion chamber;
An air passage pipe having the other end connected to the combustion air outlet and supplied with the combustion air at one end, a rectifying blade disposed in the air passage pipe to rectify the combustion air, and an air passage pipe in the air passage pipe A combustion air supply unit having a swirl vane that is disposed on the other end side of the rectifying vane and forms a swirling flow of the combustion air.

  According to the above configuration, the water / oil mixed fuel pressurized to a predetermined pressure and supplied to the fuel heating unit is heated by the fuel heating unit and then injected from the fuel injection nozzle toward the other end of the combustion chamber. Is done. On the other hand, the combustion air supplied to one end of the air passage pipe of the combustion air supply unit is rectified by the rectifying blade in the air passage pipe, and then a swirling flow is formed by the swirling blade. The combustion air in which the swirl flow is formed in the combustion air supply unit is blown out from the blowout port at the other end to form a swirl flow in the combustion chamber. Here, the water-oil mixed fuel injected from the fuel injection nozzle disposed in the center of the outlet is sufficiently mixed with the combustion air by the swirl flow and discharged into the combustion chamber. In addition, the swirling flow of combustion air is formed in the combustion chamber, so that the residence time of the combustion air in the combustion chamber is increased compared to the case where a linear flow of combustion air is formed in the combustion chamber, and the combustion air in the combustion chamber Increases density. As a result, a stable combustion state of the water-oil mixed fuel can be obtained in the combustion chamber. As a result, the water-oil mixed fuel can be stably heated by the fuel heating unit, and the combustion state of the water-oil mixed fuel in the combustion chamber can be further stabilized. Further, the water-oil mixed fuel can be completely burned in the combustion chamber, and the inconvenience that carbon monoxide, soot and the like remain in the combustion gas can be prevented.

  Further, in the above combustion air supply section, the combustion air is supplied to one end of the air passage tube, and therefore, when the combustion air is supplied by a branching air supply tube in the vicinity of one end of the air passage tube as in the prior art As a result, the disturbance of the flow of combustion air in the air passage pipe can be suppressed. As a result, the swirling flow of the combustion air can be stably formed in the air passage pipe, and consequently the combustion state of the water-oil mixed fuel in the combustion chamber can be stabilized.

  Further, in the combustion air supply section, since the rectifying blade and the swirling blade on the other end side of the rectifying blade are arranged in the air passage pipe, the combustion air flowing into the air passage pipe from one end is rectified by the rectifying blade. In addition, a stable swirl flow can be generated by changing the flow to swirl. As a result, a swirl flow of combustion air can be stably formed in the combustion chamber, and the combustion state of the water-oil mixed fuel in the combustion chamber can be stabilized.

  In the combustion burner of one embodiment, the air passage pipe is formed so that combustion air is supplied to one end of the air passage pipe substantially in parallel with the central axis.

  According to the above embodiment, by appropriately supplying combustion air to the air passage pipe, a swirl flow with less turbulence can be stably formed in the air passage pipe. As a result, a swirl flow of combustion air can be stably formed in the combustion chamber, and the combustion state of the water-oil mixed fuel in the combustion chamber can be stabilized.

  In the combustion burner of one embodiment, the rectifying blade has a plurality of blades extending in parallel with the central axis of the air passage tube.

  According to the embodiment, in the air passage pipe, the combustion air supplied to one end can be appropriately rectified by the rectifying blade and sent to the swirl blade.

  In the combustion burner of one embodiment, the swirl vane has a plurality of blades that are at least partially curved or inclined with respect to the central axis of the air passage tube.

  According to the embodiment, in the air passage pipe, the flow of combustion air rectified by the rectifying blades can be appropriately changed by the swirling blades to form a swirling flow.

  In the combustion burner of one embodiment, the fuel heating part is a spiral heat exchange pipe wound around the outer peripheral side of the combustion chamber.

  According to the above embodiment, since the water / oil mixed fuel guided to the spiral heat exchange pipe can be effectively heated by the heat of the combustion chamber, the water / oil mixed fuel can be reliably injected as it is injected from the fuel injection nozzle. Combustion can further stabilize the combustion state of the water-oil mixed fuel in the combustion chamber.

  The combustion burner according to an embodiment bypasses the downstream side and the upstream side of the fuel heating unit so that the fuel oil mixed fuel is supplied to the fuel heating unit as injection of the water / oil mixed fuel from the fuel injection nozzle stops. It is formed to circulate.

  According to the above-described embodiment, as the injection of the water / oil mixed fuel from the fuel injection nozzle stops and the combustion operation of the combustion burner stops, the water / oil mixed fuel is circulated in the fuel heating unit, thereby Can hold the water-oil mixed fuel without separation. Therefore, when resuming the combustion operation of the combustion burner, it is possible to quickly start the combustion of the water-oil mixed fuel without causing ignition failure due to separation of water and oil.

  In the combustion burner of one embodiment, the water / oil mixed fuel supplied to the fuel heating unit has an oil mixing ratio of 50% or less.

  According to the above embodiment, the amount of nitrogen oxides and sulfur oxides and the amount of soot emissions are reduced by burning a water-oil mixed fuel with an oil mixing ratio of 50% or less and a high water content. It is possible to improve the combustion efficiency of the oil component. By improving the combustion efficiency of oil components, it is possible to obtain the same combustion energy with less oil consumption than when only oil components are used as fuel, reducing fuel costs and reducing carbon dioxide emissions. Can be achieved. Here, the oil mixing ratio refers to the ratio of the mass of the oil forming the water / oil mixed fuel to the whole oil, and is a value obtained by (mass of oil) / (mass of the water / oil mixed fuel).

  A water / oil mixed fuel having an oil mixing ratio value of 50% or less is one that can be stably burned by the combustion burner of the present invention, rather than combusting an emulsion fuel to which an emulsifier is added as in the prior art. It is possible to reduce emission of harmful substances, improve combustion efficiency, and stabilize the combustion state. Here, as the oil forming the water-oil mixed fuel, fossil fuels such as heavy oil, kerosene, and light oil can be used as well as waste oil. Waste oil includes waste edible oil, lubricating oil, insulating oil, washing Various things such as oil and cutting oil can be used.

  In the combustion burner of one embodiment, the water / oil mixed fuel supplied to the fuel heating unit is pressurized to a pressure of 0.5 to 30 MPa.

  According to the embodiment, the water-oil mixed fuel pressurized to the pressure is heated by the fuel heating unit and injected from the fuel injection nozzle, so that it is appropriately vaporized and combusted with high efficiency. Can do.

A burner unit according to another aspect of the present invention comprises a plurality of the combustion burners,
The plurality of combustion burners includes a main burner and a plurality of sub-burners arranged at substantially equal angular intervals around the central axis of the main burner,
The oil mixing ratio of the water / oil mixed fuel supplied to the main burner is larger than the oil mixing ratio of the water / oil mixed fuel supplied to the sub-burner.

  According to the above configuration, since a plurality of combustion burners are provided, the thermal power is large, and the combustion state is stabilized by burning the water-oil mixed fuel with a large oil mixing ratio in the main burner, so that the combustion state is stable as a whole. Burner unit can be obtained.

  Here, the oil mixing ratio refers to the ratio of the mass of the oil forming the water / oil mixed fuel to the whole oil, and is a value obtained by (mass of oil) / (mass of the water / oil mixed fuel).

  In the burner unit of one embodiment, the fuel heating section of the sub-burner is disposed on the outer peripheral side of the combustion chamber of the main burner, and heats the water / oil mixed fuel burned in the sub-burner with the heat of the combustion chamber of the main burner. It is formed as follows.

  According to the above embodiment, after the combustion of the main burner is started, the fuel oil mixed fuel is heated by the fuel heating unit of the sub burner using the heat of the combustion chamber of the main burner, thereby reliably burning the sub burner. Can start. Further, by arranging the fuel heating section of the sub-burner at a position on the outer peripheral side of the combustion chamber of the main burner and surrounded by the combustion chambers of the plurality of sub-burners, a water-oil mixed fuel with a relatively small oil mixing ratio Can be sufficiently heated and sent to the combustion chamber of the auxiliary burner, so that the combustion state in the combustion chamber of the auxiliary burner can be stabilized.

  According to the present invention, a swirl flow is formed by the action of the rectifying blades and swirl vanes in the air passage pipe of the combustion air supply unit, thereby forming a swirl flow of the combustion air in the combustion chamber, thereby injecting from the fuel injection nozzle. The water-oil mixed fuel and the combustion air thus mixed can be sufficiently mixed and the density of the combustion air in the combustion chamber can be increased to stably burn the water-oil mixed fuel. As a result, the combustion state of the water-oil mixed fuel can be stabilized and completely burned, and inconveniences such as carbon monoxide and dust remaining in the combustion gas can be prevented.

  FIG. 1 is a schematic cross-sectional view showing a combustion burner according to an embodiment of the present invention. This combustion burner 1 burns water-oil mixed fuel obtained by mixing water and oil, and has a cylindrical burner casing 21 and a generally cylindrical combustion chamber 22 formed inside the burner casing 21. , A heating coil 23 as a fuel heating unit surrounding the outer peripheral side of the combustion chamber 22, and a combustion air supply unit 5 connected to one end side of the combustion chamber 22.

  An opening 21a is formed in the other end surface of the burner casing 21, and the opening 21a is formed through the opening 21a so as to release flame and combustion gas to a combustion furnace, for example.

  The combustion chamber 22 is formed on the inner peripheral side of a cylindrical wall 25 that is continuous with the opening 21 a of the burner casing and a mortar-shaped wall 26 that is continuous with the other end of the cylindrical wall 25. A heating coil 23 is arranged so as to surround the outer peripheral surface of the other end portion of the cylindrical wall 25.

  The heating coil 23 is formed of a heat exchange pipe wound in a double spiral shape in the radial direction, and a pressurized fuel connected to a plunger pump 34 described later at one end of the inner coil 23a on the inner diameter side. A supply pipe 35 is connected. Further, a fuel supply pipe 56 described later is connected to one end of the outer coil 23b on the outer diameter side. The water / oil mixed fuel pressurized to a predetermined pressure by the plunger pump 34 is guided to one end of the inner coil 23a through the heated fuel supply pipe 35 as indicated by an arrow Fi, and the inner coil 23a is directed from one end to the other end. Flowing. Thereafter, the other end moves to the outer coil 23b, and then the outer coil 23b flows from the other end toward the one end, and then flows into the fuel supply pipe 56 and is sent to the combustion air supply unit 5 as indicated by an arrow Fr. It is done. The heating coil 23 has an inner coil 23a having a diameter of about 300 mm, an outer coil 23b having a diameter of about 340, an axial dimension of 180 mm, and an extension set to a helical pitch of 20 m or more. Yes. The water-oil mixed fuel is sufficiently heated by the heat of the combustion chamber 22 in the process of flowing through a heating path of 20 m or more of the heating coil 23.

  At one end of the mortar-like wall 26 that defines the combustion chamber 22, a combustion air outlet 52 a is opened. An ignition port 28 is provided in the vicinity of the air outlet 52 a of the mortar-shaped wall 26, and a pilot burner 29 is connected to the ignition port 28. When the burner 1 is started, a flame is emitted from the pilot burner 29 to ignite the water / oil mixed fuel. A region surrounded by the burner casing 21, the cylindrical wall 25, and the mortar-shaped wall 26 is filled with a heat insulating material 11, and heat insulation in the combustion chamber 22 and overheating prevention of the burner casing 21 are performed.

  The combustion air supply unit 5 is supplied with combustion air at one end to form an air passage 51 inside, an air passage pipe 52, a rectifying blade 54 disposed in the air passage pipe 52, and an air passage pipe 52. Two swirl vanes 53 and 53 are arranged on the air outlet 52a side of the rectifying vane 54.

  The other end of the air passage pipe 52 is connected to one end of the mortar-shaped wall 26, and a combustion air blow-out port 52 a is formed at a communication portion between the air passage pipe 52 and the mortar-shaped wall 26. An air supply pipe 71 is connected to one end of the air passage pipe 52, and combustion air of a predetermined flow rate is supplied from the sirocco type blower 7 through the air supply pipe 71. One end side portion of the air passage pipe 52 protrudes from one end surface of the burner casing 21. A fuel supply pipe 56 is coaxially disposed in the air passage pipe 52, and a fuel injection nozzle 57 is attached to the tip of the fuel supply pipe 56. The fuel supply pipe 56 is connected to the downstream end of the heating coil 23, that is, one end of the outer coil 23 b of the heating coil 23. Two swirl vanes 53 and 53 are externally fitted and fixed to the outer peripheral surface near the tip of the fuel supply pipe 56 and the outer peripheral surface near the center of the fuel supply pipe 56. Further, one rectifying blade 54 is fitted and fixed to the outer peripheral surface near one end of the fuel supply pipe 56. The fuel injection nozzle 57 is disposed at the center in the axial view of the air outlet 52a.

  FIG. 2 is a view showing a state in which the combustion burner 1 is viewed in the axial direction from the opening side 21a of the burner casing. As shown in FIG. 2, the combustion chamber 22 is formed inside the opening 21 a of the burner casing 21, and the fuel injection nozzle 57 is disposed at the center of the blowout port 52 a that opens at one end surface of the combustion chamber 22. . The blades 532, 532,... Of the swirl blade 53 extend radially around and behind the fuel injection nozzle 57.

  FIG. 3 is a perspective view showing the swirl vane 53, the rectifying vane 54, the fuel supply pipe 56 and the fuel injection nozzle 57 arranged in the combustion air supply unit 5. These two swirling blades 53, 53, the rectifying blade 54 and the fuel injection nozzle 57 are integrated with a fuel supply pipe 56, and the integrated assembly is inserted into the air passage pipe 52 from one end. It is configured to be worn.

  The swirl vane 53 includes a tubular fixing portion 531 that is fitted around the fuel supply pipe 56 and twelve blades 532, 532,... Radially fixed to the outer peripheral surface of the fixing portion 531. The blade 532 has an elongated trapezoidal shape in which an axial dimension is larger than a radial dimension, and an edge of one end is inclined toward the other end side toward the outer side in the radial direction. The blade 532 is fixed to the fixing portion 531 so as to be inclined with respect to the central axis of the fuel supply pipe 56, that is, the central axis of the air passage pipe 52. The swirl vane 53 on the front end side of the fuel supply pipe 56 is arranged so that the front end edge of the blade 532 is at substantially the same axial position as the fuel injection port of the fuel injection nozzle 57. The blade 532 of the swirl vane 53 may be formed such that the axial edge on the inner diameter side is formed parallel to the central axis, and the outer diameter side portion is curved in the circumferential direction toward the distal end side. Alternatively, the entire blade 532 may be formed to be inclined with respect to the central axis.

  The rectifying blade 54 includes a tubular fixed portion 541 that is fitted on the fuel supply pipe 56, and eight blades 542, 542,... That are radially fixed to the outer peripheral surface of the fixed portion 541. The blade 542 has a rectangular shape whose axial dimension is larger than the radial dimension, and extends parallel to the central axis of the fuel supply pipe 56, that is, the central axis of the air passage pipe 52.

  As described above, the rectifying blade 54 is disposed in the air passage pipe 52 in the vicinity of one end to which the combustion air is supplied, and the two swirl blades 53 are disposed at a predetermined distance on the downstream side of the rectifying blade 54. is doing. Thereby, the combustion air supplied from one end of the air passage 51 can be rectified by the rectifying blades 54, and the swirl flow can be stably formed by the two swirl blades 53. Combustion air is supplied to the air passage pipe 52 through an air supply pipe 71 connected to one end at one end of the air passage pipe 52 substantially parallel to the central axis. This reduces the turbulence of the flow of combustion air in the air passage pipe 52, compared to the case where the combustion air is supplied to the air passage pipe in a direction inclined with respect to the central axis through the air supply pipe connected in a branch shape as in the prior art. In addition, a stable swirl flow can be formed. The shape, size, and number of blades 532 of the swirl blade 53 and the shape, size, and number of blades 542 of the rectifying blade 54 can be changed as appropriate according to the flow rate of combustion air to be supplied and the size of the air passage 51. . In addition, the number of swirling blades 53 and rectifying blades 54 arranged in the air passage 51 can be changed as appropriate. For example, three or more swirl vanes 53 having blades 532 whose axial dimension is smaller than the radial dimension may be arranged in the air passage 51. Further, two or more rectifying blades 54 having blades 542 having a smaller axial dimension than the radial dimension may be arranged in the air passage 51.

  FIG. 4 is a schematic diagram showing the combustion burner 1 and the fuel supply device 3 that generates and supplies water / oil mixed fuel to the combustion burner 1. As shown in FIG. 4, the fuel supply device 3 mixes a water tank 31 for storing water, an oil tank 32 for storing oil, water supplied from the water tank 31 and oil supplied from the oil tank 32. And a plunger pump 34 that pressurizes the water-oil mixed fuel supplied from the mixing device 33.

  A water supply pipe 310 is connected to the water tank 31, and water is supplied to the mixing device 33 by a pump 311 provided in the water supply pipe 310. The water supply pipe 310 is provided with a flow meter 312 and a control valve 313. An oil supply pipe 320 is connected to the oil tank 32, and oil is supplied to the mixing device 33 by a pump 321 provided in the oil supply pipe 320. A flow meter 322 and a control valve 323 are interposed in the oil supply pipe 320. The mixing device 33 includes a stirring blade 331 that stirs the water supplied from the water supply pipe 310 and the oil supplied from the oil supply pipe 320, and a motor 332 that drives the stirring blade 331. A plunger pump 34 is connected to the downstream side of the mixing device 33. This plunger pump 34 pressurizes the water / oil mixed fuel to 0.5 to 30 MPa and supplies it to the heating coil 23 of the combustion burner 1 through the pressurized fuel supply pipe 35. A fuel supply pipe 56 is connected to the downstream side of the heating coil 23, and a fuel injection nozzle 57 is provided at the tip of the fuel supply pipe 56.

  A three-way valve 361 is interposed in the middle of the fuel supply pipe 56, and the bypass pipe 36 branched from the three-way valve 361 is connected to the plunger pump 34 on the upstream side of the heating coil 23 and the pressurized fuel supply pipe 35. ing. A pressure gauge 351 is connected to the pressurized fuel supply pipe 35. The combustion burner 1 is provided with a temperature sensor 201 for detecting the temperature in the combustion chamber 22 and a temperature sensor 202 for detecting the fuel temperature in the fuel supply pipe 56. Detection values of the flow meters 312, 322, pressure gauge 351, and temperature sensors 201, 202 are input to a control device (not shown), and the pumps 311, 321, control valves 313, 323, motor 332 are based on these input values. The operation of the plunger pump 34 is controlled by a control device.

  The combustion burner 1 configured as described above operates as follows. First, under the control of the control device, the control valves 313 and 323 of the fuel supply device 3 are opened and the pumps 311 and 321 are activated, so that the oil from the oil tank 32 and the water from the water tank 31 enter the mixing device 33. Supplied. In addition, the motor 332 of the mixing device 33 is started, and the operation of the stirring blade 331 is started, so that water / oil mixed fuel having a predetermined oil mixing ratio is generated in the mixing device 33. When a predetermined amount of the water-oil mixed fuel is generated in the mixing device 33, the plunger pump 34 is activated, and the water-oil mixed fuel pressurized to a predetermined pressure is supplied to the pressurized fuel supply pipe 35, the heating coil 23, and the fuel supply pipe. 56 is injected from the fuel injection nozzle 57 into the combustion chamber 22. At the same time, the blower 7 is started, and the combustion air supplied to the air passage pipe 52 through the air supply pipe 71 is rectified by the rectifying blades 54 and then changed into a swirling flow by the two swirling blades 53, 53. It blows out into the combustion chamber 22 from the blower outlet 52a. Subsequently, the flame of the pilot burner 29 is released from the ignition port 28, igniting the water / oil mixed fuel injected from the fuel injection nozzle 57, and generation of flame and combustion gas is started in the combustion chamber 22.

  As the temperature of the combustion chamber 22 rises, the heating effect of the water / oil mixed fuel by the heating coil 23 increases, and the water / oil mixed fuel is sufficiently heated by the heating coil 23 to become high temperature and pressure. When the temperature sensor 202 detects that the fuel temperature in the fuel supply pipe 56 has reached a predetermined reference temperature, the operation of the plunger pump 34 is controlled and adjusted to the discharge flow rate of the water / oil mixed fuel corresponding to the steady operation. Is done.

  In a steady operation of the combustion burner 1, the water-oil mixed fuel having a predetermined pressure discharged from the plunger pump 34 to the pressurized fuel supply pipe 35 is heated by the heating coil 23 to become a high temperature and a high pressure, and passes through the fuel supply pipe 56. The fuel is injected from the injection nozzle 57 into the combustion chamber 22. As the water-oil mixed fuel is injected into the combustion chamber 22 from the fuel injection nozzle 57, almost all is vaporized and combusted. Here, a swirling flow of combustion air around the central axis substantially the same as the central axis of the fuel injection nozzle 57 in the injection direction of the water / oil mixed fuel is blown out from the outlet 52a in which the fuel injection nozzle 57 is disposed in the center. The combustion air ejected from the air outlet 52a is in a stable swirl flow by the rectifying blades 54 and swirl blades 53 in the air passage tube 52, and the swirl flow of the combustion air is stably formed in the combustion chamber 22. . The water / oil mixed fuel injected from the fuel injection nozzle 57 is sufficiently mixed with the combustion air by the swirling flow. In addition, the combustion air is supplied to the combustion chamber 22 in a swirling manner, so that the residence time of the combustion air in the combustion chamber 22 is increased and the density of the combustion air is increased. As a result, substantially all combustion components of the water-oil mixed fuel are burned and burnt completely. In addition, since a stable swirl flow can be supplied to the combustion chamber 22 by the combustion air supply unit 5, the flow and supply amount of the combustion air are stabilized, and the combustion state of the water-oil mixed fuel in the combustion chamber 22 is effectively achieved. Stabilize. As a result, the disadvantage that carbon monoxide, soot, etc. remain in the combustion gas is effectively prevented.

  In the combustion burner 1 of the present embodiment, the supply operation of the water-oil mixed fuel by the fuel supply device 3 is controlled based on, for example, the combustion state of the combustion furnace that supplies the flame and the combustion gas. For example, when the combustion load of the combustion furnace increases and the temperature of the combustion chamber 22 decreases, the operation of the plunger pump 34 is controlled based on the detection value of the temperature sensor 201 and the discharge flow rate of the water-oil mixed fuel increases. The amount of water-oil mixed fuel injection from the fuel injection nozzle 57 increases. At the same time, the operation of the blower 7 is controlled so that the air volume according to the discharge flow rate of the plunger pump 34 is obtained, the flow rate of the combustion air blown out from the outlet 52a is controlled, and the air-fuel ratio in the combustion chamber 22 becomes a predetermined value. Maintained at the value. In addition, you may control the plunger pump 34 and the air blower 7 so that it may become an air fuel ratio according to temperature. By controlling the injection amount of the water / oil mixed fuel from the fuel injection nozzle 57 and the flow rate of the combustion air from the outlet 52a, the amount of heat accompanying combustion in the combustion chamber 22 increases, and the combustion chamber 22 Becomes the predetermined target temperature.

  By the way, this combustion burner 1 circulates the water-oil mixed fuel to the heating coil 23 when stopping the combustion operation. That is, when stopping the injection of the water / oil mixed fuel from the fuel injection nozzle 57, the valve position of the three-way valve 361 is switched and the downstream side of the heating coil 23 is connected to the bypass pipe 36. Further, the operation of the plunger pump 34 is controlled to set the discharge flow rate to a predetermined circulation flow rate. Thus, a circulation path is formed from the plunger pump 34 via the pressurized fuel supply pipe 35, the heating coil 23, the fuel supply pipe 56, the three-way valve 361, and the bypass pipe 36. To form a circulating flow. Thus, even when the injection of the water / oil mixed fuel from the fuel injection nozzle 57 is stopped, the water / oil mixed fuel is held immediately upstream of the fuel injection nozzle 57 without being separated into water and oil. When the combustion operation is resumed, the three-way valve 361 is switched to connect the upstream side of the fuel supply pipe 56 to the downstream side, and the plunger pump 34 is returned to the normal discharge flow rate. Accordingly, the water / oil mixed fuel held in the circulation path can be sent to the downstream side of the fuel supply pipe 56, and the appropriately mixed water / oil mixed fuel can be quickly injected from the fuel injection nozzle 57. As a result, a combustion state close to a steady state can be quickly generated in the combustion chamber 22 without causing an ignition failure due to separation of water and oil.

  When a combustion experiment was performed using a water-oil mixed fuel obtained by mixing A heavy oil and water with the combustion burner 1 of the present embodiment, when the water-oil mixed fuel was burned, A contained in the water-oil mixed fuel It became clear that a larger amount of heat was obtained than when only heavy oil was burned. That is, in the water-oil mixed fuel obtained by mixing A heavy oil and water, the amount of A heavy oil mixed when forming the water-oil mixed fuel is more than the amount necessary to obtain the same amount of heat with only the A heavy oil. Less. Therefore, the combustion efficiency of heavy fuel oil A can be improved, the amount of heavy fuel oil A used can be effectively reduced, fuel costs can be reduced, and carbon dioxide emissions can be reduced. Further, since the combustion gas of the combustion burner 1 has a significantly smaller amount of unburned components and soot as compared with the case where only A heavy oil is burned, air pollution can be effectively prevented.

  Moreover, according to the combustion burner 1 of this embodiment, the water-oil mixed fuel whose oil mixing ratio is 20% or more and 50% or less can be burned stably. Here, the oil mixing ratio refers to the ratio of the mass of the oil forming the water / oil mixed fuel to the whole oil, and is a value obtained by (mass of oil) / (mass of the water / oil mixed fuel). The water / oil mixed fuel is preferably not a emulsion fuel to which an emulsifier is added, but simply a mixed fuel in which water and oil are mixed with stirring. The combustion burner 1 of the present embodiment is a water-oil mixed fuel in which water and oil are mixed by the action of the heating coil 23 as a fuel heating unit and the combustion air supply unit 5, and the oil mixing ratio is 50% or less. However, it can be burned stably. As a result, emissions of nitrogen oxides and sulfur oxides and emissions of dust can be effectively reduced, and the combustion efficiency of oil components is improved to reduce fuel costs and carbon dioxide emissions. it can.

  FIG. 5 is a front view showing the burner unit according to the embodiment of the present invention. FIG. 5 shows a state in which the burner unit is viewed from the opening side from which flame and combustion gas are released, as in FIG.

  This burner unit 601 is configured by combining a plurality of combustion burners having substantially the same structure as the combustion burner 1 of FIG. In the present embodiment, the same reference numerals are given to substantially the same components as those in the embodiment of the combustion burner 1, and detailed description thereof will be omitted.

  The burner unit 601 includes a main burner 611 disposed in the center in a front view, and four sub-burners 621, 622, 623, and 624 disposed at equiangular intervals around the central axis of the main burner 611. Prepare. The main burner 611 and the auxiliary burners 621 to 624 share one burner casing 620, and each burner is burned in a plurality of openings 611a, 621a, 622a, 623a, 624a formed on the end face of the burner casing 620. The chambers 22 are connected to each other.

  A heating coil 615 as a fuel heating portion of the main burner 611 is disposed on the outer peripheral side of the combustion chamber 22 of the main burner 611 in the burner casing 620, and the auxiliary burners 621 to 621 are disposed on the outer peripheral side of the heating coil 615. A heating coil 625 as a fuel heating unit 624 is arranged. Both of the heating coil 615 of the main burner and the heating coil 625 of the sub burner are formed of a spiral heat exchange pipe. The main burner 611 is supplied with a water / oil mixed fuel having an oil: water mixing ratio of 1: 1, that is, an oil mixing ratio of 50%, from a fuel supply device (not shown). The water / oil mixed fuel with the oil / water mixing ratio of 50% is heated by the heating coil 615 and injected from the fuel injection nozzle 57 to burn. On the other hand, the sub-burners 621 to 624 are from the fuel supply device provided separately from the fuel supply device of the main burner 611, and the oil / water mixture ratio is 1: 4, that is, the oil mixing ratio is 20%. Mixed fuel is supplied. The water / oil mixed fuel having an oil mixing ratio of 20% is heated by the heating coil 625 and injected from the fuel injection nozzle 57 to burn.

  According to this burner unit 601, since it has a plurality of combustion burners 611, 621 to 624, it can be used as a heat source of a large-sized thermal apparatus such as a boiler of a power generation facility. In addition, by setting the oil mixing ratio of the water / oil mixed fuel combusted in the main burner 611 to be larger than the oil mixing ratio of the water / oil mixed fuel combusted in the auxiliary burners 621 to 624, the combustion state of the entire burner unit is stabilized. Can be made.

  When the burner unit 601 is started, first, the main burner 611 is started to start combustion, and then the auxiliary burners 621 to 624 are started. As a result, by using the heat of the combustion chamber 22 of the main burner and heating the water / oil mixed fuel with the heating coil 625 of the sub burner, a sufficiently high temperature and high pressure can be obtained. Can start. Further, since the heating coil 625 of the sub-burner is disposed on the outer peripheral side of the combustion chamber 22 of the main burner and surrounded by the combustion chambers 22 of the four sub-burners, the water / oil mixing in the heating coil 625 is performed. The fuel can be heated sufficiently. Therefore, even though the sub-burners 621 to 624 use the water-oil mixed fuel with a relatively small oil mixing ratio, the water-oil mixed fuel is sufficiently heated and effectively vaporized in the combustion chamber 22 of the sub-burner for combustion. Can be made. As a result, the combustion state of the auxiliary burners 621 to 624 can be stabilized, and as a result, the combustion state of the entire burner unit 601 can be stabilized.

  In the above embodiment, the number of sub-burners included in the burner unit 601 is not limited to four. Further, the oil mixing ratio of the water / oil mixed fuel burned by the main burner 611 and the oil mixing ratio of the water / oil mixed fuel burned by the sub-burners 621 to 624 vary depending on the ability to be imparted to the burner unit 601. The value can be set. In short, the oil mixing ratio of the main burner 611 may be set larger than the oil mixing ratio of the auxiliary burners 621 to 624.

It is sectional drawing which shows the combustion burner of embodiment of this invention. It is a front view which shows a mode that the combustion burner was seen from the opening side of the burner casing. It is a perspective view which shows a turning blade | wing, a baffle blade, a fuel supply pipe, and a fuel injection nozzle. It is a figure which shows a combustion burner and a fuel supply apparatus typically. It is a front view which shows the burner unit of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Combustion burner 5 Combustion air supply part 22 Combustion chamber 23 Heating coil 51 Air passage 52 Air passage pipe 52a Outlet 53 Swirling blade 54 Rectification blade 57 Fuel injection nozzle

Claims (10)

A combustion burner for burning water-oil mixed fuel obtained by mixing water and oil,
A combustion chamber;
A fuel heating unit that is supplied with a water-oil mixed fuel pressurized to a predetermined pressure and heats the water-oil mixed fuel with the heat of the combustion chamber;
A combustion air outlet provided at one end of the combustion chamber;
A fuel injection nozzle disposed at the center of the combustion air outlet and injecting the water-oil mixed fuel heated by the fuel heating unit toward the other end of the combustion chamber;
An air passage pipe having the other end connected to the combustion air outlet and supplied with the combustion air at one end, a rectifying blade disposed in the air passage pipe to rectify the combustion air, and an air passage pipe in the air passage pipe A combustion burner comprising: a combustion air supply unit having a swirl vane disposed on the other end side of the rectifying vane to form a swirl flow of the combustion air. The combustion burner according to claim 1,
The combustion burner according to claim 1, wherein the air passage pipe is formed at one end of the air passage pipe so that combustion air is supplied substantially parallel to the central axis. The combustion burner according to claim 1,
A combustion burner, wherein the rectifying blade has a plurality of blades extending in parallel with a central axis of the air passage tube. The combustion burner according to claim 1,
The combustion burner, wherein the swirl vane has a plurality of blades that are at least partially curved or inclined with respect to a central axis of the air passage tube. The combustion burner according to claim 1,
The combustion burner according to claim 1, wherein the fuel heating unit is a spiral heat exchange pipe wound around an outer peripheral side of the combustion chamber. The combustion burner according to claim 1,
As the injection of the water-oil mixed fuel from the fuel injection nozzle stops, the downstream side and the upstream side of the fuel heating unit are bypassed, and the water-oil mixed fuel is circulated in the fuel heating unit. Combustion burner characterized by that. The combustion burner according to claim 1,
A combustion burner characterized in that the water-oil mixed fuel supplied to the fuel heating section has an oil mixing ratio of 50% or less. The combustion burner according to claim 1,
The combustion burner characterized in that the water / oil mixed fuel supplied to the fuel heating section is pressurized to a pressure of 0.5 to 30 MPa. A plurality of combustion burners according to claim 1;
The plurality of combustion burners includes a main burner and a plurality of sub-burners arranged at substantially equal angular intervals around the central axis of the main burner,
The burner unit, wherein an oil mixing ratio of the water-oil mixed fuel supplied to the main burner is larger than an oil mixing ratio of the water-oil mixed fuel supplied to the sub-burner. In the burner unit according to claim 9,
The fuel heating section of the sub-burner is disposed on the outer peripheral side of the combustion chamber of the main burner, and is configured to heat the water / oil mixed fuel burned in the sub-burner with the heat of the combustion chamber of the main burner. Characteristic burner unit.

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