JP4859798B2 - Boiler device and method for remodeling boiler device - Google Patents

Description

  The present invention relates to a boiler device that reduces NOx concentration and unburned content in combustion gas, and a method for remodeling the boiler device.

  In a boiler apparatus that burns fuel coal, oil, or gas to generate combustion gas, and uses this combustion gas to obtain high-temperature steam, nitrogen oxides contained in the combustion gas generated when the fuel is burned ( Reduction of NOx) concentration and reduction of unburned content are demanded.

  In order to meet the demands for reducing NOx concentration and reducing unburned fuel, boiler equipment uses the burner installed in the furnace to introduce fuel and air into the furnace and burn it to produce reducing combustion gas. Thereafter, a two-stage combustion method is applied in which combustion air is introduced from an after air port installed in a furnace located above the burner to completely burn the reducing combustion gas.

  In the above-described two-stage combustion method, the NOx concentration in the combustion gas can be reduced if the furnace height is increased so that the first stage combustion time becomes longer, but this increases the size of the boiler device. The construction cost of boiler equipment was increased.

  Therefore, as an improvement measure, a method of devising the configuration of the air port for two-stage combustion has been proposed.

  Japanese Patent Application Laid-Open No. 2006-132911 discloses that in order to reduce the unburned portion generated in the boiler, the directionality and mode of the air ejected from the after air port is changed according to the incomplete combustion region of the two-stage combustion method. A technology related to a boiler having a structure in which a nozzle mechanism for increasing the efficiency of mixing a complete combustion region and air is installed in an after air port is disclosed.

  Japanese Patent Laid-Open No. 9-126416 discloses a two-stage combustion boiler that reduces NOx in order to suppress the generation of unburned components contained in the ash falling on the bottom of the furnace, rather than the lowermost burner. A technology related to a boiler having a structure in which an auxiliary air outlet for introducing combustion air in a direction orthogonal to the jet flow from the burner is installed at a low position to reduce the unburned portion of the air-deficient furnace bottom.

  Japanese Patent Laid-Open No. 10-213309 discloses a pulverized coal mixture nozzle in a pulverized coal burner in order to ensure the ignition stability of the pulverized coal flame when the burner capacity is increased in response to an increase in the capacity of the boiler. The technology regarding the boiler of the structure which arrange | positioned the density | concentration separation body in this, or returned and arrange | positioned the pulverized coal mixture nozzle to the air nozzle is disclosed.

Japanese Patent Laid-Open No. 2006-132911 JP-A-9-126416 JP-A-10-213309

  However, in the respective technologies relating to the boilers described in JP-A-2006-132911, JP-A-9-126416, and JP-A-10-213309, they are generated when fuel is burned in the furnace of the boiler. To reduce the concentration of nitrogen oxides (NOx) contained in the combustion gas and to reduce the unburned content contained in the combustion gas, the height of the furnace must be increased. There was a problem that the construction cost increased.

  In addition, each of the technologies related to the boiler described above has a problem that there is no simple and effective device that removes ash adhering to the hopper portion of the furnace and suppresses ash adhesion.

  An object of the present invention is to provide a boiler device having a compact structure that reduces nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace, and It is in providing the remodeling method of a boiler apparatus.

  A boiler device according to the present invention includes a rectangular parallelepiped portion including a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper portion provided at a lower portion of the rectangular parallelepiped portion. And a plurality of burners installed on the front wall and the rear wall of the furnace for supplying fuel and combustion air into the furnace for combustion, and the front wall and the rear wall of the furnace as the upper part of the burner And a plurality of after air ports for supplying combustion air into the furnace, the burner disposed at the lowermost position among the burners installed on the front wall and the rear wall of the furnace. A side burner for injecting and burning fuel is installed on the side wall of the furnace of the rectangular parallelepiped part at the same height as or below the burner, or the side wall of the hopper part located below the burner. It is characterized by.

  Further, the boiler device of the present invention includes a rectangular parallelepiped portion including a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper portion provided at a lower portion of the rectangular parallelepiped portion. A boiler apparatus, and a plurality of burners installed on the front wall and the rear wall of the furnace, respectively, for supplying and burning fuel and combustion air into the furnace, the front wall of the furnace The side wall of the furnace at the lower part of the rectangular parallelepiped part which is the same height as the burner arranged at the lowest position among the burners installed on the rear wall or the position below the burner, or a position below the burner A side burner for injecting and burning fuel on the side wall of the hopper is formed.

  Further, the boiler device remodeling method of the present invention is provided in a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a lower portion of the rectangular parallelepiped portion. A furnace having a hopper, a plurality of burners installed at three or more stages on the front wall and the rear wall of the furnace, supplying fuel and combustion air into the furnace and burning, and the upper part of the burner In a method for remodeling a boiler apparatus having a plurality of after-air ports that are respectively installed on a front wall and a rear wall of a furnace and supply combustion air into the furnace, an existing installation installed on the front wall or the rear wall of the furnace The uppermost burner of the burners is removed, and the burner is disposed at the same height as the lowermost burner among the burners installed on the front wall and the rear wall of the furnace or at a position below the burner. Side wall of the rectangular parallelepiped furnace, or Characterized by modifying the side burner to burn by jetting fuel into the side wall of the hopper which is a position below the burner for installation.

  Further, the boiler device remodeling method of the present invention is provided in a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a lower portion of the rectangular parallelepiped portion. Of a boiler apparatus comprising a furnace equipped with a hopper and a plurality of burners installed on the front wall and the rear wall of the furnace in three or more stages to supply fuel and combustion air into the furnace for combustion In the method, the uppermost burner is removed from the existing burners installed on the front wall or the rear wall of the furnace, and is arranged at the lowest position among the burners installed on the front wall and the rear wall of the furnace. A side burner for injecting and burning fuel on the side wall of the furnace of the rectangular parallelepiped part which is the same height as the burner burned or below the burner, or on the side wall of the hopper part located below the burner Remodeling to install And butterflies.

  According to the present invention, a boiler device having a compact structure for reducing nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace, and A boiler device remodeling method can be realized.

  Next, a boiler device and a boiler device remodeling method according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows the overall configuration of a boiler apparatus according to a first embodiment which is an embodiment of the present invention.

  The boiler apparatus of FIG. 1 is a counter combustion type in which solid fuel such as pulverized coal obtained by pulverizing coal is supplied from a burner installed facing the front wall and the rear wall of the furnace 11 of the boiler 1 and floats in the furnace. It is a structural example of a boiler.

  In the boiler apparatus of the present embodiment, which is the first embodiment, coal, which is solid fuel, is used as fuel, but heavy oil, natural gas, or the like may be burned instead of solid fuel.

  In FIG. 1, a furnace 11 constituting a boiler 10 which is a boiler apparatus of the present embodiment is arranged between a front wall 12, a rear wall 13 facing the front wall, and the front wall 12 and the rear wall 13. It is comprised from the provided left and right side walls 14, and the horizontal cross section forms the upper part of the furnace 11 used as a rectangular parallelepiped part.

  Further, a hopper 15 for collecting ash generated in the furnace 11 is provided at a lower part of the rectangular parallelepiped part of the furnace 11 to form a lower part of the furnace.

  A plurality of burners 2 are disposed on the front wall 12 and the rear wall 13 of the furnace 11 so as to inject and burn coal and combustion air into the furnace 11, and these burners 2 are disposed on the front wall 12 and the rear wall 13. A plurality of stages are installed in the vertical direction of the wall 13.

  A plurality of after-air ports 3 are arranged opposite to the burner 2 on the front wall 12 and the rear wall 13 positioned above the installation location of the burner 2.

  The burner 2 injects and burns a mixture of coal and combustion air into the furnace 11 at a theoretical air ratio or less (for example, 0.8) to form an incomplete combustion region of combustion gas in the furnace 11.

  The after-air port 3 injects after-air 22 as combustion air into the combustion gas in the incomplete combustion region in the furnace 11 formed by the burner 2 to completely combust the combustion gas in the region, and substantially eliminates the unburned portion. Burn completely.

  By the way, in the two-stage combustion type boiler that performs the above-described combustion, in order to reduce NOx, the first stage in which coal and combustion air are supplied from the burner 2 into the furnace 11 to form an incomplete combustion region. It is designed to increase the interval between the installation positions of the burner 2 and the after-air port 3 so as to increase the combustion time.

  In order to increase the distance between the installation positions of the burner 2 and the after-air port 3, a method of raising the installation position of the after-air port 3 to a position higher than the installation position of the burner 2, and the installation position of the burner 2 of the after-air port 3 There is a method of lowering to a position below the installation position.

  However, the former method increases the size of the boiler 10 in the height direction.

  In the latter method, since the distance from the bent portion between the hopper 15 and the front wall 12 or the rear wall 13 of the furnace 11 cannot be less than a certain size, the installation position of the lowermost stage of the burner 2 is lowered too much. I can't.

  The installation position of the lowermost stage of the burner 2 is designed in consideration of insufficient boiler strength and slagging (ash adhesion) of the hopper 15 according to the size of the boiler and the fuel to be burned.

  On the other hand, the internal space of the hopper 15 does not contribute much to increase the combustion time.

  This is because the high-temperature combustion gas generated by the combustion flows in the furnace 11 from the bottom to the top, so that the hopper portion 15 tends to be a water stop area.

  Further, the internal temperature of the hopper 15 is low, and heat absorption at the furnace wall of the hopper 15 is small.

  Therefore, it is advantageous that the size of the hopper 15 is smaller in terms of combustion and heat absorption of the boiler.

  The inclination angle of the front wall or the rear wall surface of the hopper part constituting the hopper part 15 is such that the ash falling from the vicinity of the ceiling wall 17 of the furnace 11 can be efficiently collected and collected on the furnace bottom 16. The inclination angle of 15 wall surfaces is set to a desired angle range.

  In a boiler in which the distance between the front wall 12 and the rear wall 13 of the furnace 11 is greatly separated, the size of the hopper 15 is inevitably large.

  Therefore, the hopper portion 15 provided at the lower part of the furnace 11 which is located below the burner 2 installed at the lowermost stage among the plural stages of burners 2 installed on the front wall 12 and the rear wall 13 of the furnace 11. A side burner 1 is disposed on the side wall 14 so that coal and combustion air are jetted into the furnace 11 and burned.

  The side burner 1 injects and burns a mixture of coal and combustion air having a theoretical air ratio or less (for example, 0.8) into the furnace 11 to form an incomplete combustion region in the furnace 11.

  By installing the side burner 1 on the side wall 14 of the hopper part 15, the side wall 14 of the hopper part 15 that is lower than the position of the lowermost burner 2 provided on the front wall 12 and the rear wall 13 of the furnace 11 is provided. Since the side burner 1 for injecting and burning coal and combustion air into the furnace 11 can be installed, the distance between the side burner 1 and the after-air port 3 is larger than the distance between the bottom burner 2 and the after-air port 3. Can be set larger.

  As a result, the combustion time during which the combustion gas burns in the incomplete combustion region in the furnace 11 becomes longer, and the generation of NOx in the combustion gas can be suppressed.

  Further, since the combustion time for burning the combustion gas becomes longer, combustion of the combustion gas in the incomplete combustion region sufficiently proceeds until reaching the after-air port 3, and in the complete combustion region on the downstream side of the after-air port 3 Since the unburned portion of the ash can be burned sufficiently, the unburned portion in the ash is greatly reduced.

  Further, even in the vicinity of the hopper 15, the temperature in the furnace rises due to the combustion of the fuel supplied from the side burner 1, and the heat absorption of the furnace wall of the hopper 15 is improved.

  Thus, the heat absorption amount increases in the incomplete combustion region in the furnace 11 below the after air port 3, so that the temperature in the furnace near the after air port 3 decreases.

  Therefore, the temperature of the complete combustion region in the furnace 11 also decreases, the generation of NOx in the high temperature oxidation region decreases, and the concentration of NOx in the combustion gas can be further suppressed.

  The coal 27 supplied to the burner 2 provided on the front wall 12 and the rear wall 13 of the furnace 11 is temporarily stored in the coal bunker 28, and the coal 27 stored in the coal bunker 28 is supplied to the coal pulverizer 30 by the coal feeder 29. And pulverized to produce pulverized coal.

  The coal 27 crushed by the coal pulverizer 30 is conveyed to the burner 2 by the burner coal conveying air 25 by the conveying air 24 supplied to the coal pulverizer 30.

  Moreover, the coal 31 supplied to the side burner 1 is temporarily stored in the coal bunker 32, and the coal 31 stored in the coal bunker 32 is supplied to the coal pulverizer 34 by the coal feeder 33 and pulverized to produce pulverized coal. .

  The coal pulverized by the coal pulverizer 34 is conveyed to the side burner 1 by the side burner coal conveyance air 26 by the conveyance air 24 supplied to the coal pulverizer 34.

  In this embodiment, coal is supplied to the burner 2 provided on the front wall 12 and the rear wall 13 and the side burner 1 provided on the side wall 14 of the hopper portion 15 below the furnace 11 through different coal supply systems. However, coal may be supplied to both through the same coal supply system.

  The solid fuel may be pet coke or biomass fuel in addition to the coal described in the present embodiment.

  When the coal supply system of the burner 2 provided on the front wall 12 and the rear wall 13 of the furnace 11 and the side burner 1 provided on the side wall 14 of the hopper portion 15 below the furnace 11 are separately provided, the front wall 12 In addition, the burner 2 on the rear wall 13 and the side burner 1 on the side wall 14 of the hopper 15 can be supplied by changing the type of fuel to be supplied and the particle size distribution during fuel pulverization.

  The fuel 31 that is supplied from the side burner 1 into the furnace 11 and combusted has a long combustion time, so that even coarse particles of fuel can be combusted sufficiently.

  Therefore, the particle size of the fuel 31 supplied from the side burner 1 into the furnace 11 is coarsely pulverized so as to be larger than the particle size of the fuel 27 supplied from the burner 2 installed in the front wall 12 and the rear wall 13 into the furnace 11. By doing so, the pulverization power of the fuel in the coal pulverizer 34 can be reduced.

  In addition, if fuel such as pet coke that has a large amount of fixed carbon and is not easily burned is introduced into the furnace 11 from the side burner 1 and burned, the residence time of the combustion gas in the furnace 11 can be further increased, thereby improving the combustion rate. it can.

  When a plurality of stages of burners 2 are installed on the front wall 12 and the rear wall 13 and the coal supply system is individually arranged for each stage, the lowest installed on the front wall 12 and the rear wall 13 The particle size of the fuel supplied to the burner 2 in the burner stage may be made larger than the particle size of the fuel supplied to the upper burner 2.

  However, there is no problem when the side burner 1 is installed on the side wall 14 of the hopper portion 15 at a position lower than the burner 2 arranged at the lowest position as in the present embodiment. If the particle size of the fuel supplied to the burner 2 installed at the lowermost stage of the front wall 12 and the rear wall 13 is made coarse, the supplied fuel is burned in the furnace 11. There is a possibility of falling to the furnace bottom 16 of the furnace 11.

  Therefore, by installing the side burner 1 on the side wall 14 of the hopper portion 15 of the furnace 11 as in the present embodiment, the rise of the high-temperature combustion gas generated by the combustion of the fuel ejected from the side burner 1 in the furnace 11 Due to the flow, it is possible to suppress the fuel having a coarse particle size supplied from the lowermost burner 2 from falling to the furnace bottom 16 of the furnace 11.

  The high-temperature combustion gas generated by burning the coal of fuel in the furnace 11 is heat-exchanged with a steam generator (not shown) installed in the furnace 11 in the process of flowing down the furnace 11, and the temperature is lowered. Then, it is discharged from the furnace 11 to the outside as combustion exhaust gas 23.

  A heat exchanger 7 and a gas purification device 8 using the combustion exhaust gas 23 as a heating source are sequentially disposed downstream of the furnace 11.

  Combustion air 19 supplied into the furnace 11 from the burner 2 and the after-air port 3 installed on the front wall 12 and the rear wall 13 and the side burner 1 installed on the side wall 14 of the hopper portion 15 is supplied from the forced air blower 9. The generated air 18 is generated by being heated by the heat exchanger 7 using the combustion exhaust gas 23 discharged from the furnace 11 as a heat source.

  The heated combustion air 19 is supplied to the windboxes 4 to 6 installed in the side burner 1, the burner 2, and the after air port 3, respectively, and then the individual side burner 1, burner 2, and It is distributed to the after-air port 3 and supplied into the furnace 11.

  That is, a part of the combustion air 19 heated with the combustion exhaust gas 23 by the heat exchanger 7 is used for the burner branched from the combustion air 19 inside the front wall burner window box 5 and the rear wall burner window box 36. The air is supplied as combustion air 21 and ejected into the furnace 11 from the burners 2 of the front and rear walls 12 and 13 installed inside the front wall burner window box 5 and the rear wall burner window box 36.

  Similarly, a part of the combustion air 19 is supplied to the inside of the front wall after-airport window box 6 and the rear wall after-airport window box 37 as the after-air 22 branched from the combustion air 19. The air is blown into the furnace 11 from the after air ports 3 of the front and rear walls 12 and 13 installed inside the box 6 and the rear wall after air port window box 37.

Similarly, a part of the combustion air 19 is supplied as combustion air 20 for the side burner branched from the combustion air 19 into the right side burner window box 4 and the left side burner window box 35, respectively. The gas is ejected into the furnace 11 from the side burner 1 below the side wall 14 installed inside the burner wind box 4 and the left side burner window box 35.
Next, numerical analysis results when the boiler apparatus of the present embodiment shown in FIG. 1 is applied to a pulverized coal burning boiler apparatus having a generator output of 1000 MW will be described with reference to FIG.

  Here, the numerical analysis program used for the numerical analysis can calculate coal combustion, gas combustion, radiation / convection heat transfer, and flow in three dimensions.

  Verification was performed under conditions that changed the furnaces, fuel flow rates, and coal types of boilers of different sizes, and it was confirmed that NOx, unburnt components, and gas temperature could be calculated with high accuracy.

  Here, as a method of remodeling the boiler apparatus, the burner 2 at the uppermost stage is removed from the burner 2 installed in multiple stages on the front wall 12 and the rear wall 13 of the furnace 11 which is a conventional boiler apparatus, and the same height as the burner 2 at the lowermost stage is removed. The boiler apparatus was designed so that the boiler apparatus can be modified by newly installing the side burner 11 on the side wall 14 below the furnace 11 or the side wall 14 of the hopper 15 located below the burner.

  The characteristic curve values showing the gas temperature, combustion rate, and NOx concentration relative value shown in FIG. 9 are obtained by averaging the physical quantities of the gas temperature, combustion rate, and NOx concentration relative value at the height of the furnace. Yes, the horizontal axis of FIG. 9 is the furnace bottom side on the left end and the ceiling side of the furnace on the right end.

  In FIG. 9, the characteristic curve of the thin line shows the characteristic curve in the case of the conventional boiler device for reference, and the characteristic curve of the thick line shows the characteristic curve in the boiler device of the embodiment of the present invention. .

  As can be understood from the characteristic curve shown in FIG. 9, regarding the gas temperature in the furnace, in the boiler apparatus of this embodiment, the gas temperature at the furnace bottom 16 of the furnace 11 is higher than that in the conventional boiler apparatus. .

  This is because the side burner 1 is disposed on the side wall of the hopper portion 15 located below the lowermost burner 2 installed on the front wall 12 and the rear wall 13 of the furnace 11, so that the gas temperature in the furnace 11 is increased. This is because of the rise.

  Regarding the combustion rate, in the boiler device of this embodiment, the combustion rate at the furnace bottom 16 of the furnace 11 is lower than that of the conventional one. In the conventional boiler device, only the particles after combustion are in the furnace. This is because, in the boiler apparatus of this embodiment, unburned coal is supplied from the side burner 1 installed on the side wall 14 of the furnace 11.

  However, on the downstream side of the burner 2, the combustion rate of the boiler device of the present embodiment is higher than that of the conventional boiler device.

  This is because the residence time of combustion in the furnace 11 is increased by arranging the side burner 1 on the side wall 14 of the furnace 11 in the boiler apparatus of the present embodiment.

  Regarding the NOx concentration, the NOx concentration in the boiler apparatus of this embodiment is higher at the furnace bottom 16 of the furnace 11 than in the conventional boiler apparatus.

  This is because the nitrogen content in the fuel is oxidized by the thermal decomposition reaction and is oxidized.

  However, between the burner 2 and the after-airport 3, the NOx concentration is reduced by the NOx reduction reaction as compared with that of the conventional boiler apparatus.

  Furthermore, in the boiler apparatus of the present embodiment, the NOx concentration was lower also in the downstream of the after air port 3 as compared with the conventional boiler apparatus.

  This is because the temperature is lowered downstream of the after-air port 3 and the regeneration of NOx in the high temperature oxidation region is suppressed.

  In the example of the boiler apparatus of the present embodiment, the NOx concentration was reduced by 17% and the unburned ash content was reduced by 9% compared to the conventional boiler apparatus.

  As is clear from the above description, according to the embodiment of the present invention shown in FIG. 1, the oxidation of nitrogen contained in the combustion gas generated by burning the fuel in the furnace by effectively utilizing the hopper portion of the furnace. It is possible to realize a boiler device with a compact structure that reduces waste and unburned matter.

  Next, the boiler apparatus which is 2nd Example of this invention is demonstrated using FIG.

  In this embodiment, since the basic configuration and operation are the same as those of the boiler apparatus according to the first embodiment shown in FIG. 1, the description of the common configuration and operation is omitted, and different parts are described. Only explained.

  The boiler apparatus of the second embodiment shown in FIG. 4 is reduced from the configuration of the boiler apparatus of the first embodiment shown in FIG. 1 in that the after-air port 3 and the after-air port window box 6 are reduced, and the after-air 22 is supplied into the furnace. This is a configuration example of a single-stage combustion type boiler that burns fuel that is supplied only by the combustion air 21 and 20 supplied from the burner 2 and the side burner 1 without.

  The burner 2 installed in the single-stage combustion type boiler injects and burns a mixture of coal and combustion air into the furnace 11 at a theoretical air ratio or higher (for example, 1.2).

  In the above-described single-stage combustion boiler, unlike the two-stage combustion boiler shown in FIG. 1, a clear incomplete combustion region is not formed, and therefore NOx is generated when the temperature in the furnace becomes high.

  Therefore, in order to reduce the thermal load and NOx concentration on the furnace wall in the vicinity of the burner 2, it is effective to reduce the capacity of the burner 2 or increase the arrangement interval of the burners 2.

  On the other hand, in order to reduce the unburned content in the furnace, it is necessary to ensure a sufficient residence time from the burner 2 to the outlet of the furnace 11, so if the height of the burner installation part is increased, the size of the entire furnace is increased. End up.

  Therefore, as a countermeasure, in the boiler of the single-stage combustion system of the present embodiment, the side burner 1 is the lowermost burner of the burners 2 installed on the front wall 12 and the rear wall 13 of the furnace 11. By installing it on the side wall of the furnace 11 of the rectangular parallelepiped part at the same height or below the burner, or on the side wall of the hopper part 15 below the burner, jetting and burning the fuel In addition to reducing the capacity of the burner 2, not only increasing the height of the furnace 11 or increasing the unburned amount, but also reducing the unburned portion of the boiler, local heat load and NOx.

  Next, the installation position of the side burner 1 provided on the side wall 14 of the hopper portion 15 below the furnace 11 in the boiler apparatus of each embodiment shown in FIGS. 1 and 4 will be described with reference to FIG.

  In FIG. 5, the area 59 of the installation position of the side burner 1 is shown by shading. The distance a between the region 59 where the side burner 1 is installed and the furnace wall of the hopper 15 is determined by the coal properties, slagging properties, and the thermal load on the furnace wall.

Further, the distance b between the lowermost installation height of the burner 2 installed on the front wall 12 and the rear wall 13 of the furnace 11 and the upper limit of the installation height of the side burner 1 is between the front wall 12 and the rear wall 13. It depends on the distance, that is, the depth of the furnace 11, the distance from the burner 2 closest to the side wall 14 in the burner 2, and the capacity of the burner. The distance b is b = 0 and should be larger.
The number and capacity of the side burners 1 to be installed may be determined in consideration of the size of the installation position and the heat load.

  The boiler shown in FIG. 5 is the boiler apparatus of the embodiment shown in FIG. 1 and FIG. 4, and the burners 2 installed on the front wall 12 and the rear wall 13 of the furnace 11 are arranged to face each other. This is a counter-combustion boiler apparatus having a configuration in which the burner 2 is installed in a plurality of stages in the vertical direction of the front wall 12 and the rear wall 13.

  Although the after air port 3 is shown in FIG. 5, the boiler device of the embodiment of FIG. 4 is a single-stage combustion type boiler device that does not include the after air port 3.

  Next, referring to FIG. 2, the side burner 1 provided on the side wall 14 of the hopper portion 15 of the furnace 11 in the boiler apparatus of each embodiment shown in FIGS. An example of arrangement when a plurality of side burners 1 are installed will be described.

  Although the after air port 3 is shown in FIG. 2, the boiler apparatus of the embodiment of FIG. 4 is a single combustion type boiler apparatus that does not include the after air port 3.

  2, FIG. 2 (a) is an example in which a plurality of side burners 1 are arranged, and another arrangement example is shown in FIG. 2 (b) to FIG. 2 (g) for the region surrounded by the broken line.

  FIG. 2A shows an example in which two side burners 1 arranged on each side wall 14 of the furnace 11 are arranged in the horizontal direction.

  The distance c between the two side burners 1 is determined by the fuel properties and the heat load on the furnace wall portion between the burners.

  According to the arrangement example of the side burner 1 shown in FIG. 2A, it is possible to reduce the bias of the heat load in the depth direction of the furnace wall of the furnace 11 and to suppress damage to the furnace wall.

  FIG. 2B shows an example in which two side burners 1 arranged on each side wall 14 of the furnace 11 are arranged in the height direction.

  Since the hopper portion 15 has a structure that becomes narrower toward the lower side, the lower side becomes narrower and it becomes difficult to obtain a sufficient burner interval.

  Therefore, according to the arrangement example of the side burner 1 shown in FIG. 2B, the heat load between the burners is increased by arranging the side burners 1 in the height direction, but the side burner is further down rather than arranged horizontally. Since 1 can be arranged, it is suitable when importance is attached to the reduction of NOx and unburned content in the combustion gas.

  FIG. 2C shows a hybrid type in which two side burners 1 arranged on each side wall 14 of the furnace 11 are arranged obliquely by combining the arrangements shown in FIGS. 2A and 2B.

  When the water pipe passes diagonally through the side wall 14, the side burner 1 is arranged obliquely in accordance with the water pipe arrangement angle, thereby reducing the change in the water pipe arrangement direction due to the installation of the side burner 1. it can.

  FIG. 2D to FIG. 2G show an example in which three side burners 1 arranged on each side wall 14 of the furnace 11 are arranged.

  Among these, FIG.2 (d) is an example which arranged the three side burners 1 in the horizontal direction, and is suitable when reducing the bias | inclination of a thermal load.

  FIG. 2 (e) shows an example in which a total of three side burners 1 arranged on each side wall 14 of the furnace 11 are arranged in two stages, one in the lower stage and two in the upper stage.

  The installation position of the side burner 1 can be arranged low while taking the installation intervals c and c ′ of the side burners 1 large.

  In addition to the above, even if the three side burners 1 are arranged in the height direction as shown in FIG. 2 (f), the three side burners 1 are arranged in two stages as shown in FIG. 2 (g). One and two may be arranged in the lower stage.

  The case where four or more side burners 1 provided on the side wall 14 of the furnace 11 in the boiler apparatus of the above-described embodiment are arranged is the same as the case shown in each drawing of FIG. In order to increase the combustion time, it is preferable to increase the number of stages and arrange them in the height direction.

  Next, with reference to FIG. 3, in the case where two side burners 1 provided on the side wall 14 at the bottom of the furnace 11 in the boiler apparatus of the present embodiment shown in FIGS. 1 and 4 are installed vertically along the height direction. An example of improving the combustibility by adjusting the fuel ejection direction 58 for ejecting fuel from the side burner 1 into the furnace 11 upward or downward with respect to the horizontal direction will be described.

  Although the after air port 3 is shown in FIG. 3, the boiler apparatus of the embodiment of FIG. 4 is a single combustion type boiler apparatus that does not include the after air port 3.

  As shown in FIG. 3 (b), which is an AA cross section of FIG. 3 (a) and FIG. As shown, two side burners 1 are installed vertically along the height direction.

  The side burner 1 installed on the side wall 14 is not heated from the lower side of the furnace 11, and the combustion state tends to become unstable when fuel with poor combustibility is burned, and there is a possibility of misfire.

  Therefore, when the side burner 1 is disposed so that the jets of fuel ejected from the plurality of side burners 1 installed vertically along the height direction collide with each other in the vicinity of the side wall 14, the fuel and the combustion air Mixing is promoted to improve ignition and flame holding properties.

  Moreover, the coal 27 supplied to the burner 2 of the front wall 12 and the rear wall 13 and the coal 31 supplied to the side burner 1 of the side wall 14 are temporarily stored in the coal bunkers 28 and 32 as described above, and the coal feeder 29, After supplying the coal pulverizers 30 and 34 to the coal pulverizers 30 and 34 to produce pulverized coal, the conveying air 24 is supplied to the coal pulverizers 30 and 34 so that the coal pulverizers 30 and 34 can convey the coal for the burner. The pulverized coal is conveyed to the burner 2 and the side burner 1 by the gas 25 and the coal conveying gas 26 for the side burner, respectively.

  Next, referring to FIGS. 6 to 8, a coal supply system for supplying coal of fuel to the burner 2 and the side burner 1 installed in the furnace 11 in the boiler apparatus of the present embodiment shown in FIGS. 1 and 4, and combustion The example of each system diagram of the air supply system which supplies combustion air to the burner 2, the side burner 1, and the after-air port 3 which installed the working air in the furnace 11 is shown.

  6 to 8, the after-air port 3 is shown. However, with respect to the boiler apparatus of the embodiment of FIG. 4, a coal supply system that supplies fuel coal to the burner 2 and the side burner 1, and combustion air are used. Although each system of the air supply system supplied to the burner 2 and the side burner 1 installed in the furnace 11 is common, the after-air port 3 and the air supply system for supplying combustion air to the after-air port 3 are not provided It becomes.

  In FIG. 6, in the boiler apparatus of this embodiment, there are four coal supply systems, one for each of the left and right side burners 1 installed on the side wall 14 at the bottom of the furnace 11, the burner 2 installed on the front wall 12 and the rear wall 13. is there.

  In addition, the combustion air 19 is heated by the heat exchanger 7 from the air 18 supplied from the forced air blower 9.

  A part of the combustion air 19 supplied through the flow path for supplying the combustion air 19 heated from the heat exchanger 7 is put inside the front wall burner wind box 5 and the rear wall burner wind box 36 for the combustion. Furnace from the burners 2 of the front wall 12 and the rear wall 13 respectively supplied through the branch flow paths as the burner combustion air 21 branched from the air 19 and installed in the front wall burner wind box 5 and the rear wall burner window box 36. 11 spouts out.

  Similarly, a part of the combustion air 19 is respectively supplied to the inside of the front wall after-airport window box 6 and the rear wall after-airport window box 37 as after-air 22 branched from the combustion air 19 through the branch flow path. The air is blown into the furnace 11 from the after-air port 3 of the front wall 12 and the rear wall 13 installed inside the wall-after-airport window box 6 and the rear-wall after-airport window box 37.

  Similarly, a part of the combustion air 19 is supplied to the insides of the right side burner wind box 4 and the left side burner window box 35 as side burner combustion air 20 branched from the combustion air 19 through branch channels. The gas is ejected into the furnace 11 from the side burner 1 below the side wall 14 installed inside the right side burner window box 4 and the left side burner window box 35.

  Further, dampers 42 and 45 for adjusting the flow rate of the side burner combustion air 20 are installed in the branch flow channel before the right side burner window box 4 and the left side burner window box 35.

  The dampers 43 and 46 for adjusting the flow rate of the burner combustion air 21 are installed in the branch flow channel before the front wall burner window box 5 and the rear wall burner window box 36.

  Similarly, dampers 44 and 47 for adjusting the flow rate of the after-air 22 are installed in the branch flow channel before the front wall after-airport window box 6 and the rear wall after-airport window box 37.

  Further, the flow rates of the side burner combustion air 20, the burner combustion air 21, and the after air 22 are calculated, and the openings of the dampers 42 to 47 are controlled so that these air amounts coincide with the calculated flow rates. A control device 41 is installed.

  The opening of the dampers 42 to 47 is controlled based on the opening command signal calculated and output by the control device 41, and the burner combustion air 21, the after air 22, and the side supplied to the furnace 11 The flow rate of the combustion air of the burner combustion air 20 is adjusted.

  In the air supply system for supplying combustion air in the boiler apparatus of the present embodiment shown in FIG. 7, the damper 44 installed in the branch flow channel before the front wall after-airport window box 6 and the rear wall after-airport window box 37, 47 and the opening degree of the dampers 43 and 46 installed in the branch flow path in front of the front wall burner wind box 5 and the rear wall burner wind box 36 are respectively adjusted and supplied from the burner 2 into the furnace 11. The flow rate of the burner combustion air 21 and the flow rate of the after air 22 supplied into the furnace 11 from the after air port 3 are respectively controlled.

  For the side burner supplied from the side burner 1 into the furnace 11 by adjusting the opening degree of the dampers 44 and 47 installed in the branch flow path before the right side burner window box 4 and the left side burner window box 35. The flow rate of the combustion air 20 is controlled.

  As described above, the flow rate of the burner combustion air 21 and the flow rate of the side burner combustion air 20 are adjusted based on the flow rate command from the control device 41 and the opening degree of the dampers 43 and 46 and the opening degree of the dampers 42 and 45, respectively. It is controlled by doing.

  As shown in FIG. 7, the dampers 42 and 45 are not the branch flow paths in front of the right side burner window box 4 and the left side burner window box 35, but the front wall burner window box 5 and the rear wall burner window box 36. You may install in the branched flow path which becomes further upstream of the said dampers 43 and 46 before this.

  Further, in the air supply system for supplying combustion air in the boiler apparatus of the present embodiment shown in FIG. 8, a part of the combustion air 19 that has flowed down the flow path that leads the combustion air 19 heated from the heat exchanger 7. However, the right side burner window box 4 and the right wall burner window box 4 are configured independently of the front wall burner window box 5 and the rear wall burner window box 36. The left side burner window box 35 is supplied through branching channels that branch into a total of six branching systems.

  Therefore, by adjusting the opening degree of the dampers 42 and 45 installed in the independent branch flow paths before the right side burner window box 4 and the left side burner window box 35 based on the flow command from the control device 41, the side The flow rate of the combustion air 20 for the side burner supplied from the burner 1 into the furnace 11 is controlled.

  In addition, in the boiler apparatus of each Example shown in FIGS. 6-8, although the example of the boiler apparatus provided with the wind box type combustion air supply system was shown, it was equipped with the scroll burner type combustion air supply system. The same applies to the boiler device.

  As is apparent from the above description, according to the embodiment of the present invention shown in FIG. 4, the oxidation of nitrogen contained in the combustion gas generated by burning the fuel in the furnace by effectively utilizing the hopper portion of the furnace. It is possible to realize a boiler device with a compact structure that reduces waste and unburned matter.

  The boiler apparatus which is 3rd Example of this invention is demonstrated using FIG.

  In this embodiment, since the basic configuration and operation are the same as those of the boiler apparatus according to the first embodiment shown in FIG. 1, the description of the common configuration and operation is omitted, and different parts are described. Only explained.

  In the boiler apparatus of the third embodiment shown in FIG. 10, an apparatus for preventing ash adhesion in the vicinity of the side burner 1 installed on the side wall 14 of the furnace 11 in addition to the boiler apparatus of the embodiment shown in FIGS. 1 and 4. The example provided with is shown.

  In order to simplify the description, the side burner 1 is shown only on the front side in the boiler apparatus of the present embodiment, but it is also installed on the back side of the figure.

  Further, not only one side burner 1 but also a plurality of side burners 1 may be installed per wall surface 14.

  As shown in FIG. 10, the hopper 15 at the lower part of the furnace 11 in which the side burner 1 is installed has a structure that gradually becomes narrower toward the bottom of the furnace bottom 16.

  Therefore, depending on the operation conditions and the attachment position of the side burner 1, the heat load per unit volume may be higher in the vicinity of the side burner 1 than in the portion where the burner 2 is installed on the front wall 12 and the rear wall 13 of the furnace 11. There is sex.

  Further, since the distance between the flame formed by combustion of the fuel ejected from the side burner 1 and the wall surface of the hopper 15 is close, the thermal load on the inner surface of the hopper 15 tends to be high.

  When the thermal load on the inner surface of the hopper 15 increases, a phenomenon occurs in which the ash attached to the inner surface of the hopper softens or melts.

  Such a phenomenon in which molten or softened ash adheres to the wall surface is referred to as a slagging phenomenon. However, when the slagging phenomenon occurs, heat transfer to the water wall of the boiler furnace 11 is hindered, resulting in a problem that the thermal efficiency is lowered.

  Further, the hopper portion 15 is a place for receiving ash falling from the ceiling wall 17 above the furnace 11, and is the place having the largest ash load in the furnace 11.

  For this reason, if the slagging phenomenon described above occurs, the hopper 15 may melt the ash and form a lump.

  It is important to discharge the ash because the ash that has become a lump will cause the boiler to stop operating unless it is discharged outside the furnace 11.

  Therefore, in the boiler apparatus of this embodiment, first, any one of water, exhaust gas, or air is put into the furnace 11 at the lower part of the side wall 14 of the furnace 11 around the side burner 1 installed on the side wall 14. A soot blow 48 to be ejected is installed.

  The soot blow 48 is a device that removes ash adhering to the wall surface of the hopper portion 15 by ejecting a high-pressure fluid into the furnace 11 at a high speed from a pipe (not shown) having a mechanism for insertion into the furnace 11.

  By ejecting the fluid into the furnace using the soot blow 48, even if slagging phenomenon occurs and ash adheres to the hopper portion 15, it can be removed.

  Further, since the thermal load around the side burner 1 becomes high, it is desirable that a plurality of soot blows 48 be arranged around the side burner 1 below the side wall 14 of the furnace 11.

  In the present embodiment, the case where four soot blowers 48 are installed around the side burner 1 is shown, but this is not a limitation.

  Of the fluid ejected from the soot blow 48, water has the highest ash removal capability.

  Water has a larger momentum than gas, and its temperature is low, so it is easy to give a thermal shock to the ash.

  Moreover, when exhaust gas is used as the fluid to be ejected, there is an advantage that ash can be removed without increasing the air ratio in the reduction zone. If the air ratio in the reduction zone is not increased, the combustion in the furnace is not affected even if the soot blow 48 is started.

  Furthermore, in the boiler apparatus of the present embodiment, a large number of holes 49 are provided in the wall surfaces of the front wall 12 and the rear wall 13 of the hopper portion 15, and either exhaust gas or air fluid is supplied into the furnace 11 from the holes 49. It is configured to erupt.

  The wall surfaces of the front wall 12 and the rear wall 13 of the hopper portion 15 are arranged obliquely, and in an environment where a slagging phenomenon occurs, ash has a large adhesive force and may stay on the wall surface without slipping off. .

  Therefore, in the boiler apparatus of the present embodiment, fluid is ejected from a large number of holes 49 provided in the wall surfaces of the front wall 12 and the rear wall 13 of the hopper portion 15, so that the ash staying on the wall surface rises and the ash is peeled off from the wall surface It becomes easy to do.

  Moreover, since the vicinity of the wall surface of the front wall 12 and the rear wall 13 of the hopper part 15 is cooled by the fluid ejected into the furnace from the holes 49 provided in large numbers, an effect of making it difficult for ash to adhere is expected.

  Here, if exhaust gas is used as the fluid, the air ratio in the reduction zone is not increased as described above, and the combustion in the furnace is not affected.

  The soot blow 48 and the hole 49 for preventing ash adhesion shown in this embodiment may be installed in combination, or only one of them may be installed.

  According to the present embodiment, a boiler device having a compact structure that reduces nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace. And the modification method of a boiler apparatus is realizable.

  The boiler apparatus which is 4th Example of this invention is demonstrated using FIG.

  In this embodiment, since the basic configuration and operation are the same as those of the boiler apparatus according to the first embodiment shown in FIG. 1, the description of the common configuration and operation is omitted, and different parts are described. Only explained.

  In the boiler apparatus of the fourth embodiment shown in FIG. 11, fuel is supplied from the side burner 1 to the side burner 1 installed on the side wall 14 of the furnace 11 in the boiler apparatus of the embodiment shown in FIGS. 1 and 4. The example provided with the mechanism which controls the ejection direction 58 ejected in 11 is shown.

  The side burner 1 may have not only one but also a plurality of side burners per wall of the side wall 14, and the installation direction of the side burner 1 can be deflected in the vertical direction so that the ejection direction 58 for ejecting fuel can be controlled. ing.

  First, when the ejection direction 58 of the fuel ejected from the side burner 1 is directed downward from the horizontal direction, the traveling direction of the combustion gas generated by the combustion of the injected fuel once goes downward of the furnace. Thereafter, the combustion gas that has traveled downward near the center of the furnace 11 turns in the direction above the furnace.

  In this way, when the side burner 1 is disposed downward, the combustion gas injected and burned from the side burner 1 has a longer residence time in the furnace than in the case where the combustion gas is injected parallel to the horizontal direction. Can be long.

  If the residence time of the combustion gas in the furnace becomes longer, the unburned amount in the ash can be reduced at the outlet of the boiler device, the reduction of NOx in the reduction zone proceeds, and the NOx concentration in the combustion gas at the boiler outlet is reduced. Can be made.

  As described above, only by adjusting the arrangement direction of the side burner 1, without changing the installation position of the side burner 1 installed at the lower part of the side wall 14 of the furnace 11, the unburned ash content and NOx in the combustion gas are reduced. Since the generation amount can be reduced, it is an effective means when there is a restriction on the installation of the side burner 1.

  On the other hand, when the ejection direction 58 of the fuel ejected from the side burner 1 is directed upward from the horizontal direction, the traveling direction of the generated combustion gas is directed upward, so that the thermal load on the hopper portion 15 below the furnace 11 is small. Become.

  This is an effective means when the slagging phenomenon is likely to occur in the hopper 15 depending on the type of coal and the operating conditions.

  In particular, when burning coal with properties that are prone to slagging, or when burning fuel with poor pulverization properties and a large amount of coarse particles, the side burner 1 can be installed with the orientation of the side burner upward and fixed. It is possible to omit a mechanism for adjusting the ejection direction 58 of the fuel ejected from the burner 1.

  Further, if the ejection direction 58 of the fuel ejected from the side burner 1 can be controlled up and down, a combustion state that is more suitable for the operating state can be selected, so that the operational effect is increased.

  According to the present embodiment, a boiler device having a compact structure that reduces nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace. And the modification method of a boiler apparatus is realizable.

  The boiler apparatus which is 5th Example of this invention is demonstrated using FIG.

  In this embodiment, since the basic configuration and operation are the same as those of the boiler apparatus according to the first embodiment shown in FIG. 1, the description of the common configuration and operation is omitted, and different parts are described. Only explained.

  In the boiler apparatus of the fifth embodiment shown in FIG. 12, the side burner combustion air 20 is supplied to the side burner 1 installed on the side wall 14 of the furnace 11 to the boiler apparatus of the embodiment shown in FIGS. An example in which a connecting duct 53 is provided is shown.

  The combustion air 19 heated by heat exchange in the heat exchanger 7 is guided by the combustion air duct 50 and supplied to the vicinity of the furnace 11.

  Air is supplied from the combustion air duct 50 to the wind box 36 of the burner 2 and the wind box 37 of the after-air port 3 of the rear wall 13 through the rear branch duct 51.

  If the damper for adjusting the amount of air supplied to the post-can branching duct 51 is installed inside the post-can branching duct 51, the structure becomes simple.

  Similarly, air is supplied from the combustion air duct 50 to the burner 2 wind box 5 on the front wall 12 and the wind box 6 on the after-air port 3 through the can front branch duct 52.

  In FIG. 12, only the case where the combustion air duct 50, the post-can branching duct 51, and the pre-can branching duct 52 are installed only on one side wall of the furnace 11 is shown, but these are set on the left and right side walls 14, respectively. You may do it.

  Since the side burner 1 is installed on the side wall 14 below the furnace 11, it may be difficult to hold the flame.

  In such a case, it is necessary to stably supply the side burner combustion air 20 to the side burner 1, but it is effective to supply air from a place where the pressure is high for stable supply.

  Therefore, in the boiler apparatus of the present embodiment, the air is configured to branch the connection duct 53 from the middle of the pre-can branch duct 52 and supply the air to the wind box 4 of the side burner 1 as the side burner combustion air 20. .

  Since this branching location is located upstream of the damper 54 installed in the connection duct 53, the pressure is high and suitable as a location where air is branched to the side burner 1 as the side burner combustion air 20.

  Further, if a damper 54 for adjusting the air amount of the side burner combustion air 20 supplied to the side burner 1 is installed in the connection duct 53, the structure becomes simple.

  If the connection duct 53 is arranged vertically as shown in FIG. 12, ash is not deposited in the connection duct 53, and maintenance is facilitated.

  Since the furnace 11 expands due to heat, it is necessary to configure the connection duct 53 so that the position of the connection duct 53 can move in the vertical direction. In such a case, a mechanism (expansion) that expands and contracts in the middle of the connection duct 53. It is good to install.

  When a single-stage combustion boiler apparatus without an after-air port is remodeled into a two-stage combustion system with an after-air port, the position of the burner 2 installed on the front wall 12 and the rear wall 13 of the furnace 11 is changed. In many cases, the performance of a boiler is improved by changing or adding an after-air port 3.

  Therefore, first, the burner 2 installed at the highest level among the burners 2 installed over a plurality of stages on the front wall 12 and the rear wall 13 of the furnace 11 is removed.

  Next, if the side burner 1 is installed on the side wall 14 at the bottom of the furnace 11 or the side wall 14 of the hopper portion 15, the connection duct so as to take in the side burner combustion air 20 supplied to the side burner 1 from the duct near the side wall 14. By arranging 53, the boiler device can be remodeled at a low cost with few remodeling points.

  According to the present embodiment, a boiler device having a compact structure that reduces nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace. And the modification method of a boiler apparatus is realizable.

  The boiler apparatus which is 6th Example of this invention is demonstrated using FIG.

  In this embodiment, since the basic configuration and operation are the same as those of the boiler apparatus according to the first embodiment shown in FIG. 1, the description of the common configuration and operation is omitted, and different parts are described. Only explained.

  In the boiler apparatus of the sixth embodiment shown in FIG. 13, particles are added to the upstream side of the side burners 56 and 57 installed in the lower part of the side wall 14 of the furnace 11 in the boiler apparatus of the embodiment shown in FIGS. 1 and 4. The example provided with the separation apparatus 53 is shown.

  In the present embodiment, a case will be described in which a device for separating particles according to the particle size of solid fuel is installed as the particle separation device 55.

  The solid fuel particles supplied from the coal pulverizer 33 to the side burners 56 and 57 have a particle size distribution.

  Depending on the density of the solid fuel particles and the structure of the side burners 56 and 57, when the solid fuel particles are coarse particles of 100 μm or more, the solid fuel injected from the side burners 56 and 57 into the furnace 11 is used. Tends to fall to the furnace bottom 16 of the furnace 11.

  Accordingly, the solid fuel particles are separated by the particle separation device 55, fine solid fuel is supplied to the side burner 56 arranged on the lower side, and coarse solid fuel is supplied to the side burner 57 arranged on the upper side.

  As a result, the combustion gas generated by the combustion of the fine particle fuel ejected from the lower side burner 56 proceeds in an upward flow in the furnace 11, so that the coarse particles supplied from the upper side burner 57 Since the solid fuel rises by this upward flow of combustion gas, it can be prevented from falling to the furnace bottom 16.

  Further, the flame generated by the combustion of the fuel injected from the lower side burner 56 is cooled by the hopper 15 and easily misfires. However, in this embodiment, the solid fuel injected from the lower side burner 56 is Since fine solid fuel is used, the combustion state is maintained and the situation of misfire is prevented.

  Next, a description will be given of a case where a device for separating solid fuel and ash as a particle separation device 55 is installed. If a solid fuel contains a non-burning substance such as ash, flame holding performance may deteriorate. is there.

  In such a case, since the substance can be separated by specific gravity, coefficient of restitution, particle size, etc. by the particle separation device 55, for example, when solid fuel and ash are contained in the fuel, Can be separated.

  As a result, since the ratio of ash in the fuel injected into the furnace 11 from the side burners 56 and 57 is reduced, the flame holding property is improved.

  In addition, although the after-air port 3 is described in the boiler apparatus of each Example shown in FIGS. 10-13 mentioned above, the boiler apparatus corresponding to the Example of FIG. 4 is not equipped with this after-air port 3. It becomes a combustion-type boiler device.

  According to the present embodiment, a boiler device having a compact structure that reduces nitrogen oxides and unburned components contained in combustion gas generated by burning fuel in the furnace by effectively using the hopper portion of the furnace. And the modification method of a boiler apparatus is realizable.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a boiler device that reduces NOx concentration and unburned content in combustion gas and a method for remodeling the boiler device.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram which shows the boiler apparatus which is 1st Example of this invention. The figure which shows the example of arrangement | positioning of the side burner installed in the boiler apparatus which is the Example of FIG. The figure which shows the example of arrangement | positioning of the side burner installed in the boiler apparatus which is the Example of FIG. The schematic block diagram which shows the boiler apparatus which is 2nd Example of this invention. The figure which shows the installation position of the side burner installed in the boiler apparatus which is each Example of FIG.1 and FIG.4. The system diagram which shows the supply system of the combustion air and fuel in the boiler apparatus which is each Example of FIG.1 and FIG.4. FIG. 5 is another system diagram showing a combustion air and fuel supply system in the boiler apparatus according to each embodiment of FIGS. 1 and 4. FIG. 5 is still another system diagram illustrating a combustion air and fuel supply system in the boiler apparatus according to each embodiment of FIGS. 1 and 4. The characteristic view which shows the numerical analysis result for the pulverized coal burning boiler which is the Example of FIG. The schematic block diagram which shows the boiler apparatus which is 3rd Example of this invention. The schematic block diagram which shows the boiler apparatus which is 4th Example of this invention. The schematic block diagram which shows the boiler apparatus which is 5th Example of this invention. The schematic block diagram which shows the boiler apparatus which is 6th Example of this invention.

Explanation of symbols

  1: side burner, 2: burner, 3: after-air port, 4: side burner window box, 5: burner window box, 6: after-air port window box, 7: heat exchanger, 8: gas purifier, 9: forced air Machine: 10: boiler, 11: furnace, 12: front wall, 13: rear wall, 14: side wall, 15: hopper, 16: furnace bottom, 17: ceiling wall, 18: air, 19: combustion air, 20: Side burner combustion air, 21: Burner combustion air, 22: After air, 23: Combustion gas, 24: Carrier air, 25: Burner coal transport air, 26: Side burner carrier air, 27: Coal, 28: Coal Bunker, 29: Coal feeder, 30: Coal pulverizer, 31: Coal, 32: Coal bunker, 33: Coal pulverizer, 34: Coal pulverizer, 35: Left side burner window box, 36: Rear wall -Winner window box, 37: rear wall after air wind box, 38: left side burner conveying air, 39: rear wall burner combustion air, 40: rear wall after air combustion air, 41: control device, 42: air conditioning damper 43: Air conditioning damper, 44: Air conditioning damper, 45: Air conditioning damper, 46: Air conditioning damper, 47: Air conditioning damper, 48: Soot blow, 49: Ash adhesion, corrosion prevention port, 50: For combustion air Duct: 51: branch duct after the can, 52: branch duct before the can, 53: connection duct, 54: damper, 55: particle separator, 56: lower side burner, 57: upper side burner, 58: jet direction of the burner, 59: Side burner installation area.

Claims (17)

  A furnace comprising a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper provided at a lower portion of the rectangular parallelepiped portion, and a furnace A plurality of burners installed on the front wall and the rear wall of the furnace for supplying fuel and combustion air into the furnace and burning, respectively, and installed on the front wall and the rear wall of the furnace that is the upper part of the burner A boiler apparatus having a plurality of after-air ports for supplying air into a furnace, the same height as the burner disposed at the lowermost position among the burners installed on the front wall and the rear wall of the furnace, or the burner A boiler apparatus comprising: a side burner for injecting and burning fuel on a side wall of the furnace of the rectangular parallelepiped portion located at a lower position or a side wall of a hopper portion located at a position lower than the burner.   A furnace comprising a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper provided at a lower portion of the rectangular parallelepiped portion, and a furnace A boiler apparatus provided with a plurality of burners installed on the front wall and the rear wall of the furnace and supplying fuel and combustion air into the furnace for combustion, wherein the burner is installed on the front wall and the rear wall of the furnace The fuel is placed on the side wall of the furnace below the rectangular parallelepiped portion which is the same height as the burner disposed at the lowest position or at a position below the burner, or the side wall of the hopper portion which is located below the burner. A boiler apparatus comprising a side burner for jetting and burning.   3. The boiler apparatus according to claim 1, wherein a plurality of the side burners are respectively installed on side walls on both sides of the furnace below the rectangular parallelepiped part or on both side walls of the hopper part. 4. .   The boiler apparatus according to claim 1 or 2, wherein the plurality of burners installed on the front wall and the rear wall of the furnace are opposed to the burner installed on the front wall and the burner installed on the rear wall. A boiler apparatus characterized by being arranged to constitute a counter-combustion boiler apparatus.   5. The boiler apparatus according to claim 4, wherein a plurality of the side burners are respectively installed on a side wall of a furnace below the rectangular parallelepiped part or a side wall of a hopper part. 6.   The boiler apparatus according to claim 3 or 5, wherein a plurality of the side burners installed are arranged along a horizontal direction on a side wall of a furnace below the rectangular parallelepiped part or a side wall of a hopper part. apparatus.   The boiler apparatus according to claim 3 or 5, wherein a plurality of the side burners installed are arranged along a vertical direction on a side wall of a furnace below the rectangular parallelepiped part or a side wall of a hopper part. Boiler equipment.   3. The boiler apparatus according to claim 1, wherein the side wall of the hopper portion is located below a burner disposed at a lowermost position among the burners installed on a front wall and a rear wall of the furnace. A boiler device characterized in that a soot blower for injecting water, combustion exhaust gas, or air into the furnace is installed in the lower part of the furnace.   The boiler apparatus according to claim 1 or 2, wherein a plurality of holes for ejecting fluid to the inside and peeling off ash are provided in a front wall and a rear wall forming the hopper. Boiler equipment.   3. The boiler apparatus according to claim 1, wherein the side burner is set so that an ejection direction in which fuel is ejected into a furnace is upward from a horizontal direction. 4.   3. The boiler apparatus according to claim 1, wherein the side burner includes a mechanism for controlling a jet direction of fuel jetted from the side burner into the furnace. 4.   The boiler apparatus according to claim 3 or 5, wherein the side burner is arranged such that a flame formed in a furnace collides with each other in a direction in which fuel is ejected from the side burner. Boiler equipment.   3. The boiler apparatus according to claim 1, wherein the particle size of the solid fuel that is the fuel ejected from the side burner installed on the side wall of the lower part of the furnace or the side wall of the hopper is determined by the front wall and the rear wall of the furnace. A boiler apparatus characterized by using a solid fuel having a particle diameter coarser than the particle diameter of the solid fuel, which is a fuel ejected from a burner installed in the boiler.   The boiler apparatus according to claim 1 or 2, wherein the fuel ejected from the side burner installed on the side wall of the furnace below the rectangular parallelepiped part or the side wall of the hopper part is installed on the front wall and the rear wall of the furnace. A boiler device using a different type of fuel from the fuel ejected from the burner.   The boiler apparatus according to claim 3 or 5, wherein a plurality of side burners installed on the side wall of the furnace below the rectangular parallelepiped part or the side wall of the hopper part are respectively arranged in the vertical direction. The solid fuel, which is the fuel ejected from the side, is ejected from the side burner arranged at the lower part, and the solid fuel of coarse particle diameter is ejected from the side burner arranged at the upper part into the furnace or hopper part, respectively. A boiler device characterized by that.   A furnace comprising a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper provided at a lower portion of the rectangular parallelepiped portion, and a furnace A plurality of burners are installed on the front wall and the rear wall, respectively, and a plurality of burners for supplying and burning fuel and combustion air into the furnace and burning are installed on the front wall and the rear wall of the furnace that is the upper part of the burner. In a method for remodeling a boiler apparatus having a plurality of after-air ports for supplying combustion air into the furnace, the uppermost burner is removed from the existing burners installed on the front wall or the rear wall of the furnace. The rectangular parallelepiped furnace side wall or the burner at the same height as the burner disposed at the lowest position among the burners installed on the front wall and the rear wall of the furnace, or at a position below the burner, or the burner Is a lower position than Method for retrofitting a boiler apparatus characterized by by jetting fuel into the side wall parts are modified to install a side burner to burn.   A furnace comprising a rectangular parallelepiped portion composed of a front wall, a rear wall, and a side wall disposed between the front wall and the rear wall, and a hopper provided at a lower portion of the rectangular parallelepiped portion, and a furnace In a method for remodeling a boiler apparatus, which is provided with three or more stages on each of the front wall and the rear wall of the boiler, and is provided with a plurality of burners for supplying and burning fuel and combustion air into the furnace, the front wall or the rear wall of the furnace The uppermost burner is removed from the existing burners installed at the same level as the burner arranged at the lowest position among the burners installed on the front wall and the rear wall of the furnace or from the burner. Further, a modification is made so that a side burner for injecting and burning fuel is installed on the side wall of the furnace of the rectangular parallelepiped portion which is located below or the side wall of the hopper portion located below the burner. Remodeling boiler equipment.

Images